Cardiac Involvment in COVID-19-Related Acute Respiratory Distress Syndrome

The cardiac involvement in Coronavirus disease (COVID-19) is still under evaluation, especially in severe COVID-19-related Acute Respiratory Distress Syndrome (ARDS). The cardiac involvement was assessed by serial troponin levels and echocardiograms in 28 consecutive patients with COVID-19 ARDS consecutively admitted to our Intensive Care Unit from March 1 to March 31. Twenty-eight COVID-19 patients (aged 61.7 ± 10 years, males 79%). The majority was mechanically ventilated (86%) and 4 patients (14%) required veno-venous extracorporeal membrane oxygenation. As of March 31, the Intensive Care Unit mortality rate was 7%, whereas 7 patients were discharged (25%) with a length of stay of 8.2 ±5 days. At echocardiographic assessment on admission, acute core pulmonale was detected in 2 patients who required extracorporeal membrane oxygenation support. Increased systolic arterial pressure was detected in all patients. Increased Troponin T levels were detectable in 11 patients (39%) on admission. At linear regression analysis, troponin T showed a direct relationship with C-reactive Protein (R square: 0.082, F: 5.95, p = 0.017). In conclusions, in COVID-19-related ARDS, increased in Tn levels was common but not associated with alterations in wall motion kinesis, thus suggesting that troponin T elevation is likely to be multifactorial, mainly linked to disease severely (as inferred by the relation between Tn and C-reactive Protein). The increase in systolic pulmonary arterial pressures observed in all patients may be related to hypoxic vasoconstriction. Further studies are needed to confirm our findings in larger cohorts.

Effects of rescue inhaled nitric oxide on right ventricle and pulmonary circulation in severe COVID-related acute respiratory distress syndrome

PURPOSES

To assess the effects of inhaled Nitric Oxide (iNO) on right ventricle dimension and function and systolic pulmonary arterial pressures in severe Acute Respiratory Distress (ARDS) due to Sars-Cov2 (COVID) infection.

MATERIALS AND METHODS

We assessed the effects of iNO on right ventricle dimension and function and systolic pulmonary arterial pressures in 12 consecutive COVID-related ARDS patients by means of serial echocardiographic exams (baseline, 12 and 24 h since iNO start).

RESULTS

Inhaled NO administration did not influence systolic pulmonary arterial pressures nor RV dimension and function. No changes were detectable in ventilatory data with iNO administration. Considering the negligible effect on oxygenation, iNO use was discontinued in all cases.

CONCLUSIONS

In COVID-related severe ARDS iNO administrated as rescue therapy is not able to ameliorate oxygenation nor pulmonary hypertension, as assessed by serial echocardiograms. This finding may be explained by the diffuse loss of hypoxic pulmonary vasoconstriction with increased perfusion around alveolar consolidations which characterizes COVID-related severe ARDS.

Hemodynamic management in brain dead donors

Donor management is the key in the complex donation process, since up to 20% of organs of brain death donors (DBD) are lost due to hemodynamic instability. This challenge is made more difficult due to the lack of strong recommendations on therapies for hemodynamic management in DBDs and more importantly to the epidemiologic changes in these donors who are becoming older and with more comorbidities (marginal donors). In the present manuscript we aimed at summarizing the available evidence on therapeutic strategies for hemodynamic management (focusing on vasoactive drugs) and monitoring (therapeutic goals). Evidence on management in elderly DBDs is also summarized. Donor management continues critical care but with different and specific therapeutic goals since the number of donor goals met is related to the number of organs retrieved and transplanted. Careful monitoring of selected parameters (possibly including serial echocardiography) is the clinical tool able to guarantee the achievement and maintaining of therapeutic goals. Despide worldwide differences, norepinephrine is the vasoactive of choice in most countries but, whenever higher doses (> 0.2 mcg/kg/min) are needed, a second vasoactive drug (vasopressin) is advisable. Hormonal therapy (desmopressin, corticosteroid and thyroid hormone) are suggested in all DBDs independently of hemodynamic instability. In the single patient, therapeutic regimen (imprimis vasoactive drugs) should be chosen also according to the potential organs retrievable (i.e. heart vs liver and kidneys).

Bilirubin in the early course of venovenous extracorporeal membrane oxygenation support for refractory ARDS

Bilirubin is known as a marker of hepatic dysfunction and is incorporated in scoring algorithms to assess prognosis in critically ill patients. No data are so far available on the prognostic role of hepatic dysfunction in patients with severe ARDS on venovenous extracorporeal membrane oxygenation (VV-ECMO) support. In 112 consecutive patients with severe ARDS treated with VV-ECMO, we aimed at assessing whether increased bilirubin during the first 72 h could affect early death. Increased serum bilirubin (≥1.2 mg/dl) was detectable in 29 patients (25.9%) who were older (p = 0.031), exhibited a higher SOFA score (p = 0.006), were more frequently given pre-ECMO muscular blockers (p = 0.001) and supported with ECMO for a longer period (p = 0.024), when compared to patients with normal bilirubin. No difference in in-ICU mortality rate was observed between the two subgroups. In survivors, bilirubin showed a progressive and significant decrease (p = 0.032) during the first 72 h of ECMO support, while it increased in dead patients (p = 0.007).The mortality rate was higher in patients with increased bilirubin at 24, 48 and 72 h after ECMO start in respect to that of patients with normal values. Pre-ECMO increased bilirubin values (≥1.2 mg/dl), being detectable in about one-fourth of the entire population, is not associated with increased in-ICU mortality, while the persistence of increased bilirubin values after 24 h of ECMO start and within the first 3 days identified a subgroup of patients at higher risk of death.

