Awake prone positioning does not reduce the risk of intubation in COVID-19 treated with high-flow nasal oxygen therapy: a multicenter, adjusted cohort study.

BACKGROUND: Awake prone positioning (awake-PP) in non-intubated coronavirus disease 2019 (COVID-19) patients could avoid endotracheal intubation, reduce the use of critical care resources, and improve survival. We aimed to examine whether the combination of high-flow nasal oxygen therapy (HFNO) with awake-PP prevents the need for intubation when compared to HFNO alone. METHODS: Prospective, multicenter, adjusted observational cohort study in consecutive COVID-19 patients with acute respiratory failure (ARF) receiving respiratory support with HFNO from 12 March to 9 June 2020. Patients were classified as HFNO with or without awake-PP. Logistic models were fitted to predict treatment at baseline using the following variables: age, sex, obesity, non-respiratory Sequential Organ Failure Assessment score, APACHE-II, C-reactive protein, days from symptoms onset to HFNO initiation, respiratory rate, and peripheral oxyhemoglobin saturation. We compared data on demographics, vital signs, laboratory markers, need for invasive mechanical ventilation, days to intubation, ICU length of stay, and ICU mortality between HFNO patients with and without awake-PP. RESULTS: A total of 1076 patients with COVID-19 ARF were admitted, of which 199 patients received HFNO and were analyzed. Fifty-five (27.6%) were pronated during HFNO; 60 (41%) and 22 (40%) patients from the HFNO and HFNO + awake-PP groups were intubated. The use of awake-PP as an adjunctive therapy to HFNO did not reduce the risk of intubation [RR 0.87 (95% CI 0.53-1.43), p = 0.60]. Patients treated with HFNO + awake-PP showed a trend for delay in intubation compared to HFNO alone [median 1 (interquartile range, IQR 1.0-2.5) vs 2 IQR 1.0-3.0] days (p = 0.055), but awake-PP did not affect 28-day mortality [RR 1.04 (95% CI 0.40-2.72), p = 0.92]. CONCLUSION: In patients with COVID-19 ARF treated with HFNO, the use of awake-PP did not reduce the need for intubation or affect mortality.

Safe Reduction in CD4 Cell Count Monitoring in Stable, Virally Suppressed Patients With HIV Infection or HIV/Hepatitis C Virus Coinfection.

BACKGROUND: It has been suggested that routine CD4 cell count monitoring in human immunodeficiency virus (HIV)-monoinfected patients with suppressed viral loads and CD4 cell counts >300 cell/µL could be reduced to annual. HIV/hepatitis C virus (HCV) coinfection is frequent, but evidence supporting similar reductions in CD4 cell count monitoring is lacking for this population. We determined whether CD4 cell count monitoring could be reduced in monoinfected and coinfected patients by estimating the probability of maintaining CD4 cell counts ≥200 cells/µL during continuous HIV suppression. METHODS: The PISCIS Cohort study included data from 14 539 patients aged ≥16 years from 10 hospitals in Catalonia and 2 in the Balearic Islands (Spain) since January 1998. All patients who had at least one period of 6 months of continuous HIV suppression were included in this analysis. Cumulative probabilities with 95% confidence intervals were calculated using the Kaplan-Meier estimator stratified by the initial CD4 cell count at the period of continuous suppression initiation. RESULTS: A total of 8695 patients were included. CD4 cell counts fell to <200 cells/µL in 7.4% patients, and the proportion was lower in patients with an initial count >350 cells/µL (1.8%) and higher in those with an initial count of 200-249 cells/µL (23.1%). CD4 cell counts fell to <200 cells/µL in 5.7% of monoinfected and 11.1% of coinfected patients. Of monoinfected patients with an initial CD4 cell count of 300-349 cells/µL, 95.6% maintained counts ≥200 cells/µL. In the coinfected group with the same initial count, this rate was lower, but 97.6% of coinfected patients with initial counts >350 cells/µL maintained counts ≥200 cells/µL. CONCLUSIONS: From our data, it can be inferred that CD4 cell count monitoring can be safely performed annually in HIV-monoinfected patients with CD4 cell counts >300 cells/µL and HIV/HCV-coinfected patients with counts >350 cells/µL.

