scholarly journals Novel Clinimetric Toolset to Quantify the Stability of Blood Pressure and Its Application to Evaluate Cardiovascular Function After Spinal Cord Injury

2021 ◽  
Vol 1 ◽  
Author(s):  
Samineh Mesbah ◽  
Bonnie Legg Ditterline ◽  
Siqi Wang ◽  
Samuel Wu ◽  
Joseph Weir ◽  
...  

Profound dysfunction of the cardiovascular system occurs after spinal cord injury (SCI), which is a leading cause of mortality in this population. Most individuals with chronic SCI experience transient episodes of hypotensive and hypertensive blood pressure in response to daily life activities. There are currently limited tools available to evaluate the stability of blood pressure with respect to a reference range. The aim of this study was to develop a clinimetric toolset for accurately quantifying stability of the blood pressure measurements and taking into consideration the complex dynamics of blood pressure variability among individuals with SCI. The proposed toolset is based on distribution of the blood pressure data points within and outside of the clinically recommended range. This toolset consists of six outcome measures including 1) total deviation of the 90% of the blood pressure data points from the center of the target range (115 mmHg); 2) The area under the cumulative distribution curve starting from the percentage of blood pressure measurements within the range, and the percentage of values within symmetrically expanded boundary ranges, above and below the target range; 3) the slope of the cumulative distribution curve that is calculated by fitting an exponential cumulative distribution function and the natural logarithm of its rate parameter; 4) its x- and 5) y-axis intercepts; and 6) the fitting error. These outcome measures were validated using blood pressure measurements recorded during cardiovascular perturbation tests and prolonged monitoring period from individuals with chronic SCI and non-injured controls. The statistical analysis based on the effect size and intra-class correlation coefficient, demonstrated that the proposed outcome measures fulfill reliability, responsiveness and discrimination criteria. The novel methodology proposed in this study is reliable and effective for evaluating the stability of continuous blood pressure in individuals with chronic spinal cord injury.

2021 ◽  
Vol 10 (7) ◽  
pp. 1417
Author(s):  
Rikke Middelhede Hansen ◽  
Klaus Krogh ◽  
Joan Sundby ◽  
Andrei Krassioukov ◽  
Ellen Merete Hagen

Postprandial hypotension (PPH) is defined as a fall of ≥20 mmHg in systolic blood pressure (SBP) or a SBP of <90 mmHg after having been >100 mmHg before the meal within two hours after a meal. The prevalence of PPH among persons with spinal cord injury (SCI) is unknown. Ambulatory blood pressure measurement was performed in 158 persons with SCI, 109 men, median age was 59.1 years (min.:13.2; max.: 86.2). In total, 78 persons (49.4%) had PPH after 114 out of 449 meals (25.4%). The median change in SBP during PPH was −28 mmHg (min.: −87; max.: −15 mmHg) and 96% of the PPH episodes were asymptomatic. The occurrence of PPH was correlated to older age (p = 0.001), level of injury (p = 0.023), and complete SCI (p = 0.000), but not, gender or time since injury. Further studies are needed to elucidate if PPH contributes to the increased cardiovascular mortality in the SCI population.


Spinal Cord ◽  
2021 ◽  
Author(s):  
Helge Kasch ◽  
Uffe Schou Løve ◽  
Anette Bach Jønsson ◽  
Kaare Eg Severinsen ◽  
Marc Possover ◽  
...  

Abstract Study design 1-year prospective RCT. Objective Examine the effect of implantable pulse generator and low-frequency stimulation of the pelvic nerves using laparoscopic implantation of neuroprosthesis (LION) compared with neuromuscular electrical stimulation (NMES) in SCI. Methods Inclusion criteria: traumatic spinal cord injury (SCI), age 18–55 years, neurological level-of-injury Th4–L1, time-since-injury >1 year, and AIS-grades A–B. Participants were randomized to (A) LION procedure or (B) control group receiving NMES. Primary outcome measure: Walking Index for Spinal Cord Injury (WISCI-II), which is a SCI specific outcome measure assessing ability to ambulate. Secondary outcome measures: Spinal Cord Independence Measure III (SCIM III), Patient Global Impression of Change (PGIC), Penn Spasm Frequency Scale (PSFS), severity of spasticity measured by Numeric Rating Scale (NRS-11); International Spinal Cord Injury data sets-Quality of Life Basic Data Set (QoLBDS), and Brief Pain Inventory (BPI). Results Seventeen SCI individuals, AIS grade A, neurological level ranging from Th4–L1, were randomized to the study. One individual was excluded prior to intervention. Eight participants (7 males) with a mean age (SD) of 35.5 (12.4) years were allocated to the LION procedure, 8 participants (7 males) with age of 38.8 (15.1) years were allocated to NMES. Significantly, 5 LION group participants gained 1 point on the WISCI II scale, (p < 0.013; Fisher´s exact test). WISCI II scale score did not change in controls. No significant changes were observed in the secondary outcome measures. Conclusion The LION procedure is a promising new treatment for individuals with SCI with significant one-year improvement in walking ability.


