Impact of an enteral nutrition holding guideline on daily nutrition goals in patients taking phenytoin.

BACKGROUND: Concomitant administration of enteral nutrition (EN) and phenytoin decreases phenytoin absorption. Concerns over impaired nutrition, however, may prevent EN from being held surrounding phenytoin administration. This study aimed to evaluate whether EN holding guidelines impacted nutrition goal achievement in patients taking phenytoin. METHODS: Adult patients administered enteral phenytoin for acute or chronic seizures while receiving EN during a neurocritical care admission 6 months before and after EN holding guideline implementation were eligible. Patients without phenytoin concentrations or a clinical registered dietitian assessment were excluded. The primary outcome was the percentage of nutrition daily goals attained before and after implementation. Secondary end points included the incidence of hypoglycemia, differences in measured phenytoin concentrations, and rates of therapeutic (10-20 mcg/ml) and high-therapeutic (15-20 mcg/ml) concentration attainment. Concentrations were adjusted for hypoalbuminemia using the Winter-Tozer equation. RESULTS: Fifty-five patients representing 412 patient days and 1110 phenytoin administrations were included with 29 preimplementation and 26 postimplementation patients. Median percent attainment of daily EN goals was consistent preimplementation and postimplementation (86% vs 83%, P = 0.48). No significant change in rates of days with hypoglycemia was observed. Adjusted phenytoin concentrations were similar before and after implementation (14.1 vs 15.2 mcg/ml, P = 0.45), but the preimplementation cohort had a lower proportion of high-therapeutic concentrations (23% vs 36%, P = 0.018). CONCLUSION: Holding EN for phenytoin did not impact attainment of daily nutrition goals and was not associated with increased rates of hypoglycemia. This is the first study to evaluate the effect of EN holding on nutrition goals in patients receiving phenytoin.

Evaluation of Potential Drug-Drug Interactions in Adults in the Intensive Care Unit: A Systematic Review and Meta-Analysis.

INTRODUCTION: There is an increased risk of potential drug-drug interactions (pDDIs) in critically ill patients based on the number of drugs received. The occurrence of pDDIs and clinical significance is not well described. OBJECTIVE: The aim was to provide insight into important clinical issues and offer guidance on drug-drug interaction (DDI) surveillance through the performance of a systematic review. METHODS: Five targeted objectives were developed, a priori, which guided study selection and data abstraction. Two independent reviewers extracted the definition, frequency, type, and clinical significance of pDDIs. A meta-analysis was performed to evaluate the proportion of patients exposed to a pDDI. Three data sources (PubMed, Embase, and Scopus) were utilized for the search to include studies that evaluated pDDIs in adult critically ill patients. Included studies in the systematic review and meta-analysis were required to be full text. RESULTS: A total of 39 studies met inclusion criteria. Definitions of pDDIs were diverse. Frequency of pDDIs varied by study, but was most commonly between one and five pDDIs per patient. Fifty-eight percent of patients were exposed to at least one pDDI during their intensive care unit admission. Types of pDDIs identified were numerous, with aspirin being the most common drug involved. As expected, not all pDDIs were clinically significant. Clinical significance was determined by varied definitions and sources. CONCLUSIONS: Improving the understanding of clinically significant pDDIs and alerts that clinicians encounter may guide better development of surveillance through clinical decision support and decrease alert fatigue.