X-Message-Number: 1621 From: (H Keith Henson) Newsgroups: sci.cryonics Subject: Cryonics "wet work" Message-ID: <> Date: Fri, 15 Jan 93 10:50:47 PST There have been several recent postings on highly theoretical areas of cryonics. I have recently been training as a "dire circumstances" surgeon and wrote up a list of how you go about putting in heart bypass plumbing--which is necessary before perfusing patients with cryoprotectants. If the "wet work" phase of cryonics is of interest, read on. The squeamish should hit "D" now. 1. Prep and drape. Clean a large area around midline on the chest with Betadine. Attach drapes with towel clamps leaving a 2 inch wide space on the midline. (Towel clamps hook through the drapes *and* the skin.) 2. Open incision through skin with #10 blade. Cut down to bone with electrocautery. This will leave you and the entire area smelling of incinerated meat for the next two days. However, burning through does seal up the wound edges so they don't leak a lot of perfusate later. 3. Cut through bone on midline from the xiphoid tip to the collar bone with a Stryker (or Sarns) saw. Some of you may know what a Stryker saw looks like, since they are often used to open casts. The Stryker oscillates a half circle of saw through about 20 degrees. It tends to throw little chunks of bone and marrow all over. A Sarns saw (less messy) looks much like a saber saw with a protective guide on the blade. When through, open chest 5-6 inches with a retractor. Rub bone wax into the marrow surfaces of the bone to keep leaking down. 4. Locate heart and remove excess fat from the surface of the pericardium. Pick up and *carefully* split the pericardium on the front surface. 5. "Tent" the pericardium by sewing it in 4-6 places to the skin edges of the wound. This raises the heart and makes the next phase much easier to do. If the patient has a history of heart surgery, there *is* no pericardium, it is hard to identify structures, and the entire procedure is about ten times as hard. (First time I saw this done, it was on a patient with a history of *two* bypass operations. The whole area around the heart was a mess of scar tissue.) 6. Put a purse string suture on the aorta. Using a monofilament type suture with half-inch-long semicircular needles attached, sew a loop *in* (not through!) the wall of the aorta. The aorta is fully four inches down from the chest wall, so use a needle holder (which looks like a blunt pair of hemostats) to make the stitches. Put in 5 or 6 stitches in a circle twice the size of the cannula to be used. Leave 5-6 inches of suture on each end, and thread the ends through a 2 inch long chunk of stiff red rubber tube (made by chopping up a Robinson bladder catheter). Put a hemostat on the tube leaving the suture loose. (The whole complex is called a snare.) 7. Fill an arterial catheter of the appropriate size by submerging it in a bowl of normal saline. Clamp with a tubing occluder. Inspect for bubbles, and get all of them out. 8. Make an incision in the aorta, using a number 11 blade. Start most of the way over on one side of the suture circle with the blunt side of the blade to the outside. Try not to go entirely *through* the aorta. 9. Insert the arterial cannula into the slit you just made. Tighten the purse strings by pulling back on the suture and pushing down on the red rubber. Clamp them tight through the rubber tube. Secure cannula with basket tie or other clips to make sure it will not come out under pressure. 10. Repeat steps 6-9 for the much smaller pressure-measuring cannula. 11. Clamp off half to three quarters of an inch of the tip of the right atrium with an appropriate instrument. (A DeBakey Auricle Clamp or similar is best, but a large curved hemostat will do in a real pinch.) Put purse strings around the heart side of the clamp. Four stitches will do. Thread through red rubber and clamp as above. 12. Cut off the exposed atrium tip. Fill the venous cannula, release clamp, grab the edges with 2-3 hemostats, and insert cannula. May need to open up the hole a little with reversed action on some Mayo scissors. 13. Pull strings up and clamp inside red rubber tube. Secure with basket tie or better. 14. Connect to the perfusion machine tubing. Work bubbles out as you stick the ends of the tubing into the cannulas. 15. For an extra thrill, try this with an AIDS patient--and stick a needle through your glove. Keith Henson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=1621