Shock - Abrams Flashcards
What do we NOT do if someone goes into shock?
Put their feet up
What is shock?
- Hypoperfusion of vital organs (brain, heart, kidney, lungs, gut)
- It is NOT low bp, can be hypertensive or normal bp
Are you in shock if you are alert and sharp?
NO
What does lack of oxygen in shock lead to?
Anaerobic metabolism
- Lactic acid production is a marker of severity of oxygen supply/demand imbalance.
- By following the lactic acid you can track the course of the illness/treatment effectiveness
What don’t you need for shock?
CORTISOL!
What are the typical signs of shock that result form loss of cellular integrity?
- Hyperkalemia (high K+)
- Hyponatremia (low Na+)
- Metabolic acidosis (too much H+)
- Hyperglycemia (excess glucose)
- Lactic acidosis
What is systemic tissue perfusion a balancing act between?
Cardiac Output and Systemic Vascular resistance
What is the continuum of shock?
Shock is a broad term which encompasses a progression from SIRS (systemic inflammatory response syndrome) to MODS (multi-organ dysfunction syndrome)
What is SIRS?
Systemic inflammatory response syndrome
What is MODS?
Multi-organ dysfunction syndrome
What happens when MODS starts?
This is when the dec. organ perfusion begins
What is required for SIRS?
Atleast two of:
- Temp (less than 36C, higher than 38C)
- Pulse (tachycardic)
- Respirations (>20 - tachypnea)
- PaCO2 (12,000 or 10% bands
What can you think of SIRS as?
Septic like disorder in the absence of infection!!
Either sepsis or SIRS can progress to…
MODS (multi-organ dysfunction syndrome)
What are the classical findings in shock?
-Hypotension (systolic
How should you monitor a patient with shock?
-Level of alternates
-Urine output
(also lactic acid, CXR, bp, O2 saturation, Hgb (Hct))
What is the Shock Index (SI)?
- Heart rate divided by systolic pressure
- The index is inversely related to effective left ventricular stroke work
- A normal index = 0.5-0.7
- Index at or above 1 has increased mortality
- An elevated IS is more useful than a normal one to extrapolate morbidity/mortality
What is the capillary wedge pressure?
- Swan Ganz catheter reflects the left ventricular pressure but the use of these catheters has been associated with INCREASED MORTALITY
- DON’T USE ANYMORE!!
What are the four major categories of shock>
- Cardiogenic (heart fails)
- Hypovolemic (lack of fluid)
- Extracardiac (outflow obstruction)
- Dissociative (increased area for blood to disperse to) - outlier
What happens in cariogenic shock?
-Causes decreased CO due to pathology of heart
What pathologies are associated with cariogenic shock?
- Acute MI (>40% myocardial damage)
- Arrhythmia (too fast or slow)
- Out-flow obstruction
- -AS (Aortic Stenosis)
- -Hypertrophic cardiomyopathy (used to be called IHSS)
- Mitral regurgitation, VSD (ventricular septal defect)
What happens in Distributive/Dissociative Shock?
- Initially CO is increased, then it falls.
- Dec. Systemic Vascular Resistance or maldistribution
What pathologies are associated with distributive/dissociative shock?
- Septic shock
- -Gram - bacteria release endotoxins
- -Gram + bacteria release exotoxins
- Spinal cord injury
- Anaphylaxis
- Cyanide
- Carbon monoxide
What happens in Extracardiac shock?
Outflow obstruction!!
-Causes decreased cardiac output due to external pathology
What pathology is associated with extra cardiac shock?
- Pulmonary emboli
- Pericardial tamponade (fluid bulid-up around the heart within the pericardium)
- Constrictive pericarditis
- Pulmonary hypertension
- Cor pulmonale
What happens in hypovolemic shock?
Lack of fluid!!
-Causes decreased CO due to decreased preload
What pathologies are associated with hypovolemic shock?
- Diarrhea, vomiting, diuretics, sweating
- Hemorrhage
- Burns
- 3rd spacing: ascites (fluid collection in abdomen)
What is the PRIMARY principle of shock treatment?
Volume replacement!! (Normal saline (20-30 ml/kg), blood)
What agents can you use for shock?
Vasopressor agents! (inc. vasoconstriction and inc. MAP)
(NE, EPI, DA, dobutamine)
-No difference in efficacy or safety of first two!!
Do you use hypothermia in post cardiac arrest patients?
not usually
What else can you use to treat shock?
Antibiotics, surgery, thrombolytics, anticoagulants
What about insulin?
Evidence is mixed at best for use of insulin in shock or the routine use of adrenal replacement steroids.
