Verification of Maximal Oxygen Uptake in Active Military Personnel During Treadmill Running.

ABSTRACT: Figueiredo, PS, Looney, DP, Pryor, JL, Doughty, EM, McClung, HL, Vangala, SV, Santee, WR, Beidleman, BA, and Potter, AW. Verification of maximal oxygen uptake in active military personnel during treadmill running. J Strength Cond Res 36(4): 1053-1058, 2022-It is unclear whether verification tests are required to confirm "true" maximal oxygen uptake (V̇o2max) in modern warfighter populations. Our study investigated the prevalence of V̇o2max attainment in U.S. Army soldiers performing a traditional incremental running test. In addition, we examined the utility of supramaximal verification testing as well as repeated trials for familiarization for accurate V̇o2max assessment. Sixteen U.S. Army soldiers (1 woman, 15 men; age, 21 ± 2 years; height, 1.73 ± 0.06 m; body mass, 71.6 ± 10.1 kg) completed 2 laboratory visits, each with an incremental running test (modified Astrand protocol) and a verification test (110% maximal incremental test speed) on a motorized treadmill. We evaluated V̇o2max attainment during incremental testing by testing for the definitive V̇O2 plateau using a linear least-squares regression approach. Peak oxygen uptake (V̇o2peak) was considered statistically equivalent between tests if the 90% confidence interval around the mean difference was within ±2.1 ml·kg-1·min-1. Oxygen uptake plateaus were identified in 14 of 16 volunteers for visit 1 (87.5%) and all 16 volunteers for visit 2 (100%). Peak oxygen uptake was not statistically equivalent, apparent from the mean difference in V̇o2peak measures between the incremental test and verification test on visit 1 (2.3 ml·kg-1·min-1, [1.3-3.2]) or visit 2 (1.1 ml·kg-1·min-1 [0.2-2.1]). Interestingly, V̇o2peak was equivalent, apparent from the mean difference in V̇o2peak measures between visits for the incremental tests (0.0 ml·kg-1·min-1 [-0.8 to 0.9]) but not the verification tests (-1.2 ml·kg-1·min-1 [-2.2 to -0.2]). Modern U.S. Army soldiers can attain V̇o2max by performing a modified Astrand treadmill running test. Additional familiarization and verification tests for confirming V̇o2max in healthy active military personnel may be unnecessary.

Safety and clinical outcomes of GreenLight laser prostatectomy in octogenarians.

INTRODUCTION: We evaluated the impact of age on perioperative morbidity and clinical outcomes in patients undergoing GreenLight laser prostatectomy for benign prostatic hyperplasia (BPH). METHODS: We conducted a retrospective study of prospectively collected data from individuals who underwent GreenLight laser prostatectomy from May 2018 to July 2022. Patient demographics and outcome measures were recorded, including indications for the procedure and American Society of Anesthesiology (ASA) scores. All patients had postoperative followup visits at one, three, six, and 12 months. Our evaluation included the International Prostate Symptom Score (IPSS ), quality of life (QoL) assessment, maximum urinary flow rate (Qmax), postvoid residual volume (PVR), and catheter-free status. RESULTS: One-hundred-sixty-eight males who underwent GreenLight laser prostatectomy were included. The non-octogenarian group consisted of 111 patients and the octogenarian group comprised 57 individuals. Based on ASA scores, most octogenarians were deemed high-risk (ASA III: 91.2%), while over half of non-octogenarians were lower-risk (ASA II: 53.2%) (p<0.001). Intraoperative parameters, including operative time, vaporization time, lasing time, and energy did not differ significantly between groups. There was no difference in the proportion of intraoperative complications between non-octogenarians and octogenarians (0.9% vs. 3.5%). Postoperative complications were not statistically significant between the two groups (p=0.608). There was also no observed difference in the proportion of patients requiring readmission (p=0.226) or retreatment (p=1.0). CONCLUSIONS: GreenLight laser prostatectomy is a safe and effective treatment for BPH regardless of age. It provides similar surgical and functional outcomes as younger men while maintaining the QoL of octogenarians.

Safety and efficacy of ambulatory tubeless mini-percutaneous nephrolithotomy in the management of 10-25-mm renal calculi: A retrospective study.

