The PIUO Study

Optimizing the Management of Pain and Irritability in Children with Severe Neurological Impairment

What is this study about?

The purpose of this project is to develop, test, and disseminate a new approach to reducing and resolving pain in children with Severe Neurological Impairments (SNI). It focuses on the problem of ongoing, unexplained, and difficult-to-treat pain and irritability that many children with SNI, and their families, experience.


How is the study designed?

Over four years, 120 kids aged 6 months to 18 years will be studied at four sites across Canada:

·     BC Children's Hospital, Vancouver

·     Alberta Children's Hospital, Calgary

·     Hospital for Sick Children, Toronto

·     Children's Hospital of Eastern Ontario, Ottawa



Pain we cannot explain

Children with SNI are non-verbal, non-mobile and have limited cognitive abilities. Pain is the most common symptom reported by caregivers of these children; however, pain is notoriously difficult to identify, and therefore treat, in non-verbal children because their signals of distress are ambiguous and hard to decode. Parents and healthcare providers rely on interpretation of pain-like behaviours (vocalizations, grimacing, arching and muscle tightening, etc.) to determine the presence of pain. These signs are challenging to evaluate and the pain cannot always be attributed to a specific cause. Moreover, in children with complex neurological conditions, pain-like behaviours are not always due to disease or injury, but instead may be due to generalized irritability of the central nervous system.

We call this phenomenon Pain and Irritability of Unknown Origin - PIUO

Lacking an explanation for the source leaves clinicians unable to treat the pain and increases a parent’s obstacles in providing care. As clinicians and researchers who care for these children, our goal is to improve the assessment and treatment of pain and irritability. However, we have learned that even experienced physicians do not always agree on a common approach for the medical treatment of kids suffering from PIUO. Physicians rely on their expertise and past experiences meaning the path one specialist follows may be different from another and results in repeated tests or interventions if children seek help from multiple health care specialists.

We have developed a new approach to evaluating and treating PIUO that we call the PIUO Pathway. The PIUO Pathway focuses on eliminating undiagnosed but treatable sources of PIUO. It targets PIUO in an intentional, focused, timely sequential order of standardized steps with physician and dedicated nurse support. The PIUO Pathway is implemented by clinicians with expertise in treating pain in children. A key element is the ongoing and frequent contact between families and clinicians to coordinate tests and treatments along the PIUO Pathway and to monitor results.


Impact of the PIUO Study

Our goal is to improve PIUO management beyond what has been accomplished by the child's usual clinical teams. In a small pilot study of the PIUO Pathway we reduced or resolved pain and irritability for 63% of participants. The primary outcome of our study is better pain control for non-verbal children with SNI. We also hope to decrease pain severity for our participants, improve family quality of life and ensure that the PIUO Pathway can be easily implemented by clinicians in the future.

In the long term we hope that this research will result in:

  • New practice guidelines that should achieve early detection, effective interventions (personalized medicine) and ultimately prevention for persistent complex pain in a highly vulnerable population of children
  • Training that will accelerate increased consistency and confidence of community practitioners in treating PIUO
  • Ability to help children across the province to obtain care in the community, which means fewer clinic visits and emergency room visits, fewer days for inpatient care and thereby overall savings to the health care system

If this study confirms that the PIUO Pathway can be used to improve PIUO in children with SNI, the results will create the first-ever systemized practice guideline to treat pain in this challenging and vulnerable population based on a solid evidence base. Ultimately, such guidelines will streamline pain management for this population and improve children and their families’ well-being. The results will inform families, front-line clinicians, and researchers about better ways to address one of the most troubling symptoms occurring in children with complex, incurable conditions.

Contact: Anne-Mette Hermansen