Pathophysiology Of Heart Disease Pdf Download
More than 1 million cases of shock are estimated to present to U.S. hospital EDs each year. The presentation may be cryptic, as in the patient with compensated heart failure, or obvious as in the ultimate shock state of cardiac arrest. Despite aggressive treatment, mortality from shock remains high. Approximately 30 to 45 percent of patients in septic shock, and 60 to 90 percent for those with cardiogenic shock, die within 1 month of presentation. The definition and treatment of shock continues to evolve. With a contemporary understanding of the disease and new evolving technology, the emergency physician can recognize shock at an earlier stage and initiate expert, timely intervention. The general approach to a patient in the initial stages of shock follows similar principles regardless of the inciting factors or etiology. Keywords: Shock, peripheral circulatory failure, cardiogenic shock ,anaphylactic shock.
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Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
Definition
Shock is defined as circulatory
insufficiency that creates an imbalance between
tissue oxygen supply and oxygen demand. The
result of shock is global tissue hypoperfusion and
is associated with a decreased venous oxygen
content and metabolic acidosis (lactic acidosis).(4)
Pathophysiology(4)
Shock is classified into four categories by
etiology:
(1) Hypovolemic (caused by inadequate
circulating volume),
(2) Cardiogenic (caused by inadequate
cardiac pump function),
Pathophysiology and management of
different types of shock
Monira Taha1 , Adel Elbaih 2 .
1, 2Assistant professor of Emergency Medicine, Faculty of Medicine, Suez Canal University, Egypt.
Corresponding author : Adel Elbaih, Email ID : elbaihzico@yahoo.com
ABSTRACT
More than 1 million cases of shock are estimated to present to U.S. hospital EDs each
year. (1) The presentation may be cryptic, as in the patient with compensated heart failure, or
obvious as in the ultimate shock state of cardiac arrest. Despite aggressive treatment, mortality
from shock remains high. Approximately 30 to 45 percent of patients in septic shock, and 60
to 90 percent for those with cardiogenic shock, die within 1 month of presentation. (2,3) The
definition and treatment of shock continues to evolve. With a contemporary understanding of
the disease and new evolving technology, the emergency physician can recognize shock at an
earlier stage and initiate expert, timely intervention. The general approach to a patient in the
initial stages of shock follows similar principles regardless of the inciting factors or etiology.
Keywords: Shock, peripheral circulatory failure, cardiogenic shock ,anaphylactic shock.
(3) Distributive (caused by peripheral
vasodilatation and mal distribution of
blood flow),
(4) Obstructive (caused by extra cardiac
obstruction to blood flow).
Clinically, shock may have a predominant
cause, but as the shock state persists or progresses
to irreversible end organ damage, other
pathophysiologic mechanisms become operative.
Knowledge of the principles of oxygen delivery
and consumptionis are important to the
understanding of shock. A maximum of four
molecules of oxygen is loaded onto each molecule
of hemoglobin as it passes through the lungs. If
all available oxygen sites are occupied(four per
molecule of hemoglobin), arterial oxygen
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Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
saturation (Sao2)is 100 percent . Arterial oxygen
content (Cao2) is the amount of oxygen bound to
hemoglobin plus the amount dissolved in plasma.
Oxygen is delivered to the tissues by the pumping
function (cardiac output) of the heart. Systemic
oxygen delivery (Do2) is the product of the Cao2
and cardiac output (CO). Systemic oxygen
consumption (Vo2) comprises a sensitive balance
between supply and demand.
Normally, the tissues consume
approximately 25 percent of the oxygen carried
on hemoglobin, and venous blood returning to
the right heart is approximately 75percent
saturated [mixed venous oxygen saturation
(pulmonary artery)(Smvo2)].
When oxygen supply is insufficient to
meet demand, the first compensatory mechanism
is an increase in CO. If the increase in CO is
inadequate, the amount of oxygen extracted from
hemoglobin by the tissues increases, which
decreases Smvo2.When compensatory
mechanisms fail to correct the imbalance between
tissue supply and demand, anaerobic metabolism
occurs, resulting in the formation of lactic acid.
Lactic acid is rapidly buffered, resulting in the
formation of measured lactate; normally between
0.5 and1.5 mM/L. An elevated lactate level is
associated with an Smvo2 <50percent. Most cases
of lactic acidosis are a result of inadequate oxygen
delivery, but lactic acidosis occasionally can
develop from an excessively high oxygen
demand, for example, in status epilepticus.
Figure (1) with insufficient oxygen supply,
pyruvate will be diverted to lactate, there by
assuring regeneration of NAD+ from NADH.
This will enable glycolysis, and the
accompanying ATP production to proceed.(5)
In other cases, lactic acidosis occurs
because of an impairment in tissue oxygen
utilization, as in septic shock and post
resuscitation from cardiac arrest; a normal Smvo2
with an elevated lactate indicates such an
impairment. Elevated lactate is a marker of
impaired oxygen delivery and/or utilization and
correlates with short-term prognosis of critically
ill patients in the ED.Smvo2 can also be used as
a measure of the balance between tissue oxygen
supply and demand. Smvo2 is obtained from the
pulmonary artery catheter, but similar information
can be obtained by central venous blood
cannulation (Scvo2). Scvo2 correlates well with
Smvo2and can be more easily obtained in the ED
setting.(6)
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Shock is usually, but not always, associated with
systemic arterial hypotension; i.e., systolic blood
pressure less than 90 mm Hg. Pressure is the
product of flow and resistance [mean arterial
pressure(MAP) = CO X systemic vascular
resistance (SVR)]. Blood pressure may not fall if
there is increase in peripheral vascular resistance
in the presence of decreased cardiac output,
resulting in inadequate flow to the tissue or global
tissue hypoperfusion. The insensitivity of blood
pressure to detect global tissue hypoperfusion has
been repeatedly confirmed. Thus, shock may
occur with a normal blood pressure, and
hypotension may occur without shock.
The onset of shock provokes a myriad of
autonomic responses, many of which serve to
maintain perfusion pressure to vital organs.
Stimulation of the carotid baroreceptor stretch
reflex activates the sympathetic nervous system
leading to
(1) Arteriolar vasoconstriction, resulting in
redistribution of blood flow from the skin,
skeletal muscle, kidneys, and splanchnic
viscera;
(2) an increase in heart rate and contractility
that increases cardiac output;
(3) constriction of venous capacitance
vessels, which augments venous return;
(4) release of the vasoactive hormones
epinephrine, norepinephrine, dopamine,
and cortisol to increase arteriolar and
venous tone; and
(5) release of antidiuretichormone and
activation of the renin-angiotensin axis to
enhance water and sodium conservation to
maintain intravascular volume. These
compensatory mechanisms attempt to
maintain Do2 to the most critical organs-
the coronary and cerebral circulation.
During this process, blood flow to other
organs such as the kidneys and
gastrointestinaltract may be compromised.
The cellular response to decreased Do2
is adenosine triphosphate depletion leading to ion-
pump dysfunction, influx of sodium, efflux of
potassium, and reduction in membrane resting
potential. Cellular edema occurs secondary to
increased intracellular sodium, while cellular
membrane receptors become poorly responsive
to the stress hormones insulin, glucagon, cortisol,
and catecholamines.
As shock progresses, lysosomal enzymes
are released into the cells with subsequent
hydrolysis of membranes, deoxyribonucleic acid,
ribonucleic acid, and phosphate esters. As the
cascade of shock continues, the loss of cellular
integrity and the breakdown in cellular
homeostasis result in cellular death. These
pathologic events give rise to the metabolic
features of hemoconcentration, hyperkalemia,
hyponatremia, prerenal azotemia, hyper- or
hypoglycemia, and lactic acidosis.
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Effects of inadequate perfusion on cell function.
