Increased Serum Lactate in Peritoneal Dialysis Patients Presenting with Intercurrent Illness.

Background: Lactate is the most commonly used buffer in peritoneal dialysis (PD) solutions. While previous studies have shown that serum lactate is normal in stable PD patients, the purpose of our study was to evaluate whether abnormal lactate values are more common in PD patients presenting to the emergency department (ED) and have the same significance as in the general population.

Methods: This observational cohort study assessed the prevalence of elevated serum lactate in PD patients presenting to the ED and evaluated clinical factors associated with an abnormal lactate value.

Results: We studied 172 patient visits in 89 PD patients to the ED at a major academic center between January 1, 2015, and December 31, 2015. An initial venous blood lactate value was performed in 91 visits (53%) and was found to be elevated (> 2 mmol/L) in 26 cases (29%). While an abnormal lactate was associated with signs of hemodynamic compromise such as intensive care unit (ICU) admission (26.9% vs 10.8%, = 0.05) and tachycardia (46.2% vs 9.2%, < 0.01), in half of the cases with elevated lactate, there was no evidence of hemodynamic instability at initial presentation. Moreover, an abnormal lactate value was also associated with a greater likelihood of undergoing an abdominal computed tomography (CT) scan (46.2% vs 18.5%, < 0.01), but bowel ischemia was present in only 1 case.

Conclusion: An abnormal lactate value is often seen in PD patients presenting to the ED, even in the absence of signs of hemodynamic instability, and very rarely indicates bowel ischemia. We postulate that in the setting of an acute intercurrent illness, there is a transient disruption in the metabolism of lactate absorbed from the PD fluid. This novel observation suggests that elevated serum lactate in the sick PD patient does not necessarily indicate tissue hypoperfusion or gut ischemia and may obviate unnecessary investigations.