General anaesthesia may be safely undertaken in patients with an acute porphyria (Acute Intermittent Porphyria, Variegate Porphyria or Hereditary Coproporphyria) providing care is taken to select anaesthetic agents that are known to be safe.
In those patients in whom it is necessary to proceed with anaesthesia before a definitive diagnosis is made it is best to treat the patient as if they were affected (Link to diagnostic page).
The patients at most risk from a general anaesthetic are those whose porphyria is, or has been recently active.
No drug should be withheld from a porphyria patient facing a serious or life threatening emergency and conversely inclusion of a drug does not guarantee that it will be safe in all circumstances.
General measures
Patients should include avoid a prolonged fast both preoperatively and postoperatively.
Stress should be minimised by effective pre-medication and postoperative analgesia.
Post operative complications especially infection should be treated aggressively (see Antibiotic treatment guidelines)
Drugs used During Anaesthesia
The table below has been compiled from information in the literature and is intended for guidance only.
Some drugs cannot be classified due to lack of information or because there is conflicting information in the literature.
Inclusion of a drug does not guarantee that it will be safe in all circumstances.
For more detailed information the review by James and Hift (Br J. Anaes. Vol 85(1): 143-53) may be helpful.
Safe | Probably or possibly safe | Unsafe or no data | |
Induction | Propofol | Ketamine Midazolam |
Thiopental Etomidate |
Inhalational | Nitrous oxide Enflurane |
Isoflurane Sevoflurane |
Fluroxene methoxyflurane |
Paralysis | Suxamethonium Muscle relaxants non-depolarising Vercuronium Atracurium Mivacurium Cisatracurium |
Alcuronium |
|
Analgesia | Fentanyl Opiates (morphine diamorphine, pethidine) |
Oxycodone Nalbuphine |
Pentazocine |
Sedatives/Antiemetics | Phenothiazines Domperidone Temazapam Triazolam |
Nitrazepam | |
Hypotension | Adrenaline Noradrenaline |
||
Other | Atropine Alpha agonists Beta agonists Beta blockers Magnesium Neostigmine Phentolamine |
Verapamil Flumazenil Naloxone |
