Laryngeal Laser Surgery Research Articles

Office-Based 532-nm Pulsed KTP Laser Treatment of Glottal Papillomatosis and Dysplasia

Treatment of glottal papillomatosis and dysplasia was mirror-guided and done in surgeons' offices in the 19th century. It migrated to the operating room in the 20th century to accommodate direct laryngoscopic surgery, which required assistants to administer anesthesia and procedural support. The primary treatment goals, which are disease regression and voice restoration and/or maintenance, are tempered by the morbidity of general anesthesia and potential treatment-induced vocal deterioration. To obviate general anesthesia, office-based laser laryngeal surgery was first done in 2001 with the 585-nm pulsed dye laser (PDL), because it employs a fiber delivery system and its energy is selectively absorbed by oxyhemoglobin. Since then, this new angiolytic laser treatment paradigm has become a mainstay of management for many surgeons; however, there are a number of shortcomings of the PDL. To further develop this concept and address the limitations of the PDL, we used a 532-nm pulsed potassium titanyl phosphate (KTP) laser. A prospective assessment was performed on 48 patients in 72 cases of recurrent glottal dysplasia (36) or papillomatosis (36). All individuals had previously undergone microlaryngoscopic management with histopathologic evaluation. Two dysplasia patients did not tolerate the procedure. Of the treatable dysplasia cases, there was follow-up in 29 of 34. Disease regression was at least 75% in 18 of 29 cases (62%), 50% to 75% in 7 of 29 (24%), and 25% to 50% in the remaining 4 of 29 (14%). Papilloma patients returned for treatment when symptoms recurred, so disease regression could not be assessed accurately. Similar to data obtained with the PDL, these data confirmed that dysplastic mucosa could normalize without resection. Our observations revealed that the 532-nm pulsed KTP laser provided enhanced performance over the PDL laser in a number of ways. The ability to use smaller glass fibers precluded mechanical trauma to the channels of the flexible laryngoscopes and allowed for improved suctioning of secretions. Oxyhemoglobin absorbs energy better at 532 nm than at 585 nm, and the KTP laser can be delivered through a longer pulse width. These factors provide enhanced hemostasis and improved intralesional energy absorbance. Finally, unlike the PDL, the KTP laser is a solid-state laser and is not prone to mechanical failure.

Value of endotracheal tube safety in laryngeal laser surgery.

Due to the increased popularity of laryngeal laser therapy, surgeons and anesthesiologists are inevitably confronted with questions concerning the choice of the most efficient endotracheal tube (ETT) for laryngeal laser surgery, especially with regard to possible endolaryngeal tube fires, or combustions. The purpose of this study was to determine the current practice in endolaryngeal laser surgery in Germany. A questionnaire was sent to 152 ENT Departments in Germany, care was taken that the responders could send back the questionnaire anonymously. Among other questions the participants were asked for the number of lasersurgical treatments of the larynx performed in the past, the usual type of ETTs in use, whether other safety precautions were taken during CO2 laser surgery of the larynx and for intraoperative complications like tube ignition, fires or combustions. Eighty six of the 152 addressed ENT departments replied. In laryngeal laser surgery, 59/86 departments regularly use special laser tubes in daily routine (74.5%). In about 20,000 lasersurgical procedures, 15 incidents of ETT fire have been reported. In six of the reported 15 cases a tube fire occurred despite the fact that special laser tubes had been utilized. The present study could demonstrate that the use of special laser tubes does not necessarily protect against ETT fire. Thus, even when using special laser tubes other safety measures should be taken. In view of the maximum safety for the patient it has to be stated, that the safety during surgery correlates definitely with the experience of the surgeon. The weakest point of ETTs is usually situated in the cuff region.

