<i>A Study on the Mechanism of Nitrous Oxide Analgesia</i>

Sonnenschein, Ralph R.; Jamison, Rex L.; Loveseth, L. J.; Cassels, W. H.; Ivy, A. C.

doi:10.1152/jappl.1948.1.3.254

Cited by 14 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Post-operative pain in such patients restricts breathing to a marked degree, and the relief by analgesics of this restriction can be assessed by simple tests of vital capacity in the manner described by Overholt (1930), Bromage (1955), and Masson (1962. Previous work on volunteers (Chapman et al, 1943 ;Sonnenschein et al, 1948 ;Delisle Burns et al, 1960;Dundee and Moore, 1960;Parkhouse et al, 1960;Dundee et al, 1962) suggested that 25% nitrous oxide in oxygen was the most suitable concentration for this study. …”

mentioning

confidence: 90%

Relief of Post-operative Pain: Comparison of a 25% Nitrous-oxide and Oxygen Mixture with Morphine

Parbrook¹,

Rees²,

Robertson³

1964

BMJ

View full text Add to dashboard Cite

Nitrous oxide has had a wide use as an analgesic in midwifery and in dental surgery, but its use does not appear to have been investigated for the relief of post-operative wound pain.We describe here a study designed to compare the relative potency of nitrous oxide and morphine for relief of pain in patients during the first 48 hours after upper abdominal operations. Post-operative pain in such patients restricts breathing to a marked degree, and the relief by analgesics of this restriction can be assessed by simple tests of vital capacity in the manner described by Overholt (1930), Bromage (1955), and Masson (1962. Previous work on volunteers (Chapman et al., 1943 ;Sonnenschein et al., 1948 ;Delisle Burns et al., 1960;Dundee and Moore, 1960;Parkhouse et al., 1960;Dundee et al., 1962) suggested that 25% nitrous oxide in oxygen was the most suitable concentration for this study. Material and MethodsThe investigation was limited to patients under the age of 60 who had operation wounds in or extending to the upper abdomen. Prior to operation the patients were seen, the nature of the trial was explained, and their co-operation obtained; vital capacity and peak expiratory flow readings were then measured and the nitrous oxide and oxygen breathing apparatus was demonstrated.If vital capacity is measured before operation and again after operation, when the patient is fully recovered from the anaesthetic, its diminution gives some measure of the impairment of respiratory movement. This can be taken as some measure of the degree of pain. If this pain is then relieved by an analgesic the vital capacity increases in proportion to the efficacy of the drug. A perfect analgesic will restore the vital capacity to virtually the pre-operative value, whereas a drug having no effect will make no difference to the vital capacity. We therefore used changes in vital capacity, and, to a less extent, those in peak expiratory flow rate, as a way of assessing the analgesic effects of nitrous oxide and morphine.Vital Capacity.-This was measured by the Wright respirometer used with a mouth-piece and Ruben valve, and with a nose-clip applied. After practice readings the mean of three readings was noted. Although the Wright respirometer is less accurate than bulkier apparatus for vital capacity measurement, it was thought to give satisfactory comparative readings since the same respirometer was used in every case.Peak Expiratory Flow Rate.-The Wright peak flow meter was used and the mean of three readings taken after practice " puffs." 25% Nitrous Oxide in Oxygen Mixture.-The mixture was delivered to the patient from a specially calibrated Walton 5 machine using a reservoir bag and a non-rebreathing circuit with a Ruben valve. The " pressure " control was adjusted so that the reservoir bag did not collapse during inspiration while

show abstract

mentioning

confidence: 90%

Relief of Post-operative Pain: Comparison of a 25% Nitrous-oxide and Oxygen Mixture with Morphine

Parbrook¹,

Rees²,

Robertson³

1964

BMJ

View full text Add to dashboard Cite

show abstract

“…On the other hand, the 15 minutes permitted in this trial is probably adequate for initial equilibration of arterial to alveolar tension of nitrous oxide (Kety andSchmidt, 1945, 1948), although an uneven ventilation-perfusion relationship may be present in the patients (Nunn and Payne, 1962 ;Palmer and Gardiner, 1964). The side-effects to be expected with slightly higher concentrations of nitrous oxide have been investigated in volunteers by several workers (Seevers et al, 1937 ;Sonnenschein et al, 1948 ;Steinberg, 1953Steinberg, , 1956Delisle Burns et al, 1960;Parkhouse et al, 1960;Robson et al, 1960). As the concentration of nitrous oxide is raised from 30% to 40% there is a progressive impairment of memory and of time sense and rise of sensory thresholds.…”

