Preprocedural ultrasound assessment does not improve trainee performance of spinal anesthesia for obstetrical patients: a randomized controlled trial.

STUDY OBJECTIVE: This randomized controlled trial was designed to evaluate the efficacy of additional information from preprocedure ultrasound examination to aid anesthesiology trainees performing spinal anesthesia for obstetric patients. DESIGN: Trainee residents were randomly allocated to landmark technique and anatomy demonstration via ultrasound examination or landmark technique only for spinal anesthetic placement. SETTING: Obstetric delivery suite. PATIENTS: Eighty healthy obstetric patients undergoing elective cesarean delivery. INTERVENTION: Ultrasound examination prior to spinal anesthetic placement. MEASUREMENTS: The primary outcome was the number of attempts for the spinal anesthetic. Secondary outcomes included placement duration; block height; and the incidence of need for staff intervention, paresthesia, and bloody tap. Subjective ease of placement was rated on a 100-mm visual analog scale. MAIN RESULTS: Baseline demographic data were similar between the patient groups. The median number of attempts with preprocedure ultrasound and landmark was 3 (interquartile range, 2-7). This was not significantly different from the number of attempts with landmark technique only of 3 (1-60) (P=.69). The median duration of spinal placement with ultrasound and landmark was 92 (51-140) seconds vs 75 (53-126) seconds with landmark only (P=.57). There was no statistical difference between the groups in spinal placement duration, need for staff intervention, paresthesia, bloody tap, lumbar interspace, or block height. There was no difference in subjective ease of spinal placement by the resident. CONCLUSIONS: In this study of junior anesthesia trainees performing obstetrical spinal anesthesia with preprocedure ultrasound and landmark technique or landmark technique only, no significant difference was observed in the number of attempts, duration of spinal placement, subjective ease of spinal placement, or any other measured secondary outcome.

The efficacy of 2 doses of epidural morphine for postcesarean delivery analgesia: a randomized noninferiority trial.

BACKGROUND: A single dose of epidural morphine is effective in reducing pain after cesarean delivery but is associated with adverse effects. In this study, we sought to establish whether half the traditional dose of epidural morphine, when administered as part of a multimodal analgesia regimen after cesarean delivery, was associated with noninferior analgesia and fewer adverse effects. METHODS: Ninety term parturients undergoing cesarean delivery under epidural anesthesia were enrolled in this randomized, double-blinded, noninferiority study. Patients were randomly allocated to receive either 3 mg epidural morphine or, half this dose, 1.5 mg epidural morphine. In addition, subjects received regular systemic ketorolac and acetaminophen. Rescue analgesia (oral oxycodone) was administered for breakthrough pain. The primary outcome was the difference between groups in total opioid consumption (measured in median IV morphine equivalents) within the first 24 hours. A prespecified noninferiority margin of 3.33 mg was used. Secondary outcomes included total opioid consumption from 24 to 48 hours, numerical rating scale pain scores, time to first request for analgesics, overall pain relief, maternal satisfaction, quality of recovery, and adverse effects. RESULTS: Data were analyzed for 87 participants. Noninferiority was demonstrated as the difference in median 24-hour opioid consumption between the 1.5 mg epidural morphine (EM) and 3 mg EM groups was 0 mg (1-sided 95% confidence interval [CI], 2.5 mg), which was less than the prespecified noninferiority margin of 3.33 mg. No significant differences were found between groups in the median 24- to 48-hour opioid consumption or the median total opioid consumption within 48 hours. Pain scores, overall pain relief, and satisfaction at 24 and 48 hours were not significantly different between groups. The 1.5 mg EM group had a lower incidence of moderate and severe pruritus at 6 and 12 hours (relative risk [RR] 0.44, 95% CI, 0.2-0.9 and RR 0.41, 95% CI, 0.2-0.8, respectively) and had less nausea and vomiting at 6 hours (RR 0.22, 95% CI, 0.05-0.9). There was no difference in average pain scores at 12 weeks between the 2 groups. CONCLUSION: When used as part of a multimodal analgesia regimen, 1.5 mg epidural morphine provided noninferior postcesarean analgesia and caused fewer adverse effects compared with 3 mg epidural morphine.

A new helper phage and phagemid vector system improves viral display of antibody Fab fragments and avoids propagation of insert-less virions.

Phage display technology (PDT) is a powerful method for isolating functional gene products such as antigen-specific monoclonal antibodies (mAbs). To improve the effectiveness of PDT, we sought to optimize display of Fab-g3p (antibody fragment fused with viral gene 3 protein) on phagemid virions and to optimize the yield of such phage. To do so, we constructed a novel helper phage, Phaberge, having a conditional deficiency in g3p production. Unlike most other published g3p-deficient helper phage, Phaberge is produced at high levels, 10(11) PFU/ml. As compared to g3p-sufficient helper phage, Phaberge caused a 5-20-fold increase in display level. Another novel feature is that Phaberge only packages insert-containing, not insert-less, phagemid into infectious virions. This should prove useful in preserving quality of phagemid libraries during propagation. In addition, other parameters were also found to affect production of phagemid virions. In particular, the choice of bacterial host cell, phagemid construct and growth temperature had a substantial impact on display levels, but generally no effect on number of phagemid virions produced. In short, we have established a set of parameters that improve production and quality of phagemid virions which we expect to facilitate the isolation of mAbs or other gene products by PDT.