Alessandro Amaddeo

Long-term non-invasive ventilation in children.

Use of long-term non-invasive ventilation is increasing exponentially worldwide in children of all ages. The treatment entails delivery of ventilatory assistance through a non-invasive interface. Indications for use of non-invasive ventilation include conditions that affect normal respiratory balance (eg, those associated with dysfunction of the central drive or respiratory muscles) and disorders characterised by an increase in respiratory load (eg, obstructive airway or lung diseases). The type of non-invasive ventilation used depends on the pathophysiological features of the respiratory failure. For example, non-invasive ventilation will need to either replace central drive if the disorder is characterised by an abnormal central drive or substitute for the respiratory muscles if the condition is associated with respiratory muscle weakness. Non-invasive ventilation might also need to unload the respiratory muscles in case of an increase in respiratory load, as seen in upper airway obstruction and some lung diseases. Technical aspects are also important when choosing non-invasive ventilation-eg, appropriate interface and device. The great heterogeneity of disorders, age ranges of affected children, prognoses, and outcomes of patients needing long-term non-invasive ventilation underline the need for management by skilled multidisciplinary centres with technical competence in paediatric non-invasive ventilation and expertise in sleep studies and therapeutic education.

Polygraphic respiratory events during sleep in children treated with home continuous positive airway pressure: description and clinical consequences.

OBJECTIVE Data are scarce on respiratory events during sleep for children treated at home with continuous positive airway pressure (CPAP). The present study aimed to characterize the respiratory events with CPAP during sleep and to analyze their clinical consequences. PATIENTS/METHODS Consecutive polygraphies (PG) performed on stable children treated with CPAP were analyzed and scored using SomnoNIV Group definitions. For every respiratory event, the presence of a 3% oxygen desaturation and/or an autonomic arousal was systematically searched. Nocturnal gas exchange was assessed using summary data of oximetry and transcutaneous carbon dioxide pressure recordings. RESULTS Twenty-nine consecutive polygraphies, performed on 26 children (mean age 7.8 ± 6.2 years, mean CPAP use 10.6 ± 14.4 months), were analyzed. The index of total respiratory events was low (median value 1.4/h, range 0-34). The mean number of different types of respiratory events per PG was 2 ± 1 (range 0-4), with always a predominant event. Partial or total upper airway obstruction without a decrease in ventilatory drive was the most frequent event and was the most frequently associated with an oxygen desaturation (in 30% of the events) and an autonomic arousal (in 55% of the events). Weak correlations were observed between nocturnal oximetry and PG results. CONCLUSIONS The index of respiratory events during CPAP treatment for stable children is low. As these events may be associated with an oxygen desaturation or an autonomic arousal, and as nocturnal gas exchange cannot predict PG results, a systematic sleep study seems justified for the routine follow-up of children treated with CPAP.

Long term continuous positive airway pressure (CPAP) and noninvasive ventilation (NIV) in children: Initiation criteria in real life

Long term noninvasive continuous positive airway pressure (CPAP) and noninvasive ventilation (NIV) are increasingly used in children but limited information is available on the criteria and conditions leading to the initiation of these treatments. The aim of the study is to describe the objective overnight respiratory parameters and clinical situations that led to the initiation of CPAP/NIV in a pediatric NIV unit.

Sleep-disordered breathing and its management in children with achondroplasia

Sleep‐disordered breathing is a common feature in children with achondroplasia. The aim of our study was to review the poly(somno)graphic (P(S)G) findings and consequent treatments in children with achondroplasia followed in the national reference center for skeletal dysplasia. A retrospective review of the clinical charts and P(S)G of 43 consecutive children (mean age 3.9 ± 3.5 years) with achondroplasia seen over a period of 2 years was performed. Twenty four (59%) children had obstructive sleep apnea (OSA). Thirteen children had an obstructive apnea‐hypopnea index (OAHI) < 5/hr, four had an OAHI between 5 and 10/hr, and seven had an OAHI ≥ 10/hr. Ten of the 15 children who had previous upper airway surgery still had an abnormal P(S)G. All the patients with an AHI ≥ 10/hr were under 7 years of age and none had a prior tonsillectomy. The children who underwent adeno‐tonsillectomy, coupled in most cases with turbinectomy, were significantly older (mean age 7.5 ± 3.5 vs. 3.5 ± 1.7 years old, P = 0.015) and had significantly better P(S)G results than those who underwent only adeno‐turbinectomy. No correlation was observed between the mean AHI value at the baseline P(S)G and the type of academic course (standard, supported or specialized). In conclusion, OSA is common in children with achondroplasia. The observation of a reduced prevalence of OSA after (adeno‐)tonsillectomy is in favor of this type of surgery when possible.