Section: Resultsmentioning

confidence: 99%

Value of Premixed Nitrous-oxide-and-oxygen Mixtures in the Relief of Post-operative Pain

Parbrook¹,

Kennedy²

1964

BMJ

View full text Add to dashboard Cite

x524781; n=3; 02>P>0-1.4. The last aspect of behaviour to be considered is delinquency. We know of all children who are brought before the courts between the ages of 8 and 17. The proportions are closely similar for those having measles before the age of 6 (4.9% delinquent) and for those having measles later or not at all (4.7% delinquent),3 so that there is no evidence that early measles is associated with troublesome behaviour in later school life. SummaryThe National Survey of Health and Development provides information about the history of measles, and the educational progress and emotional stability of 3,729 children who were followed up over a period of 15 years. There is no suggestion from this survey that children who have measles are impaired in their later educational progress. Those who get measles early, before the age of 2, do rather worse in tests of mental ability and school performance than the rest of the children, but this is sufficiently explained by their adverse home circumstances.There is also no evidence from this survey that children who get measles early show an excess of later abnormalities of behaviour; indeed, those who get measles late are rather more nervous than the rest, perhaps because they have been overprotected in infancy and childhood. These conclusions are by no means incompatible with those of the much larger survey made by Miller (1964) Overholt (1930), and Bromage (1955), and Masson (1962, who showed that wound pain reduces the vital capacity of patients after operation, and the degree of improvement of the vital capacity with treatment can be used to provide an index of the degree of pain relief. Apparatus and MethodComparative vital capacity readings were obtained using a Wright respirometer with a rubber mouth-piece attached and a nose-clip in situ. Three consecutive readings were taken on

show abstract

“…The cardiorespiratory depressant actions attributed to nitrous oxide (Sonnerstein et al, 1948;Parbrook, 1967) may be partly counteracted by the high oxygen concentration in the Entonox to provide effects on the diastolic blood pressure and heart rate that causes variation in the Oxygen and Entonox treatment groups. Naturally, since oxygen is always required to be used when nitrous oxide is being given, this can only be speculation.…”

Section: Discussionmentioning

confidence: 99%

Minor procedures in the accident and emergency department: can Entonox help?

Payne

Edbrooke²,

Davies³

1991

Emergency Medicine Journal

View full text Add to dashboard Cite

SUMMARYThe efficacy of Entonox as a supplement to local anaesthesia for minor surgical procedures was studied. Eighty-five patients undergoing surgery for the incision and drainage of a subcutaneous abscess using a local anaesthetic were involved in a trial to ascertain the level of pain associated with such procedures and to investigate the possibility of using on-demand Entonox to supplement the local anaesthesia provided. Patients received either the standard local anaesthesia, or, alternatively, the local anaesthesia was supplemented with oxygen or Entonox via on-demand apparatus.Patients indicated on three linear visual analogue scales their pain, anxiety and total discomfort, and also on a cartoon pain rating scale, at different stages during the operation.Results showed that there was no statistically significant reduction in pain provided by the Entonox, despite general patient approval. Both oxygen and Entonox showed some anxiolytic properties. Pure oxygen was also seen to produce a rise in heart rate, while both gases (pure oxygen and Entonox) caused an increase in diastolic blood pressure. It was also seen that the patient's short term memory of the pain experienced was unaffected by pure oxygen or Entonox.

show abstract

A Study on the Mechanism of Nitrous Oxide Analgesia

Cited by 14 publications

References 0 publications

Relief of Post-operative Pain: Comparison of a 25% Nitrous-oxide and Oxygen Mixture with Morphine

Relief of Post-operative Pain: Comparison of a 25% Nitrous-oxide and Oxygen Mixture with Morphine

Value of Premixed Nitrous-oxide-and-oxygen Mixtures in the Relief of Post-operative Pain

Minor procedures in the accident and emergency department: can Entonox help?

Contact Info

Product

Resources

About