In the early phases of septic shock, these physiologic changes produce a clinical syndrome called
the systemic inflammatory response syndrome or SIRS, defined as the presence of two or more of the
following features:
(1) Temperature greater than 38°C (100.4°F) or less than 36°C (96.8°F);
(2) Heart rate faster than 90 beats/min;
(3) Respiratory rate faster than 20 breaths/min;
(4) White blood cell count greater than 12.0 X 109/L, less than 4.0 X 109/L, or with greater than 10
percent immature forms or bands.(7)
As SIRS progresses, shock ensues, followed by multi organ dysfunction syndrome (MODS)
manifested by myocardial depression, adult respiratory distress syndrome, disseminated intravascular
coagulation, hepatic failure, or renal failure.
Figure (2)Mechanism of organ dysfunction in sepsis
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The fulminate progression from SIRS to
MODS is determined by the balance of anti-
inflammatory and pro inflammatory mediators
or cytokines that are released from endothelial
cell disruption Global tissue hypoperfusion alone
can independently activate the inflammatory
response and serve as a co morbid variable in the
pathogenesis of all forms of shock.(8) The failure
to diagnose and treat global tissue hypoperfusion
in a timely manner leads to an accumulation of
an oxygen debt, the magnitude of which correlates
with increased mortality.
There are four stages of shock
As it is a complex and continuous condition there
is no sudden transition from one stage to the
next.(9) At a cellular level, shock is the process
of oxygen demand becoming greater than oxygen
supply.(10)
Initial
During this stage, the state of hypoperfusion
causes hypoxia. Due to the lack of oxygen, the
cells perform lactic acid fermentation. Since
oxygen, the terminal electron acceptor in the
electron transport chain, is not abundant, this
slows down entry of pyruvate into the Krebs
cycle, resulting in its accumulation. Accumulating
pyruvate is converted to lactate by lactate
dehydrogenase and hence lactate accumulates
(causing lactic acidosis) figure (1).
Compensatory
This stage is characterised by the body employing
physiological mechanisms, including neural,
hormonal and bio-chemical mechanisms in an
attempt to reverse the condition. As a result of
the acidosis, the person will begin to
hyperventilate in order to rid the body of carbon
dioxide (CO2). CO2 indirectly acts to acidify the
blood and by removing it the body is attempting
to raise the pH of the blood. The baroreceptors in
the arteries detect the resulting hypotension, and
cause the release of epinephrine and
norepinephrine. Norepinephrine causes
predominately vasoconstriction with a mild
increase in heart rate, whereas epinephrine
predominately causes an increase in heart rate
with a small effect on the vascular tone; the
combined effect results in an increase in blood
pressure. The renin-angiotensin axis is activated,
and arginine vasopressin (Anti-diuretic hormone;
ADH) is released to conserve fluid via the
kidneys. These hormones cause the
vasoconstriction of the kidneys, gastrointestinal
tract, and other organs to divert blood to the heart,
lungs and brain. The lack of blood to the renal
system causes the characteristic low urine
production. However the effects of the renin-
angiotensin axis take time and are of little
importance to the immediate homeostatic
mediation of shock.
Progressive
Should the cause of the crisis not be successfully
treated, the shock will proceed to the progressive
stage and the compensatory mechanisms begin
to fail. Due to the decreased perfusion of the cells,
sodium ions build up within while potassium ions
leak out. As anaerobic metabolism continues,
increasing the body's metabolic acidosis, the
arteriolar smooth muscle and precapillary
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Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
sphincters relax such that blood remains in the
capillaries.(11) Due to this, the hydrostatic
pressure will increase and, combined with
histamine release, this will lead to leakage of fluid
and protein into the surrounding tissues. As this
fluid is lost, the blood concentration and viscosity
increase, causing sludging of the micro-
circulation. The prolonged vasoconstriction will
also cause the vital organs to be compromised
due to reduced perfusion.(11) If the bowel
becomes sufficiently ischemic, bacteria may enter
the blood stream, resulting in the increased
complication of endotoxic shock.(11,12)
Refractory
At this stage, the vital organs have failed and the
shock can no longer be reversed. Brain damage
and cell death are occurring, and death will occur
imminently. One of the primary reasons that shock
is irreversible at this point is that much cellular
ATP has been degraded into adenosine in the
absence of oxygen as an electron receptor in the
mitochondrial matrix. Adenosine easily perfuses
out of cellular membranes into extracellular fluid,
furthering capillary vasodilation, and then is
transformed into uric acid. Because cells can only
produce adenosine at a rate of about 2% of the
cell's total need per hour, even restoring oxygen
is futile at this point because there is no adenosine
to phosphorylate into ATP.(12)
Diagnosis
Signs and symptoms: The presentation of shock
is variable with some people having only minimal
symptoms such as confusion and weakness.(13)
While the general signs for all types of shock are
low blood pressure, decreased urine output, and
confusion these may not always be present.(14)
While a fast heart rate is common, those on ?-
blockers, those who are athletic and in 30% of
cases those with shock due to intra abdominal
bleeding may have a normal or slow heart rate.
Direct loss of effective circulating blood volume
leading to:
• A rapid, weak, thready pulse due to decreased
blood flow combined with tachycardia
• Cool, clammy skin due to vasoconstriction .
• Rapid and shallow breathing due to
sympathetic nervous system stimulation and
acidosis
• Hypothermia due to decreased perfusion and
evaporation of sweat
• Thirst and dry mouth, due to fluid depletion
• Cold and mottled skin , especially
extremities, due to insufficient perfusion of
the skin
The shock index (SI), defined as heart rate
divided by systolic blood pressure, is an accurate
diagnostic measure that is more useful than
hypotension and tachycardia in isolation.(15)
Under normal conditions, a number between 0.5
and 0.8 is typically seen. Should that number
increase, so does suspicion of an underlying state
of shock. Blood pressure alone may not be a
reliable sign for shock, as there are times when a
person is in circulatory shock but has a stable
blood pressure.(12)
Empirical criteria for diagnosis of circulatory
shock regardless of the cause ,four of these six
criteria should be met(16) :
1. Ill appearance or altered mental status.
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2. Heart rate> 100 beat/min .
3.Respiratory rate >20 cycle/min .or paco2< 32
mm/hg
4.serum lactate level > 4 mmol/L.
5.Arterial base deficit ? -4meq/L.
6.Arterial hypotension> 20 minutes duration .
The first changes seen in shock is an
increased cardiac output followed by a decrease
in mixed venous oxygen saturation (SmvO2) as
measured in the pulmonary artery via a pulmonary
artery catheter. Central venous oxygen saturation
(ScvO2) as measured via a central line correlates
well with SmvO2 and are easier to acquire. If
shock progresses anaerobic metabolism will begin
to occur with an increased blood lactic acid as
the result. While many laboratory tests are
typically performed there is no test that either
makes or excludes the diagnosis. A chest X-ray
or emergency department ultrasound may be
useful to determine volume state.
Differential diagnosis (17)
Shock is a common end point of many medical
conditions. It has been divided into four main
types based on the underlying cause:
hypovolemic, distributive, cardiogenic and
obstructive. A few additional classifications are
occasionally used including: endocrinologic
shock.
Hypovolemic: This is the most common type of
shock and is caused by insufficient circulating
volume. Its primary cause is hemorrhage (internal
and/or external), or loss of fluid from the
circulation. Vomiting and diarrhea are the most
common cause in children.. With other causes
including burns, environmental exposure and
excess urine loss due to diabetic ketoacidosis and
diabetes insipidus.
Table (I): Classes of hemorrhage.
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Cardiogenic
This type of shock is caused by the failure of the
heart to pump effectively. This can be due to
damage to the heart muscle, most often from a
large myocardial infarction. Other causes of
cardiogenic shock include dysrhythmias,
cardiomyopathy/myocarditis, congestive heart
failure (CHF), or cardiac valve problems.
