One of the mantras my attending emphasizes with regards to critical care deals with the timing of our interventions. In critical care, there’s “a time to give and a time to take.” So what does this mean? Well let’s address a common scenario:
Patients who decompensate and become hypotensive (low blood pressure) refractory to fluid boluses are often moved to the ICU for higher level of care. We place arterial lines, start vasopressors, and bolus tons of fluid. In this sense, it’s a time to be less judicious about fluid (“time to give”). Furthermore, more fluid is usually administered in the form of electrolyte repletion and antibiotics. These steps are essential to correct for hypoperfusion and metabolic abnormalities which can otherwise be catastrophic to the body’s organs, but as the underlying illness resolves, you’re left with liters of accumulated fluid causing swelling and pulmonary edema. Now it’s “time to take” with careful diuresis. I’ve preferred using Lasix drips (for ease of titration) with a single dose of metolazone to open up the flood gates and let those kidneys do their job! 🙂
When I first started this rotation, I thought this sequence of events seemed wasteful in terms of cost and time – “hey, let’s bolus a ton of fluid just so we can diurese it later.” But after two weeks of ICU time, it’s a generally well tolerated approach in critically ill patients. So yes, timing is everything.