A major concern in caring for patients undergoing surgery while in the prone position is unintended tracheal extubation. This occurred during posterior cervical spinal fusion in a patient in whom airway management had been difficult. We follow the case presentation with a discussion of the factors contributing to the event.
The patient provided written permission for the authors to publish this report.
A 62-year-old kyphotic man presented with increasing upper extremity weakness and pain in his neck and C5-C7 discitis/osteomyelitis. The patient denied any additional medical conditions beyond obesity and severe cervical spine stenosis. He was brought to the operating room (OR) for an emergency C6-C7 corpectomy and anterior fusion. A cervical collar was in place, limiting his mouth opening and neck extension. He had a Mallampati 3 airway, had poor dentition, and an impressively large beard, which the patient wore for religious reasons. After a discussion involving both the patient and surgeon, in which we discussed the risks involved in potentially facing difficulty with mask ventilation, the patient maintained his desire to keep his beard.
Our plan for securing the patient’s airway started with an awake fiberoptic intubation, with a laryngeal mask airway (LMA) Supreme (LMA North America, San Diego, CA) readily available. Despite direct and rapid success passing a fiberoptic broncoscope (FOB) into his trachea, we were not able to pass the Medtronic Nerve Monitoring (NIM, Minneapolis, MN) endotracheal tube (ETT) past his glottis. At this point, we induced general anesthesia, with the goal of facilitating passage of the ETT. When this maneuver was unsuccessful, we experienced difficulty in ventilating the lungs via a mask, likely secondary to his long beard and airway anatomy. We then proceeded to direct laryngoscopy (DL) with inline stabilization. We were unable to visualize any part of his vocal cords (Cormack–Lehane grade 1V) and placed an LMA Supreme, which allowed ventilation of the lungs until a GlideScope (Verathon, Bothell, WA) was brought into the room. However, and unlike some other supraglottic airway devices, the LMA Supreme does not allow for intubation through its barrel, and tracheal intubation was then achieved by passing the large cuffed NIM ETT under indirect visualization using the GlideScope. The patient’s hemoglobin oxygen saturation (SpO2) remained 100% throughout this period. Tincture of benzoin was then applied to the patient’s face and beard, after which we taped the ETT in place.
The surgeon proceeded with the planned anterior C6-C7 corpectomy and fusion. He then decided to continue the case with a posterior fusion of C5-T2 as well, requiring a midcase prone repositioning. At this time, the ETT was resecured with extra tape to the patient’s face and forehead. Using Mayfield pinning (Integra, Plainsboro, NJ), the head was secured to the table, with the slack from the anesthesia circuit secured upward onto the table.
At completion of placement of the pedicle screws and just before attachment to the fusion plate, the surgeon requested radiographic examination of the spine to confirm screw placement. As the toroidal O-Arm machine (Medtronic, Minneapolis, MN) was positioned around the patient’s head, it came into contact with the ETT. Soon after, the ventilator bellows were noted not to be refilling after each breath. The ETT was visually checked, and, because there was no change in the capnogram at this time, the ETT was deemed to still be in place. However, because the pilot balloon was felt to be underinflated, several milliliters air was added, after which it was noted that the bellows were now completely collapsed, with the apnea alarm sounding 30 seconds later.
Additional anesthesia staff was called into the room. LMA placement was attempted with the patient still prone to no avail, and it was decided to turn the patient supine despite only the partial fusion and the open surgical field. The wound was covered with Ioban (3M, St. Paul, MN), a stretcher was obtained, and the patient placed supine.
The attending anesthesiologist attempted mask ventilation while the resident prepared an LMA and called for the GlideScope to be returned to the OR, because it had been removed for use in another location. As was the case on initial tracheal intubation, ventilation was extremely difficult and minimally effective. An LMA was placed, allowing minimal exchange of end-tidal carbon dioxide. DL was performed while waiting for the arrival of the GlideScope but was again unsuccessful. On its arrival, the GlideScope allowed placement of the ETT. The ETT was secured by wrapping tape eccentrically around the back of the patient’s head above his ears, because the surgical site precluded taping the posterior neck inferior to the ears. While the SpO2 decreased into the 60s for approximately 30 seconds, the patient had otherwise remained hemodynamically stable. Therefore, he was returned to the prone position, and the surgery was completed uneventfully.
Due to our concerns of airway edema from multiple instrumentations of the larynx and the surgeon’s concerns about surgically induced edema around the airway, the trachea remained intubated in the surgical intensive care unit but was extubated without incident the following morning.
