Endotracheal tube obstruction: a rare complication in laser ablation of recurrent laryngeal papillomas. (Original Article).

Abstract

During the past 25 years, use of the carbon dioxide (CC2) laser has been accepted as the most appropriate surgical method for the treatment of recurrent laryngeal papillomatosis. Although [CO.sub.2] laser technology and surgical techniques continue to improve, laser-related complications still occur. We describe a case of a very rare complication--to our knowledge, only the second such case reported in the literature--in which an endotracheal tube was almost completely obstructed by a piece of papillomatous tissue during [CO.sub.2] laser microlaryngoscopy for the treatment of recurrent laryngeal papillomatosis.

Introduction

Recurrent laryngeal papillomatosis is a disease of viral etiology that occurs in both juvenile- and adult-onset forms. Lindeberg et al classified this disease into four clinical categories: juvenile single, juvenile multiple, adult single, and adult multiple. (1)

Over the past 2 decades, a variety of treatments has been proposed for the management of recurrent laryngeal papillomatosis, including surgical excision, (2) cryosurgery, (3) steroids, (4) podophyllum, (5) interferon, (6) and laser surgery. (7) None of these modalities can totally eradicate the disease, but the carbon dioxide ([CO.sub.2]) laser appears to be the most accepted method of treatment because of its ability to vaporize papillomas without causing bleeding or edema and for the precise way in which it removes lesions without causing injury to underlying laryngeal structures. Even so, complications still occur.

In this article, we describe what we believe is only the second reported case of endotracheal tube obstruction caused by an avulsed papilloma during intubation in [CO.sub.2] laser surgery for the management of recurrent laryngeal papillomatosis.

Case report

A 4-year-old white girl was admitted for removal of recurrent papillomas of the larynx. The patient had undergone three previous [CO.sub.2] laser excisions. Evaluation in the clinic the day before surgery revealed that the child had a 3-week history of increasing hoarseness and increasing stridor while sleeping at night. Flexible endoscopy in the office had detected a large papillomatous mass in the left larynx. Findings on the remainder of the physical examination were unremarkable.

The patient was brought to the operating room and given mask sedation. After an intravenous peripheral catheter was placed, the patient was intubated with a 3.0-mm internal-diameter (ID) flexible metal laser endotracheal tube. At this point, the anesthesia personnel reported some mild difficulty in ventilating the patient. The difficulty appeared to resolve with albuterol treatment, and the patient retained her oxygen saturation level in the range of 99 to 100%. We proceeded with the surgery, and the patient was allowed to breathe spontaneously during the procedure.

A Dedo anterior commissure laryngoscope was introduced into the patient's oral cavity and advanced into the larynx under direct visualization. A large laryngeal papilloma that had originated in the left false vocal fold was noted. The lesion appeared to extend into the ventricle.

The papilloma on the left false vocal fold was ablated with continuous [CO.sub.2] laser energy at 5W. On examination of the right side of the larynx, a small area of papilloma on the right true vocal fold was noted. At this point, a small amount of papillomatous tissue was observed in the distal opening of the endotracheal tube; it had been inserted at the beginning of the operation, possibly when the patient was intubated. The laryngoscope was removed, and preparation for anesthesia reversal was initiated. Upon removal of the endotracheal tube, the patient exhibited no respiratory problems. However, we noted that a plug of papillo matous tissue had almost completely occluded the distal tip of the endotracheal tube (figure). With the use of flexible bronchoscopy, we noted no distal dislodgment of tissue in the tracheobronchial tree. Following the bronchoscopy, the patient was awakened from the general anesthesia, and she recovered uneventfully. Apparently, because the endotracheal tube was small, the patient was able to ventilate around it because she was allowed to breathe spontaneously during surgery.

Discussion

Extensive information regarding the use of the [CO.SUB.2] laser in recurrent laryngeal papillomatosis has been accumulated since it was first used in the 1970s. (7) This experience includes the reporting of various immediate and long-term complications.

Reported complication rates. In a study of all types of [CO.SUB.2] laser surgery in the upper aerodigestive tract, Healy et al reported a complication rate of 0.2% (nine complications in 4,416 procedures). (8) Six of these nine complications were life-threatening; five involved a fire in the endotracheal tube and one involved the ignition of a dry sponge that was placed over a tracheostomy in a pediatric patient during laser bronchoscopy for papillomatosis of the tracheobronchial tree. The other three complications were minor: two cases of hemorrhage and one case of skin burn.

Ossoff et al reported a complication rate of 5.9% (12 complications among 204 procedures); none was lifethreatening. (9) Theirreview demonstrated the relative safety of the CO laser when it is used judiciously, and they 2 recommended the Rusch red rubber endotracheal tube wrapped with reflective metallic tape as the safest of these instruments.

Wetmore et al reviewed 222 cases of [CO.sub.2] laser surgery for recurrent laryngeal papillomatosis and reported a laser-related complication rate of 0.5%. (10) In their study, no airway fire was reported, and the only life-threatening complication was a case of bilateral pneumothorax.

