Curr Health Sci J, vol. 44, no. 3, 2018

Prediction of Post Operative Complication in Patients with Valvular Heart Surgery Based on O2 Challenge Test and A-A Gradient

[Original Paper]


(1)Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran,
(2)Iran University of Medical Sciences, Tehran, Iran


Patients with valvular heart diseases may have more physiological lung derangements and therefore at current study we studied correlation of O2 challenge, A-AG tests and spirometry values of patients who underwent valve surgery on post op respiratory complications. Method: 180 adult patients undergoing non-emergency cardiac valvular surgery were studied. On operating room all patients had arterial blood gas profile (ABG) at room air, 20 minutes after putting on ventilator with 100% O2, and pump oxygenator. Pulmonary function tests, alveolar Oxygen Pressure, mean Arterial pressure of carbon dioxide and alveolar-arterial gradients measured. Results: FEV1, FVC and FEV1/FVC%, pressure of arterial Blood Gasses (O2 and CO2) with fraction of inspired oxygen of 100% and air (PO2-100 and PO2-air), were significantly different between patients with POPC and patients without POPC (p-value <0.05). Indeed PO2-100 and PO2-air were significantly lower in patients with POPC. A-AG100 (p-value: 0.02) and A-AG21 (p-value: 0.02) were significantly higher in patients with POPC in comparison with patients without POPC. The AUC of A-AG100 for predicting POPC was 0.59 (95% confidence interval (CI) 0.51-0.67). The optimal cut point of A-AG100 was 311 and showed evidence of high relatively sensitivity of 80% and a negative predictive value of 61%. Conclusion: Valvular heart surgery still has significant post op complication and mortality. There is significant correlation between A-AG100, A-AG21 percent, PaO2100, and FEV1/FVC with post op complications in these patients. We recommend measurement of these values in pre op evaluation of patient who need cardiac surgery.

Post op complications, valvular heart diseases, pulmonary function tests, O2 challenge tests, alveolar arterial gradients

Behshid Ghadrdoost,, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran

DOI 10.12865/CHSJ.44.03.10 - Download PDF