Akinaga Chieko, Uchizaki Sakiko, Kurita Tadayoshi, Taniguchi Mizuki, Makino Hiroshi, Suzuki Akira, Uchida Toshiyuki, Suzuki Kazunao, Itoh Hiroaki, Tani Shigeki, Sato Shigehito, Terui Katsuo
Perinatal Medical Center, Hamamatsu University Hospital, Hamamatsu, Japan.
Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, Hamamatsu, Japan.
J Obstet Gynaecol Res. 2016 Apr;42(4):404-9. doi: 10.1111/jog.12926. Epub 2016 Jan 20.
Obstetricians sometimes administer intramyometrial oxytocin to stimulate uterine contraction during cesarean section, but its effects have not been well investigated. We performed a randomized, double-blind study to test the hypothesis that a small dose of intramyometrial oxytocin would induce acceptable uterine contractility more quickly and with fewer hemodynamic side-effects than the same dose administered intravenously.
Forty women with a single fetus at ≥36 weeks of gestational age scheduled for elective cesarean section under spinal anesthesia were randomized to the intravenous and intramyometrial groups to receive oxytocin at 0.07 IU/kg. The drug was administered immediately after umbilical cord clamping. Systolic blood pressure, heart rate, intraoperative blood loss, uterine tone, total amount of intraoperative oxytocin, and additional uterotonic drugs administered in the first 24 h were compared.
Maximum uterine contractility was achieved after 2 and 10 min for the intravenous and intramyometrial groups, respectively. The mean hemodynamic parameters of the intramyometrial group were stable. In contrast, the intravenous group showed a reduction in systolic blood pressure after 2-4 min and increased heart rate after 1-2 min. Intraoperative blood loss, total oxytocin dose, and frequency of additional uterotonic drugs were comparable between the two groups.
Although intraoperative blood loss was comparable, a small dose of intramyometrial oxytocin was inappropriate to obtain a prompt and acceptable uterine contraction during cesarean section.
产科医生有时在剖宫产术中给予肌层内注射缩宫素以刺激子宫收缩，但其效果尚未得到充分研究。我们进行了一项随机双盲研究，以检验以下假设：与静脉注射相同剂量的缩宫素相比，小剂量的肌层内注射缩宫素能更快地诱导出可接受的子宫收缩力，且血流动力学副作用更少。
40例孕龄≥36周、单胎、计划在脊髓麻醉下行择期剖宫产的妇女被随机分为静脉注射组和肌层内注射组，均接受0.07 IU/kg的缩宫素。药物在脐带结扎后立即给药。比较两组的收缩压、心率、术中出血量、子宫张力、术中缩宫素总量以及术后24小时内额外使用的宫缩剂。
静脉注射组和肌层内注射组分别在2分钟和10分钟后达到最大子宫收缩力。肌层内注射组的平均血流动力学参数稳定。相比之下，静脉注射组在2 - 4分钟后收缩压降低，1 - 2分钟后心率升高。两组的术中出血量、缩宫素总剂量和额外使用宫缩剂的频率相当。
虽然术中出血量相当，但在剖宫产术中，小剂量的肌层内注射缩宫素并不适合迅速获得可接受的子宫收缩。
