Butorphanol for the relief of shivering associated with extradural anesthesia in parturients.

STUDY OBJECTIVE: To assess the efficacy of butorphanol for the relief of shivering following the epidural administration of 2% lidocaine. DESIGN: Randomized, double-blind study. SETTING: Labor and delivery department of a university-affiliated hospital inpatient facility. PATIENTS: Sixty-one healthy labor patients. INTERVENTIONS: Patients who had sustained shivering associated with lidocaine epidural anesthesia were given normal saline or butorphanol 1 mg. Patients were observed for 20 minutes following the administration of a study solution. MEASUREMENTS AND MAIN RESULTS: Shivering ceased within a mean time of 12.9 +/- 3.8 minutes in approximately 81% of the patients who received epidural butorphanol (p < 0.01), while 3% of the patients in the placebo group had no shivering following the administration of epidural saline. No sedation or changes in fetal heart rate were associated with epidural butorphanol. CONCLUSIONS: Epidural butorphanol is effective in the treatment of postepidural shivering associated with epidural lidocaine. Epidural agonist opioids have been reported to be efficacious in the management of postepidural shivering. This study demonstrated that a partial agonist opioid also is effective in the treatment of postepidural shivering.

Sensory evoked facial muscle electromyography for the quantification of acute labor pain.

Assessment of the adequacy of epidural analgesia for acute pain management can be difficult on occasion. This investigation used non-invasive sensory evoked facial muscle electromyography (SEFE) as well as a Verbal Assessment Scores (VAS) to assess severe pain in healthy parturients during the first stage of active labor. Institutional Review Board approval and patient informed consent were obtained from 12 healthy parturients who were in active labor and who had requested epidural analgesia for labor pain. SEFE microvoltage was recorded prior to epidural placement when a patient reported severe pain and again when a patient reported no pain with a subsequent uterine contraction. VAS assessments (0 = no pain and 10 = the worst pain ever experienced) were also recorded at identical time intervals. Statistical analysis was done using the paired two tailed Student's t-test. Each patient served as their own control. A statistically significant decrease in SEFE microvoltage (p < 0.001) was noted when analgesia was established (VAS = 0) in each patient. It was concluded in this pilot study that SEFE can be effective in quantifying acute severe nociception and thus can provide a continuous objective indicator of the effectiveness of analgesic regimens in an acute obstetric pain setting. Its applicability in other acute pain areas remains to be investigated.

Transient bradycardia associated with extradural blood patch after inadvertent dural puncture in parturients.

We have studied prospectively 10 ASA I or II postpartum patients after inadvertent dural puncture during labour. An extradural blood patch (autologous blood 15 ml) was performed within 18 h of delivery, with continuous EEG, upper facial EMG (Datex: Anesthesia and Brain Activity Monitor), pulse oximetry and heart rate measurement before, during and for 30 min after extradural injection. Non-invasive arterial pressure measurements (Dinamap) were recorded at 5-min intervals. After extradural blood patch, a statistically significant (Student's t test, P < 0.05) decrease in heart rate, from a mean baseline of 88.6 (SD 7.31) beat min-1 to 51.3 (7.6) beat min-1, occurred within 122.6 (16.9) s from the time of the EBP. Bradycardia was observed for a mean duration of 12.4 (1.1) s. Upper facial EMG, EEG, SpO2 and arterial pressure did not change.