Iatrogenic tracheobronchial perforation in infants

Retrocardiac Pneumomediastinum: Description of an Unusual Case and Review of Literature

Retrocardiac pneumomediastinum (RP) is the consequence of air trapping in the inferior and posterior mediastinum. It is characterized by the presence of a right or left para-sagittal infrahilar oval or pyramidal air collection on a chest X-ray. It is usually detected in neonates because of alveolar rupture after invasive ventilation or invasive manoeuvres applied on airways or the digestive tract. A healthy child came to the emergency department (ED) for acute respiratory failure due to viral bronchiolitis when he was 2 months old. Because of his clinical condition, he underwent helmet continuous positive airway pressure (HCPAP). When the condition allowed, he was discharged and sent home. He was re-admitted into the hospital for asthmatic bronchitis 3 months later. A frontal chest X-ray taken during the second hospitalization showed an oval-shaped retrocardiac air lucency not previously detected. Differential diagnosis including digestive and lung malformations was made. Finally, the diagnosis of RP was made. We report an unusual case of retrocardiac pneumomediastinum in a 5-month-old male infant after the application of continuous positive pressure via a helmet. RP presentation after the administration of non-invasive ventilatory support beyond the neonatal age is unusual. Although surgical drainage is curative, conservative treatment can be considered in hemodynamically stable patients.

Nebulised surfactant to reduce severity of respiratory distress: a blinded, parallel, randomised controlled trial

OBJECTIVE

To evaluate if nebulised surfactant reduces intubation requirement in preterm infants with respiratory distress treated with nasal continuous positive airway pressure (nCPAP).

DESIGN

Double blind, parallel, stratified, randomised control trial.

SETTING

Sole tertiary neonatal unit in West Australia.

PATIENTS

Preterm infants (29⁰-33⁶ weeks' gestational age, GA) less than 4 hours of age requiring 22%-30% supplemental oxygen, with informed parental written consent.

INTERVENTIONS

Infants were randomised within strata (29⁰-31⁶ and 32⁰-33⁶ weeks' GA) to bubble nCPAP or bubble nCPAP and nebulised surfactant (200 mg/kg: poractant alfa) using a customised vibrating membrane nebuliser (eFlow neonatal). Surfactant nebulisation (100 mg/kg) was repeated after 12 hours for persistent supplemental oxygen requirement.

MAIN OUTCOME MEASURES

The primary outcomes were requirement for intubation and duration of mechanical ventilation at 72 hours. Data analysis followed the intention-to-treat principle.

RESULTS

360 of 606 assessed infants were eligible; 64 of 360 infants were enrolled and randomised (n=32/group). Surfactant nebulisation reduced the requirement for intubation within 72 hours: 11 of 32 infants were intubated after continuous positive airway pressure (CPAP) and nebulised surfactant compared with 22 of 32 infants receiving CPAP alone (relative risk (95% CI)=0.526 (0.292 to 0.950)). The reduced requirement for intubation was limited to the 32⁰-33⁶ weeks' GA stratum. The median (range) duration of ventilation in the first 72 hours was not different between the intervention (0 (0-62) hours) and control (9 (0-64) hours; p=0.220) groups. There were no major adverse events.

CONCLUSIONS

Early postnatal nebulised surfactant may reduce the need for intubation in the first 3 days of life compared with nCPAP alone in infants born at 29⁰-33⁶ weeks' GA with mild respiratory distress syndrome. Confirmation requires further adequately powered studies.

TRIAL REGISTRATION NUMBER

ACTRN12610000857000.

Iatrogenic injury and unexpected hospital death in the newborn

Neonates are unusually vulnerable to iatrogenic injury due to small body size, delicate tissues, and immature immune systems. Investigation of an unexpected neonatal death in the hospital should begin with a review of the medical record and discussion with medical staff involved in the patient׳s care. Postmortem investigation should include a complete and well-documented autopsy. Additional investigations, such as microbiological studies and chemical and toxicological studies of postmortem and antemortem fluid samples, may be crucial in arriving at a diagnosis. Causes of iatrogenic injury include birth trauma, medication errors and adverse drug effects, hospital-acquired infection, and medical device malfunction, incorrect placement, and misuse. Autopsy is an important tool for understanding the cause of an unexpected death, improving the quality of care, and providing closure to parents and family.

