Porphyria Educational Services Bulletin

Vol. 2 No. 31                                                                             August 6, 2000 

For many surgeries or medically procedures today conscious sedation is used.

 

In terms of a porphyria patient undergoing the use of conscious sedation, selection

of proper anesthesia is mandated.

 

Conscious sedation is achieved by administering pharmacological agents.

 

The most highly used way  of administration is intravenous (IV), although
medications may be given orally (P0), rectally, intramuscular (IM), subcutaneously (SQ),
or nasally. The most commonly used agents are benzodiazepines, narcotics,
barbiturates, and certain hypnotics (such as chloral hydrate).

 

The pharmaceuticals  used depend on the type, duration and intensity of the procedure.

 

Physicians and nurses who do not have privileges in anesthesiology should not administer
drugs classified as anesthetic agents, including but not limited to, ketamine, sodium
pentothal, methohexital, propofol, etomidate and nitrous oxide, for the intent of conscious
sedation.

 

Differences in patients' health status with variable ability to metabolize medications
should be considered when selecting and administering the medications.  Any drug that is metabolized

through the liver should not be used in an acute hepatic porphyria patient.

 

The anethesist  is responsible for validating the physician's order, obtaining the medications,
and assuring administration of medications according to the hospital's policy.
Such procedure  includes the right medication in the right dose, to the right patient,
over the right time frame, through the right route.

 

The person administering the anesthesia must adhere to all National, State and
Hospital guidelines when administering any IV medication.

 

Any inconsistencies between physician orders and guidelines should be
resolved prior to administering the medications.

 

All medications, including reversal agents, should be documented on the
appropriate patient permanent record.

 

Most usually non-anesthesia personnel may administer only benzodiazepines such as diazepam
(Valium) and midazolam (Versed), and narcotics such as fentanyl (Sublimaze), morphine, or meperidine (Demerol).
 

Conscious sedation is achieved using the same medications and
delivery methods used for anesthesia and deep sedation.

 

Health care providers monitoring the sedated patient must demonstrate a knowledge of anatomy,
physiology, dysrhythmia recognition, complications related to conscious sedation, and a
knowledge of the pharmacology of the medications and the reversal agents.

 

Such health care professionals  must also have the skills necessary to assess,
diagnose, and treat any complications that may arise.

 

Midazolam (Versed) is a short acting benzodiazepine CNS depressant.
It is indicated for conscious sedation prior to short diagnostic or surgical procedures,
either alone or with a narcotic. Versed may be administered IV, IM, P0, rectally, or
nasally. The most common route of administration is IV.

 

Midazolam [Versed]  should not be used on patients with known benzodiazepine hypersensitivity or acute narrow-angle glaucoma. Adverse reactions from IV administration include hiccups, nausea, vomiting, over sedation, headache, coughing, and pain at the injection site.

 

Narcotics are also used during surgery or medical procedure where pain can occur.

 

Narcotics are naturally occurring or synthetic opioids that act to provide analgesia, sedation, and elevate the pain threshold. They may be classified as agonists, mixed agonists-antagonists, or partial agonists by their activity at the opioid receptors.

 

Fentanyl (sublimaze) is a synthetic opioid. It is indicated for analgesic action of short duration in procedures such as endoscopies.

 

Reversal Agents are another factor which needs to be considered in terms of the porphyric patient.

 

Reversal agents are drugs that counteract the effects of other drugs. The reversal agent used for benzodiazepines is
flumazenil (Romazicon), and the reversal agent used for narcotics is naloxone (Narcan).

 

Flumazenil is a benzodiazepine antagonist. It competes for receptor sites thereby reducing or reversing the effects of the benzodiazepine. It should be used with extreme caution, and never in porphyria patients whoexperience seizures.

 

Naloxone (Narcan) is a pure narcotic antagonist. It competes for the receptor sites thereby reversing the effect of the narcotic. It is important to note that all opioid effects are reversed in parallel.

 

Baseline vital signs, oxygen saturation level, heart rhythm, and level of consciousness are the minimum assessment parameters obtained and documented prior to sedation. During the medication administration, the sedating period and the recovery phase, these parameters should be monitored and documented at least every five minutes. The anesthesist should immediately
report to the physician any variations from baseline.

 

Documentation  of sedation and other pharmaceutical in porphyria patients should include:

Dosages, route, time and effect of all drugs used ;Type and amount of fluids administered, including blood and blood products, monitoring devices or equipment used
Heart rate, rhythm, blood pressure, respiratory rate, oxygen saturation, and level of consciousness
Interventions and the patients response to the interventions
Untoward or significant patient reactions and their resolution or outcome

 

The patient must be continuously monitored from the start of conscious sedation until the time discharge criteria are met.

 

Michelle G. RNA, BS, MNS