Acute lower limb arterial ischaemia: a role for continuous oxygen inhalation

Simultaneous readings of transcutaneous partial pressure of oxygen (Ptc,O2) were obtained from the left anterior chest wall, from 10 cm distal to the medial aspect of the knee joint, and from the first dorsal webspace in 16 patients with acute peripheral arterial ischaemia of the leg. Oxygen was administered at concentrations of 24, 40, 60 and 100 per cent. Mean (s.d.) initial chest Ptc,O2 (53(17)mmHg) was significantly higher than that of the medial lower limb site (37(17)mmHg). After inhalation of 24 per cent oxygen, a statistically significant (P less than 0.025) increase in chest Ptc,O2 was achieved (63(20)mmHg), but the increase in Ptc,O2 (43(19)mmHg) at the medial lower limb site was not statistically significant. Inhalation of 40 per cent oxygen resulted in significant increases at both sites (chest: 83(23)mmHg, P less than 0.01; limb: 53(26)mmHg, P less than 0.05). Ptc,O2 in the limb at this concentration of inhaled oxygen was equal to the initial chest level. Increasing the oxygen concentration to 60 per cent and then to 100 per cent produced further significant (P less than 0.001) increases in Ptc,O2 at both sites. The use of continuous oxygen inhalation during acute ischaemia may improve tissue nutrition before, during and after definitive treatment.