INTRODUCTION: This study aimed to assess the safety and efficacy of ambulatory mini-percutaneous nephrolithotomy (mini-PCNL) in a totally tubeless exit (without a nephrostomy tube or an internal stent) and tubeless exit (without a nephrostomy tube but with an internal stent) for the treatment of renal calculi 10-25 mm in size. METHODS: We conducted a retrospective analysis of patients who underwent mini-PCNL at our institution between September 2018 and September 2022. The study included a cohort of 95 patients diagnosed with renal calculi measuring 10-25 mm. All patients underwent a computed tomography (CT) renal colic scan preoperatively, on postoperative day one (POD 1), and at three-month followup. Patient demographics and outcome parameters were recorded, including stone characteristics, operative time, hospital stay, stone-free rate (SFR), complication rates, and subsequent emergency room (ER) visits. Patients were considered stone-free if they had no fragments or residual fragments measuring <4 mm. RESULTS: The median maximum stone diameter was 16 mm (10-25 mm). Twenty-nine patients (30.5%) had multiple renal calculi. The median operative time was 64 (38-135) minutes. Eighty-six patients (90.5%) underwent a totally tubeless procedure, without a nephrostomy tube or an internal stent. All patients were discharged home on the same operative day with a median hospitalization time of six hours. Seven (7.4%) postoperative ER visits were recorded, and two (2.1%) led to hospital readmission. The frequency of grade I, II, and III Clavien-Dindo complications were 18 (18.9%), one (1.1%), and one (1.1%), respectively. The SFR on POD 1 and three-month followup was 73.7% and 92.6%, respectively. None of the patients in the study required retreatment. CONCLUSIONS: Ambulatory tubeless mini-PCNL is a safe and effective treatment option for 10-25 mm renal stones. Experienced institutions can safely adopt ambulatory mini-PCNL as a treatment option without an increased risk of postoperative complications, ER visits, or hospital readmissions.

Peak performance and cardiometabolic responses of modern US army soldiers during heavy, fatiguing vest-borne load carriage.

INTRODUCTION: Physiological limits imposed by vest-borne loads must be defined for optimal performance monitoring of the modern dismounted warfighter. PURPOSE: To evaluate how weighted vests affect locomotion economy and relative cardiometabolic strain during military load carriage while identifying key physiological predictors of exhaustion limits. METHODS: Fifteen US Army soldiers (4 women, 11 men; age, 26 ± 8 years; height, 173 ± 10 cm; body mass (BM), 79 ± 16 kg) performed four incremental walking tests with different vest loads (0, 22, 44, or 66% BM). We examined the effects of vest-borne loading on peak walking speed, the physiological costs of transport, and relative work intensity. We then sought to determine which of the cardiometabolic indicators (oxygen uptake, heart rate, respiration rate) was most predictive of task failure. RESULTS: Peak walking speed significantly decreased with successively heavier vest loads (p < 0.01). Physiological costs per kilometer walked were significantly higher with added vest loads for each measure (p < 0.05). Relative oxygen uptake and heart rate were significantly higher during the loaded trials than the 0% BM trial (p < 0.01) yet not different from one another (p > 0.07). Conversely, respiration rate was significantly higher with the heavier load in every comparison (p < 0.01). Probability modeling revealed heart rate as the best predictor of task failure (marginal R2, 0.587, conditional R2, 0.791). CONCLUSION: Heavy vest-borne loads cause exceptional losses in performance capabilities and increased physiological strain during walking. Heart rate provides a useful non-invasive indicator of relative intensity and task failure during military load carriage.

Evaluation of the updated definition of early allograft dysfunction in donation after brain death and donation after cardiac death liver allografts.

