Shock Flashcards
Criteria to diagnose as shock
- Hypotension
- Tachycardia (often first symptom)
- Oliguria
- AMS (altered mental status may be only presenting symptom
- Peripheral hypoperfusion and impaired O2 delivery* MOST IMPORTANT
Basic progression of shock
- Arterial blood flow can not keep up with demand of tissues metabolic needs
- Resulting in hypoxia to the body as a whole
- Resulting in anaerobic metabolism to kick in at peripheral tissues
- *Resulting in lactic acidosis (lactic acid build up, very bad)**
Overall: Decreased oxygen to peripheral tissues
4 types of shock
Hypovolemic
Cardiogenic
Obstructive
Distributive
Hypovolemic shock
- Decreased intravascular volume
- Due to loss of blood or fluid and electrolytes
- Blood loss from whatever reason (trauma, ruptured ectopic pregnancy, GI bleed, etc)
- Loss of fluid and electrolytes (N/V/D)
- Body will compensate by vasoconstricting, but after 15% loss of volume, shock sets in.
- Anything that decreases BP can cause shock; body responds by vasoconstriction
S/S of Hypovolemic shock
- Oliguria, AMS, cool extremities, diaphoresis, pale
- Narrow pulse pressure (reduced stroke volume)
- DECREASED PCWP, CO, & venous return; Elevated TPR (HIGH output failure)
- Improves with fluids
Cardiogenic shock
- From cardiac failure
- Heart can not maintain necessary cardiac output
- Definition: as evidence of tissue hypoxia due to decreased cardiac output in the presence of adequate intravascular volume
- Could be from MI, cardiomyopathy, valve dysfunction, arrhythmias
S/S of Cariogenic shock
- Oliguria, mental status changes, diaphoresis, cool extremities, jugular venous pressure is elevated, pulmonary edema might be present with respiratory failure.
- LOW output failure (elev TPR, Low CO & venous return)
- ELEVATED PCWP (pulmonary wedge pressure)
- Blood pressure improves with fluids
How to differ between cardiogenic and hypovolemic shock
Cardiac echocardiogram
Hypovolemic shock: LV will be small due to poor filling, but maintains contractility (not enough fluid to pump); but contractility is fine
Cardiogenic shock: decrease in LV contractility (THIS IS THE DIFFERENCE; problem with your heart, contractility on echo will be different)
Obstructive shock
- Cardiac tamponade
- Tension pneumothorax (needle first remember, not chest tube)
- Massive PE
Distributive shock (septic, SIRS, neurogenic, anaphylaxis)
- AKA vasodilatory shock
- Produces a decreases in systemic vascular resistance; resulting tissue hypoperfusion
S/S of Distributive shock (septic, SIRS, neurogenic, anaphylaxis)
- Normal circulatory volume
- Low TPR, PCWP
- Elevated CO, venous return (HIGH output failure)
- Vasodilation (warm dry skin)
SIRS
- type of distributive shock
- Systemic Inflammatory Response Syndrome
- Can occur from an infectious cause, or noninfectious (burns, pancreatitis, trauma, ischemia)
Criteria for SIRS
TEST!
Need to have at least two of the following:
- Temp >100.4, or 90
- RR >20 or hyperventilation with a CO2 on abg 12 or 10% bands
Septic shock
- SIRS + a source (uti, pneumonia, cellultis, meningitis)
- Most common type of distributive shock
- 20-50% mortality
- Risks are age, DM, immunosupression, recent invasive procedures
Shock in setting of DIC from trauma often is from sepsis
Most common agents that cause septic shock
gram negatives (E coli, Pseudomonas, Klebsiella)
Neurogenic shock
- type of distributive shock
- Caused by traumatic spinal cord injury or by effects of an epidural, or spinal anesthetic
- Loss of sympathetic tone and systemic vascular resistance
- Hypotension WITHOUT a compensatory tachycardia
- A benign other type of neurogenic shock which can result in syncope is “vasovagal syncope”—caused by pain, gastric dilatation, or fright, producing hypotension, bradycardia, and syncope
S/S of shock in general
- everything vasoconstricts (brain is last to be effected)
- Hypotension (this may be masked in early stages by compensatory mechanisms such as tachycardia, increased cardiac contractility, and vasoconstriction)
- Cool and mottled extremities (red blotches, usually starts in legs, bad sign)
- Splanchnic vasoconstriction can lead to oliguria (decreased urine output), bowel ischemia, hepatic dysfunction, MSOF (Multi system organ failure- all of the above put together)
- Altered mental status (AMS is very very common)
Sepsis markers in blood
Lactate (very bad)
Procalcitonin
General treatment
- ABC’s with prompt intervention
- Respiratory failure not uncommon—due to existing metabolic acidosis. Intubation can reduce O2 demand of respiratory muscles and allow improved oxygen delivery to other hypoperfused tissues.
- Will develop compensatory respiratory alkalosis (will need to be intubated)
- Monitor urinary output, possibly foley (may have renal failure)
- IVF for hypotension
What to give first? Blood or saline?
Give blood before giving saline, need to increased oxygen carrying capacity, giving BLOOD is more important, can give O- blood immediately (don’t need to waste time typing)
-If you give them fluids when they are in shock, can make it worse (inducing CHF; try giving very small boluses)
For Septic shock, the standard is to give
GET 30 cc/kg (of weight) of fluid without exception, given all at once
This is a standard- main goal is to reverse hypotension
Early Goal Directed Therapy for Septic Shock
Will be a patient case on this on the TEST*
- .9NS (saline) to achieve CVP 8-12 mm Hg
- Vasopressors to achieve MAP 65 mm Hg or greater
- PRBCs (packed red blood cells) to achieve Hgb of 10 or greater
- Results in lower mortality and morbidity*
When to give Pressors
- When fluids don’t work to maintain blood pressure
- Need central line to give (central lines go in VEINS)
- Dobutamine, Norepinephrine (Levophed), vasopressin, dopamine
Can’t give Pressors through IV in arm because
it increases the pressure in that area, necrosis will happen in that area, can lose limb (VERY BAD, this can happen if you accidentally put central line in artery)
- central lines MUST go in veins
- To see if central line is in artery or vein- draw blood gas from central line, and draw a gas from a known artery, if they are the same- BAD (line is accidentally in artery, ABGs should be VERY different from artery and vein)
When to use Corticosteroids
- Used when shock is due to adrenal insufficiency
- Otherwise, most articles do not show its routine use in shock beneficial
-Goal is to stop inflammation, but only works when problem is adrenal insufficiency
Antibiotics are used for
Septic shock and SIRS
Nursing home pts- treat for MRSA Treat with Vancomycin
