[Hypoxemia by pulmonary arteriovenous fistulae in childhood: case report.]

Pulmonary arteriovenous fistulae (PAVF) should be investigated in patients with cyanosis of unknown cause. This is a case of cyanosis in a child submitted to pulmonary lobectomy with PAVF.

Male patient, 3 years old, with history of cyanosis without dyspnea since 8 months of age. He presented significant cyanosis, finger clubbing and normal heart auscultation. Chest X-ray showed condensation in the upper half of the left lung. Normal echocardiography and ECG. PaO2 = 28 mmHg in room air and PaO2 = 31.5 mmHg with nasal O2 catheter. Pulmonary arteriovenous fistula was diagnosed through magnetic resonance imaging, with no possibility of embolization. Patient was submitted to upper left lobectomy under general anesthesia associated to spinal anesthesia with morphine and bupivacaine. Selective tracheal tube for the right lung was inserted for monopulmonary ventilation. SaO2 was 59% in room air; at operating room admission 69% (FiO2 = 1.0); after general anesthesia induction 65% (FiO2 = 1.0); during monopulmonary ventilation 58% (FiO2 = 1.0), after lobectomy 98% (FiO2 = 1.0) and 98% at the end of the surgery (FiO2 = 0.6). Extubation was performed one hour after surgery completion. As from the fifth postoperative day patient started presenting progressive SpO2 decrease down to 83% due to increase of another PAVF, which was embolized under general anesthesia. Patient was discharged on the 15th PO day.

In this case, there was poor preoperative response to oxygen therapy, and patient has immediately improved after surgical treatment. However, after surgical resection of the largest PAVF, another fistula increased, thus leading to decrease in postoperative SpO2, reverted by embolization. As the child grows, other pulmonary fistula or fistulae in other organs may be diagnosed, indicating Rendu-Osler-Weber Syndrome.