Marc Ziegenfuss

Extracorporeal life support devices and strategies for management of acute cardiorespiratory failure in adult patients: a comprehensive review

Evolution of extracorporeal life support (ECLS) technology has added a new dimension to the intensive care management of acute cardiac and/or respiratory failure in adult patients who fail conventional treatment. ECLS also complements cardiac surgical and cardiology procedures, implantation of long-term mechanical cardiac assist devices, heart and lung transplantation and cardiopulmonary resuscitation. Available ECLS therapies provide a range of options to the multidisciplinary teams who are involved in the time-critical care of these complex patients. While venovenous extracorporeal membrane oxygenation (ECMO) can provide complete respiratory support, extracorporeal carbon dioxide removal facilitates protective lung ventilation and provides only partial respiratory support. Mechanical circulatory support with venoarterial (VA) ECMO employed in a traditional central/peripheral fashion or in a temporary ventricular assist device configuration may stabilise patients with decompensated cardiac failure who have evidence of end-organ dysfunction, allowing time for recovery, decision-making, and bridging to implantation of a long-term mechanical circulatory support device and occasionally heart transplantation. In highly selected patients with combined severe cardiac and respiratory failure, advanced ECLS can be provided with central VA ECMO, peripheral VA ECMO with timely transition to venovenous ECMO or VA-venous ECMO upon myocardial recovery to avoid upper body hypoxia or by addition of an oxygenator to the temporary ventricular assist device circuit. This article summarises the available ECLS options and provides insights into the principles and practice of these techniques. One should emphasise that, as is common with many emerging therapies, their optimal use is currently not backed by quality evidence. This deficiency needs to be addressed to ensure that the full potential of ECLS can be achieved.

Protocol Guided Bleeding Management Improves Cardiac Surgery Patient Outcomes

Excessive bleeding is a risk associated with cardiac surgery. Treatment invariably requires transfusion of blood products; however, the transfusion itself may contribute to postoperative sequelae. Our objective was to analyse a quality initiative designed to provide an evidenced‐based approach to bleeding management.

The Influence of Circulating Levels of Fibrinogen and Perioperative Coagulation Parameters on Predicting Postoperative Blood Loss in Cardiac Surgery: A Prospective Observational Study

Fibrinogen, the major clotting protein in blood plasma, plays key roles in blood coagulation and thrombosis. In this prospective cohort study, we measured patients fibrinogen levels and common coagulation parameters before and after cardiopulmonary bypass (CPB) and examined their relationships with postoperative blood loss.

A preliminary investigation into adrenal responsiveness and outcomes in patients with cardiogenic shock after acute myocardial infarction

PURPOSE This study investigated the significance of baseline cortisol levels and adrenal response to corticotropin in shocked patients after acute myocardial infarction (AMI). METHODS A short corticotropin stimulation test was performed in 35 patients with cardiogenic shock after AMI by intravenously injecting of 250 μg of tetracosactrin (Synacthen). Blood samples were obtained at baseline (T0) before and at 30 (T30) and 60 (T60) minutes after the test to determine plasma total cortisol (TC) and free cortisol concentrations. The main outcome measure was in-hospital mortality and its association with T0 TC and maximum response to corticotropin (maximum difference [Δ max] in cortisol levels between T0 and the highest value between T30 and T60). RESULTS The in-hospital mortality was 37%, and the median time to death was 4 days (interquartile range, 3-9 days). There was some evidence of an increased mortality in patients with T0 TC concentrations greater than 34 μg/dL (P=.07). Maximum difference by itself was not an independent predictor of death. Patients with a T0 TC 34 μg/dL or less and Δ max greater than 9 μg/dL appeared to have the most favorable survival (91%) when compared with the other 2 groups: T0 34 μg/dL or less and Δ max 9 μg/dL or less or T0 34 μg/dL or higher and Δ max greater than 9 μg/dL (75%; P=.8) and T0 greater than 34 μg/dL and Δ max 9 μg/dL or less (60%; P=.02). Corticosteroid therapy was associated with an increased mortality (P=.03). There was a strong correlation between plasma TC and free cortisol (r=0.85). CONCLUSIONS A high baseline plasma TC was associated with a trend toward increased mortality in patients with cardiogenic shock post-AMI. Patients with lower baseline TC, but with an inducible adrenal response, appeared to have a survival benefit. A prognostic system based on basal TC and Δ max similar to that described in septic shock appears feasible in this cohort. Corticosteroid therapy was associated with adverse outcomes. These findings require further validation in larger studies.

