Transcript DEFINTION - Bradulskis

SHOCK
SHOCK DEFINTION
The common denominator in all forms of
shock is inadequate capillary perfusion.
Shock is Characterized by Inadequate
Tissue
Perfusion
and
Cellular
Hypofunction/Hypoxia.
Total body celular metabolism is malfunctional,
usually by inadequate delivery of oxyden to meet
celluar needs and occasionally of inability of cells
to utilize oxygene( methemoglobinemia, carbon
monooxide poisoning).
SHOCK
shock has been recognised for over 100
years, a clear definition is not estabilished
till this moment, the definition of shock
varies from time to time and has different
meanings according to the etiological and
pathogenetic factors, what caused it.
Classified by Etiology
by Mark A. Graber, MD:Departments of Family Medicine and Emergency
Medicine University of Iowa College of Medicine Peer Review Status:
Externally Peer Reviewed by Mosby
Hypovolemic shock from volume loss
(e.g., dehydration, blood loss, burns)
Distributive shock based on loss of
vascular tone (e.g., anaphylactic, septic,
bacteremic, toxic, neurogenic shock).
Classified by Etiology
by Mark A. Graber, MD:Departments of Family Medicine and Emergency
Medicine University of Iowa College of Medicine Peer Review Status:
Externally Peer Reviewed by Mosby
Cardiogenic shock based on pump
failure( acute myocardial infarction, ventricular
septal defect rupture, papillar muscles rupture,
ventricular aneurysm, severe aortic stenosis,
arrhythmias, trauma- tensione pneumothorax,
pericardial temponade, cardic contusion
Dissociative shock based on inability of
RBC to deliver oxygen
(e.g., methemoglobinemia, carbon monoxide posoning).
Most common clinical signs:

Hypotension. Blood pressure drop is
a late finding.
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An orthostatic systolic decrease of 10 to 20 mm
Hg or increase in pulse of 15 beats/min is
considered "significant."
Take orthostatic vital signs recumbent and after
standing for 1 to 2 minutes. * Orthostatic vital
signs may be normal in hypovolemic individuals,
or nor-mal individuals may exhibit orthostatic
changes; so use clinical judgment and base
treatment on symptoms. Alcohol ingestion, a
meal, increased age, antihypertensives, etc. may
cause orthostatic changes in BP and pulse in the
absence of hypovolemia.
Most common clinical signs:
Tachycardia usually present but
may not be, especially in the
presence of diaphragmatic
irritation, which causes vagal
stimulation, in neurogenic shock.
Most common clinical signs:
Hypoperfusion including decreased urine
output, decreased mentation, cool
extremities, mottling, etc.
* Goal of resuscitation is to maintain urine output
between 30 and 60 ml/hr.
Hypovolemic shock
Definition
It is present when marked reduction
in oxygen delivery results from
diminished cardiac output secondary
to inadequate volume of whole blood.
Hypovolemic shock
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The main causes are:
- external bleeding;
- internal bleeding;
- the loss of big amount of plasma due to wide
burns;
- the loss of liquids and electrolytes after long
lasting and hard diarrhea, vomiting;
- an internal loss of liquids due to pleuritis of
peritonitis, acute pancreatitis.
* three last sometimes nemed as oligemic shock
Hypovolemic shock
Pathophysiology:
diminishing cardiac output or fluid
flow secondary to decreasing venous
return
Hypovolemic shock
Clinicla signs:
hypotensia, tachycardia, tachypnoe,
oliguria, anxious, skin is pale and
cool, often patient have nausea and
vomiting, can be restless or comatose
Hypovolemic shock
acording American Surgeons Committee of Trauma 1988
Clinical signs
I class
II calss
III class
IV class
Blood loss
<750
750-1500
1500-2000
2000>
Blood loss%
<15
15-30
30-40
40>
Puls rate
<100
>100
>120
140>
AP
Normal
Normal
Decreased
Decreased
BR
14-20
20-30
30-40
>35
Urination(ml/h)
30>
20-30
5-15
<5
CNS function
A litttile anxious Middle anxious
Anxious or
suffocating
Suffocating or
lethargic
Hypovolemic shock
Laboratory determination:
arterial blood gases: pH is considered normal 7.35-7.45,
PaCO2 – 35-45mm/ml, in pH <7.35 is associated with a
normal or less normal PaCO2 -( metabolic acidosis)
 in vomiting by stenosis of pyloric part of ventriculus alcalosis
 serum electrolytes in hemorragic shock near normal, in
diarhhoe K↓, vomiting Na↓, pancreatitis Ca↓ ,K↓ and etc.
 creatinine is usefule as an indicator of renal function
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Hypovolemic shock
Treatment and menagemant of hypovolemic
shock principles:
monitoring of blood pressure, urination, breafing
function, HR
 replasment of blood volume ( Ringer lactate,
solutions similar to plasma in electrolites
composition, starch or gelatin solution, in
bleading erythrocite mass
 supplemental oxygene
 after resuscitation surgery manipulations,
interventionaly radiology, endoscopy, drugs.

