Effects of positive end-expiratory pressure on splanchnic circulation and function in experimental peritonitis
D. Arvidsson, P. Almquist and U. Haglund
Department of Surgery, University Hospital, Uppsala, Sweden.
Splanchnic and central hemodynamic effects of positive end-expiratory
pressure (PEEP) were studied in anesthetized pigs using mechanical
ventilatory assistance, with or without sepsis (fecal peritonitis). One
hour after sepsis, PEEP (10 cm H2O) was applied (n = 6). Another group (n =
6) had sepsis without PEEP. In one group (n = 6) without sepsis, PEEP was
applied after 1 hour, while a fourth group (n = 5), without sepsis or PEEP,
served as a control. The group with PEEP and sepsis had reduced cardiac
index, portal venous blood flow, and liver surface blood flow. The group
with PEEP alone had reduced splanchnic circulation by increasing
gastrointestinal vascular resistance, while the group with sepsis alone had
increased portal vascular resistance. In a separate series with sepsis,
intermittent PEEP, and vigorous fluid resuscitation, it was demonstrated
that avoiding hypovolemia did not seem to protect from the PEEP effects on
the splanchnic circulation. The combination of sepsis and PEEP was not
additive on portal blood flow reduction but reduced bile production.
