Neurally adjusted ventilatory assist compared to other forms of triggered ventilation for neonatal respiratory support.

BACKGROUND: Effective synchronisation of infant respiratory effort with mechanical ventilation may allow adequate gas exchange to occur at lower peak airway pressures, potentially reducing barotrauma and volutrauma and development of air leaks and bronchopulmonary dysplasia. During neurally adjusted ventilatory assist ventilation (NAVA), respiratory support is initiated upon detection of an electrical signal from the diaphragm muscle, and pressure is provided in proportion to and synchronous with electrical activity of the diaphragm (EADi). Compared to other modes of triggered ventilation, this may provide advantages in improving synchrony. OBJECTIVES: Primary• To determine whether NAVA, when used as a primary or rescue mode of ventilation, results in reduced rates of bronchopulmonary dysplasia (BPD) or death among term and preterm newborn infants compared to other forms of triggered ventilation• To assess the safety of NAVA by determining whether it leads to greater risk of intraventricular haemorrhage (IVH), periventricular leukomalacia, or air leaks when compared to other forms of triggered ventilation Secondary• To determine whether benefits of NAVA differ by gestational age (term or preterm)• To determine whether outcomes of cross-over trials performed during the first two weeks of life include peak pressure requirements, episodes of hypocarbia or hypercarbia, oxygenation index, and the work of breathing SEARCH METHODS: We performed searches of the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cohrane Library; MEDLINE via Ovid SP (January 1966 to March 2017); Embase via Ovid SP (January 1980 to March 2017); the Cumulative Index to Nursing and Allied Health Literature (CINAHL) via EBSCO host (1982 to March 2017); and the Web of Science (1985 to 2017). We searched abstracts from annual meetings of the Pediatric Academic Societies (PAS) (2000 to 2016); meetings of the European Society of Pediatric Research (published in Pediatric Research); and meetings of the Perinatal Society of Australia and New Zealand (PSANZ) (2005 to 2016). We also searched clinical trials databases to March 2017. SELECTION CRITERIA: We included randomised and quasi-randomised clinical trials including cross-over trials comparing NAVA with other modes of triggered ventilation (assist control ventilation (ACV),synchronous intermittent mandatory ventilation plus pressure support (SIMV ± PS), pressure support ventilation (PSV), or proportional assist ventilation (PAV)) used in neonates. DATA COLLECTION AND ANALYSIS: Primary outcomes of interest from randomised controlled trials were all-cause mortality, bronchopulmonary dysplasia (BPD; defined as oxygen requirement at 28 days), and a combined outcome of all-cause mortality or BPD. Secondary outcomes were duration of mechanical ventilation, incidence of air leak, incidence of IVH or periventricular leukomalacia, and survival with an oxygen requirement at 36 weeks' postmenstrual age.Outcomes of interest from cross-over trials were maximum fraction of inspired oxygen, mean peak inspiratory pressure, episodes of hypocarbia, and episodes of hypercarbia measured across the time period of each arm of the cross-over. We planned to assess work of breathing; oxygenation index, and thoraco-abdominal asynchrony at the end of the time period of each arm of the cross-over study. MAIN RESULTS: We included one randomised controlled study comparing NAVA versus patient-triggered time-cycled pressure-limited ventilation. This study found no significant difference in duration of mechanical ventilation, nor in rates of BPD, pneumothorax, or IVH. AUTHORS' CONCLUSIONS: Risks and benefits of NAVA compared to other forms of ventilation for neonates are uncertain. Well-designed trials are required to evaluate this new form of triggered ventilation.

Synchronized mechanical ventilation for respiratory support in newborn infants.

