Kongsgaard Ulf E, Høiseth Gudrun
Department of Anaesthesiology, Division of Emergencies and Critical Care, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0310 Oslo, Norway.
Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway.
Scand J Pain. 2019 Jul 26;19(3):465-471. doi: 10.1515/sjpain-2019-0032.
Background and aims Pupil size and reaction are influenced by opioids, an effect that is not considered to be affected by opioid tolerance. As clinicians have observed patients on high-dose opioids who exhibited seemingly normal pupil sizes, we wanted to dynamically assess the pupillary reflex in cancer patients on high-dose opioids. Methods We performed a dynamic assessment of the pupillary reflex in cancer patients on high-dose opioids and a control group of healthy volunteers using a portable, monocular, infrared pupillometer. We also performed a clinical examination and measured blood concentrations of opioids and their active metabolites. Results Sixty three patients who were on opioids for 2 months (median time) and on an oral morphine equivalent dose of 250 mg (median dose) were investigated. Most patients used more than one opioid. When correcting for age, pupil size in the group that had received no increase of opioid dose over the last 14 days was not significantly different from pupil size in the healthy volunteer group (p = 0.76), while the group that had increased the dose of opioids differed significantly from healthy volunteers (p = 0.006). We found no statistically significant correlation between total oral morphine equivalents and pupillary reactions or between blood opioid or opioid metabolite concentrations and baseline pupillary changes. Conclusion Pupillary changes do take place in patients on opioids. However, tolerance to these changes occurs when medication is not increased over time. Dynamic pupillometry can give additional information about the degree of tolerance to opioids. Implications These findings elucidate previous misconceptions regarding pupillary effects and tolerance to opioids.
瞳孔大小及反应受阿片类药物影响，且该效应被认为不受阿片类药物耐受性影响。由于临床医生观察到服用高剂量阿片类药物的患者瞳孔大小看似正常，我们希望动态评估服用高剂量阿片类药物的癌症患者的瞳孔反射。方法：我们使用便携式单眼红外瞳孔测量仪，对服用高剂量阿片类药物的癌症患者及健康志愿者对照组进行瞳孔反射的动态评估。我们还进行了临床检查，并测量了阿片类药物及其活性代谢物的血药浓度。结果：对63例服用阿片类药物2个月（中位时间）、口服吗啡等效剂量为250 mg（中位剂量）的患者进行了研究。大多数患者使用不止一种阿片类药物。在校正年龄后，过去14天内未增加阿片类药物剂量组的瞳孔大小与健康志愿者组的瞳孔大小无显著差异（p = 0.76），而增加了阿片类药物剂量的组与健康志愿者有显著差异（p = 0.006）。我们发现口服吗啡等效总量与瞳孔反应之间，或血阿片类药物或阿片类药物代谢物浓度与基线瞳孔变化之间无统计学显著相关性。结论：服用阿片类药物的患者会出现瞳孔变化。然而，当药物剂量未随时间增加时，会出现对这些变化的耐受性。动态瞳孔测量可提供有关阿片类药物耐受性程度的额外信息。意义：这些发现阐明了先前关于阿片类药物瞳孔效应和耐受性的误解。