Aerosolized KL4 surfactant improves short-term survival and gas exchange in spontaneously breathing newborn pigs with hydrochloric acid-induced acute lung injury

BACKGROUND

Surfactant therapy may be beneficial in acute lung injury (ALI). In spontaneously breathing newborn pigs with ALI supported with continuous positive airway pressure (CPAP), we evaluated the hypothesis that aerosolized KL4 surfactant (AERO KL4 S) would provide a similar therapeutic effect as intratracheal KL4 surfactant (ETT KL4 S) when compared to controls.

METHODS

We randomized pigs with HCl-induced ALI to: (1) 175 mg/kg KL4 surfactant via endotracheal tube (ETT); (2) AERO KL4 S (22.5 mg/min phospholipid) for 60 min via continuous positive airway pressure (CPAP); or (3) sham procedure on CPAP. We obtained physiologic data and arterial blood gases throughout the 3-hr study. At study end, lungs were excised for analysis of interleukin-8 (IL-8), myeloperoxidase (MPO) levels and histomorphometric data.

RESULTS

Pigs treated with ETT KL4 S and AERO KL4 S had improved survival and sustained pO2 compared to controls. The AERO KL4 S group had higher pH compared to controls. Lung IL-8 levels were lower in the AERO KL4 S group compared to controls. Histomorphometric analysis showed less hemorrhage in the ETT and AERO KL4 S groups compared to controls. The AERO KL4 S group had more open lung units per fixed-field than the ETT KL4 S or controls.

CONCLUSIONS

AERO KL4 S produced similar improvements in survival, physiology, inflammatory markers, and morphology as ETT KL4 S in an ALI model.

An open label, pilot study of Aerosurf® combined with nCPAP to prevent RDS in preterm neonates

BACKGROUND

Nasal continuous positive airway pressure (nCPAP) is an accepted mode of respiratory support for preterm infants with respiratory insufficiency. To avoid potential sequelae of endotracheal (ET) intubation and mechanical ventilation, prophylactic aerosolization of surfactant delivered via nCPAP has been attempted with limited success.

METHODS

To determine the feasibility and safety of prophylactic aerosolization of a peptide-containing synthetic surfactant, Aerosurf® (lucinactant for inhalation) was delivered by nCPAP to preterm infants at risk for respiratory distress syndrome (RDS). Neonates were enrolled into treatment group 1 (Aerosurf retreatment separated by at least 3 h) or treatment group 2 (Aerosurf retreatment separated by at least 1 h). A vibrating membrane nebulizer Aeroneb Pro® was used to aerosolize 20 mg/mL Aerosurf. All neonates received the initial 3-h treatment, and three retreatments were permitted within 48 h based on clinical response.

RESULTS

Seventeen infants were enrolled. Aerosurf was well tolerated, with transient desaturations observed during dosing without bradycardia or hypotension. Variability in output rates of the Aeroneb Pro was observed leading to different average dispensed drug volumes per treatment per patient. All infants survived; 29.4% required subsequent ET surfactant replacement therapy, 23.5% were diagnosed with RDS at 24 h, and 11.8% with bronchopulmonary dysplasia (BPD) at 28 days of life. Mean FiO₂ was 0.4 at baseline, and 0.32 at 4 h posttreatment.

CONCLUSIONS

Aerosurf can be safely administered via nCPAP in preterm infants at risk for RDS and may provide an alternative to surfactant administration via an ET tube. Further studies are required to evaluate this delivery approach.

Aerosolized surfactants

PURPOSE OF REVIEW

To present existing data on the potential use of aerosolized surfactants for treatment of neonatal respiratory distress syndrome in the era of noninvasive ventilatory support.

