Why is a patient chest shaved before defribrillation?

A patient's chest is shaved before defibrillation to ensure proper adherence of the defibrillator pads to the skin, which facilitates effective delivery of the electrical shock. Shaving removes hair that could impede contact and reduce the conductivity of the pads, potentially leading to ineffective defibrillation. Additionally, a clean surface helps prevent skin burns and ensures better monitoring of the patient's heart rhythm.