ECMO for COVID-19 patients in Europe and Israel

Since March 15th, 2020, 177 centres from Europe and Israel have joined the study, routinely reporting on the ECMO support they provide to COVID-19 patients. The mean annual number of cases treated with ECMO in the participating centres before the pandemic (2019) was 55. The number of COVID-19 patients has increased rapidly each week reaching 1531 treated patients as of September 14th. The greatest number of cases has been reported from France (n = 385), UK (n = 193), Germany (n = 176), Spain (n = 166), and Italy (n = 136) .The mean age of treated patients was 52.6 years (range 16–80), 79% were male. The ECMO configuration used was VV in 91% of cases, VA in 5% and other in 4%. The mean PaO2 before ECMO implantation was 65 mmHg. The mean duration of ECMO support thus far has been 18 days and the mean ICU length of stay of these patients was 33 days. As of the 14th September, overall 841 patients have been weaned from ECMO support, 601 died during ECMO support, 71 died after withdrawal of ECMO, 79 are still receiving ECMO support and for 10 patients status n.a. . Our preliminary data suggest that patients placed on ECMO with severe refractory respiratory or cardiac failure secondary to COVID-19 have a reasonable (55%) chance of survival. Further extensive data analysis is expected to provide invaluable information on the demographics, severity of illness, indications and different ECMO management strategies in these patients

Prevention and treatment of acute kidney injury after cardiac surgery

Acute kidney injury (AKI) occurs frequently after cardiac surgery and is independently associated with increased mortality. The main cause of AKI in these patients is renal ischemia. However, data on the renal oxygenation, defined as the renal oxygen supply/demand relationship are lacking in clinical AKI, and the effects of various pharmacological interventions on renal oxygenation are not known. Patients and methods: The effects of mannitol (n=10) and dopamine (n=12) on renal blood flow (RBF), glomerular filtration rate (GFR) and renal oxygenation were analysed in post-cardiac surgery patients using the renal vein thermodilution technique. Furthermore, RBF, GFR and renal oxygenation were studied in patients with AKI (n=12) and compared to postoperative patients with no renal impairment (n=37). Finally, the effects of norepinephrine-induced changes in mean arterial pressure (MAP) on renal variables were analysed in AKI patients (n=12) with vasodilatory shock. Results: Mannitol increased GFR and the renal oxygen demand (RVO2), while it had no effect on RBF. Mannitol, thus, pharmacologically improved the renal function at the cost of an impaired renal oxygenation. In contrast, dopamine redistributed blood flow to the kidney and increased RBF, but had no effect on GFR or RVO2. Consequently, dopamine improved renal oxygenation. AKI patients had a 40% lower RBF and a 60 % lower net-sodium reabsorption and GFR compared to control patients. However, contrary to previous hypothesis, this decrease in reabsorptive workload was not accompanied with a decrease in RVO2. Thus, renal oxygenation was severely impaired in AKI. The high RVO2 correlated directly to the sodium reabsorption, consuming 2.4 times more oxygen for a certain amount of reabsorbed sodium in AKI compared to control. Restoration of MAP from 60–75 mmHg with norepinephrine, improved renal oxygen delivery, GFR and renal oxygenation in AKI patients. Increasing MAP to 90 mmHg had no further beneficial effect. Conclusions: While mannitol improves GFR at the cost of an impaired renal oxygenation, dopamine, in contrast, improves renal oxygenation, but has no effect on GFR. Furthermore, renal oxygenation is severely impaired in AKI, due to renal vasoconstriction and sodium reabsorption at a high oxygen cost. Finally, norepinephrine improves GFR and renal oxygenation when used for treatment of hypotension

Renal function and oxygenation are impaired early after liver transplantation despite hyperdynamic systemic circulation

