[Epidemiology of acute pulmonary injury and acute respiratory distress syndrome]

Unilateral pulmonary edema associated factors after minimally invasive mitral valve surgery

BACKGROUND AND OBJECTIVES

In recent years, minimally invasive cardiac surgery (MICS) has been developed and applied to a greater number of pathologies, especially in mitral valve surgeries, as it obtains results comparable to those of conventional techniques while entailing lower surgical trauma and shorter recovery time. MICS requiring one-lung ventilation has been associated to the appearance of unilateral pulmonary edema (UPE), which is a potentially serious complication. The objective is determining the incidence of UPE after mitral MICS and its development associated factors.

MATERIAL AND METHODS

Observational descriptive and single-center study analyzing data from patients undergoing mitral valve MICS (right mini-thoracotomy) consecutively collected between the years 2015 and 2017.

RESULTS

A total of 93 patients were included and 26 presented UPE. The most common complications after mitral valve MICS were atrial fibrillation (38.7%), UPE (28%) and transient and/or definitive second- or third-degree auriculoventricular block (19.4%). The UPE group had longer ICU stay (3.3 ± 8.0 vs. 1.84 ± 2.23 days) and longer total hospitalization length-of-stay (15.5 ± 34.7 vs. 10.6 ± 7.5 days). The mortality in the UPE group was 3.9%. A significant association was found between the following collected variables and the development of postoperative UPE: preoperative baseline pulse oximetry, preoperative use of ACE inhibitors, postoperative atrial fibrillation and 24 first-hours cumulative chest tube drainage volume on the first 24 h.

CONCLUSIONS

The incidence of UPE is high and its appearance is associated with a longer ICU and total length of stay. More studies are required to understand its pathophysiology and apply measures to help decreasing its appearance.

[Lung diffusion capacity and quality of life 6 months after discharge from the ICU among survivors of acute respiratory distress syndrome due to influenza A H1N1]

OBJECTIVE

An evaluation is made of lung function and quality of life 6 months after discharge from the Intensive Care Unit (ICU) among survivors of acute respiratory distress syndrome (ARDS) due to pandemic 2009 influenza A H1N1, based on studies of lung function and the EQ-5D health questionnaire.

DESIGN

Case series.

SETTING

The ICU of Dr. Leónidas Lucero Acute Cases Municipal Hospital, Bahía Blanca, Argentina.

PATIENTS

PATIENTS discharged from the ICU who had been admitted with ARDS in 2009 due to influenza A H1N1.

RESULTS

Eleven patients were studied. Seven were positive for influenza H1N1 and four were negative. The mean age was 37±9.5 years, and 73% were males. Quality of life, as measured by the EQ-5D, showed changes in the 5 components in all patients, particularly in the pain/discomfort dimension 1.55±0.52; health status (EQ%health) was 70%±24. The indices adjusted for Argentina were Time Trade Off (TTO) 0.903±0.085 and Visual Analog Scale (VAS) 0.827±0.153. In all patients, spirometry and the study of pulmonary diffusion (DLCO) showed values of >80%. There was no correlation between lung diffusion and quality of life (%DLCO and EQ%health). A correlation was observed between quality of life and TTO (EQ%health and TTO), and between quality of life and the VAS score (EQ%health and VAS).

CONCLUSION

Although the sample is small, our results suggest that patients with ARDS due to influenza A H1N1 evaluated 6 months after discharge from the ICU show no deterioration of lung function, and the impact on quality of life is moderate-in contrast to the situation found in patients with ARDS of other etiologies.

Consequences of hyperoxia and the toxicity of oxygen in the lung

Oxygen (O(2)) is life essential but as a drug has a maximum positive biological benefit and accompanying toxicity effects. Oxygen is therapeutic for treatment of hypoxemia and hypoxia associated with many pathological processes. Pathophysiological processes are associated with increased levels of hyperoxia-induced reactive O(2) species (ROS) which may readily react with surrounding biological tissues, damaging lipids, proteins, and nucleic acids. Protective antioxidant defenses can become overwhelmed with ROS leading to oxidative stress. Activated alveolar capillary endothelium is characterized by increased adhesiveness causing accumulation of cell populations such as neutrophils, which are a source of ROS. Increased levels of ROS cause hyperpermeability, coagulopathy, and collagen deposition as well as other irreversible changes occurring within the alveolar space. In hyperoxia, multiple signaling pathways determine the pulmonary cellular response: apoptosis, necrosis, or repair. Understanding the effects of O(2) administration is important to prevent inadvertent alveolar damage caused by hyperoxia in patients requiring supplemental oxygenation.

[Acute lung injury and acute respiratory distress syndrome: a genomic perspective]

Genomics have allowed important advances in the knowledge of the etiology and pathogenesis of complex disease entities such as acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Genomic medicine aims to personalize and optimize diagnosis, prognosis and treatment by determining the influence of genetic polymorphisms in specific diseases. The scientific community must cope with the important challenge of securing rapid transfer of knowledge to clinical practice, in order to prevent patients from becoming exposed to unnecessary risks. In the present article we describe the main concepts of genomic medicine pertaining to ALI/ARDS, and its currently recognized clinical applications.

[Prevalence and treatment of anemia in critically ill patients]

Anemia is a common condition among medical and surgical patients admitted to the intensive care unit (ICU) and generally has a multifactorial origin. In order to avoid the deleterious effects of anemia, 40% of ICU patients receive allogenic blood transfusion (ABT). This figure increases up to 70% if the ICU stay is longer than 7 days. However, ABT is associated with a dose-dependent increase in morbidity and mortality. In contrast, the administration of exogenous erythropoietin plus iron supplements, especially iv iron, improves anemia and reduces ABT requirements, although it does not reduce mortality. To ascertain whether treatment of anemia in the critically ill with exogenous erythropoietin and iron might improve outcomes and to optimize drug administration schedules and dosage, further studies with sufficient statistical power and adequate follow-up are warranted.