No negative sequelae were evident from the brief period of desaturation (approximately 60–90 seconds). The patient was discharged home several days later. On follow up several months later, the patient was still doing well with no adverse effects from this event.
We feel that there were several contributing factors to the unplanned prone extubation. First, the patient’s beard not only made ventilation difficult, it also precluded taping the ETT to his facial skin. Some anesthesiologists suggest using the beard itself as part of the securement solution, by grooming the beard into sections, and then taping or tying the ETT with suture onto this more organized hair.1 Because our patient refused facial shaving, this technique may have been beneficial during this case.
Furthermore, secretions from the patients’ mouth interfered with the adhesive properties of the tape and the added weight of the NIM tube (with electrical cords for electromyographic monitoring) and heat and moisture exchanger while hanging below the patient likely contributed to the ETT gradually being pulled down. Finally, after noticing that there was a circuit leak and that the pilot balloon felt underinflated, additional air was injected into the ETT cuff and likely forced an already supraglottic ETT into the mouth. This resulted in the complete loss of ventilation occurring as the tip of the ETT moved above the vocal cords.
Emergency Airway Management of the Prone-Positioned Patient
While the traditional manner of airway management afthaner unintended tracheal extubation of the prone-positioned patient involves returning the patient to the supine position, this introduces some delay in a high acuity situation. The literature suggests that a return to the supine position may not be necessary as a first-line response due to the efficacy of LMA placement while the patient remains prone.2–9
Given the familiarity, availability, and ease of use of LMAs, many anesthesiologists are electing to use them in patients positioned prone. A review by Abrishami et al.2 of studies and case reports describing emergency LMA use in prone patients yielded a summary of 526 cases. The LMA was successfully inserted 87.5% of the time with first attempt improving to 100% success by the second attempt. However, in only 83% of cases was proper ventilation possible with the LMA. Additional case reports support this experience in neonatal, pediatric, and adult patients.3–5
The placement of LMAs in prone patients is not restricted to emergencies. Ng et al.6 reported a series of 73 patients in whom insertion of the LMA occurred after induction. Additionally as part of a retrospective audit, Brimacombe et al.7 reported the use of ProSeal LMAs in 245 patients. All attempts were successful, though 8 of 254 required a gum elastic bougie to aid in LMA placement during a second effort.
Hung et al.10 describe using a FOB to facilitate emergency intubation in the prone-positioned patient. Others have had success as well with FOB intubations in the prone patient.11–13 However, due to the additional time and equipment needed, an LMA would likely remain the most frequently used first choice. Also, once a supraglottic airway is successfully placed, it may be used as a conduit for a fiberoptic intubation, provided it is a device supporting such a maneuver. In our case, an intubating laryngeal airway, rather than an LMA Supreme, may have been a better choice to have readily available at the start of the procedure.
Some have used a traditional DL in the prone-positioned patient.14 Other reasonable options include video laryngoscopy. However, success in using any of these devices depends on the experience of the anesthesiologist as well as the availability of the equipment, and in the end, the best treatment is prevention of circumstances leading to tracheal extubation such as those occurring in our patient. Several methods of securing ETTs to patients before moving to the prone position have been proposed. These include using extra tape and dressings, commercial ETT holders, suturing the ETT to the cheek or around a tooth, or to a nasally routed pediatric orogastric tube.15–18
Remembering to tighten all circuit/tube connections can lesson the occurrence of disconnect, which could be confused for actual extubation. Some practitioners even prefer to tape all the circuit/tube connections together,15 though we do not recommend this as the tape may obscure a partial disconnect of the taped components. We also prefer using tape to secure the anesthesia circuit to either the OR table or the Mayfield frame to prevent the weight of the circuit from pulling on the ETT.
Failure of the original airway securement device or technique is a common cause of accidental extubation. Oral secretions and other fluids from the surgical fields can loosen the tape adhesive. Two techniques frequently used at our institution, and in this case, can help prevent this. First, after adequately securing the ETT with tape (usually >1 piece is required), an occlusive dressing is applied over the tape edges. We use Tegaderm (3M, St. Paul, MN) dressings in a variation of a technique originally described by Mikawa et al.16 Secretions have a much harder time, penetrating the Tegaderm to the tape itself.
