Porphyria Educational Services
PORPHYRIA EDUCATIONAL SERVICES BULLETIN Vol. 1 No. 44
October 24, 1999 ~ FOCUS: Anesthesia and the Porphyrias
Safety of general anesthesia and
surgery in the acute hepatic porphyrias has long been a
concern of the majority of porphyric patients.
Porphyric patients with the acute hepatic types of porphyria are denied essential operations because of concern that general anesthesia and surgery will precipitate a life threatening porphyric crisis. In a study conducted at the Western Infirmary in Glasgow, Scotland, a special study assessed the safety of surgery under general anesthesia in acute porphyric patients.
The study by Dover, McColl, Moore and Plenderleith which was reported in 1994 issue of "Gut" medical journal, told of a combined prospective and retrospective case note study, with a biochemical study, which was conducted in 25 patients with acute hepatic porphyria undergoing 38 surgical operations. Clinical outcome measures were survival and occurrence of porphyric crisis after surgery.
The study the porphyric patients were assessed by measurement of the preoperative 24 hour excretion of the heme precursors delta amino- laevulinic acid (ALA) and porphobilinogen (PBG)
There were no deaths or crises after 29 operations in 19 patients who were known to have porphyria before their surgery, and therefore given only appropriate drugs. These operations include such major procedures as mitral valve replacement, hip replacement, coronary artery grafting, cholecystectomies, and renal transplantation.
In eight of these patients the urinary excretion of ALA and PBG were studied, and showed no sustained postoperative increase. Nine operations were performed in eight patients before the diagnosis of porphyria was known and who thus received routine anesthetic agents. The conclusion of the Scottish study is that even the most major surgery can be undertaken safely in patients with porphyria. The risk therefore is for undiagnosed cases.
Presently in the United States the anesthesia Versed [Midazolam] isbeing offered of the anesthesia of choice for most surgeries and especially for porphyric patients. It ha a very high safety record. Most people do not even realize they hav been asleep let alone drugged. There are no noticeableside effects or after affects.
Versed is also an anesthesia that works well together with the pain medication fentanyl which can be administered intravenously as well.
Surgery for porphyic patients is no longer the problem it once was.The real challenge is now to have the right anesthesia for the latent porphyricpatients who is unaware of his or her condition.