Urmey W F, Grossi P, Sharrock N E, Stanton J, Gloeggler P J
Department of Anesthesiology, Hospital for Special Surgery, Cornell University, Medical College, New York, New York 10021, USA.
Anesth Analg. 1996 Aug;83(2):366-70. doi: 10.1097/00000539-199608000-00028.
The application of digital pressure above the injection site during interscalene block has been advocated to prevent cephalad spread of local anesthetic. In prior studies, radiographs taken immediately after interscalene injection of radiographic contrast have supported this concept. However, the clinical efficacy of digital pressure has not been previously tested. If digital pressure were effective in inhibiting cephalad spread of local anesthetic, attenuation of both hemidiaphragmatic paresis and the resulting compromise in pulmonary function would be expected. Sensory, motor, and pulmonary effects were prospectively evaluated in 20 patients presenting for elective shoulder surgery. Patients were randomly assigned to receive interscalene block with or without digital pressure. No clinical differences were seen between groups. All 20 patients had ipsilateral hemidiaphragmatic paresis by ultrasonographic evaluation and large mean decreases in forced vital capacity, 31.2% +/- 7.8% (with digital pressure), 33.7% +/- 12.8% (without digital pressure), and forced expiratory volume at one second, 27.9% +/- 9.3% (with digital pressure), 33.7 +/- 12.8% (without digital pressure). Peak sensory level of anesthesia to pinprick was not significantly different between groups, each group having mean levels of C-2 to C-3. Digital pressure was ineffective in limiting the flow of local anesthetic into the cervical plexus. Digital pressure influenced neither the incidence of diaphragmatic paresis nor the resulting large decreases in pulmonary function that result from interscalene block.
在肌间沟阻滞时，有人主张在注射部位上方施加指压以防止局部麻醉药向头侧扩散。在先前的研究中，肌间沟注射造影剂后立即拍摄的X线片支持了这一概念。然而，指压的临床疗效此前尚未得到测试。如果指压能有效抑制局部麻醉药向头侧扩散，预计双侧膈肌麻痹的程度以及由此导致的肺功能损害将会减轻。对20例择期肩部手术患者的感觉、运动和肺部影响进行了前瞻性评估。患者被随机分配接受有无指压的肌间沟阻滞。两组之间未观察到临床差异。通过超声评估，所有20例患者均有同侧膈肌麻痹，用力肺活量平均大幅下降，指压组为31.2%±7.8%，无指压组为33.7%±12.8%；一秒用力呼气量指压组为27.9%±9.3%，无指压组为33.7%±12.8%。两组对针刺的麻醉峰值感觉水平无显著差异，每组平均水平均为C-2至C-3。指压在限制局部麻醉药流入颈丛方面无效。指压既不影响膈肌麻痹的发生率，也不影响肌间沟阻滞导致的肺功能大幅下降。