Obstructive
Obstructive shock is due to obstruction of blood
flow outside of the heart.(18)Several conditions
can result in this form of shock.
• Cardiac tamponade in which fluid in the
pericardium prevents inflow of blood into
the heart (venous return). Constrictive
pericarditis, in which the pericardium
shrinks and hardens, is similar in
presentation.
• Tension pneumothorax Through increased
intrathoracic pressure, blood flow to the
heart is prevented (venous return).
• Pulmonary embolism is the result of a
thromboembolic incident in the blood
vessels of the lungs and hinders the return
of blood to the heart.
• Aortic stenosis hinders circulation by
obstructing the ventricular outflow tract
Distributive
Distributive shock is due to impaired
utilization of oxygen and thus production of
energy by the cell. Examples of this form of shock
are:
• Septic shock is the most common cause of
distributive shock.(19) Caused by an
overwhelming systemic infection resulting
in vasodilation leading to hypotension.
Septic shock can be caused by Gram
negative bacteria such as (among others)
Escherichia coli, Proteus species, Klebsiella
pneumoniae which release an endotoxin
which produces adverse biochemical,
immunological and occasionally
neurological effects which are harmful to
the body, and other Gram-positive cocci,
such as pneumococci and streptococci, and
certain fungi as well as Gram-positive
bacterial toxins.
Septic shock also includes some elements
of cardiogenic shock. Septic shock can be defined
as "sepsis-induced hypotension (systolic blood
pressure <90 mm Hg or a reduction of 40 mm Hg
from baseline) despite adequate fluid resuscitation
along with the presence of perfusion
abnormalities that may include, but are not limited
to, lactic acidosis, oliguria, or an acute alteration
in mental status. Patients who are receiving
inotropic or vasopressor agents may have a
normalized blood pressure at the time that
perfusion abnormalities are identified.
Figure (1) petechial haemorrhage
in case of sepsis.
Early detection(20)
The qSOFA Score was introduced by the
Sepsis-3 group in February 2016 as a simplified
version of the SOFA Score as an initial way to
screen for sepsis.
The qSOFA Score is an easy to use and
apply score to help as an initial screening tool for
poor outcome in infection patients.
qSOFA, ie, alteration in mental status, systolic
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blood pressure ?100 mm Hg, or respiratory rate
>22/min.
septic shock
• can be identified with a clinical construct
of sepsis with persisting hypotension
requiring vasopressors to maintain MAP
>65 mm Hg and having a serum lactate
level >2 mmol/L (18 mg/dL) despite
adequate volume resuscitation.
• With these criteria, hospital mortality is
in excess of 40%.
Figure (3) new definition of sepsis according to
The Third International Consensus Definitions
for Sepsis and Septic Shock (Sepsis-3).
• Anaphylactic shock (17,67) :
Anaphylaxis is a severe, life-threatening,
generalized or systemic hypersensitivity reaction.
Characterized by rapidly developing life-
threatening airway and or breathing and or
circulation problems usually associated with skin
and mucosal changes.
Figure (2,3) show skin and mucosal changes
with anaphylaxis
Caused by a severe anaphylactic reaction to an
allergen, antigen, drug or foreign protein causing
the release of histamine which causes widespread
vasodilation, leading to hypotension and
increased capillary permeability.
• Neurogenic shock: High spinal injuries
may cause neurogenic shock.(21) The classic
symptoms include a slow heart rate due to loss of
cardiac sympathetic tone and warm skin due to
dilation of the peripheral blood vessels. (This term
can be confused with spinal shock which is a
recoverable loss of function of the spinal cord
after injury and does not refer to the
haemodynamic instability per se.)
Cervical spine MRI of a patient with SCI: C4
fracture and dislocation, spinal cord
compression
Low blood pressure occurs due to
decreased systemic vascular resistance resulting
in pooling of blood within the extremities lacking
sympathetic tone. The slowed heart rate results
from unopposed vagal activity and has been found
to be exacerbated by hypoxia and endobronchial
suction.(22) Neurogenic shock can be a potentially
devastating complication, leading to organ
dysfunction and death if not promptly recognized
and treated. It is not to be confused with spinal
shock, which is not circulatory in nature.
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23
Causes: Neurogenic shock can result
from severe central nervous system damage (brain
injury, cervical or high thoracic spinal cord). (23)
In more simple terms: the trauma causes a sudden
loss of background sympathetic stimulation to the
blood vessels. This causes them to relax
(vasodilation) (24) resulting in a sudden decrease
in blood pressure (secondary to a decrease in
peripheral vascular resistance).Neurogenic shock
results from damage to the spinal cord above the
level of the 6th thoracic vertebra. (25) It is found
in about half of people who suffer spinal cord
injury within the first 24 hours, and usually doesn't
go away for one to three weeks. (25)
Endocrine: Based on endocrine disturbances such
as: (26)
• Hypothyroidism (Can be considered a
form of Cardiogenic shock) in critically ill
patients, reduces cardiac output and can lead to
hypotension and respiratory insufficiency.
• Thyrotoxicosis (Cardiogenic shock)
• may induce a reversible
cardiomyopathy.
• Acute adrenal insufficiency (Distributive
shock) is frequently the result of discontinuing
corticosteroid treatment without tapering the
dosage. However, surgery and inter current
disease in patients on corticosteroid therapy
without adjusting the dosage to accommodate for
increased requirements may also result in this
condition.
• Relative adrenal insufficiency
(Distributive shock) in critically ill patients where
present hormone levels are insufficient to meet
the higher demands
Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
Initial Approach to the Patient in
Shock(27)
As any critically ill patient follow ABCDE
approach in our management (airway, breathing,
circulation, disability, and exposure). Early,
adequate hemodynamic support of patients in
shock is crucial to prevent worsening organ
dysfunction and failure. Resuscitation should be
started even while investigation of the cause is
ongoing. Once identified, the cause must be
corrected rapidly (e.g., control of bleeding,
percutaneous coronary intervention for coronary
syndromes, thrombolysis or embolectomy for
massive pulmonary embolism, and administration
of antibiotics and source control for septic shock).
Unless the condition is rapidly reversed, an
arterial catheter should be inserted for monitoring
of arterial blood pressure and blood sampling,
plus a central venous catheter for the infusion of
fluids and vasoactive agents and to guide fluid
therapy.
The initial management of shock is problem-
oriented, and the goals are therefore the same,
regardless of the cause, although the exact
treatments that are used to reach those goals may
differ. A useful mnemonic to describe the
important components of resuscitation is the VIP
rule(28) : ventilate (oxygen administration),
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infuse (fluid resuscitation), and pump
(administration of vasoactive agents).
Ventilatory Support
The administration of oxygen should be started
immediately to increase oxygen delivery and
prevent pulmonary hypertension. Pulse oximetry
is often unreliable as a result of peripheral
vasoconstriction, and precise determination of
oxygen requirements will often require blood gas
monitoring. Mechanical ventilation by means of
a mask rather than endotracheal intubation has a
limited place in the treatment of shock because
technical failure can rapidly result in respiratory
and cardiac arrest. Hence, endotracheal intubation
should be performed to provide invasive
mechanical ventilation in nearly all patients with
severe dyspnea, hypoxemia, or persistent or
worsening acidemia (pH, <7.30).
Invasive mechanical ventilation has the
additional benefits of reducing the oxygen
demand of respiratory muscles and decreasing left
ventricular afterload by increasing trathoracic
pressure. An abrupt decrease in arterial pressure
after the initiation of invasive mechanical
ventilation strongly suggests hypovolemia and a
decrease in venous return.The use of sedative
agents should be kept to a minimum to avoid
further decreases in arterial pressure and cardiac
output.
Fluid Resuscitation
Fluid therapy to improve microvascular
bloodflow and increase cardiac output is an
essential part of the treatment of any form of
shock. Even patients with cardiogenic shock may
benefit from fluids, since acute edema can result
in a decrease in the effective intravascular volume.
