Anesthesia for pediatric airway endoscopy

Systematic Direct Laryngoscopy: The Lindholm Laryngoscopes

The authors, each with 40 years of experience in laryngology, aim to lay out the general principles and details of a systematic method of direct laryngoscopy for adults, children, and infants. Advances in laryngoscope design and application, advantages of telescopes, use of the operating microscope, and principles of modern anesthesia are highlighted. Particular reference is made to classification of laryngoscopes, advantages of Lindholm laryngoscopes, suspension laryngoscopy, the principles of biopsy, and problems of laryngoscopy. The difficult airway and the obstructed airway are discussed in detail. With the recent renewed interest in investigation and treatment of laryngeal problems and a better understanding of laryngeal physiology and voice production, the future will, no doubt, see new procedures to treat and restore laryngeal function. The fundamentals in this report form a basis for direct laryngoscopy, endolaryngeal microsurgery, laser surgery, and phonosurgery.

Challenging cases in pediatric anesthesia

Administering anesthesia to pediatric patients can always be challenging, especially for the nonpediatric anesthesiologist. Certain types of pathology and non-operating room settings can make these cases even more of a challenge, even for the most skilled pediatric anesthesiologist. This article will outline a few of these special situations, and attempt to give the practitioner an approach to the management of these patients.

Laryngeal Complications of Endotracheal Intubation

An endotracheal tube placed in the larynx, even for a short time, causes at least superficial mucosal damage, an injury that normally heals readily. Long-term intubation, on the other hand, may cause pressure necrosis that can extend into submucosa, perichondrium, and eventually cartilage. The sites of involvement include the medial surface of the arytenoid cartilages, vocal processes, cricoarytenoid joints, posterior glottis, and subglottis. We review the pathogenesis, endoscopic recognition, classification, and progression of intubation injuries and examine the many variables that influence them. Diagrammatic flow charts trace the acute injuries through to their chronic sequelae, including subglottic stenosis, which is commoner in infants and children, and posterior glottic stenosis, which is commoner in adults. Systematic endoscopic assessment, under general anesthesia, using rigid telescopes to evaluate laryngeal damage during intubation is recommended and critically discussed. Endoscopy permits an informed judgment with regard to continuation of intubation. Depending on the severity and depth of ulceration, intubation can be continued (sometimes with a tube of smaller diameter) or tracheotomy performed, with an awareness of the attendant risks and benefits. Unnecessary tracheotomies may be avoided. Further, it may be possible to minimize untoward outcomes of prolonged intubation by using management techniques directed at known risk factors.

Flexible fiberoptic bronchoscopy through the laryngeal mask airway in a small, premature neonate

The laryngeal mask airway (LMA) was introduced as a supraglottic device in anesthesia for routine use in the normal adult and pediatric population. Because the distal end of properly placed LMA faces the laryngeal inlet, this device can be used as a guide to flexible fiberoptic bronchoscopy (FFB) performance. In this clinical case, we present a small premature neonate with severe congenital biphasic stridor. FFB was performed successfully through the LMA while maintaining a patent airway during general anesthesia and permitting spontaneous respiration, as well as allowing assisted ventilation when necessary. An immediately subglottic intramural mass was revealed and tracheostomy was performed.

Canadian pediatric anesthesiologists prefer inhalational anesthesia to manage difficult airways: A survey

PURPOSE

To survey Canadian pediatric anesthesiologists to assess practice patterns in managing pediatric patients with difficult airways.

METHODS

Canadian pediatric anesthesiologists were invited to complete a web survey. Respondents selected their preferred anesthetic and airway management techniques in six clinical scenarios. The clinical scenarios involved airway management for cases where the difficulty was in visualizing the airway, sharing the airway and accessing a compromised airway.

