Skin surface oxygen pressure fields during administration of prostaglandin E1 in patients with arterial occlusive disease

Effects of Alprostadil (synthetic prostaglandin E1) on red and white cell filterability during cardiopulmonary bypass

Reduced blood cell rheology due to mechanical blood trauma is associated with reduced microcirculation and organ dysfunction during and following cardiac surgery using cardiopulmonary bypass (CPB). The influence of prostaglandin E1 (PGE1) on the blood cell rheology was studied in 24 patients undergoing coronary artery bypass grafting surgery with the use of CPB. Intra-operative infusion of PGE1 was given to 12 patients in a dose of 20ng/kg/min; the other 12 patients served as controls. Red and white cell rheology were measured by red and white cell filtration rate (RFR and WFR) respectively, applying a standard bulk filtration technique. Blood samples were collected pre-operatively, at the start of CPB, after 30 minutes, 60 minutes, 90 minutes and at the end of CPB. Results showed that the mechanical trauma of CPB was better tolerated in the PGE1 group, where RFR and WFR showed significant lower losses during CPB (p < 0.001, p < 0.001). These results indicate that PGE1 has beneficial effects on red and white cell deformability during CPB. The improvement of blood rheology would be expected to lead to better microcirculation in the vital organs.

Skin oxygen pressure histograms in patients with peripheral arterial occlusive disease during intraarterial and intravenous prostaglandin E1 infusions of different dosages and their prognostic value

Skin surface oxygen pressure fields (tcPO2 [37 degrees C]) reproducibly characterize skin microcirculation in patients with peripheral arterial occlusive disease. These appear suited for investigation of short- and long-term effects of vasoactive drug treatment. The authors studied whether skin surface oxygen pressure histograms change depending on dosage and route of administration of prostaglandin E1 (PGE1), whether they are of predictive value for patients' clinical outcome, and whether they normalize after therapy with PGE1. The authors investigated 15 patients with various degrees of disease and measured forefoot oxygen histograms consisting of at least 80 single tcPO2 (37 degrees C) values before and during intraarterial infusion (1.5, 3, or 6 ng/kg/minute) and intravenous infusion (4.5, or 9 ng/kg/minute). The measurements were repeated two and six hours after the end of intraarterial application of 1.5 ng/kg/minute. Furthermore, the orthostatic vasoconstrictor response was tested. Skin oxygen pressure histograms were controlled after a period of twenty-two (mean) days of intraarterial PGE1 therapy. Resting histograms were left shifted with median tcPO2 (37 degrees C) between 1 and 7 mm Hg. During intraarterial application, histograms were shifted to lower tcPO2 (37 degrees C) values in most patients. Only in 3 diabetic subjects with proximal or acral obliterations was a marked increase observed. The alterations were detectable at least two hours after the end of the infusion. During intravenous infusion, histograms did not change in most cases. After long-term therapy, histograms were substantially unchanged. A pathologic vasoconstrictor response, which was present in 10 patients, could not be restored. Despite a marked deterioration of the histograms the clinical outcome was favorable in 7 patients. Patients with a high resting tcPO2 (37 degrees C) (median 4 mm Hg and more) and those with a vasoconstriction on orthostasis are likely to respond to PGE1 therapy.