PURPOSE: It has been suggested that the product of ppo FEV1% predicted and ppo DLCO% predicted, the so called predicted postoperative product (PPP), may be a useful value that combines the important elements of both measurements.The purpose of this retrospective study is to evaluate whether abnormal predicted postoperative (ppo) variables and predicted postoperative product (PPP) is useful in predicting postoperative morbidity and mortality following lung resection and whether abnormal diffusion index (DI) is associated with increased postoperative complications following lung resection.
METHODS: Calculation of the ppo variables were performed using preoperative testing data and the extent of resected bronchopulmonary segments. PPP was obtained by multiplying ppo FEV1 by ppo DLCO and measured product (MP) was obtained by multiplying FEV1 by DLCO. DI considered the degree to which the four 3EQ-DLCO values calculated from the four alveolar gas samples deviated from the final 3EQ-DLCO values calculated from the entire alveolar gas sample by measuring the root-mean-square difference of the normalized 3EQ-DLCO values.
RESULTS: Patients with complications had lower ppo FEV1, lower ppo DLCO, lower ppo maximal oxygen uptake (VO2max/kg), and lower ppo mean increase in DLCO% predicted at 70% workload from resting DLCO% predicted ((70%-R)DLCO%). Patients with complications also had lower MP, and lower PPP. Interestingly, patients with complications had higher DI. The ppo (70%-R)DLCO% was the best preoperative predictors of postoperative complications; a cut-off limit of 14% was the best index to identify complications.
CONCLUSION: Patients with ppo (70%-R)DLCO% less than 14% have increased complication rates following lung resection.
CLINICAL IMPLICATIONS: In the present study, we have shown that the ppo values were good predictors for postoperative complications also, and ppo(70%-R)DLCO% like (70%-R)DLCO% was the best predictor. Like our pneumonectomy study, MP and PPP were good predictors also. Interestingly, in present study, we have shown that DI was also good predictor, and DI deteriorates in patients with complications and DI improves in patients without complications during exercise.
DISCLOSURE: Jeng-Shing Wang, No Financial Disclosure Information; No Product/Research Disclosure Information