Post-extubation stridor after prolonged intubation in the pediatric intensive care unit (PICU): a prospective observational cohort study.

PURPOSE: Prolonged endotracheal intubation may lead to laryngeal damage, with stridor being the most relevant clinical symptom. Our objective was to determine the incidence of post-extubation stridor and their clinical consequences in children within a tertiary referral center and to identify contributing factors. METHODS: 150 children, aged 0-16 years, intubated for more than 24 h were prospectively enrolled until discharge of the hospital. Potential relevant factors, thought to mediate the risk of laryngeal damage, were recorded and analyzed. RESULTS: The median duration of intubation was 4 days, ranging from 1 to 31 days. Stridor following extubation occurred in 28 patients (18.7%); 3 of them required reintubation due to respiratory distress and in 1 child stridor persisted for which a surgical intervention was necessary. In multivariate analyses, we found the following independent predictors of stridor: intubation on the scene, the use of cuffed tubes and lower age. CONCLUSION: Despite a high incidence for post-extubation stridor, only few children need reintubation or surgical intervention as a result of post-extubation lesions. Intubation on the scene, the use of cuffed tubes and young age are associated with a significant increased risk of post-extubation stridor. Awareness of these factors gives the possibility to anticipate on the situation and to minimize laryngeal injury and its possible future consequences.

Incidence and clinical value of prolonged I-V interval in NICU infants after failing neonatal hearing screening.

Infants admitted to neonatal intensive care units (NICUs) have a higher incidence of perinatal complications and delayed maturational processes. Parameters of the auditory brainstem response (ABR) were analyzed to study the prevalence of delayed auditory maturation or neural pathology. The prevalence of prolonged I-V interval as a measure of delayed maturation and the correlation with ABR thresholds were investigated. All infants admitted to the NICU Sophia Children's Hospital between 2004 and 2009 who had been referred for ABR measurement after failing neonatal hearing screening with automated auditory brainstem response (AABR) were included. The ABR parameters were retrospectively analyzed. Between 2004 and 2009, 103 infants were included: 46 girls and 57 boys. In 58.3% (60 infants) of our population, the I-V interval was recordable in at least one ear at first diagnostic ABR measurement. In 4.9%, the I-V interval was severely prolonged. The median ABR threshold of infants with a normal or mildly prolonged I-V interval was 50 dB. The median ABR threshold of infants with a severely prolonged I-V interval was 30 dB. In conclusion, in case both peak I and V were measurable, we found only a limited (4.9%) incidence of severely prolonged I-V interval (≥0.8 ms) in this high-risk NICU population. A mild delay in maturation is a more probable explanation than major audiologic or neural pathology, as ABR thresholds were near normal in these infants.

Fitting model of ABR age dependency in a clinical population of normal hearing children.

The purpose of this study was to present a simple and powerful fitting model that describes age-dependent changes of auditory brainstem responses (ABR) in a clinical population of normal hearing children. A total of 175 children (younger than 200 weeks postconceptional age) were referred for audiologic assessment with normal ABR results. ABR parameters of normal hearing children between 2003 and 2008 were included. The results of the right ears recorded at 90 dB nHL were analyzed. A simple and accurate fitting model was formulated based on these data. A very similar age-dependent effect was found for peaks III and V, and I-III and I-V intervals; latencies decrease as postconceptional age increases. It shows that the total age-dependent effect will be completed after 1.5-2 years. The age-dependent effect can be modeled by a relatively simple and accurate exponential function. This fitting model can be easily implemented to analyze ABR results of infants in daily clinical practice. We speculate about the underlying physiological processes.

[The child with a tracheostomy, past and present: different indications, different children, different care]. / Het kind met een tracheostoma, vroeger en nu; andere indicaties, andere kinderen, andere zorg.

--Until a few decades ago, acute infectious airway obstruction was the primary indication for tracheotomy in children. Its incidence has decreased considerably due to vaccination programmes and antibiotic treatment. --Today, the primary reasons for performing tracheotomy in a child are chronic airway obstruction (laryngeal injury after intubation, craniofacial malformation, lymphangioma) and prolonged artificial ventilation. --Consequently, the percentage of children who may be decannulated after a short period has decreased. --Tracheotomised children now require longer and more intensive care than before. --Hospital discharge is possible if parents and care providers are provided thorough training and counselling; this process requires specific medical, nursing and psychosocial support. --The increasing proportion of tracheotomised children cared for at home necessitates greater involvement from family practitioners.