Student survey after ten years of continuous blended teaching of echocardiography.

OBJECTIVE: To analyse the impact of 10 years of blended echocardiography teaching. METHODS AND RESULTS: A questionnaire was emailed to all medical doctors who graduated from the blended learning diploma in echocardiography developed by the University of Chile and taught by a team from Chile and Spain. One hundred and forty of the 210 students who graduated from the program between 2011 and 2020 completed the questionnaire: 53.57% were anaesthesiologists, and 26.42% were intensivists. More than 85% of respondents indicated that the online teaching met their expectations, and 70.2% indicated that the hands-on practice fulfilled the stated objectives. In a retrospective analysis using self-reported data, graduates reported that their use of transthoracic and transoesophageal echocardiography has increased from 24.29% to 40.71% and from 13.57% to 27.86%, repectively, after the programme compared to before the programme. They used echocardiography mainly in the perioperative period (56.7%) and during intensive care (32.3%), while only 11% of respondents used it in emergency care units. Nearly all (92.4%) respondents reported that the skills learned was very useful in their professional practice. CONCLUSIONS: Ten years after its launch, the blended learning diploma in echocardiography was well rated by graduate specialists, and is associated with a significant increase in the use of echocardiography in the perioperative period and during intensive care. The main challenges are to establish a longer period of practice and achieve greater implantation in emergency medicine.

Predictive performance of glomerular filtration rate equations based on cystatin C, creatinine and their combination in critically ill patients.

OBJECTIVE: 24-hour urine creatinine clearance (ClCr 24 hours) remains the gold standard for estimating glomerular filtration rate (GFR) in critically ill patients; however, simpler methods are commonly used in clinical practice. Serum creatinine (SCr) is the most frequently used biomarker to estimate GFR; and cystatin C, another biomarker, has been shown to reflect GFR changes earlier than SCr. We assess the performance of equations based on SCr, cystatin C and their combination (SCr-Cyst C) for estimating GFR in critically ill patients. METHODS: Observational unicentric study in a tertiary care hospital. Patients with cystatin C, SCr and ClCr 24 hours measurements in ±2 days admitted to an intensive care unit were included. ClCr 24 hours was considered the reference method. GFR was estimated using SCr-based equations: Chronic Kidney Disease Epidemiology Collaboration based on creatinine (CKD-EPI-Cr) and Cockcroft-Gault (CG); cystatin C-based equations: CKD-EPI-CystC and CAPA; and Cr-CystC-based equations: CKD-EPI-Cr-CystC. Performance of each equation was assessed by calculating bias and precision, and Bland-Altman plots were built. Further analysis was performed with stratified data into CrCl 24 hours <60, 60-130 and ≥130 mL/min/1.73 m2. RESULTS: We included 275 measurements, corresponding to 186 patients. In the overall population, the CKD-EPI-Cr equation showed the lowest bias (2.6) and best precision (33.1). In patients with CrCl 24 hours <60 mL/min/1.73 m2, cystatin-C-based equations showed the lowest bias (<3.0) and CKD-EPI-Cr-CystC was the most accurate (13.6). In the subgroup of 60≤ CrCl 24 hours <130mL/min/1.73 m2, CKD-EPI-Cr-CystC was the most precise (20.9). However, in patients with CrCl 24 hours ≥130mL/min/1.73 m2, cystatin C-based equations underestimated GFR, while CG overestimated it (22.7). CONCLUSIONS: Our study showed no evidence of superiority of any equation over the others for all evaluated parameters: bias, precision and Lin's concordance correlation coefficient. Cystatin C-based equations were less biased in individuals with impaired renal function (GFR <60 mL/min/1.73 m2). CKD-EPI-Cr-CystC performed properly in patients with GFR from 60-130 mL/min/1.73 m2 and none of them were accurate enough in patients ≥130 mL/min/1.73 m2.

