Research Spotlight

Almutairi, S. M., C. Swank, S. S. Wang-Price, F. Gao and A. Medley (2021). “Walking with and without a robotic exoskeleton in people with incomplete spinal cord injury compared to a typical gait pattern.” NeuroRehabilitation. [Epub ahead of print].

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BACKGROUND: Robotic exoskeleton (RE) enables individuals with lower extremity weakness or paralysis to stand and walk in a stereotypical pattern. OBJECTIVE: Examine whether people with chronic incomplete spinal cord injury (SCI) demonstrate a more typical gait pattern when walking overground in a RE than when walking without. METHODS: Motion analysis system synchronized with a surface electromyographic (EMG) was used to obtain temporospatial gait parameters, lower extremity kinematics, and muscle activity in ambulatory individuals with SCI and healthy adults. RESULTS: Temporospatial parameters and kinematics for participants with SCI (n = 12; age 41.4±12.5 years) with and without RE were significantly different than a typical gait (healthy adults: n = 15; age 26.2±8.3 years). EMG amplitudes during the stance phase of a typical gait were similar to those with SCI with and without RE, except the right rectus femoris (p = 0.005) and left gluteus medius (p = 0.014) when participants with SCI walked with RE. EMG amplitudes of participants with SCI during the swing phase were significantly greater compared to those of a typical gait, except for left medial hamstring with (p = 0.025) and without (p = 0.196) RE. CONCLUSIONS: First-time walking in a RE does not appear to produce a typical gait pattern in people with incomplete SCI.

Tatham, K. C., N. D. Ferguson, Q. Zhou, L. Hand, P. Austin, R. Taneja, A. C. Arroliga, J. F. Sanchez, E. J. Jimenez, B. P. Staub, M. E. Kho, J. G. Domínguez-Cherit, A. Mullaly, Y. M. Arabi and M. O. Meade (2021). “Evolution of practice patterns in the management of acute respiratory distress syndrome: A secondary analysis of two successive randomized controlled trials.” J Crit Care 65: 274-281.

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PURPOSE: We sought to examine changes in acute respiratory distress syndrome (ARDS) management over a 12-year period of two successive randomized trials. METHODS: Analyses included baseline data, from eligible patients, prior to influence of trial protocols, and daily study data, from randomized patients, of variables not determined by trial protocols. Mixed linear regressions examined changes in practice year-on-year. RESULTS: A total of 2376 patients met the inclusion criteria. Over the 12-year period, baseline tidal volume index decreased (9.0 to 7.0 ml/kg, p < 0.001), plateau pressures decreased (30.8 to 29.0 cmH(2)O, p < 0.05), and baseline positive end-expiratory pressures increased (10.8 to 13.2 cmH(2)O, p < 0.001). Volume-controlled ventilation declined from 29.4 to 14.0% (p < 0.01). Use of corticosteroids increased (baseline: 7.7 to 30.3%; on study: 32.6 to 61.2%; both p < 0.001), as did neuromuscular blockade (baseline: 12.3 to 24.5%; on study: 55.5 to 70.0%; both p < 0.01). Inhaled nitric oxide use increased (24.9 to 65.8%, p < 0.05). We observed no significant change in prone positioning (16.2 to 18.9%, p = 0.70). CONCLUSIONS: Clear trends were apparent in tidal volume, airway pressures, ventilator modes, adjuncts and rescue therapies. With the exception of prone positioning, and outside the context of rescue therapy, these trends appear consistent with the evolving literature on ARDS management.

Alam, A., G. P. Milligan and T. Gong (2021). “The dominant left ventricular assist device: lessons from an era.” ESC Heart Fail. [Epub ahead of print].

