Treatment of pulmonary air embolism with hyperbaric oxygen and isoproterenol in rats



Treatment of pulmonary air embolism with hyperbaric oxygen and isoproterenol in rats

Objective

To study the effectiveness of hyperbaric oxygen therapy with a combination of isoproterenol for treatment of pulmonary embolism. Pulmonary air embolism is the lodging of air bubbles in the pulmonary circulation. This condition consequently, causes pulmonary edema, impairment in cardiopulmonary functions and pulmonary hypertension (Huang, Kang, Wan, 2002). These complications are lethal if not treated on time as it causes a hindrance in the blood flow and ultimately compromised blood supply to the brain can cause brain death as well. Hence this study focused on determining the effects of hyperbaric oxygen therapy on acute lung injury which was induced in vivo through venous air infusion in experimental rats.

Type of Research

The method of research used in this model was experimental. The femoral artery of the experimental rat was used to monitor the pulmonary and systemic arterial pressures by introducing intra arterial catheters. The pulmonary air embolism was artificially induced in rats by infusing air at the rate of 25 microL x min(-1). Measurements of protein concentration, LDH activity in the (BAL) broncheoalveolar lavage and wet/dry weight of lung ratio were taken ultimately in the experiment (Staffan, 1970). Experimental studies on rats provided an induced or controlled medium to evaluate the efficacy of newly introduced hyperbaric oxygen therapy in which a pressure of oxygen which is more than that of the atmospheric pressure of oxygen is used in a closed cell to induce an artificial pressure cell which can effectively deliver the oxygen and reduce the oxidative stress following acute injuries, in this case the acute lung injury caused by venous air embolism.

Findings

The mean pulmonary pressure was increased by infusion of air to a plateau just within 10 minutes which was actually 208% more than the baseline values. The wet/dry ratio of lungs measured through this technique was found to be 4.83 +/- 0.28, 4.98 +/- 0.39, and 5.20 +/- 0.38 in the groups receiving 0.13, 0.50, and 1.0 ml of infused air in the pulmonary venous circulation respectively. This measurement was significantly more than the measurements of the control group which averaged to 4.47 +/- 0.24. The concentration of protein measured in (mg x L(-1)) and the activity of LDH which was measured in (mAbs x min(-1)) present in broncheoalveolar lavage fluid was increased from the level of ...