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].

我们怀着极大的兴趣阅读了 Wang 等人的文章 [1]。他们得出结论，不含阿片类药物的异丙酚麻醉减少了接受甲状腺和甲状旁腺手术的患者的术后恶心和呕吐 （PONV）。但是，我们对这项试验有几个担忧。

本研究的主要结果是 PONV 的发生率，定义为包括术后前 48 小时内恶心、干呕和呕吐率的复合结果。但是，在结果部分，没有单独记录恶心、干呕和呕吐的个别发生。这种复合结局可能导致高估干预对特定结局的影响。

将 PONV 严重程度作为次要结局的分析表明，术后前 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 未观察到统计学显着差异。对麻醉后监护病房和术后 24-48 小时 PONV 的分析显示，仅存在轻度的恶心和呕吐，两组之间无统计学意义。将复合结局分为轻度、中度和重度等简单类别，不利于对结果的精确分析。以前的研究开发了优化的评估量表来评估患者对 PONV 的主观体验，结果显示只有 1/5 的 PONV 患者表现出显着的临床相关性 [2， 3]。在本研究中，术后前 48 小时内共记录了 57 例 PONV，只有 20 例患者需要止吐药，只有 6 例报告症状严重。组间 PONV 的主要差异在轻度类别中观察到;然而，该队列可能经历了轻微的主观不适，并且可能未被归类为具有临床意义的 PONV。

完全无阿片类药物策略的实施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，气管拔管时间延长。完全避免使用阿片类药物并不会带来任何固有的优势，并且可能与不良反应和资源利用率增加有关 [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 毫克对 690 毫克）。相反，阿片类药物类药物麻醉组患者接受的舒芬太尼剂量高于标准剂量，使他们面临更大的术后阿片类药物相关不良副作用的风险 [5]。