Effects of Normal Saline Instillation
on Oxygenation
Kinloch15 conducted a descriptive observational study
to describe the effects of instillation of normal saline
into an endotracheal tube before suctioning on mixed
venous oxygen saturation in critically ill patients. The
researcher examined 35 patients recovering from coronary
artery bypass graft surgery in a cardiovascular
ICU. He found that saline instillation into an endotracheal
tube significantly reduced the mixed venous oxygen
saturation. This study found that the mixed venous
oxygen saturation was decreased in patients who had
instillation of normal saline, and it took an average of
3.78 minutes for mixed venous oxygen saturation to
return to the baseline when compared with the nonnormal
saline instillation group. Similar findings were
recorded in other studies.16