Incidence of pulmonary edema after tracheotomy for obstructive sleep apnea.

OBJECTIVE: The phenomenon of postobstructive pulmonary edema (POPE) has been associated with the relief of upper airway obstruction, which itself is fundamental to the pathophysiology of obstructive sleep apnea (OSA). A review of patients with OSA undergoing tracheotomy was performed to characterize this process. STUDY DESIGN: Retrospective chart review of study patients with OSA undergoing tracheotomy and of control patients without OSA undergoing tracheotomy for unrelated problems. Chest radiographs were reviewed in a double-blind fashion to score posttracheotomy changes in pulmonary status. SETTING: Academic tertiary referral center. RESULTS: Thirty (67%) of 45 OSA patients treated by tracheotomy had evidence of POPE, whereas only 5 (20%) of 25 control group patients had increased pulmonary edema. The remaining 15 (33%) of 45 OSA patients and 20 (80%) of 25 control patients had either no change or an improved pulmonary status. Those with OSA that developed POPE were mostly graded as having mild pulmonary edema (22/30, 73%). Far fewer were graded as having moderate pulmonary edema (6/30, 20%), and fewer still with severe pulmonary edema (2/30, 7%). Two (7%) of 45 patients with severe POPE died of complications related to cor pulmonale in the postoperative period. CONCLUSION: Results support maintaining a high index of suspicion for the development of postobstructive pulmonary edema in patients treated for OSA. Treatment options, such as positive pressure ventilation and diuresis, and an increased awareness of this condition may help reduce the morbidity and mortality associated with treatment of this disease.

Laryngospasm and diaphragmatic arrest in immature dogs after laryngeal acid exposure: a possible model for sudden infant death syndrome.

Laryngopharyngeal reflux has been proposed as a possible cause of sudden infant death syndrome (SIDS). We investigated the efferent laryngeal and diaphragmatic responses to acid exposure on the laryngeal mucosa using a neonatal canine model. Electromyographic (EMG) recordings from the thyroarytenoid muscle and the diaphragm were measured with hooked-wire electrodes. Reproducible laryngospasm responses occurred in all animals after laryngeal exposure to hydrochloric acid at pH 2.0 or less. Laryngospasm occurred in combination with tachypnea and increased diaphragmatic activity in most of the animals. Laryngospasm was associated with prolonged apnea and total cessation of diaphragmatic EMG activity in 1 animal, and in another, initial tachypnea was followed by erratic diaphragmatic activity and brief apnea. Laryngeal acid exposure (below pH 2.0) causes laryngospasm and may result in paradoxical apneic events in neonatal dogs. Acid-induced, laryngospasm-associated apnea may represent a potential cause of SIDS, and the immature dog appears to be an excellent model for further investigations.

Fascia augmentation of the vocal fold: graft yield in the canine and preliminary clinical experience.

INTRODUCTION: Glottal insufficiency resulting from vocal fold bowing, hypomobility, or scar is frequently treated by injection augmentation. Injection augmentation with fat, collagen, gel foam, polytef, and recently, fascia lata has been previously reported. Variable graft yield and poor host-tissue tolerance have motivated the continued search for an ideal graft substance. STUDY DESIGN: A prospective trial of autologous fascia augmentation of the vocal cord in the human and in an animal model. METHODS: Autologous fascia injection augmentation (AFIA) was evaluated in 8 canines and 40 patients at our institution between 1998 and 2000. The animal study compared graft yield from AFIA with autologous fat yield. The outcome measure was graft yield calculated from histological examination of larynges 12 weeks after injection augmentation. Clinical trial outcome measures included symptom surveys, acoustical voice analyses, and subjective voice assessments. Mean follow-up was 9 months. RESULTS: In the canine larynx, the mean graft yield for AFIA was 33% (range, 5%-84%) compared with autologous lipoinjection (47%; range, 7%-96%; P =.57). Subjective improvement in vocal quality was reported by 95% of patients (38 of 40) after AFIA. Preoperative and postoperative voice analysis data were obtained from 26 patients. Subjective voice rating demonstrated a significant improvement after AFIA (P <.0001). Acoustical parameters of jitter, shimmer, noise-to-harmonic ratio, phonatory range, and degree unvoiced improved significantly (P <.05) in all patients after fascia augmentation. CONCLUSIONS: Based on the animal study, we concluded that graft yields are excellent but variable for AFIA. The result is similar in variability and overall yield to autologous lipoinjection. Subjective and objective analyses of voice outcomes after AFIA are universally improved. Fascia appears to be an excellent alternative to lipoinjection in properly selected cases of glottic insufficiency.

Velocardiofacial syndrome: incidence of immune cytopenias.

BACKGROUND: Velocardiofacial syndrome (VCFS) is associated with a broad clinical spectrum that frequently overlaps the DiGeorge syndrome. Both have been linked to chromosomal microdeletions of chromosome 22 (22q11.2). DiGeorge syndrome is associated with T-cell dysfunction. What is the incidence of immune cytopenias in children with VCFS? OBJECTIVES: To (1) identify, (2) characterize, (3) quantify, and (4) follow up the immunologic deficits in children initially seen in our institution with VCFS. DESIGN: Prospective clinical evaluation of patients with the features of VCFS. PATIENTS: Twenty consecutive children with the clinical diagnoses of VCFS. SETTING: Tertiary care children's hospital. MAIN OUTCOME MEASURES: All 20 children had genetics evaluation with chromosomal analysis. Immunologic evaluations included serum immunoglobulin concentrations, lymphocyte studies, and mitogen and antigen stimulation studies. RESULTS: Five (25%) of 20 children were noted to have T-cell dysfunction with a clinical presentation marked by recurrent upper respiratory tract infections. Three of these 5 children had resolution of the T-cell dysfunction over a 2-year period. The 2 children with persistent cytopenias combined with immunoglobulin dysfunction required intravenous IgG infusions to control their infections. CONCLUSIONS: Velocardiofacial syndrome is associated with an increased incidence of immune cytopenias and, thus, warrants evaluation in any child with the clinical diagnosis of VCFS. This immune deficit may be transient and depends on the age of the evaluation of the child.