High frequency jet ventilation via a tracheoscope for endobronchial laser surgery

High-Frequency Jet Ventilation in Nonintubated Patients

OBJECTIVES

High-frequency jet ventilation (HFJV) is a convenient method for providing ventilation during fiberoptic bronchoscopy. We describe an incipient approach of high-frequency jet ventilation via the working channel of a flexible bronchoscope for nonintubated patients who suffer from hypoxemia during bronchoscopy. The aim of this study was to test the efficacy of this incipient approach and determine the possible complications related to it.

MATERIALS AND METHODS

Sixteen patients who had oxygen saturation below 70% that did not resolve with nasal oxygen for 20 s during interventional bronchoscopy were included in the study. High-frequency jet ventilation was administrated via the working channel of a bronchoscope for 3 min. Arterial blood gas circumscriptions were compared before and after jet ventilation.

RESULTS

Oxygen saturation increased to >90% in all patients 30 s after jet ventilation. Mean arterial oxygen saturation pressure increased from 54.84 to 111.98 mmHg with jet ventilation (p=0.0001). Arterial carbon dioxide tension decreased after jet ventilation. The body mass index had no consequential effect on arterial carbon dioxide pressure after jet ventilation in our patients (p=0.1). Complications such as pneumothorax and working channel damage were not observed.

CONCLUSION

High-frequency jet ventilation via the working channel of the bronchoscope is a novel method that can provide optimal ventilation with minimal complications to nonintubated patients suffering from hypoxemia during bronchoscopy. This method also reduces the duration of bronchoscopy procedures.

High-frequency jet ventilation in interventional bronchoscopy: factors with predictive value on high-frequency jet ventilation complications

STUDY OBJECTIVE

To evaluate the incidence and impact on clinical outcome of complications observed during high-frequency jet ventilation (HFJV) at interventional bronchoscopy and to identify the perioperative factors that may be associated to an increased incidence of such complications.

DESIGN

Observational retrospective, study with an observational prospective validation of the statistically significant associations.

SETTING

University hospital.

PATIENTS

The retrospective study involved 276 patients who underwent an interventional rigid bronchoscopy during general anesthesia and HFJV. Forty consecutive patients were accrued for the prospective validation group. INTERVENTIONS/MEASUREMENTS: Information recorded included patient medical history and perioperative complications observed at HFJV-managed bronchoscopic procedures and their impact on clinical outcome until hospital discharge.

MAIN RESULTS

At least one complication was detected in 38% of retrospective patients and 55% of prospective patients. Most frequent complications were hypercapnia, hypoxemia, and hemodynamic instability, but just one case of barotrauma in the retrospective group. Despite the high incidence, these complications were transient and did not increase hospital stay, whereas technical failure to widen airway lumen was associated with an adverse prognosis. Several clinical parameters showed a significant association with complications in the univariate analysis. However, the multivariate analysis only evidenced two independent predictive factors: the ASA physical status scale and baseline oxygen saturation.

CONCLUSIONS

Classification in ASA physical status IV group and a baseline oxygen saturation of 95% or less independently predicted the development of complications during interventional rigid bronchoscopy with HFJV.

Anesthetic management of laser surgery for central airway obstruction: a 12-year case series

The retrospective 12-year experience of anesthetizing patients with central airway obstructions for laser treatment with a CO2 and two types of Nd:YAG laser has been reviewed and evaluated. More than 300 patients have been treated, many on several occasions. The beneficial effects of treatment to the majority of patients have been significant. There has been a small associated mortality because the majority are in the high-risk categories of fitness for anesthesia, but no clinical evidence that it is directly attributable to the techniques of anesthesia or ventilation. Therefore, although laser technology has evolved into systems suitable to be applied with fiberoptic bronchoscopes and local and sedation anesthesia, the use of a rigid bronchoscope and the evolved techniques of anesthesia and ventilation remain appropriate to the clinical needs and offer advantages.

High-frequency jet ventilation--a review of its role in laryngology

High-frequency jet ventilation (HFJV) is a safe, effective anaesthetic technique with a low risk of aspiration which has not yet gained wide acceptance in laryngology. Following anaesthesia and muscular relaxation the patient is intubated with a size 7FG infant feeding catheter and ventilation is achieved by delivering small bursts of anaesthetic gas at high frequency. The mechanisms of gas exchange are thought to be little different from those of conventional ventilation. We have found HFJV to be of value in laryngoscopy, laryngo-tracheal reconstruction, tracheoplasty, bronchoscopy and tonsillectomy. The advantages include: (a) ease of intubation, especially in the presence of a supraglottic mass; (b) improved surgical access compared with a conventional endotracheal tube; and (c) protection of the airway by the inherent 'auto-PEEP' effect. Care must be taken to ensure that conditions allow adequate exhaust of expired gas. Humidification of inspired gas is essential during prolonged procedures.

Tracheoscope: an old instrument with new applications

The tracheoscope is a bronchoscope without the side ventilating ports at the distal tip. It has been used for decades, implementing diagnostic and therapeutic procedures in the subglottis and cervical and thoracic trachea. The closed tube tracheoscope allows excellent control of the airway with maintenance of continuous anesthesia and ventilation. Flexible fiber-directed lasers, such as the potassium-titanyl phosphate laser, can be used with the tracheoscope for laser resection or vaporization of diseased tissue from just below the vocal cords to any level within the trachea. Controlled anesthesia and smoke evacuation are maintained throughout the operation, allowing a relatively safe endoscopic procedure. Disorders such as subglottic hemangioma, subglottic or tracheal webs, papillomatosis, granuloma, and a variety of neoplastic growths can be excised, debulked, or submitted to biopsy by means of this instrument. In the neonatal and infant airway, use of the tracheoscope concomitantly with rigid telescopes has been particularly rewarding.