Delayed graft function and perfusion parameters of kidneys from uncontrolled donors after circulatory death

Better preservation and evaluation of kidneys from donors after circulatory death serve to increase the number of kidneys available for transplantation and hypothermic machine perfusion has been shown to decrease ischemia reperfusion injury and delayed graft function. Data on relation between hemodynamic parameters during hypothermic machine perfusion and delayed graft function in kidneys from donors after circulatory death are so far scarce and not univocal. We aimed at assessing whether hemodynamic parameters measured during hypothermic machine perfusion (flow, mean perfusion pressure, and renal resistance) are associated with delayed graft function in 26 kidneys retrieved from uncontrolled donors after circulatory death. In our series, the incidence of delayed graft function was 57.7% (15/26). Recipients who developed delayed graft function had a longer warm ischemic time (p = 0.04). All hemodynamic parameters measured during hypothermic machine perfusion were comparable between recipients with delayed graft function and those without. According to our data, in kidneys from uncontrolled donors after circulatory death, a longer warm ischemic time (that is the overall time of no flow, as the sum of the no-flow and the no-touch period) is associated with delayed graft function. This finding underscores the pivotal role of ischemic injury in terms of absence of flow in affecting graft function. No association was detectable between hemodynamic parameters during hypothermic machine perfusion and the development of delayed graft function in our series.

Right Ventricular Hypertrophy in Refractory Acute Respiratory Distress Syndrome Treated With Venovenous Extracorporeal Membrane Oxygenation Support

OBJECTIVE

In severe acute respiratory distress syndrome (ARDS) treated with extracorporeal membrane oxygenation (ECMO), right ventricular (RV failure) and dilation have been investigated with the use of echocardiography, whereas RV hypertrophy has not been addressed in the literature. The present study assessed the incidence of RV hypertrophy using echocardiography before ECMO treatment and at intensive care unit (ICU) discharge in severe ARDS patients.

DESIGN

Observational, retrospective, single-center study.

SETTING

A single ECMO center.

PARTICIPANTS

The study comprised 46 consecutive patients with severe ARDS.

INTERVENTION

Echocardiographic evaluation and ECMO support.

MEASUREMENTS AND MAIN RESULTS

A dual-lumen cannula was implanted in most patients (38/46 [82.6%]). Before the start of ECMO, RV hypertrophy was present in 28 patients (60.8%) with no significant differences in baseline characteristics between the 2 subgroups. The ICU mortality rate was 30.4% (14/46), with no difference between patients with RV hypertrophy and those without. At ICU discharge, all patients showed RV hypertrophy.

CONCLUSIONS

In severe ARDS treated with ECMO support, RV hypertrophy is a common finding and patients with normal RV wall thickness developed RV hypertrophy after ECMO support. The latter finding may suggest that during ECMO support, the right ventricle still may be subjected to increased afterload. However, additional research should be performed to elucidate the spectrum of mechanism(s) involved in the genesis of RV hypertrophy.

Effect of Respiratory Support Type and Total Duration on Weaning From Venovenous Extracorporeal Membrane Oxygenation in COVID-19 Patients

Background: We evaluated the impact of noninvasive respiratory support (NRS) and invasive mechanical ventilation duration before venovenous extracorporeal membrane oxygenation (VV-ECMO) on weaning from venovenous ECMO and survival. Methods: In a retrospective single-center study, we studied subjects with COVID-19 ARDS treated with VV-ECMO. The subjects were divided and analyzed according to the cut-off of NRS, invasive ventilation, and total duration of respiratory support. Results: We identified a cut-off of NRS duration of 4 days, invasive ventilation duration of 5 days, and total respiratory support duration of 8 days. Weaning from VV-ECMO was observed in 63% (15/24) of subjects with NRS duration ≤ 4 days and in 16% (4/25) of subjects with NRS > 4 days (P = .001), in 50% (17/34) of subjects with invasive ventilation duration ≤ 5 days, in 13% (2/15) of subjects with invasive ventilation duration > 5 days (P = .02), in 68% (13/19) of subjects with total support duration < 8 days, and in 20% (6/30) of subjects with total support duration > 8 days (P = .001). The survival probability at 200 days demonstrated a statistically significant difference in NRS and total support duration comparison (P = .001 and P = .004, respectively). We did not find a statistically significant survival difference according to invasive ventilation duration (P = .13). Conclusions: In our population, the increase in NRS and total support days before ECMO could hamper weaning from VV-ECMO support. However, due to the pandemic, the small sample size, and the lack of precise data on ventilation settings, caution should be exercised in universalizing these results.