Risk of Late Fatal Secondary Hemorrhage in Laser Surgery of the Larynx

Objectives: Since 1979, a number of publications have appeared regarding complications of laser surgery of the larynx. Most publications focus on complications such as accidental burns, rouse of the ventilation tube, anesthesiologic problems, edema of the mucosa, and abnormal scar formation. Secondary hemorrhage has played a subordinate role and cases demanding postoperative treatment have only been reported sporadically. All cases occurred within the first postoperative week, and no case resulting in death has been reported. The aim of the article is to draw attention to the fact that after laser surgery of the larynx, late lethal secondary hemorrhage may occur. Material and Patients: We review the literature and describe a patient in whom a lethal secondary hemorrhage occurred 10 days after laser supraglottic laryngectomy. The case is analyzed and similarities to hemorrhages associated with tonsillectomy and laser surgery of the lingual tonsil are shown. Results and Conclusions: The risk of very late severe secondary hemorrhage after laryngeal laser surgery is considered to be very seldom and comparable with that after tonsillectomy. Due to the increase in laser application in the treatment of laryngeal carcinoma, secondary hemorrhage may be encountered. Consequences for preoperative information and postoperative control of the patients have to be discussed.

Transtracheal high frequency jet ventilation for endoscopic airway surgery: a multicentre study

Serious complications during high frequency jet ventilation (HFJV) are rare and have been documented in animals and in case reports or short series of patients with a difficult airway. We report complications of transtracheal HFFJV in a prospective multicentre study of 643 patients having laryngoscopy or laryngeal laser surgery. A transtracheal catheter could not be inserted in two patients (0.3%). Subcutaneous emphysema (8.4%) was more frequent after multiple tracheal punctures. There were seven pneumothoraces (1%), two after laser damage to the injector, one after difficult laryngoscopy, four with no clear cause. Arterial desaturation of oxygen was more frequent during laser surgery and in overweight patients. Transtracheal ventilation from a ventilator with an automatic cut-off device is a reliable method for experienced users. Control of airway pressure does not prevent a low frequency of pneumothorax.

Airway ignition during CO2 laser laryngeal surgery and high frequency jet ventilation

Airway ignition during CO2 laser laryngeal surgery and high frequency jet ventilation

Anesthesia for Microlaryngeal Surgery: The Case for Subglottic Jet Ventilation

Although the techniques for surgery on the endolarynx using suspension and the operating microscope have been fully developed, the safest, and least obtrusive anesthetic technique has yet to be manifested, as evidenced by more than 200 references to anesthesia for microlaryngoscopy in the world literature. This study reviews the physiology, physics, and problems of each anesthetic technique. In light of this review, animal and human studies are reported demonstrating the utility and safety of subglottic ventilation when provided with proper monitoring using an automatic ventilator. A modified Ben-Jet tube is reported, which has a 1-mm ID channel to monitor PCO2 and tracheal pressure. This self-centering 3.0-mm tube, which extends 6 to 8 cm below the glottis, is unobtrusive for the surgeon. The subglottic tube, which is much less likely to be malaligned, is much more acceptable to the anesthesiologist. Anesthesia, by intravenous sedation, utilizes neuromuscular blockade while ventilating through the jet tube powered by an automatic ventilator with an automatic shutdown feature attached to the monitor tube to prevent inadvertent barotrauma. The third phase of this study compared fluoroplastic, used in a prototype jet ventilation tube, with 6-mm Silastic, Red Rubber, and polyvinyl chloride (PVC) tubes when struck by maximum power of CO2, Nd-YAG, and K-532 lasers. The test was performed in a closed chamber in which concentrations of oxygen and nitrogen were controlled. Although damaged by the CO2 laser beam, the fluoroplastic tubes did not continue burning when the laser was turned off in 100% oxygen, even when coated by blood. The other three tubes continued to burn in 23% oxygen. Neither the KTP nor Nd-YAG laser damaged the Teflon tube, while they ignited a sustained flame in 30% oxygen. This study supports the use of fluoroplastic for a laser safe jet ventilation tube. It also demonstrates the danger of tube fires, even in low oxygen concentrations, when using Silastic, rubber, and PVC tubes in laser laryngeal surgery. There was no difference in the flammability of Silastic, rubber or PVC when struck by these lasers in this study. For these reasons, subglottic ventilation using a fluoroplastic, monitored, self-centering, subglottic, jet ventilation tube driven by an automatic ventilator with a shutdown feature, in the event of excessive pressure buildup, is proposed for anesthetizing healthy patients undergoing suspension microlaryngoscopy, and who have no airway obstructing lesion. A large tube with inflatable cuff is indicated when a supraglottic lesion may obstruct the airway.

