Editing Rapid sequence induction (section)

=== Pre-Intubation Steps ===
Rapid sequence intubation refers to the pharmacologically induced [[sedation]] and neuromuscular [[paralysis]] prior to intubation of the trachea. The technique is a quicker form of the process normally used to induce [[general anesthesia]]. A useful framework for describing the technique of RSI is the "seven Ps".<ref>{{cite web|vauthors=Cooper A|title=Rapid Sequence Intubation – A guide for assistants|url=http://www.scottishintensivecare.org.uk/education/RSI%20brochure.pdf|work=Scottish Intensive Care Society Education|publisher=NHS – Education for Scotland|access-date=31 March 2013|archive-date=24 January 2013|archive-url=https://web.archive.org/web/20130124225751/http://www.scottishintensivecare.org.uk/education/RSI%20brochure.pdf|url-status=dead}}</ref>
[[File:Prehospital RSI training.jpg|thumb|Prehospital RSI training using a checklist]]

==== Preparation ====
The patient is assessed to predict the difficulty of intubation. Continuous physiological monitoring such as [[Electrocardiogram|ECG]] and [[pulse oximetry]] is put on the patient. The equipment and drugs for the intubation are planned, including the endotracheal tube size, the laryngoscope size, and drug dosage. Drugs are prepared in syringes. [[Intravenous]] access is obtained to deliver the drugs, usually by placing one or two IV [[cannulae]].<ref>{{Citation |last1=Schrader |first1=Matthew |title=Tracheal Rapid Sequence Intubation |date=2022 |url=http://www.ncbi.nlm.nih.gov/books/NBK560592/ |work=StatPearls |place=Treasure Island (FL) |publisher=StatPearls Publishing |pmid=32809427 |access-date=2022-11-10 |last2=Urits |first2=Ivan}}</ref>

==== Preoxygenation ====
The aim of preoxygenation is to replace the nitrogen that forms the majority of the [[functional residual capacity]] with oxygen. This provides an oxygen reservoir in the lungs that will delay the depletion of oxygen in the absence of ventilation (after paralysis). For a healthy adult, this can lead to maintaining a blood [[oxygen saturation]] of at least 90% for up to 8 minutes.<ref>{{cite journal | vauthors = Benumof JL, Dagg R, Benumof R | title = Critical hemoglobin desaturation will occur before return to an unparalyzed state following 1 mg/kg intravenous succinylcholine | journal = Anesthesiology | volume = 87 | issue = 4 | pages = 979–982 | date = October 1997 | pmid = 9357902 | doi = 10.1097/00000542-199710000-00034 | s2cid = 27271368 | doi-access = free }}</ref> This time will be significantly reduced in obese patients, ill patients and children. Preoxygenation is usually performed by giving 100% oxygen via a tightly fitting face mask. Preoxygenation or a maximum of eight deep breaths over 60 seconds resulting in blood oxygenation is not different from that of quiet breathing volume for 3 minutes.<ref>{{Cite web | url=http://anesthesiageneral.com/preoxygenation/ | title=Preoxygenation| date=2010-10-04}}</ref>

Newer methods of preoxygenation include the use of a nasal cannula placed on the patient at 15 LPM at least 5 minutes prior to the administration of the sedation and paralytic drugs. High flow nasal oxygen has been shown to flush the nasopharynx with oxygen, and then when patients inspire they inhale a higher percentage of inspired oxygen. Small changes in FiO2 create dramatic changes in the availability of oxygen at the alveolus, and these increases result in marked expansion of the oxygen reservoir in the lungs prior to the induction of apnea. After apnea created by RSI the same high flow nasal cannula will help maintain oxygen saturation during efforts securing the tube (oral intubation).<ref name="pmid28684195">{{cite journal | vauthors = Binks MJ, Holyoak RS, Melhuish TM, Vlok R, Bond E, White LD | title = Apneic oxygenation during intubation in the emergency department and during retrieval: A systematic review and meta-analysis | journal = The American Journal of Emergency Medicine | volume = 35 | issue = 10 | pages = 1542–1546 | date = October 2017 | pmid = 28684195 | doi = 10.1016/j.ajem.2017.06.046 | s2cid = 8624609 }}</ref><ref name="pmid28647137">{{cite journal | vauthors = Pavlov I, Medrano S, Weingart S | title = Apneic oxygenation reduces the incidence of hypoxemia during emergency intubation: A systematic review and meta-analysis | journal = The American Journal of Emergency Medicine | volume = 35 | issue = 8 | pages = 1184–1189 | date = August 2017 | pmid = 28647137 | doi = 10.1016/j.ajem.2017.06.029 | s2cid = 2383170 }}</ref> The use of nasal oxygen during pre-oxygenation and continued during apnea can prevent hypoxia before and during intubation, even in extreme clinical cases.<ref>{{Cite web | vauthors = Levitan R | url=http://www.epmonthly.com/archives/features/no-desat-/ | title=No Desat! | work = Emergency Physicians Monthly | date=9 December 2010 }}</ref>

