These results suggest that the UK Audit Commission (1997) proposed standards of care might be unachievable using current analgesic techniques. The data may be useful in setting standards of care for Acute Pain Services.

Background. This study examines the evidence from published data concerning the adverse respiratory and haemodynamic effects of three analgesic techniques after major surgery; i.m. analgesia, patient-controlled analgesia (PCA), and epidural analgesia.Methods. A MEDLINE search of the literature was conducted for publications concerned with the management of postoperative pain. Information relating to variables indicative of respiratory depression and of hypotension was extracted from these studies. Over 800 original papers and reviews were identified. Of these papers, 212 fulfilled the inclusion criteria but only 165 provided usable data on adverse effects. Pooled data obtained from these studies, which represent the experience of a total of nearly 20 000 patients, form the basis of this study.Results. There was considerable variability between studies in the criteria used for defining respiratory depression and hypotension. The overall mean (95% CI) incidence of respiratory depression of the three analgesic techniques was: 0.3 (0.1-1.3)% using requirement for naloxone as an indicator; 1.1 (0.7-1.7)% using hypoventilation as an indicator; 3.3 (1.4-7.6)% using hypercarbia as an indicator; and 17.0 (10.2-26.9)% using oxygen desaturation as an indicator. For i.m. analgesia, the mean (95% CI) reported incidence of respiratory depression varied between 0.8 (0.2-2.5) and 37.0 (22.6-45.9)% using hypoventilation and oxygen desaturation, respectively, as indicators. For PCA, the mean (95% CI) reported incidence of respiratory depression varied between 1.2 (0.7-1.9) and 11.5 (5.6-22.0)%, using hypoventilation and oxygen desaturation, respectively, as indicators. For epidural analgesia, the mean (95% CI) reported incidence of respiratory depression varied between 1.1 (0.6-1.9) and 15.1 (5.6-34.8)%, using hypoventilation and oxygen desaturation, respectively, as indicators. The mean (95% CI) reported incidence of hypotension for i.m. analgesia was 3.8 (1.9-7.5)%, for PCA 0.4 (0.1-1.9)%, and for epidural analgesia 5.6 (3.0-10.2)%. Whereas the incidence of respiratory depression decreased over the period 1980-99, the incidence of hypotension did not.Conclusions. Assuming a mixture of analgesic techniques, Acute Pain Services should expect an incidence of respiratory depression, as defined by a low ventilatory frequency, of less than 1%, and an incidence of hypotension related to analgesic technique of less than 5%.

This review examines the evidence from published data concerning the tolerability (indicated by the incidence of nausea, vomiting, sedation, pruritus, and urinary retention), of three analgesic techniques after major surgery; intramuscular analgesia (i.m.), patient-controlled analgesia (PCA), and epidural analgesia. A MEDLINE search of publications concerned with the management of postoperative pain and these indicators identified over 800 original papers and reviews. Of these, data were extracted from 183 studies relating to postoperative nausea and vomiting, 89 relating to sedation, 166 relating to pruritus, and 94 relating to urinary retention, giving pooled data which represent a total of more than 100,000 patients. The overall mean (95% CI) incidence of nausea was 25.2 (19.3-32.1)% and of emesis was 20.2 (17.5-23.2)% for all three analgesic techniques. PCA was associated with the highest incidence of nausea but the emesis was unaffected by analgesic technique. There was considerable variability in the criteria used for defining sedation. The overall mean for mild sedation was 23.9 (23-24.8)% and for excessive sedation was 2.6 (2.3-2.8)% for all three analgesic techniques (significantly lower with epidural analgesia). The overall mean incidence of pruritus was 14.7 (11.9-18.1)% for all three analgesic techniques (lowest with i.m. analgesia). Urinary retention occurred in 23.0 (17.3-29.9)% of patients (highest with epidural analgesia). The incidence of nausea and excessive sedation decreased over the period 1980-99, but the incidence of vomiting, pruritus, and urinary retention did not. From these published data it is possible to set standards of care after major surgery for nausea 25%, vomiting 20%, minor sedation 24%, excessive sedation 2.6%, pruritus 14.7%, and urinary retention requiring catheterization 23%. Acute Pain Services should aim for incidences less than this standard of care.

Patients may wait some time for total hip replacement with conservative management of pain and disability, but no attempts to rehabilitate them. This study randomised 40 patients accepted for and awaiting total hip replacement to a brief rehabilitative psychologically based pain management programme (PMP) or to a control group with no intervention. Patients were assessed before randomisation, 3 months after the PMP or equivalent waiting time, and again one year later after total hip replacement. Assessments included pain, impact of pain (Arthritis Impact Scale: AIMS), mobility (timed walk), sleep and analgesic consumption. The patients who had learned pain management reported lower pain intensity and pain distress and less sleep disturbance than waiting list controls, but no improvement in function or analgesic consumption. Six patients opted to delay, but this did not differ between groups. Post-hip replacement both groups improved in pain and some aspects of activity (AIMS) with greater improvement in the PMP group for physical activity and total AIMS scores, suggesting that some techniques had continued to be of use post-surgically. Rehabilitative pain management may be useful to patients pre-operatively in managing everyday pain, but not to the extent that they opt to delay surgery; it may also improve their function after hip replacement.