The Characteristics, Dynamics, and the Risk of Death in COVID-19 Positive Dialysis Patients in London, UK.

Background: Patients on dialysis with frequent comorbidities, advanced age, and frailty, who visit treatment facilities frequently, are perhaps more prone to SARS-CoV-2 infection and related death-the risk factors and dynamics of which are unknown. The aim of this study was to investigate the hospital outcomes in patients on dialysis infected with SARS-CoV-2. Methods: Data on 224 patients on hemodialysis between February 29, 2020 and May 15, 2020 with confirmed SARS-CoV-2 were analyzed for outcomes and potential risk factors for death, using a competing risk-regression model assessed by subdistribution hazards ratio (SHR). Results: Crude data analyses suggest an overall case-fatality ratio of 23% (95% CI, 17% to 28%) overall, but that varies across age groups from 11% (95% CI, 0.9% to 9.2%) in patients ≤50 years old and 32% (95% CI, 17% to 48%) in patients >80 years; with 60% of deaths occurring in the first 15 days and 80% within 21 days, indicating a rapid deterioration toward death after admission. Almost 90% of surviving patients were discharged within 28 days. Death was more likely than hospital discharge in patients who were more frail (WHO performance status, 3-4; SHR, 2.16 [95% CI, 1.25 to 3.74]; P=0.006), had ischemic heart disease (SHR, 2.28 [95% CI, 1.32 to 3.94]; P=0.003), cerebrovascular disease (SHR, 2.11 [95% CI, 1.20 to 3.72]; P=0.01), smoking history (SHR, 2.69 [95% CI, 1.33 to 5.45]; P=0.006), patients who were hospitalized (SHR, 10.26 [95% CI, 3.10 to 33.94]; P<0.001), and patients with high CRP (SHR, 1.35 [95% CI, 1.10 to 1.67]) and a high neutrophil:lymphocyte ratio (SHR, 1.03 [95% CI, 1.01 to 1.04], P<0.001). Our data did not support differences in the risk of death associated with sex, ethnicity, dialysis vintage, or other comorbidities. However, comparison with the entire dialysis population attending these hospitals, in which 13% were affected, revealed that patients who were non-White (62% versus 52% in all patients, P=0.001) and those with diabetes (54% versus 22%, P<0.001) were disproportionately affected. Conclusions: This report discusses the outcomes of a large cohort of patients on dialysis. We found SARS-CoV-2 infection affected more patients with diabetes and those who were non-White, with a high case-fatality ratio, which increased significantly with age, frailty, smoking, increasing CRP, and neutrophil:lymphocyte ratio at presentation.

Continuous Infusion of Low-Dose Iohexol Measures Changing Glomerular Filtration Rate in Critically Ill Patients.

OBJECTIVE: Measurement of changing glomerular filtration rate in acute kidney injury remains problematic. We have previously used a continuous infusion of low-dose Iohexol to measure glomerular filtration rate in stable subjects and postulate that changes greater than 10.3% in critically ill patients indicate acute kidney injury. Our objective is to explore the extent to which continuous infusion of low-dose Iohexol can be a measure of changing glomerular filtration rate during acute kidney injury. DESIGN: Clinical observational exploratory study. SETTING: Adult ICU. PATIENTS: Three patient groups were recruited: nephrectomy group: predictable onset of acute kidney injury and outcome (n = 10); surgery group: predictable onset of acute kidney injury, unpredictable outcome (n = 11); and acute kidney injury group: unpredictable onset of acute kidney injury and outcome (n = 13). INTERVENTIONS: Continuous infusion of low-dose Iohexol was administered for 24-80 hours. Plasma (ClP) and renal (ClR) Iohexol clearances were measured at timed intervals. MEASUREMENTS AND MAIN RESULTS: Kidney Disease: Improved Global Outcomes acute kidney injury criteria were fulfilled in 22 patients (nephrectomy = 5, surgery = 4, and acute kidney injury = 13); continuous infusion of low-dose Iohexol demonstrated acute kidney injury in 29 patients (nephrectomy = 10, surgery = 8, acute kidney injury = 11). Dynamic changes in glomerular filtration rate were tracked in all patients. In the nephrectomy group, ClR decreased by an expected 50% (50.8% ± 11.0%). Agreement between ClP and ClR improved with increasing duration of infusion: bias of ClP versus ClR at 48 hours was -0.1 ± 3.6 mL/min/1.73 m (limits of agreement: -7.2 to 7.1 mL/min/1.73 m). Coefficient of variation of laboratory sample analysis was 2.4%. CONCLUSIONS: Continuous infusion of low-dose Iohexol is accurate and precise when measuring glomerular filtration rate and tracks changes in patients with differing risks of acute kidney injury. Continuous infusion of low-dose Iohexol may provide a useful standard against which to test novel biomarkers for the diagnosis of acute kidney injury.

