[A Systematic Review and Meta-Analysis of the Pros and Cons of Consuming Liquids Preoperatively]

Preoperative anesthesia long time fasting, may increase patient hemodynamic instability during surgery and may affect the patient's post-surgery electrolyte balance. No meta-analysis has been conducted to explore the effects of preoperative liquid intake amount on gastric fluid PH, gastric fluid volume, surgery inhalation of pulmonary complications, and patient self-perceptions quality of care systematic review and meta-analysis of the literature.

To assess the pros and cons of preoperative liquid intake using a systematic review of the literature.

The authors searched ten databases including NRC (Nursing Reference Center), CINAHL (Cumulative Index to Nursing and Allied Health Literature), WOS (Web of Science), PubMed, The Cochrane Library, UpToDate, DynaMed, NGC (National Guideline Clearinghouse), Airiti Library, and National Digital Library of Theses and Dissertations in Taiwan, to identify relevant articles that were published from 2003 to January 2017. Nine qualified articles were included in the analysis from the 30 articles that were selected using an initial keyword search. The Oxford Centre for Evidence-based Medicine 2011 Levels of Evidence was used as the evidence grade and the CASP (Critical Appraisal Skills Program) was used to evaluate the quality of the selected articles. The quantitative results were analyzed using Review Manager, Version 5.1.

The quality of the literature was medium to high. A small to moderate dose of fluid consumed at 2 hours prior to surgery did not significantly increase gastric fluid volume during anesthesia, with a combined effect of 2.37 (95% CI [-5.12, 9.85], p = .54), and had no effect on gastric fluid PH, with a combined effect of 0.10 (95% CI [0.00, 0.20], p = .05).

The results indicate that consuming a small to moderate dose of liquid at 2 hours prior to the provision of anesthesia does not significantly increase the gastric fluid volume or gastric fluid PH of patients during anesthesia. Moreover, the positive benefits of consuming this dose of liquid include reduced risks of aspiration pneumonia, gastroesophageal reflux disease, and postoperative complications as well as reduced perceptions of thirst and hunger during the immediate preoperative period. Thus, this analysis supports that the advantages of allowing patients to consume a moderate or smaller dose of liquid prior to surgery outweigh the disadvantages.