A quality appraisal using the AGREE II instrument of endotracheal tube suction guidelines in neonatal intensive care units.

BACKGROUND: Endotracheal tube (ETT) suction is among the most common procedures performed in neonatal intensive care units (NICUs). Although necessary, it is associated with significant risks. To mitigate these risks, clinical practice guidelines are developed to provide evidence-based recommendations. OBJECTIVE: The aim of the study was to appraise the quality of neonatal ETT suction guidelines from all NICUs in Australia and New Zealand. METHODS: All level III NICUs in Australia and New Zealand were invited to participate. Three researchers graded the methodological quality of the received guidelines using the AGREE II instrument. Item and domain scores were calculated by scaling as a percentage of the total possible score out of 100%. A threshold score of <50% is considered to be of limited potential use. RESULTS: Twenty-three (79.31%) clinical practice guidelines were received from 29 invited facilities. The scaled results of the AGREE II domains were as follows: Scope and Purpose, mean = 73%, 95% confidence interval (CI) = 63-83%; Stakeholder Involvement, mean = 23%, 95% CI = 15-31%; Rigour of Development, mean = 17%, 95% CI = 12-21%; Clarity of Presentation, mean = 63%, 95% CI = 56-70%; Applicability, mean = 5%, 95% CI = 20-30%; and Editorial Independence, mean = 50%, 95% CI = 50-50%. Overall assessment indicated low methodological quality (31%; 22-39%), with only five clinical practice guidelines scoring >50%, suggesting that they could be recommended for use with modifications. The remaining 18 could not be recommended for use. CONCLUSIONS: Neonatal ETT suction guidelines are of a low methodological quality. All guidelines poorly incorporated latest evidence in guideline development. This appraisal highlights the need to improve the quality of neonatal ETT suction guidelines to promote optimal patient care.

Strategies for the discontinuation of humidified high flow nasal cannula (HHFNC) in preterm infants.

BACKGROUND: Humidified high flow nasal cannula (HHFNC) delivers humidified gas at increased flow rates via binasal prongs and is becoming widely accepted as a method of non-invasive respiratory support for preterm infants. While indications for the use of (HHFNC) and its associated risks and benefits are being investigated, the best strategy for the discontinuation of HHFNC remains unknown. At what point an infant is considered stable enough to attempt to start withdrawing their HHFNC is not known. The criteria for a failed attempt at HHFNC discontinuation is also unclear. OBJECTIVES: To determine the risks and benefits of different strategies used for the discontinuation of HHFNC in preterm infants. SEARCH METHODS: We searched the Cochrane Neonatal Review Group Specialized Register, PubMed (1966 to March 2015), CINAHL (1982 to March 2015), EMBASE (1980 to March 2015), and the Cochrane Central Register of Controlled Trials (CENTRAL). Also, we checked previous reviews, including cross references. We searched for following web sites for ongoing trials: ClinicalTrials.gov and controlled-trials.com. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs in which either individual newborn infants or clusters of infants (such as separate neonatal units) were randomised to different HHFNC withdrawal strategies (from the first time they come off HHFNC and any subsequent weaning, or withdrawal attempt, or both). DATA COLLECTION AND ANALYSIS: We used standard methods of Cochrane and the Cochrane Neonatal Review Group. MAIN RESULTS: We identified no eligible studies examining the best strategy to wean or withdraw HHFNC once started as respiratory support in preterm infants AUTHORS' CONCLUSIONS: There is currently no evidence available to suggest the best strategy for weaning and withdrawing HHFNC as a respiratory support in preterm infants. Research is required into the best strategy for withdrawal of HHFNC and to which subgroups this applies. Clear criteria for the definition of stability prior to attempting to withdraw HHFNC needs to be established. Furthermore, clear definitions are needed as to what constitutes failure of HHFNC.

High-flow nasal cannula therapy for respiratory support in children.

