抄録
The pattern of E. C. G. during bilateral open chest under various degree of positive pressure was studied in 12 rabbits.
1. RR and QT interval: In all cases, these values lay within the normal limits before operation prolonged by open chest under 4cm. and 16cm. of water constant positive pressure and in over half of all cases these values changed to outside the normal limits. Over half of the observed values of QT interval lay outside normal range of the standard error of the calculated mean. Most of them become short under 8cm. of water constant positive pressure and lay within the normal limits.
2. P wave: Pulmonary P appeared under 8cm. and 16cm. of water constant positive pressure.
3. T wave: In each lead it became remarkably flat, especially T2, under 4cm. and 16cm. of water constant positive pressure. it was slightly flat under 8cm. of water positive pressure.