However, fluid administration should be closely
monitored, since too much fluid carries the risk
of edema with its unwanted consequences.
Pragmatic end points for fluid resuscitation are
difficult to define. In general, the objective is for
cardiac output to become preload-
independent(i.e., on the plateau portion of the
Frank-Starling curve), but this is difficult to assess
clinically.
In patients receiving mechanical ventilation,
signs of fluid responsiveness may be identified
either directly from beat-by-beat stroke-volume
measurements with the use of cardiac-output
monitors or indirectly from observed variations
in pulse pressure on the arterial-pressure tracing
during the ventilator cycle. However, such
bedside inferences have some limitations(29)-
notably, that the patient must receive ventilation
with relatively large tidal volumes, have no
spontaneous breathing effort (which usually
requires the administration of sedatives or even
muscle relaxants),and be free of major arrhythmia
and right ventricular dysfunction. A passive leg-
raising test is an alternative method(30) but
requires a rapid response device, since the effect
is transient. Regardless of the test used, there
remains a gray zone in which it is difficult to
predict a patient's response to intravenous fluids.
A fluid-challenge technique should be used to
determine a patient's actual response to fluids,
while limiting the risks of adverse effects. A fluid
challenge incorporates four elements that should
be defined in advance. (31)
• First, the type of fluid must be selected.
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Crystalloid solutions are the first choice, because
they are well tolerated and cheap. The use of
albumin to correct severe hypoalbuminemia may
be reasonable in some patients.(32)
• Second, the rate of fluid administration
must be defined. Fluids should be infused rapidly
to induce a quick response but not so fast that an
artificial stress response develops; typically, an
infusion of 300 to 500 ml of fluidis administered
during a period of 20 to 30 minutes. (33)
• Third, the objective of the fluid challenge
must be defined. In shock, the objective is usually
an increase in systemic arterial pressure, although
it could also be a decrease in heart rate or an
increase in urine output.
• Finally, the safety limits must be defined.
Pulmonary edema is the most serious
complication of fluid infusion. Although it is not
a perfect guideline, a limit in central venous
pressure of a few millimeters of mercury above
the baseline value is usually set to prevent fluid
overload. (34)
Stimulation of the patient and any other
change in therapy should be avoided during the
test. Fluid challenges can be repeated as required
but must be stopped rapidly in case of non-
response n order to avoid fluid overload.
Vasoactive Agents
Vasopressors
If hypotension is severe or if it persists
despite fluid administration, the use of
vasopressors is indicated. It is acceptable practice
to administer a vasopressor temporarily while
fluid resuscitation is ongoing, with the aim of
discontinuing it, if possible, after hypovolemia
has been corrected.
Adrenergic agonists are the first-line vasopressors
because of their rapid onset of action, high
potency, and short half-life, which allows easy
dose adjustment. Stimulation of each type of
adrenergic receptor has potentially beneficial and
harmful effects. For example, β -adrenergic
stimulation can increase blood flow but also
increases the risk of myocardial ischemia as a
result of increased heart rate and contractility.
Hence, the use of isoproterenol, a pure α -
adrenergic agent, is limited to the treatment of
patients with severe bradycardia.
At the other extreme, β -adrenergic
stimulation will increase vascular tone and blood
pressure but can also decrease cardiac output and
impair tissue blood flow, especially in the
hepatosplanchnic region. For this reason,
phenylephrine, an almost pure ?-adrenergic agent,
is rarely indicated.
We consider norepinephrine to be the
vasopressor of first choice; it has predominantly
β-adrenergic properties, but its modest α-
adrenergic effects help to maintain cardiac output.
Administration generally results in a clinically
significant increase in mean arterial pressure, with
little change in heart rate or cardiac output. The
usual dose is 0.1 to 2.0 μ g per kilogram of body
weight per minute.
Dopamine has predominantly β -
adrenergic effects at lower doses and α -adrenergic
effects at higher doses, but its effects are relatively
weak. Dopaminergic effects at very low doses (<3
μg per kilogram per minute, given intravenously)
may selectively dilate the hepatosplanchnic and
renal circulations, but controlled trials have not
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shown a protective effect on renal function,(35)
and its routine use for this purpose is no longer
recommended.
Dopaminergic stimulation may also have
undesired endocrine effects on the hypothalamic-
pituitary system, resulting in immunosuppression,
primarily through a reduction in the release of
prolactin.
In a recent randomized, controlled, double
blind trial, dopamine had no advantage over
norepinephrine as the first-line vasopressor agent;
moreover, it induced more arrhythmias and was
associated with an increased 28-day rate of death
among patients with cardiogenic shock.(36)
Administration of dopamine, as compared with
norepinephrine, may also be associated with
higher rates of death among patients with
septicshock.(37)Hence, we no longer recommend
dopamine for the treatment of patients with shock.
Epinephrine, which is a stronger agent, has
predominantly β -adrenergic effects at low doses,
with α -adrenergic effects becoming more
clinically significant at higher doses. However,
epinephrine administration can be associated with
an increased rate of arrhythmia(38,39)and a
decrease in splanchnic blood flow(38)and can
increase blood lactate levels, probably by
increasing cellular metabolism.(38,40)
Prospective, randomized studies have not
shown any beneficial effects of epinephrine over
norepinephrine in septic shock.(39,40)We reserve
epinephrine as a second-line agent for severe
cases. (34)
The use of other strong vasopressor agents
as ontinuous infusions (e.g., angiotensin or
metaraminol)has largely been abandoned.
Non selective inhibition of nitric oxide has
not been shown to be beneficial in patients with
cardiogenic shock(41)and is detrimental in
patients with septic shock. (42)
Vasopressin deficiency can develop in
patients with very hyperkinetic forms of
distributive shock, and the administration of low-
dose vasopressin may result in substantial
increases in arterial pressure. In the Vasopressin
and SepticShock Trial (VASST), investigators
found that the addition of low-dose vasopressin
to norepinephrine in the treatment of patients with
septic shock was safe(43)and may have been
associated with a survival benefit for patients with
forms of shock that were not severe and for those
who also received glucocorticoids. (44)
Vasopressin should not be used at doses higher
than 0.04 U per minute and should be
administered only in patients with a high level of
cardiac output.
Terlipressin, an analogue of vasopressin,
has a duration of action of several hours, as
compared with minutes for vasopressin. For this
reason, we do not believe it offers an advantage
over vasopressin in the ICU. Vasopressin
derivatives with more selective V1-receptor
activity are currently being studied.
Inotropic Agents
We consider dobutamine to be the inotropic agent
of choice for increasing cardiac output, regardless
of whether norepinephrine is also being given.
With predominantly β -adrenergic properties
,dobutamine is less likely to induce tachycardia
than isoproterenol. An initial dose of just a few
micrograms per kilogram per minute may
27
Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
substantially increase cardiac output. Intravenous
doses in excess of 20 μ g per kilogram per minute
usually provide little additional benefit.
Dobutamine has limited effects on arterial
pressure, although pressure may increase slightly
in patients with myocardial dysfunction as the
primary abnormality or may decrease slightly in
patients with underlying hypovolemia. Instead of
routine administration of a fixed dose of
dobutamine to increase oxygen delivery to
supranormal, predetermined levels, the dose
should be adjusted on an individual basis to
achieve adequate tissue perfusion. Dobutamine
may improve capillary perfusion in patients with
septic shock, independent of its systemic effects.
(45)Phosphodiesterase type III inhibitors, such as
milrinone and enoximone, combine inotropic and
vasodilating properties.
By decreasing the metabolism of cyclic
AMP, these agents may reinforce the effects of
dobutamine. They may also be useful when β-
adrenergic receptors are down regulated or in
patients recently treated with beta-blockers.
