Gastrointestinal problems in children
on home invasive mechanical ventilation
The gastrointestinal (GI) problems in critically ill patients who were
given MV support in intensive care units have been demonstrated both in
animal and human studies24-26. During MV, splanchic
hypoperfusion seems to play an important role in the pathogenesis of GI
complications due to cardiocirculatory dysfunction. In particular, it
was reported that high positive end-expiratory pressure (PEEP) levels
(PEEP >15 cmH2O) cause an increased right
ventricular afterload which lead to an increase in right atrial
pressure, decreased systemic venous return and cardiac output and
splanchic perfusion respectively24-27. Also acute
moderate increase in arterial carbondioxide level has been observed to
increase hepatic and splanchic blood flow in a biphasic manner;
initially reducing of blood flow due to sympathetic stimulation, then
increasing blood flow due to direct vasodilator effect of
carbondioxide28. Despite there are conflicting results
on the effect of PEEP on hepatic blood flow as decreased or no change.
The decrease in portal flow may be compansated with increased arterial
blood flow in order to maintain hepatic blood
flow29,30. The gastro-esophageal reflux disease,
dysphagia, delayed gastric emptying and constipation are the most common
gastrointestinal problems of the children with tracheostomy on
MV31-33.