Morphine combined with doxapram or naloxone*

Abstract

The ability to produce adequate analgesia by opiates without the concomitant risk of respiratory depression would be highly desirable. However, it is well recognised that the antagonists nalorphine and levallorphan reduce the analgesic action of opiates as well as minimising respiratory depression and it is generally agreed that agonist-antagonist mixtures are not of value in this field.Recently, Dundee, Gupta & Jones' have shown that clinical doses of the respiratory stimulant doxapram had no effect on the analgesic action of pethidine or morphine, but these studies were carried out using an experimental pain stimulus. This paper reports a study carried out in patients after upper abdominal surgery to whom doxapram was given at three dose levels combined with large doses of morphine; the degree of analgesia was compared with that after morphine alone, The new opiate antagonist naloxone was also studied at one dose level.This study was initiated to determine whether clinically used doses of doxapram or naloxone interfere with morphine-induced analgesia and to assess the extent to which these two drugs attenuate morphine-induced respiratory depression in this clinical situation.As post-operative pulmonary complications are a recognised hazard of upper abdominal surgery, the effects of concomitant administration of doxapram or naloxone with morphine on the incidence of such complications was also investigated. MethodsThe study was carried out in the recovery ward of the Royal Victoria Hospital, Belfast, in adult patients following upper abdominal surgery. No patients were admitted to the trial who were outside the 16-70 age, or 50-75 kg weight, groups, who had had any analgesic during surgery or who suffered from any severe systemic

Effect of Doxapram on the Rate of Recovery From Atracurium and Vecuronium Neuromuscular Block

“…The analeptic agent, doxapram, is often used at the end of anaesthesia to stimulate ventilation and accelerate recovery from the effects of volatile anaesthetic agents without antagonizing analgesia [ 1,2]. A recent experimental study has demonstrated that it may enhance a partial neuromuscular block by agents such as tubocurarine [3].…”

Effect of Doxapram on Neostigmine Evoked Antagonism of Vecuronium Neuromuscular Block

“…Doxapram is a potent respiratory stimulant which has been used in clinical practice for many years. The mode of action of doxapram is thought to be related to an increase in the sensitivity of both central and peripheral chemoreceptors [1][2][3].…”