The Diaphragmatic Initiated Ventilatory Assist (DIVA) trial: study protocol for a randomized controlled trial comparing rates of extubation failure in extremely premature infants undergoing extubation to non-invasive neurally adjusted ventilatory assist versus non-synchronized nasal intermittent positive pressure ventilation

BACKGROUND

Invasive mechanical ventilation contributes to bronchopulmonary dysplasia (BPD), the most common complication of prematurity and the leading respiratory cause of childhood morbidity. Non-invasive ventilation (NIV) may limit invasive ventilation exposure and can be either synchronized or non-synchronized (NS). Pooled data suggest synchronized forms may be superior. Non-invasive neurally adjusted ventilatory assist (NIV-NAVA) delivers NIV synchronized to the neural signal for breathing, which is detected with a specialized catheter. The DIVA (Diaphragmatic Initiated Ventilatory Assist) trial aims to determine in infants born 240/7-276/7 weeks' gestation undergoing extubation whether NIV-NAVA compared to non-synchronized nasal intermittent positive pressure ventilation (NS-NIPPV) reduces the incidence of extubation failure within 5 days of extubation.

METHODS

This is a prospective, unblinded, pragmatic, multicenter phase III randomized clinical trial. Inclusion criteria are preterm infants 24-276/7 weeks gestational age who were intubated within the first 7 days of life for at least 12 h and are undergoing extubation in the first 28 postnatal days. All sites will enter an initial run-in phase, where all infants are allocated to NIV-NAVA, and an independent technical committee assesses site performance. Subsequently, all enrolled infants are randomized to NIV-NAVA or NS-NIPPV at extubation. The primary outcome is extubation failure within 5 days of extubation, defined as any of the following: (1) rise in FiO2 at least 20% from pre-extubation for > 2 h, (2) pH ≤ 7.20 or pCO2 ≥ 70 mmHg; (3) > 1 apnea requiring positive pressure ventilation (PPV) or ≥ 6 apneas requiring stimulation within 6 h; (4) emergent intubation for cardiovascular instability or surgery. Our sample size of 478 provides 90% power to detect a 15% absolute reduction in the primary outcome. Enrolled infants will be followed for safety and secondary outcomes through 36 weeks' postmenstrual age, discharge, death, or transfer.

DISCUSSION

The DIVA trial is the first large multicenter trial designed to assess the impact of NIV-NAVA on relevant clinical outcomes for preterm infants. The DIVA trial design incorporates input from clinical NAVA experts and includes innovative features, such as a run-in phase, to ensure consistent technical performance across sites.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov , trial identifier NCT05446272 , registered July 6, 2022.

High-flow nasal cannula (HFNC) vs continuous positive airway pressure (CPAP) vs nasal intermittent positive pressure ventilation as primary respiratory support in infants of ≥ 32 weeks gestational age (GA): study protocol for a three-arm multi-center randomized controlled trial

BACKGROUND

Health problems in neonates with gestational age (GA) ≥ 32 weeks remain a major medical concern. Respiratory distress (RD) is one of the common reasons for admission of neonates with GA ≥ 32 weeks. Noninvasive ventilation (NIV) represents a crucial approach to treat RD, and currently, the most used NIV modes in neonatal intensive care unit include high-flow nasal cannula (HFNC), continuous positive airway pressure (CPAP), and nasal intermittent positive pressure ventilation. Although extensive evidence supports the use of NIPPV in neonates with a GA < 32 weeks, limited data exist regarding its effectiveness in neonates with GA ≥ 32 weeks. Therefore, the aim of this study is to compare the clinical efficacy of HFNC, CPAP, and NIPPV as primary NIV in neonates with GA ≥ 32 weeks who experience RD.

METHODS

This trial is designed as an assessor-blinded, three-arm, multi-center, parallel, randomized controlled trial, conducted in neonates ≥ 32 weeks' GA requiring primary NIV in the first 24 h of life. The neonates will be randomly assigned to one of three groups: HFNC, CPAP or NIPPV group. The effectiveness, safety and comfort of NIV will be evaluated. The primary outcome is the occurrence of treatment failure within 72 h after enrollment. Secondary outcomes include death before discharge, surfactant treatment within 72 h after randomization, duration of both noninvasive and invasive mechanical ventilation, duration of oxygen therapy, bronchopulmonary dysplasia, time to achieve full enteral nutrition, necrotizing enterocolitis, duration of admission, cost of admission, air leak syndrome, nasal trauma, and comfort score.