High frequency jet ventilation for microlaryngeal laser surgery. An improved technique.

The use of a triple lumen central venous catheter, which can be shielded from laser irradiation by metal tape, as a conduit for high frequency jet ventilation in six children, is described. The problems of anaesthesia for laryngeal laser surgery and the advantages of the technique described in this paper are discussed.

Tubeless translaryngeal superimposed jet ventilation

Microsurgical endoscopic interventions of the larynx offer an optimal approach to the surgeon by providing an unrestricted operative field. During such operations, ventilating the patient should in no way be impaired. For this reason we have developed a new type of tubeless jet ventilation which consists of both low-frequency and superimposed high-frequency jet ventilation. In addition, we have integrated two specifically sized jets into a Kleinsasser laryngoscope, placing them at different sites. This technique guarantees adequate ventilation with an oxygen-air blend. Due to the Venturi effect, air and tidal volumes are also enhanced when passing through the external open end of the laryngoscope. This type of tubeless jet ventilation was applied to more than 60 patients, using a prototype jet. Anesthesia consisted of a continuous intravenous administration of propofol, with sufentanil and vecuronium given as needed. Clinical results revealed optimal ventilation of all patients without hypercapnia or other complications. Operative conditions for the surgeon were also very satisfactory. Findings demonstrated that this type of tubeless jet ventilation is also particularly suited for laryngeal laser surgery, thus avoiding flammable tubes and noxious anesthetics.

Laser resistant stainless steel endotracheal tube: Experimental and clinical evaluation

A fire due to endotracheal tube (ET) ignition is a catastrophic event that may occur during laser surgery of the upper airway, regardless of the wavelength utilized. Although methods exist that permit laser surgery without an ET, this is frequently not feasible. The current investigation was undertaken to evaluate the efficacy of a double-cuffed stainless steel ET, first in the laboratory and subsequently in a clinical setting. Bench testing was performed using CO2 (both standard and milliwatt) and KTP/532 lasers. Only the distal polyvinyl chloride cuffed end of the tube was potentially ignitable, however, the appropriate use of saline to fill the cuffs allowed only for cuff perforation without ignition. Canine testing was performed in 10 animals: 4 dogs were intubated from 3 to 4.5 hours with the laser resistant stainless steel endotracheal tube (LRSS-ET) (Laser-Flex Tracheal Tube; Mallinckrodt Anesthesia Products, St. Louis, MO) and 2 with an aluminum tape wrapped red rubber ET. Visual and histological examination were performed in both groups at 3 and 7 days. Four dogs underwent CO2 laser laryngeal surgery with visual and histological examination performed at 7 days postoperatively. No untoward effects could be demonstrated due to the LRSS-ET. A clinical study was then performed in 24 patients who underwent laser surgery of the upper aerodigestive tract with either a CO2 or KTP/532 laser. In all cases ventilation was adequate, the shaft of the LRSS-ET proved impervious to the laser, and the distal end of the tube protected the tracheobronchial tree safely.(ABSTRACT TRUNCATED AT 250 WORDS)

Avoiding a wrapped endotracheal tube in laser laryngeal surgery: Experiences with apneic anesthesia and metal laser‐flex endotracheal tubes

Ninety-one laser laryngeal procedures using the apneic technique of anesthesia were performed in 28 patients between 2 months and 64 years of age. Seventy-two procedures (79%) were performed on children and 19 on adults. There were no complications. Eight laser laryngoscopies were performed using a new metal Laser-Flex endotracheal tube. Obstruction of the endotracheal tube with a mucous plug occurred in one case. The apneic technique described in this paper provides a laser operative field free of an endotracheal tube, virtually eliminating the danger of a laser fire. It is a relatively safe and effective means of performing laser laryngeal surgery. In addition, the Laser-Flex endotracheal tube appears to be an acceptable alternative to a metallic tape-wrapped endotracheal tube.

