Shock Flashcards
What is shock?
Inadequate tissue perfusion
What are the 5 different types of shock?
- Hypovolemic
- Septic
- Cardiogenic
- Neurogenic
- Anaphylactic
What are the signs of shock?
Pale, diaphoretic, cool skin, hypotension, tachycardia, tachypnea, decreased mental status, decreased pulse pressure, poor capillary refill, poor urine output
What are the best indicators of tissue perfusion?
Lactic acid (elevated with inadequate tissue perfusion), base deficit, pH from ABG (acidosis associated with inadequate tissue perfusion)
What is hypovolemic shock?
Decreased intravascular volume
What are the common causes of hypovolemic shock?
Hemorrhage, burns, bowel obstruction, crush injury, pancreatitis
What are the signs of hypovolemic shock?
Early: Orthostatic hypotension, mild tachycardia, anxiety, diaphoresis, vasoconstriction (decreased pulse pressure with increased diastolic pressure).
Late: Changed mental status, decreased BP, marked tachycardia.
What are the signs and symptoms of class I hemorrhage (< 15% or 750 cc blood loss)?
Mild anxiety, normal vital signs
What are the signs and symptoms of class II hemorrhage (15-30% or 750-1500 cc blood loss)?
Normal systolic BP with decreased pulse pressure, tachycardia, tachypnea, anxiety
What are the signs and symptoms of class III hemorrhage (30-40% or 1500-2000 cc blood loss)?
Tachycardia (HR > 120), tachypnea (RR > 30), decreased systolic BP, decreased pulse pressure, confusion
What are the signs and symptoms of class IV hemorrhage (> 40% or 2000 cc blood loss)?
Decreased systolic BP, tachycardia (HR > 140), tachypnea (RR > 35), decreased pulse pressure, confused and lethargic, no urine output
What is the treatment for hypovolemic shock?
- Stop the bleeding
2. Volume (IVF like LR then blood products as needed)
What is a bedside indicator for treatment of hypovolemic shock?
Urine output, BP, HR, mental status, extremity warmth, capillary refill, body temperature
What labs can be used to determine the effectiveness of the treatment of hypovolemic shock?
pH, base deficit, and lactate level
What usually causes failure of resuscitation from hypovolemic shock?
Persistent massive hemorrhage, requiring emergent surgical procedure
Why does decreased pulse pressure occur with early hypovolemic shock?
Pulse pressure (systolic - diastolic BP) decreases because of vasoconstriction, resulting in an elevated diastolic BP
What is the most common vital sign change associated with early hypovolemic shock?
Tachycardia
What type of patient does not mount a normal tachycardic response to hypovolemic shock?
Patients on beta-blockers, spinal shock (loss of sympathetic tone), endurance athletes
Should vasopressors be used to treat hypovolemic shock?
No
Should patients with hypovolemic shock be put into Trendelenburg position?
No
What is septic shock?
Documented infection and hypotension
What is the specific etiology of septic shock?
Most common: gram-negative septicemia
Less common: gram-positive septicemia, fungus
What factors increase the susceptibility to septic shock?
Any mechanism that increases susceptibility to infection (e.g. trauma, immunosuppression corticosteroids, hematologic disease, diabetes)
What complications are major risks in septic shock?
Multiple organ failure, DIC, death
What are the signs and symptoms of septic shock?
Initial: Vasodilation (warm skin and full pulses), normal urine output.
Delayed: Vasoconstriction, poor urine output, mental status changes, hypotension.
What percentage of blood cultures is positive in patients with bacterial septic shock?
50%
What are the associated findings with septic shock?
Fever, hyperventilation, tachycardia
What are the associated lab findings with septic shock?
Early: Hyperglycemia, glycosuria, respiratory alkalosis, hemoconcentration, leukopenia.
Late: Leukocytosis, acidosis, elevated lactic acid.
What is the treatment for septic shock?
- Volume (IVF)
- Antibiotics (empiric, then by cultures)
- Drainage of infection
- Pressors PRN
- Zygris PRN
What is Zygris?
Activated protein C, shown to decrease mortality in septic shock and multiple organ failure
What is cardiogenic shock?
Cardiac insufficiency.
Left ventricular failure (usually), resulting in inadequate tissue perfusion.
What are the causes of cardiogenic shock?
MI, papillary muscle dysfunction, massive cardiac contusion, cardiac tamponade, tension PTX, cardiac valve failure
What are the signs and symptoms of cardiogenic shock?
Dyspnea, rales, pulsus alternans (increased pulse with greater filling following a weak pulse), loud pulmonic component of S2, gallop rhythm, hypotension, decreased cardiac output, elevated CVP/wedge pressure, decreased urine output, tachycardia (possibly)
What are the signs of cardiogenic shock on CXR?
Pulmonary edema
What is the treatment for cardiogenic shock?
- CHF: Diuretics and afterload reduction (e.g. ACE inhibitors +/- pressors).
- Left ventricular failure (MI): pressors, afterload reduction.
What are the last resort support mechanisms for cardiogenic shock?
IABP, VAD
What is neurogenic shock?
Inadequate tissue perfusion from loss of sympathetic vasoconstrictive tone
What are the common causes of neurogenic shock?
Complete transection of spinal cord, partial cord injury with spinal shock, spinal anesthesia
What are the signs and symptoms of neurogenic shock?
Hypotension, bradycardia, neurologic deficit
Why are HR and BP decreased in neurogenic shock?
Loss of sympathetic tone (but hypovolemia must be ruled out)
What are the associated findings with neurogenic shock?
Neurologic deficits suggesting cord injury
What must be ruled out in any patient where spinal shock is suspected?
Hemorrhagic shock
What is the treatment for neurogenic shock?
IVF (vasopressors reserved for hypotension refractory to fluid resuscitation)
What percentage of patients with hypotension and spinal neurologic deficits have hypotension of purely neurogenic origin?
67%
What is spinal shock?
Complete flaccid paralysis immediately following spinal cord injury.
May or may not be associated with circulatory shock.
What is the lowest reflex available to the examiner?
Bulbocavernous reflex (checking for contraction of the anal sphincter upon compression of the glans penis or clitoris)
What is the lowest level voluntary muscle?
External anal sphincter
What are the classic findings associated with spinal cord shock?
Hypotension, bradycardia (or lack of compensatory tachycardia)
What is the acronym for treatment options for anaphylactic shock?
BASE:
Benadryl, Aminophylline, Steroids, Epinephrine
