Lower middle cerebral artery blood velocity during low-volume high-intensity interval exercise in chronic stroke

High-intensity interval training (HIIE) may present unique challenges to the cerebrovascular system in individuals post-stroke. We hypothesized lower middle cerebral artery blood velocity (MCAv) in individuals post-stroke: 1) during 10 minutes of HIIE, 2) immediately following HIIE, and 3) 30 minutes after HIIE, compared to age- and sex-matched controls (CON). We used a recumbent stepper submaximal exercise test to determine workloads for high-intensity and active recovery. Our low volume HIIE protocol consisted of 1-minute intervals for 10 minutes. During HIIE, we measured MCAv, mean arterial pressure (MAP), heart rate (HR), and end tidal carbon dioxide (PETCO2). We assessed carotid-femoral pulse wave velocity as a measure of arterial stiffness. Fifty participants completed the study (25 post-stroke, 76% ischemic, 32% moderate disability). Individuals post-stroke had lower MCAv during HIIE compared to CON (p = 0.03), which remained 30 minutes after HIIE. Individuals post-stroke had greater arterial stiffness (p = 0.01) which was moderately associated with a smaller MCAv responsiveness during HIIE (r = -0.44). No differences were found for MAP, HR, and PETCO2. This study suggests individuals post-stroke had a lower MCAv during HIIE compared to their peers, which remained during recovery up to 30 minutes. Arterial stiffness may contribute to the lower cerebrovascular responsiveness post-stroke.

Lower dynamic cerebral autoregulation following acute bout of low-volume high-intensity interval exercise in chronic stroke compared to healthy adults

Fluctuating arterial blood pressure during high-intensity interval exercise (HIIE) may challenge dynamic cerebral autoregulation (dCA), specifically after stroke after an injury to the cerebrovasculature. We hypothesized that dCA would be attenuated at rest and during a sit-to-stand transition immediately after and 30 min after HIIE in individuals poststroke compared with age- and sex-matched control subjects (CON). HIIE switched every minute between 70% and 10% estimated maximal watts for 10 min. Mean arterial pressure (MAP) and middle cerebral artery blood velocity (MCAv) were recorded. dCA was quantified during spontaneous fluctuations in MAP and MCAv via transfer function analysis. For sit-to-stand, time delay before an increase in cerebrovascular conductance index (CVCi = MCAv/MAP), rate of regulation, and % change in MCAv and MAP were measured. Twenty-two individuals poststroke (age 60 ± 12 yr, 31 ± 16 mo) and twenty-four CON (age 60 ± 13 yr) completed the study. Very low frequency (VLF) gain (P = 0.02, η2 = 0.18) and normalized gain (P = 0.01, η2 = 0.43) had a group × time interaction, with CON improving after HIIE whereas individuals poststroke did not. Individuals poststroke had lower VLF phase (P = 0.03, η2 = 0.22) after HIIE compared with CON. We found no differences in the sit-to-stand measurement of dCA. Our study showed lower dCA during spontaneous fluctuations in MCAv and MAP following HIIE in individuals poststroke compared with CON, whereas the sit-to-stand response was maintained.NEW & NOTEWORTHY This study provides novel insights into poststroke dynamic cerebral autoregulation (dCA) following an acute bout of high-intensity interval exercise (HIIE). In people after stroke, dCA appears attenuated during spontaneous fluctuations in mean arterial pressure (MAP) and middle cerebral artery blood velocity (MCAv) following HIIE. However, the dCA response during a single sit-to-stand transition after HIIE showed no significant difference from controls. These findings suggest that HIIE may temporarily challenge dCA after exercise in individuals with stroke.

The case for health professional student communication skills training for persons with aphasia

Communication challenges in persons with aphasia may negatively affect their health care. Building effective communication skills is critical for health professional student education, yet communication skills for interacting with persons with aphasia are often not taught or practiced within health care education. A review of the literature found that research is limited but does demonstrate evidence-based training can improve skills for health professional students. Through utilization of workshops, seminars, and standardized patients, medical students and other health professional students can build confidence and skills in successful communication for future encounters with persons with aphasia.

