Oxygenation and brain performance: a critical relationship
Kingston General Hospital Research Institute
Not only can neurological deficits be acquired from brain disease, but also from other health complications. However, because the underlying problem is centralized elsewhere in the body, the presence of these neurological deficits are often ignored or misunderstood. Dr. Gord Boyd, a clinician-scientist at Kingston Health Sciences Centre, is pioneering the use of Kinarm Labs for identifying and assessing sensorimotor and cognitive deficits caused by non-neurological disease. His research is bringing comprehensive, quantitative neurological assessments to new patient groups and refining treatment strategies.
Dr. Boyd’s first research projects with the Kinarm investigated how poor brain tissue oxygenation (BtO2) during the first 24 hours of critical illness impacts brain function and long-term neurologic health. He is the first to connect low cerebral oxygen levels to an increased risk of developing delirium, a devastating and costly problem for patients in critical care.
His subsequent work with the Kinarm explored the relationship between cerebral oxygenation levels during coronary artery bypass grafting (CABG) surgery and postoperative neurological impairment. His research has begun to shed light on previously obscure connections, helping clinicians to understand patient recovery, and quantifying the neurological effects of cardiac surgery.
Dr. Boyd’s current research focuses on the neurological impacts of kidney disease and kidney dialysis. By using the Kinarm Labs and monitoring blood oxygenation levels, Dr. Boyd and his team of researchers are trying to uncover which form of dialysis – hemodialysis or home dialysis – is less damaging to the patient’s cognitive function. They are also working with Dr. Sam Silver, a nephrologist at KHSC, to study how brain function is affected by acute kidney injury. The Kinarm labs and Kinarm Standard Test suite provides Dr. Boyd’s research with the objective and quantified brain function data needed to test hypotheses and improve patient care.
- Low brain tissue oxygenation (BtO2) during the first 24 hours of critical illness leads to an increased risk of developing delirium (CONFOCAL Research Group, 2017; protocol for larger study in progress)
- Following CABG surgery, patients’ Reverse Visually Guided Reaching Task scores declined in a way that significantly correlated with mean and minimum intraoperative cerebral oxygenation values (Semrau et al, 2018) Further studies are underway.
- Kinarm characterized more patients with Chronic Kidney Disease as impaired, and importantly identified novel perceptual-motor impairments in these patients, when compared to traditional assessments. (Vanderlinden et al, 2021)
- In a limited feasibility study investigating with patients initiating hemodialysis, quantitative deficits identified with Kinarm improved after the initiation of dialysis which is not consistent with prior studies (Vanderlinden et al, 2021)
- Kinarm identified quantifiable neurocognitive impairment in survivors of acute kidney injury. Deficits were noted particularly in attention, visuomotor and executive domains. (Vanderlinden et al, 2021)
Learn more about Dr. Boyd’s research:
Investigating how chronic pain affects the brain
Center for Interdisciplinary Research in Rehabilitation and Social Integration (CIRRIS), Université Laval
Research in the field of chronic pain has revealed that anticipated pain can affect patients’ movement preparation, body perception and kinesthesia. However, the variation in these changes between different pain conditions and the mechanisms that cause them are poorly understood. Dr. Catherine Mercier, a researcher at l’Université Laval, is using the Kinarm to help uncover the mysteries behind this relationship.
Her research with the Kinarm spans numerous forms of chronic pain, such as complex regional pain syndrome (CRPS), fibromyalgia, and spinal cord injury. She explores diverse pain-movement relationships, for instance tonic pain and motor learning, and acute pain and sensorimotor conflict perception. Dr. Mercier’s study on corticospinal excitability before anticipated movement-related pain has demonstrated the protective measures used by individuals for lessening acute pain, a strategy which can lead to the development of chronic pain.
Dr. Mercier’s recent publication using the Kinarm studies how proprioception is altered in CRPS patients. In addition to using Kinarm Standard Tests, her team developed protocols for the Kinarm in which the upper limbs of the patient were replaced by virtual limbs that provide altered visual feedback during movement. Her work found that people with chronic pain perform worse on the Arm Position Matching Task and are less able to consciously identify the alteration in visual feedback from the virtual limb, reflecting a poorer perception of their own movements.
Her current research is investigating whether altered feedback can be used to increase movement and reduce movement-related pain during training in populations with chronic pain, who often exhibit fear-avoidance behavior. Equipped with the data and findings produced from the Kinarm Labs, Mercier’s team has the potential to provide long-lasting pain relief for those who are suffering from a variety of chronic pain issues.
- If individuals learn to move differently as a result of pain, they might retain these tendencies even when they no longer feel any pain (Lamothe et al, 2014)
- Patients with acute pain have greater sensory disturbances in response to sensorimotor conflict (Brun et al, 2017)
- Anticipated pain for a movement increases the corticospinal excitability of muscles playing an antagonistic role in this movement and decreases corticospinal excitability of muscles playing an agonistic role; the anticipation of pain for a given movement leads to slower movement initiation but faster movement execution (Neige et al, 2018)
- Both kinesthesia and body perception are altered in CRPS patients but may not be correlated with one another (Brun et al, 2019)
Learn more about Dr. Mercier’s research: