Addition of dextrose 3.5% to intrathecal sufentanil for labour analgesia reduces pruritus.

PURPOSE: To determine whether the addition of a low concentration (3.5%) of dextrose would minimize pruritus while maintaining the quality of analgesia. METHODS: In a double blind study 48 parturients in early labour were randomized to one of two study groups: dextrose (Dex, n = 24; 10 microg sufentanil in dextrose 3.5%), or normal saline (NS, n = 24; 10 microg sufentanil in normal saline). Parturients received the study drug as the intrathecal injection of the combined spinal-epidural (CSE) technique for labour analgesia. Duration and degree of analgesia were measured until epidural analgesia was initiated or delivery of the baby. The intensity and distribution (above T6, T6-L1, and below L1) of pruritus were measured at five minute intervals during first 25 min after injection. RESULTS: Quality and duration of analgesia did not differ between groups, but the overall incidence of pruritus was less in the Dex group (88% vs 42%, P = 0.001). Within each region, the incidence of pruritus was less in the Dex group. In patients who had pruritus, for the Dex group, the incidence of pruritus in the upper region (>T6) was lower than the NS group. There was no difference in the lower regions. CONCLUSION: The addition of dextrose 3.5% to intrathecal sufentanil reduced the incidence of pruritus without affecting the duration or quality of analgesia in parturients in early labour. The distribution of pruritus in the Dex group was limited to below T6 suggesting that pruritus to intrathecal sufentanil is mediated at the spinal level.

Ondansetron versus placebo for the control of nausea and vomiting during Caesarean section under spinal anaesthesia.

This prospective, randomised, placebo-controlled, double-blind study was performed to evaluate the effects of ondansetron on nausea and vomiting during elective Caesarean section under spinal anaesthesia. Seventy-four full-term parturients were studied. After umbilical-cord clamping, ondansetron 4 mg or 0.9% saline was injected intravenously and the study period continued for 2 h. The severity of nausea was graded from 0 = none to 10 = maximum, while that of vomiting was graded from single = once per min to continuous = multiple per min. The incidence of vomiting was lower following ondansetron (36%) compared with the control group (58%, p < 0.028). Neither the severity of vomiting nor the incidence of nausea was influenced by ondansetron. However, for those who experienced nausea, ondansetron reduced its severity (p = 0.05). We conclude that the intra-operative administration of 4 mg ondansetron intravenously during Caesarean section under spinal anaesthesia significantly reduces the incidence of vomiting and the severity of nausea.

Rapacuronium for modified rapid sequence induction in elective caesarean section: neuromuscular blocking effects and safety compared with succinylcholine, and placental transfer.

We have compared rapacuronium 2.5 mg kg-1 (n = 20) with succinylcholine 1.5 mg kg-1 (n = 22) in a multicentre, blinded, randomized study in full-term parturients undergoing elective Caesarean section under general anaesthesia. Thiopental 5 mg kg-1 was given i.v. followed by the neuromuscular blocking agent. Sixty seconds later intubation was performed. Intubating conditions, evaluated as excellent, good or poor, were good to excellent in 95% and 91% in the intent-to-treat patients after rapacuronium and succinylcholine, respectively (ns). Mean onset times at the adductor pollicis muscle for rapacuronium and succinylcholine were 80.4 (SEM 14.4) s and 63.9 (5.6) s (ns) while maximum block was 96 (1.9)% and 99 (0.4)%, respectively (ns). Rate of recovery was significantly longer after rapacuronium; times for return of T1 to 25% were 16.9 (1.5) min and 9.6 (1.1) min for rapacuronium and succinylcholine, respectively (P = 0.0004). Maternal side effects included more tachycardia and skin erythema with rapacuronium; no maternal mortality or morbidity, including bronchospasm, occurred in either group. There were no neonatal adverse effects in either group based on: Apgar scores at 1 and 5 min; times to sustained respiration; neuroadaptive capacity scores at 15 min, 2 h and 24 h; and umbilical venous and arterial blood-gas values and acid-base status. At delivery (17.7 (3.2) min), mean maternal plasma concentrations of rapacuronium were 9041.4 (1259.1) ng ml-1 and 506.4 (24.9) ng ml-1 for Org 9488 (the main metabolite). Corresponding values for umbilical venous plasma were 808.0 (92.1) ng ml-1 and 59.1 (6.5) ng ml-1, and for umbilical arterial plasma, 361.4 (56.4) ng ml-1 and 29.7 (4.6) ng ml-1, respectively. Umbilical venous to maternal venous ratios for rapacuronium and Org 9488 were 8.8% (1.3)% and 10.2 (1.7)%, respectively.