Assessment of Individualized Mean Perfusion Pressure Targets for the Prevention of Cardiac Surgery-Associated Acute Kidney Injury-The PrevHemAKI Randomized Controlled Trial.

BACKGROUND: Retrospective studies support that mean perfusion pressure (MPP) deficit in cardiac surgery patients is associated with a higher incidence of acute kidney injury (CS-AKI). The aim of our study was to apply an algorithm based on MPP in the postoperative period to determine whether management with an individualized target reduces the incidence of CS-AKI. METHODS: Randomized controlled trial of patients undergoing cardiac surgery with extracorporeal circulation. Adult patients submitted to valve replacement and/or bypass surgery with a high risk of CS-AKI evaluated by a Leicester score >30 were randomized to follow a target MPP of >75% of the calculated baseline or a standard hemodynamic management during the first postoperative 24 h. RESULTS: Ninety-eight patients with an eGFR of 54 mL/min were included. There were no differences in MAP and MPP in the first 24 h between the randomized groups, although a higher use of noradrenaline was found in the intervention arm (38.78 vs. 63.27, p = 0.026). The percentage of time with MPP < 75% of measured baseline was similar in both groups (10 vs. 12.7%, p = 0.811). MAP during surgery was higher in the intervention group (73 vs. 77 mmHg, p = 0.008). The global incidence of CS-AKI was 36.7%, being 38.6% in the intervention group and 34.6% in the control group (p = 0.40). There were no differences in extrarenal complications between groups as well. CONCLUSION: An individualized hemodynamic management based on MPP compared to standard treatment in cardiac surgery patients was safe but did not reduce the incidence of CS-AKI in our study.

New Insights Into Diuretic Use to Treat Congestion in the ICU: Beyond Furosemide.

Diuretics are commonly used in critically ill patients with acute kidney injury (AKI) and fluid overload in intensive care units (ICU), furosemide being the diuretic of choice in more than 90% of the cases. Current evidence shows that other diuretics with distinct mechanisms of action could be used with good results in patients with selected profiles. From acetazolamide to tolvaptan, we will discuss recent studies and highlight how specific diuretic mechanisms could help to manage different ICU problems, such as loop diuretic resistance, hypernatremia, hyponatremia, or metabolic alkalosis. The current review tries to shed some light on the potential use of non-loop diuretics based on patient profile and give recommendations for loop diuretic treatment performance focused on what the intensivist and critical care nephrologist need to know based on the current evidence.

Severe acute kidney injury in critically ill COVID-19 patients.

BACKGROUND: Acute kidney injury (AKI) is frequent in Coronavirus Infection Disease 2019 (COVID-19) patients. Factors associated with AKI in COVID-19 intensive care unit (ICU) patients and their outcomes have not been previously explored. METHODS: Prospective observational study of COVID-19 patients admitted to the ICUs of the Hospital Clínic of Barcelona (Spain), from March 25th to April 21st, 2020, who developed AKI stage 2 or higher (AKIN classification). The primary goal was to describe the characteristics of moderate-severe AKI of COVID-19 patients in an ICU context. As a secondary goal, we aimed to find independent predictors of AKI progression, Renal Replacement Therapy (RRT) requirement and mortality among these patients. RESULTS: During the study period, 52 out of 237 ICU patients, developed AKIN stage 2 or higher and were included in the study. A Sequential Organ Failure Assessment (SOFA) score at AKI diagnosis of 8 or higher was associated with RRT, OR 5.2, p 0.032. At the time of AKI diagnosis, patients had a worse liver profile and higher inflammation markers than at admission. Fifty per cent of the patients presented AKI progression from AKIN 2 to 3 and 28.85% required RRT. The use of corticosteroids in 69.2% of patients was associated with a reduced requirement of RRT, OR 0.13 (CI 95% 0.02-0.89), p 0.037. AKI was associated with high mortality (50%) and a longer hospital stay, median 35 vs 18 days (p 0.024). CONCLUSIONS: The prevalence of moderate/severe AKI in COVID-19 patients admitted to the ICU is high and has a strong correlation with mortality and length of hospital stay.

