Postoperative analgesia and recovery course after major colorectal surgery in elderly patients: a randomized comparison between intrathecal morphine and intravenous PCA morphine.

BACKGROUND AND OBJECTIVES: Intrathecal morphine is a widely used method for postoperative pain relief after major abdominal surgery. The aim of this randomized, double-blinded study was to compare intrathecal morphine and intravenous PCA morphine for postoperative analgesia and recovery course after major colorectal surgery in elderly patients. METHODS: After written informed consent, patients >70 years of age were prospectively and randomly assigned to receive either preoperative intrathecal morphine (0.3 mg) and postoperative patient-controlled (PCA) intravenous morphine (IT morphine) or PCA alone (group control). Results are presented as mean +/- SD (95% confidence interval). RESULTS: Twenty-six patients successfully completed the study in each group. In the IT morphine group, rate of awakening was delayed. Pain intensity and daily intravenous morphine consumption were significantly reduced 1 and 2 days after surgery in the IT morphine group (P < .01). Mental function (assessed by Mini Mental State and Digit Symbol Substitution Test) was similar in both groups. Episodes of postoperative delirium/confusion occurred similarly in both groups. Time to ileus resolution and time to ambulation without assistance did not differ between the 2 groups. The duration of hospitalization was 8.4 +/- 1.7 (7-11) days and 7.9 +/- 2.0 (6-9.9) days for control and IT morphine, respectively (nonstatistical difference). Patients in the IT morphine group had longer time to awakening from anesthesia and experienced more sedation. CONCLUSIONS: Intrathecal morphine, as compared with intravenous PCA morphine alone, improves immediate postoperative pain and reduces parenteral morphine consumption but does not improve postoperative recovery in elderly patients after major colorectal surgery.

Environmental and genetic factors associated with morphine response in the postoperative period.

OBJECTIVE: The aim of this study was to investigate the respective influence of genetic and nongenetic factors on morphine dose requirements and adverse effects after colorectal surgery. METHODS: Seventy-four patients who planned to undergo colorectal surgery were included in this pilot study. The cumulative 24-hour postoperative dose of morphine and postoperative nausea or vomiting requiring the antiemetic ondansetron were the 2 clinical end points. The association of patient characteristics, A118G mu-opioid receptor (OPRM1) single-nucleotide polymorphism (SNP); T802C uridine diphosphate-glucuronosyltransferase 2B7 (UGT2B7) SNP; and 2 adenosine triphosphate-binding cassette, subfamily B, member 1 (ABCB1) (multidrug resistance 1 [MDR1]) exonic SNPs (G2677T/A and C3435T) with study end points was investigated. RESULTS: Age, creatinine clearance, and the regular use of psychotropic agents were found to be significantly associated with postoperative morphine dose requirements by univariate analysis. Multivariate analysis identified that age (P = .01) and the use of psychotropic agents before surgery (P = .03) were positively associated with a higher rate of morphine consumption. A higher weight (P = .05) and the ABCB1 homozygous GG-CC diplotype (P = .03) were significantly associated with fewer morphine side effects by univariate analysis. The homozygous ABCB1 diplotype (GG-CC) conferred an odds ratio of 0.12 (95% confidence interval, 0.01-0.98) with regard to the use of ondansetron for postoperative nausea or vomiting. Multivariate analysis identified that the ABCB1 GG-CC diplotype was the only borderline-significant (P = .07) predictive factor of morphine side effects. CONCLUSION: Age and prior use of psychotropic agents are associated with postoperative morphine dose requirements. Whether ABCB1 polymorphisms might predict morphine side effects remains to be determined.

Inguinal herniorrhaphy under monitored anesthesia care with ilioinguinal-iliohypogastric block: the impact of adding clonidine to ropivacaine.

There is no information concerning the association of ropivacaine and clonidine for ilioinguinal-iliohypogastric block. In this prospective, double-blind study, we randomly assigned 40 adult patients scheduled for inguinal herniorrhaphy under monitored anesthesia care to receive either 225 mg ropivacaine (7.5 mg/mL) alone (control group) or combined with 75 mug clonidine (clonidine group) for preoperative ilioinguinal-iliohypogastric block. After completion of surgery, patients were transferred to the postanesthesia care unit and were asked to stand up and walk around at the second postoperative hour. After leaving the postanesthesia care unit, patients could take oral propacetamol (500 mg) and codeine (30 mg) on request. Pain intensity was assessed with a 100 mm visual analog scale. Time to first request of supplemental analgesics (median [95% confidence interval]) was 10 h (7.1-14.5 h) and 9 h (6.4->24 h) respectively in the clonidine and control groups (P = 0.83). Pain at rest did not differ between groups whereas pain at motion was reduced on the third postoperative day in the clonidine group. More patients who received clonidine experienced orthostatic hypotension upon standing up within the first postoperative hours (6 of 20 versus 1 of 20 in the control group; P < 0.05). In conclusion, the benefit of adding clonidine 75 mug to ropivacaine for ilioinguinal-iliohypogastric block for motion pain on the third postoperative day must be balanced with an increasing risk of orthostatic hypotension in the immediate postoperative period.