1991 ◽  
Vol 80 (3) ◽  
pp. 271-276 ◽  
Author(s):  
Henry Krum ◽  
William J. Louis ◽  
Douglas J. Brown ◽  
Graham P. Jackman ◽  
Laurence G. Howes

1. Measurement of blood pressure and heart rate over a 24 h period was peformed in 10 quadriplegic spinal cord injury patients and 10 immobilized, neurologically intact orthopaedic subjects by using the Spacelabs 90207 automated ambulatory monitoring system. 2. Systolic and diastolic blood pressure fell significantly at night in orthopaedic subjects but not in quadriplegic patients, and night-time blood pressures were similar in both groups. 3. Cumulative summation of differences from a reference value (cusum analysis) confirmed a markedly diminished diurnal blood pressure variation in the quadriplegic patients. 4. These findings could not be accounted for on the basis of blood pressure variations during chronic postural change. 5. Heart rate fell significantly at night in both groups. 6. The findings suggest that the increase in blood pressure during waking hours in neurologically intact subjects is a consequence of a diurnal variation in sympathetic activity (absent in quadriplegic patients with sympathetic decentralization) which is independent of changes in physical activity.


Diagnostics ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1321
Author(s):  
Joo-Hyun Kee ◽  
Jun-Hyeong Han ◽  
Chang-Won Moon ◽  
Kang Hee Cho

Patients with a spinal cord injury (SCI) frequently experience sudden falls in blood pressure during postural change. Few studies have investigated whether the measurement of blood flow velocity within vessels can reflect brain perfusion during postural change. By performing carotid duplex ultrasonography (CDU), we investigated changes in cerebral blood flow (CBF) during postural changes in patients with a cervical SCI, determined the correlation of CBF change with presyncopal symptoms, and investigated factors affecting cerebral autoregulation. We reviewed the medical records of 100 patients with a cervical SCI who underwent CDU. The differences between the systolic blood pressure, diastolic blood pressure, and CBF volume in the supine posture and after 5 min at 50° tilt were evaluated. Presyncopal symptoms occurred when the blood flow volume of the internal carotid artery decreased by ≥21% after tilt. In the group that had orthostatic hypotension and severe CBF decrease during tilt, the body mass index and physical and functional scores were lower than in other groups, and the proportion of patients with a severe SCI was high. The higher the SCI severity and the lower the functional score, the higher the possibility of cerebral autoregulation failure. CBF should be assessed by conducting CDU in patients with a high-level SCI.


2002 ◽  
Vol 93 (6) ◽  
pp. 1966-1972 ◽  
Author(s):  
Maria T. E. Hopman ◽  
Jan T. Groothuis ◽  
Marcel Flendrie ◽  
Karin H. L. Gerrits ◽  
Sibrand Houtman

The purpose of the present study was to determine the effect of a spinal cord injury (SCI) on resting vascular resistance in paralyzed legs in humans. To accomplish this goal, we measured blood pressure and resting flow above and below the lesion (by using venous occlusion plethysmography) in 11 patients with SCI and in 10 healthy controls (C). Relative vascular resistance was calculated as mean arterial pressure in millimeters of mercury divided by the arterial blood flow in milliliters per minute per 100 milliliters of tissue. Arterial blood flow in the sympathetically deprived and paralyzed legs of SCI was significantly lower than leg blood flow in C. Because mean arterial pressure showed no differences between both groups, leg vascular resistance in SCI was significantly higher than in C. Within the SCI group, arterial blood flow was significantly higher and vascular resistance significantly lower in the arms than in the legs. To distinguish between the effect of loss of central neural control vs. deconditioning, a group of nine SCI patients was trained for 6 wk and showed a 30% increase in leg blood flow with unchanged blood pressure levels, indicating a marked reduction in vascular resistance. In conclusion, vascular resistance is increased in the paralyzed legs of individuals with SCI and is reversible by training.


2012 ◽  
Vol 18 (1) ◽  
pp. 1-14 ◽  
Author(s):  
John Steeves ◽  
Daniel Lammertse ◽  
John Kramer ◽  
Naomi Kleitman,* ◽  
Sukhvinder Kalsi-Ryan ◽  
...  

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