Shock

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Diagnosis and Management of
Shock
Dr. Anas Khan
Consultant, EM
MBBS, MHA, ArBEM
428 C2 notes
Objectives
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Identify the 4 main categories of shock.
Discuss the goals of resuscitation in shock.
Summarize the general principles of shock
management.
Describe the physiologic effects of
vasopressors and inotropic agents.
CASE STUDY
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A 25 Years old lady, with no prior history of
any chronic disease, presented to the
emergency department C/O productive
cough of greenish yellow sputum.
V/S
Temp: 38.8 ( each 1o C higher in
temperature must have an increase in
HR by 10-15 beats, here after
calculations HR is still higher then it
should be (115).
 HR:
129 /Min (60-100/min)
 R.R:
27 /Min ( 16-20/min)
 BP:
112/68
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Questions
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Where do you triage this Pt.?
Triage : to prioritize the patients
Information we still have to collect to be able to classify the
patient : condition of patient , if in distress, check vitals
BP,HR,RR,temperature,oxygen saturation,glucocheck if the
patient is dizzy
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What information do you need to determine if this Pt. is in
shock?
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What initial interventions are needed to stabilize that Pt.?
Shock
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Shock is a syndrome of impaired tissue oxygenation and
perfusion due to a variety of etiologies that will result in different
manifestations according to organ affected.
Liver --- nausea/vomiting
Heart --- tachycardia
Lung --- SOB
Brain --- confusion
kidney --- oliguria and late stage anuria
If left untreated
- Irreversible injury
- Organ dysfunction
- Death
Clinical Alterations in Shock
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The presentation of patients with shock may
be subtle (mild confusion, tachycardia).
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Or easily identifiable (profound hypotension,
anuria)
Pathophysiology:
1- Inadequate tissue perfusion and
oxygenation
2- Compensatory responses
3- The specific etiology --- you should
manage the patient but must aim to
treat the underlying cause.
Classification
1- Hypovolemic: (hemorrhagic (internal as bleeding ulcers or external as acute
blood loss), non-hemorrhagic ( dehydration as vomiting and diarrhea,3rd fluid
spacing as in burns and pancreatitis).
2- Cardiogenic: pump related, any type of cardiomyopathies (ischemic,
myopathy, mechanical,
arrhythmogenic either braycardic or tachycardia).
3- Distributive: mainly due to vasodilation (septic, adrenal crises due to
steroids withdrawal mostly iatrogenic, neurogenic loss of sympathetic tone
when there is trauma to the thoracic or lumbar sympathetic chain or spinal cord
injury,
anaphylactic as in
hypersensitivity reactions if severe form).
4- Obstructive: (massive PE, tension pneumothorax(space is obstructed by
fluid),
cardiac tamponade( space is obstructed with blood,
constrictive pericarditis(space is obstructed due to the inflammation.)
*spinal shock is different from neurogenic , its just motor loss which is transient and
due to concussion, no vascular changes so not considered as an ER shock
X-ray of tension pneumothorax
which is an immediate ER.
CT of pulmonary embolism
Hypovolemic Shock
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When the IV volume is depleted relative to
the vascular capacity as a result of:
1- Hemorrhage.
2- GI loss
3- Urinary loss
4- Dehydration
Hypovolemic Shock
Management
- The goal is to restore the fluid lost
- Vasopressors are used only as a temporary
method to restore B.P until fluid resuscitation
take place
* Mainly we give good volume of fluids to
prevent heart failure . Vasopressors has no
role .
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Distributive shock
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It is characterized by loss of vascular tone.
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The most common form of distributive shock
is septic shock.
Hemodynamic Profile
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Cardiac output
normal or increased
Ventricular filing pressure normal or low
SVR
low
Diastolic pressure low
Pulse pressure
wide
Management of Septic Shock
The initial approach to the patient with septic shock is the
restoration and maintenance of adequate intravascular volume.
* If not maintained by fluids we give vasopressors unlike
hypovolemic shock .
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Prompt institution of appropriate antibiotic.
* In each 1 hour delay in antibiotics initiation will increase 6.7%
mortality .
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Cardiogenic Shock
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Forward flow of blood is inadequate because
of pump failure due to loss of functional
myocardium.
It is the most severe form of heart failure and
it is distinguished from chronic heart failure
by the presence of:
- hypotension, hypo perfusion and the need
for different therapeutic interventions.
Hemodynamic Profile:
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Cardiac output
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Ventricular filing pressure * Venous return
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SVR *systemic vascular resistance
Mixed venous O2 sat
Low
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Low
High
High
Management of Cardiogenic Shock
The main goal is to improve myocardial
function.
 Arrhythmia should be treated.
 Reperfusion PCI is the treatment of choice in
ACS.
* Percutaneous Coronary Intervention standard
of care , should be started within 90 minutes
window if not then go for thrombolytic agents .
 Inotropes and vasopressors.
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Obstructive Shock
Obstruction to the outflow due to impaired
cardiac filling and excessive after-load
 Cardiac tamponade & constrictive pericarditis
impair diastolic filling of the Rt. ventricle
 Tension pneumothorax obstructs venous
return limiting Rt. ventricular filing.
* In tension pneumothorax there is positive
gradient pressure limiting venous return
 Massive pulmonary embolism increase the
Rt. ventricular after-load.
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Hemodynamic Profile
Cardiac output
low
 Afterload * same as SVR (systemic venous
return )
high
 Lt.Vent.filling pressure variable
 Pulsus paradoxicus
(in Tamponade)
* Pulsus paradoxicus normally with inspiration it
increase by 10 beats if more then positive for
temponade .
 Distended Jugular veins
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Management Of Obstructive Shock
Directed Mainly to Management of the cause.
General Principles
The overall goal of shock management is to improve oxygen
delivery or utilization in order to prevent cellular and organ
injury.
* Defect in utilization as in CO poising because hemoglobin has
higher affinity to CO and even if one oxygen went there the CO will
prevent the off-load and if it did at the mitochondrial level it wil
block the respiratory chain .
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Effective therapy requires treatment of the underlying etiology.
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Restoration of adequate perfusion, monitoring and
comprehensive supportive care.
Interventions to restore perfusion center on achieving an
adequate BP, increasing cardiac output and optimizing oxygen
content of the blood (goal directed therapy).
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Oxygen demand should also be reduced.
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* Most important is 1- Brain , 2- Heart and
3- Diaphragm which take 30% of oxygen found in blood ,
mechanical ventilation in all this you should decrease demand .
* Hyperdynamic state : Thryrotoxicosis , Anemia , Fever and late
term pregnancy .
In Summery, Shock Management:
1- Monitoring.
2- Fluid Therapy.
3- Vasoactive agents.
4- Treat the underlying cause.
THANK YOU
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