We read with great interest the article by Wang et al. [1]. They concluded that opioid-free propofol anaesthesia reduced postoperative nausea and vomiting (PONV) in patients undergoing thyroid and parathyroid surgery. However, we have several concerns about this trial.

The primary outcome of this study was the incidence of PONV, defined as a composite outcome that encompasses the rates of nausea, retching and vomiting within the first 48 h postoperatively. However, in the results section, the individual occurrences of nausea, retching and vomiting are not documented separately. This composite outcome may lead to an overestimation of the impact of the intervention on specific outcomes.

The analysis of the severity of PONV as a secondary outcome indicates that significant differences in PONV rates within the first 24 h postoperatively are limited to mild symptoms, with no statistically significant differences observed for moderate or severe PONV after adjustment. The analyses for both the post-anaesthesia care unit and the 24–48 h postoperative PONV show that only mild levels of nausea and vomiting were present, with no statistical significance between the two groups. The classification of the composite outcome into simple categories of mild, moderate and severe does not facilitate precise analyses of the results. Previous studies have developed optimised assessment scales to evaluate patients' subjective experiences of PONV, revealing that only 1 in 5 patients with PONV display significant clinical relevance [2, 3]. In the present study, a total of 57 instances of PONV were recorded in the first 48 h postoperatively, with only 20 patients requiring anti-emetics and just six reporting severe symptoms. The primary differences in PONV between groups were noted in the mild category; however, this cohort likely experienced minimal subjective discomfort and may not be classified as having clinically significant PONV.

The implementation of a completely opioid-free strategy necessitates a significant increase in the doses of alternative intra-operative medications, such as ketamine or dexmedetomidine, potentially leading to more adverse effects. In this study, patients allocated to the opioid-free group experienced an increased incidence of nightmares or hallucinations and extended tracheal extubation times. Completely avoiding opioids does not convey any inherent advantages and may be associated with adverse effects and increased resource utilisation [4]. For instance, the anaesthesia protocol for the opioid-free group appears to have utilised a greater amount of propofol (740 mg vs. 690 mg). Conversely, patients in the opioid-inclusive anaesthesia group received higher than standard doses of sufentanil, placing them at a greater risk for postoperative opioid-related adverse side effects [5].

我们饶有兴趣地阅读了王等人的文章。 [ 1 ]。他们得出的结论是，不含阿片类药物的丙泊酚麻醉可减少接受甲状腺和甲状旁腺手术的患者术后恶心和呕吐（PONV）。然而，我们对这次试验有几个担忧。

本研究的主要结果是 PONV 的发生率，其定义为综合结果，包括术后 48 小时内恶心、干呕和呕吐的发生率。然而，在结果部分，恶心、干呕和呕吐的个别发生没有单独记录。这种综合结果可能会导致高估干预措施对特定结果的影响。

作为次要结果对 PONV 严重程度的分析表明，术后 24 小时内 PONV 发生率的显着差异仅限于轻度症状，调整后中度或重度 PONV 没有观察到统计学上的显着差异。对麻醉后监护室和术后 24-48 小时 PONV 的分析表明，仅出现轻度恶心和呕吐，两组之间没有统计学意义。将综合结果简单地分为轻度、中度和重度类别不利于对结果进行精确分析。先前的研究已经开发出优化的评估量表来评估患者对 PONV 的主观体验，表明只有五分之一的 PONV 患者表现出显着的临床相关性 [ 2, 3 ]。在本研究中，术后 48 小时内总共记录了 57 例 PONV，其中只有 20 例患者需要止吐，只有 6 例报告有严重症状。组间 PONV 的主要差异在于轻度类别；然而，该队列可能经历了轻微的主观不适，可能不会被归类为具有临床意义的 PONV。

实施完全不含阿片类药物的策略需要显着增加替代术中药物的剂量，例如氯胺酮或右美托咪定，这可能会导致更多的不良反应。在这项研究中，分配到无阿片类药物组的患者噩梦或幻觉的发生率增加，并且气管拔管时间延长。完全避免使用阿片类药物并不具有任何固有的优势，并且可能会带来不利影响和增加资源利用率[ 4 ]。例如，无阿片类药物组的麻醉方案似乎使用了更多的异丙酚（740 毫克与 690 毫克）。相反，阿片类药物麻醉组的患者接受高于标准剂量的舒芬太尼，使他们面临术后阿片类药物相关不良副作用的更大风险[ 5 ]。