[Intra-operative pulmonary air embolism caused by left subclavian vein injury, during cervical tumor resection: a case report].

A 73-year-old male developed intra-operative pulmonary air embolism during cervical tumor resection under general anesthesia. Just after unexpected bleeding (about 700 ml) from the left subclavian vein, PetCO2 decreased suddenly from 32 mmHg to 22 mmHg, SpO2 decreased from 99% to 87% and systolic blood pressure decreased from 110 mmHg to 80 mmHg. Nitrous oxide was discontinued immediately, and blood transfusion and continuous infusion of dopamine (5 micrograms.kg-1.min-1) were started. In spite of the recovery of PetCO2 and blood pressure, hypoxemia (PaO2 54 mmHg at 100% oxygen) continued. The operation was discontinued and the patient was transferred to the intensive care unit. Postoperative chest radiograph showed findings of pulmonary edema. We suspected that the air embolism would have been induced by spontaneous respiration associated with the injury of the subclavian vein. Pulmonary edema may have been induced by pulmonary embolism and volume overload for the acute hemorrhage. The intra-operative pulmonary air embolism can be accelerated by use of nitrous oxide and spontaneous respiration.