Efficacy of ultrasound-guided versus body surface localization on scalp nerve block in awake craniotomy: report of 82 cases

Abstract

Objective To compare the efficacy of ultrasound-guided scalp nerve block (US-guided SNB) with that of body surface localization SNB in awake craniotomy (AC). Methods A retrospective cohort study was conducted to analyze the medical records of 82 patients with brain lesions who were treated in the Department of Neurosurgery, the First Affiliated Hospital of Chongqing Medical University and the Second Affiliated Hospital of Army Medical University from January 2016 to January 2022. The patients receiving US-guided SNB were included in the observation group (n=39, 19 males, averagely aged 50.51±16.49 years, body mass index of 22.10±3.66 kg/m2), and those receiving body surface localization SNB were enrolled in the control group (n=43, 24 males, averagely aged 48.02±16.44 years, body mass index of 22.98±3.55 kg/m2). The general information, operation-related indicators, and postoperative complications were compared between the 2 groups. Mean arterial pressure (MAP) and heart rate (HR) were recorded and analyzed at the time of admission (T0), skin incision (T1), awakening (T2), and 10 min (T3) and 20 min (T4) after awakening. Results In the observation group, the intraoperative wake-up time (6.53±1.84 min), number of body movements during the awake period (4.92±2.61 times/h), as well as dosages of nicardipine hydrochloride (0.97±0.27 mg), remifentanil (1.08±0.35 mg), dexmedetomidine hydrochloride (1.30±0.33 mg), and sufentanil citrate (22.42±2.63 ug) were significantly lower than those in the control group, with statistical significances (all P < 0.05). The HR of both groups showed a gradual upward trend at T1~T4, and the increase in the control group was much obvious with significance (F=35.978, P < 0.001). The MAP of the observation group was elevated at T1~T2 and then declined at T3~T4, while the MAP in the control group was increased during T1~T3 and decreased at T4, greatly higher than that in the observation group (F=43.286, P < 0.001). Conclusion US-guided SNB technique can improve the quality of AC surgery during awake period, reduce the intraoperative dose of general anesthetics, and stabilize hemodynamics.

Keywords

• ultrasound-guidance
• scalp nerve block
• awake craniotomy
• rain function lesions