Citations

Abstract Many survivors from severe coronavirus disease 2019 (COVID‐19) suffer from persistent dyspnea and fatigue long after resolution of the active infection. In a cohort of 21 consecutive severe post‐COVID‐19 survivors admitted to an inpatient rehabilitation hospital, 16 (76%) of them had at least one sonographic abnormality of diaphragm muscle structure or function. This corresponded to a significant reduction in diaphragm muscle contractility as represented by thickening ratio (muscle thickness at maximal inspiration/end‐expiration) for the post‐COVID‐19 compared to non‐COVID‐19 cohorts. These findings may shed new light on neuromuscular respiratory dysfunction as a contributor to prolonged functional impairments after hospitalization for post‐COVID‐19.

AbstractIn 2018, the American College of Sports Medicine (ACSM) reconvened an international, multi‐disciplinary group of professionals to review pertinent published literature on exercise for people with cancer. The 2018 roundtable resulted in the publication of three articles in 2019. The three articles serve as an important update to the original ACSM Roundtable on Cancer, which convened in 2010. Although the focus of the three 2019 articles is on exercise, which is only one part of comprehensive cancer rehabilitation, the evidence presented in the 2019 ACSM articles has direct implications for physiatrists and other rehabilitation professionals who care for people with cancer. As such, the narrative review presented here has two primary objectives. First, we summarize the evidence within the three ACSM articles and interpret it within a familiar rehabilitation framework, namely the Dietz model of Cancer Rehabilitation, in order to facilitate implementation broadly within rehabilitation practice. Second, via expert consensus, we have tabulated relevant exercise recommendations for specific cancer populations at different points in the cancer care continuum and translated them into text, tables, and figures for ease of reference. Notably, the authors of this article are members of the Cancer Rehabilitation Physician Consortium (CRPC), a group of physicians who subspecialize in cancer rehabilitation medicine (CRM).

Local warming in human skin elicits a biphasic vasodilation with a local sensory nerve component (initial peak) and nitric oxide mediated plateau. Though microvascular dysfunction in type 2 diabetes mellitus (T2DM) is well known, effects at the neural level of control in individuals with well managed T2DM are less understood. We tested the hypothesis that local sensory nerve contributions to vasodilation are less in T2DM compared to healthy controls (C). We measured skin blood flow using laser‐Doppler flowmetry (LDF) and arterial pressure using Finometer in T2DM and C subjects at baseline and during 35 minutes of local warming (LW) of the skin to 42 °C. Two LDF sites received Ringers via microdialysis throughout LW; one site was pretreated with local lidocaine (LIDO) to block local sensory innervation. Maximum cutaneous vascular conductance (CVC) was evaluated using microdialysis of nitroprusside. In preliminary studies (N = 4 T2DM, 6 C), CVC during the initial peak at the untreated site was decreased in T2DM (73 ± 4 vs. C: 85 ± 5 % max; P = 0.05), but was not different at the LIDO site (T2DM: 54 ± 9 vs. C: 66 ± 6 % max; P > 0.05). The difference between sites (sensory nerve contribution) was similar between groups (T2DM: 19 ± 7 vs. C: 18 ± 7 % max; P > 0.05), and was lower with LIDO than was previously shown with local EMLA. Our results suggest a non‐neural component which is decreased in T2DM. Supported by NIH HL73884 and CTSA UL1 RR024150.

