Department of Anaesthesiology and Critical Care, University College of Medical Sciences and Guru Teg Bahadur Hospital, Delhi, India.
Department of Obstetrics and Gynaecology, University College of Medical Sciences and Guru Teg Bahadur Hospital, Delhi, India.
J Anesth. 2022 Aug;36(4):456-463. doi: 10.1007/s00540-022-03067-2. Epub 2022 Apr 29.
Oxytocin infusions for uterine tone maintenance are recommended following initial low oxytocin doses during cesarean section. Very limited literature is available on the optimal infusion rates in laboring patients who have been earlier exposed to oxytocin.
105 patients, having received oxytocin for induction/augmentation of labor, received oxytocin infusions at rates of 2.5 IU/h (Group 2.5), 5 IU/h (Group 5) or 10 IU/h (Group 10) following 3 IU slow bolus. The primary outcome measure was estimated intraoperative blood loss; secondary outcome measures included uterine tone adequacy, requirements for additional uterotonics, and any side effects. Minor postpartum hemorrhage (PPH) was defined as blood loss > 500 ml and major/severe hemorrhage as blood loss > 1000 ml.
Group 10 had minimum blood loss (311.1 ± 44.9 ml) and uterotonic requirements compared to other groups (p < 0.001). Group 2.5 had maximum blood loss (549.4 ± 74.3 ml) and uterotonic requirements; Group 5 had intermediate values (402.0 ± 49.5 ml). Twenty-six patients in group 2.5 had minor PPH against only one in group 5 and none in group 10 (p < 0.001). No patient in either group had major PPH. The incidence of hypotension was higher in group 10 than in group 2.5 (p = 0.004). Nausea and vomiting were also more frequent in group 10 than in the other two groups.
Oxytocin infusions at 5 IU/h and 10 IU/h are more effective in reducing blood loss and preventing PPH than 2.5 IU/h. The dose of 10 IU/h, although the most efficacious, is associated with a high incidence of side effects. Hence, further studies are needed to find out the optimal maintenance infusion rate of oxytocin during cesarean section in laboring patients who have received oxytocin earlier.
剖宫产时，最初给予低剂量缩宫素后，建议使用缩宫素输注来维持子宫收缩。在先前接受过缩宫素的临产患者中，关于最佳输注率的文献非常有限。
105 名接受缩宫素引产/催产的患者，在给予 3IU 缓慢推注后，以 2.5IU/h（2.5 组）、5IU/h（5 组）或 10IU/h（10 组）的速度输注缩宫素。主要结局指标为估计术中失血量；次要结局指标包括子宫收缩情况、对额外宫缩剂的需求以及任何副作用。轻度产后出血（PPH）定义为出血量>500ml，重度/严重出血定义为出血量>1000ml。
与其他组相比，10 组的失血量（311.1±44.9ml）和宫缩剂需求最少（p<0.001）。2.5 组的失血量（549.4±74.3ml）和宫缩剂需求最大；5 组的失血量和宫缩剂需求处于中间值（402.0±49.5ml）。2.5 组有 26 例患者发生轻度 PPH，而 5 组只有 1 例，10 组无患者发生（p<0.001）。两组均无患者发生重度 PPH。10 组的低血压发生率高于 2.5 组（p=0.004）。10 组恶心和呕吐的发生率也高于其他两组。
与 2.5IU/h 相比，5IU/h 和 10IU/h 的缩宫素输注可更有效地减少出血量和预防 PPH。虽然 10IU/h 的剂量最有效，但副作用发生率较高。因此，需要进一步的研究来确定在先前接受过缩宫素的临产患者中，剖宫产时维持缩宫素输注的最佳维持输注率。
