不同镇痛方法对高血压病人上腹部手术后血浆内皮素及心钠素的影响

Effect of different methods of postoperative pain management on plasma endothelin and atrial natriuretic polypeptide in patients with hypertension undergoing upper abdominal surgery

目的观察不同镇痛方法对上腹部手术合并高血压病患者血浆内皮素(ET)及心钠素(ANP)的影响。方法30例拟行上腹部手术的高血压患者根据不同镇痛方式随机分为三组:A组为对照组,术后根据需要间断肌注哌替啶镇痛;B组术后行硬膜外自控镇痛(PCEA);C组术后行静脉自控镇痛(PCIA)。采用放免法测定术前、术毕、术后24 h、术后48 h血浆ET及ANP浓度;监测HR、BP及进行VAS评分。结果 B组及C组术后24 h ET及ANP值显著低于A组(P<0.05),且B组降低幅度更大(P<0.01),持续时间更长,至术后48 h B组仍低于A组(P<0.05),而C组与A组比较差异无显著性。B及C组术后HR、SBP、DBP及VAS评分显著低于同期A(P<0.05),且B组数值更低(P<0.01)。结论术后镇痛能有效减轻上腹部手术病人疼痛、改善循环功能、降低高血压病患者上腹部手术后ET及ANP值,减少术后并发症,有利于病人恢复,且PCEA效果更优。

Objective To investigate the effect of different methods of postoperative pain management on plasma endothelin(ET) and atrial natriuretic polypeptide( ANP) in patients with hypertension after upper abdominal surgery.Methods Thirty patients with hypertension (19 male, 11 female) aged 48-75 years, weighing 49-73 kg undergoing upper abdominal surgery were enrolled in the study. The diagnosis of hypertension was based on the criteria established by WHO/ISH (systolic≥ 140 mm Hg or diastolic ≥ 90 mm Hg) .The patients were randomly divided into three groups of 10 patients each according to the methods of postoperative pain management: control group(A); PCEAgroup(B) and PCIA group(C). In group A patients received a bolus of pethidine 50 mg im when patients complained that pain was intolerable. In group B an epidural catheter was placed at T8-9 before induction of general anesthesia. After operation patients received a loading dose of morphine 2 mg, droperidol 2.5 mg and 0.375% bupivacaine 6 ml through the epidural catheter, followed by patient-controlled epidural analgesia(PCEA) with a mixture of fentanyl 400 μg + droperidol 2.5 mg + bupivacaine 150 mg in 100 ml (background infusion 2 ml ·h-1,bolus dose 1 ml, lock-out interval 5 min ). In group C patients received a loading dose of morphine 2 mg and droperidol 2.5 mg followed by patient-controlled intravenous analgesia (PCIA) with a mixture of morphine 10 mg + fentanyl 500 μg + droperidol 2.5 mg in 100 ml ( background infusion 2 ml·h-1, bolus dose 1 ml, lock-out interval 5 min). PCEA and PCIA lasted for 48 h. Operation was performed under general anesthesia induced with midazolam 5 mg, fentanyl 3 μg·kg-1 ,propofol 1.5 mg·kg-1 and vecuronium 0.15 μg· kg-1 and maintained with isoflurane inhalation and vecuronium infusion(0.3 mg· kg-1· h-1 ) .Venous blood samples were obtained before operation(T1 ) ,at the end of operation(T2) ,24 h(T3) and 48 h after operation(T4) for determination of plasma ET and ANP. Pain was assessed using visual analog scale(VAS) .Results Plasma ET and ANP in group B and C were significantly lower than those in group A 24 h after operation( P < 0.05 for group C; P < 0.01 for group B) . Forty-eight hours after operation (T4 ) plasma ET and ANP were still significantly lower in group B than those in group A ( P < 0.05) ,but there was no significant difference in plasma ET and ANP between group A and C( P > 0.05). BP, HR and VAS scores were higher in group A than those in group B and C after operation. Conclusions In patients with hypertension both PCEA and PCIA can effectively relieve pain after upper abdominal operation and suppress the increase in plasma ET and ANP level after operation. PCEA is more effective than PCIA.