BACKGROUND: Respiratory support is a central component of the management of critically ill children. It can be delivered invasively via an endotracheal tube or non-invasively via face mask, nasal mask, nasal cannula or oxygen hood/tent. Invasive ventilation can be damaging to the lungs, and the tendency to use non-invasive forms is growing. However, non-invasive delivery is often poorly tolerated by children. High-flow nasal cannula (HFNC) oxygen delivery is a relatively new therapy that shows the potential to reduce the need for intubation and be better tolerated by children than other non-invasive forms of support. HFNC therapy differs from other non-invasive forms of treatment in that it delivers heated, humidified and blended air/oxygen via nasal cannula at rates > 2 L/kg/min. This allows the user to deliver high concentrations of oxygen and to potentially deliver continuous distending pressure; this treatment often is better tolerated by the child. OBJECTIVES: To determine whether HFNC therapy is more effective than other forms of non-invasive therapy in paediatric patients who require respiratory support. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 4); MEDLINE via PubMed (January 1966 to April 2013); EMBASE (January 1980 to April 2013); CINAHL (1982 to April 2013); and LILACS (1982 to April 2013). Abstracts from conference proceedings, theses and dissertations and bibliographical references to relevant studies were also searched. We applied no restriction on language. SELECTION CRITERIA: We planned to included randomized controlled trials (RCTs) and quas-randomized trials comparing HFNC therapy with other forms of non-invasive respiratory support for children. Non-invasive support encompassed cot, hood or tent oxygen; low-flow nasal cannulae (flow rates ≤ 2 L/min); and continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP) delivered via facial or nasal mask/cannula. Treatment failure was defined by the need for additional respiratory support. We excluded children with a diagnosis of bronchiolitis. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed all studies for selection and data extraction. We used standard methodological procedures expected by The Cochrane Collaboration. MAIN RESULTS: Our search yielded 922 records. A total of 109 relevant records were retrieved with reference to our search criteria. After duplicates and irrelevant studies were removed, 69 studies were further scrutinized. Of these, 11 studies involved children. No study matched our inclusion criteria. AUTHORS' CONCLUSIONS: Based on the results of this review, no evidence is available to allow determination of the safety or effectiveness of HFNC as a form of respiratory support in children.

Physiologic effect of high-flow nasal cannula in infants with bronchiolitis.

OBJECTIVE: To assess the effect of delivering high-flow nasal cannula flow on end-expiratory lung volume, continuous distending pressure, and regional ventilation distribution in infants less than 12 months old with bronchiolitis. DESIGN: Prospective observational clinical study. SETTING: Nineteen bed medical and surgical PICU. PATIENTS: Thirteen infants with bronchiolitis on high-flow nasal therapy. INTERVENTIONS: The study infants were measured on a flow rate applied at 2 and 8 L/min through the high-flow nasal cannula system. MEASUREMENTS AND RESULTS: Ventilation distribution was measured with regional electrical impedance amplitudes and end-expiratory lung volume using electrical impedance tomography. Changes in continuous distending pressure were measured from the esophagus via the nasogastric tube. Physiological variables were also recorded. High-flow nasal cannula delivered at 8 L/min resulted in significant increases in global and anterior end-expiratory lung volume (p < 0.01) and improvements in the physiological variables of respiratory rate, SpO2, and FIO2 when compared with flows of 2 L/min. CONCLUSION: In infants with bronchiolitis, high-flow nasal cannula oxygen/air delivered at 8 L/min resulted in increases in end-expiratory lung volume and improved respiratory rate, FIO2, and SpO2.

Lung recruitment and endotracheal suction in ventilated preterm infants measured with electrical impedance tomography.