Observations in a cohort of infants with severe laryngeal dyskinesia Auditory brainstem response may aid in the diagnosis.

OBJECTIVES: Laryngeal dyskinesia is not a well defined clinical entity, and difficult to distinguish from some other laryngeal disorders. We report on the observations, especially auditory brainstem responses, in a series of infants with laryngeal dyskinesia. METHODS: All infants with laryngeal dyskinesia, diagnosed in Sophia Children's Hospital between 1 January 2000 and 31 June 2003, were included in this retrospective case series study. Auditory brainstem responses were available in most infants. The respiratory, neurological and other symptoms, were recorded. RESULTS: Nine infants were diagnosed with laryngeal dyskinesia. Eight demonstrated severely abnormal auditory brainstem responses (ABR), indicating brainstem dysfunction. Most infants also had serious respiratory, and/or neurological disorders. DISCUSSION: It is hypothesized that laryngeal dyskinesia is a manifestation of a complex neurological disorder localized in the brainstem, comparable with brainstem dysgenesis syndrome. We suggest to use ABR in the diagnosis of unexplained laryngeal obstructive disorders to better define the pathology, and possibly the etiology of the disease.

Long-term quality of life in children after open airway surgery for laryngotracheal stenosis.

OBJECTIVES: The purpose of this study is to evaluate the long-term health related quality of life (HRQoL) in a cohort of children surgically treated for laryngotracheal stenosis (LTS). STUDY DESIGN: Prospective cohort study. METHODS: Parents of children between 4 and 18 years at follow-up completed the Child Health Questionnaire Parent Form (CHQ-PF50). Children between 11 and 18 years at follow-up completed the Child Health Questionnaire Child Form (CHQ-CF87). Biographical and pre-operative data were extracted from the hospital records. Post-operative measurements consisted of the Bruce treadmill test and pulmonary function testing (PFT). RESULTS: Fifty-four parents completed the CHQ-PF50; twenty-one children completed the CHQ-CF87. The CHQ-PF50 was significantly worse than the norm population on the subscales physical functioning, role functioning: emotional/behavior, general health perceptions, family activities, parental impact: emotional, and time. CHQ-CF87 was significantly worse than the norm population on physical functioning and better on mental health. After multivariate analysis, presence of co-morbidities and glottic stenosis are the most important pre-operative factors for worse scores on general health. As post-operative measurements, the Bruce treadmill test and peak expiratory flow (PEF) correlate well with HRQoL physical subscales. CONCLUSIONS: At long-term follow-up after treatment for LTS, deficits in HRQoL may still exist. Presence of co-morbidities and glottic stenosis are important negative factors for long-term HRQoL. The Bruce treadmill test and peak expiratory flow on pulmonary function testing correlate well with physical subscales on HRQoL. A long-term multidisciplinary follow-up with assessment of HRQoL is advised in patients treated for LTS. LEVEL OF EVIDENCE: 2B, individual prospective cohort study.

Acoustic simulation of a patient's obstructed airway.

This research focuses on the numerical simulation of stridor; a high pitched, abnormal noise, resulting from turbulent airflow and vibrating tissue through a partially obstructed airway. Characteristics of stridor noise are used by medical doctors as indication for location and size of the obstruction. The relation between type of stridor and the various diseases associated with airway obstruction is unclear; therefore, simply listening to stridor is an unreliable diagnostic tool. The overall aim of the study is to better understand the relationship between characteristics of stridor noise and localization and size of the obstruction. Acoustic analysis of stridor may then in future simplify the diagnostic process, and reduce the need for more invasive procedures such as laryngoscopy under general anesthesia. In this paper, the feasibility of a coupled flow, acoustic and structural model is investigated to predict the noise generated by the obstruction as well as the propagation of the noise through the airways, taking into account a one-way coupled fluid, structure, and acoustic interaction components. The flow and acoustic solver are validated on a diaphragm and a simplified airway model. A realistic airway model of a patient suffering from a subglottic stenosis, derived from a real computed tomography scan, is further analyzed. Near the mouth, the broadband noise levels at higher frequencies increased with approximately 15-20 dB comparing the stridorous model with the healthy model, indicating stridorous sound.