Types of complications. The complications of [CO.SUB.2] laser microlaryngoscopy can be classified as direct, secondary, or delayed (table):

Direct complications. Direct laser complications are caused by direct contact of the laser beam with objects in the operative field. The extent of resultant tissue damage is related with the basic parameters of the [CO.SUB.2] laser, such as the duration of exposure and the power density absorbed by the tissue. Direct complications include the most serious [CO.SUB.2] laser complication: endotracheal tube ignition. (8, 11) Most cases of endotracheal tube fire occurred during the early years of [CO.SUB.2] laser microlaryngoscopy when a laser beam made contact with the external surface of an unprotected endotracheal tube or a tube that was poorly wrapped with aluminum tape. Another major direct complication is tracheal perforation, which can lead to pneumothorax and subcutaneous emphysema. (10)

Secondary complications. Secondary laser complications are indirectly related to the laser beam's impact on tissue. Major secondary complications include endotracheal tube ignition by flaming ablated tissue and tube obstruction by ablated tissue. Other secondary complications include airway obstruction from displaced aluminum foil, (12) mucosal charring, hemorrhage, edema, and perichondritis.

Delayed complications. Delayed laser complications occur after the healing process has been completed. They include vocal fold webs, (10) laryngeal and tracheal cicatrix, glottic incompetence as a result of excessive tissue removal, (13) laryngeal carbon granuloma, (13) and papilloma implantation elsewhere in the upper aerodigestive tract. (14) Ossoff et al postulated that most delayed complications are related to excessive ablation of tissue and the transmission of thermal energy into the underlying lamina propria. (9)

To our knowledge, the only other case of such an endotracheal tube obstruction by ablated tissue was reported in 1980 by Torres and Reynolds. (15) Their case involved a 4.0-mm ID tube. Our patient was able to ventilate around the small, cuffless 3.0-mm ID tube because she was allowed to breathe spontaneously during surgery. If tube obstruction by papillomatous tissue is suspected, the tube should be removed and intraoperative bronchoscopy should be performed.

We conclude by emphasizing the necessity of surgeons being completely familiar with their laser equipment and the importance of safety protocols.

able

Three types of complications of [CO.sub.2] laser microlaryngoscopy for
recurrent laryngeal papillomatosis


Direct complications
Endotracheal tube ignition
Ignition of cottonoid
Tracheal perforation
Pneumothorax
Subcutaneous emphysema
Mucosal burn
Corneal burn
Cuff rupture

Secondary complications
Endotracheal tube ignition from insufflated lasered tissue
Endotracheal tube obstruction by lasered tissue
Airway obstruction from displaced aluminum foil
Mucosal charring
Hemorrhage
Edema
Perichondritis

Delayed complications
Acquired vocal fold webs
Laryngeal or tracheal cicatrix
Glottic incompetence caused by excessive tissue removal
Laryngeal carbon granuloma
Papilloma implantation elsewhere in the upper
 aerodigestive tract

References

(1.) Lindeberg H, Oster S, Oxlund I, Elbrond O. Laryngeal papillomas: Classification and course. Clin Otolaryngol 1986;11:423-9.

(2.) Holinger PH, Schild JA, Maurizi DG. Laryngeal papilloma: A review of etiology and therapy. Laryngoscope 1968;78:1462-74.

(3.) Singleton GT, Adkins WY. Cryosurgical treatment of juvenile laryngeal papillomatosis. An eight year experience. Ann Otol Rhinol Laryngol 1972;81:784-90.

(4.) Szpunar J. Laryngeal papillomatosis. Acta Otolaryngol 1967;63:74-86.

(5.) Dedo HH, Jackler RK. Laryngeal papilloma: Results of treatment with the CO2 laser and podophyllum. Ann Otol Rhinol Laryngol 1982;91:425-30.

(6.) Haglund S, Lundquist PG, Cantell K, Strander H. Interferon therapy in juvenile laryngeal papillomatosis. Arch Otolaryngol 1981;107:327-32.

(7.) Strong MS, Vaughan CW, Cooperband SR, et al. Recurrent respiratory papillomatosis: Management with the CO2 laser. Ann Otol Rhinol Laryngol 1976;85(Pt l):508-16.

(8.) Healy GB, Strong MS, Shapshay S, et al. Complications of CO2 laser surgery of the aerodigestive tract: Experience of 4416 cases. Otolaryngol Head Neck Surg 1984;92:13-18.

(9.) Ossoff RH, Hotaling AJ, Karlan MS, Sisson GA. C02 laser in otolaryngology-head and neck surgery: A retrospective analysis of complications. Laryngoscope 1983;93:1287-9.

(10.) Wetmore SJ, Key JM, Suen JY. Complications of laser surgery for laryngeal papillomatosis. Laryngoscope 1985;95(Pt l):798-801.

(11.) Leibowitz HM, Peacock GR. Corneal injury produced by carbon dioxide laser radiation. Arch Ophthalmol 1969;81:713-21.

(12.) Cozine K, Stone JG, Shulman S, Flaster ER. Ventilatory complication of carbon dioxide laser laryngeal surgery. J Clin Anesth 1991;3:20-5.

(13.) Feder RJ. Laryngeal granuloma as a complication of the CO2 laser. Laryngoscope 1983;93:944-5.

(14.) Meyers A. Complications of CO2 laser surgery of the larynx. Ann Otol Rhinol Laryngol 1981;90(Pt 1):132-4.

(15.) Torres LE, Reynolds RC. A complication of use of a microlaryngeal surgery endotracheal tube [letter]. Anesthesiology 1980;53:355.

From the Department of Otolaryngology-Head and Neck Surgery, University of Virginia Medical School, Charlottesville.

Reprint requests: Stilianos E. Kountakis, MD, PhD, Professor and Vice-Chair, Department of Otolaryngology-Head and Neck Surgery, Medical College of Georgia, 1120 Fifteenth St., Augusta, GA30912-4060. Phone: [phone]; fax: [phone]; email: skountakis @mcg.edu