Fasting Before Cardiac Catheterization: Still Necessary? A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Background Fasting before elective or nonurgent coronary angiography is commonly recommended to reduce the risk of adverse events, such as aspiration pneumonia. This systematic review and meta-analysis aimed to evaluate the impact of fasting versus nonfasting protocols on patient outcomes and satisfaction. Methods We systematically searched PubMed, Embase, and Cochrane Library databases for randomized clinical trials comparing fasting and nonfasting states before cardiac catheterization. The primary outcome was a composite of adverse events including pneumonia, hypoglycemia, and nausea/vomiting. Secondary outcomes included individual adverse events and patient satisfaction. For each binary outcome we estimated crude event probabilities for each treatment arm. Next, we pooled study-specific results in meta-analyses using odds ratio (OR) and risk difference as effect measures for binary outcomes and standardized mean difference for satisfaction. Results We identified 8 randomized clinical trials, including a total of 3147 patients. Our meta-analysis showed no evidence of a difference in the incidence of composite adverse events between fasting and nonfasting groups in ORs (OR, 1.08, [95% CI, 0.78-1.51], where OR<1 favors fasting). The crude event probabilities were 4.9% and 4.4% for fasting and nonfasting groups respectively, with an estimated risk difference =0.4% (-1.1% to 1.8%), where risk difference <0 favors fasting. Patient satisfaction was found higher in nonfasting protocols, standardized mean difference 0.62 (0.11-1.13). Conclusion Our meta-analysis found no evidence that fasting before elective coronary angiography reduces adverse events. However, we found evidence that fasting reduces patient satisfaction. These findings question the necessity of fasting protocols in this context. REGISTRATION URL: https://www.crd.york.ac.uk/PROSPERO/view/CRD42024595465; Unique identifier: CRD42024595465.