DISCUSSION

Currently, there is a paucity of data regarding the utilization of NIPPV in neonates with GA ≥ 32 weeks. This study will provide clinical evidence for the development of respiratory treatment strategies in neonates at GA ≥ 32 weeks with RD, with the aim of minimizing the incidence of tracheal intubation and reducing the complications associated with NIV.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR2300069192. Registered on March 9, 2023, https://www.chictr.org.cn/showproj.html?proj=171491 .

Nasal intermittent positive pressure ventilation (NIPPV) versus nasal continuous positive airway pressure (NCPAP) for preterm neonates after extubation

BACKGROUND

Nasal continuous positive airway pressure (NCPAP) is a useful method for providing respiratory support after extubation. Nasal intermittent positive pressure ventilation (NIPPV) can augment NCPAP by delivering ventilator breaths via nasal prongs.

OBJECTIVES

Primary objective To determine the effects of management with NIPPV versus NCPAP on the need for additional ventilatory support in preterm infants whose endotracheal tube was removed after a period of intermittent positive pressure ventilation. Secondary objectives To compare rates of abdominal distension, gastrointestinal perforation, necrotising enterocolitis, chronic lung disease, pulmonary air leak, mortality, duration of hospitalisation, rates of apnoea and neurodevelopmental status at 18 to 24 months for NIPPV and NCPAP. To compare the effect of NIPPV versus NCPAP delivered via ventilators versus bilevel devices, and assess the effects of the synchronisation of ventilation, and the strength of interventions in different economic settings.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was January 2023.

SELECTION CRITERIA

We included randomised and quasi-randomised trials of ventilated preterm infants (less than 37 weeks' gestational age (GA)) ready for extubation to non-invasive respiratory support. Interventions were NIPPV and NCPAP.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcome was 1. respiratory failure. Our secondary outcomes were 2. endotracheal reintubation, 3. abdominal distension, 4. gastrointestinal perforation, 5. necrotising enterocolitis (NEC), 6. chronic lung disease, 7. pulmonary air leak, 8. mortality, 9. hospitalisation, 10. apnoea and bradycardia, and 11. neurodevelopmental status. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included 19 trials (2738 infants). Compared to NCPAP, NIPPV likely reduces the risk of respiratory failure postextubation (risk ratio (RR) 0.75, 95% confidence interval (CI) 0.67 to 0.84; number needed to treat for an additional beneficial outcome (NNTB) 11, 95% CI 8 to 17; 19 trials, 2738 infants; moderate-certainty evidence) and endotracheal reintubation (RR 0.78, 95% CI 0.70 to 0.87; NNTB 12, 95% CI 9 to 25; 17 trials, 2608 infants, moderate-certainty evidence), and may reduce pulmonary air leaks (RR 0.57, 95% CI 0.37 to 0.87; NNTB 50, 95% CI 33 to infinite; 13 trials, 2404 infants; low-certainty evidence). NIPPV likely results in little to no difference in gastrointestinal perforation (RR 0.89, 95% CI 0.58 to 1.38; 8 trials, 1478 infants, low-certainty evidence), NEC (RR 0.86, 95% CI 0.65 to 1.15; 10 trials, 2069 infants; moderate-certainty evidence), chronic lung disease defined as oxygen requirement at 36 weeks (RR 0.93, 95% CI 0.84 to 1.05; 9 trials, 2001 infants; moderate-certainty evidence) and mortality prior to discharge (RR 0.81, 95% CI 0.61 to 1.07; 11 trials, 2258 infants; low-certainty evidence). When considering subgroup analysis, ventilator-generated NIPPV likely reduces respiratory failure postextubation (RR 0.49, 95% CI 0.40 to 0.62; 1057 infants; I2 = 47%; moderate-certainty evidence), while bilevel devices (RR 0.95, 95% CI 0.77 to 1.17; 716 infants) or a mix of both ventilator-generated and bilevel devices likely results in little to no difference (RR 0.87, 95% CI 0.73 to 1.02; 965 infants).