==== Pretreatment ====
Pretreatment consists of the medications given to specific groups of high-risk patients 3 minutes before the paralysis stage with the aim of protecting the patient from the adverse effects of introducing the laryngoscope and endotracheal tube. Intubation causes increased [[Sympathetic nervous system|sympathetic]] activity, an increase in [[intracranial pressure]] and bronchospasm. Patients with [[reactive airway disease]], increased intracranial pressure, or cardiovascular disease may benefit from pretreatment. Two common medications used in the pretreatment of RSI include Lidocaine and Atropine. Lidocaine has the ability to suppress the cough reflex which in turn may mitigate increased intracranial pressure. For this reason Lidocaine is commonly used as a pretreatment for trauma patients who are suspected of already having an increase in intracranial pressure. Although there is not yet definitive evidence to support this, if proper dosing is used it is safe. The typical dose is 1.5&nbsp;mg/kg IV given three minutes prior to intubation.<ref name="pmid21719592">{{cite journal | vauthors = Hampton JP | title = Rapid-sequence intubation and the role of the emergency department pharmacist | journal = American Journal of Health-System Pharmacy | volume = 68 | issue = 14 | pages = 1320–30 | date = July 2011 | pmid = 21719592 | doi = 10.2146/ajhp100437 }}</ref> Atropine may also be used as a premedication agent in pediatrics to prevent bradycardia caused by hypoxia, laryngoscopy, and succinylcholine. Atropine is a parasympathetic blocker. The common premedication dose for atropine is 0.01–0.02&nbsp;mg/kg.

==== Paralysis with induction ====
With standard intravenous induction of general anesthesia, the patient typically receives an [[opioid]], and then a hypnotic medication. Generally the patient will be manually ventilated for a short period of time before a [[neuromuscular block]]ing agent is administered and the patient is intubated. During rapid sequence induction, the person still receives an IV opioid. However, the difference lies in the fact that the induction drug and neuromuscular blocking agent are administered in rapid succession with no time allowed for manual ventilation.{{citation needed|date=January 2022}}

Commonly used hypnotics include [[Sodium thiopental|thiopental]], [[Propofol]] and [[etomidate]]. The [[Neuromuscular-blocking drug|neuromuscular blocking agents]] paralyze all of the [[Skeletal striated muscle|skeletal muscles]], most notably and importantly in the [[oropharynx]], [[larynx]], and [[Thoracic diaphragm|diaphragm]]. [[Opioid]]s such as [[fentanyl]] may be given to attenuate the responses to the intubation process ([[tachycardia|accelerated heart rate]] and increased [[intracranial pressure]]). This is supposed to have advantages in patients with [[Ischaemic heart disease|ischemic heart disease]] and those with [[brain injury]] (e.g. after [[traumatic brain injury]] or [[stroke]]). [[Lidocaine]] is also theorized to blunt a rise in intracranial pressure during laryngoscopy, although this remains controversial and its use varies greatly. Atropine may be used to prevent a reflex bradycardia from vagal stimulation during laryngoscopy, especially in young children and infants. Despite their common use, such adjunctive medications have not been demonstrated to improve outcomes.<ref name=Neilipovitz2007>{{cite journal | vauthors = Neilipovitz DT, Crosby ET | title = No evidence for decreased incidence of aspiration after rapid sequence induction | journal = Canadian Journal of Anaesthesia | volume = 54 | issue = 9 | pages = 748–764 | date = September 2007 | pmid = 17766743 | doi = 10.1007/BF03026872 | doi-access = free }}</ref>

==== Positioning ====
Positioning involves bringing the axes of the mouth, pharynx, and larynx into alignment, leading to what's called the "sniffing" position.  The sniffing position can be achieved by placing a rolled towel underneath the head and neck, effectively extending the head and flexing the neck. You are at proper alignment when the ear is inline with the sternum.<ref>{{cite book|title=Nancy Caroline: Emergency Care in the Streets 7th Ed.|year=2013|publisher=Jones & Bartlett Learning|pages=780}}</ref>

As described by [[Brian Arthur Sellick]] in 1961, [[cricoid pressure]] (alternatively known as Sellick's maneuver) may be used to occlude the esophagus with the goal of preventing aspiration.

==== Placement of tube ====
During this stage, [[laryngoscopy]] is performed to visualize the [[glottis]]. Modern practice involves the passing of a "Bougie", a thin tube, past the [[Vocal folds|vocal cords]] and over which the endotracheal tube is then passed.  The bougie is then removed and an inbuilt cuff at the end of the tube is inflated, (via a thin secondary tube and a syringe), to hold it in place and prevent aspiration of stomach contents.

The position of the tube in the trachea can be confirmed in a number of ways, including observing increasing end tidal carbon dioxide, auscultation of both lungs and stomach, chest movement, and misting of the tube.

==== Postintubation management ====
Mispositioning of the [[Tracheal tube|endotracheal tube]] (in a bronchus, above the glottis, or in the esophagus) should be excluded by confirmation of end tidal {{CO2}}, auscultation, fogging of the endotracheal tube, and observation of bilateral chest rise.