Final answer:
Complications from a tourniquet left on the arm for over 1 minute include changes in blood pressure, loss of consciousness, cardiac arrest, and potential tissue damage due to disrupted blood circulation.
Step-by-step explanation:
When a tourniquet is left on the arm for over 1 minute, it can result in a variety of complications due to prolonged obstruction of blood flow. This may lead to changes in blood pressure, possible loss of consciousness, and in severe cases, cardiac arrest. The vascular spasm response is the body's initial reaction to a vessel injury, causing the vessels to constrict in order to reduce blood flow and minimize bleeding. However, when a tourniquet is applied for too long, it disrupts normal blood circulation, which in turn can affect the delivery of oxygen and nutrients to the tissues, thereby causing tissue damage and other systemic issues.