PASTIES study findings

An open randomised trial of patient controlled analgesia (PCA) versus routine care in the Emergency Department

Introduction

Pain is very common in patients attending emergency departments (A&E Departments, or EDs), but is often difficult to treat effectively. If a patient is in severe pain in the ED they usually receive morphine through a drip, administered by a nurse.

A patient-controlled analgesia (PCA) device is a syringe usually containing morphine that can be connected to a drip in the patient’s arm, which allows the patient to deliver their own pain relief by pressing a button. PCA devices are commonly used in other areas of the hospital (typically after an operation), but are not usually used in the ED. This study compared pain relief using a PCA to the normal pain relief delivered by a nurse in adult emergency patients in pain who are subsequently admitted to hospital. The study aimed to see if giving patients a PCA device in the ED, and during the first few hours of their stay in hospital, improved pain relief and patient satisfaction.

Methods

396 patients who attended emergency departments with either non-traumatic abdominal pain or pain from traumatic injury were recruited across five English hospitals and included in the results. Patients who were eligible and willing to take part were randomly allocated to receive either PCA or routine care, and asked to score their pain hourly over a 12 hour study period. In addition to morphine, all participants in the study were offered other forms of painkillers as necessary. On completion of the 12 hour study period, participants were asked to score their satisfaction with their pain relief. By comparing the two methods of pain relief we have been able to assess whether one method was, on average, better than the other in terms of pain control and satisfaction. Because there were two separate patient populations ((i) patients with non-traumatic abdominal pain (ii) patients with traumatic injuries), the study was run as two separate trials with the same aims and questions. Cost-effectiveness was also evaluated, although the results of this evaluation have yet to be published. An observational study was carried out on a sample of patients allocated to PCA and routine care in Plymouth and London. Information was collected on the resources required (personnel and time) for the set-up of the PCA and the administering of routine care.

Results and discussion

This is the first study to investigate pain in patients during the first few hours of their attendance at the emergency department through to their admission to a hospital ward, and has given a pragmatic answer to the question of whether PCA should be used in these patients. This study has shown that PCA is significantly more effective than normal care in managing pain in patients with non-traumatic abdominal pain. For participants with traumatic injuries, the results were more unclear and we cannot be sure whether PCA offers any advantages to this group. The use of PCA in emergency departments allows patients to manage their own pain, which may improve overall patient satisfaction with their pain relief. Emergency patients with abdominal pain who were given a PCA showed a modest reduction in overall pain scores and a significant reduction in the amount of time spent in moderate and severe pain. Significantly more morphine was used in the PCA group, although this was still completely safe, which may reflect under-treatment in the routine care group. Patient satisfaction in the abdominal pain group showed a marked difference, with a significant increase in satisfaction in those patients allocated to PCA. Emergency patients with traumatic injuries who were given a PCA showed no significant reduction in overall pain scores. There was a reduction in the amount of time that patients spent in moderate to severe pain with PCA which was reflected in the higher percentage of participants in the PCA group being perfectly or very satisfied. However, neither of these findings were statistically significant.

Conclusion

Significant reductions in pain can be achieved by using PCA compared to routine care in emergency patients with non-traumatic abdominal pain. Emergency patients with traumatic injuries who were given a PCA showed no significant reduction in overall pain scores. There was a reduction in the amount of time that patients spent in moderate to severe pain with PCA which was reflected in the higher percentage of participants in the PCA group being perfectly or very satisfied. However, neither of these findings were statistically significant.

The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health.

This research was funded by the National Institute for Health and Care Research (NIHR)’s Research for Patient Benefit (RfPB) Programme, grant reference number PB-PG-0909-20048.

This unit receives National Institute for Health and Care Research CTU Support Funding. This funding has been awarded to support the unit in developing and supporting NIHR trials.