A study of pain assessment tools among women undergoing manual vacuum aspiration of retained products of conception at the University Teaching Hospital, Lusaka, Zambia

Abstract

Background: Pain is subjective and its assessment is dependent on self-report. Evaluation of cause, type and severity helps in the selection of the appropriate therapeutic regimen and the assessment of the effectiveness of the therapy. To establish whether a particular pain intervention is effective or not, the best method for clinical research and practice is the use of simple pain assessment tools. The tool must be relevant to the setting understandable by the users and responsive to change in pain levels, taking into account tool content and patient factors. Limited reports regarding pain assessment in low income and low education settings exist. Pain assessment in these patients needs to be simple to understand and use, and requiring minimal or no word or number knowledge, yet demonstrate clinical usefulness and utility with current medications. Methods: This was a cross sectional observational study involving women (n=138) undergoing manual vacuum aspiration of retained products of conception in the gynaecology admission ward at University Teaching Hospital, Lusaka, Zambia. Data was collected using a structured schedule. The first phase aimed to estimate the usefulness of Full Cup Test, Numerical Rating Scale and Faces Pain Scale-Revised in detecting pain. The second phase examined the usefulness of these tools in these patients in detecting change in pain in response to analgesia and the third phase aimed to validate a tool based on ease of understanding and completion and preference. Results: The majority of women (53.6%) were aged between 21and 30 years and the majority (66.7%) had poor education (none or only primary education). The majority of women had severe pain during the procedure. All three tools were useful for detection of pain but however, the faces pain scale revised was the most discriminative. The mean Numerical Rating Scale, Full Cup Test and Faces Pain Scale-Revised scores were statistically correlated (0.67 - 0.94) but there was more correlation between the non-numerical tools. The Faces Pain Scale-Revised was the most preferred tool, was easiest to understand complete. It was able to detect changes in pain levels in relation to analgesia. It was the most acceptable tool for the study population. The current guidelines for intra operative analgesia are inadequate with majority of patients dissatisfied with analgesia provided. None of the analgesic combinations appeared to give significant relief during the procedure. A combination of morphine, ibuprofen and xiii paracetamol gave statistically significant reduction in pain analgesia at 10 minutes and one hour after the manual vacuum aspiration while morphine was shown to have an analgesic effect intra operatively and at 10 minutes by the faces pain scale. Conclusion: The revised faces pain scale (Faces Pain Scale-Revised) is most the most suitable tool for pain assessment in this population. It is clinically useful in both assessing and differentiating changes in pain and is easily understood and useful for patients with low education.