Tsui, Ban C. H. MD, MSc, FRCP(C)*; Wagner, Alese BSc*; Cave, Dominic MB, FRCP(C)*; Elliott, Clark MD, FRCS†; El-Hakim, Hamdy MD, FRCS(Ed), FRCS(ORL)†; Malherbe, Stephan MB, ChB, FCA(SA), MMed(Anes)*
*Department of Anesthesiology and Pain Medicine and
†Department of Surgery, University of Alberta Hospitals, Edmonton, Canada
Supported, in part, by the Education and Research Fund, Department of Anesthesiology and Pain Medicine, University of Alberta Hospitals, Edmonton, Canada, and Clinical Investigatorship Award, Alberta Heritage Foundation for Medical Research, Alberta, Canada.
Accepted for publication September 8, 2003.
Address correspondence and reprint requests to Ban C.H. Tsui, MSC, MD, FRCP(C), Department of Anesthesiology and Pain Medicine, University of Alberta Hospitals, 3B2.32 Walter Mackenzie Health Science Centre, 8440-112 Street, Edmonton, Alberta, Canada T6G 2B7. Address e-mail to firstname.lastname@example.org.
In this case series, we evaluated the incidence of laryngospasm using a clearly defined awake tracheal extubation technique in 20 children undergoing elective tonsillectomy with or without adenoidectomy. This technique required patients to be turned to the recovery position at the end of the procedure before discontinuing the volatile anesthetics. No further stimulation, besides continuous oximetry monitoring, was allowed until the patients spontaneously woke up (“no touch” technique). The incidence of laryngospasm, oxygen saturation, and coughing was recorded. No cases of laryngospasm, oxygen desaturation, or severe coughing occurred in our patient population.
Preventing laryngospasm is an important consideration after adenotonsillectomy. Although studies have reported the incidence of laryngospasm after tonsillectomy and adenoidectomy to be as frequent as 21%–26%(1–4), this has not been the experience in our institution. Many of those studies have focused on pharmacological or invasive interventions, such as topical lidocaine, IV lidocaine, acupuncture, or IV magnesium to prevent laryngospasm, whereas little attention has been placed on the importance of extubation technique (1–4). This report describes a case series examining the incidence of laryngospasm using a properly defined awake (“no touch”) tracheal extubation technique after tonsillectomy with or without adenoidectomy.
After institutional ethics approval and written parental consent, 20 patients between the ages of 5 and 15 yr were enrolled in the study. All patients were ASA physical status I–III and underwent elective tonsillectomy with or without adenoidectomy. Patients with a history of asthma or predicted difficulty in tracheal intubation and extubation were excluded.
All patients received a standard general anesthetic with propofol 3–5 mg/kg and mivacurium 0.2–0.3 mg/kg to facilitate tracheal intubation. After the induction, morphine 0.15 mg/kg, ondansetron 0.15 mg/kg, and dexamethasone 0.2 mg/kg were administered. Anesthesia was maintained with 3%–5% desflurane in 50% nitrous oxide in oxygen. At the end of the procedure, blood and secretions in the pharynx were carefully suctioned, and the patients were then turned to the lateral (recovery) position while still adequately anesthetized. Desflurane and nitrous oxide were then discontinued while positive ventilation was continued with 100% oxygen until spontaneous ventilation returned. Absolutely no stimulation was allowed until patients spontaneously woke up. Tracheal extubation was performed when patients were able to open their eyes. An observer measured the time to tracheal extubation from discontinuation of the anesthetics, the occurrence of laryngospasm, the oxygen saturation (Spo2), and the severity of coughing at tracheal extubation. The severity of laryngospasm was graded on a four-point scale (3): 0 = no laryngospasm, 1 = stridor on inspiration, 2 = total occlusion of the vocal cords (silence with no air movement), or 3 = cyanosis. Coughing was evaluated using a modified four-point scale (5): 0 = none, 1 = slight, 2 = moderate, or 3 = severe.
A string swab with xylometazoline hydrochloride was frequently used to pack the nasopharynx at the end of the procedure. This pack was removed either before the termination of the anesthetics or at the time of tracheal extubation.
Using historical published control data listed in Table 2 for comparison, statistical analysis was performed with Fisher’s exact test. A P-level < 0.05 was considered statistically significant.
Laryngospasm did not occur in any of our 20 study patients. Table 1 summarizes the demographic data of our patient population. The median time to tracheal extubation was 7.7 min. Oxygen saturation levels never decreased to less than 92%, and no patients experienced severe coughing (Table 3).
One patient was excluded from our study because of violation of the “no touch” technique. This 15-yr-old patient was turned to the recovery position after the anesthetics had been terminated. This caused the patient to cough, dislodge the endotracheal tube, and develop laryngospasm that required immediate reintubation.
This is the first reported case series that examines the incidence of laryngospasm using a clearly defined awake “no touch” tracheal extubation technique after tonsillectomy with or without adenoidectomy. Using this tracheal extubation technique, no laryngospasm, severe coughing, or desaturation occurred in our patient population after extubation.
