Effect of 16-gauge needle as needle-over-needle guidance introducer in single-operator real-time ultrasound-guided spinal anesthesia: a randomized controlled trial.

PURPOSE: We aimed to evaluate the effect of a 16-gauge needle as an introducer in single-operator real-time ultrasound-guided subarachnoid anesthesia.

METHODS

One hundred and two parturients undergoing cesarean section were randomized to undergo real-time ultrasound-guided subarachnoid anesthesia either with (group T) or without (group C) a 16-gauge needle as an introducer. The primary outcome was the number of needle passes required for a successful dural puncture. Secondary outcomes included the number of attempts, first pass/attempt success rate, procedure time, parturients’ pain, puncture depth, periprocedural complications, and the quality of sonographic images.

RESULTS

The median number of needle passes and attempts were significantly lower in group T than in group C [1 (1–2) vs. 2 (1–3), median difference (95% CI): 1 (0–1), P < 0.001; 1 (1–1) vs. 1 (1–1), median difference (95% CI): 0 (0–0), P = 0.042]. The first pass/attempt success rates in group T were significantly higher than in group C (70.6% vs. 35.3%, 100% vs. 88.2%; both, P < 0.001). The total procedural time was shorter in group T [108 (94–130) vs. 123 (100–163) seconds, median difference (95% CI): 15 (3–33), P < 0.016]. No intergroup differences of pain, puncture depth, periprocedural complications and quality of sonographic images were seen.

CONCLUSIONS

The application of a 16-gauge needle as an introducer showed improved efficacy in terms of the number of needle passes/attempts, first pass/attempt success rates, and procedural time in real-time ultrasound-guided subarachnoid anesthesia. TRIAL REGISTRATION: The study was registered in the Chinese Clinical Trial Registry (registration date February 27, 2023 registration number ChiCTR2300068702).