Short use of muscle relaxants following single stage laryngotracheoplasty in children.

OBJECTIVE: The postoperative management of children undergoing single stage laryngotracheoplasty (SSLTP) includes intubation and muscle paralysis to secure the airway and protect the wound. We reduced the period of postoperative muscle paralysis in an attempt to decrease the incidence of pulmonary complications. The objective of this study was to evaluate the influence of the duration of muscle paralysis on pulmonary complications and outcome. METHODS: Medical records of all children admitted, between 1994 and 2002, to the pediatric intensive care unit following SSLTP were analysed. Children were grouped according to the number of days muscle paralysis was used. RESULTS: Thirty-six children (15 male, 21 female, mean age 32 months (9-162 months)) underwent SSLTP for laryngeal stenosis. Prior to surgery 29 needed a tracheotomy (mean duration 11.1 months). Shorter muscle paralysis leads to shorter intubation and mechanical ventilation and therefore PICU and hospital length of stay were 12.4 and 9.9days shorter in the group with short use of muscle paralysis (p<0.001 and p=0.002, respectively). There was no significant difference in postoperative complications, but a trend towards fewer atelectases in children with short muscle paralysis could be recognised. Postoperatively we observed no auto-extubations in either group and success rate of SSLTP was comparable in both groups (94 and 95%). CONCLUSION: Children undergoing SSLTP can safely benefit from a postoperative strategy using a short duration of muscle relaxants. They have fewer days on mechanical ventilation with a concomitant decrease in duration of hospital stay.

Elective cricothyroidotomy.

Cricothyroidotomies instead of tracheostomies were performed in 61 adult patients over a period of two years. The indications were as for tracheostomy. The majority of the patients had severe trauma, respiratory problems and sepsis. The procedure was to be found easy and fast. There were no severe complications during or directly after the operation. Of the 23 surviving patients 7 were lost for follow up, 16 patients were reexamined 6 months after decannulation. No serious complications had developed, although 2 patients had minor granulation tissue formation at the stoma site and 1 had a minimal anterior narrowing of the subglottic region without granulation tissue. None of these patients needed treatment.

Laser myringotomy versus ventilation tubes in children with otitis media with effusion: a randomized trial.

OBJECTIVES: Insertion of ventilation tubes in children with otitis media with effusion (OME) is an accepted and common treatment procedure. The majority of patients require general anesthesia. Although laser myringotomy can be performed in local anesthesia, evidence is lacking that this treatment modality is an alternative for tubes, and outcome predictors for laser myringotomy are not available. STUDY DESIGN: Prospective randomized trial. METHODS: We screened 1,403 children with chronic OME that were indicated for placement of ventilation tubes. In the eligible patients, we performed laser myringotomy in one ear and placed a tube in the other ear, both within the same patient. Follow-up was scheduled each month for 6 months. Success was defined as absence of effusion or aural discharge. A logistic regression model was used with success of the therapy as binary outcome. This model was based on base-line variables, asked for in a parent's questionnaire. RESULTS: Two hundred eight children received the allocated intervention, and no complications occurred. The mean closure time of the laser perforation was 2.4 weeks, and the mean patency time of the ventilation tube was 4.0 months. The mean success rate was 40% for laser and 78% for tubes. Ten known variables were found to predict middle ear status after therapy. CONCLUSION: Laser myringotomy is a safe but less-effective procedure than insertion of a ventilation tube in the treatment of chronic OME. The prognostic model enables the otolaryngologist to choose the surgical treatment for the child that benefits most: laser myringotomy or ventilation tube.

Pediatric laryngobronchoscopy. 1332 procedures stored in a data base.

Laryngobronchoscopy (LBS), using both rigid and flexible bronchoscopes, has become a frequently performed operation in children. A data base was established to enable retrospective evaluation of a large number of LBSs carried out in a pediatric center. Experience with 1332 cases of LBS involving 808 patients over an 8-year period is presented. The main indications for LBS were inspiratory stridor, atelectasis, and suspected foreign body aspiration. Most frequent diagnoses at LBS were bronchopneumonia, intubation trauma, tracheomalacia, laryngomalacia, and foreign body aspiration. Only 25 complications occurred (1.9%) including two cases of xylometazoline intoxication.

