[Experimental and clinical investigations on the effects of carbon dioxide gas during hysteroscopy (author's transl)].

The acute toxicity, lethal dosage and mechanical effects of carbon dioxide gas were studied in the waking dog by intravenous and intra-arterial insufflation. The threshold dosage for toxicity was 400 ml per minute in the dog. The important factor in the toxicity was not the total volume of carbon dioxide but the volume per unit of time. Metabolic acidosis was responsible for changes in the EKG, the heart rate and the respiratory rate. These findings are discussed in relationship to the usage of carbon dioxide gas for hysteroscopy in the human female. During carbon dioxide gas hysteroscopy blood gas analyses were done in 40 patients. 28 patients had a hysteroscopy under general anaesthesia and 12 patients under local anaesthesia. It was found that the volume of carbon dioxide used for the creation of a pneumometra in hysteroscopy has no side effect. The necessary gas flow is too small for toxic side effects or mechanical side effects such as a gas embolisation.