Generally, a TPA will accept to pay only part of the sum required for the treatment of the patient, and settles the final bill with the hospital after the patient has been treated. In some cases if you exceed your policy assured sum, you will be required to pay the excess amount. If your policy does covers the required sum, and your TPA has not sanctioned a sum large enough to cover the initial cost of your treatment the hospital will ask for the sum to be increased.