Thermoregulatory increases in skin blood flow in humans are brought about by a combination of cutaneous vasodilation and increased cardiac output. As such, whole body heating (WBH) in humans is associated with increased heart rate and decreased blood pressure compared to normothermic baseline conditions. We hypothesized that the tachycardia and hypotension associated with WBH in resting humans would be diminished in individuals with type 2 diabetes mellitus (T2DM) compared to controls (C) of similar age due to altered autonomic control of cardiac function in T2DM. We measured heart rate (HR; ECG) and beat‐to‐beat blood pressure (Finometer) in 6 individuals with T2DM and 6 control subjects at baseline and during WBH with a water‐perfused suit. Resting HR and blood pressure were similar in C vs. T2DM (HR: C: 59 ± 2; T2DM: 62 ± 4, P > 0.05; MAP: C: 93 ± 7; T2DM: 95 ± 7, P > 0.05). During body heating, heart rate increased significantly in both groups; at peak of WBH, HR was 91 ± 4 in C and 92 ± 1 in T2DM. This represented a change of 32 ± 3 in C and 27 ± 3 in T2DM (P > 0.05). Our preliminary data suggest a similar increase in HR and decrease in BP during body heating in T2DM when compared with C. This may have implications for clinical applications in the treatment and management of T2DM, particularly with regard to heat exposure and/or exercise.

Dehydration in humans decreases orthostatic tolerance and alters sympathetic neural control of the circulation, but the mechanisms involved are unclear. Our goal was to evaluate the role of angiotensin II (AngII) in altering the sympathetic control mechanisms in dehydration. We hypothesized that dehydration would increase resting muscle sympathetic nerve activity (MSNA) and increase sensitivity of baroreflex control of MSNA and that these changes are mediated in part by AngII via AT1 receptors. We measured resting MSNA and baroreflex control of MSNA in healthy young adults under two conditions: euhydration and dehydration after 24 hr fluid restriction. We continuously measured heart rate (ECG), beat‐to‐beat blood pressure (Finometer), central venous pressure (peripherally inserted central catheter) and MSNA (peroneal microneurography) in both conditions. In each condition, measurements were taken before and after 50 mg losartan (AT1 antagonist). Dehydration was associated with a ~52 % increase in resting MSNA, but losartan did not consistently influence resting MSNA. Contrary to our hypothesis, baroreflex sensitivity increased ~39 % following losartan administration during dehydration. Our results confirm the sympathoexcitatory influence of dehydration, but the role of AngII in this process requires further evaluation. Supported by AHA 0750036Z and NIH CTSA UL1‐RR24150.

In humans, sympathetic nerves in the skin provide tonic vasoconstrictor innervation. Although neural changes in type 2 diabetes mellitus (T2DM) are well recognized, it is unclear to what extent the activity of these vasoconstrictor nerves is altered in individuals with relatively uncomplicated T2DM. We tested the hypothesis that skin sympathetic nerve activity (SSNA) is decreased at rest in individuals with T2DM compared to healthy controls (C), and that the increase in SSNA with whole body cooling is smaller in T2DM than in C. We measured SSNA using microneurography, skin blood flow using laser‐Doppler flowmetry (LDF), and arterial pressure using Finometer in T2DM and C subjects at baseline and during 3–5 minutes of whole body cooling. LDF was measured on the foot at the site of innervation of the measured SSNA signal. Whole body cooling was followed by 35 min of local warming of the skin to 42°C to determine maximum cutaneous vascular conductance. In preliminary studies (N=3 per group), SSNA at baseline (T2DM: 22 ± 8 vs. C: 30 ± 1 bursts/min) and during whole body cooling (T2DM: 28 ± 11 vs. C: 43 ± 2 bursts/min; deltas: T2DM: + 6 ± 3 vs. C: +13 ± 1 bursts/min) tended to be lower in T2DM compared to C. Our data suggest that changes in control of SSNA in T2DM contribute to altered thermoregulatory responses in these individuals. Supported by NIH R01 HL73884 and CTSA UL1‐RR24150.

