Prognostic value of capillary refill time in adult patients: a systematic review with meta-analysis.

PURPOSE: Acute circulatory failure leads to tissue hypoperfusion. Capillary refill time (CRT) has been widely studied, but its predictive value remains debated. We conducted a meta-analysis to assess the ability of CRT to predict death or adverse events in a context at risk or confirmed acute circulatory failure in adults. METHOD: MEDLINE, EMBASE, and Google scholar databases were screened for relevant studies. The pooled area under the ROC curve (AUC ROC), sensitivity, specificity, threshold, and diagnostic odds ratio using a random-effects model were determined. The primary analysis was the ability of abnormal CRT to predict death in patients with acute circulatory failure. Secondary analysis included the ability of CRT to predict death or adverse events in patients at risk or with confirmed acute circulatory failure, the comparison with lactate, and the identification of explanatory factors associated with better accuracy. RESULTS: A total of 60,656 patients in 23 studies were included. Concerning the primary analysis, the pooled AUC ROC of 13 studies was 0.66 (95%CI [0.59; 0.76]), and pooled sensitivity was 54% (95%CI [43; 64]). The pooled specificity was 72% (95%CI [55; 84]). The pooled diagnostic odds ratio was 3.4 (95%CI [1.4; 8.3]). Concerning the secondary analysis, the pooled AUC ROC of 23 studies was 0.69 (95%CI [0.65; 0.74]). The prognostic value of CRT compared to lactate was not significantly different. High-quality CRT was associated with a greater accuracy. CONCLUSION: CRT poorly predicted death and adverse events in patients at risk or established acute circulatory failure. Its accuracy is greater when high-quality CRT measurement is performed.

Hemodynamic Effects of Awake Prone Positioning With COVID-19 Acute Respiratory Failure.

INTRODUCTION: Awake prone positioning (PP) reduces need for intubation for patients with COVID-19 with acute respiratory failure. We investigated the hemodynamic effects of awake PP in non-ventilated subjects with COVID-19 acute respiratory failure. METHODS: We conducted a single-center prospective cohort study. Adult hypoxemic subjects with COVID-19 not requiring invasive mechanical ventilation receiving at least one PP session were included. Hemodynamic assessment was done with transthoracic echocardiography before, during, and after a PP session. RESULTS: Twenty-six subjects were included. We observed a significant and reversible increase in cardiac index (CI) during PP compared to supine position (SP): 3.0 ± 0.8 L/min/m2 in PP, 2.5 ± 0.6 L/min/m2 before PP (SP1), and 2.6 ± 0.5 L/min/m2 after PP (SP2, P < .001). A significant improvement in right ventricular (RV) systolic function was also evidenced during PP: The RV fractional area change was 36 ± 10% in SP1, 46 ± 10% during PP, and 35 ± 8% in SP2 (P < .001). There was no significant difference in PaO2 /FIO2 and breathing frequency. CONCLUSION: CI and RV systolic function are improved by awake PP in non-ventilated subjects with COVID-19 with acute respiratory failure.

Perfusion-based deresuscitation during continuous renal replacement therapy: A before-after pilot study (The early dry Cohort).

BACKGROUND: Active fluid removal has been suggested to improve prognosis following the resolution of acute circulatory failure. We have implemented a routine care protocol to guide fluid removal during continuous renal replacement therapy (CRRT). We designed a before-after pilot study to evaluate the impact of this deresuscitation strategy on the fluid balance. METHODS: Consecutive ICU patients suffering from fluid overload and undergoing CRRT for acute kidney injury underwent a perfusion-based deresuscitation protocol combining a restrictive intake, net ultrafiltration (UFnet) of 2 mL/kg/h, and monitoring of perfusion (early dry group, N = 42) and were compared to a historical group managed according to usual practices (control group, N = 45). The primary outcome was the cumulative fluid balance at day 5 or at discharge. RESULTS: Adjusted cumulative fluid balance was significantly lower in the early dry group (median [IQR]: -7784 [-11,833 to -2933] mL) compared to the control group (-3492 [-9935 to -1736] mL; p = 0.04). The difference was mainly driven by a greater daily UFnet (31 [22-46] mL/kg/day vs. 24 [15-32] mL/kg/day; p = 0.01). There was no significant difference between both groups regarding hemodynamic tolerance. CONCLUSION: Our perfusion-based deresuscitation protocol achieved a greater negative cumulative fluid balance compared to standard practices and was hemodynamically well tolerated.

Structural modeling and environmental regulation of arginine decarboxylase in Synechocystis sp. PCC 6803.

Arginine decarboxylase (ADC) is the first enzyme in the alternative route to putrescine in the polyamine biosynthesis pathway in bacteria and plants. In this study, we have focused on the effects of various types of short-term stresses on the transcript amount and specific activity of Synechocystis sp. PCC 6803 ADC. Our results reveal that the steady-state transcript accumulation and enzyme activity are not connected in a simple manner, since only photoheterotrophy and synergistic salt and high-light stress affected both parameters similarly. Changes in the steady-state ADC mRNA accumulation under the other short-term stress conditions studied had only a small impact on enzyme activity, suggesting post-translational regulation. Based on structural modeling, Synechocystis ADCs have a putative extra domain, which might be involved in the post-translational regulation of ADC activity in Synechocystis. In addition, two symmetric inter-subunit disulfide bonds seem to stabilize the dimeric structure of ADCs. There are two genes coding for ADC and agmatinase, another polyamine pathway enzyme, in Synechocystis genome, while the genes coding for ornithine decarboxylase and for some other enzymes in the polyamine pathway were not identified with homology searches.