You only enter expenses that YOU paid out of pocket.  The money you are waiting for from the other driver does not go on your tax return.

MEDICAL EXPENSES

The medical expense deduction has to meet a rather large threshold before it can affect your return. The amount of medical (including dental, vision, etc.)  expenses that will count toward itemization is the amount that is OVER 7.5% of your adjusted gross income. You should only enter the amount that you paid in 2019—do not include any amounts that were covered by insurance or that are still outstanding. Of course, your medical expenses plus your other itemized deductions still have to exceed your standard deduction before you will see a difference in your tax due or refund.

To enter your medical expenses go to Federal>Deductions and Credits>Medical>Medical Expenses

You have a choice:

1. Don't claim medical expenses, because you know you will be reimbursed, eventually.  If for some reason, the reimbursement falls thru, you can file an amended 2019 return in the future.

2.  Claim a medical deduction on your 2019 tax return.  When you receive the reimbursement, in the future, you will have to claim a portion (the net deductible amount on your 2019 return) of it as misc. income. 

You would have to do the math to see if one way was better than the other. That can be complicated. the medical deduction is only an itemized deduction subject to a 7.5% of AGI threshold.

What medical question exactly? What are your medical expenses for 2019? It is whatever you paid out of pocket. If you paid by credit card in 2019, that counts too. However, if you claim a deduction and get reimbursed, then that is income.

@jvcervantes