BACKGROUND: During synchronised mechanical ventilation, positive airway pressure and spontaneous inspiration coincide. If synchronous ventilation is provoked, adequate gas exchange should be achieved at lower peak airway pressures, potentially reducing baro/volutrauma, air leak and bronchopulmonary dysplasia. Synchronous ventilation can potentially be achieved by manipulation of rate and inspiratory time during conventional ventilation and employment of patient-triggered ventilation. OBJECTIVES: To compare the efficacy of:(i) synchronised mechanical ventilation, delivered as high-frequency positive pressure ventilation (HFPPV) or patient-triggered ventilation (assist control ventilation (ACV) and synchronous intermittent mandatory ventilation (SIMV)), with conventional ventilation or high-frequency oscillation (HFO);(ii) different types of triggered ventilation (ACV, SIMV, pressure-regulated volume control ventilation (PRVCV), SIMV with pressure support (PS) and pressure support ventilation (PSV)). SEARCH METHODS: We used the standard search strategy of the Cochrane Neonatal Review group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 5), MEDLINE via PubMed (1966 to June 5 2016), EMBASE (1980 to June 5 2016), and CINAHL (1982 to June 5 2016). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. SELECTION CRITERIA: Randomised or quasi-randomised clinical trials comparing synchronised ventilation delivered as HFPPV to CMV, or ACV/SIMV to CMV or HFO in neonates. Randomised trials comparing different triggered ventilation modes (ACV, SIMV, SIMV plus PS, PRVCV and PSV) in neonates. DATA COLLECTION AND ANALYSIS: Data were collected regarding clinical outcomes including mortality, air leaks (pneumothorax or pulmonary interstitial emphysema (PIE)), severe intraventricular haemorrhage (grades 3 and 4), bronchopulmonary dysplasia (BPD) (oxygen dependency beyond 28 days), moderate/severe BPD (oxygen/respiratory support dependency beyond 36 weeks' postmenstrual age (PMA) and duration of weaning/ventilation.Eight comparisons were made: (i) HFPPV versus CMV; (ii) ACV/SIMV versus CMV; (iii) SIMV or SIMV + PS versus HFO; iv) ACV versus SIMV; (v) SIMV plus PS versus SIMV; vi) SIMV versus PRVCV; vii) SIMV vs PSV; viii) ACV versus PSV. Data analysis was conducted using relative risk for categorical outcomes, mean difference for outcomes measured on a continuous scale. MAIN RESULTS: Twenty-two studies are included in this review. The meta-analysis demonstrates that HFPPV compared to CMV was associated with a reduction in the risk of air leak (typical relative risk (RR) for pneumothorax was 0.69, 95% confidence interval (CI) 0.51 to 0.93). ACV/SIMV compared to CMV was associated with a shorter duration of ventilation (mean difference (MD) -38.3 hours, 95% CI -53.90 to -22.69). SIMV or SIMV + PS was associated with a greater risk of moderate/severe BPD compared to HFO (RR 1.33, 95% CI 1.07 to 1.65) and a longer duration of mechanical ventilation compared to HFO (MD 1.89 days, 95% CI 1.04 to 2.74).ACV compared to SIMV was associated with a trend to a shorter duration of weaning (MD -42.38 hours, 95% CI -94.35 to 9.60). Neither HFPPV nor triggered ventilation was associated with a significant reduction in the incidence of BPD. There was a non-significant trend towards a lower mortality rate using HFPPV versus CMV and a non-significant trend towards a higher mortality rate using triggered ventilation versus CMV. No disadvantage of HFPPV or triggered ventilation was noted regarding other outcomes. AUTHORS' CONCLUSIONS: Compared to conventional ventilation, benefit is demonstrated for both HFPPV and triggered ventilation with regard to a reduction in air leak and a shorter duration of ventilation, respectively. In none of the trials was complex respiratory monitoring undertaken and thus it is not possible to conclude that the mechanism of producing those benefits is by provocation of synchronised ventilation. Triggered ventilation in the form of SIMV ± PS resulted in a greater risk of BPD and duration of ventilation compared to HFO. Optimisation of trigger and ventilator design with respect to respiratory diagnosis is encouraged before embarking on further trials. It is essential that newer forms of triggered ventilation are tested in randomised trials that are adequately powered to assess long-term outcomes before they are incorporated into routine clinical practice.

Synchronized mechanical ventilation for respiratory support in newborn infants.