AIMS: Although suctioning is a standard airway maintenance procedure, there are significant associated risks, such as loss of lung volume due to high negative suction pressures. This study aims to assess the extent and duration of change in end-expiratory level (EEL) resulting from endotracheal tube (ETT) suction and to examine the relationship between EEL and regional lung ventilation in ventilated preterm infants with respiratory distress syndrome. METHODS: A prospective observational clinical study of the effect of ETT suction on 20 non-muscle-relaxed preterm infants with respiratory distress syndrome (RDS) on conventional mechanical ventilation was conducted in a neonatal intensive care unit. Ventilation distribution was measured with regional impedance amplitudes and EEL using electrical impedance tomography. RESULTS: ETT suction resulted in a significant increase in EEL post-suction (P < 0.01). Regionally, anterior EEL decreased and posterior EEL increased post-suction, suggesting heterogeneity. Tidal volume was significantly lower in volume-guarantee ventilation compared with pressure-controlled ventilation (P = 0.04). CONCLUSIONS: ETT suction in non-muscle-relaxed and ventilated preterm infants with RDS results in significant lung volume increase that is maintained for at least 90 min. Regional differences in distribution of ventilation with ETT suction suggest that the behaviour of the lung is heterogeneous in nature.

Sensitivity and specificity of the Neonatal Visual Assessment to predict motor and cognitive outcomes in infants born very preterm.

BACKGROUND: Very preterm infants are at increased risk of neurodevelopmental impairments. The Neonatal Visual Assessment (NVA) assesses visual function and outcomes and has been used to assess early neurodevelopmental outcomes. This study aimed to compare NVA results of very preterm and term-born infants and to calculate the sensitivity and specificity of the NVA at term equivalent age (TEA) and three months corrected age (CA) to predict motor and cognitive outcomes at 12 months CA in very preterm infants. METHODS: This prospective observational cohort study recruited infants born before 31 weeks gestation and a healthy term-born control group. The NVA was assessed at TEA and three months CA, and neurodevelopmental outcomes (Bayley Scales of Infant and Toddler Development, Third Edition; Neurosensory Motor Developmental Assessment; Alberta Infant Motor Scale) were performed at 12 months CA. The sensitivity and specificity of the NVA to predict outcomes were calculated based on a previously published optimality score. RESULTS: 248 preterm (54 % male) and 46 term-born infants (48 % male) were analysed. The mean NVA scores of preterm and term-born infants were significantly different at TEA (preterm 3.1±2.1; term-born 1.2±1.7, p < 0.001). The NVA had moderate sensitivity (59-78 %) and low specificity (25-27 %) at TEA, and low sensitivity (21-28 %) and high specificity (86-87 %) at three months CA for the prediction of preterm infants' outcomes at 12 months CA. CONCLUSION: The NVA at TEA and three months CA was not a strong predictor of motor and cognitive impairments in this contemporary cohort of very preterm infants.

Effect of body position on ventilation distribution in ventilated preterm infants.

RATIONALE: Positioning is considered vital to the maintenance of good lung ventilation by optimizing oxygen transport and gas exchange in ventilated premature infants. Previous studies suggest that the prone position is advantageous; however, no data exist on regional ventilation distribution for this age group. OBJECTIVES: To investigate the effect of body position on regional ventilation distribution in ventilated and nonventilated preterm infants using electrical impedance tomography. DESIGN: Randomized crossover study design. SETTING: Neonatal ICU. PATIENTS: A total of 24 ventilated preterm infants were compared with six spontaneously breathing preterm infants. INTERVENTIONS: Random assignment of the order of the positions supine, prone, and quarter prone. MEASUREMENTS AND MAIN RESULTS: Ventilation distribution was measured with regional impedance amplitudes and global inhomogeneity indices using electrical impedance tomography. In the spontaneously breathing infants, regional impedance amplitudes were increased in the posterior compared with the anterior lung (p < 0.01) and in the right compared with the left lung (p = 0.03). No differences were found in the ventilated infants. Ventilation was more inhomogeneous in the ventilated compared with the healthy infants (p < 0.01). Assessment of temporal regional lung filling showed that the posterior lung filled earlier than the anterior lung in the spontaneously breathing infants (p < 0.02) whereas in the in the ventilated infants the right lung filled before the left lung (p < 0.01). CONCLUSIONS: In contrast to previous studies showing that ventilation is distributed to the nondependent lung in infants and children, this study shows that gravity has little effect on regional ventilation distribution.

