Cytokines and pediatric open heart surgery with cardiopulmonary bypass

It is well known that, subsequent to cardiopulmonary bypass, and particularly in children, an inflammatory response within the body can often result in a characteristic syndrome. Recently, it has been suggested that this phenomenon is due to a systemic inflammatory response, with significant involvement of cytokines. With this in mind, we investigated the behavior of tumour necrosis factor-alpha and interleukin-6 during the operative and in the immediate postoperative period in a group of children submitted to open heart surgery. We investigated any possible relation between the levels of these cytokines in the serum and the length of cardiopulmonary bypass, with the serum levels of lactate, and with the extent of use of inotropic drugs in postoperative period. The cytokines were measured in samples withdrawn after induction of anesthesia, after 10 minutes of cardiopulmonary bypass, after re-establishment of circulation, and then 2 and 24 hours after the end of cardiopulmonary bypass. The levels of tumour necrosis factor-alpha and interleukin-6 increased between the beginning and at two hours of the end of cardiopulmonary bypass. There was no correlation between the levels of these cytokines in the serum and the length of cardiopulmonary bypass, although there was a positive relation between levels of interleukin-6 and lactate in samples withdrawn at two hours of the end of bypass, and the measured levels of the cytokines correlated with the extent of inotropic drugs employed in the postoperative period.

Reconstruction of the pulmonary valve and outflow tract with bicuspid prosthesis in tetralogy of Fallot

BACKGROUND

Right ventricular outflow tract and pulmonary valve implant in patients with tetralogy of Fallot may be required to avoid late postoperative right ventricular impairment. The use of porcine bicuspid prosthesis might be a technical alternative, although comprehensive studies on the long-term use of these prostheses are not available.

METHODS

Sixty-three patients (aged 5 months to 34 years; mean, 6 years) with tetralogy of Fallot and pulmonary hypoplasia underwent surgical repair and enlargement of the right ventricular outflow using preserved porcine pulmonary bicuspid prostheses. Fifty-two patients (82.5%) were followed and underwent clinical evaluation and serial Doppler echocardiography. The first 15 patients (29.4%), with ages ranging from 5 to 16 years (mean, 8.2 years) and postoperative follow-up of 48 to 87 months (mean, 65.1 months) underwent hemodynamic and cineangiographic evaluations.

RESULTS

There were 11 deaths (17.4%) in the early postoperative period. Of the 52 surviving patients (82.5%), 51 (80.9%) were followed for 1 to 87 months (mean, 42.0 months). Four patients (7.6%) had additional treatment. Of the 15 patients (29.1%) undergoing hemodynamic evaluation, 9 (60%), had mild valvular pulmonary insufficiency and 6 (40%) had moderate insufficiency. Only the right ventricle-to-pulmonary artery pressure gradients and the right ventricular ejection fraction showed statistically significant differences between groups. Right ventricular dimension, although increased in all patients, did not show statistically significant differences.

CONCLUSIONS

Right ventricular outflow tract and pulmonary valve repair in patients with tetralogy of Fallot using a bicuspid porcine pulmonary prosthesis is a simple, reliable procedure with good results in postoperative medium term follow-up.

[Systemic-pulmonary shunts in congenital heart diseases with decreased pulmonary blood flow: critical analysis of the surgical techniques and immediate results]

PURPOSE

To evaluate immediate postoperative results in children with congenital heart disease and decreased pulmonary blood flow who underwent a systemic to pulmonary shunt.

PATIENTS AND METHODS

Sixty-four patients underwent surgery, 46.8% (30) of them males with ages from 1 day to 17 years old. They were divided in three groups: I--13 pts (20.3%) who underwent classical Blalock-Taussig (BT) shunt; II--46 pts (71.8%) who underwent modified BT shunts, 34 of them with polytetrafluoroetylene (PTFE) and 12 of them with umbilical vein shunts; III--5 pts (7.8%) with central anastomosis that were made with three different types of graft; 3 PTFE, umbilical vein and bovine mammary artery in one each. The simultaneous procedures were: section and suture of PDA--2, closure of systemic-pulmonary collaterals--3, pulmonary valvotomy--3, right ventricular outflow patch--3, pulmonary branch stenosis (enlargement)--2.

RESULTS

In group I there were 4 (30.7%) closures, with two immediate reoperation and a total mortality of 30.7%. In group II there were 4 closures (8.6%) and two reoperations with a mortality of 15.2% (7 cases). In group III there was one graft closure and an overall mortality of 80% (4 pts). When analysing deaths due to the shunt itself the mortality rate was respectively 15.3%, 8.6% and 40.0%.

CONCLUSION

Modified BT operation was performed most frequently in our service; it was associated with less closure and mortality than the other types of shunt. It is considered our first alternative for a systemic-pulmonary shunt.