RESULTS

General inhalational anesthesia with spontaneous respiration was the preferred technique for managing difficult intubation especially in infants (90%) and younger children (97%), however, iv anesthesia was chosen for the management of the shared airway in the older child (51%) where there was little concern regarding difficulty of intubation. Most respondents would initially attempt direct laryngoscopy for the two scenarios of anticipated difficult airway (73% and 98%). The laryngeal mask airway is commonly used to guide fibreoptic endoscopy. The potential for complete airway obstruction would encourage respondents to employ a rigid bronchoscope as an alternate technique (17% and 44%).

CONCLUSION

Inhalational anesthesia remains the preferred technique for management of the difficult pediatric airway amongst Canadian pediatric anesthesiologists. Intravenous techniques are relatively more commonly chosen in cases where there is a shared airway but little concern regarding difficulty of intubation. In cases of anticipated difficult intubation, direct laryngoscopy remains the technique of choice and fibreoptic laryngoscopy makes a good alternate technique. The use of the laryngeal mask airway was preferred to facilitate fibreoptic intubation.

Procedural sedation for children with special health care needs

Children with special health care needs represent a growing percentage of pediatric patients treated in all emergency departments. Substantial literature exists concerning the medical treatment of these patients, but there is little written describing the management of procedural sedation or analgesia in this population. This article examines the unique anatomic and physiologic implications of procedural sedation or analgesia management in children with special health care needs.

Use of intramuscular ketamine for endoscopy sedation in children

OBJECTIVE

To report the experience of the use of intramuscular (IM) ketamine for endoscopy sedation in children.

METHODOLOGY

Children over 6 months of age scheduled for elective endoscopy - esophagogastroduodenoscopy (EGD), bronchoscopy and nasopharyngolaryngoscopy (NPL) were enrolled for (2 mg/kg to 3 mg/kg) intramuscular ketamine sedation. A repeated dose of 2 mg/kg intramuscular ketamine was administered to those who failed the first sedation. Alternative sedation (intravenous midazolam and fentanyl) was given to children who failed ketamine sedation twice. Sedation was regarded as successful if the procedure was completed by endoscopist with a single dose of ketamine.

RESULTS

Sixty children were enrolled for the study. Overall success rate in our patients was 78.3%. Failure rate in infants was 50%, i.e. 4 out of 8. For children aged 1-7, the failure rate was 32%. Failure rate dropped markedly to 6.7% for those older than 7 years of age, and it showed significant difference when compared with the other two groups. Two cases of laryngospasm were experienced in the present study.

CONCLUSION

Intramuscular ketamine is an effective medication for sedation in endoscopy undertaken in children over age 7 years, but it should be avoided with children under age 7 because of the high failure rate.

Pediatric laryngoscopes: design and application

Examination of the upper aerodigestive tract for diagnosis and treatment has become more important in pediatric otolaryngology. Techniques of endoscopy have improved, anesthesia is safer, and there are many specialized laryngoscopes designed specifically for the small, sensitive airways of infants and children. Knowledge of the design advantages, specifications, and applications, including the use of telescopes and the operating microscope, will assist in selection of the appropriate laryngoscope for optimum exposure.

Pediatric otolaryngologic emergencies

Anesthesiologists are often consulted to help in the management of pediatric otolaryngologic emergencies. These include airway obstruction in children suffering from acute epiglottitis and croup. Surgical otolaryngologic emergencies such as foreign body aspiration, post-tonsillectomy bleeding, obstructive laryngeal papillomatosis, peritonsillar abscess, and laryngeal trauma can be life threatening. The pathophysiology, clinical course, and anesthetic management of these conditions are addressed with special emphasis on the details of airway management in each case.

Photography of severe laryngeal obstruction

Thirty-five-millimeter photography using rigid rod lens telescopes at direct laryngoscopy is the most versatile and reliable method of laryngeal documentation. Photography of severe laryngeal obstruction, whether in pediatric or adult patients, mandates a method of anesthesia chosen for maximum patient safety, a laryngoscope selected for optimal exposure, confidence in controlling the airway, and a technique that does not jeopardize the safety of the patient.