Point - Counterpoint
Counterpoint: Some Patients With Upper Respiratory Infection Will Require Endotracheal Intubation For Surgery
John Cross, MD
Staff Anesthesiologist
Co-Director, Pain Committee
Children's Hospital of Orange County
Orange, CA
Few events evoke more trepidation for the pediatric anesthesiologist than a failed airway. In planning the anesthetic for a child with an upper respiratory infection, sometimes the anesthesiologist, surgeon and parents will agree to try again another day. Other times we are riding into battle against an airway likely to cause problems, and maintaining the airway with an endotracheal tube may be our best defense. The risk of airway complications such as breath-holding, bronchospasm and laryngospasm when an endotracheal tube is used must be balanced against the risk of a failed airway without a tube in place.
For many surgeries, endotracheal intubation is desirable: surgery of the head, oropharynx and neck; major thoracic, abdominal and laparoscopic surgery; surgery in the lateral or prone position and surgery lasting more than 2 hours. For other cases, particularly the "bread and butter" variety found in outpatient surgery areas, a general anesthetic may be accomplished with a breathing circuit connected to a face mask or laryngeal mask airway (LMA). This technique usually uses spontaneous ventilation and avoids instrumentation of the airway and the negative effects of a tube in the trachea. Several conditions must be met to assure adequate management of the pediatric airway: oxygenation, ventilation, delivery of sufficient inhalation anesthesia and minimal gastric insufflation. Meeting these conditions is made more challenging by the presence of co-existing diseases that affect airway patency, pulmonary physiology and respiratory mechanics. Children with upper respiratory infections who also have such co-existing diseases are predisposed to poor oxygenation and ventilation when breathing spontaneously. These diseases include obesity, sleep apnea, facial and mandibular malformations, laryngomalacia, tracheomalacia, vocal cord polyps, a history of tracheoesophageal fistula repair or congenital diaphragmatic hernia repair, chronic lung disease, pulmonary hypertension, congenital heart disease, prune belly syndrome, cerebral palsy, muscular dystrophies and scoliosis. Muscular dystrophies require special consideration the Malignant Hyperthermia Association of the United States recommends that children with suspected Duchenne or Becker muscular dystrophy be given nontriggering anesthetics (1).
Rolf and Coté noted the increased incidence of minor desaturation events (SpO2 of 95% or less for 60 or more seconds) in the setting of upper respiratory infection (2). In children with co-existing diseases, spontaneous ventilation may be difficult to maintain without desaturating, and endotracheal intubation is indicated to facilitate positive pressure ventilation. A higher incidence of bronchospasm is expected but can be managed. With a face mask or LMA, the increased secretions of an upper respiratory infection pool in the oropharynx and predispose to coughing, aspiration and laryngospasm. Desaturation, hypoventilation and inadequate anesthetic depth may result if the patient is breathing spontaneously. Gentle assisted ventilation may be helpful, but if excessive positive pressure is required, the stomach will be insufflated, decreasing functional residual capacity and worsening oxygenation and ventilation. Endotracheal intubation is desirable in this setting. Tatari (3) and Tait (4) have shown a decreased incidence of respiratory complications with the LMA versus the endotracheal tube. However, these complications, such as breath-holding, laryngospasm, bronchospasm and oxygen desaturation to less than SpO2 90%, are manageable and transient. The LMA is irrefutably an
indispensable tool in our armamentarium for airway management. For a subset of children with upper respiratory infections, particularly those with co-existing diseases affecting the airway and pulmonary physiology, endotracheal intubation with positive pressure ventilation is the preferred technique for airway management.
References:
1. North American Malignant Hyperthermia Registry, ASA Newsletter, April 1997. http://www.asahq.org/NEWSLETTERS/1997/04_97/MH_Registry.html (Accessed July 25, 2002).
2. Rolf N, Cote CJ. Frequency and severity of desaturation events during general anesthesia in children with and without upper respiratory infections. J Clin Anesth 1992 May-Jun; 4(3):200-3.
3. Tartari S, Fratantonio R, Bomben R, Paolazzi M, Gritti G, Alvisi R. [Laryngeal mask vs tracheal tube in pediatric anesthesia in the presence of upper respiratory tract infection]. Minerva Anestesiol 2000 Jun;66(6):439-43. [Article in Italian]
4. Tait AR, Pandit UA, Voepel-Lewis T, Munro HM, Malviya S. Use of the laryngeal mask airway in children with upper respiratory tract infections: a comparison with endotracheal intubation. Anesth Analg 1998 Apr;86(4):706-11. #include ./footer_include.iphtml