Sonographie des Kehlkopfes im Kindesalter. Neue Perspektiven durch Einsatz der Computersonographie - Teil 2: Der sonographische Befund einer Larynxpapillomatose

On our opinion one important indication for sonographic diagnosis in future are masses in the larynx area: in infancy or childhood mainly laryngeal papillomatosis. In one of our boy patients with massive laryngeal papillomatosis laser surgery was first performed at 15 months of age. After a second and third procedure interferon-therapy was begun. Sonographically it was easily possible to follow the course in control examinations. Sonographic findings correlated well with laryngoscopic findings. Laryngoscopy could therefore be limited to a minimum.

Ventilation par sonde métallique pour la chirurgie laryngée au laser CO 2

One of the risks of laryngeal laser surgery is the ignition of the disposable plastic endotracheal tubes used for ventilation. In 1985, Hunton and Oswal ( Anaesthesia, 40 : 1210, 1985) developed a metallic tube which is now available in France. In this study, the tube has been tested on 30 patients undergoing this type of surgery. The tube was sterilized in glutaraldchyde before re-using it. There never was any problem with placing the tube and surgical conditions were satisfactory. There was neither incident due to the laser, nor any difficulties with the use of high-frequency jet-ventilation. The blood gas values were satisfactory (mean Pa o 2 : 19.4 ± 4.2 kPa ; mean Pa co 2 5.0 ± 0.46 kPa). After a use in 30 consecutive patients, the tube was not damaged. The advantages and disadvantages of this tube are discussed, considering the other types of special laser surgery endotracheal tubes. This metallic tube is not flammable, can be used several times, occupies only a small space and does not hurt tissues. Moreover, it is cheaper than disposable tubes when the price is calculated per patient. It would therefore seem that Hunton and Oswal's metallic tube, used with high-frequency jet-ventilation is a good alternative for tubes used today.

Anaesthesia for carbon dioxide laser laryngeal surgery in infants

Summary Problems associated with the presence of a tracheal tube during anaesthesia for infant laryngeal surgery using the carbon dioxide laser are described. This paper discusses alternatives and describes an effective anaesthetic technique and a new tracheal tube.

Anaesthesia for carbon dioxide laser laryngeal surgery in infants. A new tracheal tube.

Problems associated with the presence of a tracheal tube during anaesthesia for infant laryngeal surgery using the carbon dioxide laser are described. This paper discusses alternatives and describes an effective anaesthetic technique and a new tracheal tube.

Jet ventilation for laser laryngeal surgery in children. Modification of the saunders jet ventilation technique

In our clinical series, 40–50% O 2 and 50–60% N 2O (regulated by a blender and delivered by manual jet ventilation (MJV)) and residual halothane from induction provided satisfactory supralaryngeal anesthesia. Fentanyl, N 2O, atracurium, and lidocaine administered i.v. effectively blunted laryngeal stimulation, allowed control of respiration, and minimized vocal cord motion. Wide unobstructed surgical access to the entire endolarynx is provided. Atracurium (an intermediate-acting non-depolarizing muscle relaxant administered in a single bolus or by constant infusion) achieves the needed level of blockade and permits the anesthesiologist to focus on the pattern of respiration rather than the degree of neuromuscular blockade. Its duration of action seems to be well matched to the average duration of this surgical procedure. Because its reversal is prompt (35–45 min from i.v. injection to 25% recovery by neuromuscular transmission monitor) (Brandom et al, Clinical pharmacology of atracurium in paediatric patients, Br. J. Anaesth., 55 (1983) 117S–121S) children can be discharged safely from the recovery room to home after an appropriate period of observation in the short-stay unit. Our report confirms and extends another recent report supporting supraglottic jet ventilation (Scamman, F.L. and McCabe, B.F., Supraglottic jet ventilation for laser surgery of the larynx in children, Ann. Otol. Rhinol. Laryngol., 95(1986) 142–145). We belive that the MJV techinique is advantageous in children, particularly for outpatient surgery. Attention to detail and careful communication between a skilled anesthesilogist and surgeon are essential. Dangerous barotrauma can occur and skill and monitoring are essential.

