Late Saturday night in Anchorage, Alaska, a man’s girlfriend cut off his penis and flushed it down the toilet. A municipal worker recovered the penis; surgeons had sewed it back on by morning. How long can you wait before reattaching a severed body part?
A day or two, at least. The man in Alaska was lucky to have his penis sawed off in a frigid climate (though the incident did occur indoors). A severed finger can survive for at least 12 hours in a warm environment and up to a couple of days if refrigerated. Some reports indicate that body parts can survive for as many as four days before being reattached.
Doctors suggest that a severed penis or other body part should be sealed in a plastic bag and placed on ice. Direct contact with the ice can cause frostbite and damage the tissue, and suspending severed body parts in water has been shown to make reattachment more difficult.
Not every part of the body is as resilient as the finger. Muscle tends to have a faster metabolism than other kinds of tissue, so a severed arm or leg will deteriorate more quickly than your pinkie (a full limb must be reattached within six hours to 12 hours). Cartilage has a particularly slow metabolism, so a severed ear or nose can be quite durable. The types of tissues in the penis actually make it an excellent candidate for longer stretches in the ice bucket.
The first step in reattaching a body part is to restore blood flow by reconnecting the arteries. For the procedure to work, the severed tissue must be alive, and the severed arteries must be large enough to manipulate using microsurgical techniques. The blood vessels in the finger are about one or 1.5 millimeters wide (depending on where you cut); vessels in the penis tend to be somewhat bigger and easier to work with.
You also need to reattach the veins, or blood won’t be able to flow out of the severed part. Without a conduit for outflow, the body part will swell, which can cause tissue damage. When veins can’t be sewn up right away, surgeons apply live leeches. A single leech can suck up 10 cubic centimeters of blood from a severed penis; a chemical in its saliva, hirudin, keeps blood from clotting and allows continued drainage.
Tendons, bone, and nerves must also be reattached. In general, the cleaner the cut, the more simple the operation. Ears, which have small arteries and which, when severed, are often ripped off or bitten off, tend to be tricky.
Even in the case of a clean cut, surgeons often remove some tissue to shorten the appendage. When the veins and arteries are stretched, tension on the stitches can jeopardize the procedure; shortening the severed part allows a bit of slack. In situations where significant shortening is undesirable, vein grafts from other parts of the body can provide some leeway.
Explainer thanks Dr. M. Felix Freshwater of the University of Miami School of Medicine.