Central sleep apnea in children: experience at a single center.

OBJECTIVE Central sleep apnea (CSA) syndromes are rare in children and data in children over one year of age are scarce. The aim of the study was to describe the sleep characteristics, underlying disorders, management, and outcome of children with CSA. PATIENTS/METHODS A retrospective chart review of all children >1 year of age, diagnosed with CSA on a laboratory sleep study during a 20-month period, was performed. CSA was defined by a central apnea index (CAI) >5 events/h. The clinical management and the patients outcome were analyzed. RESULTS Eighteen of 441 (4.1%) patients recorded during the study period had CSA. The median CAI, pulse oximetry, and oxygen desaturation index were 13/h (range 6-146), 96% (93-98%), and 18/h (6-98), respectively. Neurosurgical pathologies represented the most common underlying disorders with Arnold-Chiari malformation in four and ganglioglioma in three patients. Other underlying disorders were Prader-Willi syndrome (N = 3), achondroplasia (N = 2), and Down syndrome, with one patient having an achondroplasia and a Down syndrome. The remaining six patients had other genetic diseases. The most common investigation was brain magnetic resonance imaging (MRI). Individualized management with neurosurgery and/or chemotherapy, continuous positive airway pressure (in two patients having associated obstructive events), or noninvasive ventilation resulted in an improvement in CSA and the clinical presentation in 11 patients. CONCLUSION CSA is rare in children >1 year of age. Underlying disorders are dominated by neurosurgical disorders. Individualized management is able to improve CSA and the clinical condition in most patients.

Interfaces for noninvasive ventilation in the acute setting in children

The use of noninvasive ventilation (NIV) is very specific in the acute setting as compared to its use in a chronic setting. In the Pediatric Intensive care Unit (PICU), NIV may be required around the clock and initiation has to be fast and easy. Despite the increasing use of non-invasive ventilation (NIV) and the larger choice of interfaces, data comparing the use of different interfaces for pediatric patients are scarce and recommendations for the most appropriate choice of interface are lacking. However, this choice in acute settings is crucial and a major contributor of the success of NIV. The aim of the present review was to describe the different types of interfaces available for children in the acute setting, their advantages and limitations, to highlight how to choose the optimal interface, and how to monitor the tolerance of the interface.

Sleep study as a diagnostic tool for unexplained respiratory failure in infants hospitalized in the PICU

Purpose: The aim of the study was to analyze the diagnostic and therapeutic value of a polygraphy (PG) in infants hospitalized for unexplained respiratory failure or life‐threatening events in the PICU. Material and methods: The PG of 13 infants (4 girls), mean age 6.8 ± 7.7 months, were analyzed. Results: Eight infants were admitted for unexplained respiratory failure and 5 for life‐threatening events. PG showed features suggestive of respiratory muscle weakness in 5 infants whose final diagnoses were nemaline rod myopathy (n = 2), congenital myasthenia (n = 2), and diaphragmatic dysfunction (n = 1). Four of these patients were successfully treated with noninvasive ventilation (NIV). PG was suggestive of brainstem dysfunction in 4 infants; 2 were treated successfully with NIV and another with caffeine. PG showed obstructive sleep apnea in 3 infants; 2 were treated successfully with NIV and one patient was lost during follow up. A typical pattern of congenital central hypoventilation syndrome was observed in the last patient who was treated successfully with invasive ventilation. One patient with diaphragmatic dysfunction and one with brain stem dysfunction died. Conclusions: PG may assist the diagnosis and guide the management of unexplained respiratory failure or life‐threatening events in infants hospitalized in the PICU.

