Ethics of research for patients in pain

Uncontrolled pain: a call for better study design

Studies assessing animal pain in veterinary research are often performed primarily for the benefit of animals. Frequently, the goal of these studies is to determine whether the analgesic effect of a novel treatment is clinically meaningful, and therefore has the capacity to improve the welfare of treated animals. To determine the treatment effect of a potential analgesic, control groups are necessary to allow comparison. There are negative control groups (where pain is unattenuated) and positive control groups (where pain is attenuated). Arising out of animal welfare concerns, there is growing reluctance to use negative control groups in pain studies. But for studies where pain is experimentally induced, the absence of a negative control group removes the opportunity to demonstrate that the study methods could differentiate a positive control intervention from doing nothing at all. For studies that are controlled by a single comparison group, the capacity to distinguish treatment effects from experimental noise is more difficult; especially considering that pain studies often involve small sample sizes, small and variable treatment effects, systematic error and use pain assessment measures that are unreliable. Due to these limitations, and with a focus on farm animals, we argue that many pain studies would be enhanced by the simultaneous inclusion of positive and negative control groups. This would help provide study-specific definitions of pain and pain attenuation, thereby permitting more reliable estimates of treatment effects. Adoption of our suggested refinements could improve animal welfare outcomes for millions of animals globally.

[Evidence-based guideline for neonatal pain management in China (2023)]

Pain disrupts neonatal vital signs and internal environment homeostasis and affects the recovery process, and recurrent pain stimulation is one of the important risk factors for neurodevelopmental disorders and some chronic diseases. In order to standardize pain management practice in neonatal wards in China and effectively prevent and reduce the adverse effects of pain on the physical and mental development of neonates, National Clinical Research Center for Child Health and Diseases (Children's Hospital of Chongqing Medical University) convened a multidisciplinary panel to formulate the evidence-based guideline for neonatal pain management in China (2023 edition) following the principles and methods for the guideline development issued by the World Health Organization. Based on the best evidence and expert consensus, this guideline gives 26 recommendations for nine clinical issues, i.e., the classification and definition of neonatal pain, common sources of pain, pain assessment principles, pain assessment methods, analgesic principle, non-pharmaceutical analgesic methods, pharmaceutical analgesic methods, parental participation in pain management, and recording methods for pain management, so as to provide medical staff with guidance and a decision-making basis for neonatal pain assessment and analgesia management.

Efficacy and safety of non-pharmacological interventions for neonatal pain: an overview of systematic reviews

OBJECTIVES

To synthesise current evidence from systematic reviews (SRs) regarding the efficacy and safety of non-pharmacological interventions to prevent and treat pain in newborn infants.

DESIGN

Overview of SRs.

DATA SOURCES

We searched PubMed, Embase, Cochrane Library, Web of Science, CINAHL, Chinese National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), Wanfang Database, Chinese Science and Technology Periodical Database (VIP) and Google Scholar to identify all relevant SRs published in the last 5 years.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included SRs that evaluated the efficacy and safety of non-pharmacological interventions for neonatal pain.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted the data, assessed the methodological quality using a Measurement Tool to Assess Systematic Reviews (AMSTAR) 2 and graded the evidence quality with the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

RESULTS

A total of 29 SRs were included in this overview, of which 28 focused on procedural pain and only 1 focused on postoperative pain. Based on AMSTAR 2, seven reviews were found to be of 'high quality', eight of 'moderate quality', five of 'low quality' and nine of 'critically low quality'. The GRADE results suggested that facilitated tucking, kangaroo care, sweet solutions, familiar odour or combined non-pharmacological interventions, such as a combination of sucrose and non-nutritive sucking, were effective and safe in reducing pain from medical procedures in neonates. However, sucrose alone was less effective than local anaesthesia or a combination of the two during circumcision.

CONCLUSIONS

Facilitated tucking, small volumes of sweet solutions, kangaroo care and familiar odour were recommended. Scientific implementation strategies should be developed to promote the clinical use of these effective non-pharmacological interventions. Meanwhile, further rigorous trials and SRs are needed to identify the best non-pharmacological approaches for pain from common surgery and illnesses in neonates.

PROSPERO REGISTRATION NUMBER

CRD42021292583.