A key step in the lysosomal degradation of membrane proteins is sorting into the Multivesicular Body (MVB), a process wherein a region of the endosomal membrane buds into the lumen of the endosome to form an intraluminal vesicle (ILV). This sorting process is mediated by Endosomal Sorting Complexes Required for Transport (ESCRT‐0, I, II and III). Ubiquitination of MVB cargo and recognition of Ub‐cargo by ESCRT‐0, I and II permit entry into the MVB pathway; however, Ub is typically removed from the MVB cargo prior to cargo inclusion into the ILV. The coordination of deubiquination of MVB cargo with ESCRT‐III disassembly and ILV formation are not clear. Bro1 appears to play a critical role in coordinating cargo de‐ubiquitination and ILV formation through interactions with ESCRT machinery, the Ub peptidase, Doa4, ubiquitin‐modified cargo, and regulation of the ESCRT‐III‐associated AAA ATPase Vps4. These data suggest that members of the Bro1 family may be similarly impacting ESCRT‐dependent processes in a number of contexts. Grant Funding Source : NIH R01 GM07302

e18634 Background: Informed patients have better health outcomes. In a study of 1,057 patient encounters with 3,552 clinical decisions, only 9% resulted in informed medical decisions.The complexity of treatments and patients' limitations in health literacy (especially common in underserved communities) make it difficult for patients to engage in SDM. In 2017, A Breath of Hope Lung Foundation introduced An Animated Patient’s Guide to Lung Cancer (APG), an online resource aimed at improving patient knowledge. Methods: APG consists of animations, expert FAQ videos, slide shows, infographics, patient-experience videos, knowledge-assessment tools, and learner feedback. Video views, duration of use, and learner responses to multiple-choice questions on the APG website were collected for 33 months – through August 2020. Total APG views, most frequently viewed animations and expert videos were monitored on the website and on YouTube, to measure learner responses to outcome-based questions, and learner intent-to-implement changes. Results: 212,336 total views: 142,998 unique visitors: 59% from U.S. and 41% from 50 other countries. Unique U.S. visitors: 43,872 patients, 16,030 caregivers, and 7,593 health providers. 94% reported they will ‘use new information to better self-manage their lung cancer’ (n = 277); 98% ‘will discuss information learned with their doctor’ (n = 455), and 93% ‘plan to discuss treatment options with their doctor’ (n = 272). Conclusions: Multimedia ‘animated’ formats of learning tailored to the needs and learning styles of lung cancer patients provides effective learning, informed patients, increased management skills, and improved engagement in shared decision making.

Aims To describe the risk of periprosthetic joint infection (PJI) and reoperation in patients who have an acute, traumatic wound dehiscence following total knee arthroplasty (TKA). Methods From January 2002 to December 2018, 16,134 primary TKAs were performed at a single institution. A total of 26 patients (0.1%) had a traumatic wound dehiscence within the first 30 days. Mean age was 68 years (44 to 87), 38% (n = 10) were female, and mean BMI was 34 kg/m2 (23 to 48). Median time to dehiscence was 13 days (interquartile range (IQR) 4 to 15). The dehiscence resulted from a fall in 22 patients and sudden flexion after staple removal in four. The arthrotomy was also disrupted in 58% (n = 15), including a complete extensor mechanism disruption in four knees. An irrigation and debridement with component retention (IDCR) was performed within 48 hours in 19 of 26 knees and two-thirds were discharged on antibiotic therapy. The mean follow-up was six years (2 to 15). The association of wound dehiscence and the risk of developing a PJI was analyzed. Results Patients who sustained a traumatic wound dehiscence had a 6.5-fold increase in the risk of PJI (95% confidence interval (CI) 1.6 to 26.2; p = 0.008). With the small number of PJIs, no variables were found to be significant risk factors. However, there were no PJIs in any of the patients who were treated with IDCR and a course of antibiotics. Three knees required reoperation including one two-stage exchange for PJI, one repeat IDCR for PJI, and one revision for aseptic loosening of the tibial component. Conclusion Despite having a traumatic wound dehiscence, the risk of PJI was low, but much higher than experienced in all other TKAs during the same period. We recommend urgent IDCR and a course of postoperative antibiotics to decrease the risk of PJI. A traumatic wound dehiscence increases risk of PJI by 6.5-fold. Cite this article: Bone Joint J 2021;103-B(6 Supple A):191–195.