Effect of body position on ventilation distribution in preterm infants on continuous positive airway pressure.

RATIONALE: Although continuous positive airway pressure is used extensively in neonatal intensive care units, and despite the belief that positioning is considered vital to the maintenance of good lung ventilation, no data exist on regional ventilation distribution in infants on continuous positive airway pressure ventilatory support. OBJECTIVES: To investigate the effect of body position on regional ventilation in preterm infants on continuous positive airway pressure ventilatory support using electrical impedance tomography. DESIGN: Randomized crossover study design. SETTING: Neonatal intensive care unit. PATIENTS: Twenty-four preterm infants on continuous positive airway pressure were compared to six spontaneously breathing preterm infants. INTERVENTIONS: Random assignment of the order of the positions supine, prone, and quarter prone. MEASUREMENTS AND RESULTS: Changes in global and regional lung volume were measured with electrical impedance tomography. Although there were no differences between positions, regional tidal volume was increased in the posterior compared with the anterior lung (p < .01) and in the right compared with the left lung (p < .03) in both the spontaneously breathing infants and in the infants on continuous positive airway pressure. The posterior lung filled earlier than the anterior lung in the spontaneously breathing infants (p < .02), whereas in the infants on continuous positive airway pressure the right lung filled before the left lung (p < .01). There was more ventilation inhomogeneity in the infants on continuous positive airway pressure than in the healthy infants (p < .01). CONCLUSIONS: This study presents the first results on regional ventilation distribution in preterm infants on continuous positive airway pressure using electrical impedance tomography. Gravity had little impact on regional ventilation distribution in preterm infants on continuous positive airway pressure or in spontaneously breathing infants in the supine or prone position, indicating that ventilation distribution in preterm infants is not gravity-dependent but follows an anatomical pattern. AUSTRALIA NEW ZEALAND CLINICAL TRIALS REGISTRY:: ACTRN12606000210572.

Humidified high flow nasal cannulae: current practice in Australasian nurseries, a survey.

AIM: Humidified High Flow Nasal Cannula (HHFNC) has been increasingly adopted as a new means of respiratory support throughout the world. However, evidence to support its safety and efficacy is limited. The aim of the present survey was to determine current practices regarding the usage of HHFNC by neonatologists in Australia and New Zealand. METHODS: Surveys were sent to all 167 neonatologists identified by the list of centres in the Australia and New Zealand Neonatal Network. RESULTS: A total of 157 surveys were sent to valid email addresses: 111 (71%) responded of which 105 (67%) had completed the questionnaire. HHFNC is used in 17 (63%) of neonatal intensive care units in Australia and New Zealand. It is most commonly used to reduce nasal trauma (91%) and provide continuous positive airways pressure (62%). The main perceived benefits of HHFNC were the easier application and care of the infant (86%), and improved tolerance by the baby (84%). Rain out leading to fluid instillation into the upper airway (59%) was the most common problem. CONCLUSION: This survey has provided a snapshot of the practice of HHFNC usage in Australia and New Zealand in 2010 and has revealed that HHFNC use is widespread and that clinical practices are diverse. The majority of neonatologists acknowledge that there is limited evidence to support its efficacy and safety, and would be happy to participate in clinical trials to address how best to deliver HHFNC.

Measuring the effects of airway clearance in mechanically ventilated infants and children: A systematic review.

