General Anaesthesia in the Acute Porphyrias

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