Shock

Question 1

What is the presentation of undifferentiated shock?

Answer 1

• tachycardia
• hypotension
• lactic acidosis
• anuria/oliguria
• altered mental status

Question 2

What does shock effect in the body?

Answer 2

• cardiac output
• SVR
• volume status = JVP or pulmonary capillary wedge pressure (PCWP)

Question 3

What are the hemodynamic parameters of hypovolemic shock?

Answer 3

CO -> decrease
preload (PCWP) -> decreased
after load (SVR) -> increased
O2 -> decreased

• due to fluid loss of hemorrhage

Question 4

What are the hemodynamic parameters of cardiogenic shock?

Answer 4

CO -> decreased
preload (PCWP) -> increased
after load (SVR) -> increased
O2 -> decreased

• due to cardiac ischemia, arrhythmias, valvulopathy, cardiotoxic substance exposure

Question 5

What are the hemodynamic parameters of distributive shocks?

Answer 5

CO -> increased
Preload (PCWP) -> decreased or normal
After load (SVR) -> decreased
O2 -> increased

• due to septic shock, anaphylactic shock, & neurogenic shock

Question 6

How should u approach a case of undifferentiated shock?

Answer 6

1- ABCs
2- determine the cause by history & examination
3- Two large-bore IVs if fluid resuscitation is indicated -> fluid bolus (NOT IN CARDIOGENIC)
4- vasopressors (norepinephrine) if patient remains hypotensive
5- specific treatment based on type of shock -> cardiogenic -> cath lab
-> septic -> antibiotics

Question 7

What are the treatment targets for undifferentiated shock patients?

Answer 7

• heart rate -> resolution of compensatory tachycardia
• blood pressure -> MAP > 65mmHg
• urine output -> > 0.5 mL/kg/hr
• lactate -> 2 or less

Question 8

What are the findings of cardiogenic shock?

Answer 8

• marked persistent hypotension > 30 mins -> SPB <90mmHg
• Cardiac index <2 - 2.2 L/min/M2
• PCWP > 18mmHg
• serum lactate > 2
• low urine output
• rising creatinine

Question 9

What are the causes of cardiogenic shock?

Answer 9

• ACS/ acute MI
• valvular diseases -> mitral or aortic regurgitation
• electrical causes -> arrhythmias
• extra cardiac -> blunt trauma, drugs, tamponade

Question 10

What are the clinical features of cardiogenic shock?

Answer 10

• cold clammy extremities
• poor capillary refill
• elevated JVP & distended neck veins
• pulmonary congestion
• features of heart failure
• underlying etiology features
• congestion -> wet & cold
• no congestion -> dry & cold

Question 11

What diagnostics are done to confirm cardiogenic shock?

Answer 11

• increased BNP
• ECG -> MI, cardiac arrhythmias, ventricular hypertrophy
• increased troponins in acute coronary syndrome
• ECHO -> valvular lesions, ventricular dysfunction, pericardial effusion
• Swan-Ganz catheter for hemodynamic monitoring

Question 12

How is cardiogenic shock managed?

Answer 12

1- ABCs
2- identify & treat underlying cause
3- preload reduction in case of volume overload -> loop diuretics, dialysis, nitroglycerin
4- inotropy -> dopamine or norepinephrine
5- after load reduction -> sodium nitroprusside, hydralazine
6- IV fluids ONLY if cold & dry
7- advanced mechanical support measures for refractory shock -> IABP & ECMO