The obesity paradox may not lead to functional gains in stroke patients undergoing acute inpatient rehabilitation

INTRODUCTION

Obesity is a risk factor for many adverse health outcomes. However for some cardiac conditions and cancers, evidence of an "obesity paradox" seems to exist where an elevated body mass index (BMI) is linked to protective effects in mortality and functional outcomes. Within the stroke rehabilitation literature, there are conflicting findings on this phenomenon possibly due to unaccounted for variables, such as comorbid medical conditions.

OBJECTIVE

To investigate the association between BMI and functional gains made in acute inpatient stroke rehabilitation, and the effects of multiple confounding variables.

DESIGN

Retrospective cohort study.

SETTING

Tertiary academic hospital.

PATIENTS

Three hundred ninety-two adults following a recent ischemic (82%) or hemorrhagic (18%) stroke with a mean age 62.9 years.

INTERVENTIONS

Acute inpatient rehabilitation.

MAIN OUTCOME MEASURES

Functional Independence Measure (FIM) score and BMI.

RESULTS

A significant association was found between motor FIM score gains and elevated BMI when BMI was treated as a continuous variable (p < .05). However, this association disappeared when patient factors and comorbid conditions were taken into account and when BMI was conceptualized categorically (underweight [BMI <18.5], normal [BMI 18.5-24.9], overweight [BMI 25.0-29.9], obese [BMI 30.0-39.9], and severely obese [BMI ≥40.0]). Advanced age, higher motor function on admission, and a diagnosis of diabetes were all significantly associated with decreased motor FIM gains.

CONCLUSIONS

The results from this study provide insufficient evidence to support the "obesity paradox" once patient factors and comorbid conditions are taken into account. Diabetes was the single comorbidity tracked that showed a significant association with change in motor function (p = .01). Further studies might explore how the unique interventions of rehabilitation physicians and ancillary health professionals might mitigate the functional debility associated with diabetes and obesity in stroke patients.

Pilot Study to Characterize Middle Cerebral Artery Dynamic Response to an Acute Bout of Moderate Intensity Exercise at 3- and 6-Months Poststroke

Background The primary aim of this study was to characterize the middle cerebral artery blood velocity (MCAv) dynamic response to an acute bout of exercise in humans at 3- and 6-months poststroke. As a secondary objective, we grouped individuals according to the MCAv dynamic response to the exercise bout as responder or nonresponder. We tested whether physical activity, aerobic fitness, and exercise mean arterial blood pressure differed between groups. Methods and Results Transcranial Doppler ultrasound measured MCAv during a 90-second baseline followed by a 6-minute moderate intensity exercise bout. Heart rate, mean arterial blood pressure, and end-tidal CO2 were additional variables of interest. The MCAv dynamic response variables included the following: baseline, time delay, amplitude, and time constant. Linear mixed model revealed no significant differences in our selected outcomes between 3- and 6-months poststroke. Individuals characterized as responders demonstrated a faster time delay, higher amplitude, and reported higher levels of physical activity and aerobic fitness when compared with the nonresponders. No between-group differences were identified for baseline, time constant, or exercise mean arterial blood pressure. In the nonresponders, we observed an immediate rise in MCAv following exercise onset followed by an immediate decline to near baseline values, while the responders showed an exponential rise until steady state was reached. Conclusions The MCAv dynamic response profile has the potential to provide valuable information during an acute exercise bout following stroke. Individuals with a greater MCAv response to the exercise stimulus reported statin use and regular participation in exercise.

Chronic hyperglycemia before acute ischemic stroke impairs the bilateral cerebrovascular response to exercise during the subacute recovery period

BACKGROUND AND PURPOSE

Chronic hyperglycemia contributes to cerebrovascular dysfunction by damaging blood vessels. Poor glucose control has been tied to impairments in cerebral blood flow, which may be particularly detrimental for people recovering from major cerebrovascular events such as acute ischemic stroke. In this secondary analysis, we explore for the first time the connection between chronic hyperglycemia before acute stroke and the cerebrovascular response (CVR) to exercise 3 and 6 month into the subacute recovery period.

METHODS

We recorded middle cerebral artery velocity (MCAv) using transcranial Doppler ultrasound bilaterally at rest and during moderate-intensity exercise in stroke patients at 3 (n = 19) and 6 (n = 12) months post-stroke. We calculated CVR as the difference between MCAv during steady-state exercise and resting MCAv. We obtained hemoglobin A1c levels (HbA1c; a measure of blood glucose over the prior 3 months) from the electronic medical record (EMR) and divided participants by HbA1c greater or less than 7%.

