[Differential administration of non-opioids in postoperative analgesia, I. Quantification of the analgesic effect of metamizole using patient-controlled analgesia].
OBJECTIVE
The aim of this study was to investigate: 1. Whether the perioperative administration of metamizol causes a significant reduction in postoperative opioid requirements within the first 24 h after surgery. 2. The opioid-sparing effect after different types of operations. 3. Whether preoperative application of metamizol causes a significant reduction of the pain-score immediately after operation.


METHODS
In a double-blind, randomised, placebo-controlled study, 117 patients, scheduled for minor orthopaedic or laparoscopic surgery or other operations (mainly resection of the thyroid gland and inguinal herniotomies) received either metamizol (1 g/100 ml NaCl 0.9%) or placebo (100 ml NaCl 0.9%) intravenously over 15 min in three separate doses: the first dose was given just before induction and the others 6 h and 12 h later. After surgery all patients were allowed to self-administer buprenorphine from a PCA (patient-controlled analgesia) pump (Bolus: 30 microgram, lockout: 5 min in the recovery room, 30 min on the ward). Every hour for the first 6 h and after 24 h, cumulated doses of buprenorphine, pain scores (0-10), blood pressure, pulse and side effects were recorded.


RESULTS
After minor orthopaedic and laparoscopic surgery, metamizol-treated patients had significantly less pain immediately after surgery and used a significantly lower cumulated dose of opioid in the first 24 h after surgery (-20% and -67% respectively) than patients receiving placebo. After the other types of surgery no analgesic effect could be established.


CONCLUSIONS
Perioperative administration of metamizol results in better pain relief and significantly lower buprenorphine requirements particularly after laparoscopic operations. To achieve a significant pain reduction immediately after the operation, the first dose should be applied before induction.
Steffen
P
P
Klinik für Anästhesiologie der Universität Ulm.
Schuhmacher
I
I
Weichel
T
T
Georgieff
M
M
Seeling
W
W
D000293:Adolescent; D000328:Adult; D000368:Aged; D016058:Analgesia, Patient-Controlled; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000009:adverse effects; D004177:Dipyrone / Q000008:administration & dosage* / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy* / Q000209:etiology; D011229:Preanesthetic Medication
D000894:Anti-Inflammatory Agents, Non-Steroidal; D004177:Dipyrone
Untersuchungen zum differenzierten Einsatz von Nichtopioiden zur postoperativen Analgesie I. Quantifizierung des analgetischen Effektes von Metamizol mittels der patientenkontrollierten Analgesie.