Laryngospasm is a serious complication after tracheal extubation under light anesthesia in pediatric patients. It has been suggested that the incidence of laryngospasm is reduced by either tracheally extubating patients in a deep plane of anesthesia or in a virtually conscious state (5). Leicht et al. (3), Lee et al. (2), and Koc et al. (1) used awake tracheal extubations for their studies but all reported a frequent incidence of laryngospasm (between 21% and 27%) in the control groups of posttonsillectomy patients. The aim of these three studies was to tracheally extubate all patients at the same depth of anesthesia using signs of swallowing as a clinical indicator for extubation. Consequently, their patients may have been extubated in a light plane of anesthesia because swallowing does not necessarily indicate consciousness but rather the return of laryngeal reflexes. We attempted to avoid extubation under light anesthesia by avoiding patient stimulation during emergence and performing extubations only when the patients opened their eyes. We had no cases of laryngospasm, severe coughing, or desaturation when tracheally extubating patients fully awake using our “no touch” technique.
A potential advantage of deep tracheal extubation, as opposed to awake extubation, is that patients are less likely to cough and strain afterward, thus avoiding the likelihood of laryngospasm and oxygen desaturation (6). Coughing and straining can also cause a previously dry tonsil or adenoid bed to hemorrhage. Although deep extubation might afford some protection against such responses, the risk of aspiration and inadequate airway protection during this vulnerable period remains a primary concern because there is evidence that the incidence of respiratory complications is more frequent when the trachea is extubated in a deep plane of anesthesia (5). In a recent study, Gulhas et al. (4) used deep tracheal extubation in posttonsillectomy patients and reported a frequent incidence of laryngospasm (25%) in the control group where magnesium was used in an attempt to decrease the incidence of laryngospasm. It is therefore desirable to develop a more effective extubation technique.
With the “no touch” technique, blood and secretions are carefully suctioned from the pharynx, and the patient is then turned to the lateral (recovery) position while adequately anesthetized. After being placed in the recovery position, the volatile anesthetics are discontinued, and no further stimulation is allowed until patients spontaneously wake up. This technique, combined with the rapid washout kinetic profile of desflurane, avoids stimulating and possibly arousing patients in a light plane of anesthesia. Adhering to this “no touch” protocol, we had no incidences of laryngospasm, desaturation, or excessive coughing, despite the use of a well-known airway irritant (desflurane). One case of laryngospasm occurred in an excluded patient when the “no touch” technique was violated. This patient was stimulated under light anesthesia after the anesthetics had been discontinued. This resulted in the patient developing laryngospasm, requiring re-intubation. This supports the importance of a “no touch” technique in preventing laryngospasm, although no conclusions can be drawn from a single case.
Caution is required when interpreting the clinical implications of these results. A deficiency of this case series is that there was no control extubation group with a deep or with a standard awake extubation group. Using historical published control data for comparison may leave our interpretations vulnerable to bias. However, the main objective of this report is to illustrate the shortcomings of a tracheal extubation technique in previously published data in this area. Despite the small sample size of this study, we still demonstrated a significant reduction in the incidence of laryngospasm compared with the before-mentioned studies (Table 2). This raises the question of the necessity of pharmacological intervention, such as with lidocaine or magnesium, to reduce laryngospasm after tonsillectomy and adenoidectomy. Most important, we propose that future studies in this area should use a clearly defined awake tracheal extubation technique when studying the effect of any pharmacological or nonpharmacological intervention in reducing the incidence of laryngospasm.
The authors would like to thank Dr R. Seal, Dr S. Clanachan, the Pediatric Recovery Room Nursing Staff, and Pediatric Anesthesiologists at the University of Alberta Hospital for their contribution.
1. Koç C, Kocaman F, Aygenç E, et al. The use of preoperative lidocaine to prevent stridor and laryngospasm after tonsillectomy and adenoidectomy. Otolaryngol Head Neck Surg 1998; 118: 880–2.
2. Lee CK, Chien TJ, Hsu JC, et al. The effect of acupuncture on the incidence of postextubation laryngospasm in children. Anaesthesia 1998; 53: 917–20.
3. Leicht P, Wisborg T, Chraemmer-Jørgensen B. Does intravenous lidocaine prevent laryngospasm after extubation in children? Anesth Analg 1985; 64: 1193–6.
4. Gulhas N, Durmus M, Demirbilek S, et al. The use of magnesium to prevent laryngospasm after tonsillectomy and adenoidectomy: a preliminary study. Paediatr Anaesth 2003; 13: 43–7.
5. Blair JM, Hill DA, Bali IM, Fee JPH. Tracheal intubating conditions after induction with sevoflurane 8% in children: a comparison of two intravenous techniques. Anaesthesia 2000; 55: 774–8.
6. Miller KA, Harkin CP, Bailey PL. Postoperative tracheal extubation. Anesth Analg 1995; 80: 149–72.