Comprehensive guide to preparing for rapid sequence induction and intubation
Rapid sequence induction (RSI) and tracheal intubation is the process of rapidly inducing hypnosis followed by paralysis to facilitate the passing of an endotracheal tube. This is used when there is high risk of gastric regurgitation.
A RSI is a high risk procedure and adequate check and preparation must be performed. PEACH is a useful mnemonic to remember the steps in preparing for RSI:
Optimal positioning of the patient for RSI and tracheal intubation is intended to:
Approximately 25% of RSIs undertaken in the emergency department include stabilisation of the spine, requiring the patient to be managed in a supine position. This is not ideal for achieving optimal pre-oxygenation or the best view at laryngoscopy. Therefore, in almost all other cases the patient is placed in an optimum position.
When lying in the supine position it is difficult for a patient to take large breaths. Posterior lung tissue becomes prone to atelectasis, reducing the number of alveoli available for pre-oxygenation. This decreases the reservoir of oxygen contained with the lungs and therefore reduces the period an apnoeic patient is likely to maintain arterial blood oxygen saturation above 92% (an effect compounded by obesity or pregnancy).
Managing the patient in a head-up or reverse Trendelenburg position can significantly improve this situation as this displaces weight from the anterior chest wall decreasing the load on the thoracic cavity and reducing the pressure of intra-abdominal contents on the diaphragm. Both of these factors can increase lung functional residual capacity and reduce atelectasis thereby improving the effectiveness of pre-oxygenation.
However, some hypotensive patients may not tolerate this and the effect on cerebral perfusion must be considered - consider concurrent leg elevation or fluid/inotropic support.
Correct positioning of the patient's head and neck improves the view of the larynx at laryngoscopy and the likelihood of successful intubation. During laryngoscopy, alignment of the oral, pharyngeal and laryngeal axes in the 'sniffing the morning air' position can provide a clear view from the incisors to the laryngeal inlet.
Using the ramped position (where the external auditory meatus is on the same horizontal plane as the sternal notch, achieved with the trolley back elevated and a pillow under the occiput, by using proprietary ramp devices or by pillows alone) will facilitate both pre-oxygenation and intubation and has been shown to be of benefit in obese and non-obese patients.
Prepare and check thoroughly all equipment before undertaking any anaesthetic.
To achieve optimal pre-oxygenation give high-flow oxygen to the patient in all but the most unusual circumstances; use a breathing system that will maximise oxygen delivery.
The minimum requirement is high flow oxygen (15 L/min) through a well fitting mask with an oxygen reservoir.
Pre-oxygenation can be achieved using a self-inflating bag mask but the practitioner has to maintain a good mask seal during the stressful moments of preparing for RSI.
An effective alternative is an anesthetic breathing system, such as a Mapleson C circuit; these can deliver high oxygen concentrations, require minimal inspiratory effort and the oxygen reservoir bag provides a clear view of respiratory effort; however a higher level of skill is required to use the device safely and effectively.
In patients with significant lung disease, pre-oxygenation may be achieved optimally using non-invasive respiratory support, particularly if the patient requires this treatment to maintain oxygenation prior to RSI.
The minimum recommended standards of monitoring which are required whenever anaesthesia is administered:
Pre-procedural checklists and team briefings reduce errors and untoward incidents. Use intubation checklists for all intubations of critically ill patients and identify backup plans.
Prior to RSI it is wise to briefly review the patient's history. The pertinent points can be remembered using the mnemonic AMPLE:
Ensure there are two functioning IV lines before giving any anaesthetic drugs.
An appropriately experienced individual should be present before undertaking advanced airway management in a critically ill patient. If RSI is anticipated, summon expert help immediately.
RSI outside the operating room requires a minimum of three or four staff.