Obstructive sleep apnea in Down syndrome: Benefits of surgery and noninvasive respiratory support

Children with Down syndrome are at increased risk of obstructive sleep apnea (OSA). The aim of the study was to describe the management of OSA in a large cohort of children with Down syndrome. A retrospective analysis of sleep studies and consequent management was performed for all consecutive Down syndrome patients evaluated between September 2013 and April 2016. The data of 57 patients were analyzed: 51/53 had an interpretable overnight polygraphy and 4 the recording of nocturnal gas exchange. Mean age at baseline sleep study was 6.2 ± 5.9 years. Eighteen patients (32%) had prior upper airway surgery. Mean apnea‐hypopnea index (AHI) was 14 ± 16 events/hr with 41 of the 51 (80%) patients having OSA with an AHI >1 event/hr and 20 patients (39%) having an AHI ≥10 events/hr. Consequently, eight patients (14%) had upper airway surgery. OSA improved in all patients except two who needed noninvasive respiratory support. Nineteen (33%) patients required noninvasive respiratory support. Mean age at noninvasive respiratory support initiation was 7 ± 7 years. On 11 patients with objective adherence data available, mean compliance at 2 ± 1 years of treatment was excellent with an average use per night of 8 hr46 ± 3 hr59 and 9 patients using the noninvasive respiratory support >4 hr/night. Noninvasive respiratory support was associated with an improvement of nocturnal gas exchange. The prevalence of OSA is high in Down syndrome. Upper airway surgery is not always able to correct OSA. Noninvasive respiratory support represents then an effective treatment for OSA and good compliance may be achieved in a majority of patients.

Whistle and cough pressures in children with neuromuscular disorders.

RATIONALE Expiratory muscle strength is a determinant of cough function. Maximal static expiratory pressure (PEmax) manoeuvres are widely used but are limited by patient motivation and technique. The study hypothesized that whistle mouth (PmW) and cough gastric (PgasCough) pressures might provide additional tests of expiratory muscle strength in children and young adults with neuromuscular disease (NMD). METHODS We retrospectively reviewed the data of lung function and respiratory muscle tests of all the patients with NMD followed in our centre between November 2001 and December 2013. PmW and PgasCough were compared to other common tests. RESULTS Three hundred and four respiratory evaluations were performed in 143 patients, aged 3-29 years old. Seventy-two patients had 2 to 8 evaluations. Median [interquartiles] PEmax (38 [28-54] cmH2O) did not differ significantly from PgasCough (45 [30-60] cmH2O) and both were significantly greater than PmW (30 [19-44] cmH2O). Significant good correlations were observed between all the expiratory muscle parameters. The best correlation was observed between PEmax and PmW (r = 0.812, p < 0.001). Moreover, good correlations were found between the percentage of predicted forced vital capacity and PmW (r = 0.619, p < 0.001) and PgasCough (r = 0.568, p < 0.001). Concerning the whistle test, the non-invasive measurement highly correlated with invasive measurements. CONCLUSIONS PmW and PgasCough are simple and valuable tests to assess expiratory muscle strength in children and young adults with NMD. These tests are particularly useful in children having difficulties to perform PEmax manoeuvre. They have the great advantage of their simplicity, but PgasCough is limited by its invasiveness.

Oxygen and carbon dioxide monitoring during sleep

Monitoring of oxygen and carbon dioxide (CO2) is of crucial importance during sleep-disordered breathing in order to assess the consequences of respiratory events on gas exchange. Pulse oximetry (SpO2) is a simple and cheap method that is used routinely for the recording of oxygen levels and the diagnosis of hypoxemia. CO2 recording is necessary for the diagnosis of alveolar hypoventilation and can be performed by means of the end-tidal (PetCO2) or transcutaneous CO2 (PtcCO2). However, the monitoring of CO2 is not performed on a routine basis due to the lack of simple, cheap and reliable CO2 monitors. This short review summarizes some technical aspects of gas exchange recording during sleep in children before discussing the different definitions of alveolar hypoventilation and the importance of CO2 recording.