BACKGROUND: An updated definition of early allograft dysfunction (EAD) was recently validated in a multicenter study of 300 deceased donor liver transplant recipients. This analysis did not differentiate between donation after brain death (DBD) and donation after cardiac death (DCD) allograft recipients. METHODS: We reviewed our prospectively entered database for all DBD (n=377) and DCD (n=38) liver transplantations between January 1, 2006 and October 30, 2011. The incidence of EAD as well as its ability to predict graft failure and survival was compared between DBD and DCD groups. RESULTS: EAD was a valid predictor of both graft and patient survival at six months in DBD allograft recipients, but in DCD allograft recipients there was no significant difference in the rate of graft failure in those with EAD (11.5%) compared with those without EAD (16.7%) (P=0.664) or in the rate of death in recipients with EAD (3.8%) compared with those without EAD (8.3%) (P=0.565). The graft failure rate in the first 6 months in those with international normalized ratio ≥1.6 on day 7 who received a DCD allograft was 37.5% compared with 6.7% for those with international normalized ratio <1.6 on day 7 (P=0.022). CONCLUSIONS: The recently validated definition of EAD is a valid predictor of patient and graft survival in recipients of DBD allografts. On initial assessment, it does not appear to be a useful predictor of patient and graft survival in recipients of DCD allografts, however a study with a larger sample size of DCD allografts is needed to confirm these findings. The high ALT/AST levels in most recipients of DCD livers as well as the predisposition to biliary complications and early cholestasis make these parameters as poor predictors of graft failure. An alternative definition of EAD that gives greater weight to the INR on day 7 may be more relevant in this population.

Assessing the Accuracy, Quality, and Readability of Information Related to the Surgical Management of Benign Prostatic Hyperplasia.

Objectives: To assess the accuracy, quality, and readability of online educational health information in English related to the most common benign prostatic hyperplasia (BPH) guideline-approved surgical treatments. Methods: The terms "benign prostatic hyperplasia," "BPH," and all eight guideline-approved treatment modalities studied, were searched to retrieve the first five relevant websites and first two paid advertised websites related to the surgical treatment options for BPH. These modalities included transurethral resection of the prostate (TURP), GreenLight photovaporization, endoscopic enucleation of the prostate, Rezum, Urolift, Aquablation, open simple prostatectomy, and robotic simple prostatectomy (RSP). All relevant websites were assessed for their accuracy, quality, and readability using standardized scoring systems. Results: The mean accuracy score for each of the treatment modalities were all indicative of good accuracy, with 76%-99% of the information presented as being accurate. The median quality score was statistically different across the eight treatment modalities (p = 0.015). The median readability grade level was statistically different across the eight treatment modalities (p = 0.009). Websites that described TURP (median readability grade level, 9.00 [interquartile range (IQR) 8.00-10.80]) were significantly easier to read than those related to RSP (median readability grade level, 14.35 [IQR, 11.08-16.50]) (p = 0.011). No other statistically significant differences were found within the other treatment modality websites. Conclusions: The majority of websites retrieved were found to be of high accuracy, good quality, and poor readability. Additionally, it was found that none of the retrieved websites included descriptions for all the other included treatment modalities. Given these findings, the authors recommend the development of centralized resources with all guideline-approved treatment modalities and accurate, readable, and high-quality information related to the surgical treatment of BPH.

Modeling the Metabolic Costs of Heavy Military Backpacking.

INTRODUCTION: Existing predictive equations underestimate the metabolic costs of heavy military load carriage. Metabolic costs are specific to each type of military equipment, and backpack loads often impose the most sustained burden on the dismounted warfighter. PURPOSE: This study aimed to develop and validate an equation for estimating metabolic rates during heavy backpacking for the US Army Load Carriage Decision Aid (LCDA), an integrated software mission planning tool. METHODS: Thirty healthy, active military-age adults (3 women, 27 men; age, 25 ± 7 yr; height, 1.74 ± 0.07 m; body mass, 77 ± 15 kg) walked for 6-21 min while carrying backpacks loaded up to 66% body mass at speeds between 0.45 and 1.97 m·s-1. A new predictive model, the LCDA backpacking equation, was developed on metabolic rate data calculated from indirect calorimetry. Model estimation performance was evaluated internally by k-fold cross-validation and externally against seven historical reference data sets. We tested if the 90% confidence interval of the mean paired difference was within equivalence limits equal to 10% of the measured metabolic rate. Estimation accuracy and level of agreement were also evaluated by the bias and concordance correlation coefficient (CCC), respectively. RESULTS: Estimates from the LCDA backpacking equation were statistically equivalent (P < 0.01) to metabolic rates measured in the current study (bias, -0.01 ± 0.62 W·kg-1; CCC, 0.965) and from the seven independent data sets (bias, -0.08 ± 0.59 W·kg-1; CCC, 0.926). CONCLUSIONS: The newly derived LCDA backpacking equation provides close estimates of steady-state metabolic energy expenditure during heavy load carriage. These advances enable further optimization of thermal-work strain monitoring, sports nutrition, and hydration strategies.

