Mara, Kristin C.

Females demonstrate less robust Frank‐Starling mechanism with respect to cardiac preload than males at rest. We asked whether this phenomenon would also affect cardiac performance during exercise. We hypothesized that stroke volume (SV) response to exercise would be more limited in deconditioned females such that cardiac output would be mainly rate dependent, compared with males. We conducted a chart audit of clinical exercise tests performed by adolescents with chronic fatigue. Oxygen uptake () was measured breath‐by‐breath at rest and during cycle ergometry, while cardiac output was measured by acetylene rebreathing at rest plus 2‐3 subthreshold workloads. SV response was analyzed in two ways: after normalization for body surface area (SV index, SVI) and as percentage change from resting values. Among 304 adolescents (78% females) with chronic fatigue, 189 (80%) of 236 females and 52 (76%) of 68 males were deconditioned (peakO2 <90% predicted). Heart rate trajectory during exercise was steeper for unfit than fit females, 70 vs 61 beat·min−1 per L·min−1 , (P=.003); but not for males, 47 vs 42 beat·min−1 per L·min−1 (P=.23). The highest measured SVI did not differ between unfit vs fit females (42.8 vs 41.5 mL·m−2, P=.39) while fit males showed larger SV during exercise than their unfit peers (highest SVI 55.9 vs 48.0 mL·m−2, P=.014). Both qualitative and quantitative sex differences exist in SV responses to exercise among chronically fatigued adolescents, suggesting volume loading may be more efficacious in girls.

Background: Total knee arthroplasty (TKA) with a rotating-hinge prosthesis is considered a salvage procedure. While excellent immediate stability is achieved, the historically high failure rate has tempered its use. The goal of this study was to determine clinical outcomes, radiographic results, and survivorship after TKA with contemporary rotating-hinge components. Methods: We identified 408 consecutive TKAs performed with rotating-hinge components for nononcologic indications from 2002 to 2012 at a single academic institution. Two hundred and sixty-four knees (65%) had rotating-hinge TKA components implanted for aseptic etiologies, while 144 knees (35%) were managed with the components in 2-stage reimplantation following infection. Rotating-hinge TKA implants were used for complex primary procedures in 74 knees (18%) and as a revision construct in 334 knees (82%). Clinical outcomes were assessed with the Knee Society scoring system, survivorship analyses, and cumulative incidence of revision. The mean age of the patients at the time of the index arthroplasty was 69 years, and the mean duration of follow-up was 4 years (range, 2 to 12 years). Results: At the most recent follow-up, the mean Knee Society knee score had increased from 51 points preoperatively to 81 points (p < 0.0001), and the mean Knee Society functional score had increased from 26 to 36 points (p < 0.0001). At a mean of 4 years, loosening of components was observed in 13 (3.7%) of 349 knees. At the most recent follow-up, 59 revision procedures and 25 reoperations had been performed. The cumulative incidence of any revision was 9.7% at 2 years and 22.5% at 10 years. The cumulative incidence of revision for aseptic loosening was 1.7% at 2 years and 4.5% at 10 years. Metaphyseal cones were used in 114 knees (28%). Survivorship analysis revealed a trend toward a lower risk of revision (hazard ratio [HR] = 0.69; 95% confidence interval [CI] = 0.39 to 1.22; p = 0.20) and reoperation (HR = 0.51; 95% CI = 0.22 to 1.19; p = 0.12) in patients with metaphyseal cones, despite their use in the most severe of bone defects. Conclusions: Contemporary rotating-hinge TKA implants had a low 10-year cumulative incidence of revision for aseptic loosening of 4.5%. Greater use of metaphyseal fixation has aided this improvement. Patients can expect substantial improvements in clinical outcomes with this revision strategy. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Background and objectives Prior work has suggested a higher risk of hypertension in kidney stone formers but lacked disease validation and adjustment for potential confounders. Certain types of stone formers may also be at higher risk of hypertension. Design, setting, participants, & measurements In our study, incident symptomatic stone formers in Olmsted County from 2000 to 2011 were manually validated by chart review and age and sex matched to Olmsted County controls. We followed up patients through November 20, 2015. Hypertension was also validated by manual chart review, and the risk of hypertension in stone formers compared with controls was assessed both univariately and after adjusting for comorbidities. The risk of hypertension among different subtypes of stone formers was also evaluated. Results Among 3023 coded stone formers from 2000 to 2011, a total of 1515 were validated and matched to 1515 controls (mean age was 45 years old, and 56% were men). After excluding those with baseline hypertension (20% of stone formers and 18% of controls), 154 stone formers and 110 controls developed hypertension. Median follow-up time was 7.8 years in stone formers and 9.6 years in controls. Stone formers were found to have a higher risk of hypertension compared with controls (hazard ratio, 1.50; 95% confidence interval, 1.18 to 1.92), even after adjusting for age, sex, body mass index, serum creatinine, CKD, diabetes, gout, coronary artery disease, dyslipidemia, tobacco use, and alcohol abuse (hazard ratio, 1.58; 95% confidence interval, 1.12 to 2.21). Results were similar after excluding patients who were ever on a thiazide diuretic (hazard ratio, 1.65; 95% confidence interval, 1.16 to 2.38). Stone composition, radiographic stone burden, number of subsequent stone events, and stone removal surgeries were not associated with hypertension ( P >0.05 for all). Conclusions The risk of hypertension was higher after the first symptomatic kidney stone event. However, kidney stone severity, type, and treatment did not associate with hypertension.