Impact of the intensity of intermittent renal replacement therapy in critically ill patients.

BACKGROUND: Intermittent renal replacement therapy (IRRT) is prescribed across intensive care units (ICU) worldwide. While research regarding the prescribed dialysis dose has not yielded results concerning mortality, it is still unknown whether the same applies to the actual delivered dose. METHODS: We retrospectively analyzed two different cohorts of patients (562 IRRT sessions) who were admitted to the intensive care units at Hospital Clínic of Barcelona and required renal replacement therapy with IRRT. The first cohort included patients with acute kidney injury (AKI) (n = 42) and the second included patients already on chronic hemodialysis (CKD 5D) (n = 47). Only patients who had at least 3 recorded hemodialysis sessions in the ICU and with no previous continuous renal replacement therapy (CRRT) were included. The achieved dose was measured as Kt (L) by ionic dialysance and the primary endpoint was 90-day mortality. RESULTS: Ninety-day mortality was 40.5% (n = 17) in the AKI cohort and 23.9% (n = 11) in the CKD 5D cohort with mean Kt of 43 ± 8.27 L and 47 ± 9.65 L respectively. Kt dose of IRRT was associated with 90-day mortality in the AKI cohort in a multivariate surveillance analysis adjusted for confounding factors (HR 0.935 [0.88-0.99], p = 0.02). Only the Kt dose and age remained statistically associated with the outcome in the AKI cohort. CONCLUSIONS: Delivered dialysis dose as measured by ionic-dialysance Kt may be associated with survival in critically-ill patients with AKI, while it does not seem to affect outcomes in critically-ill CKD 5D patients. This exploratory analysis will need confirmation in larger prospective studies.

The use of beta-adrenergic drugs improves hepatic oxygen metabolism in cirrhotic patients undergoing liver resection.

BACKGROUND & AIMS: Hepatic resection is associated with hemodynamic and oxygen metabolism disturbances of the residual liver resulting from liver regeneration. In underlying liver disease, the remnant liver responds inadequately to increased energy demands leading to a less efficient recovery process. The aim of this study was to assess the effect of vasoactive drugs on hepatic oxygen metabolism and hemodynamics in cirrhotic patients that have undergone liver resection. METHODS: Thirty patients were randomly allocated to receive peri-operatively low doses (4 microg/kg/min) of dopamine (DaG, n=10), dobutamine (DbG, n=10) or saline (CG, n=10). Hepatic hemodynamics, hepatic oxygen metabolism and lactate uptakes were evaluated before drug administration and at the time of abdominal closure. Post-operative liver function and outcome were recorded. RESULTS: The peri-operative use of vasoactive drugs preserved total hepatic blood flow and hepatic compliance, even increasing in patients who received Db, whereas those parameters decreased in CG after liver resection. At this time, oxygen delivery and consumption decreased in CG patients, but were unchanged when vasoactive drugs were used. In all groups, lactate uptake decreased sharply and only DbG showed positive lactate extraction capacity. The peak of post-operative bilirubin, which resumed baseline values more quickly in DbG, inversely correlated with intra-operative hepatic compliance and hepatic oxygen extraction. CONCLUSION: Low doses of vasoactive drugs, especially dobutamine, improved hepatic oxygen supply and uptake preserving immediate function of the remnant cirrhotic liver.

Clinical impact of regional citrate anticoagulation in continuous renal replacement therapy in critically ill patients.

