S3268 The Next Step: An Analysis of Patients’ Disposition in Context of Hyperammonemia

Abstract

INTRODUCTION: Altered mental status is among the most frequently seen reasons forpresentation to emergency departments nationwide. As part of the workup, ammonia levels are often checked due to the long-standing belief that there is a direct causal relationship between elevated ammonia levels and mental status. Based on this, the treatment plan is frequently directed towards lab values rather than the clinical picture leading to substantial overuse of healthcare resources. In this study, we aimed to track the disposition of patients from a community hospital emergency department based on their ammonia levels and clinical presentation. METHODS: We performed a retrospective chart review of 190 patients seen in a community hospital. The database comprised of all patients seen over a period from July to August 2019 at a community hospital with an ICD 10 diagnosis code of altered mental status, unspecified (R41.82) as well as hepatic failure, unspecified without coma (K72.90) and unspecified cirrhosis of liver (K74.60). Data points including patient age, documented history of cirrhosis, documented AMS, ammonia level on presentation, trend of ammonia levels, length of stay, and disposition form the ED. The study was approved by the institutional board review committee of our hospital. RESULTS: Out of a total 190 patients who met criteria, approximately 140 presented with ammonia levels >45. Out of this cohort, 12% were discharged directly from the ER. In contrast, approximately 19% of the patients with ammonia levels ≤45 on presentationwere discharged from the ED. For those admitted to the hospital from the ED, the average length of stay was 5.84 days vs. 4.98 days for those with ammonia levels >45 vs. ≤45 respectively. CONCLUSION: As multiple studies have shown, the relationship between altered mental status and hyperammonemia isn’t as clear-cut as previously thought. Furthermore, deviations of the cutoff value of 15–45 µ/dL for normal ammonia level doesn’t truly reflect each individual clinical scenario. Providers can be further educated on the utility of basing patient disposition, and thereby hospital length-of-stay to optimize resources, on multiple factors with serum ammonia level being just one of many. The limitations of this study were that it was a retrospective analysis, single-center study.Table 1