Efficacy of an intravenous bolus of morphine 2.5 versus morphine 7.5 mg for procedural pain relief in postoperative cardiothoracic patients in the intensive care unit: a randomised double-blind controlled trial

• Published in: Anaesthesia and intensive care 2012-05, Vol.40 (3), p.417-426
• Main Authors: AHLERS, S. J. G. M, VAN GULIK, L, VAN DONGEN, E. P. A, BRUINS, P, VAN DE GARDE, E. M. W, VAN BOVEN, W. J, TIBBOEL, D, KNIBBE, C. A. J
• Format: Article
• Language: English
• Subjects: Aged; Analgesics, Opioid - administration & dosage; Analgesics, Opioid - therapeutic use; Anesthesia; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Cardiac Surgical Procedures; Care and treatment; Critical Care; Critical care medicine; Dosage and administration; Dose-Response Relationship, Drug; Double-Blind Method; Drug therapy; Endpoint Determination; Female; Heart; Humans; Injections, Intravenous; Male; Medical sciences; Methods; Middle Aged; Morphine; Morphine - administration & dosage; Morphine - therapeutic use; Pain; Pain Measurement; Pain, Postoperative; Pain, Postoperative - drug therapy; Prospective Studies; Sample Size; Surgery; Thoracic Surgical Procedures
• ISSN: 0310-057X; 1448-0271
• DOI: 10.1177/0310057X1204000306

As pain in the intensive care unit (ICU) is still common despite important progress in pain management, we studied the efficacy of an intravenous bolus of morphine 2.5 vs 7.5 mg for procedural pain relief in patients after cardiothoracic surgery in the ICU. In a prospective double-blind randomised study, 117 ICU patients after cardiothoracic surgery were included. All patients were treated according a pain titration protocol for pain at rest, consisting of continuous morphine infusions and paracetamol, applied during the entire ICU stay. On the first postoperative day, patients were randomised to intravenous morphine 2.5 (n=59) or 7.5 mg (n=58) 30 minutes before a painful intervention (turning of patient and/or chest drain removal). Pain scores using the numeric rating scale (Numeric Rating Scale, range 0 to 10) were rated at rest (baseline) and around the painful procedure. At rest (baseline), overall incidence of unacceptable pain (Numeric Rating Scale ≥4) was low (Numeric Rating Scale >4; 14 vs 17%, P=0.81) for patients allocated to morphine 2.5 and 7.5 mg respectively. For procedure-related pain, there was no difference in incidence of unacceptable pain (28 vs 22%, P=0.53) mean pain scores (2.6 [95% confidence interval 2.0 to 3.2] vs 2.7 [95% confidence interval 2.0 to 3.4]) between patients receiving morphine 2.5 and 7.5 mg respectively. In intensive care patients after cardiothoracic surgery with low pain levels for pain at rest, there was no difference in efficacy between intravenous morphine 2.5 mg or morphine 7.5 mg for pain relief during a painful intervention.