Meta-analysis of the effects of lidocaine on postoperative reflux in the horse

To determine the efficacy of lidocaine at reducing incidence of postoperative reflux (POR) in horses by using quantitative statistical analysis.

Systematic meta-analytical review.

Studies on horses undergoing gastrointestinal surgery for small intestinal lesions, identified by systematic search between 2001 and 2017.

A search with PubMed/MEDLINE, Web of Science, and Google Scholar was performed, followed by secondary searches of veterinary trade journals and bibliographies of relevant articles. The primary outcome measure for this study was the effect of lidocaine therapy on the odds of POR. Subgroup analysis assessed included the timing of lidocaine therapy, incidence of mortality, and incidence of repeat celiotomy. A meta-analysis was performed with a random effects model, with the effect size calculated as an odds ratio (OR) with 95% confidence intervals (CI). Statistical significance was set at P < .05.

Among 1933 peer reviewed publications that met the initial search criteria, 12 relevant studies were available for analysis. Lidocaine was associated with an increased incidence of diagnosis of POR (OR 6.3, 95% CI [1.4, 27.0], P = .01). Horses treated with lidocaine were more likely to survive to discharge (OR 6.8, 95% CI [3.9, 11.7], P < .01).

Lidocaine was associated with an increased survival rate in horses undergoing exploratory celiotomy for small intestinal disease according to this meta-analysis of the recent literature.

This body of published evidence provides support to administer lidocaine in horses to improve survival rather than preventing POR.