It’s amazing how many times Winky has recieved damage to major organs (i.e., his spleen) and still survived. A: He happens to be very resilient (to the point of ridiculousness), B: As Johanan suggested, Dr. (They should take away his degree on grounds of malpractice!) Mel is using clones, or C: This is just a comic strip, and therefore not real, so don’t waste your time trying to rationalize it.
This reminds me of that one strip series that was a parody of The Lord of the Rings, The Wizard of Oz, and a few other movies/ TV series.
They met a talking, walking tree, and over the course of several strips, reduced him to the size of a rat. Then Cliff needed toothpicks.