BACKGROUND: Robust measurement tools are essential in guiding physiotherapy-delivered airway clearance techniques to ventilated infants and children. OBJECTIVE: To identify measurement tools used to evaluate effects of airway clearance techniques in ventilated infants and children and to determine the clinimetric properties of these tools. DATA SOURCES: Pubmed, CINAHL, Embase, The Cochrane Library, Physiotherapy Evidence Database and Web of Science, up to November 2020. STUDY SELECTION: Randomized and non-randomized clinical trials measuring any aspect of lung function during and/or after airway clearance techniques in mechanically ventilated infants and children from birth to sixteen years. DATA EXTRACTION AND DATA SYNTHESIS: Two independent reviewers identified tools measuring effects of airway clearance techniques including secretion clearance, respiratory mechanics, gas exchange and changes on lung imaging. Extracted data included details of the tool, airway clearance intervention being evaluated and aspects of lung function being measured. Assessment of quality and clinimetric properties, including validity, reliability and responsiveness, were evaluated for each tool using the COnsensus-based Standards for the selection of health status Measurement INstruments methodology. RESULTS: Nine measurement tools measured the effects of airway clearance techniques on secretion clearance, respiratory mechanics, gas exchange and lung imaging. Five tools reported clinimetric properties although the yield and overall quality of studies was low. Tools measured many different aspects of lung function. The CO2SMO Plus respiratory mechanics monitor reported the most clinimetric data. LIMITATIONS: Unpublished or in-progress studies were not included to ensure all data collected were peer-reviewed, therefore additional or novel tools may not have been identified. Included age ranges and definition of airway clearance techiques were kept broad to optimise study identification which may limit generalisability of results. CONCLUSION: Measurement tools used by physiotherapists to enhance airway clearance in ventilated infants and children lack high quality evidence of validity, reliability and responsiveness. Measurements gained through these tools should therefore be interpreted with careful consideration until further climimetric evidence is available. CONTRIBUTION OF PAPER.

Nasal high flow in preterm infants: A dose-finding study.

OBJECTIVE: To investigate the relationship between applied flows of nasal high flow (NHF) and physiological outcomes and work of breathing (WOB), to identify an optimal delivery flow which results in reduced WOB in preterm infants. DESIGN: A prospective observational clinical study with randomly applied NHF rates. PATIENTS AND SETTING: Preterm infants within 72 hours of commencement of NHF respiratory support. INTERVENTIONS: Infants were initially placed on 8 L/min of NHF and flows of 2, 4, and 6 L/min were then applied in random order. MEASUREMENTS AND RESULTS: WOB was measured using transcutaneous electromyography and respiratory inductance plethysmography. Physiological variables were also recorded. Measurements taken 10 minutes after each flow change were compared with 8 L/min. Sixteen infants with a median gestational age of 28 (range 24-31) weeks and postnatal age of 14 (2-55) days were included in the study. The median flow rate before the study was 6 (4-8) L/min and a fraction of inspired oxygen (FiO2 ) was 0.21 (0.21-0.26). Changes in flow resulted in changes in activity in the front diaphragm (P = .027) and intercostals (P = .034). The electrical activity of the front diaphragm at 8 L/min was significantly lower than that at 2 L/min (P = .016). Respiratory rate was lowest at 6 L/min (P = .002) and SpO2 /FiO2 was highest at 8 L/min (P < .04). CONCLUSION: In preterm infants, changes in WOB resulting from randomly applied levels of NHF can be demonstrated by measuring the electrical activity of the diaphragm and intercostal muscles with transcutaneous electromyography. In combination with physiological measurements, the similarities in electrical activity between 4, 6, and 8 L/min suggest that these three flows may be equally as effective.

Chest wall mesenchymal hamartoma in an infant: Evaluation with electrical impedance tomography.

Mesenchymal hamartoma of the chest wall is a rare benign nonneoplastic lesion of infancy arising from chondro-osseous tissue. Although its natural history suggests spontaneous regression, we describe a fatal case in a neonate with significant respiratory compromise. We explored the use of electrical impedance tomography to evaluate the dynamic impact of such space occupying lesions on a ventilated infant.