However, phosphodiesterase typeIII inhibitors
may have unacceptable adverse effects in patients
with hypotension, and the long half-lives of these
agents (4 to 6 hours) prevent minute-to-minute
adjustment. Hence, intermittent, short-term
infusions of small doses of phosphodiesterase III
inhibitors may be preferable to a continuous
infusion in shock states. Levosimendan, a more
expensive agent, acts primarily by binding to
cardiac troponin C and increasing the calcium
sensitivity of myocytes, but it also acts as a
vasodilator by opening ATP sensitive potassium
channels in vascular smoothmuscle. However,
this agent has a half-life of several days, which
limits the practicality of its use in acute shock
states.
Vasodilators
By reducing ventricular after load,
vasodilating agents may increase cardiac output
without increasing myocardial demand for
oxygen. The major limitation of these drugs is
the risk of decreasing arterial pressure to a level
that compromises tissue perfusion. Nevertheless,
in some patients, prudent use of nitrates and
possibly other vasodilators may improve
microvascular perfusion and cellular function.
(46)
Mechanical Support
Mechanical support with intraaortic
balloon counterpulsation (IABC) can reduce left
ventricular afterload and increase coronary blood
flow. However, a recent randomized, controlled
tria lshowed no beneficial effect of IABC in
patients with cardiogenic shock,(47)and its
routine use in cardiogenic shock is not currently
recommended.
Venoarterial extracorporeal membrane
oxygenation(ECMO) may be used as a temporary
lifesaving measure in patients with reversible
cardiogenicshock or as a bridge to heart
transplantation. (48)
Goals of Hemodynamic Support
Arterial Pressure
The primary goal of resuscitation should be not
only to restore blood pressure but also to provide
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Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
adequate cellular metabolism, for which the
correction of arterial hypotension is a prerequisite.
Restoring a mean systemic arterial pressure of65
to 70 mm Hg is a good initial goal, but the level
should be adjusted to restore tissue perfusion,
assessed on the basis of mental status, skin
appearance, and urine output, as described above.
In patients with oliguria, in particular, the effects
of a further increase in arterial pressure on urine
output should be assessed regularly, unless acute
renal failure is already established. Conversely, a
mean arterial pressure lower than 65 to 70 mm
Hg may be acceptable in a patient with acute
bleeding who has no major neurologic problems,
with the aim of limiting blood loss and associated
coagulopathy, until the bleeding is controlled.
Cardiac Output and Oxygen Delivery
Since circulatory shock represents an
imbalance between oxygen supply and oxygen
requirements, maintaining adequate oxygen
delivery to the tissues is essential, but all the
strategies to achieve this goal have limitations.
After correction of hypoxemia and severe anemia,
cardiac output is the principal determinant of
oxygen delivery, but the optimal cardiac output is
difficult to define. Cardiac output can be measured
by means of various techniques, each of which has
its own benefits and drawbacks(49).Absolute
measures of cardia coutput are less important than
monitoring trends in response to interventions such
as a fluid challenge.
The targeting of a predefined cardiac
output is not advisable, since the cardiac output
that is needed will vary among patients and in
the same patient over time. Measurements of
mixed venous oxygen saturation(SvO2) may be
helpful in assessing the adequacy of the balance
between oxygen demandand supply; SvO2
measurements are also very useful in the
interpretation of cardiac output.(50) SvO2 is
typically decreased in patients with low-flow
states or anemia but is normal or high in those
with distributive shock. Its surrogate,
central venous oxygen saturation (ScvO2), which
is measured in the superior vena cava by means
of a central venous catheter, reflects the oxygen
saturation of the venous blood from the upperhalf
of the body only. Under normal circumstances,
ScvO2 is slightly less than SvO2, but in critically
ill patients it is often greater. Rivers et al. (51)
found that in patients presenting to the emergency
department with septic shock, a treatment
algorithm targeting an ScvO2 of at least 70%
during the first 6 hours was associated with
decreased rates of death. The robustness of this
finding is currently being evaluated in three
multicenter trials. (ClinicalTrials.gov numbers,
NCT00975793and NCT00510835; and Current
Controlled Trials number, ISRCTN36307479).
Blood Lactate Level
An increase in the blood lactate level
reflects abnormal cellular function. In low-flow
states, theprimary mechanism of hyperlactatemia
is tissue hypoxia with development of anaerobic
metabolism, but in distributive shock, the
pathophysiology is more complex and may also
involve increased glycolysis and inhibition of
pyruvate dehydrogenase.
In all cases, alterations in clearance can
be due to impaired liver function.The value of
29
Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
serial lactate measurements in the management
of shock has been recognized for 30 years. (52)
Although changes in lactate take place more
slowly than changes in systemic arterial pressure
or cardiac output, the blood lactate level should
decrease over a period of hours with effective
therapy. In patients with shock and a blood lactate
level of more than 3 mmol per liter, Jansen et al.
(46) found that targeting a decrease of at least
20% in the blood lactate level over a 2-hour period
seemed to be associated with reduced in-hospital
mortality.
Microcirculatory Variables
The development of hand held devices for
orthogonalpolarization spectral (OPS) imaging
and its successor, side stream dark-field (SDF)
imaging, is providing new means of directly
visualizing the microcirculation and evaluating
the effects of interventions on microcirculatory
flow in easily accessible surfaces, such as the
sublingual area. (53) Microcirculatory changes,
including decreased capillary density, a reduced
proportion of perfused capillaries, and increased
heterogeneity of blood flow, have been identified
in various types of circulatory shock , and the
persistence of these alterations is associated with
worse outcomes. (54)
Near-infrared spectroscopy is a technique
that uses near-infrared light to determine tissue
oxygen saturation from the fractions of
oxyhemoglobin and deoxyhemoglobin. Analysis
of the changes in tissue oxygen saturation during
a brief episode of forearm ischemia can be used
to quantify micro vascular dysfunction(55); such
alterations are associated with worse
outcomes.(56)
Various therapeutic interventions have
been shown to have an effect on these
microcirculatory variables, but whether therapy
that is guided by monitoring or targeting the micro
circulation can improve outcomes requires further
study and cannot be recommended at this time.
Therapeutic Priorities and Goals
There are essentially four phases in the
treatmentof shock, and therapeutic goals and
monitoringneed to be adapted to each phase .
• In thefirst (salvage) phase, the goal of
therapy is to achieve a minimum blood pressure
and cardiac output compatible with immediate
survival. Minimal monitoring is needed; in most
cases, invasive monitoring can be restricted to
arterial and central venous catheters. Lifesaving
procedures (e.g.,surgery for trauma, pericardial
drainage, revascularization for acute myocardial
infarction, and antibioticsfor sepsis) are needed
to treat the underlying cause.
• In the second (optimization) phase, the goal
is to increase cellular oxygen availability, and there
is a narrow window of opportunity for intervention
stargeting hemo dynamic status. (51) Adequate
hemodynamic resuscitation reduces inflammation,
mitochondrial dysfunction, and caspase activation.
(57,58) Measurements of SvO2 and lactate levels
may help guide therapy, and monitoring of cardiac
output should be considered.
• In the third(stabilization) phase, the goal
is to prevent organ dysfunction, even after
hemodynamic stability has been achieved.
Oxygen supply to the tissues is no longer the key
problem, and organ support becomes more
relevant.
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Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
• Finally, in the fourth (de escalation) phase,
the goal is to wean the patient from vasoactive
agents and promote spontaneous polyuria or
provoke fluid elimination through the use of
diuretics or ultra filtration to achieve a negative
fluid balance.
Treatment goals
The goal of treatment is to achieve a urine
output of greater than 0.5 ml/kg/h, a central
venous pressure of 8-12 mmHg and a mean
arterial pressure of 65-95 mmHg. In trauma the
goal is to stop the bleeding which in many cases
requires surgical interventions.
