Clinical use of venoarterial extracorporeal membrane oxygenation.

With advances in mechanical circulation, venoarterial extracorporeal membrane oxygenation has become an established technique to provide cardiopulmonary support for patients with cardiovascular collapse. This article reviews the physiological principles of such extracorporeal technique and its interaction with the native heart. Practical aspects including equipment, patient selection, and common complications with their prevention and specific management are summarised. The strategy for weaning from venoarterial extracorporeal membrane oxygenation is also discussed.

Clinical use of venovenous extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation has been used clinically for more than 40 years. The technique provides respiratory and/or circulatory support via venovenous and veno-arterial configurations, respectively. We review the basic physiological principles of extracorporeal membrane oxygenation systems in venovenous extracorporeal membrane oxygenation. Clinical aspects including patient selection, equipment, setup, and specific patient management are outlined. Pros and cons of the use of extracorporeal membrane oxygenation in respiratory failure are discussed.

Acquired factor V inhibitor in a patient receiving venous-venous extracorporeal membrane oxygenation for Legionella pneumonia.

We report a rare complication of factor V deficiency in a patient having Legionella pneumonia. This patient also had other complications like severe acute respiratory distress syndrome, acute kidney injury, and septic shock that required venous-venous extracorporeal membrane oxygenation support. This is the first reported case of acquired factor V deficiency in a patient receiving extracorporeal membrane oxygenation for Legionella pneumonia. With the combined use of intravenous immunoglobulin, rituximab and plasma exchange, we achieved rapid clearance of the factor V inhibitor within 1 week so as to allow safe decannulation of extracorporeal membrane oxygenation.

Three-year experience of using venovenous extracorporeal membrane oxygenation for patients with severe respiratory failure.

OBJECTIVE: To present the 3-year experience of using venovenous extracorporeal membrane oxygenation for patients with severe respiratory failure in a single centre in Hong Kong. DESIGN: Case series. SETTING: A 19-bed Intensive Care Unit of a tertiary hospital in Hong Kong. PATIENTS: All patients who were managed with venovenous extracorporeal membrane oxygenation from 1 July 2010 to 30 June 2013 in the Intensive Care Unit. RESULTS: Overall, 31 patients (mean age, 42.2 years, standard deviation, 14.1 years; 21 males) received venovenous extracorporeal membrane oxygenation for the treatment of severe respiratory failure. Of these, 90.3% (28 patients) presented with pneumonia as the cause of the respiratory failure, and 22 of them had identifiable causes. A total of nine (29.0%) patients were diagnosed to have H1N1 infection. The median Murray score was 3.5 (interquartile range, 3.0-3.5); the median duration of venovenous extracorporeal membrane oxygenation support was 5.0 (2.8-8.6) days; and the median duration of mechanical ventilator support was 18.2 (7.8-27.9) days. The overall intensive care unit mortality was 19.4% (n=6). The overall in-hospital mortality and the 28-day mortality were both 22.6% (n=7). Among the 22 patients who had identifiable infective causes, those suffering from viral infection had lower intensive care unit and hospital mortality than those who had bacterial infection (8.3% vs 20.0%). All the H1N1 patients survived. Complications related to extracorporeal membrane oxygenation included severe bleeding (n=2; 6.5%) and mechanical complications of the circuits (n=3; 9.7%). CONCLUSIONS: Venovenous extracorporeal membrane oxygenation is an effective adjunctive therapy and can be used as a life-saving procedure for carefully selected patients with severe acute respiratory distress syndrome when the limits of standard therapy have been reached.

Uncommon cause of severe pneumonia: co-infection of influenza B and Streptococcus.

Influenza and pneumococcus co-infection can cause severe morbidity and mortality. Usually, this entails influenza A, while infection by influenza B is rarely serious. The literature describes influenza A epidemics leading to prolific loss of lives, notably the 1918 epidemic was blamed for the deaths of 40 to 50 million people. In this report, four patients were infected by influenza B during the influenza epidemic of 2011/12 in Hong Kong. All of them were previously healthy and had no chronic diseases; they were admitted to the hospital due to influenza-like symptoms. They rapidly deteriorated with multi-organ failure, and were subsequently diagnosed to be infected with influenza B and streptococci that gave rise to severe pneumonia. Three of them were infected with Streptococcus pneumoniae and one with Streptococcus pyogenes. All of them had leukopenia, septic shock, and acute kidney injury; two of whom died despite aggressive antibiotic treatment and organ support in the intensive care unit. According to the literature, this is the second case report of severe invasive pneumococcal pneumonia secondary to influenza B infection.