ABSTRACT
BACKGROUND: Nalbuphine has been suggested to be used for post-cesarean section (CS) intravenous analgesia. However, ideal concentration of nalbuphine for such analgesia remains unclear. The present study was conducted to explore an ideal concentration of nalbuphine for post-CS intravenous analgesia by evaluating the analgesic effects and side-effects of three different concentrations of nalbuphine combined with hydromorphone for post-CS intravenous analgesia in healthy parturients. METHODS: One-hundred-and-fourteen parturients undergoing elective CS were randomly allocated to one of three groups (38 subjects per group) according to an Excel-generated random number sheet to receive hydromorphone 0.05 mg/mL + nalbuphine 0.5 mg/mL (group LN), hydromorphone 0.05 mg/mL + nalbuphine 0.7 mg/mL (group MN), and hydromorphone 0.05 mg/mL + nalbuphine 0.9 mg/mL (group HN) using patient-controlled analgesia (PCA) pump. Visual analog scale (VAS) for pain, PCA bolus demands, cumulative PCA dose, satisfaction score, Ramsay score, and side-effects such as urinary retention were recorded. RESULTS: The number of PCA bolus demands and cumulative PCA dose during the first 48âh after CS were significantly higher in group LN (21â±â16 bolus, 129â±â25âmL) than those in group MN (15â±â10 bolus, 120â±â16âmL) (both Pâ<â0.05) and group HN (13â±â9 bolus, 117â±â13âmL) (both Pâ<â0.01), but no difference was found between group HN and group MN (both Pâ>â0.05). VAS scores were significantly lower in group HN than those in group MN and group LN for uterine cramping pain at rest and after breast-feeding within 12 h after CS (all Pâ<â0.01) and VAS scores were significantly higher in group LN than those in group MN and group HN when oxytocin was intravenously infused within 3 days after CS (all Pâ<â0.05), whereas VAS scores were not statistically different among groups for incisional pain (all Pâ>â0.05). Ramsay sedation scale score in group HN was significantly higher than that in group MN at 8 and 12 h after CS (all Pâ<â0.01) and group LN at 4, 8, 12, 24 h after CS (all Pâ<â0.05). CONCLUSIONS: Hydromorphone 0.05âmg/mLâ+ânalbuphine 0.7âmg/mL for intravenous PCA could effectively improve the incisional pain and uterine cramping pain management and improve comfort in patients after CS. TRIAL REGISTRATION NUMBER: ChiCTR1800015014, http://www.chictr.org.cn/ Chinese Clinical Trial Registry.