Cardiology #9 (Shock) Flashcards
The physical responses to shock are mediated by 6 things. Name them.
Antidiuretic hormone (ADH) Renin Catecholamines Glucagon Growth Hormone Cortisol
What exactly is shock?
Inadequate organ perfusion and tissue oxygenation to meet the body’s needs. Based on either low cardiac output or high systemic vascular resistance
The first type of shock, hypovolemic shock is _____ and occurs due to _____
Loss of blood or fluid volume due to hemorrhage or fluid loss
Common causes of hypovolemic shock
- Hemorrhagic: GI bleed, AAA rupture, massive hemoptysis, ectopic pregnancy
- Non-blood fluid loss: Vomiting, bowel obstruction, pancreatitis, severe burns, DKA
What is the pathophysiology of hypovolemic shock?
Loss of blood fluid volume –> increases HR –> vasoconstriction, hypotension, low cardiac output
-The body’s response is peripheral vasoconstriction, increase cardiac activity, Na/water retention, and increase cortisol
Symptoms of hypovolemic shock
Tachycardia Hypotension Oliguria or Anuria Pale cool dry skin Slow capillary refill > 2 seconds Decreased skin turgor Dry mucous membranes AMS
EVERYTHING IS DRY AND SLOW
What are the hallmark symptoms that diagnose a patient with hypovolemic shock?
Vasoconstriction (increased SVR)
Hypotension
Decreased cardiac output and pulmonary capillary pressure
Treatment of hypovolemic shock
ABCDEs, insert 2 large bore IV lines or central line
Volume resuscitation: crystalloid (Normal Saline or Lactated Ringers) 3-4 liters
Monitor urine output to assess further need for fluid
Packed RBC blood transfusion if severe hemorrhage
Prevention of hypothermia
What are the ABCDE’s of shock management
A: Airway (intubation)
B: Breathing (mechanical ventilation and sedation)
C: Circulation (Normal Saline, Lactated Ringer’s)
D: Delivery of Oxygen (monitor lactate levels)
E: Endpoint of Resuscitation (urine output 0.5ml/kg/hr, CVP 8-12 mmHg, MAP 65-90 mmHg)
Cardiogenic shock often produces what symptom that hypovolemic shock does not?
Increased respiratory effort/distress
Etiology of cardiogenic shock
Cardiac disease: MI, myocarditis, cardiomyopathy, congenital heart disease, arrhythmias
What is one unique thing about the treatment for cardiogenic shock?
Isotonic fluids are given in small amounts. The only type of shock in which LARGE amounts of fluid are not given.
What are the other treatment recommendations for cardiogenic shock?
- Inotropic support: drugs to increase cardiac output such as Dobutamine, Epinephrine, Amrinone
- Treat the underlying cause: If MI, early angioplasty or thrombolytics
What is obstructive shock?
Obstruction of blood flow due to physical obstruction of heart of great vessels
What are 4 HUGE etiologies of obstructive shock?
- Massive pulmonary embolism: obstructed pulmonary artery blood flow.
- Pericardial Tamponade: blood in pericardial space prevents venous return to heart
- Tension pneumothorax: positive air pressure causes external pressure on heart
- Aortic dissection
What is distributive shock?
Excess vasodilation and altered distribution of blood flow with shunting of blood flow from vital organs (heart, kidney) to non-vital tissues (skin, skeletal muscle)
What are the three factors of distributive shock?
- Decreased CO
- Decreased Systemic vascular resistance
- Decreased pulmonary capillary wedge pressure
MC type of distributive shock?
Septic Shock
Pathophysiology of septic shock
-infective organisms active the immune system –> host produces systemic inflammatory response –> cytokines cause peripheral vasodilation –> lowers SVR, and increases capillary permeability which induces shock and end organ thrombosis
Symptoms of septic shock
- Hypotension with wide pulse pressure (bounding peripheral arterial pulses)
- Only major type of shock with increased cardiac output (fast capillary refill time, warm, flushed extremities)
- Fever or hypothermia (<96.8)
- Pulse > 90
- RR > 20
- WBC > 12,000 or < 4,000
Management of septic shock
- Broad spectrum IV ABX: Zosyn + Ceftriaxone or Imipenem
- IV Fluid Resuscitation: isotonic crystalloids (Normal saline, Lactated Ringer’s)
- Vasopressors: if no response to 2-3 L of fluids.
1st line treatment for anaphylactic shock
Epinephrine (0.3mg IM) Airway management Antihistamines IVF Observe patients for 4-6 hours
Why should you observe patients for 4-6 hours after anaphylactic shock?
Up to 20% of patients have a biphasic phenomenon (return of symptoms 3-4 hours after the initial reaction)
What is neurogenic shock?
due to acute spinal cord injury
Symptoms of neurogenic shock
- Wide pulse pressure
- Bradycardia
- Hypotension
- Warm, dry skin
- Loss of sympathetic tone
Endocrine shock (such as Addisonian crisis) has a first line management of
Hydrocortisone 100mg IV