BACKGROUND: During synchronised mechanical ventilation, positive airway pressure and spontaneous inspiration coincide. If synchronous ventilation is provoked, adequate gas exchange should be achieved at lower peak airway pressures, potentially reducing baro/volutrauma, air leak and bronchopulmonary dysplasia. Synchronous ventilation can potentially be achieved by manipulation of rate and inspiratory time during conventional ventilation and employment of patient-triggered ventilation. OBJECTIVES: To compare the efficacy of:(i) synchronised mechanical ventilation, delivered as high-frequency positive pressure ventilation (HFPPV) or patient-triggered ventilation (assist control ventilation (ACV) and synchronous intermittent mandatory ventilation (SIMV)), with conventional ventilation or high-frequency oscillation (HFO);(ii) different types of triggered ventilation (ACV, SIMV, pressure-regulated volume control ventilation (PRVCV), SIMV with pressure support (PS) and pressure support ventilation (PSV)). SEARCH METHODS: We used the standard search strategy of the Cochrane Neonatal Review group to search the Cochrane Central Register of Controlled Trials (CENTRAL 2016, Issue 5), MEDLINE via PubMed (1966 to June 5 2016), EMBASE (1980 to June 5 2016), and CINAHL (1982 to June 5 2016). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. SELECTION CRITERIA: Randomised or quasi-randomised clinical trials comparing synchronised ventilation delivered as HFPPV to CMV, or ACV/SIMV to CMV or HFO in neonates. Randomised trials comparing different triggered ventilation modes (ACV, SIMV, SIMV plus PS, PRVCV and PSV) in neonates. DATA COLLECTION AND ANALYSIS: Data were collected regarding clinical outcomes including mortality, air leaks (pneumothorax or pulmonary interstitial emphysema (PIE)), severe intraventricular haemorrhage (grades 3 and 4), bronchopulmonary dysplasia (BPD) (oxygen dependency beyond 28 days), moderate/severe BPD (oxygen/respiratory support dependency beyond 36 weeks' postmenstrual age (PMA) and duration of weaning/ventilation.Eight comparisons were made: (i) HFPPV versus CMV; (ii) ACV/SIMV versus CMV; (iii) SIMV or SIMV + PS versus HFO; iv) ACV versus SIMV; (v) SIMV plus PS versus SIMV; vi) SIMV versus PRVCV; vii) SIMV vs PSV; viii) ACV versus PSV. Data analysis was conducted using relative risk for categorical outcomes, mean difference for outcomes measured on a continuous scale. MAIN RESULTS: Twenty-two studies are included in this review. The meta-analysis demonstrates that HFPPV compared to CMV was associated with a reduction in the risk of air leak (typical relative risk (RR) for pneumothorax was 0.69, 95% confidence interval (CI) 0.51 to 0.93). ACV/SIMV compared to CMV was associated with a shorter duration of ventilation (mean difference (MD) -38.3 hours, 95% CI -53.90 to -22.69). SIMV or SIMV + PS was associated with a greater risk of moderate/severe BPD compared to HFO (RR 1.33, 95% CI 1.07 to 1.65) and a longer duration of mechanical ventilation compared to HFO (MD 1.89 days, 95% CI 1.04 to 2.74).ACV compared to SIMV was associated with a trend to a shorter duration of weaning (MD -42.38 hours, 95% CI -94.35 to 9.60). Neither HFPPV nor triggered ventilation was associated with a significant reduction in the incidence of BPD. There was a non-significant trend towards a lower mortality rate using HFPPV versus CMV and a non-significant trend towards a higher mortality rate using triggered ventilation versus CMV. No disadvantage of HFPPV or triggered ventilation was noted regarding other outcomes. AUTHORS' CONCLUSIONS: Compared to conventional ventilation, benefit is demonstrated for both HFPPV and triggered ventilation with regard to a reduction in air leak and a shorter duration of ventilation, respectively. In none of the trials was complex respiratory monitoring undertaken and thus it is not possible to conclude that the mechanism of producing those benefits is by provocation of synchronised ventilation. Triggered ventilation in the form of SIMV ± PS resulted in a greater risk of BPD and duration of ventilation compared to HFO. Optimisation of trigger and ventilator design with respect to respiratory diagnosis is encouraged before embarking on further trials. It is essential that newer forms of triggered ventilation are tested in randomised trials that are adequately powered to assess long-term outcomes before they are incorporated into routine clinical practice.

Conservative management of Gradenigo's syndrome in a child.

Gradenigo's syndrome, the triad of suppurative otitis media, abducens nerve palsy and pain in the ophthalmic division of the trigeminal nerve, remains a rare complication of otitis media. A case in a paediatric patient is described, successfully managed conservatively. There is little evidence to support increased use of antibiotics in acute otitis media to prevent this complication.