For those with haemorrhagic shock the
current evidence supports limiting the use of
fluids for penetrating thorax and abdominal
injuries allowing mild hypotension to persist
(known as permissive hypotension).(59)Targets
include a mean arterial pressure of 60 mmHg, a
systolic blood pressure of 70-90 mmHg.(60) or
until their adequate mentation and peripheral
pulses.(60)
Specific treatment for different type of shock
31
Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
Management Hypovolemic shock:
Management may include securing the
airway via intubation to decrease the work of
breathing, oxygen supplementation, intravenous
fluids and blood transfusions. It is important to
keep the person warm as well as adequately
manage pain and anxiety as these can increase
oxygen consumption.
Fluids Aggressive intravenous fluids are
recommended in most types of shock (e.g. 1-2
liter normal saline bolus over 10 minutes or 20ml/
kg in a child) which is usually instituted as the
person is being further evaluated(61) Which
intravenous fluid is superior, colloids or
crystalloids, remains undetermined. Thus as
crystalloids are less expensive they are
recommended.
If the person remains in shock after initial
resuscitation packed red blood cells should be
administered to keep the hemoglobin greater than
10gms/l. For those with hemorrhagic shock the
current evidence supports limiting the use of
fluids for penetrating thorax and abdominal
injuries allowing mild hypotension to persist
(known as permissive hypotension). (62) Targets
include a mean arterial pressure of 60 mmHg, a
systolic blood pressure of 70-90 mmHg, or until
their adequate mentation and peripheral pulses.
Medications Vasopressors may be
used if blood pressure does not improve with
fluids. There is no evidence of superiority of one
vasopressor over another. (63) Vasopressors have
not been found to improve outcomes when used
for hemorrhagic shock from trauma, but may be
of use in neurogenic shock. Activated protein C
(Xigris) while once aggressively promoted for the
management of septic shock has been found to
improve survival ,thus recommended. (64) The
use of sodium bicarbonate is controversial as it
has not been shown to improve outcomes. (65)
If used at all it should only be considered if the
pH is less than 7.0.
Figure (3) show The main pathophysiological
mechanisms involved in acute traumatic
coagulopathy and transfusion strategy. SAP,
systolic arterial pressure; RBC, red blood cells;
FFP, fresh-frozen plasma(66).
Septic shock:(20) The leadership of the
Surviving Sepsis Campaign (SSC) has believed
since its inception that both the SSC Guidelines
and the SSC performance improvement indicators
will evolve as new evidence that improves our
32
Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
understanding of how best to care for patients with septic shock the SSC Executive Committee has
revised the improvement bundles as follows:
Anaphylaxis(67)
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Narayana Medical Journal Volume-6 | Issue-1 | January-June 2017
Cardiogenic shock
Cardiogenic shock is defined by sustained
low blood pressure with tissue hypo perfusion
despite adequate left ventricular filling pressure.
Signs of tissue hypoperfusion include low urine
production (<30 mL/hour), cool extremities, and
altered level of consciousness.
Treatment of cardiogenic shock depends
on the cause. If cardiogenic shock is due to a heart
attack, attempts to open the heart's arteries may
help. An intra-aortic balloon pump or left
ventricular assist device may improve matters
until this can be done. Medications that improve
the heart's ability to contract (positive inotropes)
may help; however, it is unclear which is best.
Norepinephrine may be better if the blood
pressure is very low whereas dopamine or
dobutamine may be more useful if only slightly
low.(68)
Treatment of Neurogenic shock
• Dopamine (Intropin) is often used either
alone or in combination with other inotropic
agents.
• Vasopressin (antidiuretic hormone
[ADH])(69)
• Certain vasopressors (ephedrine,
norepinephrine). Phenylephrine may be used as
a first line treatment, or secondarily in people who
do not respond adequately to dopamine.
• Atropine is administered for slowed heart
rate.(70)
Conclusions
Circulatory shock is associated with high
morbidity and mortality. Prompt identification is
essential so that aggressive management can be
started. Appropriate treatment is based on a good
understanding of the underlying
pathophysiological mechanisms. Treatment
should include correction of the cause of shock
and hemodynamic stabilization, primarily through
fluid infusion and administration of vasoactive
agents. The patient's response can be monitored
by means of careful clinical evaluation and blood
lactate measurements;
microvascular evaluation may be feasible in the
future.
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List of Abbreviations
(a-v)CO2 Arterial-central venous carbon dioxide
difference
Cao2 Arterial oxygen content
Cmvo2 Mixed venous oxygen content
CI Cardiac index (cardiac output/body surface
area)
CO Cardiac output
CPP Coronary perfusion pressure
CVP Central venous pressure
Do2 Systemic oxygen delivery
DBP Diastolic blood pressure
Hb Hemoglobin
MAP Mean arterial pressure
MODS Multi organ dysfunction syndrome
OER Oxygen extraction ratio
Paco2 Arterial carbon dioxide pressure
Pao2 Arterial oxygen pressure
PAOP Pulmonary artery occlusion (wedge)
pressure
Sao2 Arterial oxygen saturation
Scvo2 Central venous oxygen saturation
Smvo2 Mixed venous oxygen saturation
(pulmonary artery)
Srvo2 Retinal venous oxygen saturation
SIRS Systemic inflammatory response syndrome
SVR Systemic vascular resistance
Vo2 Systemic oxygen consumption
39
... Th e main challenge lies in the diagnosis of the disease, diff erent treatment protocols, multiple risk factors, etiology, and outcomes. In this connection, the question arises regarding an integrated approach to the study of this condition and the development of recommendations for the management of patients of this kind, which served as the purpose of this manuscript [4]. ...
... It includes deaths that occur due to complications of the pregnancy (direct deaths), and those resulting from worsening of other disease processes due to the pregnancy (indirect deaths). Deaths that occur from causes completely unrelated to pregnancy or birth are termed incidental deaths, and are not included in calculation of the MMR [4]. ...
... Additionally, postpartum infections can be treated using antibiotics. In fact, the use of broad-spectrum antibiotics both for the prevention and treatment of maternal infection is common in low-income countries [5,4]. Maternal death due to eclampsia can also be prevented through the use of medications such as magnesium sulfate. ...
- Adel Hamed Elbaih
- Adnan Um Al-Nasser
Background: Maternal collapse occurs any time during pregnancy, up to 42 days following delivery and is an acute event involving cardiorespiratory systems and/or brain, resulting in impaired consciousness or death. Therefore, we aim to look into the common pitfalls that both medical students and new physicians face in the recognition, diagnosis, and management of these conditions. Targeted Population: Maternal collapse patients who are requiring urgent management in the ED, with Emergency Physicians for teaching approach protocol. Aim of the study: Appropriate for identifi cation of women at risk and review of maternal collapse with neonatal outcomes by training protocol to Emergency Physicians. Based on patients' causes of maternal collapse pregnant women. Methods: Collection of all possible available data about the Pregnancy in Maternal Collapse in the Emergency department. By many research questions to achieve these aims so a midline literature search was performed with the keywords "critical care", "emergency medicine", "principals of ACLS therapy in Pregnancy ", "ACLS and Maternal Collapse". Literature search included an overview of recent defi nition, causes and recent therapeutic strategies. Results: All studies introduced that the initial diagnosis of Pregnancy in Maternal Collapse and their therapy is a serious condition that face patients of the emergency and critical care departments. Conclusion: Emergency obstetric care to address the major causes of maternal death, Postnatal care which is the six weeks following delivery and Public health approach to decrease with addressing maternal mortality. Keywords: Maternal collapse; Pregnant women; Emergency physicians; Skill approach.
... Conventionally, there's four shock categories: hypovolemic, cardiogenic, obstructive, and distributive. Hypovolemic shock happens when intravascular volume is decreasing to the extent of cardiovascular failure [7,8]. The hypovolemic shock may result from extreme dehydration by a variety of mechanisms or from lack of blood. ...
