Rapid sequence induction

Rapid Sequence Induction (RSI) is an advanced medical procedure, designed for the expeditious intubation of the trachea of a patient. RSI is generally used for patients who have an increased risk of aspirating stomach contents into the lungs due to a current disease process.

Technique

The technique, RSI, strictly refers to the sedation and induction of paralysis prior to an intubation procedure. The technique is a quicker form of the process normally used to "induce" a state of general anesthesia. The difference between an RSI and standard anaesthetic induction is that the anaesthetist does not wait to see the effect of the drugs. It uses drugs to rapidly allow an endotracheal tube to be placed between the vocal cords, while the cords are being visualized via a laryngoscope. The neuromuscular blocking agents interfere the patient's smooth muscles in the oropharynx, larynx, and diaphragm. Once the endotracheal tube has been passed between the vocal cords, a cuff is inflated around the tube in the trachea and the patient can then be artificially ventilated. RSI involves pre-oxygenating the patient with a tightly-fitting oxygen mask, followed by the sequential administration of pre-determined doses of a hypnotic drug and a rapid-acting neuromuscular blocker. Hypnotics used include thiopental, propofol and etomidate. Neuromuscular-blocking drugs used include suxamethonium (also called succinylcholine) and rocuronium. [http://www.ispub.com/ostia/index.php?xmlFilePath=journals/ijeicm/vol4n1/rapid.xml#documentHeading-VI.Pharmacology Rapid Sequence Induction for Prehospital Providers ] ] Other drugs may be used in a "modified" RSI. When performing endotracheal intubation, there are several adjunct medications available. No adjunctive medications, when given for their respective indications, have been proven to improve outcomes. [David T. Neilipovitz, Edward T. Crosby: "No evidence for decreased incidence of aspiration after rapid sequence induction", in: "Canadian Journal of Anesthesia" 54, 9, 2007, S. 748-764 [http://www.ncbi.nlm.nih.gov/pubmed/17766743 Abstract] , http://www.cja-jca.org/cgi/content/full/54/9/748 ] Opioids such as alfentanil or fentanyl may be given to attenuate the responses to the intubation process (tachycardia and raised intracranial pressure). This is supposed to have advantages in patients with ischemic heart disease and those with intra-cerebral haemorrhage (e.g. after traumatic head injury or stroke). Lidocaine is also theorized to possibly decrease a rise in intracranial pressure during laryngoscopy, although this remains controversial and its use varies greatly. Atropine may be used by many physicians to prevent a reflex bradycardia during laryngoscopy, especially in young children and infants.

Requirements

The clinician that performs RSI must be skilled in intubation. Failure to intubate means needing to ventilate by mask. In case the patient's airway may still not be secured with appropriate airway management means certain death.

The clinician that performs RSI must be knowledgeable about the drug administered. The clinician must understand the to time onset of action of a drug and the required dosage. Otherwise, the clinician risks paralyzing a fully conscious patient. The clinician must also be aware of possible side effects of the drugs such as malignant hyperthermia. The clinician must use sound judgment in selecting which drug is to be used and the amount to be used.

Meticulous preparation and planning is necessary. Back-up plans must be in place. Plans may include the option to move to a non-visualized such as the combitube, or laryngeal mask airway. A mandatory emergency back-up plan is an emergency cricothyrotomy

This procedure is extremely dangerous. A clinician removes all ability of the patient to breathe or to maintain a patent airway. For this purpose, most prehospital paramedic ambulances are required to have two paramedics in the patient compartment when performing this procedure.

Mnemonic

A mnemonic for performing RSI is the seven Ps

# Preparation-- Prepare all necessary equipment, drugs and back-up plans
# Preoxygenation-- with 100% oxygen
# Premedication-- depending on the patient, just the hyponotic agent
# Paralyze-- suxamethonium or rocuronium
# Pass the tube-- Visualize the tube going through the vocal cords
# Proof of placement-- Using reliable confirmation method
# Post intubation care-- Secure the tube, ventilate

Conclusion

This procedure is usually performed by Anesthesiologist in Surgery and by Emergency Room Dcotors in the emergency department. It is also performed in the prehospital setting. The prehospital clinician that performs this procedure is a person trained to the Paramedic level.

References

External links

* cite journal
last = Pousman
first = Robert M.
authorlink =
title = Rapid Sequence Induction for Prehospital Providers
journal = The Internet Journal of Emergency and Intensive Care Medicine
volume = Volume 4
issue = Number 1
publisher = Internet Scientific Publications, LLC
date = 2000
url = http://www.ispub.com/ostia/index.php?xmlFilePath=journals/ijeicm/vol4n1/rapid.xml#documentHeading-VI.Pharmacology
format = HTML
issn = 1092-4051

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