Survey of Blood Transfusion Practices in Critically Ill Patients at High Altitude

Anemia has been identified as a common complication in the critically ill patient. Approximately 40 and 60% are transfused in normal clinical practice. However transfusions are not free of adverse events including: transfusion-associated lung injury, infectious complications, progression of organ failure, fluid overload associated with transfusion, among others. Therefore, several clinical trials have been designed to define red blood cell transfusion thresholds. Mainly two groups have been compared: 1) liberal schemes in which patients are transfused with higher levels of hemoglobin (generally ≤ 10 g / dL) and restrictive regimens with lower levels (≤ 7 g / dL). Institutions such as the British Committee for Standards in Hematology have developed recommendations in favor of restrictive strategies based mainly on the TRICC (Transfusion Requirements In Critical Care) study conducted by Hebert et al.

On the other hand, it is well known that as consequences of living in places at high altitude physiological modifications occur in the human. One of these adaptations is the increase in hemoglobin levels occurring in people living at high altitude, especially in Andean residents, in whom the hypoxia promotes an increase in the production of red blood cells.

The recommendation of the restrictive strategy in the transfusion of red blood cells has been adopted in several countries with numerous populations living at high altitudes, although this practice has not been evaluated in these patients.

The purpose of this study is to describe the current practice on transfusion of red blood cells in critical patients treated in intensive care units located in high altitude areas (over 1500 m) to determine whether physicians follow the recommendations of restrictive strategies.

This is an observational, non-randomized, cross-sectional survey performed with intensivists of Bolivia, Colombia, Ecuador, México and Perú. The data will be collected from an on-line scenaries based survey. The survey is designated to assessed the effect of severity, need of surgery, severe hypoxia, and alteration in tisular perfusion as modifiers of transfusion thresholds. Besides unit characteristics as geographical altitude and type of unit will be collected.