Effects of modern military backpack loads on walking speed and cardiometabolic responses of US Army Soldiers.

INTRODUCTION: Military leaders must understand how modern military equipment loads affect trade-offs between movement speed and physiological strain to optimize pacing strategies. PURPOSE: To evaluate the effects of load carried in a recently developed military backpack on the walking speed and cardiometabolic responses of dismounted warfighters. METHODS: Fifteen soldiers (1 woman, 14 men; age, 22 ± 2 years; height, 173 ± 7 cm; body mass (BM), 73 ± 10 kg) completed incremental walking tests with four external load conditions (0, 22, 44, or 66% BM) using the US Army's newest backpack: the Modular Lightweight Load-Carrying Equipment 4000 (MOLLE 4000). Oxygen uptake (V̇O2) and heart rate (HR) were evaluated relative to maximal values (V̇O2max and HRmax respectively). Testing ceased when participants completed the highest tested speed (1.97 m s-1), exceeded a respiratory exchange ratio (RER) of 1.00, or reached volitional exhaustion. RESULTS: Peak speed significantly decreased (p < 0.03) with successively heavier loads (0% BM, 1.95 ± 0.06 m s-1; 22% BM, 1.87 ± 0.10 m s-1; 44% BM, 1.69 ± 0.13 m s-1; 66% BM, 1.48 ± 0.13 m s-1). Peak V̇O2 was significantly lower (p < 0.01) with 0% BM (47 ± 5% V̇O2max) than each load (22% BM, 58 ± 8% V̇O2max; 44% BM, 63 ± 10% V̇O2max; 66% BM, 61 ± 11% V̇O2max). Peak HR was significantly lower (p < 0.01) with 0% BM (71 ± 5% HRmax) versus each load (22% BM, 83 ± 6% HRmax; 44% BM, 87 ± 6% HRmax; 66% BM, 88 ± 6% HRmax). CONCLUSION: Overburdened warfighters suffer severe impairments in walking speed even when carrying recently developed military load carriage equipment. Our results suggest that the relative work intensity of heavy load carriage may be better described when expressed relative to HRmax versus V̇O2max.

Application of Novel 3,4-Dihydroxyphenylalanine-Containing Antimicrobial Polymers for the Prevention of Uropathogen Attachment to Urinary Biomaterials.

Introduction and Objective: Urinary catheters and stents are frequently prone to catheter-associated urinary tract infections (CAUTI) through biofilm formation. Several strategies have been evaluated in search of a stent coating to reliably prevent adherence of bacteria and biofilm. Previous in vivo and in vitro research with methoxylated polyethylene glycol 3,4-dihydroxyphenylalanine (DOPA) copolymer as a candidate coating showed promising results to reduce the bacterial attachment. We aimed to further enhance this antimicrobial activity by adding antimicrobial agents to newly synthesized DOPA-based copolymers. Materials and Methods: Building on our previous experience, novel copolymers were engineered based on DOPA. Quaternary ammonium groups and silver particles were added by cross-linking to increase the antimicrobial activity through both kill-by-contact and planktonic killing. After coating polyurethane sheets and measuring contact angles, all candidate coatings were challenged in vitro with an Escherichia coli culture. The most promising coatings were then further evaluated against a panel of seven clinically relevant uropathogens and planktonic killing, and microbial attachment was determined. Results: Initially, seven coatings were developed, referred to as Surphys 093-099. The most significant increase in contact angle was identified in Surphys-095 and -098. Surphys coatings S-094, S-095, and S-098 were cross-linked with silver and exhibited profound antimicrobial properties when challenged with E. coli. Further testing demonstrated S-095 to have antimicrobial efficacy against gram-positive and gram-negative bacteria at different silver-loading concentrations. The final coating, consisting of a 2 mg/mL solution of S-095 cross-linked with 0.25 mg/mL AgNO3, appeared to be highly bactericidal showing a ≥99.9% bacterial killing effect while remaining below cytotoxicity levels. Conclusions: We were able to engineer DOPA-based copolymers and add quaternary ammonium and silver particles, thus increasing the bactericidal properties of the coating. These coatings have exhibited a biologically significant ability to prevent uropathogens from attaching to biomaterials and represent a realistic opportunity to combat CAUTI.

Multicenter Randomized Controlled Trial to Assess an e-Learning on Acute Burns Management.

