Shortened preoperative fasting for prevention of complications associated with laparoscopic cholecystectomy: a meta-analysis

Abstract

Objective Routine fasting (12 h) is always applied before laparoscopic cholecystectomy, but prolonged preoperative fasting causes thirst, hunger, and irritability as well as dehydration, low blood glucose, insulin resistance and other adverse reactions. We assessed the safety and efficacy of a shortened preoperative fasting period in patients undergoing laparoscopic cholecystectomy. Methods We searched PubMed, Embase and Cochrane Central Register of Controlled Trials up to 20 November 2015 and selected controlled trials with a shortened fasting time before laparoscopic cholecystectomy. We assessed the results by performing a meta-analysis using a variety of outcome measures and investigated the heterogeneity by subgroup analysis. Results Eleven trials were included. Forest plots showed that a shortened fasting time reduced the operative risk and patient discomfort. A shortened fasting time also reduced postoperative nausea and vomiting as well as operative vomiting. With respect to glucose metabolism, a shortened fasting time significantly reduced abnormalities in the ratio of insulin sensitivity. The C-reactive protein concentration was also reduced by a shortened fasting time. Conclusions A shortened preoperative fasting time increases patients' postoperative comfort, improves insulin resistance, and reduces stress responses. This evidence supports the clinical application of a shortened fasting time before laparoscopic cholecystectomy.

Keywords: Shortened preoperative fasting; complications; laparoscopic cholecystectomy; meta-analysis.

Figure 1.

PRISMA flow diagram.

Figure 2.

Methodological quality of trials included in the meta-analysis. Risk-of-bias graph and summary.

Figure 3.

Results of operative risk and gastric volume index in assessment of shortened fasting time. Forest plot showing that a shortened fasting time significantly reduced the operative risk (lg(risk ratio), −0.74; 95% confidence interval, −1.36 to −0.12; P = 0.019), but had no significant effect on gastric volume (standardized mean difference, −0.31; 95% confidence interval, −0.83 to 0.21).

Figure 4.

Results of subjective sensation index in assessment of shortened fasting time. Forest plot showing that a shortened fasting time significantly reduced postoperative pain (standardized mean difference, −0.89; 95% confidence interval [CI], −1.29 to −0.50; P = 0.000), postoperative nausea and vomiting (lg(odds ratio [OR]), −0.24; 95% CI, −0.48 to −0.00; P = 0.046) and intraoperative vomiting (lg(OR), −0.47; 95% CI, −0.71 to −0.22; P = 0.000), but had no significant effect on intraoperative nausea (lg(OR), −0.33; 95% CI, −0.72 to 0.06).

Figure 5.

Results of glucose metabolism index in assessment of shortened fasting time. Forest plot showing that a shortened fasting time significantly reduced abnormalities in the ratio of insulin sensitivity (lg(odds ratio), −0.66; 95% confidence interval [CI], −1.31 to −0.01; P = 0.046) and reduced the postoperative glucose concentration (standardized mean difference [SMD], −0.84; 95% CI, −1.67 to −0.00; P = 0.049), but had no significant effects on the insulin concentration or homeostatic model assessment–insulin resistance (HOMA-IR) (insulin: SMD, −0.09; 95% CI, −0.94 to 0.75 and HOMA-IR: SMD, −1.25; 95% CI, −2.62 to 0.12).

Figure 6.

Results of stress response index in assessment of shortened fasting time. Forest plot showing significant differences in the C-reactive protein and carnitine concentrations between the shortened fasting and control groups (standardized mean difference [SMD], −1.42; 95% confidence interval [CI], −2.33 to −0.51; P = 0.002 and SMD, −0.99; 95% CI, −1.75 to −0.23; P = 0.011, respectively).

Figure 7.

Funnel plots of publication bias. Begg and Egger tests provided no evidence of significant publication bias in most outcome assessments except gastric volume (Egger test, P = 0.000; Begg test, P = N.S.), glucose (Egger test, P = 0.001; Begg test, P = 0.004) and homeostatic model assessment–insulin resistance (Egger test, P = 0.035; Begg test, P = N.S.).