This invasive technique allows for blind placement of an endotracheal tube (ETT) over a guidewire or catheter that is inserted percutaneously at the level of the cricothyroid membrane (CTM) or cricotracheal ligament. The wire is then directed retrograde up into the pharynx, then into the mouth or nose. The procedure was originally described with the use of a red rubber catheter introduced through a tracheostomy and has evolved to include the use of a guidewire placed percutaneously and pulled retrograde, then placed through the lumen or Murphy eye of the ETT.¹,² Retrograde intubation (RI) can be performed with just a guidewire. However, because an ETT has the potential to move laterally about a thin wire, and then catch on the aryepiglottic fold or arytenoid cartilage as it is inserted, the technique frequently incorporates a guide catheter placed over a wire before the ETT is inserted.³ The retrograde wire may also be retracted from the nose, allowing for nasotracheal intubation. RI has been used successfully in pediatric difficult airways as well as those of adults.²

RI was first described by Butler and Cirullo⁴ in 1960 and has since been used effectively in patients with normal to severely traumatized airways. The main benefits of this technique over fiberoptic intubation or the newer video laryngoscopic techniques are that blood or secretions in the pharynx do not detract from successful intubation¹,⁵ and that the equipment needed is inexpensive and readily available. Although there are commercially available kits for RI, successful implementation of this technique has been described with equipment as simple as a Touhy needle and an epidural catheter.⁶ RI has been useful in overcoming difficult airway anatomy in both the emergency department (ED) and the operating room (OR).⁷,⁸ However, the technique has not been widely applied in either setting. Data regarding its application are limited to case reports and case series. RI has been described anecdotally in several difficult airway situations, including management of patients with obstructive sleep apnea, facial trauma/burns, large oral cancers, spinal cord injury, spine and joint disorders, oral infections, pharyngeal edema, angioedema, laryngeal carcinomas, and airway anomalies.²,⁹,¹⁰ Barriot described its use by emergency physicians in the field, where it was employed successfully in 13 patients with severe maxillofacial trauma who could not be intubated by direct laryngoscopy in the prehospital setting, and in another 6 patients in whom the technique was used electively.⁵ Its use has also been described perioperativley when fiberoptic intubation was either not available or not feasible with success in 24 of 24 patients.⁶ In the hands of those who use the technique frequently, RI appears to have a high success rate. Of 383 applications described in the literature by 1996, the technique was effective in 98.5% of cases.²

A potential complication of RI is failure of the ETT to advance into the trachea after the guidewire and guide catheter are removed. Needle puncture at the cricotracheal ligament, just distal to the cricoid cartilage, increases the length of ETT in the larynx when the wire is removed, increasing the likelihood that advancing the tube into the trachea will be successful.¹¹ Feeding the guidewire through the Murphy eye, rather than the lumen, of the ETT, can achieve a similar effect.¹² A recent study performed on fresh cadavers evaluated the impact of a modified technique of RI to improve ETT guidance into the trachea.¹³