Fiberoptic laryngoscopy under general anesthesia in neonates.

In the Sophia Children's Hospital we perform fiberoptic laryngoscopy in neonates under general anesthesia without the use of muscle relaxants in the diagnostics of functional laryngeal disorders. The necessary diagnostic and anesthetic equipment is described. Special attention is paid to the way in which the fiberscope is introduced into the breathing circuit and into the child's airway. Several advantages over other methods are discussed. The procedure has proved to be easy, safe and informative.

Therapeutic reintubation for post-intubation laryngotracheal injury in preterm infants.

The failure to extubate a preterm infant after prolonged intubation is often caused by laryngotracheal injury. This condition is treated by tracheotomy, anterior cricoid split, or often, by reintubation and subsequent extubation attempts in a later stage. To assess the value of reintubation as treatment of post-intubation injury, we retrospectively studied a group of preterm infants from the neonatal intensive care unit in the Sophia Children's Hospital. Three categories of injury were distinguished according to the findings at laryngobronchoscopy: (a) edema or superficial lesions, (b) ulcerations and edema and (c) granulations. Twenty-three infants were therapeutically reintubated after post-intubation injury was diagnosed, for a mean period of 17 days. The therapy was successful in 22 patients, and a failure in one. The follow-up period was a mean 34 months. The result and the duration of the treatment vary with the category of the injury and the condition of the patient. Therapeutic reintubation is compared with alternatives such as anterior cricoid split and tracheotomy. We conclude that reintubation is a valuable therapy that should precede the decision for surgery.

Complications of rigid laryngo-bronchoscopy in children.

Twenty-five complications (of which 2 were lethal) occurred in 1332 rigid laryngo-bronchoscopies performed under general anesthesia in the Sophia Children's Hospital during an 8 year period (1982-1990). The nature and circumstances of these complications were studied retrospectively. Important intraoperative complications were hemorrhage and cardiac arrhythmia; postoperative complications were intoxication and respiratory complications. Three risk factors: tetralogy of Fallot, biopsy/drainage, and extraction of an aspirated foreign body appeared to be significantly associated with complications. The results of this study were compared with those reported in studies of rigid and flexible laryngo-bronchoscopies in children.

Management of infantile subglottic hemangioma: laser vaporization, submucous resection, intubation, or intralesional steroids?

The infantile subglottic hemangioma can be treated in various ways. The results of the treatment used in the Sophia Children's Hospital, intralesional steroids and intubation (IS + I), are discussed and compared with the results of other current treatment methods: CO2 laser vaporization, submucous resection and intubation alone. A total of 18 infants were treated for subglottic hemangioma in our hospital: ten with IS + I alone, five were first treated with systemic therapy and later with IS + I alone and three with various therapies. IS + I was effective in 14 of the 15 patients, one patient was lost from follow up. The remaining three infants were treated with (combinations of) various therapies, because IS + I failed or was not tried. Two patients were finally cured, one still has a tracheotomy. Of other current therapies, CO2 laser vaporization is reported to be effective. In all 30% of the infants treated in Boston Children's Hospital with CO2 laser needed a tracheotomy. Moreover subglottic stenosis is a serious complication. Submucous resection is often successful. It may be complicated by subglottic stenosis and in some cases, depending on the localization of the hemangioma, it may be contraindicated. Intubation alone is less effective than intubation combined with intralesional steroids. Management of subglottic hemangioma in Sophia Children's Hospital is primarily intralesional steroids and intubation and secondarily submucous resection or tracheotomy. CO2 laser vaporization is seldom applied because of the risk of subglottic stenosis.

Pitfalls in preoperative management of acquired laryngeal stenosis. The problem of the hidden obstruction in the airway.

Most acquired laryngeal stenoses in infants and children can be treated surgically with successful outcome. We describe two patient cases in which removal of such a stenosis did not result in decanulation, because another, hidden obstruction was present. This demonstrates the importance of preoperative assessment to indicate factors that influence the outcome of surgery, especially in infants with a syndrome. Guidelines for preoperative management and an extensive list of syndromes in which a hidden obstruction can be suspected, are presented.

