Shock Solution 13

The fluid loading appears complete, but the dopamine is having a disastrous effect: the last thing a patient needs following a myocardial infarction is a tachycardia of 140. I would insert a pulmonary artery catheter (PAC) to find out what this patient’s left sided filling pressures are and what his cardiac output is.

You insert a PAC which yields a cardiac output of 2.2 liters, stroke volume of 35ml a pulmonary capillary wedge pressure of 18, and a mixed venous oxygen saturation of 56%. What do you think?
 

The low cardiac output is a result of a very low stroke volume, which appears inappropriate in the setting of sepsis (his ejection fraction must be very low indeed): the patient is in cardiogenic shock, with a probable peripheral vasoplegia. He appears fully volume loaded. What we need is an agent that will cause peripheral vasoconstriction – to bring the total peripheral resistance back towards normal, improve cardiac contractility and slow down the heart simultaneously, without increasing myocardial oxygen demand. An intra-aortic balloon pump may be a good idea (there is no access to the femoral areas following surgery). An alternative strategy is to put the patient on a combination of dobutamine and norepinephrine – the former titrated against cardiac output, the latter against blood pressure.

Using this strategy on dobutamine 5mic/kg/min and norepinephrine 2.0mic/min, the patient’s blood pressure rose to 120/70, cardiac output to 4.5 liters / min, stroke volume of 70ml and starts to put out urine.

Dx: distributive shock, hypotension, complicated by myocardial ischemia and cardiogenic shock.