Long-Term Survival and Health-Related Quality of Life in Adults After Extra Corporeal Membrane Oxygenation

BACKGROUND The study aims to determine long-term survival, health-related quality of life (HRQoL) and functional and physical outcomes of adult extra corporeal membrane oxygenation (ECMO) patients as there are limited and conflicting data in this area. METHODS All patients receiving ECMO from April 2009 until June 2014 at The Prince Charles Hospital, Brisbane had Kaplan Meier survival calculated. Quality of life (QoL) was assessed using the Short Form Health Survey (SF-36v2), EQ5D-5L, The Frenchay Activities Index (FAI) and a return to work survey. From December 2011, these measures and 6-minute walk distance (6MWD) were assessed at hospital discharge and 12 months post-discharge. RESULTS Seventy-seven (77) patients (45 veno-arterial and 32 veno-venous) received ECMO of whom 47/77 (61%) survived to hospital discharge. There were no deaths recorded in those discharged alive from the intensive care unit at median follow-up time 1,011days (range 227-2,014 days). Mean SF-36 scores (n=33) and EQ5D were assessed at a median of 606days after hospital discharge. SF-36 scores were significantly (p<0.05) worse than age-matched norms in all domains except vitality, bodily pain and mental health. Thirteen (13) (39%) participants had persistent problems with mobility and usual activity as measured by EQ5D. At 12 months post-ECMO, 6MWD was 531(IQR:397.3-626.8)m; 72% (IQR:53.2-77.6%) predicted but had improved by 223m (p=0.002) when compared to baseline. Nineteen (19) of 20 participants who had been employed pre-ECMO had returned to work. CONCLUSIONS All ECMO patients discharged from hospital were alive at follow-up. Despite improvements in physical measures and HRQoL, long-term functional deficits persist when compared to that of aged- and sex-matched norms.

The S.T.A.B. trial-standardized testing of artificial blood: a comparative study of various products that may be used as artificial blood for high fidelity simulation training in the critical care setting.

Aim: In the current climate of medical education, there is an ever-increasing demand for and emphasis on simulation as both a teaching and training tool. The objective of our study was to compare the realism and practicality of a number of artificial blood products that could be used for high-fidelity simulation. Method: A literature and internet search was performed and 15 artificial blood products were identified from a variety of sources. One product was excluded due to its potential toxicity risks. Five observers, blinded to the products, performed two assessments on each product using an evaluation tool with 14 predefined criteria including color, consistency, clotting, and staining potential to manikin skin and clothing. Each criterion was rated using a five-point Likert scale. The products were left for 24 hours, both refrigerated and at room temperature, and then reassessed. Statistical analysis was performed to identify the most suitable products, and both inter- and intra-rater variability were examined. Results: Three products scored consistently well with all five assessors, with one product in particular scoring well in almost every criterion. This highest-rated product had a mean rating of 3.6 of 5.0 (95% posterior Interval 3.4–3.7). Inter-rater variability was minor with average ratings varying from 3.0 to 3.4 between the highest and lowest scorer. Intrarater variability was negligible with good agreement between first and second rating as per weighted kappa scores (K = 0.67). Conclusion: The most realistic and practical form of artificial blood identified was a commercial product called KD151 Flowing Blood Syrup. It was found to be not only realistic in appearance but practical in terms of storage and stain removal.