Effect of randomization of nasal high flow rate in preterm infants.

OBJECTIVE: To assess the effect of nasal high flow (NHF) cannula on end-expiratory level (EEL), continuous distending pressure (CDP) and regional ventilation distribution in preterm infants. DESIGN: A prospective observational clinical study with randomly applied NHF rates. PATIENTS AND SETTING: Preterm infants requiring continuous positive airway pressure (CPAP) respiratory support in a Neonatal Intensive Care Unit. INTERVENTIONS: Infants were measured on randomly applied flow rates at 2, 4, and 6 L/min of NHF and compared with bubble CPAP. MEASUREMENTS AND RESULTS: Regional ventilation distribution and EEL were measured using electrical impedance tomography (EIT) and respiratory inductance plethysmography (RIP) in 24 preterm infants (31.19 ± 1.17 weeks corrected age). Changes in CDP were measured from the esophagus via the nasogastric tube. Physiological variables were also recorded. There were no differences in ventilation distribution, EEL or CDP between CPAP and NHF (P > .05). However, the physiological variables of FiO2 (P = .01) and SpO2 /FiO2 (P < .01) were improved on CPAP compared with NHF. CONCLUSION: NHF applied in random order with flow rates between 2 to 6 L/min was equally as good as CPAP in maintaining EEL and ventilation distribution in stable preterm infants. Overall oxygenation was better on CPAP compared to NHF.

Chest physiotherapy for reducing respiratory morbidity in infants requiring ventilatory support.

BACKGROUND: Chest physiotherapy (CPT) has been used in many neonatal nurseries around the world to improve airway clearance and treat lung collapse; however, the evidence to support its use has been conflicting. Despite the large number of studies there is very little evidence of sufficiently good quality on which to base current practice. OBJECTIVES: To assess the effects of active CPT techniques, such as percussion and vibration followed by suction compared with suction alone, on the respiratory system in infants receiving mechanical ventilation. Additionally, differences between types of active CPT techniques were assessed. SEARCH STRATEGY: Our search included The Cochrane Library (Issue 2, 2007), MEDLINE (1966 to 2007), EMBASE (1988 to 2007), CINAHL, Science Citation Index, previous reviews including cross-references, abstracts, conference proceedings and grey literature. SELECTION CRITERIA: Trials in which ventilated newborn infants up to four weeks of age were randomly or quasi-randomly assigned to receive active CPT or suction alone. Infants receiving CPT for the extubation period were excluded. DATA COLLECTION AND ANALYSIS: Two review authors independently conducted quality assessments and data extraction for included trials. We analysed data for individual trial results using relative risk (RR) and mean difference (MD). Results are presented with 95% confidence intervals (CI). Due to insufficient data, we could not undertake meta-analysis. MAIN RESULTS: Three trials involving 106 infants were included in this review. In one trial (n = 20) CPT was no better than standard care in clearing secretions. No increase in the risk of intraventricular haemorrhage was noted. Two trials compared different types of active CPT. One trial (n = 56) showed that non-resolved atelectasis was reduced in more neonates receiving the lung squeezing technique (LST) when compared to postural drainage, percussion and vibration (PDPV) (RR 0.25; 95% CI 0.11 to 0.57). No difference in secretion clearance or in the rate of intraventricular haemorrhage or periventricular leucomalacia was demonstrated. The other trial (n = 30) showed that the use of percussion or 'cupping' resulted in an increased incidence of hypoxaemia (RR 0.53; 95% CI 0.28 to 0.99) and increased oxygen requirements (MD -9.68; 95% CI -14.16 to -5.20) when compared with contact heel percussion. There was insufficient information to adequately assess important short and longer-term outcomes, including adverse effects. AUTHORS' CONCLUSIONS: The results of this review do not provide sufficient evidence on which to base clinical practice. There is a need for larger randomised controlled trials to address these issues.