ENDOTRACHEAL SUCTIONING - AN EXAMPLE OF THE PROBLEMS OF RELEVANCE ANDRIGOUR IN CLINICAL RESEARCH

Endotracheal suctioning is a routine but potentially dangerous procedu re. The literature documenting approaches to minimizing the cardiopulm onary complications of endotracheal suctioning is reviewed. Hyperoxyge nation, hyperventilation, hyperinflation and the use of adaptors are a ll evaluated. The effects of endotracheal suctioning on haemodynamics and oxygen transport are also examined. The traditional dualist approa ch to the respiratory and cardiovascular systems is contrasted with th e recent emphasis on oxygen transport by the cardiopulmonary system. T he trade-off between the rigour of laboratory studies (which can be we ll controlled but are difficult to generalize) and the relevance of cl inical research (which is more easily generalized but which often lack s internal validity) is discussed. Although research studies have beco me both more methodologically and conceptually sophisticated, definiti ve recommendations for a safe and effective suctioning procedure still remain elusive.