Acquired laryngeal stenosis in infants and children treated by laryngofissure and stenting.

Thirty young patients with acquired laryngeal stenosis were treated by means of a laryngofissure and stenting. The age distribution suggested two subgroups: infants aged 0-2 years (n = 24), and children aged 6-16 years (n = 6). The causes of the stenosis and the treatment results were different in these subgroups. Treatment resulted in successful decannulation in 22 of 24 infants, and in 5 of 6 children. Treatment included a re-operation in two patients. In 1 patient the therapy failed, and 2 patients died after fatal complications. Decannulation rate, duration of the tracheotomy, and the number of re-operations compare favorably to the results of other centers. The longer duration of stenting, and the high mortality rate may be considered disadvantages.

OSAS in craniofacial syndromes: an unsolved problem.

Although the incidence of Obstructive Sleep Apnea syndrome (OSAS) in craniofacial syndromes is high, it is often not recognized and thus not treated. In order to study the diagnostics and treatment options for these patients, we studied a group of 72 patients treated in our hospital for Apert, Crouzon, or Pfeiffer syndrome, and compared our findings with the literature. There appears to be agreement on polysomnography (PSG) and airway endoscopy as the main diagnostic options, but therapies are very diverse. Early diagnostics and prompt therapy will prevent serious complications.

Subglottic hemangiomas in infants: treatment with intralesional corticosteroid injection and intubation.

Six children with a subglottic hemangioma were treated in the Sophia Children's Hospital in the period 1982-1987 by means of intralesional corticosteroid injection, followed by intubation. After treatment all children were symptomfree. In 3 patients this result was attained after 1 injection, in 2 after 3 injections. One patient needed 5 injections. The average duration of intubation was 19 days (7-36). Three months (1/2-7 1/2) after the onset of therapy all patients were free of symptoms. No serious complications were observed. No patient needed a tracheotomy. The average follow-up period was 3.3 years (1 1/2-5 1/2). The authors feel that not only the effect of intralesional corticosteroids, but also local gentle pressure by the tube is of therapeutic importance. The above-mentioned treatment of subglottic hemangioma in children is now the treatment of choice in our clinic.

A pilot case control follow-up study on hearing in children treated with tobramycin in the newborn period.

OBJECTIVE: To assess the occurrence of hearing loss in children due to neonatal exposure to long courses of tobramycin and/or high tobramycin serum concentrations. METHODS: This was a pilot case-control study in 3-4-year old children. Data on tobramycin administration were abstracted from the patient files of an earlier study. Patients exposed in the neonatal period to either long courses (>7 days) or high serum concentrations of tobramycin constituted the study group. The control group consisted of patients without tobramycin exposure. Patients were matched for other risk factor according to criteria of the joint committee on infant hearing. All patients underwent the following investigations: otoscopy and pneumatic otoscopy, followed by impedance audiometry, to exclude middle ear effusion. Click-evoked oto-acoustic emissions (ce-OAE) as well as distortion product oto-acoustic emissions (dp-OAE), tested at f2 frequencies ranging from 1 to 10 kHz, were measured to assess hearing. All patients with abnormal ce-OAE results underwent brainstem electric response audiometry (BERA) as well. Since aminoglycoside ototoxicity is usually bilateral, results were compared per patient and not per ear. RESULTS: A total of 29 patients were tested. Eleven patients were excluded due to middle ear effusion. Data for 18 patients were analyzed. In the tobramycin treated group (n=9) both ce-OAE and dp-OAE (at all tested frequencies) were not detectable in six ears of three patients. All other patients had normal ce-OAE's as well as normal dp-OAE's in this frequency range. Difference between the tobramycin treated and control group for OAE as well as dp-OAE showed a trend (P=0.08). In all three patients with undetectable emissions BERA confirmed a cochlear loss of 60-70 dB at 3 kHz in both ears. These three patients had the longest total exposure to tobramycin: 20-24 days and 84-92 mg/kg, respectively. No relation to either peak or trough serum concentrations could be detected. CONCLUSION: There was no statistical relation between hearing loss and tobramycin exposure, probably due to sample size. Our results do indicate a need for a case-control follow-up study of hearing in neonates exposed to long courses of aminoglycosides.