RESULTS

Participants with high HbA1c (>7%) at the time of acute stroke had significantly lower CVR to exercise for both the stroke-affected (p = .009) and non-affected (p = .007) hemispheres at 3 months post-stroke. These differences remained significant at 6 months post-stroke (stroke-affected, p = .008; non-affected, p = .016).

CONCLUSIONS

Patients with chronic hyperglycemia before acute ischemic stroke demonstrated impaired cerebrovascular function during exercise months into the subacute recovery period. These findings highlight the importance of maintaining tight glucose control to reduce morbidity and improve recovery post-stroke and could have implications for understanding cerebrovascular pathophysiology.

Middle cerebral artery velocity dynamic response profile during exercise is attenuated following multiple ischemic strokes: a case report

Blood flow regulation is impaired in people with stroke. However, the time course of change in middle cerebral artery velocity (MCAv) following repeated stroke at rest and during exercise remains unknown. In this case study, we provide novel characterization of the dynamic kinetic MCAv response profile to moderate-intensity exercise before and after repeated ischemic MCA stroke. The initial stroke occurred in the left MCA. At 3 months poststroke, left MCAv amplitude (Amp) was ~50% lower than the right. At the 6-month follow-up visit, MCAv Amp declined in both MCA with the left MCAv Amp ~50% lower than the right MCAv Amp. Following a second right MCA stroke, we report further decline in Amp for the left MCA. At the 3- and 6-month visit following the second stroke, the left MCAv Amp declined further (~10%). The right MCAv Amp dramatically decreased by 81.3% when compared to the initial study visit. The MCAv kinetic analysis revealed a marked impairment in the cerebrovascular response to exercise following stroke. We discuss potential pathophysiological mechanisms contributing to poststroke cerebrovascular dysfunction and the need to test therapeutic interventions (such as exercise) that might attenuate cerebrovascular decline in people following stroke.

Feasibility and trend of pulmonary function in a pilot trial of aerobic walking exercise in non-ambulatory stroke survivors

Background: Lung function is compromised in stroke survivors, which may cause fatigue and exercise intolerance. Furthermore, past studies of aerobic exercise have involved only stroke survivors who could walk independently. Stroke survivors who were unable to walk were not included in the previous research-investigating changes in lung function from walking exercise interventions. In this pilot study, the feasibility and the effect of aerobic walking exercise on lung function was examined in non-ambulatory stroke survivors using a treadmill, bodyweight support system, and a gait training device.Methods: This study was a single group trial. Eight non-ambulatory stroke survivors (five males, mean age 63.3 ± 13.7 years, seven with ischemic stroke) completed a low intensity walking exercise program (30 min/session; three sessions/week for 8 weeks) and lung function test. Before and after the intervention, vital capacity (VC) and forced vital capacity (FVC) using a spirometer were measured according to the guideline from American Thoracic Society/European Respiratory Society.Results: The rates of compliance and attrition were 100% and 10%; respectively, and no adverse events were reported. There were significant differences between pre- and post-intervention assessments in FVC (p = .09), percentage of predicted VC (p = .08), and percentage of predicted FVC (p = .08).Conclusions: In non-ambulatory stroke survivors, aerobic walking exercise is feasible and safe. Also, the results are promising and suggest that aerobic walking exercise may improve lung function; more data are needed.

The Rehabilitation of Patients With Advanced Heart Failure After Left Ventricular Assist Device Placement: A Narrative Review

Because more patients with advanced heart failure are receiving a left ventricular assist device (LVAD) as destination therapy or a bridge to transplantation, there is increasing attention on functional outcomes and quality of life after LVAD implantation. Rehabilitation providers in the acute inpatient rehabilitation setting increasingly will treat patients with an LVAD and should understand the exercise physiology, medical management, rehabilitation considerations, and outcomes after rehabilitation for patients with an LVAD. The purpose of this article is to provide the physiatrist with a comprehensive understanding of the rehabilitation of patients with advanced heart failure and LVAD implantation. Changes in relevant organ system physiology and exercise physiology after LVAD are summarized. Safety of rehabilitation and program considerations for acute inpatient rehabilitation are reviewed. Recommendations for medical management and prevention of secondary complications seen in patients with an LVAD are outlined. A discussion of outcomes after acute inpatient rehabilitation, the dual diagnosis of stroke and LVAD placement, and long-term cognitive, functional, and quality-of-life outcomes after LVAD placement is presented.

