Pengaruh kapasitas vital paksa, hipertensi pulmonal, jumlah perdarahan, transfusi darah, jumlah cairan dan lokasi segmen vertebra terhadap lama ventilasi mekanik pascaoperasi koreksi skoliosis pendekatan posterior = Effect of forced vital capacity pulmonary hypertension amount of bleeding amount of intraoperative fluid blood transfusion and location of vertebrae involved against duration postoperative mechanical ventilation in posterior approach scoliosis surgery