Ropivacaine-induced seizure after extradural anaesthesia.

Ropivacaine is considered safer than bupivacaine, on the basis of experimental and human data that indicate a lower systemic toxicity. Here we report the occurrence of a single seizure after i.v. administration of ropivacaine 120 mg intended for extradural block in a patient having postpartum, tubal ligation. The only prodromal symptom was nervousness, and the only cardiovascular manifestation was sinus tachycardia. Systemic toxicity, although less than that expected with bupivacaine, can occur with ropivacaine.

Heparinase-guided thrombelastography in an anticoagulated parturient.

We describe the use of heparinase-guided thrombelastography in the assessment of a parturient who had been anticoagulated with heparin for suspected thromboembolic disease. Reversal of the heparin effect in the heparinase-treated sample facilitated administration of protamine and successful subarachnoid analgesia for delivery.

Fetal heart rate changes after intrathecal sufentanil or epidural bupivacaine for labor analgesia: incidence and clinical significance.

The objective of this study was to compare the incidence of intrapartum fetal heart tracing (FHT) abnormalities and the obstetric outcome after intrathecal sufentanil (ITS) versus epidural bupivacaine (EB). During the period from April to September 1994, 129 patients who met inclusion criteria were prospectively identified during labor at a single university-affiliated hospital. Inclusion criteria included: singleton, gestational age > or = 36 wk, and cephalic presentation. In the ITS group, epidural anesthesia was not administered before 60 min after ITS. Sixty-five consecutive ITS patients were compared to 64 consecutive EB patients. Each FHT was reviewed independently by two obstetricians blinded to the type of analgesia. The FHT characteristics evaluated included baseline rate, variability, and periodic changes. No differences in the incidence of clinically significant FHT abnormalities (recurrent late decelerations and/or bradycardia) were observed between the two groups (ITS 21.5% versus EB 23.4%). The rates of clinically significant FHT abnormalities in both groups was not different when patients with hypotension and medical complications were excluded (16.9% vs 17.1%). In addition, equal rates of hypotension (18.5% vs 17.2%) were noted between the groups. In both groups there was a significantly higher risk of cesarean section in patients whose previously normal FHT became abnormal postanalgesia when compared to patients without a new onset FHT abnormality (ITS 28.6% [4/14] versus 2.0% [1/51], P < 0.01; EB 33.3% [5/15] versus 8.2% [4/49], P < 0.05). This increased risk was associated with an increase in cesarean section for nonreassuring FHT in both groups (ITS 14.3% [2/14] versus 0% [0/51], P = 0.04; EB 13.3% [2/15] versus 0% [0/49], P = 0.05). These results support the conclusion that the incidence of clinically significant FHT abnormalities and hypotension is equivalent in patients receiving ITS when compared to EB within the first hour of administration. During this period, patients should have continuous FHT monitoring since a new onset FHT abnormality unveils and alerts the physicians to a possible compromised fetal condition and a corresponding increased risk of cesarean section.

Epinephrine improves the quality of spinal hyperbaric bupivacaine for cesarean section.

In a double-blind randomized study, the effects of the addition of epinephrine on hyperbaric spinal bupivacaine were studied in 63 patients having elective repeat cesarean sections. In the study group (32 patients), the addition of 0.2 mg epinephrine improved the quality of analgesia since fewer patients required supplementation of the spinal anesthetic; the motor block was more profound; and the times to two-segment regression, sensory recovery, and motor recovery were prolonged.