AUTHORS' CONCLUSIONS

NIPPV likely reduces the incidence of extubation failure and the need for reintubation within 48 hours to one-week postextubation more effectively than NCPAP in very preterm infants (GA 28 weeks and above). There is a paucity of data for infants less than 28 weeks' gestation. Pulmonary air leaks were also potentially reduced in the NIPPV group. However, it has no effect on other clinically relevant outcomes such as gastrointestinal perforation, NEC, chronic lung disease or mortality. Ventilator-generated NIPPV appears superior to bilevel devices in reducing the incidence of respiratory failure postextubation failure and need for reintubation. Synchronisation used to deliver NIPPV may be important; however, data are insufficient to support strong conclusions. Future trials should enrol a sufficient number of infants, particularly those less than 28 weeks' GA, to detect differences in death or chronic lung disease and should compare different categories of devices, establish the impact of synchronisation of NIPPV on safety and efficacy of the technique as well as the best combination of settings for NIPPV (rate, peak pressure and positive end-expiratory). Trials should strive to match the mean airway pressure between the intervention groups to allow a better comparison. Neurally adjusted ventilatory assist needs further assessment with properly powered randomised trials.

Early nasal intermittent positive pressure ventilation (NIPPV) versus early nasal continuous positive airway pressure (NCPAP) for preterm infants

BACKGROUND

Nasal continuous positive airway pressure (NCPAP) is a strategy to maintain positive airway pressure throughout the respiratory cycle through the application of a bias flow of respiratory gas to an apparatus attached to the nose. Early treatment with NCPAP is associated with decreased risk of mechanical ventilation exposure and might reduce chronic lung disease. Nasal intermittent positive pressure ventilation (NIPPV) is a form of noninvasive ventilation delivered through the same nasal interface during which patients are exposed to short inflations, along with background end-expiratory pressure.

OBJECTIVES

To examine the risks and benefits of early (within the first six hours after birth) NIPPV versus early NCPAP for preterm infants at risk of or with respiratory distress syndrome (RDS). Primary endpoints are respiratory failure and the need for intubated ventilatory support during the first week of life. Secondary endpoints include the incidence of mortality, chronic lung disease (CLD) (oxygen therapy at 36 weeks' postmenstrual age), pneumothorax, duration of respiratory support, duration of oxygen therapy, and intraventricular hemorrhage (IVH).

SEARCH METHODS

Searches were conducted in January 2023 in CENTRAL, MEDLINE, Embase, Web of Science, and Dissertation Abstracts. The reference lists of related systematic reviews and of studies selected for inclusion were also searched.

SELECTION CRITERIA

We considered all randomized and quasi-randomized controlled trials. Eligible studies compared NIPPV versus NCPAP treatment, starting within six hours after birth in preterm infants (< 37 weeks' gestational age (GA)).

DATA COLLECTION AND ANALYSIS

We collected and analyzed data using the recommendations of the Cochrane Neonatal Review Group.

MAIN RESULTS

We included 17 trials, enrolling 1958 infants in this review. NIPPV likely reduces the rate of respiratory failure (risk ratio (RR) 0.65, 95% confidence interval (CI) 0.54 to 0.78; risk difference (RD) -0.08, 95% CI -0.12 to -0.05; 17 RCTs, 1958 infants; moderate-certainty evidence) and needing endotracheal tube ventilation (RR 0.67, 95% CI 0.56 to 0.81; RD -0.07, 95% CI -0.11 to -0.04; 16 RCTs; 1848 infants; moderate-certainty evidence) amongst infants treated with early NIPPV compared with early NCPAP. The meta-analysis demonstrated that NIPPV may reduce the risk of developing CLD compared to CPAP (RR 0.70, 95% CI 0.52 to 0.92; 12 RCTs, 1284 infants; low-certainty evidence) slightly. NIPPV may result in little to no difference in mortality (RR 0.82, 95% CI 0.62 to 1.10; 17 RCTs; 1958 infants; I2 of 0%; low-certainty evidence), the incidence of pneumothorax (RR 0.92, 95% CI 0.60 to 1.41; 16 RCTs; 1674 infants; I2 of 0%; low-certainty evidence), and rates of severe IVH (RR 0.98, 95% CI 0.53 to 1.79; 8 RCTs; 977 infants; I2 of 0%; low-certainty evidence).

AUTHORS' CONCLUSIONS

When applied within six hours after birth, NIPPV likely reduces the risk of respiratory failure and the need for intubation and endotracheal tube ventilation in very preterm infants (GA 28 weeks and above) with respiratory distress syndrome or at risk for RDS. It may also decrease the rate of CLD slightly. However, most trials enrolled infants with a gestational age of approximately 28 to 32 weeks with an overall mean gestational age of around 30 weeks. As such, the results of this review may not apply to extremely preterm infants that are most at risk of needing mechanical ventilation or developing CLD. Additional studies are needed to confirm these results and to assess the safety of NIPPV compared with NCPAP alone in a larger patient population.

