SKELETAL-MUSCLE PARTIAL-PRESSURE OF OXYGEN IN PATIENTS WITH SEPSIS

Objective: In order to obtain direct evidence for tissue hypoxia in pa tients with sepsis oxygen, partial pressure was measured within skelet al muscle. Furthermore, serial intermittent and continuous measurement s of skeletal muscle Po-2 in patients with sepsis were used to find ou t whether skeletal muscle oxygenation may change in the course of seps is and depends on the severity of sepsis. Design: Prospective study. S etting: Intensive care unit of a university hospital. Patients: Intens ive care patients (n = 98) with sepsis (group 1, n = 39; group 4, n = 28), limited infection (group 2, n = 16), and cardiogenic shock (group 3, n = 15). Interventions: Pulmonary artery catheterization; standard antibiotic therapy and volume replacement. Measurements and Main Resu lts: Skeletal muscle Po-2 was determined by polarographic needle elect rodes or cathether probes. In patients with sepsis (n = 67), no eviden ce for skeletal muscle hypoxia was obtained from the Po-2 distribution within biceps muscle. Mean skeletal muscle Po-2 was increased in pati ents with sepsis (group 1, 48 torr [6.4 kPa]) compared with patients w ith limited infection (group 2, 28 torr [3.7 kPa]), p < .001) and with patients with cardiogenic shock (group 3, 22 torr [2.9 kPa], p < .001 ). Serial measurements of the Po-2 distribution during seven consecuti ve days in another 28 patients (group 4) with sepsis showed that a mor e severe degree of sepsis was associated with an increase of mean skel etal muscle (p < .001). These results were confirmed by continuous mea surements of mean skeletal muscle Po-2. using Po-2 catheters. Conclusi ons: In patients with sepsis, oxygen transport to skeletal muscle was not critically reduced. Serial intermittent and continuous measurement s of skeletal muscle Po-2 showed that skeletal muscle Po-2 increased i n relation to the severity of the stage of sepsis. Our findings sugges t that oxygen utilization within skeletal muscle decreased with deteri oration of sepsis, thereby increasing skeletal muscle Po-2.