Effect of admission fascia iliaca compartment blocks on post-operative abbreviated mental test scores in elderly fractured neck of femur patients: a retrospective cohort study.

BACKGROUND: Post-operative cognitive impairment is common in elderly patients following surgery for hip fracture, with undertreated pain being an important etiological factor. Non-opioid based analgesic techniques, such as nerve blocks, may help reduce the risk of cognitive complications. The aim of this study was to investigate whether receiving a fascia iliaca compartment block (FICB) as part of a pre-operative analgesic regime increased the odds of high post-operative abbreviated mental test scores (AMTS) when compared with conventional analgesia without a nerve block. METHODS: A retrospective data analysis of a cohort of 959 patients, aged ≥ 65 years with a diagnosis of hip fracture and admitted to a single hospital over a two-year period was performed. A standardized analgesic regime was used on all patients, and 541/959 (56.4%) of included patients received a FICB. Provision of the FICB was primarily determined by availability of an anesthetist, rather than by patient status and condition. Post-operative cognitive ordinal outcomes were defined by AMTS severity as high (score of ≥9/10), moderate, (score of 7-8) and low (score of ≤6). A multivariable ordinal logistic regression analysis was performed on patient status and clinical care factors, including admission AMTS, age, gender, source of admission, time to surgery, type of anesthesia and ASA score. RESULTS: Admission FICB was associated with higher adjusted odds for a high AMTS (score of ≥9) relative to lower AMTS (score of ≤8) than conventional analgesia only (OR = 1.80, 95% CI 1.27-2.54; p = 0.001). Increasing age, lower AMTS on admission to hospital, and being admitted from a residential or nursing home were associated with worse cognitive outcomes. Mode of anesthesia or surgery did not significantly influence post-operative AMTS. CONCLUSION: Post-operative AMTS is influenced by pre-operative analgesic regimes in elderly patients with hip fracture. Provision of a FICB to patients on arrival to hospital may improve early post-operative cognitive performance in this population.

Hemodynamic Effect of Different Doses of Fluids for a Fluid Challenge: A Quasi-Randomized Controlled Study.

OBJECTIVE: The objectives of this study are to determine what is the minimal volume required to perform an effective fluid challenge and to investigate how different doses of IV fluids in an fluid challenge affect the changes in cardiac output and the proportion of responders and nonresponders. DESIGN: Quasi-randomized controlled trial. SETTING: Cardiothoracic ICU, tertiary university hospital. PATIENTS: Eighty postcardiac surgery patients. INTERVENTION: IV infusion of 1, 2, 3, or 4 mL/Kg (body weight) of crystalloid over 5 minutes. MEASUREMENTS AND MAIN RESULTS: Mean systemic filling pressure measured using the transient stop-flow arm arterial-venous equilibrium pressure, arterial and central venous pressure, cardiac output (LiDCOplus; LiDCO, Cambridge, United Kingdom), and heart rate. The groups were well matched with respect to demographic and baseline physiologic variables. The proportion of responders increased from 20% in the group of 1 mL/kg to 65% in the group of 4 mL/kg (p = 0.04). The predicted minimal volume required for an fluid challenge was between 321 and 509 mL. Only 4 mL/Kg increases transient stop-flow arm arterial-venous equilibrium pressure beyond the limits of precision and was significantly associated with a positive response (odds ratio, 7.73; 95% CI, 1.78-31.04). CONCLUSION: The doses of fluids used for an fluid challenge modify the proportions of responders in postoperative patients. A dose of 4 mL/Kg increases transient stop-flow arm arterial-venous equilibrium pressure and reliably detects responders and nonresponders.