Endotracheal tube safety during laser surgery

The most morbid complication of laryngeal laser surgery is an endotracheal tube fire. The purposes of this study were to determine the efficiency of saline solution-soaked cottonoid pledgets in protecting endotracheal tube cuffs from the laser beam and to evaluate the safety of four commonly used endotracheal tubes. The method involved measurement of perforation times of saline-soaked cottonoid pledgets with controlled variables of air exposure times and laser energy. The second part evaluated the safety and ignition properties of the red rubber, silicone, polyvinyl chloride, and Xomed Laser-Shield tubes by studying their perforation times and ignition properties under controlled oxygen concentrations. The results revealed that saline-soaked pledgets are very efficient in protecting endotracheal tube cuffs. The Laser-Shield tube was the safest one studied. It had the highest ignition threshold of the four tubes tested.

Proximal large-bore jet ventilation for laryngeal laser surgery.

The carbon dioxide surgical laser has made many open upper airway operations obsolete. However, new laser-related hazards have been encountered, the most serious of which is fire in the airway. Venturi jet ventilation removes that risk and provides an unobstructed surgical field. Indications and techniques for the use of jet ventilation with carbon dioxide laser surgery remain controversial, particularly whether jet ventilation should be used in papillomatosis or in the severely obstructed airway, and whether proximal and distal catheter techniques are equally safe and effective. We report the successful use of proximal large-bore Venturi jet ventilation in 327 consecutive patients undergoing microlaryngeal laser surgery. The technique is ideal for pediatric patients with subglottic stenosis or recurrent respiratory papillomas and has not caused distal seeding in the latter group. We recommend the use of low-pressure ventilation, even in relatively obstructed airways. The experimental evidence reported here corroborates the clinical viewpoint expressed; the technique is safe, simple, and uncomplicated if used with care.

Safe anesthesia for endoscopic laryngeal laser surgery.

Anesthesia safety for endoscopic laryngeal laser surgery has been a major limiting factor for laser applications in the larynx and the hypopharynx. Several anesthesia techniques have been proposed and each technique appears to have its own limitations. This paper will deal with the distinct advantages offered by the malleable copper tube which is used for delivery of the open Venturi system anesthesia for endoscopic laser surgery. A retrospective study of 100 patients who have undergone this modality of anesthesia at our institution will be presented. Our conclusion from this study shows clearly the superiority of the copper tube over the conventional aluminium-foil-wrapped endotracheal tube in safety and the exposure of the larynx during surgery.

Jet insufflation anesthesia for endolaryngeal laser surgery: A review of 318 consecutive cases

A series of 318 patients utilizing the jet insufflation technique for laser laryngeal anesthesia was studied. The technique utilizes a foil wrapped catheter placed below the vocal cords and attached to the Sanders ventilating adapter. Two pneumothoraces in children, one dental injury and one tube ignition were noted--all without permanent sequelae. Subsequent modification in technique prevented recurrence of these complications. The results indicate that this is a safe technique for laryngeal laser surgery, providing excellent visualization of the larynx while maintaining good oxygenation and airway control.

Anesthesia for Laryngeal Laser Surgery in the Infant and Child

Anesthesia for Laryngeal Laser Surgery in the Infant and Child