Better haemodynamic stability under xenon anaesthesia than under isoflurane anaesthesia during partial nephrectomy - a secondary analysis of a randomised controlled trial

Abstract

Background: Renal dysfunction following intraoperative arterial hypotension is mainly caused by an insufficient renal blood flow. It is associated with higher mortality and morbidity rates. We hypothesised that the intraoperative haemodynamics are more stable during xenon anaesthesia than during isoflurane anaesthesia in patients undergoing partial nephrectomy.

Methods: We performed a secondary analysis of the haemodynamic variables collected during the randomised, single-blinded, single-centre PaNeX study, which analysed the postoperative renal function in 46 patients who underwent partial nephrectomy. The patients received either xenon or isoflurane anaesthesia with 1:1 allocation ratio. We analysed the duration of the intraoperative systolic blood pressure decrease by > 40% from baseline values and the cumulative duration of a mean arterial blood pressure (MAP) of < 65 mmHg as primary outcomes. The secondary outcomes were related to other blood pressure thresholds, the amount of administered norepinephrine, and the analysis of confounding factors on the haemodynamic stability.

Results: The periods of an MAP of < 65 mmHg were significantly shorter in the xenon group than in the isoflurane group. The medians [interquartile range] were 0 [0-10.0] and 25.0 [10.0-47.5] minutes, for the xenon and isoflurane group, respectively (P = 0.002). However, the cumulative duration of a systolic blood pressure decrease by > 40% did not significantly differ between the groups (P = 0.51). The periods with a systolic blood pressure decrease by 20% from baseline, MAP decrease to values < 60 mmHg, and the need for norepinephrine, as well as the cumulative dose of norepinephrine were significantly shorter and lower, respectively, in the xenon group. The confounding factors, such as demographic data, surgical technique, or anaesthesia data, were similar in the two groups.

Conclusion: The patients undergoing xenon anaesthesia showed a better haemodynamic stability, which might be attributed to the xenon properties. The indirect effect of xenon anaesthesia might be of importance for the preservation of renal function during renal surgery and needs further elaboration.

Trial registration: ClinicalTrials.gov : NCT01839084. Registered 24 April 2013.

Keywords: Haemodynamic stability; Isoflurane; Nephroprotection; Renal function; Xenon.

Conflict of interest statement

MC and RR declare that they have received lecturer and consultant fees from Air Liquide Santé International. MC and RR declare that they have ongoing consultancy contracts with Air Liquide Santé International and Baxter. AK declares that she has received travel reimbursements by Air Liquide Santé International. PS and AF declare that they have no financial competing interests. All authors declare that they have no non-financial competing interests.

Figures

Fig. 1

The flowcharta of this secondary analysis aThe flowchart was modified according to the PaNeX study for partial nephrectomy with xenon

Fig. 2

Intraoperative heart rate Intraoperative heart rate in the xenon and isoflurane groups at different time points. The data were analysed using the Mann-Whitney U test and are presented as means ± standard deviation. *P-value < 0.05

Fig. 3

Intraoperative norepinephrine consumption Cumulative intraoperative norepinephrine consumption in the xenon and isoflurane groups, presented as median with interquartile ranges. Individual data are presented as closed circles and squares. The data were analysed using the Mann-Whitney U test

Fig. 4

Level of anaesthesia Level of anaesthesia measured by BIS monitoring in the xenon and isoflurane groups at different time points. BIS, bispectral index. The data were analysed using the Mann-Whitney U test and are presented as means ± standard deviation. *P-value < 0.05; **P-value < 0.01

Fig. 5

Intraoperative systolic blood pressure Systolic blood pressure in the xenon and isoflurane groups at different time points. The data were analysed using the Mann-Whitney U test and are presented as means ± standard deviation. *P-value < 0.05; **P-value < 0.01