Chang C L, Lin S S
Ma Zui Xue Za Zhi. 1989 Dec;27(4):335-40.
Forty-three ASA physical status I-II adult patients, receiving spinal anesthesia for lower abdominal or lower limb surgery, were allocated randomly to two groups. Group 1 patients (n = 21) were given heavy bupivacaine 12 mg and group 2 patients (n = 22) were given tetracaine 12 mg in 2.5 mL of 10% dextrose. Spinal anesthesia was performed in the lateral decubitus position the at L 3-4 interspace with a 25-G spinal needle. Radial artery blood samples were collected before and after spinal anesthesia fpr pH measurement using a NOVA Biomedical machine; CSF samples were collected before and after injection of local anesthetic, and local anesthetic was also collected at the same time, for pH measurement using a Radio pH meter. The time from injection to maximal cephalad spread of analgesia and level of spinal analgesia were measured by the pin-prick method. The result was regarded as a failure if pain sensation still existed at the level of the operation site after spinal anesthesia. There were 1 failure case in the bupivacaine group and 2 failures in tetracaine group. The pH of CSF and local anesthetic in these failures were compared with those in effective cases, and the results showed that there was no significant relationship between the pH value of CSF and the local anesthetic drug.
43例接受下腹部或下肢手术脊髓麻醉的ASA身体状况I-II级成年患者被随机分为两组。第1组患者（n = 21）给予重比重布比卡因12mg，第2组患者（n = 22）给予丁卡因12mg加于2.5mL 10%葡萄糖溶液中。脊髓麻醉在侧卧位L 3-4间隙用25G脊髓穿刺针进行。在脊髓麻醉前后采集桡动脉血样，使用诺瓦生物医学仪器测量pH值；在注射局部麻醉药前后采集脑脊液样本，同时也采集局部麻醉药，使用放射性pH计测量pH值。通过针刺法测量从注射到镇痛最大头端扩散的时间和脊髓镇痛水平。如果脊髓麻醉后手术部位仍有痛觉，则结果视为失败。布比卡因组有1例失败病例，丁卡因组有2例失败病例。将这些失败病例中脑脊液和局部麻醉药的pH值与有效病例中的进行比较，结果表明脑脊液的pH值与局部麻醉药之间无显著关系。