Distributive shock
septic, bacteremic shock - based on
loss of vascular tone, bacteremia and
septic shock are closely related
conditions.
Distributive shock
Bacteremic shock develops when hight
amount of of bacteremia or fungs and its
toxic agents penetrate into the blood and
when the host defenses are decreased
due to prolonged and hard infectional
illness.
Distributive shock
Septic shock is sepsis with
hypoperfusion and hypotension refractory
to fluid therapy.
 When bacteremia produces changes in
circulation such that tissue perfusion is
critically reduced, septic shock ensues.
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Distributive shock
The main causes are:
Septic shock is more often caused by hospitalacquired gram-negative bacilli and usually
occurs in immunocompromised patients and
those with chronic diseases.
 In about 1/3 of patients it is caused by grampositive cocci and by Candida organisms.
 Shock caused by staphylococcal toxins is called
toxic shock, a condition more frequently
occurring in young women.
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Distributive shock
Predisposing factors: diabetes mellitus, cirrhosis,
leukopenic states, especially those associated
with underlying neoplasms or treatment with
cytotoxic agents,
 antecedent infection in the urinary, biliary or GI
tracts,
 invasive devices- catheters, drainage tubes, and
other foreign materials and prior treatment with
antibiotics, corticosteroids, or ventilator devices.
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Distributive shock
Septic shock occurs more often in
newborns, patients > 35 yr, pregnant
women, and those seriously
immunocompromised by underlying
diseases or iatrogenic complications of
treatment.
Distributive shock
Pathogenesis
The bacterial toxins generated by the infecting
organisms trigger complex immunologic
reactions: a large number of mediators,
including TNF, leukotrienes, lipoxygenase,
histamine, bradykinin, serotonin, and IL-2, have
been implicated in addition to endotoxin (the
lipid fraction of the lipopolysaccharides released
from the cell wall of gram-negative enteric
bacilli).
Distributive shock
Warm shock: initially, vasodilatation of
arteries and arterioles occurs, decreasing
peripheral arterial resistance with normal
or increased cardiac output even though
the ejection fraction may be decreased
when heart rate increases.
Distributive shock
Cold shock: later, cardiac output may decrease
and peripheral resistance may increase. Despite
increased cardiac output, blood flow to the
capillary exchange vessels is impaired, and the
delivery of vital substrates, especially O2, and
the removal of CO2 and waste products are
decreased. This decreased organ perfusion
particularly affects the kidneys and brain, and
subsequently causes failure of one or more of
the visceral organs. Ultimately, cardiac output
declines and the typical features of shock
appear.
Distributive shock
Clinical signs:
 altered mental alertness, chacking chill, rapid
rise of body temperature, BP decreased to <
80mm Hg , the skin is warm (paradoxically warm
extremities), tachycardia, tachyon, and oliguria;
 late cool, pale extremities with peripheral
cyanosis and mottling are late signs, with
progression, multiorgan failure involves the
kidney, lungs, and liver; disseminated
intravascular coagulation (DIC) and heart failure
may also occur.
Distributive shock
Laboratory determination:
leucocytosis, with marcet shift to left,
associated with a sharp decrease in
platelet count to <= 50,000/µL,
respiratory alcalosis, metabolic acidosis,
toxic anemia, positive blood cultures.
Distributive shock - Managment
should be treated in an ICU, the following
should be monitored frequently: systemic
pressure, arterial and venous blood pH, arterial
blood gas levels, blood lactate level, renal
function, electrolyte levels, and possibly tissue
PCO2, urine output should be measured, usually
with an indwelling catheter, as an indication of
splanchnic blood flow and visceral perfusion,
Distributive shock - Managment
the CVP or pulmonary artery pressure
should be measured, and fluid
replacement should be given until the CVP
reaches 10 to 12 cm H2O or until the
pulmonary wedge pressure reaches 12 to
15 mm Hg,
Distributive shock - Managment
respiration should be supported with nasal
O2, tracheal intubation or tracheostomy,
and mechanical ventilation as necessary,
Distributive shock - Managment
parenteral antibiotics should be given after
specimens of blood, body fluids, and wound
sites have been taken for Gram stain and
culture;
 prompt empiric therapy is essential, the choice
of an antibiotic requires an educated guess
based on the results of previous cultures from
the site of the primary infection or on the clinical
setting in which the primary infection occurred.
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Rare cases of shock
Shock due to the hormonal
insufficiency – gl thyroydea,
hipofhysis and etc. (type distributive
shock);
Rare cases of shock
Neurogenic shock – hypotension secondary to
central nervous system dysfunction, it is result of
dysruption of the sympathetic nervous system
(type is distributive shock).
 The main causes are: trauma or lumbal anesthesia due to vasomotoric disfunction –
paralysis. It results in vaso-dilatation and
decresed vascular resistence -> blood
insufficiency in a circulatory system.
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Rare cases of shock
Neurogenic shock
The main causes are: trauma or
lumbal ane-sthesia due to
vasomotoric disfunction – paralysis. It
results in vaso-dilatation and
decresed vascular resistence -> blood
insufficiency in a circulatory system.
Rare cases of shock
Shock due to the hyperergic reactions allergic reactions develope if the patients
is hypersensitive to various antigenes
(type distributive shock).