An e-learning tutorial was developed to cover the basic aspects of acute burns management. The aim of this study was to provide objective educational evidence supporting the role of an e-learning on acute burns management ("basic burns management" or BBM) when compared with traditional teaching methods when introduced in different medical school settings around the world. A multicenter randomized controlled trial was conducted at the University of Pittsburgh, Peninsula College of Medicine and Dentistry, and St. George's University of London comparing the learning experience of medical students with the BBM e-learning tool (intervention) and a traditional lecture (control). A group of medical students was randomly allocated to the e-learning or lecture arms. Both groups were subjected to a 10-question pre-intervention and post-intervention tests assessing burns knowledge, and were asked to fill out a satisfaction survey. A total of 79 medical students of varying years of study participated. As a whole, students demonstrated a significant gain in knowledge after intervention (overall = 47.6%, P < .001), regardless of medical school year of study or interest in surgery. Participants undertaking the BBM e-learning had a greater exam score improvement and satisfaction compared with the traditional lecture even though they were not statistically significant. BBM e-learning is a free tool that provides comparable acute burn care learning opportunity and satisfaction outcomes to a traditional lecture, allowing convenient and standardized incorporation of burns teaching within an educational setting, regardless of geographical location, level of experience, or interest in surgery.

Hand Surgery Fellowship Selection Criteria: A National Fellowship Director Survey.

BACKGROUND: Candidate characteristics for hand surgery fellowship training remains unknown, as very little data is available in the literature. This study aims to provide information on the criteria that are employed to select candidates for the hand surgery fellowship match. METHODS: A 38-question survey was sent in April 2015 to all Accreditation Council for Graduate Medical Education recognized hand surgery fellowship program directors (n=81) involved in the U.S. match. The survey investigated factors used for the selection of applicants, including medical school, residency training, research experience, fellowship interview, and candidate characteristics. A 5-point Likert scale was used to grade 33 factors from "not at all important" (1) to "essential in making my decision" (5); or for five controversial factors from "very negative impact" (1) to "very positive impact in making my decision" (5). RESULTS: A total of 52% (42 out of 81) of responses were received from hand surgery fellowship program directors. The most important influential factors were interactions with faculty during interview and visit (4.6±0.6), interpersonal skills (4.6±0.5), overall interview performance in the selection process (4.6±0.6), professionalism and ethics (4.6±0.7), and letters of recommendation from hand surgeons (4.5±0.7). Factors that have a negative impact on the selection process include visa requirement (2.1±1.2), graduate of non-plastic surgery residency program (2.4±1.3), and graduate of a foreign medical school (2.4±1.1). CONCLUSIONS: This study provides data on hand surgery fellowship directors' perception on the criteria important for fellowship applicant selection, and showed that interview-related criteria and letters of recommendation are the important factors.

South Asian ethnicity as a risk factor for major adverse cardiovascular events after renal transplantation.

BACKGROUND AND OBJECTIVES: South Asians (SAs) comprise 25% of all Canadian visible minorities. SAs constitute a group at high risk for cardiovascular disease in the general population, but the risk in SA kidney transplant recipients has never been studied. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In a cohort study of 864 kidney recipients transplanted from 1998 to 2007 and followed to June 2009, we identified risk factors including ethnicity associated with major cardiac events (MACEs, a composite of nonfatal myocardial infarction, coronary intervention, and cardiac death) within and beyond 3 months after transplant. Kaplan-Meier methodology and multivariate Cox regression analysis were used to determine risk factors for MACEs. RESULTS: There was no difference among SAs (n = 139), whites (n = 550), blacks (n = 65), or East Asians (n = 110) in baseline risk, including pre-existing cardiac disease. Post-transplant MACE rate in SAs was 4.4/100 patient-years compared with 1.31, 1.16, and 1.61/100 patient-years in whites, blacks, and East Asians, respectively (P < 0.0001 versus each). SA ethnicity independently predicted MACEs along with age, male gender, diabetes, systolic BP, and prior cardiac disease. SAs also experienced more MACEs within 3 months after transplant compared with whites (P < 0.0001), blacks (P = 0.04), and East Asians (P = 0.006). However, graft and patient survival was similar to other groups. CONCLUSIONS: SA ethnicity is an independent risk factor for post-transplant cardiac events. Further study of this high-risk group is warranted.