Effect of Local Anesthetic Solution at Different Temperatures for Epidural Labor Analgesia on Intrapartum Fever: A Randomized Clinical Trial.

In 30 seconds

This double-blind randomized controlled trial compared warmed (37°C) with room-temperature (22°C) epidural local anesthetic in 220 nulliparous parturients receiving labor analgesia. Intrapartum fever (≥38°C) occurred in 15.5% (17/110) of the warmed group versus 30.9% (34/110) of the room-temperature group (RR 0.5 [95% CI, 0.298-0.840]; P = .007). Maximum temperature was also lower with warmed solution. However, the observed fever reduction did not meet the trial’s preset threshold for a clinically meaningful 60% reduction, and other assessed outcomes did not differ significantly.

Key findings

• Fever incidence was 15.5% (17/110) with warmed solution versus 30.9% (34/110) at room temperature (RR 0.5 [95% CI, 0.298-0.840]; P = .007).
• Maximum temperature was 37.4 (IQR, 37.2-37.7) °C versus 37.6 (IQR, 37.3-38.0) °C; median difference -0.2 (95% CI, -0.3 to -0.1) °C (P = .006).
• Shivering incidence did not differ significantly: 10.9% (12/110) versus 14.5% (16/110) (P = .418).
• The fever reduction did not reach the preset clinically meaningful threshold of 60%; no significant differences were found in other assessed secondary outcomes.

Why it matters

Intrapartum fever was less frequent when epidural local anesthetic was warmed in this randomized comparison, suggesting solution temperature may influence maternal temperature during labor. The result is clinically relevant to evaluating fever prevention, but the observed reduction fell short of the trial’s prespecified meaningful threshold, and the study found no significant differences in neonatal outcomes or other assessed secondary outcomes.

What to keep in mind

The trial enrolled nulliparous parturients aged 18-35 years with term singleton pregnancies, limiting direct generalization beyond this population. The observed fever reduction did not meet the prespecified clinically meaningful threshold.