Describe throle of cardiac output measurement in Intensive Care, including  indications, and how it may change therapy.

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College Answer

The role of cardiac output measurement  depends  largely on local practice. Units will vary in both aggressiveness of determination of cardiac output (PA catheter, echocardiography etc.), and in the way that the information is used (targeting particular goals, having monitoring protocols). Much of our haemodynamic and respiratory management can be done without regular assessment of cardiac output.  The levels  of  evidence  to  support  roles, indications  and  changes  in  therapy  should  be provided

Discussion

This complicated question did not merit a very detailed college answer, forcing me to elaborate upon this by myself.

One must be aware that the question refers to the role of cardiac output measurement in the ICU - not the merits of each specific method, or the risks vs benefits of cardiac output monitoring techniques.

Of course, how the hell do you provide levels of evidence for that?

Here is a table instead.

Indications for cardiac output monitoring

Influence on management

Deranged cardiac function in the context of shock

Titration of fluids, inotropes and vasopressors

Goal-directed resuscitation of complex multifactorial shock states

Continuous  monitoring following cardiac and non-cardiac surgery for high risk patients

Early intervention for depressed cardiac function

Protocol-driven  management of  hemodynamically unstable patients

Standardised management algorithms driven by cardiac output monitoring can support management decisions

References

References

Mathews, Lailu, and Kalyan RK Singh. "Cardiac output monitoring." Annals of cardiac anaesthesia 11.1 (2008).

de Waal, Eric EC, Frank Wappler, and Wolfgang F. Buhre. "Cardiac output monitoring." Current Opinion in Anesthesiology 22.1 (2009): 71-77.

Pinsky, Michael R. "Hemodynamic evaluation and monitoring in the ICU."CHEST Journal 132.6 (2007): 2020-2029.