Experimental evaluation of various available contrast agents for use in the upper gastrointestinal tract in case of suspected leakage. Effects on lungs.

The reactions of seven contrast agents--pure barium sulphate, Micropaque, Gastrografin, Dionosil, Hytrast, Amipaque and Hexabrix--on the bronchi and lungs of rats were studied. This work was undertaken to find a safe gastrointestinal contrast agent for use in post-operative patients where aspiration may be an accompanying risk. Amipaque and Hexabrix produced no significant histological reaction in the lungs and would, therefore, appear to be suitable for use in such cases.