Effect of a low-dose ketamine regimen on pain, mood, cognitive function and memory after major gynaecological surgery: a randomized, double-blind, placebo-controlled trial.
OBJECTIVE
Major gynaecological abdominal surgery is associated with moderate to severe postoperative pain, hyperalgesia and the need for multimodal analgesia to reduce high morphine consumption. A low-dose ketamine regimen appears to prevent postoperative hyperalgesia. We examined the potential beneficial effect of ketamine on postoperative pain management and cognitive function.


METHODS
Ninety patients were included in this double-blind, randomized, placebo-controlled study to test the efficacy and adverse effects of ketamine (as an intraoperative bolus of 0.15 mg kg-1, followed postoperatively by ketamine 0.5 mg per morphine 1 mg in a patient-controlled analgesia device). All patients received additionally ketoprofen. The main end-point was morphine consumption over the first 24 h. Secondary efficacy and safety end-points were morphine consumption during the titration period and during the patient-controlled analgesia period (48 h), the number of morphine-related adverse effects and the results of psychometric tests.


RESULTS
Ketamine, in combination with morphine and ketoprofen, did not improve postoperative pain scales and did not reduce morphine consumption and the incidence of morphine-related adverse effects. Ketamine did not modify mood, cognitive and memory functioning.


CONCLUSIONS
Adding a low dose of ketamine to an efficacious multimodal analgesic regimen did not improve analgesia after gynaecological surgery. Although this combination appears to be safe, the lack of benefit suggests that a low dose of ketamine should not be used for routine care.
Aubrun
F
F
Université Pierre et Marie Curie-Paris 6, Assistance Publique-Hôpitaux de Paris (AP-HP), Groupe hospitalier Pitié-Salpêtrière, Department of Anesthesiology and Critical Care, Paris, France. frederic.aubrun@psl.ap-hop-paris.fr
Gaillat
C
C
Rosenthal
D
D
Dupuis
M
M
Mottet
P
P
Marchetti
F
F
Coriat
P
P
Riou
B
B
D000293:Adolescent; D000328:Adult; D000339:Affect / Q000187:drug effects*; D000368:Aged; D016058:Analgesia, Patient-Controlled; D000700:Analgesics / Q000009:adverse effects / Q000627:therapeutic use; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000009:adverse effects; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage; D003071:Cognition / Q000187:drug effects*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D017558:Elective Surgical Procedures; D005260:Female; D013509:Gynecologic Surgical Procedures; D006801:Humans; D007649:Ketamine / Q000009:adverse effects / Q000627:therapeutic use*; D007660:Ketoprofen / Q000008:administration & dosage; D008570:Memory, Short-Term / Q000187:drug effects*; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects; D010149:Postoperative Pain / Q000188:drug therapy*; D011446:Prospective Studies; D011594:Psychometrics / Q000379:methods / Q000706:statistics & numerical data; D016896:Treatment Outcome
D000700:Analgesics; D000701:Analgesics, Opioid; D000894:Anti-Inflammatory Agents, Non-Steroidal; D007649:Ketamine; D009020:Morphine; D007660:Ketoprofen