[Central venous catheterization using ECG monitoring and its obstetrical application (author's transl)]

We tried the central venous catheterization using the ECG monitoring lead by the catheter tip without the X-ray examination. The catheter consists of 5F sized, 70 cm, thin-walled polyethylene tube. The apex of the catheter is 60 degrees curved with heating and the exchangeable metal adaptor is attached in the proximal end. The catheter was introduced percutaneously into the cubital vein and filled with saline. The ECG lead from the catheter tip was recorded through the metal adaptor by the battery electrocardiograph. The introduction into the right atrium of the catheter was easily judged in almost all cases by the intraatrial ECG, namely, deep negative or biphasic P wave. We have tried this method in 72 cases and the success rate of insertion into the right atrium was as high as 87.5%. The right atrial pressure of the obstetrical group (19 term pregnant women) was significantly lower than that of the gynecological group (22 preoperative patients) (P less than 0.01). The pH of the right atrial blood in the obstetrical group was significantly higher than that in the gynecological group (P less than 0.01). PCO2, PO2, HCO3-, and the oxygen saturation of the obstetrical group were significantly lower than those of the gynecological group (P less than 0.01).