Efficacy of electrical stimulation on epidural anesthesia for cesarean section: a randomized controlled trial

Ultrasound-guided caudal anaesthesia combined with epidural anaesthesia for caesarean section: a randomized controlled clinical trial

BACKGROUND

Although epidural anaesthesia and spinal anaesthesia are currently the general choices for patients undergoing caesarean section, these two neuraxial anaesthesia methods still have drawbacks. Caudal anaesthesia has been considered to be more appropriate for gynaecological surgery. The purpose of this study was to compare epidural anaesthesia combined with caudal anaesthesia, spinal anaesthesia and single-space epidural anaesthesia for caesarean section with respect to postoperative comfort and intraoperative anaesthesia quality.

METHODS

In this clinical trial, 150 patients undergoing elective caesarean section were recruited and randomized into three groups according to a ratio of 1:1:1to receive epidural anaesthesia only, spinal anaesthesia only or epidural anaesthesia combined with caudal anaesthesia. The primary outcome was postoperative comfort in the three groups. Secondary outcomes included intraoperative anaesthesia quality and the incidences of nausea, vomiting, postdural puncture headache, maternal bradycardia, or hypotension.

RESULTS

More patients were satisfied with the intraoperative anaesthesia quality in the EAC group than in the EA group (P = 0.001). The obstetrician was more significantly satisfied with the intraoperative anaesthesia quality in the SA and EAC groups than in the EA group (P = 0.004 and 0.020, respectively). The parturients felt more comfortable after surgery in the EA and EAC groups (P = 0.007). The incidence of maternal hypotension during caesarean section was higher in the SA group than in the EA and EAC groups (P = 0.001 and 0.019, respectively).

CONCLUSIONS

Epidural anaesthesia combined with caudal anaesthesia may be a better choice for elective caesarean section. Compared with epidural anaesthesia and spinal anaesthesia, it has a higher quality of postoperative comfort and intraoperative anaesthesia.

Confirming identification of the epidural space: a systematic review of electric stimulation, pressure waveform analysis, and ultrasound and a meta-analysis of diagnostic accuracy in acute pain

To review the use of epidural electric stimulation test, pressure waveform analysis, and ultrasound assessment of injection as bedside methods for confirming identification of the epidural space in adults with acute pain, the PubMed database was searched for relevant reports between May and August 2022. Studies reporting diagnostic accuracy with conventional Touhy needles and epidural catheters were further selected for meta-analysis. Sensitivity and specificity were estimated using univariate logistic regression for electric stimulation and pressure analysis, and pooling of similar studies for ultrasound. Risk of bias and applicability was assessed using QUADAS-2. For electric stimulation, pressure waveform analysis, and ultrasound, respectively 35, 22, and 28 reports were included in the review and 9, 9, and 7 studies in the meta-analysis. Electric stimulation requires wire-reinforced catheters and an adequate nerve stimulator, does not reliably identify intravascular placement, and is affected by local anaesthetics. Sensitivity was 95% (95% CI 93-96%, N = 550) and specificity unknown (95% CI 33-94%, N = 44). Pressure waveform analysis is unaffected by local anaesthetics, but does not identify intravascular nor intrathecal catheters. Sensitivity was 90% (95% CI 72-97%, N = 694) and specificity 88% (95% CI 78-94%, N = 67). B-mode, M-mode and doppler ultrasound may be challenging, and data is still limited. Risk of bias was significant and accuracy estimates must be interpreted with caution. Electric stimulation and pressure waveform analysis seem clinically useful, although they must be interpreted cautiously. In the future, clinical trials in patients with difficult anatomy will likely be most useful. Ultrasound requires further investigation.