Functional Outcomes of an Interdisciplinary Outpatient Rehabilitation Program for Patients with Malignant Brain Tumors

BACKGROUND

Malignant brain tumors cause significant impairments in function because of the nature of the disease. Nevertheless, patients with malignant brain tumors can make functional gains equivalent to those with stroke and traumatic brain injury in the inpatient rehabilitation setting. However, the efficacy of outpatient rehabilitation in this population has received little study.

OBJECTIVE

To determine if an interdisciplinary outpatient rehabilitation program will improve functional outcomes in patients with malignant brain tumors.

DESIGN

Nonrandomized prospective longitudinal study.

SETTING

Six affiliated outpatient sites of one institution.

PATIENTS

Forty-nine adults with malignant brain tumors were enrolled.

METHODS

Patients received interdisciplinary therapy services, with duration determined by the therapist evaluations. The therapists scored the Day Rehabilitation Outcome Scale (DayROS) and Disability Rating Scale (DRS) on admission and discharge. The caregivers filled out the DRS at discharge, 1 month, and 3 months after discharge.

MAIN OUTCOME MEASUREMENTS

The primary study outcome measure was the DayROS, which is a functional measure similar to the Functional Independence Measure. DRS was another functional outcome measure assessing basic self-care, dependence on others, and psychosocial adaptability.

RESULTS

Forty-six of 49 enrolled patients (94%) completed the day rehabilitation program. The average length of stay was 76.9 days. There was a significant improvement in total DayROS (P < .001), mobility (P < .001), Activities of Daily Living ( P < .001), and communication (P < .001) DayROS subscores from admission to discharge. There were no significant changes over time in the DRS scores. Women had higher DayROS gains (P = .003) and better therapist DRS scores from admission to discharge than men (P = .010).

CONCLUSIONS

Patients with malignant brain tumors can make functional gains in an interdisciplinary outpatient rehabilitation program. This level of care should be considered in this patient population.

LEVEL OF EVIDENCE

II.

Rehabilitation referrals and outcomes in the early period after hematopoietic cell transplantation

In a cohort of inpatient hematopoietic cell transplantation (HCT) recipients, we assessed patterns of referral to rehabilitation treatment, functional performance and short-term outcomes in patients who received post-transplant rehabilitation in comparison with those who did not. Among 201 first-time HCT recipients, 53 (26%) were referred to an inpatient rehabilitation provider, had an assessment of functional performance using the Functional Independence Measure scale and underwent rehabilitation treatments to address functional needs. Patients who received rehabilitation therapy were more likely to be females (P=0.02), older than 60 years of age (P=0.0146), employed (P=0.01), have hypertension (P=0.02), peripheral vascular disease (P=0.01) and pre-transplant Karnofsky Performance Score (KPS) <90 (P=0.02). Mean functional performance scores for transfers and ambulation increased significantly in the group with rehabilitation interventions (P=0.0022 and P<0.0001, respectively). There was no difference between the groups that did and did not receive rehabilitation treatments in 30-day re-admission rates. Patients who are 60 years of age or older, with pre-transplant KPS<90, and pre-transplant hypertension were more likely to be referred for rehabilitation treatments in the early period after HCT. Future studies should be designed to determine the optimal timing and cost effectiveness of functional assessment and rehabilitation treatments in this high-risk population.

Quality of life, shoulder range of motion, and spinal accessory nerve status in 5-year survivors of head and neck cancer

OBJECTIVE

To determine the association of neck dissection and radiation treatment for head and neck cancer (HNC) with subsequent shoulder range of motion (ROM) and quality of life (QOL) in 5-year survivors.

DESIGN

A cross-sectional convenience sample.

SETTING

Otolaryngology clinics at tertiary care hospital and Veterans Affairs medical center.

PATIENTS

Five-year, disease-free survivors of HNC.

METHODS

Demographic and cancer treatment information was collected, including type of neck dissection (none, spinal accessory "nerve sparing," and "nerve sacrificing") and radiation. QOL questionnaires were administered, and shoulder ROM was measured.

