Approach of the pulmonary valve using right heart bypass and bicaval cannula: experimental study.

Objective: To reproduce the surgery for correction of pulmonary valve anomalies using right heart bypass and a new bicaval cuffed venous cannula for minimal access surgery.

Methods: Fifteen Large-White pigs were used for this study. The standard technique model was established with the first five pigs, the experiment was done with nine animals by sternotomy, and one was submitted to a minimally invasive procedure, but has been excluded of the sample. Bicaval drainage by a single cannula was obtained through the internal jugular vein. The cuffs were inflated to increase blood flow to the machine. The return was established by putting the arterial cannula into the pulmonary artery trunk. Pre-bypass parameters were measured and compared with the parameters during the right bypass: Median Arterial Tension (MAT); Heart Rate (HR); O2 Saturation (SAT O2); end-tidal CO2 measures (etCO2); Temperature (T). The statistical analysis was done comparing the pre-bypass and during bypass values.

Results: Pre-bypass values: MAT: 90.8 mmHg; HR = 101.6 beat/min; O2 SAT = 93.8%; PetCO2 = 28.4 mmHg; T = 36.1 degrees C. During bypass the obtained values were: MAT: 88.1 mmHg; HR = 98.0 beat/min; O2 SAT = 93.1%; PetCO2 = 25.3 mmHg; T = 36.9 degrees C. Comparing the average values between the two abovementioned moments, no significant difference occurred in MAT, HR and O2 SAT; PetCO2 and T presented significant differences.

Conclusions: The bicaval cuffed venous cannula showed efficient drainage of both venae cavae with appropriate hemodynamic parameters during right bypass allowing access to the pulmonary valve.