Fluid balance is challenging to manage in BMT patients. Multiple infusions (drug, iv fluids, blood products, TPN) frequently contribute to a positive fluid balance, while impairment in kidney function (e.g., from drugs), low albumin (e.g., from poor nutrition), and inflammation (i.e., causing capillary leak) contribute to fluid retention.
Volume overload causes many complications including liver damage (veno-occlusive disease) and shortness of breath (pulmonary edema). In addition, volume overload can result in excessive lower extremity edema, which may cause discomfort as well as play a role in falls (trouble walking due to edema) and promote immobility. Immobility in turn can contribute to wounds (decubitus ulcers) and deconditioning.
To maintain fluid balance (ins=outs, or I=O), providers may use diuretics to flush out fluid. However, care must be taken given the multiple nephrotoxic agents patients are on (e.g., cyclosporine, tacrolimus) and to avoid causing acute kidney injury with overuse of diuretics. Provider strategies for diuretic management varies, with some insisting on strict daily I/O and weight measurements, with titration of diuretic dose to achieve net even, while others take a more liberal strategy.