Liver tissue partial pressure of oxygen and carbon dioxide during partial hepatectomy

Background. Data on tissue oxygen partial pressure (Pt_O2) andcarbon dioxide partial pressure (Pt_CO2) in human liver tissueare limited. We set out to measure changes in liver Pt_O2 andPt_CO2 during changes in ventilation and a 10 min period of ischaemiain patients undergoing liver resection using a multiple sensor(Paratrend^® Diametrics Medical Ltd, High Wycombe, UK). Methods. Liver tissue oxygenation was measured in anaesthetizedpatients undergoing liver resection using a sensor insertedunder the liver capsule. Pt_O2 and Pt_CO2 were recorded with FI_O2values of 0.3 and 1.0, at end-tidal carbon dioxide partial pressuresof 3.5 and 4.5 kPa and 10 min after the onset of liver ischaemia(Pringle manoeuvre). Results. Data are expressed as median (interquartile range).Increasing the FI_O2 from 0.3 to 1.0 resulted in the Pt_O2 changingfrom 4.1 (2.6–5.4) to 4.6 (3.8–5.2) kPa, but thiswas not significant. During the 10 min period of ischaemia Pt_CO2increased significantly (P<0.05) from 6.7 (5.8–7.0)to 11.5 (9.7–15.3) kPa and Pt_O2 decreased, but not significantly,from 4.3 (3.5–12.0) to 3.3 (0.9–4.1) kPa. Conclusion. Pt_O2 and Pt_CO2 were measured directly using a Paratrend^®sensor in human liver tissue. During anaesthesia, changes inventilation and liver blood flow caused predictable changesin Pt_CO2. Br J Anaesth 2004; 92: 735–7