Objectives This study evaluated our experience after implementing a pelvic floor rehabilitation program including behavioral modification, biofeedback, and vaginal electrogalvanic stimulation (EGS). Methods This prospective cohort study evaluated outcomes of patients with pelvic floor dysfunction (urinary or defecatory dysfunction, pelvic pain/dyspareunia) who underwent pelvic floor rehabilitation. Patients received 4 to 7 sessions (1 every 2 weeks) including biofeedback and concluded with 30 minutes of vaginal EGS. Surveys assessed subjective changes in symptoms; success was evaluated using a 10-point visual analog scale (VAS) at the final session (10 = most successful). Paired comparisons of responses at baseline and final treatment were evaluated. Results Ninety-four patients were followed up through therapy completion. Treatment indications included urinary (89.4%), defecatory (33.0%), and pelvic pain or dyspareunia (30.9%); 44.7% of patients had a combination of indications. Among women with urinary symptoms, the percentage reporting leakage decreased from 92.9% to 79.3% (P = 0.001), leakage at least daily decreased from 69.0% to 39.5% (P < 0.001), daily urgency with leakage decreased from 42.7% to 19.5% (P = 0.001), daily urgency without leakage decreased from 41.5% to 18.3% (P < 0.001), and median VAS rating (0 = not at all, 10 = a great deal) of daily life interference decreased from 5 to 1.5 (P < 0.001). The median success ratings were 8, 8, and 7 for treatment of urinary symptoms, pelvic pain/dyspareunia, and bowel symptoms, respectively. Conclusions An aggressive pelvic rehabilitation program including biofeedback with vaginal EGS had a high rate of self-reported subjective success and satisfaction and should be considered a nonsurgical treatment option in patients with pelvic floor dysfunction.

Objectives Rectovaginal fistulae (RVF) often represent surgical challenges, and treatment must be individualized. We describe outcomes after primary surgical repair stratified by fistula etiology and surgical approach. Methods This retrospective cohort study included women who underwent surgical management of RVF at a tertiary care center between July 1, 2001 and December 31, 2013. Cases were stratified according to the following etiology: cancer (RVF-C), inflammatory bowel disease or infectious (RVF-I), and other (RVF-O). Patients with prior surgical treatment of RVF were excluded. Surgical approaches included local (seton, plug), transvaginal or endorectal, abdominal, diversion alone, or definitive (completion proctocolectomy with permanent colostomy or pelvic exenteration). Recurrence-free survival was estimated using the Kaplan-Meier method, and comparisons between subgroups were evaluated based on fitting Cox proportional hazards models. Censoring occurred at last relevant clinical follow-up. Factors contributing to recurrence-free survival were evaluated including age, body mass index, smoking status, fistula etiology, ileostomy, and surgical approach. Results During the study period, 107 women underwent surgical repair of RVF. The most common fistula etiology was RVF-I (54.2%), followed by RVF-O (23.4%), and RVF-C (22.4%). Ninety-four women underwent fistula repair by the local (29.9%), transvaginal/endorectal (25.2%), abdominal approach (19.6%), or diversion alone (13.1%), whereas 13 underwent definitive surgery (12.2%). Recurrence-free survival was significantly different depending on surgical approach ( P < 0.001), but not etiology ( P = 0.71). Recurrence-free survival (95% confidence interval) at 1 year after surgery was 35.2% (21.8%–56.9%) for the local approach, 55.6% (37.0%–83.3%) for the transvaginal or endorectal approach, 95% (85.9%–100%) for the abdominal approach, and 33.3% (15%–74.2%) for those with diversion only. Conclusions Recurrence rates after RVF repair are high and did not differ by fistula etiology. Abdominal repair of RVF had significantly fewer recurrences.

Background. Obesity is a significant issue in the critically ill population. There is little evidence directing the dosing of venous thromboembolism (VTE) prophylaxis within this population. We aimed to determine whether obesity predisposes medical intensive care unit patients to venous thromboembolism despite standard chemoprophylaxis with 5000 international units of subcutaneous heparin three times daily.Results. We found a 60% increased risk of venous thromboembolism in the body mass index (BMI) ≥ 30 kg/m2group compared to the BMI < 30 kg/m2group; however, this difference did not reach statistical significance. After further utilizing our risk model, neither obesity nor mechanical ventilation reached statistical significance; however, vasopressor administration was associated with a threefold risk.Conclusions. We can conclude that obesity did increase the rate of VTE, but not to a statistically significant level in this single center medical intensive care unit population.

Biomechanical evaluation of the subsynovial connective tissue (SSCT) provides insight into the causes of carpal tunnel syndrome. Studies of carpal tunnel mechanics have been performed using fresh-frozen cadaver tissue. Freezing can affect mechanical properties of some tissues, but its effect on SSCT is unknown. A total of 16 rabbit paws were harvested from eight New Zealand rabbits and subjected to mechanical testing consisting of three repeated tendon excursions in sets of three different excursion magnitudes. One paw from each animal was unfrozen. The contralateral paw was frozen and thawed before testing. Force, energy and stiffness of the first cycle of each set were evaluated, as were ratios of the second to first cycle for each parameter. Two-factor ANOVA with repeated measures over both factors was performed. No significant interactions between factors were found. There were no significant differences between fresh and frozen paws for any parameters, though there were significant differences between excursion amplitudes. The damage threshold was not different between fresh and frozen paws. This study demonstrated that freezing rabbit subsynovial connective tissue does not significantly change its mechanical properties. The same may be true for human cadaver tissues. Results of cadaver mechanical testing may not be influenced by this preservation technique.