RESUMEN
BACKGROUND: Intravenous acetaminophen injection (paracetamol) is marketed in Europe for the management of acute pain. A repeated-dose, randomized, double-blind, placebo-controlled, three-parallel group study was performed to evaluate the analgesic efficacy and safety of intravenous acetaminophen as compared with its prodrug (propacetamol) and placebo. Propacetamol has been available in many European countries for more than 20 yr. METHODS: After orthopedic surgery, patients reporting moderate to severe pain received either 1 g intravenous acetaminophen, 2 g propacetamol, or placebo at 6-h intervals over 24 h. Patients were allowed "rescue" intravenous patient-controlled analgesia morphine. Pain intensity, pain relief, and morphine use were measured at selected intervals. Safety was monitored through adverse event reporting, clinical examination, and laboratory testing. RESULTS: One hundred fifty-one patients (intravenous acetaminophen: 49; propacetamol: 50; placebo: 52) received at least one dose of study medication. The intravenous acetaminophen and propacetamol groups differed significantly from the placebo group regarding pain relief from 15 min to 6 h (P < 0.05) and median time to morphine rescue (intravenous acetaminophen: 3 h; propacetamol: 2.6 h; placebo: 0.8 h). Intravenous acetaminophen and propacetamol significantly reduced morphine consumption over the 24-h period: The total morphine doses received over 24 h were 38.3 +/- 35.1 mg for intravenous acetaminophen, 40.8 +/- 30.2 mg for propacetamol, and 57. 4 +/- 52.3 mg for placebo, corresponding to decreases of -33% (19 mg) and -29% (17 mg) for intravenous acetaminophen and propacetamol, respectively. Drug-related adverse events were reported in 8.2%, 50% (most of them local), and 17.3% of patients treated with intravenous acetaminophen, propacetamol, and placebo, respectively. CONCLUSION: Intravenous acetaminophen, 1 g, administered over a 24-h period in patients with moderate to severe pain after orthopedic surgery provided rapid and effective analgesia and was well tolerated.
Asunto(s)
Acetaminofén/efectos adversos , Acetaminofén/uso terapéutico , Analgésicos no Narcóticos/efectos adversos , Analgésicos no Narcóticos/uso terapéutico , Procedimientos Ortopédicos , Dolor Postoperatorio/tratamiento farmacológico , Acetaminofén/administración & dosificación , Anciano , Analgesia Controlada por el Paciente , Analgésicos no Narcóticos/administración & dosificación , Analgésicos Opioides/uso terapéutico , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Método Doble Ciego , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Morfina/uso terapéutico , Dimensión del Dolor/efectos de los fármacos , Profármacos/administración & dosificación , Profármacos/efectos adversos , Profármacos/uso terapéutico , Tamaño de la MuestraRESUMEN
This multicenter, randomized, double-blind, placebo-controlled study evaluated the analgesic efficacy and opioid-sparing effects of valdecoxib, a potent COX-2 specific inhibitor, in patients undergoing knee replacement. Patients received morphine by patient-controlled analgesia (PCA), and valdecoxib 40 mg or 80 mg daily, or placebo, for up to two days. Efficacy was assessed by the cumulative amount of morphine administered over 48 hours, pain intensity and patient's evaluation of medication. Morphine consumption over 48 hours by patients receiving valdecoxib 40 mg or 80 mg daily plus morphine was 83.7% and 75.8% (P < 0.05) of the total amount consumed by patients receiving morphine alone. Patients receiving valdecoxib 40 mg and 80 mg daily experienced significantly lower maximum pain intensity on Day 2 (P < 0.05), and rated their study medication significantly higher than patients receiving morphine alone. Valdecoxib plus morphine was well tolerated. Thus, valdecoxib in combination with morphine provides multi-modal analgesia that reduces pain and opioid use and increases patient satisfaction following knee replacement surgery.