EVALUATION OF NEW CATHETER SYSTEMS FOR INTRAUTERINE PRESSURE MEASUREMENT

To verify the reliability of intrauterine pressure recordings by a new ly available intrauterine catheter. In five women in labor the tips of the two newly available catheters (Hewlett Packard HP 13975 A) were t ied together and placed in the same amniotic fluid pocket. In three ot her women the tip of the new catheter (HP) and tip of an established c atheter system (Intran II) were tied and placed in the uterine cavity above the fetal head. The difference in active pressure recorded by th e two catheters for each contraction in all 8 women was calculated. Th e total active pressure recorded for each patient for the whole labor by the two catheter was calculated. The active pressure difference for individual contractions was less than 5 mm Hg in 95% of contractions (n = 222) with the two new catheters (HP versus HP) and 99% when the n ew catheter was compared with the established catheter system (HP vers us Intran II) (n = 222). The total active pressure in each labor diffe red by 0.4% to 5.4% (n = 5) and 1.4% to 4.1% (n = 3) respectively when similar (new HP versus new KP) and different catheter systems (new HP versus established Intran II) were used. The new transducer tip cathe ter gives reliable pressure readings in-vivo. (n = 3) respectively whe n similar (new HP versus new HP) and different catheter systems (new H P versus established Intran II) were used. The new transducer tip cath eter gives reliable pressure readings in-vivo.