OBJECTIVETo observe the local tissue oxygenation in acupoint Zusanli (ST36) of patients in critical condition, and to assess the value of applying tissue oxygen measurement via acupoint in clinical practice.

METHODSThirty-six patients with severe illness undergoing invasive positive pressure ventilation (IPPV) were divided into the infected group (n=13) and the non-infected group (n=23). Tissue oxygen pressure (PtO2) in the right acupoint Zusanli was measured with tissue oxygen tension detector when the concentration of inspired oxygen (FiO2) was 40% and 100% respectively, meanwhile, the arterial blood oxygen pressure (PaO2) was also determined to calculate PtO2 index (the ratio of PtO2/PaO2).

RESULTSThere was a positive correlation between PtO2 and PaO2 (P < 0.05); PaO2 in the infected group was lower, and PtO2 index and PtO2 were higher significantly, as compared with those in the non-infected group (all P < 0.05). As FiO2 adjusted from 40% to 100%, the increment of PtO2 in the infected group was significantly higher than that in the non-infected group (P < 0.05).

CONCLUSIONFor the severely infected patients with obstacle of systemic oxygen delivery, the local tissue oxygen demand of acupoints increases significantly, and the tissue oxygen delivery dependence is enhanced, in this time, the tissue might fulfill the oxygen demand itself through elevating PtO2 index. It is of great significance to monitor tissue oxygen pressure in acupoint to determine the state of local tissue oxygenation in critically illed patients.