Effect of Corrective or Palliative Procedures on Arterial to End-tidal Carbon Dioxide Pressure Difference in Pediatric Cardiac Surgery

BACKGROUND: The normal small difference (3–5 mmHg) between arterial (partial pressure of carbon dioxide [PaCO(2)]) and end-tidal carbon dioxide pressure (ETPCO(2)) increases in children with congenital heart disease. The present study was conducted to evaluate the effect of corrective or palliative cardiac surgery on this difference (known as DPCO2). PATIENTS AND METHODS: In a prospective study, 200 children (aged <12 years old) candidate for corrective or palliative cardiac surgery were studied. Using arterial blood gas measurement and simultaneous capnography, DPCO(2) was calculated at various intra- and postoperative periods. DPCO(2) values were compared within and between corrective or palliative procedures. RESULTS: Corrective and palliative procedures were carried out on 154 and 46 patients, respectively. Initial DPCO(2) was higher than normal values in corrective or palliative procedures (15.50 ± 13.1 and 10.75 ± 9.1 mmHg, respectively). DPCO(2) was higher in patients who underwent palliative procedure, except early after procedure. The procedure did not have any effect on the final DPCO(2) in palliative group. Although DPCO(2) decrease was significant in the corrective group, it did not return to normal values. Operation time was longer, and the need to inotropic support was higher in corrective procedures; however, longer periods of ventilatory support were needed in the palliative group. Complication rate and Intensive Care Unit stay time were the same in two operation types. CONCLUSIONS: DPCO(2) did not change after palliative cardiac procedures. DPCO(2) decreased after corrective procedures; however, it did not return to normal values at early postoperative period. Thus, DPCO(2) may not have any clinical value in monitoring the quality of corrective or palliative procedures.