J. N. Lunn

Policy for controlling pain after surgery: effect of sequential changes in management.

OBJECTIVE--To observe the effects of introducing an acute pain service to the general surgical wards of a large teaching hospital. DESIGN--A study in seven stages: (1) an audit of current hospital practice succeeded by the sequential introduction to the general surgical wards of (2) pain assessment charts; (3) an algorithm to allow more frequent use of intramuscular analgesia; (4) increased use of local anaesthetic techniques of wound infiltration and nerve blocks; (5) an information sheet for patients about postoperative pain; (6) the introduction of patient controlled analgesia; (7) a repeat audit of hospital practice. Data were collected on each patient 24 hours after operation. SETTING--University Hospital of Wales, which has both district general and tertiary referral functions. PATIENTS--2035 patients over nine months from all surgical specialties (excluding cardiac) at the hospital. General surgical operations were studied in detail and separated into major, intermediate, and minor for data collection. MAIN OUTCOME MEASURES--A change in the median visual analogue pain scores 24 hours after surgery for pain during relaxation, pain on movement, and pain on deep inspiration at each stage of the study. RESULTS--There was a reduction in median visual analogue scores during the study. The median (95% confidence interval) scores for pain during relaxation decreased from 45 (34 to 53) in stage 1 to 16 (10 to 20) in stage 7 for major surgical procedures. Pain on movement decreased from 78 (66 to 80) to 46 (38 to 48), and pain on deep inspiration decreased from 64 (48 to 78) to 36 (31 to 38). The reductions in median scores for intermediate and minor operative procedures showed similar patterns. CONCLUSIONS--The introduction of an acute pain service to the general surgical wards led to considerable improvement in the level of postoperative pain as assessed by visual analogue scores. Simple techniques of regular pain assessment and the more frequent use of intramuscular analgesia as a result of using an algorithm were particularly effective.

Anaesthesia-related surgical mortality

This is the report of the second of two studies conducted by the Association of Anaesthetists of Great Britain and Ireland based on anonymous reports of deaths within 6 days of anaesthesia. One hundred and ninety‐seven detailed reports were received during 1981; 43% were found by assessors to have nothing to do with anaesthesia, 41% to be partly due to, and 16% totally due to anaesthesia. These figures confirm earlier results reported by the same system. It is important to have the opinion of the two clinicians (anaesthetist and surgeon) separately and not to ignore either in a study which attempts to identify aspects of clinical medicine which might be improved.

Degree and Duration of Reversal by Naloxone of Effects of Morphine in Conscious Subjects

The effects of intravenous naloxone on several of the actions of intravenous morphine (mean dose 30 mg/70 kg) were studied in six volunteer subjects. Naloxone produced a well defined reversal of the respiratory depression, analgesia, and miotic and subjective effects of the morphine. The agonist action of morphine outlasted the antagonist action of a single dose of naloxone. The effect of repeated doses of naloxone was also short-lived, but continuous infusions were effective in maintaining reversal.

Postoperative analgesia after circumcision

A randomised blind comparison between caudal analgesia (1.5 mg/kg bupivacaine) and intramuscular morphine (0.15 mg/kg) is reported. Forty boys were studied. Caudal analgesia is shown to be significantly better than morphine by means of a linear analogue scale designed to quantify behaviour immediately after operation.

A survey of acute pain services in the United Kingdom

The report of a joint working party of the Royal College of Surgeons of England and the College of Anaesthetists to consider pain after surgery called for the development of an acute pain service in every hospital performing surgery.1 Despite this firm recommendation, it is perceived that such services are not as prevalent as might be expected. We undertook a survey of the current status of acute pain management in the United Kingdom. We sent a questionnaire to each of the tutors of the Royal College of Anaesthetists. The questionnaire sought details of the existence, staffing, and funding of any form of acute pain service in each hospital. An outline of the hospitals current methods of pain management after major …

A comparative study of the narcotic agonist activity of naloxone and levallorphan