RECENT FINDINGS

Current surfactant therapy requires endotracheal intubation and application of positive pressure ventilation. Instillation of the drug itself can be complicated by 'peridosing adverse events' including, but not limited to, desaturations, bradycardias, changes in blood pressure, drug reflux and even the need for reintubations. Increasing use of noninvasive ventilatory support for neonatal respiratory distress syndrome has motivated clinicians and researchers to look for alternate ways of introducing surfactants to patients. Aerosolized surfactants have been tested in animal models of respiratory distress syndrome. In addition, four small clinical studies have been performed to date. The effectiveness of this form of treatment requires further study, however, which will need to include optimizing the dose of aerosolized surfactant, choosing particle size, developing the best delivery system, and using a surfactant formulation that maintains its activity once aerosolized.

SUMMARY

Aerosolized surfactants for neonatal respiratory distress syndrome may prevent the need for endotracheal intubation. Appropriately designed randomized controlled studies are required to determine if this form of surfactant administration is as effective and safe as tracheal instillation.

Isolated tracheal rupture caused by blunt trauma and the importance of early diagnosis: a case report

Tracheal rupture usually occurs after blunt traumas. Isolated tracheal rupture is an extremely rare condition. The diagnosis of isolated tracheal rupture is very important for treatment and prognosis. Physical examination and imaging techniques should be used to make the diagnosis. Lateral neck and chest X-rays are very important for early diagnosis. Other techniques are thorax, neck tomography and bronchoscopy. In this paper we present a case of isolated tracheal rupture and discuss the early diagnostic techniques used.

Spontaneous tracheal and subglottic tears in neonates

OBJECTIVES/HYPOTHESIS

Spontaneous rupture of the trachea or subglottis as a complication of difficult delivery has not been reported in the United States literature. There have been a few cases reported in the European literature. The present report describes a series of newborns with this complication and discusses the signs and treatment options of this difficult, life-threatening problem.

STUDY DESIGN

Retrospective review.

METHODS

Newborns born between 1996 and 2001 who were treated for spontaneous subglottic or tracheal rupture at a tertiary care children's hospital neonatal intensive care unit were reviewed.

RESULTS

Four cases of spontaneous subglottic rupture were seen at the hospital. In three of the four cases the tracheas were intubated on an emergency basis after subcutaneous air was noted in the anterior aspect of the neck. In the fourth patient the trachea was not intubated until the subglottic tear was visualized intraoperatively. Two of the four patients died. One died without securing of an airway; the other died of complications of prolonged hypoxia. Eight cases from European literature of spontaneous neonatal subglottic and tracheal tears are reviewed and are compared with the cases presented in the current report.

CONCLUSIONS

Early detection of airway rupture by flexible endoscopy is essential for timely diagnosis and appropriate treatment. Standard endotracheal intubation can exacerbate the problem and should be deferred if possible until direct airway visualization can be accomplished. Signs associated with tracheal tears include subcutaneous emphysema, respiratory distress, pneumothorax, and pneumomediastinum. These should lead to emergent consultation with otolaryngologists for examination and securing of the airway.

Imaging of medical disease of the newborn lung

Surfactant deficiency remains the most common and serious pulmonary affliction of premature infants. Exogenous surfactant and corticosteroid administration have had a major impact in improving survival and morbidity in this disease with consequent alterations in the clinical and radiographic course. Chronic lung disease, although still common, is usually less severe than previously, especially in larger infants. Significant therapeutic strides in treating persistent pulmonary hypertension with or without meconium aspiration have been the use of high-frequency ventilators, inhaled nitric oxide, and ECMO. Prompt recognition and treatment of infection, atelectasis, and air leak whether primary or secondary are important to overall outcome. Less common pulmonary conditions, such as lymphangiectasia, pulmonary hypoplasia, and alveolar proteinosis, may initially masquerade as more common lesions. Persistent pulmonary hypertension is often the initial diagnosis and part of the clinical problem. Attention must be paid to the clinical and radiographic appearance and excursion of the thoracic cage because deformities and malformations may be the cause of respiratory problems.