BACKGROUND: Regional citrate anticoagulation (RCA) is being used increasingly in continuous renal replacement therapy (CRRT) as a safer alternative to heparin. However, complex metabolic control to avoid side effects have generated discrepancies about its introduction into everyday practice. We aimed to compare both anticoagulation techniques in terms of efficacy, safety and feasibility. METHODS: Observational retrospective study performed in 3 specialized ICUs in patients receiving CVVHDF with RCA between January 2013 and May 2016. Heparin-treated patients matched by age, sex and disease severity treated in the preceding year were selected as historic controls. Filter lifetime, number of filters used, haemorrhagic complications and metabolic complications were recorded. RESULTS: 54 patients (27 treated with RCA and 27 with heparin) were included in the study. Filter lifetimes in the first 72 hours were 55.1 ± 21.8 hours in the RCA group compared to 38.8 ± 24.8 hours in the heparin group, (p = 0.004). In addition, the number of filters used in the first 72 hours was significantly higher in the heparin group (2.4 ± 1.3 vs. 1.5 ± 0.7; p = 0.004). There was a trend toward a lower incidence of bleeding in the RCA group, with a significantly lower red blood cell transfusion rate (p = 0.027) in the citrate group. No clinically significant metabolic disturbances were observed in the RCA group. Regarding outcomes, there were no significant differences between groups. CONCLUSIONS: These results suggest that the implementation of CVVHDF with RCA using concentrated citrate solutions prolongs filter lifetime, achieves a longer effective hemodiafiltration time and is a safe and feasible method.

Ecocardiografía funcional en la unidad de reanimación como monitor hemodinámico / Functional echocardiography in the intensive care unit as hemodinamyc monitor / Ecocardiografia funcional na unidade de terapia intensiva como monitor hemodinâmico

Resumen: La ecocardiografía es una herramienta que desde hace años se ha introducido en las unidades de reanimación. La ausencia de una formación reglada, la larga curva de aprendizaje y el hecho de que la mayoría de protocolos orientados al estudio de la inestabilidad hemodinámica se basan en un concepto estructural, complican su aplicación rutinaria en un contexto tan complejo. Este artículo pretende dar una visión funcional de la ecocardiografía de manera que, integrándola junto con la clínica y otros sistemas de monitorización, se convierta en una herramienta de monitorización hemodinámica a pie de cama. Mediante el uso de un número limitado de planos explicaremos la valoración de diversas herramientas que nos permiten estimar las variables determinantes de la perfusión (precarga estática y dinámica, función biventricular), que a su vez integradas mediante un mapa mental nos asistirán en la toma de decisiones clínicas.

Abstract: Echocardiography has gained wide acceptance between intensive care physicians during the last fifteen years. The lack of accredited formation, long learning curve and structural orientation of the limited algorithms to study hemodynamic instability hampers its daily use in the intensive care unit. This article aims to explain a functional approach to echocardiography in which it serves as a hemodynamic monitoring tool, useful at the bed site in conjunction with clinical assessment and other monitoring devices. Through a limited number of planes and measurements we will explain how to asses perfusion determinants (static and dynamic preload, biventricular function) and integrate them with a mind map to help everyday decision making in the complex environment of the critical care unit.

Resumo: O ecocardiograma é uma ferramenta que foi introduzida há anos nas unidades de terapia intensiva. A ausência de treinamento formal, a curva de aprendizagem prolongada e o fato de que a maioria dos protocolos orientados ao estudo da instabilidade hemodinâmica são baseados em um conceito estrutural complicam sua aplicação de rotina em um contexto tão complexo. Este artigo tem como objetivo dar uma visão funcional da ecocardiografia de modo que, integrando-a com a clínica e outros sistemas de monitoramento, transforme-se em uma ferramenta de monitoramento hemodinâmico na cabeceira do paciente. Usando um número limitado de imagens e medições explicaremos a valorização de várias ferramentas que nos permitem estimar as variáveis determinantes de perfusão (pré-carga estática e dinâmica, função biventricular), que por sua vez integrados por um mapa mental nos ajudará a tomar decisões clínicas.