Naloxone, the n-ally1 derivative of the narcotic* analgesic oxymorphone, has been shown to possess narcotic antagonist properties, without obvious agonist activity, in animals and anaesthetised man.” A comparison of the respiratory and circulatory effects of naloxone, levallorphan and nalorphine in anaesthetised patients demonstrated that, whereas naloxone had virtually no effect, the other drugs were respiratory depressant^.^ When naloxone was administered in large doses to former narcotic addicts there was no evidence of agonist a ~ t i v i t y . ~ Naloxone therefore appears to be a relatively ‘pure’ narcotic antagonist with considerable therapeutic potential, notably in anaesthesia, obstetrics and the management of drug overdose or abuse but a direct cornparison of the agonist activity of naloxone and another antagonist following intravenous administration in unmedicated subjects has not, hitherto, bccn made. A comparison of the agonist activity of naloxone with that of another narcotic antagonist was therefore planned. Levallorphan was chosen as the standard for comparison since it produces less respiratory depression and fewer psychotomimetic side effects than nalorphine.’

A comparison between mivacurium and suxamethonium in children

The neuromuscular effects of mivacurium were compared with those of suxamethonium in 69 children (aged 2–12 years), during nitrous oxide, oxygen and halothane anaesthesia in a randomised open study. Neuromuscular block was monitored by measuring the acceleration of the thumb caused by contraction of the adductor pollicis muscle after supramaximal stimulation of the ulnar nerve at the wrist using an Accelograph. End‐tidal carbon dioxide was maintained at about 4 kPa in both groups. The mean times (95% confidence intervals) for T1: T0 ratio to decrease to 75%, 50%, 25% and 5% of control values were 50 (42–59), 62 (52–74), 83 (68–100) and 93 (46–108) s respectively for mivacurium and 18 (15–22), 26 (22–30), 32 (28–37) and 43 (38–49) s respectively for suxamethonium. The times for T1: T0 ratio to recover to 25%, 50% and 70% of control values were 615 (542–698), 769 (687–859) and 901 (820–993) s respectively for mivacurium and 196 (179–214), 216 (201–234) and 242 (216–259) s respectively for suxamethonium. The range of maximum block was similar for both drugs. The average time to reach maximum block was 143 s for mivacurium and 56 s for suxamethonium. Intubating conditions were similar in the two groups.

A new anaesthetic record

Record‐keeping is part of the proper practice of anaesthesia and a record should be able to be quickly and easily completed. Two types of information need to be recorded: clinical, for use both immediately or subsequently and epidemiological, for detailed study of a large number of anaesthetics. A design which answers both these aims is described.

Glycopyrrolate in children. A comparison between the effects of glycopyrrolate and atropine administered before induction of anaesthesia.

The effect of intravenous administration of glycopyrrolate and atropine shortly before induction were compared in a double blind study in children. The study shows that glycopyrrolate, unlike atropine, administered before anaesthesia had little effect on heart rate. The heart rate changes at, and following, tracheal intubation were similar in both groups.

Measurements of compliance in apnoeic anaesthetised infants.

Airway pressure was measured at a point near the mouth end of the endotracheal tube. Oesophageal pressure, changes of which represent changes of intra-pleural pressure, was recorded by means of an intra-oesophageal balloon at the end of a tube, 60cm long, with an internal diameter of 0.2cm. The balloon itself was 1.5cm long and there were holes cut in the tube so that the pressure changes were: faithfully recorded. The balloon was sited in the middle third of the oesophagus at the position which gave rise to the largest amplitude of pressure variation in response to respiration. The differential pressure between airway and oesophagus was recorded by means of a defocussing manoimeter11 whose output was used to drive a pen recorder (Newmark Instruments Ltd, Cardette). A 5Oml syringe (figure 1) was used for introducing known volumes of gas into the lungs. This syringe was mounted on a board and so arranged that at each 5ml point an electrical circuit wa:3 completed and a signal could be superimposed upon the pressure trace. The infants were premedicatled and anaesthetised in a similar manner to that described elsewhere12. The trachea was intubated with the largest size of latex, nylon reinforced., endotracheal tube that could be accommodated and the pharynx was packed. This precaution ensured that any leak was minimal. Measurements were made during apnoea produced by muscle relaxants. Those patients whose ventilation was controlled had