Sustained Inflation Versus Intermittent Positive Pressure Ventilation for Preterm Infants at Birth: Respiratory Function and Vital Sign Measurements

OBJECTIVE

To characterize respiratory function monitor (RFM) measurements of sustained inflations and intermittent positive pressure ventilation (IPPV) delivered noninvasively to infants in the Sustained Aeration of Infant Lungs (SAIL) trial and to compare vital sign measurements between treatment arms.

STUDY DESIGN

We analyzed RFM data from SAIL participants at 5 trial sites. We assessed tidal volumes, rates of airway obstruction, and mask leak among infants allocated to sustained inflations and IPPV, and we compared pulse rate and oxygen saturation measurements between treatment groups.

RESULTS

Among 70 SAIL participants (36 sustained inflations, 34 IPPV) with RFM measurements, 40 (57%) were spontaneously breathing prior to the randomized intervention. The median expiratory tidal volume of sustained inflations administered was 5.3 mL/kg (IQR 1.1-9.2). Significant mask leak occurred in 15% and airway obstruction occurred during 17% of sustained inflations. Among 34 control infants, the median expiratory tidal volume of IPPV inflations was 4.3 mL/kg (IQR 1.3-6.6). Mask leak was present in 3%, and airway obstruction was present in 17% of IPPV inflations. There were no significant differences in pulse rate or oxygen saturation measurements between groups at any point during resuscitation.

CONCLUSION

Expiratory tidal volumes of sustained inflations and IPPV inflations administered in the SAIL trial were highly variable in both treatment arms. Vital sign values were similar between groups throughout resuscitation. Sustained inflation as operationalized in the SAIL trial was not superior to IPPV to promote lung aeration after birth in this study subgroup.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT02139800.

Continuous positive airway pressure (CPAP) for respiratory distress in preterm infants

BACKGROUND

Respiratory distress, particularly respiratory distress syndrome (RDS), is the single most important cause of morbidity and mortality in preterm infants. In infants with progressive respiratory insufficiency, intermittent positive pressure ventilation (IPPV) with surfactant has been the usual treatment, but it is invasive, potentially resulting in airway and lung injury. Continuous positive airway pressure (CPAP) has been used for the prevention and treatment of respiratory distress, as well as for the prevention of apnoea, and in weaning from IPPV. Its use in the treatment of RDS might reduce the need for IPPV and its sequelae.

OBJECTIVES

To determine the effect of continuous distending pressure in the form of CPAP on the need for IPPV and associated morbidity in spontaneously breathing preterm infants with respiratory distress.

SEARCH METHODS

We used the standard strategy of Cochrane Neonatal to search CENTRAL (2020, Issue 6); Ovid MEDLINE and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Daily and Versions; and CINAHL on 30 June 2020. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

All randomised or quasi-randomised trials of preterm infants with respiratory distress were eligible. Interventions were CPAP by mask, nasal prong, nasopharyngeal tube or endotracheal tube, compared with spontaneous breathing with supplemental oxygen as necessary.

DATA COLLECTION AND ANALYSIS

We used standard methods of Cochrane and its Neonatal Review Group, including independent assessment of risk of bias and extraction of data by two review authors. We used the GRADE approach to assess the certainty of evidence. Subgroup analyses were planned on the basis of birth weight (greater than or less than 1000 g or 1500 g), gestational age (groups divided at about 28 weeks and 32 weeks), timing of application (early versus late in the course of respiratory distress), pressure applied (high versus low) and trial setting (tertiary compared with non-tertiary hospitals; high income compared with low income) MAIN RESULTS: We included five studies involving 322 infants; two studies used face mask CPAP, two studies used nasal CPAP and one study used endotracheal CPAP and continuing negative pressure for a small number of less ill babies. For this update, we included one new trial. CPAP was associated with lower risk of treatment failure (death or use of assisted ventilation) (typical risk ratio (RR) 0.64, 95% confidence interval (CI) 0.50 to 0.82; typical risk difference (RD) -0.19, 95% CI -0.28 to -0.09; number needed to treat for an additional beneficial outcome (NNTB) 6, 95% CI 4 to 11; I² = 50%; 5 studies, 322 infants; very low-certainty evidence), lower use of ventilatory assistance (typical RR 0.72, 95% CI 0.54 to 0.96; typical RD -0.13, 95% CI -0.25 to -0.02; NNTB 8, 95% CI 4 to 50; I² = 55%; very low-certainty evidence) and lower overall mortality (typical RR 0.53, 95% CI 0.34 to 0.83; typical RD -0.11, 95% CI -0.18 to -0.04; NNTB 9, 95% CI 2 to 13; I² = 0%; 5 studies, 322 infants; moderate-certainty evidence). CPAP was associated with increased risk of pneumothorax (typical RR 2.48, 95% CI 1.16 to 5.30; typical RD 0.09, 95% CI 0.02 to 0.16; number needed to treat for an additional harmful outcome (NNTH) 11, 95% CI 7 to 50; I² = 0%; 4 studies, 274 infants; low-certainty evidence). There was no evidence of a difference in bronchopulmonary dysplasia, defined as oxygen dependency at 28 days (RR 1.04, 95% CI 0.35 to 3.13; I² = 0%; 2 studies, 209 infants; very low-certainty evidence). The trials did not report use of surfactant, intraventricular haemorrhage, retinopathy of prematurity, necrotising enterocolitis and neurodevelopment outcomes in childhood.