Abstract Background Acute kidney injury (AKI) occurs frequently after liver transplantation and is associated with the development of chronic kidney disease and increased mortality. There is a lack of data on renal blood flow (RBF), oxygen consumption, glomerular filtration rate (GFR) and renal oxygenation, i.e. the renal oxygen supply/demand relationship, early after liver transplantation. Increased insight into the renal pathophysiology after liver transplantation is needed to improve the prevention and treatment of postoperative AKI. We have therefore studied renal hemodynamics, function and oxygenation early after liver transplantation in humans. Methods Systemic hemodynamic and renal variables were measured during two 30-min periods in liver transplant recipients (n = 12) and post-cardiac surgery patients (controls, n = 73). RBF and GFR were measured by the renal vein retrograde thermodilution technique and by renal extraction of Cr-EDTA (= filtration fraction), respectively. Renal oxygenation was estimated from the renal oxygen extraction. Results In the liver transplant group, GFR decreased by 40% (p < 0.05), compared to the preoperative value. Cardiac index and systemic vascular resistance index were 65% higher (p < 0.001) and 36% lower (p < 0.001), respectively, in the liver transplant recipients compared to the control group. GFR was 27% (p < 0.05) and filtration fraction 40% (p < 0.01) lower in the liver transplant group. Renal vascular resistance was 15% lower (p < 0.05) and RBF was 18% higher (p < 0.05) in liver transplant recipients, but the ratio between RBF and cardiac index was 27% lower (p < 0.001) among the liver-transplanted patients compared to the control group. Renal oxygen consumption and extraction were both higher in the liver transplants, 44% (p < 0.01) and 24% (p < 0.05) respectively. Conclusions Despite the hyperdynamic systemic circulation and renal vasodilation, there is a severe decline in renal function directly after liver transplantation. This decline is accompanied by an impaired renal oxygenation, as the pronounced elevation of renal oxygen consumption is not met by a proportional increase in renal oxygen delivery. This information may provide new insights into renal pathophysiology as a basis for future strategies to prevent/treat AKI after liver transplantation. Trial registration ClinicalTrials.gov, NCT02455115 . Registered on 23 April 2015

Prehospital monitoring of cerebral circulation during out of hospital cardiac arrest ? : A feasibility study

Background About two-thirds of the in-hospital deaths after out-of-hospital cardiac arrests (OHCA) are a consequence of anoxic brain injuries, which are due to hypoperfusion of the brain during the cardiac arrests. Being able to monitor cerebral perfusion during cardiopulmonary resuscitation (CPR) is desirable to evaluate the effectiveness of the CPR and to guide further decision making and prognostication. Methods Two different devices were used to measure regional cerebral oxygen saturation (rSO2): INVOS™ 5100 (Medtronic, Minneapolis, MN, USA) and Root® O3 (Masimo Corporation, Irvine, CA, USA). At the scene of the OHCA, advanced life support (ALS) was immediately initiated by the Emergency Medical Services (EMS) personnel. Sensors for measuring rSO2 were applied at the scene or during transportation to the hospital. rSO2 values were documented manually together with ETCO2 (end tidal carbon dioxide) on a worksheet specially designed for this study. The study worksheet also included a questionnaire for the EMS personnel with one statement on usability regarding potential interference with ALS. Results Twenty-seven patients were included in the statistical analyses. In the INVOS™5100 group (n = 13), the mean rSO2 was 54% (95% CI 40.3–67.7) for patients achieving a return of spontaneous circulation (ROSC) and 28% (95% CI 12.3–43.7) for patients not achieving ROSC (p = 0.04). In the Root® O3 group (n = 14), the mean rSO2 was 50% (95% CI 46.5–53.5) and 41% (95% CI 36.3–45.7) (p = 0.02) for ROSC and no ROSC, respectively. ETCO2 values were not statistically different between the groups. The EMS personnel graded the statement of interference with ALS to a median of 2 (IQR 1–6) on a 10-point Numerical Rating Scale. Conclusion Our results suggest that both INVOS™5100 and ROOT® O3 can distinguish between ROSC and no ROSC in OHCA, and both could be used in the pre-hospital setting and during transport with minimal interference with ALS.

Perilipin 5 is protective in the ischemic heart

Background: Myocardial ischemia is associated with alterations in cardiac metabolism, resulting in decreased fatty acid oxidation and increased lipid accumulation. Here we investigate how myocardial lipid content and dynamics affect the function of the ischemic heart, and focus on the role of the lipid droplet protein perilipin 5 (Plin5) in the pathophysiology of myocardial ischemia. Methods and results: We generated Plin5(-/-) mice and found that Plin5 deficiency dramatically reduced the triglyceride content in the heart. Under normal conditions, Plin5(-/-) mice maintained a close to normal heart function by decreasing fatty acid uptake and increasing glucose uptake, thus preserving the energy balance. However, during stress or myocardial ischemia, Plin5 deficiency resulted in myocardial reduced substrate availability, severely reduced heart function and increased mortality. Importantly, analysis of a human cohort with suspected coronary artery disease showed that a common noncoding polymorphism, rs884164, decreases the cardiac expression of PLIN5 and is associated with reduced heart function following myocardial ischemia, indicating a role for Plin5 in cardiac dysfunction. Conclusion: Our findings indicate that Plin5 deficiency alters cardiac lipid metabolism and associates with reduced survival following myocardial ischemia, suggesting that Plin5 plays a beneficial role in the heart following ischemia. (C) 2016 The Authors. Published by Elsevier Ireland Ltd