Department of Anesthesiology and Reanimation, University of Health Sciences, Bagcılar Training Research Hospital, İstanbul, Turkey.
Department of Molecular Biology and Genetics, Institute of Graduate Studies in Sciences, Istanbul University, İstanbul, Turkey.
Medicine (Baltimore). 2024 Oct 11;103(41):e40003. doi: 10.1097/MD.0000000000040003.
This prospective randomized study aimed to investigate the impact of needle types and diameters used in spinal anesthesia (SA) on optic nerve sheath diameter (ONSD) in patients undergoing lower extremity orthopedic surgery.
Patients were randomly assigned to 3 groups based on the needle type and size used for SA: Group 25w (25 gauge Whitacre needle), Group 27q (27 gauge Quincke needle), and Group 25q (25 gauge Quincke needle). Initially, 165 patients (55 in each group) were enrolled, with 146 patients ultimately included in the analysis (Group 25w, n = 49; Group 27q, n = 48; Group 25q, n = 49). ONSD measurements were conducted using ultrasound guidance at 5 time points: T0 (pre-SA), T1 (5 minutes post-SA), T2 (5 minutes post-tourniquet inflation), T3 (5 minutes post-tourniquet deflation), and T4 (24 hours post-operation). Additionally, oxygen saturation, systolic arterial pressure, mean arterial pressure, diastolic arterial pressure, and heart rate were recorded at these time points.
Analysis of ONSD measurements revealed no significant differences among the groups at time points T0,T1,T2, and T4 (P = .7293, P = .4428, P = .3676, and P = .3667, respectively). However, at T3, ONSD values were significantly higher in Group 27q compared to Group 25q (P = .0325). Across all groups, the mean ONSD values measured post-tourniquet release (T3) were higher than those at T0,T2, and T4 (P < .001 for all). The incidence of nausea was similar among the groups, and no cases of headache or visual impairment were reported within the initial 24 hours post-surgery.
In conclusion, our study suggests that while subarachnoid injection and tourniquet inflation do not impact intracranial pressure (ICP), tourniquet deflation leads to an increase in ICP during lower limb surgery under SA. Therefore, caution should be exercised when using a tourniquet in patients at risk of elevated ICP.
本前瞻性随机研究旨在探讨在进行下肢矫形外科手术的患者中，使用不同类型和直径的脊麻针对视神经鞘直径（ONSD）的影响。
根据脊麻针的类型和大小，患者被随机分为 3 组：25w 组（25 号 Whitacre 针）、27q 组（27 号 Quincke 针）和 25q 组（25 号 Quincke 针）。最初纳入 165 名患者（每组 55 名），最终有 146 名患者纳入分析（25w 组，n=49；27q 组，n=48；25q 组，n=49）。使用超声引导在 5 个时间点测量 ONSD：T0（脊麻前）、T1（脊麻后 5 分钟）、T2（止血带充气后 5 分钟）、T3（止血带放气后 5 分钟）和 T4（术后 24 小时）。同时，在这些时间点记录血氧饱和度、收缩压、平均动脉压、舒张压和心率。
对 ONSD 测量值的分析显示，在 T0、T1、T2 和 T4 时，各组之间没有显著差异（P=0.7293，P=0.4428，P=0.3676，P=0.3667，分别）。然而，在 T3 时，27q 组的 ONSD 值明显高于 25q 组（P=0.0325）。在所有组中，止血带释放后（T3）测量的平均 ONSD 值高于 T0、T2 和 T4（所有 P<0.001）。各组的恶心发生率相似，术后 24 小时内均无头痛或视力障碍报告。
总之，我们的研究表明，蛛网膜下腔注射和止血带充气不会影响颅内压（ICP），但止血带放气会导致下肢手术在脊麻下 ICP 升高。因此，在有 ICP 升高风险的患者中使用止血带时应谨慎。
