Objective: To study the effects of pretreatment with pentoxifylline before cardiac surgery on postoperative organ function in elderly patients (>80 yrs) undergoing cardiac surgery.
Design: Prospective, randomized, placebo-controlled study.
Setting: Two-day clinical investigation in an intensive care unit of a university-affiliated hospital.
Patients: Forty elderly patients (age >80 yrs) undergoing first-time elective aortocoronary bypass grafting.
Interventions: In 20 patients, pentoxifylline (loading bolus of 300 mg followed by a continuous infusion of 1.5 mg.kg-1.hr-1 until the second postoperative day) was given after induction of anesthesia; another 20 patients received saline solution as placebo.
Measurements and main results: Concentrations of soluble adhesion molecules (soluble E-selectin, soluble vascular cell adhesion molecule-1, and soluble intercellular adhesion molecules) were measured to assess endothelial function. Liver function was evaluated by monoethylglycinexylidide test and by measuring alpha-glutathione S-transferase plasma concentrations. Renal function was assessed by measuring serum creatinine and urine concentrations of alpha-1-microglobulin. Splanchnic perfusion was assessed by monitoring intramucosal pH by using continuous tonometry. All measurements were performed before pentoxifylline infusion (T0), at the end of surgery (T1), 5 hrs after surgery (T2), and at the morning of the first (T3) and second (T4) postoperative day. Postoperative concentrations of all measured soluble adhesion molecules were significantly higher in the nontreated controls than in the pentoxifylline-treated patients. Monoethylglycinexylidide serum concentrations were significantly lower and abnormal (<50 ng/mL) postoperatively only in the untreated control patients. alpha-Glutathione S-transferase increased in both groups with a significantly higher increase in the control group (from 3.2 +/- 1.2 to 24.1 +/- 4.2 ng/mL) than in the pentoxifylline-treated patients (from 3.8 +/- 1.9 to 11.5 +/- 2.1 ng/mL). Serum creatinine was unchanged in both groups, whereas alpha-1-microglobulin increased significantly more in the control group than in the pentoxifylline-treated group. Intramucosal pH remained almost unchanged in the pentoxifylline patients (>7.35) but decreased significantly in the control group (5 hrs after surgery, intramucosal pH 7.29 +/- 0.13).
Conclusions: Pretreatment of patients aged >80 yrs undergoing cardiac surgery with pentoxifylline attenuated deterioration of endothelial, renal, and liver function as seen in an untreated control group. Splanchnic perfusion also appears to be improved in the pentoxifylline-treated group. Whether pretreatment with pentoxifylline will improve outcome in this patient population remains to be elucidated.