Efficacy of a new technique - INtubate-RECruit-SURfactant-Extubate - "IN-REC-SUR-E" - in preterm neonates with respiratory distress syndrome: study protocol for a randomized controlled trial

Background

Although beneficial in clinical practice, the INtubate-SURfactant-Extubate (IN-SUR-E) method is not successful in all preterm neonates with respiratory distress syndrome, with a reported failure rate ranging from 19 to 69 %. One of the possible mechanisms responsible for the unsuccessful IN-SUR-E method, requiring subsequent re-intubation and mechanical ventilation, is the inability of the preterm lung to achieve and maintain an “optimal” functional residual capacity. The importance of lung recruitment before surfactant administration has been demonstrated in animal studies showing that recruitment leads to a more homogeneous surfactant distribution within the lungs. Therefore, the aim of this study is to compare the application of a recruitment maneuver using the high-frequency oscillatory ventilation (HFOV) modality just before the surfactant administration followed by rapid extubation (INtubate-RECruit-SURfactant-Extubate: IN-REC-SUR-E) with IN-SUR-E alone in spontaneously breathing preterm infants requiring nasal continuous positive airway pressure (nCPAP) as initial respiratory support and reaching pre-defined CPAP failure criteria.

Methods/design

In this study, 206 spontaneously breathing infants born at 24⁺⁰–27⁺⁶ weeks’ gestation and failing nCPAP during the first 24 h of life, will be randomized to receive an HFOV recruitment maneuver (IN-REC-SUR-E) or no recruitment maneuver (IN-SUR-E) just prior to surfactant administration followed by prompt extubation. The primary outcome is the need for mechanical ventilation within the first 3 days of life. Infants in both groups will be considered to have reached the primary outcome when they are not extubated within 30 min after surfactant administration or when they meet the nCPAP failure criteria after extubation.

Discussion

From all available data no definitive evidence exists about a positive effect of recruitment before surfactant instillation, but a rationale exists for testing the following hypothesis: a lung recruitment maneuver performed with a step-by-step Continuous Distending Pressure increase during High-Frequency Oscillatory Ventilation (and not with a sustained inflation) could have a positive effects in terms of improved surfactant distribution and consequent its major efficacy in preterm newborns with respiratory distress syndrome. This represents our challenge.

Trial registration

ClinicalTrials.gov identifier: NCT02482766. Registered on 1 June 2015.

"EEG abnormalities" may represent a confounding factor in celiac disease: A 4-year follow-up family report

OBJECTIVE

The occurrence of celiac disease (CD), electroencephalographic (EEG) abnormalities (with "subtle" seizures or even without any clinical seizures), and neurological disorders has been reported since the 1980s, though there has been no definitive consensus about the possible causal relationship. This topic is further complicated by the occurrence in infancy of 'clinical-EEG pictures' called 'benign epilepsy of infancy'.

METHODS AND RESULTS

Here, we report a 4-year follow-up on two siblings with newly diagnosed biopsy-proven celiac disease showing EEG abnormalities not responsive to a gluten-free diet.

CONCLUSIONS

This family report indicates that in patients with neurologically asymptomatic CD and EEG abnormalities, it is advisable to make a differential diagnosis between EEG abnormalities associated with CD and an incidental association with cortical hyperexcitability, with "subtle" seizures or even without any clinical seizures.

PRACTICE IMPLICATIONS

A long follow-up may sometimes be required, as it was in the family described here, to clarify the etiopathogenetic and therapeutic relationships between clinical and EEG features in CD.

Pulmonary and extrapulmonary acute respiratory distress syndrome are different

Acute respiratory distress syndrome (ARDS) can be derived from two pathogenetic pathways: a direct insult on lung cells (pulmonary ARDS (ARDSp)) or indirectly (extrapulmonary ARDS (ARDSexp)). This review reports and discusses differences in biochemical activation, histology, morphological aspects, respiratory mechanics and response to different ventilatory strategies between ARDSp and ARDSexp. In ARDSp the direct insult primarily affects the alveolar epithelium with a local alveolar inflammatory response while in ARDSexp the indirect insult affects the vascular endothelium by inflammatory mediators through the bloodstream. Radiological pattern in ARDSp is characterised by a prevalent alveolar consolidation while the ARDSexp by a prevalent ground-glass opacification. In ARDSp the lung elastance, while in ARDSexp the chest wall and intra-abdominal chest elastance are increased. The effects of positive end-expiratory pressure, recruitment manoeuvres and prone position are clearly greater in ARDSexp. Although these two types of acute respiratory distress syndrome have different pathogenic pathways, morphological aspects, respiratory mechanics, and different response to ventilatory strategies, at the present, is still not clear, if this distinction can really ameliorate the outcome.

[A rationale basis for airways conditioning: too wet or not too wet? ]

Medical gases conditioning during mechanical invasive ventilation is nowadays a problem. In fact, in spite of conditioning guidelines, absolute humidity (AH) into 25-35 mg/l, clinical evaluation of the optimal level of airway humidification has not yet been established with certainty. Physiologically, during spontaneous respiration the airway hydric balance, inspiratory AH expiratory AH, is negative of 27 mg/l about. Usually the patients on mechanical ventilation have an expiratory AH of 32-33 mg/l. An overhumidification of inspired gases, positive airway hydric balance, gives anatomic-physiological alterations of airways and lung parenchyma. During invasive mechanical ventilation, the practice of active hot humidifiers has a positive or level airway hydric balance. We think that inspired AH must be equal to expired AH to maintain an airway hydric balance at least level. At last, the temperature of inspired gases, with active hot humidifiers, shouldn't exceed 32-34 degrees C.