Effect of volatile and intravenous anesthesia on long-term survival of cancer surgery patients: a systematic review and meta-analysis

AbstractBackground The impact of volatile anesthesia (INHA) and total intravenous anaesthesia (TIVA) on the long-term survival of patients after oncology surgery is a subject of controversy. The purpose of this study was to make overall evaluation of the association between these two anesthetic techniques and long-term prognosis of oncology patients after surgery. Methods Databases were searched according to the PRISMA guidelines up to September 30, 2018. Hazard ratios (HRs) with its 95% confidence intervals (CIs) were calculated after multivariable analyses and propensity score (PS) adjustments. Eight retrospective cohort articles reporting data on overall survival (OS) and recurrence-free survival (RFS) were included. An inverse variance random effects meta-analysis was conducted. The Newcastle Scale was used to assess methodological quality and bias. Results In total, about 18922 cancer patients observed were included in the meta-analysis, of which 10433 cases were available for analysis in INHA and 8489 in TIVA group. Compared to TIVA, INHA showed a shorter OS (HR =1.27, 95% CI 1.069 to 1.516, p=0.007), with a medium heterogeneity (Q-test p=0.003, I-squared=67.6%). However, no significant differences were identified between INHA and TIVA group (HR =1.10, 95% CI 0.729 to 1.659, p=0.651) concerning RFS albeit from a limited data pool. When a subgroup analysis was performed by race, the association was more likely to be observed in the Asian studies (HR=1.46, 95%CI 1.19–1.8, p =0.00), with a much lower heterogeneity (Q-test p=0.148, I-squared=44%). When comparison was done only in breast cancer patients, no significant differences were found for OS (HR=1.625, 95%CI 0.273-9.67, p=0.594) between INHA and TIVA. Conclusion TIVA for cancer surgery might be associated with better OS compared to INHA. The effect of INHA and TIVA on OS and RFS in the perioperative setting remains uncertain, cancer-specific, and has low-level evidence at present. Randomized controlled trials are required in future work. Registry number The review protocol was registered with PROSPERO (Registration NO.CRD42018109341).