A surgeon removed three adjacent bronchopulmonary segments from the left lung of a patient with TB. Almost

Question

A surgeon removed three adjacent bronchopulmonary segments from the left lung of a patient with TB. Almost half of the lung was removed, yet there was no severe bleeding and relatively few blood vessels had to be cauterized (closed off). Why was the surgery so easy to perform?

Answer 1

The vascular supply to each bronchopulmonary segment arrives via a single separate point of entry, the hilus, so it is easy to ligate.  The vessels out in the spongy lung tissue itself are few and tiny.  Each segment is surrounded by connective tissue.