To explore the influence of dexmedetomidine combined with sufentanil on postoperative analgesia effect and immune function for patients undergoing lower limb fracture surgery.

One hundred cases patients of lower limb fracture undergoing open reduction and internal fixation of elective surgery in our hospital from January 2016 to November 2016 were selected (ASA Ⅰ-Ⅱ grade, male 51 cases and female 49 cases, 30-65 years old, 50-75 kg). All cases were randomly divided into sufentanil group (Group S) and dexmedetomidine combined with sufentanil group (Group DS) according to the random number table, who used patient-controlled intravenous analgesia (PCIA). The PCIA drug formulations of two groups were as followings: sufentanil group (Group S) used 3 μg/h sufentanil+ ondansetron 16 mg, dissolved in 0.9% sodium chloride injection 100 ml; dexmedetomidine combined with sufentanil group (Group DS) used dexmedetomidine 0.1 μg/(kg·h)+ sufentanil 2 μg/h+ ondansetron 16 mg, dissolved in 0.9% sodium chloride injection 100 ml; background infusion rate was 2 ml/h, and loading dose was 2 ml. Dose for patient-controlled analgesia (PCA) was 0.5 ml, and locking time was 15 min. The changes of pain, MAP, HR, sedation scores were recorded at 4 h (T₁), 8 h (T₂), 24 h (T₃) and 48 h (T₄) after operation; nausea and vomiting, hypotension, bradycardia, respiratory depression and other adverse reactions were aslo recorded at the same time. At 10 min before induction of anesthesia (T₀) and T₁-T₄ after operation, the CD₃₊, CD₄₊, CD₈₊ and NK cell activity of peripheral blood T lymphocyte subsets were determined using flow cytometry, and CD₄⁺/CD₈⁺ ratio was calculated.

The levels of MAP and HR in DS group at each time point after operation were lower than those in group S (P < 0.05), the level of visual analogue score (VAS) in DS group at different time points were significantly lower than those of s group: (1.8 ± 0.3) scores vs. (2.5 ± 0.5) scores, (1.1 ± 0.5) scores vs. (1.9 ± 0.3) scores, (1.0 ± 0.5) scores vs. (1.8 ± 0.5) scores, (0.8 ± 0.3) scores vs. (1.5 ± 0.6) scores (P < 0.05), Ramsay Sedation score was significantly higher than that of s group: (3.5 ± 0.3) scores vs. (2.4 ± 0.6) scores, (3.3 ± 0.5) scores vs. (2.5 ± 0.3) scores, (3.5 ± 0.6) scores vs. (2.3 ± 0.5) scores, (3.2 ± 0.4) scores vs. (2.2 ± 0.5)scores (P < 0.05); nausea and vomiting occurred in two patients after the operation of group DS, which was significantly lower than that of S group (P < 0.05); compared with those at T₀, CD₃₊, CD₄₊, CD₄₊/CD₈₊ and NK cells in the two groups of patients decreased significantly at the time of T₁-T₄ (P < 0.05); The levels of CD₃₊, CD₄₊, CD₄₊/CD₈₊ and NK cells were significantly higher in group DS at T₁-T₄ than those in group S(P < 0.05).

Dexmedetomidine combined with sufentanil for analgesia in patients with lower limb fracture surgery has better effect. It decreases the incidence of nausea and vomiting, and improves the cellular immune function of patients.

Bone; Analgesia; Immune; Dexmedetomidine; Sufentanil