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The production and distribution of the HeartWare ventricular assist device has come to an abrupt end, but with this end comes the opportunity to reflect upon lessons learned from its lifespan. Running counter to the standard of evidence-based practice, the era of the HeartWare ventricular assist device was marred with fragmented data in relation to its primary counterpart, the HeartMate III. This created an incomplete understanding of devices, limited individualized patient care, and effectively positioned providers to make inferences regarding device superiority. We briefly review pertinent literature on this topic among the most commonly implanted durable devices from the era, detail the inherent limitations of this data, and argue the necessity of randomized clinical trials among novel devices towards the optimization of patient care.

Agarwala, A., N. Bekele, E. Deych, M. W. Rich, A. Hussain, L. K. Jones, A. C. Sturm, K. Aspry, E. Nowak, Z. Ahmad, C. M. Ballantyne and A. C. Goldberg (2021). “Racial Disparities in Modifiable Risk Factors and Statin Usage in Black Patients With Familial Hypercholesterolemia.” J Am Heart Assoc 10(17): e020890.

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Background Black men and women are at higher risk for, and suffer greater morbidity and mortality from, atherosclerotic cardiovascular disease (ASCVD) compared with adults of European Ancestry (EA). Black patients with familial hypercholesterolemia are at particularly high risk for ASCVD complications because of lifelong exposure to elevated levels of low-density-lipoprotein cholesterol. Methods and Results This retrospective study analyzed ASCVD prevalence and risk factors in 808 adults with heterozygous familial hypercholesterolemia from 5 US-based lipid clinics, and compared findings in Black versus EA patients. Multivariate logistic regression models were used to determine the strongest predictors of ASCVD as a function of race. No significant difference was noted in the prevalence of ASCVD in Black versus EA patients with familial hypercholesterolemia (39% versus 32%, respectively; P=0.15). However, Black versus EA patients had significantly greater prevalence of modifiable risk factors, including body mass index (mean, 32±7 kg/m(2) versus 29±6 kg/m(2); P<0.001), hypertension (82% versus 50%; P<0.001), diabetes (39% versus 15%; P<0.001), and current smoking (16% versus 8%; P=0.006). Black versus EA patients also had significantly lower usage of statins (61% versus 73%; P=0.004) and other lipid-lowering agents. In a fully adjusted multivariate model, race was not independently associated with ASCVD (odds ratio, 0.92; 95% CI, 0.60-1.49; P=0.72). Conclusions The strongest predictors of ASCVD in Black patients with familial hypercholesterolemia were hypertension and cigarette smoking. These data support wider usage of statins and other lipid-lowering therapies and greater attention to modifiable risk, specifically blood pressure management and smoking cessation.

Bottiglieri, T., X. Wang, E. Arning, H. Fernandez, A. Wall, G. McKenna, R. Ruiz, N. Onaca, J. Trotter, M. Lawrence, B. Naziruddin, S. K. Asrani and G. Testa (2021). “Longitudinal profiling of plasma and urine metabolites during liver regeneration in living liver donors.” Clin Transplant: e14490.[Epub ahead of print].

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BACKGROUND: Knowledge of metabolic processes affected by major hepatectomy (MHx), and the metabolic pathways involved in liver regeneration and recovery of function, is limited and mainly derived from animal models. Assessment of restoration of hepatic function is essential in human living liver donors (LD). METHODS: We used a targeted metabolomic approach to longitudinally quantify changes in plasma and urine biomarkers from healthy LD. The biomarkers were analyzed before MHx and at scheduled intervals up to 12 months thereafter. RESULTS: Marked changes were found in the concentration of 15 primary and secondary plasma bile acids. Most significant changes occurred 2 days after MHx and persisted for up to 3 months. In addition, there were significant changes in acylcarnitine, phospholipid, and amino acid metabolism. The sum of aromatic amino acids and the Fischer ratio, both metabolic markers of liver damage, and the symmetrically demethylated arginine to arginine ratio, a marker of kidney function, were affected. CONCLUSIONS: This is the first comprehensive longitudinal study investigating metabolic processes during recovery of liver function after MHx in LD. It provides further evidence of full restoration of metabolic processes 3 months after MHx and supports future investigation to understand how metabolic changes affect donors’ hepatic function.