... ICP is normally ≤ 15 mmHg in adults, and pathologic ICH is present at pressures ≥ 20 mm Hg. Homeostatic mechanisms stabilize ICP, with occasional transient elevations associated with physiologic events, including sneezing, coughing, or Valsalva maneuvers [5,8] (Table 1). ...
... Multiple causes have been identified that disturb the electrical function of the heart and cause sudden cardiac arrest, and they can be divided into two branches cardiac and non-cardiac causes. Cardiac causes can be further divided into non-structural and structural, with structural causes having two categories, ischemic and non-ischemic [9]. ...
- Adel Hamed Elbaih
Background: Sudden Cardiac Arrest (SCA) in pregnancy is a particularly challenging clinical condition. Although management and resuscitation of these patients are quite similar to other adult patients except for few modifications because of the changes of pregnancy, but the uniqueness of this situation lays in the fact that here you are dealing with two patients instead of one. Targeted Population: All Pregnancy patients who are requiring urgent management in the ED, with Emergency Physicians for teaching protocol. Aim of the Study: Appropriate knowledge and training for pregnancy patients by teaching protocol to Emergency Physicians. Methods: Collection of all possible available data about the pregnancy with cardiac arrest in the Emergency Department. By many research questions to achieve these aims so a midline literature search was performed with the keywords "critical care", "emergency medicine", "principals of resuscitation in pregnancy", "Maternal Collapse". Literature search included an overview of recent definition, causes and recent therapeutic strategies. Results: All studies introduced that the initial diagnosis of pregnancy with cardiac arrest and their therapy is a serious condition that face patients of the emergency and critical care departments. Conclusion: Appropriate knowledge and training for pregnancy patients by teaching protocol to Emergency Physicians are extremely important for a better outcome, since a poor resuscitation techniques and knowledge deficit are strongly linked to poorer outcomes. Keywords: Cardiac arrest in pregnancy; Emergency physicians; Protocol; SCA; SCD
... Conventionally, there's four shock categories: hypovolemic, cardiogenic, obstructive, and distributive. Hypovolemic shock happens when intravascular volume is decreasing to the extent of cardiovascular failure [7,8]. The hypovolemic shock may result from extreme dehydration by a variety of mechanisms or from lack of blood. ...
- Adel Hamed Elbaih
- Emad Amjad Abou
Background: Trauma continues to be the leading cause of death; responsible for more than 5 million deaths worldwide each year. Uncontrolled hemorrhage is the leading cause of preventable death in such cases, attributing about 50% of trauma-related deaths within 24 h of injury. Deaths from haemorrhage represents a substantial global problem, with more than 60,000 deaths per year in the United States and an estimated 1.9 million deaths per year worldwide, 1.5 million of which result from physical trauma. Therefore, we aim to look into the common pitfalls that both medical students and new physicians face in the recognition, diagnosis, and Emergency Traumatic Haemorrhagic Shock Resuscitations. Targeted population: Haemorrhagic Shock patients who are requiring urgent management in the ED, with Emergency Physicians for teaching approach protocol. Aim of the study: Appropriate for assessment and priorities for Haemorrhagic Shock Patients Resuscitations by training protocol to Emergency Physicians. Based on Resuscitations guidelines by applying the ATLS protocol in traumatic Haemorrhagic shock. Methods: Collection of all possible available data about the haemorrhagic patients' therapy in the Emergency department. By many research questions to achieve these aims so a midline literature search was performed with the keywords "critical care", "emergency medicine", "principals of urgent therapy in haemorrhage", "Resuscitations and ATLS". All studies introduced that the initial diagnosis of hypovolemia is a serious condition that face patients of the emergency and critical care departments. Literature search included an overview of recent definition, causes and recent therapeutic strategies. Conclusion: Haemorrhage is the cause of shock in most trauma patients and Treatment of these patients requires immediate haemorrhage control and fluid or blood replacement. Initial assessment of a shocked patient involves careful physical examination, finding signs of life-threatening problems and other causes of shock. In case of, Shock does not respond to initial crystalloid fluid bolus. Think about an internal bleeding or a non-Haemorrhagic source of shock. Keywords: Haemorrhagic shock, Emergency physicians; Skill approach; Management
... • Costochondritis: An inflammation of the cartilage between the ribs. Pain is typically located in the mid-chest, with intermittently dull and sharp pain that may be increased with deep breaths, movement, and deep touch [38]. ...
Introduction: The hospital ED is one of the most important components of the health care system. There is an increase in numbers of chest pain patients visiting EDs leading to overcrowding, long waiting time, missed diagnostic cases and negative impact on patient satisfaction. Chest pain is one of the most common reasons people call for emergency medical help. Fortunately, chest pain was not always a signal for a heart attack. Often chest pain is unrelated to any heart problem. However, even if the chest pain the patient experience has nothing to do with his cardiovascular system, the problem may still be important and worth the time spent in an emergency room for evaluation. So, we aimed to update knowledge and review researches in the field of chest pain and reduction in waiting time, missed diagnostic cases and Overcome Crowdness Patients in emergency department. Methods: Collection of all possible available data about the chest pain patients in the Emergency department. By many research questions to achieve these aims so, a midline literature search was performed with the keywords "critical care", "emergency medicine", "acute chest pain", "myocardial ischemia". All studies introduced that the myocardial ischemia is a serious pathology that face patients of the emergency and critical care departments. Literature search included an overview of recent definition, causes, pathophysiology, prophylactic and recent therapeutic strategies. Results: Myocardial Ischemia means narrowing of Coronaries whatever it was transient or permanent, partial or complete, painful or silent, recurrent or firstly experienced, recordable or not. This, although chambers are full of blood, makes heart muscle blood supply decreases and if it continued, it may result in myocardium permanent damage (Myocardial infarction). Conclusion: "Prevention is better than cure" Decline in death rates could be achieved by adopting a healthier lifestyle. That is why it is important for healthcare professionals to implement primary and secondary prevention. And there are many types emergency department of chest pain risk stratifications so any one of them should be applied e.g. TIMI or HEART score in daily emergency work. Keywords: Emergency Department; Myocardial Ischemia; Management
... In Egypt, it estimated that the mortality rate as result of cardiovascular diseases (5.6%) and by 2018, over millions people would suffer serious CA. Unfortunately, of all who suffer CA only less than 8% survive (3). ...
Aim: Determination of the effect of training CPR program on the nurses working practice and knowledge in Emergency department (ED). Nearly 20% survive rate in adult of hospital cardiac arrest (CA). Cardiopulmonary Resuscitation (CPR) is increase the survival rate into double number but CA without treatment is falling 10-15% per minute of survival rate; however, the performed proper CPR likely shifts this curve towards a higher probability of survival. Material and Methods: The study is Interventional included 65 nurses. They fill questionnaire sheet used and constructed via the Research Committee in Murcia's Hospital based on the "American Heart Association (AHA) 2010 Guidelines of CPR". To assess nurses' knowledge about sudden cardiac arrest and CPR but we used Pre and post questionnaire knowledge that applied in three phases: Assessment phase, Implementation phase, and Evaluation phase. Results:The study revealed 73% of nurses do not have previous training. Twenty-seven percentage nurses not have any information about CPR and 22.5% of them the main source of the information gained through training program more than one year ago. While the 94.6% of them willing to attend CPR training program and report they need to perform high quality CPR respectively. Conclusion: The study give a clear view of the current knowledge and practice of CPR among nursing staff in our institution and can help in developing it. It also gives detailed information about the exact weak points, which would improve, in next workshops.
... The major cause of unstability in polytrauma patients diagnosed by RUSH is hypovolemic shock (64%), followed by obstructive 13 , whose second and third causes are respectively cardiogenic shock and obstructive shock. Anyway hypovolemic shock is still the dominant cause. ...
