Abstract
Thirteen post-thoracotomy patients were entered into a double-blind, randomized clinical trial comparing the effects of epidural morphine (Group E) and intravenous morphine (Group 1) on postoperative respiratory depression.
Postoperative respiratory depression was assessed for 24 hours by (a) PaCO2 at 2, 6, 12 and 24 hours (b) hourly assessment of respiratory rate (RR) (c) presence of respiratory rate of less than ten breaths per min for greater than 5 min (SRR) (d) hypopnoealapnoea (H/A).
RR, SRR, and H/A were measured using respiratory inductive plethysmography. PaCO2 was significantly elevated at 2, 6 and 12 hours in Group E and only at two hours in Group 1. One of five patients in Group 1 had a single episode of SRR whereas five of eight patients in Group E had multiple episodes of SRR. None of the patients in Group 1 had H/A episodes, in contrast to six of eight in Group E who had numerous H/A episodes postoperatively. This difference was statistically significant. Multiple doses of epidural morphine produce an insidious and unpredictable change in respiratory pattern. Electronic monitoring is useful to assess those at risk of overdose and possible respiratory arrest.
Résumé
Treize patients ayant subi une thoracotomie ont été étudiés à double insu et d’une façon randomisée dans une étude clinique comparant les effets de la morphine épidurale (groupe E) et la morphine intraveineuse (groupe I) sur la dépression respiratoire post-opératoire.
La dépression respiratoire post-opératoire a été évaluée pour 24 heures par (a) la PaCO2 à 2, 6, 12 et 24 heures, (b) l’évaluation à toutes les heures de la fréquence respiratoire (RR), (c) la présence d’une fréquence respiratoire inférieure à dix par minute pour une durée supérieure à cinq minutes (SRR), (d) l’hypopnéel apnée (H/A).
Les paramètres RR, SRR, et H/A ont été mesurés par l’intermédiaire de la pléthysmographie inductive respiratoire. La PaCO2 était significativement plus élevée à 2, 6 et 12 heures dans le groupe E et uniquement à deux heures dans le groupe I. Un des cinq patients du groupe I a présenté un épisode unique de SRR alors que cinq des huit patients du groupe E ont présenté plusieurs épisodes de SRR. Aucun des patients du groupe I n’a présenté des épisodes de H/A, contrairement à six des huit patients du groupe E qui ont présenté plusieurs épisodes en période post-opératoire. Cette différence était statistiquement significative.
Plusieurs doses de morphine en injection épidurale produisent des changements insidieux et imprévisibles du schéma respiratoire. La surveillance électronique est utile afin d’évaluer ceux qui sont à risque de surdosage et possiblement d’arrêt respiratoire.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Cousins MJ, Mather LE. Intrathecal and epidural administration of opiods. Anesthesiology 1984; 61: 276–310.
McCaughey W, Graham JL. The respiratory depression of epidural morphine. Time course and effect of posture. Anaesthesia 1982; 37: 990–5.
Boas RA. Hazards of epidural morphine. Anaesth Intensive Care 1980; 8: 377–8.
Christiansen V. Respiratory depression after extradural morphine. Br J Anaesth 1980; 52: 841.
Reiz S, Westberg M. Side effects of epidural morphine. Lancet 1980; 2: 203–4.
Gustafsson LL, Schildt B, Jacobsen K. Adverse effects of extradural and intrathecal opiates: report of nationwide survey in Sweden. Br J Anaesth 1982; 54: 479–85.
Shulman M, Sandier AN, Bradley JW et al. Postthoracotomy pain and pulmonary function following epidural and systemic morphine. Anesthesiology 1984; 61: 569–75.
Shulman MS, Sandier AN, Brebner J. The reversal of epidural morphine induced somnolence with physostigmine. Can Anaesth Soc J. 1984; 31: 678–80.
Revill SI, Robinson JO, Roxen M et al. The reliability of a linear analogue for evaluating pain. Anaesthesia 1976; 31: 1191–8.
Cohn MA, Rao ASV, Brougdy M et al. The respiratory inductive plethysmograph: a new non-invasive monitor of respiration. Bull Eur Physiopathol Respir. 1982; 18:643–58.
Cately DM, Lehane JR, Thornton C et al. Monitoring the respiratory effects of analgesic drugs in the postoperative period: In: Lecture Notes in Medical Informatices – “Objective Decision-making; Systems Approach in Acute Disease.” Edited by Beneken JEW, Lavelle SM, Heidelberg, Springer-Verlag 1983, 209–16.
Catling JA, Pinto DM, Jordan C et al. Respiratory effects of analgesia after cholecystecomy: comparison of continuous and intermittent papaveretum. Br Med J 1980; 281: 478–80.
Catley DM, Thornton C, Jordan C et al. Postoperative respiratory depression associated with continuous morphine infusion. Br J Anaesth 1982; 55: 235.
Catley DM, Thornton C, Jordan C et al. Pronounced episodic oxygen desaturation in the postoperative period: its association with ventilatory pattern and analgesic regimen. Anesthesiology 1985, 63: 20–8.
Knill RL, Clement JL, Thompson WR. Epidural morphine causes delayed and prolonged ventilatory depression. Can Anaesth Soc J 1981; 28: 537–43.
Rawal N, Wattwill M. Respiratory depression after epidural morphine – an experimental and clinical study. Anesth Analg 1984; 63: 8–14.
Kafer ER, Brown JT, Scott D et al. Biphasic depression of ventilatory responses to CO2 following epidural morphine. Anesthesiology 1983; 58: 418–27.
Doblar DD, Muldoon SM, Abbrecht PH et al. Epidural morphine following epidural local anesthesia: effect on ventilatory and airway occlusion pressure responses to CO2. Anesthesiology 1981, 55: 423–8.
Weddel SJ, Ritter RR. Serum levels following epidural administration of morphine and correlation with relief of post-surgical pain. Anesthesiology 1981, 54: 210–4.
Chauvin M, Samii K, Schermann JM et al. Plasma concentration of morphine after i.m., extradural and intrathecal administration. Br J Anaesth 1981, 53: 911–13.
Moller IW, Vester-Anderson T, Steentoft A et al. Respiratory depression and morphine concentration in serum after epidural and intramuscular administration of morphine. Acta Anesthesiol Scand 1982, 26: 421–4.
Chadha TS, Watson H, Birch S et al. Validation of respiratory induction plethysmography using different calibration procedures. Am Rev Respir Dis 1982, 125: 644–9.
Tobin MJ, Chadha TS, Jenouri G et al. Breathing patterns. I. Normal subjects. Chest 1983,84:202–5.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Sandier, A.N., Chovaz, P. & Whiting, W. Respiratory depression following epidural morphine: A clinical study. Can Anaesth Soc J 33, 542–549 (1986). https://doi.org/10.1007/BF03014258
Issue Date:
DOI: https://doi.org/10.1007/BF03014258