Fluid Prescribing Patterns in the Intensive Care Unit

Abstract

This retrospective chart review characterizes the prescribing patterns of intravenous fluids in the medical and surgical intensive care unit. The charts of 130 patients, 65 from the MICU and 65 from the SICU, were reviewed over 4 days. There is a larger average fluid rate and variation on Day 1 compared to Day 4 though it was not significant (P = 0.023). The SICU group had an overall larger rate throughout the 4 days compared to the MICU although the difference was not significant (P = 0.064). The SICU group had a larger total daily amount compared to the MICU (P = 0.018). The MICU shows a mean fluid balance closer to net even than the SICU (P = 0.018), although both groups have a wide variation. Most patients (78/130) were net positive overall throughout the 4 days. Of the fluid composition, all patients received NS and D5W throughout their admission either in the form of fluids for volume replacement or accompanied with medications. 47% received LR in addition NS and D5W, mostly in the form of boluses. 31% received some other fluid in addition to NS and D5W. 22% received NS, D5W, LR and another fluid. SICU patients got more of each fluid overall. Lastly, 60/130 patients received a fluid bolus at any time during the 4 days. It was exclusively in the form of NS or LR and ranged from 100 mL to 1000 mL. No notes documented the use of fluids as “maintenance fluid” although all patients had some sort of intravenous fluid running at any instantaneous moment in time. Fluid boluses or continuous fluids intended for resuscitation were only documented 43% of the time in notes. There is only documentation of resuscitation fluids 43% of the time they are given and often in the setting of a clinical exam reported to be “euvolemic”. This study shows the highly variable fluid prescribing patterns in the intensive care unit. Given the literature suggesting the impact of positive fluid balances on outcomes, a more prudent approach to fluid and electrolyte balance is warranted.