美国克利夫兰诊所Daniel I. Sessler团队研究了腹部手术后静脉注射对乙酰氨基酚对术后低氧血症的影响。相关论文于2020年7月28日发表在《美国医学会杂志》上。

阿片类药物引起的通气抑制和低氧血症在术后患者中很常见、很严重，且常被忽略。非阿片类镇痛药可减少阿片类药物的使用，在一定程度上有可能减少术后低氧血症。

为了确定静脉注射对乙酰氨基酚与安慰剂相比，是否会缩短患者的低氧血症持续时间，2015年2月至2018年10月，研究组在美国的两家学术型医院进行了一项随机、安慰剂对照、双盲试验，共招募了580例接受腹部手术的患者，平均年龄为49岁，女性占48%。将其随机分组，289例在手术开始后接受静脉注射对乙酰氨基酚，291例接受静脉注射生理盐水安慰剂，每6小时重复一次，直到术后48小时或出院。并随访至2019年2月。

共有570例患者完成了试验。对乙酰氨基酚组中血氧饱和度（SpO₂）低于90%的中位持续时间为每小时0.7分钟，安慰剂组为每小时1.1分钟。两组间的8个次要指标均无显著差异。对乙酰氨基酚组术后48小时的平均疼痛评分为4.2分，安慰剂组为4.4分。对乙酰氨基酚组的阿片类药物使用量为50mg吗啡当量，安慰剂组为58mg吗啡当量，几何平均比为0.86。

总之，在接受腹部手术的患者中，与安慰剂相比，术后静脉注射乙酰氨基酚并未显著减少术后48小时内低氧血症的持续时间。

附：英文原文

Title: Effect of Intravenous Acetaminophen on Postoperative Hypoxemia After Abdominal Surgery: The FACTOR Randomized Clinical Trial

Author: Alparslan Turan, Hani Essber, Wael Saasouh, Karen Hovsepyan, Natalya Makarova, Sabry Ayad, Barak Cohen, Kurt Ruetzler, Loran Mounir Soliman, Kamal Maheshwari, Dongsheng Yang, Edward J. Mascha, Wael Ali Sakr Esa, Herman Kessler, Conor P. Delaney, Daniel I. Sessler

Issue&Volume: 2020/07/28

Abstract: Importance  Opioid-induced ventilatory depression and hypoxemia is common, severe, and often unrecognized in postoperative patients. To the extent that nonopioid analgesics reduce opioid consumption, they may decrease postoperative hypoxemia.

Objective  To test the hypothesis that duration of hypoxemia is less in patients given intravenous acetaminophen than those given placebo.

Design, Setting, and Participants  Randomized, placebo-controlled, double-blind trial conducted at 2 US academic hospitals among 570 patients who were undergoing abdominal surgery, enrolled from February 2015 through October 2018 and followed up until February 2019.

Interventions  Participants were randomized to receive either intravenous acetaminophen, 1 g (n=289), or normal saline placebo (n=291) starting at the beginning of surgery and repeated every 6 hours until 48 postoperative hours or hospital discharge, whichever occurred first.

Main Outcomes and Measures  The primary outcome was the total duration of hypoxemia (hemoglobin oxygen saturation [Spo2] <90%) per hour, with oxygen saturation measured continuously for 48 postoperative hours. Secondary outcomes were postoperative opioid consumption, pain (0- 10-point scale; 0: no pain; 10: the most pain imaginable), nausea and vomiting, sedation, minimal alveolar concentration of volatile anesthetic, fatigue, active time, and respiratory function.

Results  Among 580 patients randomized (mean age, 49 years; 48% women), 570 (98%) completed the trial. The primary outcome, median duration with Spo2 of less than 90%, was 0.7 (interquartile range [IQR], 0.1-5.1) minutes per hour among patients in the acetaminophen group and 1.1 (IQR, 0.1-6.6) minutes per hour among patients in the placebo group (P=.29), with an estimated median difference of 0.04 (95% CI,0.18 to 0.11) minutes per hour. None of the 8 secondary end points differed significantly between the acetaminophen and placebo groups. Mean pain scores within initial 48 postoperative hours were 4.2 (SD, 1.8) in the acetaminophen group and 4.4 (SD, 1.8) in the placebo group (difference, 0.28; 95% CI, –0.71 to 0.15); median opioid use in morphine equivalents was 50 mg (IQR, 18-122 mg) and 58 mg (IQR, 24-151 mg) , respectively, with a ratio of geometric means of 0.86 (95% CI, 0.61-1.21).

Conclusions and Relevance  Among patients who underwent abdominal surgery, use of postoperative intravenous acetaminophen, compared with placebo, did not significantly reduce the duration of postoperative hypoxemia over 48 hours. The study findings do not support the use of intravenous acetaminophen for this purpose.

DOI: 10.1001/jama.2020.10009

Source: https://jamanetwork.com/journals/jama/article-abstract/2768808