[Postoperative patient-controlled analgesia is more effective with epidural methadone than with intravenous methadone in thoracic surgery].
OBJECTIVE
To compare the efficacy and side effects of epidural and intravenous methadone for postoperative patient-controlled analgesia (PCA) after thoracic surgery.


METHODS
A randomized, single-blind trial enrolling 30 patients distributed in 2 groups to receive intravenous methadone (ivPCA group) or epidural methadone (epPCA group). Patients in both groups were administered a loading dose of 0.05 mg.kg-1 followed by infusion of 0.5 mg.h-1. The patients could self-dose 0.5 mg with a lock-out interval of 10 minutes and a maximum of 4 doses per hour. Patient characteristics, type and duration of surgery and fentanyl dose were recorded. Pain was assessed on a visual analog scale (VAS). Level of sedation, respiratory rate and occurrence of nausea, vomiting and pruritus were also recorded over the first 24 hours.


RESULTS
The 2 groups were comparable. Pain was greater in the ivPCA group than in the epPCA group in the second hour (VAS 3.93 +/- 1.9 and 2.4 +/- 1.65, respectively; P < .05) and the third hour (VAS 3.57 +/- 1.65 and 1.5 +/- 1.16, respectively; P < .05). The total dose of methadone administered was 25.34 +/- 5.65 mg in the ivPCA group and 18.82 +/- 3.52 mg in the epPCA group (P < .002). There were no significant differences in side effects.


CONCLUSIONS
The results suggest that epidural methadone has an intrinsic spinal effect regardless of whether or not there is extra-spinal action arising from syste mic absorption. Epidural methadone provides a more adequate analgesic effect in less time and at a lower dose. Both approaches provide good postoperative analgesia with few side effects.
Parramon
F
F
Servei d'Anestesiologia, Reanimació i Terapeutica del Dolor, Hospital Universitari de Girona Dr. Josep Trueta, Avd. França, s/n, 17001 Girona. anestesia@htrueta.scs.es/fparramon@comg.es
García
Ch
Ch
Gambús
P
P
Vilaplana
J
J
Aragonés
N
N
Villalonga
A
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015360:Analgesia, Epidural / Q000009:adverse effects; D016058:Analgesia, Patient-Controlled / Q000009:adverse effects / Q000379:methods*; D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008691:Methadone / Q000008:administration & dosage* / Q000009:adverse effects; D008875:Middle Aged; D010149:Postoperative Pain / Q000188:drug therapy*; D011446:Prospective Studies; D016037:Single-Blind Method; D013908:Thoracotomy
D000701:Analgesics, Opioid; D008691:Methadone