PHILADELPHIA — Vanessa Brown held her breath and squeezed her eyes shut as she braced herself for the incision along the right side of her chest. Before inserting a chemotherapy port, breast cancer patients typically receive anesthesia or another sedation medication that leaves them too woozy to drive themselves home and requires they have a prearranged ride. Brown’s son, an exterminator, had already missed so much work taking her to appointments that his boss was threatening to fire him. Rather than miss the appointment, Brown decided to forgo sedation and have the procedure with just a loca…