A Large-Scale Study Assessing Gender Differences in Postoperative Patient-Controlled Analgesia in Chinese Population

Abstract

The effects of gender differences on postoperative pain control and analgesic consumption are inconclusive although current studies suggest that women report more pain than men in severity, frequency and duration. This study aims to study the gender differences in postoperative pain relief and morphine consumption using patient-controlled analgesia (PCA) in a single institution between years of 2002 and 2007. Common side effects of PCA morphine use and satisfaction of patients for postoperative pain control between the genders were also assessed. More than 7000 patients were evaluated. The overall pain scores of females were significantly higher from postoperative day 1 to day 3 (all p<0.05). However, total morphine consumption was higher for males than females (12.6 µg/kg/h vs. 10.7µg/kg/h respectively, p<0.01). A substantial proportion of female patients experienced common side effects such as nausea, vomiting and dizziness (all p<0.01) despite they used less morphine. More male patients ranked PCA for pain relief as good than females (82.1% vs. 79.3%, p<0.003). We conclude that, in our Chinese population, females had significantly higher postoperative pain scores but used less PCA morphine. They also experienced more common side effects of opioids with low satisfaction in pain relief when using postoperative PCA. Our large-scale study provides further insight into the postoperative pain control behavior between genders of Chinese patients.