The ventricular ectopic QRS interval (VEQSI): Diagnosis of arrhythmogenic right ventricular cardiomyopathy in patients with incomplete disease expression.

BACKGROUND: The ventricular ectopic QRS interval (VEQSI) has been shown to identify structural heart disease and predict mortality. In arrhythmogenic right ventricular cardiomyopathy (ARVC), early diagnosis is difficult using current methods, and life-threatening arrhythmias are common and difficult to predict. OBJECTIVE: The purpose of this study was to assess the utility of ventricular ectopic indices including VEQSI in ARVC diagnosis. METHODS: We studied 70 patients with ARVC [30 with definite disease (age 47 ± 12 years; 60% male), 40 with incomplete disease expression (age 44 ± 18 years; 44% male)], 116 healthy controls (age 40 ± 15 years; 56% male), and 26 patients with normal heart right ventricular outflow tract (RVOT) ectopy (age 46 ± 17 years; 27% male). The duration of the broadest ventricular ectopic beat during 12-lead Holter monitoring was recorded as VEQSI max. RESULTS: VEQSI max was associated with age and gender, but not with conducted QRS duration. Adjusted VEQSI max was greater in ARVC patients than in control groups. In healthy males (44.5 years), estimated VEQSI max was 163 ms (95% confidence interval [CI] 159-167 ms); in definite ARVC 212 ms (95% CI 206-217 ms); in incompletely expressed ARVC 204 ms (95% CI 199-210 ms); and in normal heart RVOT ectopy 171 ms (95% CI 165-178 ms). VEQSI max >180 ms had 98% sensitivity and specificity for diagnosis of ARVC (area under the curve 0.99, 95% CI 0.980-0.998). In our incompletely expressed ARVC patients, VEQSI max >180 ms identified 88% as affected. CONCLUSION: VEQSI max distinguishes ARVC patients, including those with incomplete disease expression, from healthy controls and patients with normal heart RVOT ectopy.

Incidence and mechanisms of cerebral ischemia after transcatheter aortic valve implantation compared with surgical aortic valve replacement.

BACKGROUND: The most likely mechanisms of neurologic injury after transcatheter aortic valve implantation (TAVI) and aortic valve replacement (AVR) are cerebral embolization and hypoperfusion. We set out to determine potential mechanisms of neurologic injury after TAVI compared with AVR. METHODS: One hundred twenty-seven consecutive high-risk patients with severe aortic stenosis (AS) who underwent TAVI (n = 85) or AVR (n = 42) were studied. Transcranial Doppler ultrasound (TCD), cerebral oximetry, diffusion-weighted magnetic resonance imaging (DW-MRI) (before, 6 days, and 3 months after procedure), and neurocognitive assessment before and at 3 months were performed. RESULTS: Neurologic injury was not significantly different between TAVI and AVR at 1 (1.1% vs 2.2%, p = 0.25) and 3 months (4.7% vs 2.2%, p = 1). At 3 months, overall cognitive score was higher in AVR compared with TAVI when adjusted for baseline score; the estimated difference between groups was 0.63 (95% confidence interval 0.87% to 1.17%; p = 0.02). Cerebral embolic load was 212 (123 to 344) during AVR and 134 (76 to 244) during TAVI (p = 0.07). Cerebral oxygen desaturation during AVR (7.56 ± 2.16) was higher compared with TAVI (5.93 ± 2.47) (p < 0.01). Ischemic lesions measured by DW-MRI occurred in 76% of TAVI and 71% of AVR patients at 6 days (p = 0.69) and 63% and 39% at 3 months (p = 0.11). No significant association was found between cerebral emboli, cerebral oxygen desaturation, brain ischemic lesions, and general cognitive score. CONCLUSIONS: At 3 months follow-up, overall cognitive score was higher in AVR compared with TAVI, adjusted for baseline score. However, there was no difference in cerebral embolic load, ischemic lesions, and oxygen desaturation.