In addition, before surgical preparation (if a cranial or cervical spine procedure), we often apply towels or small adhesive surgical drapes (1010; 3M, St. Paul, MN) on the sides of the head to prevent excess fluid from the surgical prep, or blood from the procedure, to track down the patient’s head, and directly onto our ETT. Of course, if the ETT is secured by means other than tape, these additional precautions are not needed. Finally while there are commercial tube holders available to assist in securing the tracheal tube, in a study by Carlson et al.,19 of 4 commercial tube holder devices, only 1 of 4 prevented extubation better than tape.
Difficult airways are by their very definition challenging encounters. An added degree of difficulty is found when tracheal extubation occurs in the prone-positioned patient. Our review of the literature suggests that physicians should incorporate the use of an LMA to their rescue efforts in the prone-positioned patient.
1. Khorasani A, Bird DJ. Facial hair and securing the endotracheal tube: a new method. Anesth Analg. 1996;83:886
2. Abrishami A, Zilberman P, Chung F. Brief review: Airway rescue with insertion of laryngeal mask airway devices with patients in the prone position. Can J Anaesth. 2010;57:1014–20
3. Taxak S, Gopinath A. Insertion of the i-gel airway in prone position. Minerva Anestesiol. 2010;76:381
4. Dingeman RS, Goumnerova LC, Goobie SM. The use of a laryngeal mask airway for emergent airway management in a prone child. Anesth Analg. 2005;100:670–1
5. Raphael J, Rosenthal-Ganon T, Gozal Y. Emergency airway management with a laryngeal mask airway in a patient placed in the prone position. J Clin Anesth. 2004;16:560–1
6. Ng A, Raitt DG, Smith G. Induction of anesthesia and insertion of a laryngeal mask airway in the prone position for minor surgery. Anesth Analg. 2002;94:1194–8
7. Brimacombe JR, Wenzel V, Keller C. The proseal laryngeal mask airway in prone patients: a retrospective audit of 245 patients. Anaesth Intensive Care. 2007;35:222–5
8. Agrawal S, Sharma JP, Jindal P, Sharma UC, Rajan M. Airway management in prone position with an intubating Laryngeal Mask Airway. J Clin Anesth. 2007;19:293–5
9. Osborn IP, Cohen J, Soper RJ, Roth LA. Laryngeal mask airway: a novel method of airway protection during ERCP: comparison with endotracheal tube. Gastrointest Endosc. 2002;56:122–8
10. Hung MH, Fan SZ, Lin CP, Hsu YC, Shih PY, Lee TS. Emergency airway management with fiberoptic intubation in the prone position with a fixed flexed neck. Anesth Analg. 2008;107:1704–6
11. Kramer DC, Lo JC, Gilad R, Jenkins A 3rd. Fiberoptic scope as a rescue device in an anesthetized patient in the prone position. Anesth Analg. 2007;105:890
12. Rampersaud YR, Moro ER, Neary MA, White K, Lewis SJ, Massicotte EM, Fehlings MG. Intraoperative adverse events and related postoperative complications in spine surgery: implications for enhancing patient safety founded on evidence-based protocols. Spine (Phila Pa 1976). 2006;31:1503–10
13. Neal MR, Groves J, Gell IR. Awake fibreoptic intubation in the semi-prone position following facial trauma. Anaesthesia. 1996;51:1053–4
14. van Zundert A, Kuczkowski KM, Tijssen F, Weber E. Direct laryngoscopy and endotracheal intubation in the prone position following traumatic thoracic spine injury. J Anesth. 2008;22:170–2
15. Ezike HA, Ajuzieogu VO, Amucheazi AO. A Reliable Method of Securing The Endotracheal Tube in Patients Undergoing Neurosurgical Procedure in the Prone Position. The Internet Journal of Anesthesiology. 2011;28
16. Mikawa K, Maekawa N, Goto R, Yaku H, Obara H. Transparent dressing is useful for the secure function of the endotracheal tube. Anesthesiology. 1991;75:1123–44
17. Ota Y, Karakida K, Aoki T, Yamazaki H, Arai I, Mori Y, Nakatogawa N, Suzuki T. A secure method of nasal endotracheal tube stabilization with suture and rubber tube. Tokai J Exp Clin Med. 2001;26:119–22
18. Bhat R, Ventkateshwaram GA. Secure method of nasotracheal tube fixation using the infant feeding tube. Anesth Analg. 2004;99:1352–4
19. Carlson J, Mayrose J, Krause R, Jehle D. Extubation force: tape versus endotracheal tube holders. Ann Emerg Med. 2007;50:686–91