Effects of dexmedetomidine in combination with fentanyl-based intravenous patient-controlled analgesia on pain attenuation after open gastrectomy in comparison with conventional thoracic epidural and fentanyl-based intravenous patient-controlled analgesia

Abstract

Background: This study was investigated the effects of dexmedetomidine in combination with fentanyl-based intravenous patient-controlled analgesia (IV-PCA) on pain attenuation in patients undergoing open gastrectomy in comparison with conventional thoracic epidural patient-controlled analgesia (E-PCA) and IV-PCA. Methods: One hundred seventy-one patients who planned open gastrectomy were randomly distributed into one of the 3 groups: conventional thoracic E-PCA (E-PCA group, n = 57), dexmedetomidine in combination with fentanyl-based IV-PCA (dIV-PCA group, n = 57), or fentanyl-based IV-PCA only (IV-PCA group, n = 57). The primary outcome was the postoperative pain intensity (numerical rating scale) at 3 hours after surgery, and the secondary outcomes were the number of bolus deliveries and bolus attempts, and the number of patients who required additional rescue analgesics. Mean blood pressure, heart rate, and adverse effects were evaluated as well. Results: One hundred fifty-three patients were finally completed the study. The postoperative pain intensity was significantly lower in the dIV-PCA and E-PCA groups than in the IV-PCA group, but comparable between the dIV-PCA group and the E-PCA group. Patients in the dIV-PCA and E-PCA groups needed significantly fewer additional analgesic rescues between 6 and 24 hours after surgery, and had a significantly lower number of bolus attempts and bolus deliveries during the first 24 hours after surgery than those in the IV-PCA group. Conclusions: Dexmedetomidine in combination with fentanyl-based IV-PCA significantly improved postoperative analgesia in patients undergoing open gastrectomy without hemodynamic instability, which was comparable to thoracic E-PCA. Furthermore, this approach could be clinically more meaningful owing to its noninvasive nature.

Keywords: dexmedetomidine; epidural; fentanyl; intravenous; patient-controlled analgesia; postoperative pain..

Figure 1

Consort flow diagram. E-PCA, epidural patient-controlled analgesia; dIV-PCA, dexmedetomidine in combination with fentanyl-based intravenous patient-controlled analgesia; IV-PCA, intravenous patient-controlled analgesia; SBP, systolic blood pressure; PONV, postoperative nausea and vomiting.

Figure 2

Pain score at rest during the first 36 h after surgery. Data are expressed as mean ± standard deviation. ^†P < 0.001, ^††P < 0.01 vs. the IV-PCA group (Bonferroni corrected); *P < 0.001, **P < 0.01 vs. the IV-PCA group (Bonferroni corrected). E-PCA, epidural patient-controlled analgesia; dIV-PCA, dexmedetomidine in combination with fentanyl-based intravenous patient-controlled analgesia; IV-PCA, intravenous patient-controlled analgesia; NRS, numerical rating scale.

Figure 3

Number of bolus deliveries (A) and the number of bolus attempts (B) during the first 36 h after surgery. Data are expressed as mean ± standard deviation. ^†P < 0.01, ^††P < 0.05 vs. the IV-PCA group (Bonferroni corrected); *P < 0.01, **P < 0.05 vs. the IV-PCA group (Bonferroni corrected). E-PCA, epidural patient-controlled analgesia; dIV-PCA, dexmedetomidine in combination with fentanyl-based intravenous patient-controlled analgesia; IV-PCA, intravenous patient-controlled analgesia

Figure 4

Mean blood pressure (A) and heart rate (B) from prior induction until 36 h after surgery. Data are expressed as mean ± standard deviation. *P < 0.05, ^†P < 0.05 vs. the IV-PCA group (Bonferroni corrected); ^‡P < 0.05 vs. the E-PCA group (Bonferroni corrected). E-PCA, epidural patient-controlled analgesia; dIV-PCA, dexmedetomidine in combination with fentanyl-based intravenous patient-controlled analgesia; IV-PCA, intravenous patient-controlled analgesia; Baseline, before induction of anesthesia; PACU, on arrival of post-anesthetic care unit.