Exploration of surgical blood pressure management and expected motor recovery in individuals with traumatic spinal cord injury

Abstract

Study design Retrospective analysis. Objective To assess the impact of mean arterial blood pressure (MAP) during surgical intervention for spinal cord injury (SCI) on motor recovery. Setting Level-one Trauma Hospital and Acute Rehabilitation Hospital in San Jose, CA, USA. Methods Twenty-five individuals with traumatic SCI who received surgical and acute rehabilitation care at a level-one trauma center were included in this study. The Surgical Information System captured intraoperative MAPs on a minute-byminute basis and exposure was quantified at sequential thresholds from 50 to 104 mmHg. Change in International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) motor score was calculated based on physiatry evaluations at the earliest postoperative time and at discharge from acute rehabilitation. Linear regression models were used to estimate the rate of recovery across the entire MAP range. Results An exploratory analysis revealed that increased time within an intraoperative MAP range (70-94 mmHg) was associated with ISNCSCI motor score improvement. A significant regression equation was found for the MAP range 70-94 mmHg (F[1, 23] = 4.65, r 2 = 0.168, p = 0.042). ISNCSCI motor scores increased 0.036 for each minute of exposure to the MAP range 70-94 mmHg during the operative procedure; this represents a significant correlation between intraoperative time with MAP 70-94 and subsequent motor recovery. Blood pressure exposures above or below this range did not display a positive association with motor recovery. Conclusions Hypertension as well as hypotension during surgery may impact the trajectory of recovery in individuals with SCI, and there may be a direct relationship between intraoperative MAP and motor recovery.

Diagnostic blood RNA profiles for human acute spinal cord injury

“…TRACK-SCI (Transforming Research and Clinical Knowledge-SCI) is a multicenter prospective clinical study focused on acute critical care variables (e.g., magnetic resonance imaging, multiple physiological variables, time to surgery) and blood transcriptomics as indices of severity and predictors of outcome ( Dhall et al, 2018 ; Ehsanian et al, 2020 ; McCoy et al, 2019 ; Talbott et al, 2015 ). SCI has a profound impact on circulating WBCs, inducing peripheral inflammation and WBC phenotypic changes in a dynamic cascade that is likely to reflect the biological features of the evolving CNS lesion ( Bloom et al, 2020 ; Marbourg et al, 2017 ).…”

Expert-augmented automated machine learning optimizes hemodynamic predictors of spinal cord injury outcome

“…mean, standard deviation, skew, and kurtosis) derived from timeseries data capturing heart rate, systolic blood pressure, diastolic blood pressure, and mean arterial pressure (MAP) during SCI surgery. As intraoperative hypertension and hypertension have been shown to be detrimental to SCI outcome [ 26 , 27 ], we also calculated the time each patient spent outside of previously-established upper (104 mmHg) or lower (76 mmHg) MAP thresholds during surgery ( time_MAP_Avg_above_104 and time_MAP_Avg_below_76 , respectively) [ 28 ]. We defined the prediction target as whether the patient’s ASIA Impairment Scale (AIS) score, a common SCI outcome assessment [ 29 ], improved between time of hospital admission and time of hospital discharge.…”

“…Previous blood pressure management studies have primarily focused on hypotension as a contributor to worse patient outcome [ 58 – 60 ] despite the increased risk of cardiovascular and cerebrovascular complications as a result of hypertension [ 61 ]. Notably, the importance of perioperative hypertension for SCI outcome has been observed both clinically and preclinically [ 26 – 28 , 62 ]; this is the first analysis to suggest that hypertension is more predictive of worse outcome than hypotension, thus proposing that careful MAP management should strive to avoid hypertension while minimizing hypotension. Future prospective clinical studies should extend the verifiability of the findings throughout broader SCI patient care such as during treatment in the emergency room and intensive care unit.…”

Expert-integrated automated machine learning uncovers hemodynamic predictors in spinal cord injury

“…mean, standard deviation, skew, and kurtosis) derived from timeseries data capturing heart rate, systolic blood pressure, diastolic blood pressure, and mean arterial pressure (MAP) during SCI surgery. As intraoperative hypertension and hypertension have been shown to be detrimental to SCI outcome 26,27 , we also calculated the time each patient spent outside of previously-established upper (104 mmHg) or lower (76 mmHg) MAP thresholds during surgery ( time_MAP_Avg_above_104 and time_MAP_Avg_below_76 , respectively) 28 . We defined the prediction target as whether the patient’s ASIA Impairment Scale (AIS) score, a common SCI outcome assessment 29 , improved between time of hospital admission and time of hospital discharge.…”

“…Previous blood pressure management studies have primarily focused on hypotension as a contributor to worse patient outcome 58–60 despite the increased risk of cardiovascular and cerebrovascular complications as a result of hypertension 61 . Notably, the importance of perioperative hypertension for SCI outcome has been observed both clinically and preclinically 26–28,62 ; this is the first analysis to suggest that hypertension is more predictive of worse outcome than hypotension, thus proposing that careful MAP management should strive to avoid hypertension while minimizing hypotension. Future prospective clinical studies should extend the verifiability of the findings throughout broader SCI patient care such as during treatment in the emergency room and intensive care unit.…”