Pulse perfusion index for predicting intrapartum fever during epidural analgesia

To assess whether pulse perfusion index (PI) values could be employed to predict intrapartum fever and to provide a cut-off PI value for predicting intrapartum fever occurrence.

We conducted a single-center, prospective, observational study.

Delivery room at the Department of Obstetrics, Affiliated Hospital of Jiangsu University.

117 parturients who intended to have a vaginal delivery.

Each parturient received epidural analgesia.

We checked each parturient's tympanic temperature before analgesia (T₀), at 1 h (T₁) and 2 h (T₂) after analgesia, immediately at the end of the second (T₃) and third (T₄) stages of labor, and at 1 h postpartum (T₅). A temperature of ≥38°C was defined as fever. PI, measured on the right second toe, was recorded before analgesia (PI₀) and at 10 min (PI₁₀), 20 min (PI₂₀), and 30 min (PI₃₀) after analgesia. The PI change rate was calculated as the incremental change in PI₃₀ from PI₀, divided by the PI₀. Receiver operating characteristic (ROC) curves were used to verify the utility of the PI₃₀ and PI change rate values for predicting intrapartum fever.

We found that peak temperature (T_P) occurred at the end of the second or the third stage of labor. Within 30 min after analgesia, the PI showed a significant increase over time and there was a linear correlation between PI₃₀ and T_P values (P < 0.001, r = 0.544). The PI₁₀, PI₂₀, PI₃₀ and PI change rate in febrile parturients were higher than those in afebrile parturients (P < 0.001). The area under the ROC (AUROC) for PI₃₀ was 0.818 (P < 0.001) with a cut-off of 9.30. The AUROC of the PI change rate was 0.738 (P < 0.001) with a cut-off of 3.45.

PI₃₀ and PI change rate values could be used to predict intrapartum fever in parturients after epidural analgesia.