What is cough syncope?

Yes: Cough syncope is passing out in relation to coughing. It is caused by a drop in blood pressure which is caused by the cough stimulating the vagus nerve which leads to the loss in blood pressure. It is the same mechanism as the common "fainting spell" some people have.

Most common cause: Cough causes an increase in chest pressure. This causes a pressure increase in the skull. High chest pressure decreases venous blood return and cardiac output. Increased chest pressure is sent to the circulation, causing a reflex-vasodilatation. The combination of increased pressure in the skull and the lowered arterial pressure results in a perfusion standstill in the brain resulting in feinting.