Does a Combined Intravenous-volatile Anesthesia Offer Advantages Compared to an Intravenous or Volatile Anesthesia Alone

A Systematic Review and Meta-analysis


BMC Anesthesiol. 2021;21(52) 

In This Article


Search Strategy

We screened 19,036 records, of which 30 were intensively evaluated (see Figure 1). Ten studies provided data on the occurrence of PONV in the PACU/RR, PONV within 24 h, time to extubation, movement during surgery, pain intensity in the PACU/RR and pain intensity within 24 h. All included studies provided data on PONV,[4–13] five on time to extubation,[5,6,8,9,13] two on movement during surgery[6,8] and four on postoperative pain.[4,6,7,10] Liang et al.[9] and Chen et al.[4] presented their data on pain only categorized, whereas Hensel et al. provided data only as median with confidence interval.[6] The corresponding authors of these studies were contacted via the email address given in the publication and were kindly asked to provide us with the mean values and standard deviations. The only author who responded was Dr. Hensel[6] whom we thank.

Figure 1.

PRISMA flow diagram displaying the search and extraction process

Included Studies and Participants

Ten studies with 16 treatment arms and 1960 participants were included. These studies reached a mean value of 5.7 points (standard deviation 1.1) and a median of 6 points (range 3–7) in the Delphi list for quality assessment.[14] For a detailed overview, see Supplementary Table 1. A detailed overview of the included studies is given in Table 1.


Four studies with six treatment arms[4,7,9,11] provided data on PONV in the PACU/RR (three arms each CIVA vs. BAL and CIVA vs. TIVA). The overall risk for PONV in the PACU/RR was significantly reduced for the CIVA group (RR 0.657, CI 0.502–0.860, p-value 0.002), compared to the BAL group. Thus, CIVA showed a significant risk reduction for PONV in the PACU/RR (RR 0.514, CI 0.364–0.725, p-value 0.000). Comparing CIVA to TIVA no difference between the groups (RR 0.970, CI 0.629–1.497, p-value 0.892) was found. There was no heterogeneity (Q-value 6.74, df (Q) 5, p-value 0.24, I2 25.86).

The risk for PONV within 24 h postoperatively is shown in Figure 2. A significant heterogeneity (Q-value 29.86, df (Q) 13, p-value 0.00, I2 56.47) was found. In a sensitivity analysis we removed the only non-randomized study[6] which had only TIVA as control. The subgroup compared to TIVA showed no significant change (RR 0.980, CI 0667–1.440, p-value 0.916).

Figure 2.

PONV within 24 h

Results on time to extubation are shown in Figure 3. Here we found a significant heterogeneity (Q-value 126.63, df (Q) 5, p-value 0.00, I2 96.05). In a sensitivity analysis the non-randomized study was removed, but the TIVA subgroup (SMD -0.026, CI -0.319 – 0.267, p-value 0.860) nor the overall results (SMD -0.052, CI -0.342 – 0.239, p-value 0.727) were significantly altered.

Figure 3.

Time to extubation

Only two studies provided data on movement during surgery.[6,8] Both studies used TIVA as a control group and both studies point in the same direction leading to a significant overall result in favor of CIVA (RR 0.241, CI 0.135–0.428, p-value 0.000). No heterogeneity was found (Q-value 0.31, df (Q) 1, p-value 0.57, I2 0.00). Since only two studies were included in this analysis, we have omitted the sensitivity analysis.

Two studies with three treatment arms provided data on pain in the PACU/RR.[6,7] There was neither a significant difference between CIVA and balanced anesthesia (SMD -0.181, CI -0.610 – 0.248, p-value 0.408) nor between CIVA and TIVA (RR 0.071, CI -0.086 – 0.228, p-value 0.376). The results of the subgroup reflect the overall effect without significant difference (SMD 0.041, CI -0.106 – 0.188, p-value 0.585). We found no heterogeneity (Q-value 1.21, df (Q) 2, p-value 0.55, I2 0.00). The removal of the non-randomized study did not significantly alter the overall effect (SMD -0.034, CI -0.337 – 0.269, p-value 0.825).

The results for pain in a period of 24 h after surgery are shown in Figure 4. We found no heterogeneity (Q-value 3.16, df (Q) 3, p-value 0.37, I2 5.17). The removal of the only non-randomized study had no significant impact on the overall results (SMD -0.072, CI -0.290 – 0.146, p-value 0.519).

Figure 4.

Pain within 24 h post surgery