approached significanceP = 0.056
The Friedman test revealed that the respiratory duration was significantly different in the last 1 min prior to, 0.5–1.5 min after, and 14–15 min after changing of the perfusate ( P = 0.030); the difference between the respiratory duration during the last 1 min prior to changing of the perfusate and the duration during the first 0.5–1.5 min after switching approached significance ( P = 0.056, Wilcoxon).