Associations Between Perioperative Crystalloid Volume and Adverse Outcomes in Five Surgical Populations

Background: Optimal administration of fluids is an important part of enhanced recovery after surgery (ERAS) protocols. We sought to examine the relationship between perioperative crystalloid volume and adverse outcomes in five common types of surgical procedures with ERAS fluid guidelines in place where large randomized controlled trials have not been conducted: breast reconstruction, bariatric, major urologic, gynoncologic, and head and neck oncologic procedures.

Methods: This retrospective cohort study included patients who had undergone any one of the aforementioned procedures within any facility in a large multihospital alliance (Premier, Inc, Charlotte, NC) between 2008 and 2014. We used multivariable generalized additive models to examine relationships between the total crystalloid volume (TCV) on the day of surgery and a composite adverse outcome of prolonged (>75th percentile) hospital or intensive care unit stay or in-hospital mortality. Models were constructed separately within each surgical category and adjusted for demographic, clinical, and hospital characteristics. Informed consent requirements were waived because deidentified data were used.

Results: We identified 83,685 patients within 312 US hospitals undergoing breast reconstruction (n = 8738), bariatric surgery (n = 8067), major urologic surgery (n = 28,654), gynoncologic surgery (n = 34,559), and head/neck oncology surgery (n = 3667). There was significant patient-independent variation in TCV. Probabilities of adverse outcomes increased at a TCV below 3 L and above 6 L for all types of surgeries except bariatric surgery, where larger volumes were associated with progressively better outcomes.

Conclusions and relevance: Relationships between TCV and adverse outcomes were generally J shaped with higher volumes (>6 L) associated with increased risk. As per current ERAS guidelines, it is important to avoid excessive crystalloid volume in most surgical procedures except for bariatric surgery.