MAIN OUTCOME MEASUREMENTS

University of Washington Quality of Life (UWQOL), Functional Assessment of Cancer Therapy (FACT) Head and Neck, and Performance Status Scale for Head and Neck. Shoulder ROM measurements included abduction, adduction, flexion, extension, internal and external rotation.

RESULTS

One hundred and five survivors completed QOL surveys; 85 survivors underwent additional shoulder ROM evaluations. The nerve sacrifice group exhibited significantly poorer scores for UWQOL measures of disfigurement, level of activity, recreation and/or entertainment, speech and shoulder disability, and willingness to eat in public, FACT functional well-being, and FACT Head and Neck (P < .05). Shoulder ROM for flexion and abduction was poorest in the nerve sacrifice group (P < .05). Radiation was associated with significantly worse UWQOL swallowing (P < .05), but no other differences were found for QOL or ROM measurements. Decreased QOL scores were associated with decreased shoulder flexion and abduction (P < .05). Survivors with decreased shoulder abduction had significantly (P < .05) worse scores in disfigurement, recreation and/or entertainment, employment, shoulder disability, and FACT emotional well-being.

CONCLUSIONS

Sparing the spinal accessory nerve during neck dissection is associated with significantly less long-term shoulder disability in 5-year survivors of HNC. QOL measures demonstrated the highest level of function in the no dissection group, an intermediate level of functioning with nerve sparing, and poorest function when the nerve is sacrificed. Decreased shoulder flexion and abduction is associated with reduced QOL in long-term survivors of HNC.

The role and efficacy of exercise in persons with cancer

Improvements in cancer screening, diagnosis, and treatment have resulted in an increasing population of cancer survivors with impairments in physical function, cancer-related symptoms, and reduced quality of life. Exercise and physical activity have therapeutic value at multiple points along the cancer disease continuum, spanning disease prevention, treatment, survivorship, prognostic outcomes, and end-of-life issues. Molecular mechanisms for the influence of exercise in persons with cancer include altering tumor initiation pathways and affecting hormonal, inflammatory, immune, and insulin pathways. Physical activity has been found to play a role in the prevention of certain malignancies, including breast, colon, and other cancers. An increasing amount of evidence indicates that physical activity may affect prognostic outcomes in certain cancer diagnoses, especially breast cancer. Structured exercise and physical activity interventions can be helpful in addressing specific survivorship issues, including overall quality of life, cardiorespiratory impairment, cancer-related fatigue, and lymphedema. Exercise also may be helpful during the palliative care phase to alleviate symptoms and increase physical well-being. This article will familiarize physiatrists with the current state of evidence regarding the role and efficacy of exercise in persons with cancer.

North American medical schools' experience with and approaches to the needs of students with physical and sensory disabilities

PURPOSE

To determine the nature and frequency of impairments and related underlying conditions of medical students with physical and sensory disabilities (PSDs), and to assess medical schools' use of relevant publications in setting admission criteria and developing appropriate accommodations.

METHOD

A 25-item survey addressed schools' experiences with students known to have PSDs and their related policies and practices. The survey instrument was directed to student affairs deans at all 163 accredited American and Canadian medical schools. The authors limited the survey to consideration of PSDs, excluding psychiatric, cognitive, and learning disabilities.

RESULTS

Eighty-six schools (52.8%) responded, representing an estimated 83,327 students enrolled between 2001 and 2010. Of these students, 0.56% had PSDs at matriculation and 0.42% at graduation. Although 81% of respondents were familiar with published guidelines for technical standards, 71% used locally derived institutional guidelines for the admission of disabled applicants. The most commonly reported accommodations for students with PSDs included extra time to complete tasks/exams (n = 62), ramps, lifts, or accessible entrances (n = 43), and dictated/audio-recorded lectures (n = 40). All responding schools required students' demonstration of physical examination skills; requirements for other technical skills, with or without accommodations, varied considerably.

CONCLUSIONS

The matriculation and graduation rates of medical students with PSDs remain low. The most frequent accommodations reported were among those required of any academic or clinical setting by the Americans with Disabilities Act. There is a lack of consensus regarding technical standards for admission, suggesting a need to reexamine this critical issue.