- Adel Hamed Elbaih
- Ahmed M Housseini
- Mohamed E.M. Khalifa
Purpose "Polytrauma" patients are of a higher risk of complications and death than the summation of expected mortality and morbidity of their individual injuries. The ideal goal in trauma resuscitation care is to identify and treat all injuries. With clinical and technological advanced imaging available for diagnosis and treatment of traumatic patients, point of care---rapid ultrasound in shock and hypotension (RUSH) significantly affects modern trauma services and patient outcomes. This study aims to evaluate the accuracy of RUSH and patients outcomes by early detection of the causes of unstable polytrauma. Methods This cross-sectional, prospective study included 100 unstable polytrauma patients admitted in Suez Canal University Hospital. Clinical exam, RUSH and pan-computed tomography (pan-CT) were conducted. The result of CT was taken as the standard. Patients were managed according to the advanced trauma life support (ATLS) guidelines and treated of life threatening conditions if present. Patients were followed up for 28 days for a short outcome. Results The most diagnostic causes of unstability in polytrauma patients by RUSH are hypovolemic shock (64%), followed by obstructive shock (14%), distributive shock (12%) and cardiogenic shock (10%) respectively. RUSH had 94.2% sensitivity in the diagnosis of unstable polytrauma patients; the accuracy of RUSH in shock patients was 95.2%. Conclusion RUSH is accurate in the diagnosis of unstable polytrauma patients; and 4% of patients were diagnosed during follow-up after admission by RUSH and pan-CT.
- Eric Kagunza
A Case study of a 25 year old male motorcyclist (Alex) who was brought into the emergency department of Jaramogi Oginga Odinga Teaching and Referral Hospital by an ambulance following an accident. The patient vital signs were :blood pressure 80/42 mmhg, heart rate 130 b/m, minimal urinary output. Provide a detailed explanation of why Alex's blood pressure dropped, pulse increased and how his body system will respond to bring his blood pressure within normal range.
Background: IN 2010, Institute of Medicine in USA report that medical errors are estimated to result in about between 44,000 and 98,000 preventable deaths and 1,000,000 excess injuries each year in U.S. hospitals. The annual cost of treating medical injuries in USA has been estimated to be $9 billion. The objective of this study was to follow up guidelines in treatment of Traumatic hypovolemic shocked patients. Methods: The design of this study is a cross sectional descriptive study was conducted on traumatic patients who presented to the emergency department between the periods from October 2012 to October 2013. This study was conducted at the emergency department Suez Canal University Hospital, Ismailia, Egypt. On 100 patients with traumatic hypovolemic shock male or female within the age ranges from 18 years till 65 years old. Patients admitted to the hospital with other types of shock with trauma, non-traumatic hypovolemic shock, pregnant females, advanced malignancy, patients below 18 years old or patients more than 65 years old should excluded from the study. Questionnaire was filled by the researcher during resuscitation of the patient diagnosed as traumatic hypovolemic shock by the medical team in details; medical error was identified by comparing the actual management plan to the standard plan according to the guidelines from "The Washington manual of critical care". Results: This study was conducted on 100 patients who presented to the Emergency Department, Seuz Canal University Hospital, Ismailia, Egypt. Between the period from October 2012 to October 2013 in order to detect medical errors in treatment of Traumatic hypovolemic shocked patients and to reach the optimal scheme of management. 1-More than half of the patients were in age group (≥30-45). And most of them were males about 70% of the studied patients and females were 30%. 2- Most of the patients were delayed in hospital arrival as we found that 50% reached in more than 40 min. 3-The initial medical help in the pre-hospital period was given to almost all of the patients (94%). 4- Incomplete exposure of patients is a very frequent medical error occurs during hospital assessment in about 22% of patients. Conclusions: Failure in oxygen saturation monitoring and forgetting complete exposure of the patient has statistically significant relation with mortality during in hospital assessment of the patient. Delayed insertion of 2 large cannula or central line, Fluid given not warmed and blood received not at the proper time all of them show statistically significant Relation with mortality during in hospital resuscitation of the patient with traumatic hypovolemic shock. Keywords: Unwarmed fluids, Incomplete exposure, Temperature monitoring
- R Bellomo
- Marianne J Chapman
- S. Finfer
- D Williams
Background Low-dose dopamine is commonly administered to critically ill patients in the belief that it reduces the risk of renal failure by increasing renal blood flow. However, these effects have not been established in a large randomised controlled trial, and use of dopamine remains controversial. We have done a multicentre, randomised, double-blind, placebo-controlled study of low-dose dopamine in patients with at least two criteria for the systemic inflammatory response syndrome and clinical evidence of early renal dysfunction (oliguria or increase in serum creatinine concentration). Methods 328 patients admitted to 23 participating intensive-care units (ICUs) were randomly assigned a continuous intravenous infusion of tow-dose dopamine (2 mug kg(-1) min(-1)) or placebo administered through a central venous catheter while in the ICU. The primary endpoint was the peak serum creatinine concentration during the infusion. Analyses excluded four patients with major protocol violations. Findings The groups assigned dopamine (n=161) and placebo (n=163) were similar in terms of baseline characteristics, renal function, and duration of trial infusion. There was no difference between the dopamine and placebo groups in peak serum creatinine concentration during treatment (245 [SD 144] vs 249 [147] mu mol/L; p=0 . 93), in the increase from baseline to highest value during treatment (62 [107] vs 66 [108] mu mol/L; p=0 . 82), or in the numbers of patients whose serum creatinine concentration exceeded 300 mu mol/L (56 vs 56; p=0 . 92) or who required renal replacement therapy (35 vs 40; p=0 . 55). Durations of ICU stay (13 [14] vs 14 [15] days; p=0 . 67) and of hospital stay (29 [27] vs 33 [39] days; p=0 . 29) were also similar. There were 69 deaths in the dopamine group and 66 in the placebo group. Interpretation Administration of low-dose dopamine by continuous intravenous infusion to critically ill patients at risk of renal failure does not confer clinically significant protection from renal dysfunction.
- Joe Kanter
- Peter DeBlieux
To effectively treat an aging and increasingly complex patient population, emergency physicians and other acute-care providers must be comfortable with the use of vasopressors, inotropes, and chronotropes. These medicines are used to augment the cardiovascular function of critically ill patients. Each class of medication produces a different hemodynamic effect. Some agents produce only one of these actions, whereas others have multiple effects. For the emergency physician, these agents are used with the explicit goal of preserving vital organ perfusion during acute and severe illness. This article reviews the physiologic receptors targeted by such drugs, common agents used, and specific clinical indications for their use. Copyright © 2014 Elsevier Inc. All rights reserved.
Early diagnosis of haemorrhagic shock (HS) might be difficult because of compensatory mechanisms. Clinical scoring systems aimed at predicting transfusion needs might assist in early identification of patients with HS. The Shock Index (SI) – defined as heart rate divided by systolic BP – has been proposed as a simple tool to identify patients with HS. This systematic review discusses the SI's utility post-trauma in predicting critical bleeding (CB). We searched the databases MEDLINE, Embase, CINAHL, Cochrane Library, Scopus and PubMed from their commencement to 1 September 2013. Studies that described an association with SI and CB, defined as at least 4 units of packed red blood cells (pRBC) or whole blood within 24 h, were included. Of the 351 located articles identified by the initial search strategy, five met inclusion criteria. One study pertained to the pre-hospital setting, one to the military, two to the in-hospital setting, and one included analysis of both pre-hospital and in-hospital values. The majority of papers assessed predictive properties of the SI in ≥10 units pRBC in the first 24 h. The most frequently suggested optimal SI cut-off was ≥0.9. An association between higher SI and bleeding was demonstrated in all studies. The SI is a readily available tool and may be useful in predicting CB on arrival to hospital. The evaluation of improved utility of the SI by performing and recording at earlier time-points, including the pre-hospital phase, is indicated.
Source: https://www.researchgate.net/publication/317577007_Pathophysiology_and_management_of_different_types_of_shock
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