AUTHORS' CONCLUSIONS

In preterm infants with respiratory distress, the application of CPAP is associated with reduced respiratory failure, use of mechanical ventilation and mortality and an increased rate of pneumothorax compared to spontaneous breathing with supplemental oxygen as necessary. Three out of five of these trials were conducted in the 1970s. Therefore, the applicability of these results to current practice is unclear. Further studies in resource-poor settings should be considered and research to determine the most appropriate pressure level needs to be considered.

[Safety evaluation on different ventilation strategies set for neonatal respiratory distress syndrome: a network Meta-analysis]

Objective: To evaluate the relative safety of different ventilation methods regarding mortality and rates of complication, on neonatal respiratory distress syndrome (NRDS). Methods: Network Meta-analysis was used to collect data on randomized controlled trials of pulmonary ventilation strategies in preterm infants with a mean gestational age of less than 32 weeks. Diagnostic criteria on NRDS were published in the PubMed, Cochrane, Web of Science, EBSCO, and Springer Link databases from January 1986 to June 2018. Revman 5.3 software was used to evaluate the quality of studies, based on the Cochrane quality assessment tool. Data were analyzed by Bayesian and frequency methods, using both Win BUGS 1.4.3 and STATA 13.0 software. Safety of different ventilation strategies for NRDS mortality and complications would include intraventricular hemorrhage (IVH), patent ductus arteriosus (PDA) and retinopathy of prematurity (ROP) and were evaluated. Counted data was displayed by OR and 95%CI. Results: A total of 31 RCTs were included in this paper, including 5 827 preterm infants and 11 ventilation strategies. There were no statistically significant differences appearing in 11 ventilation strategies on mortality, PDA or ROP. IVH results were reported in 28 studies. Compared with nasal intermittent positive pressure ventilation (NIPPV), both high- frequency oscillation ventilation (HFOV) (OR=3.33, 95%CI: 1.08-16.67, P<0.05) and synchronized intermittent mechanical ventilation (SIMV) (OR=8.22, 95%CI: 1.25-29.44, P<0.05) schemes seemed to have increased the risk of IVH in preterm infants with NRDS. NIPPV appeared the optimal ventilation strategy in the rankings of cumulative probability. Results on clustering showed that NIPPV was probably the best ventilation strategy for children with NRDS after considering the orders of IVH, PDA and ROP on mortality, respectively. However, HFOV, IMV, and SIMV did not seem to be the ideal ventilated strategies. Conclusions: Most of the clinical decision makers might prefer using NIPPV in the treatment of children with NRDS through mechanical ventilation systems to reduce both the incidence and death caused by IVH, PDA and ROP. It was not recommended to use HFOV, SIMV and IMV in treating NRDS with gestational less than 32 weeks. We suggested that larger numbers of multi-center RCTs ba carried out to make the above conclusions more convincing.

Effect of sustained inflations and intermittent positive pressure ventilation on bronchopulmonary dysplasia or death among neonatal: A protocol for systematic review

BACKGROUND

Sustained Inflations (SI) and Intermittent Positive Pressure Ventilation (IPPV) are two interventions to prevent Bronchopulmonary dysplasia (BPD). The aim of this study is to assess the effect of these two interventions.

METHODS

The databases of PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) will be comprehensively searched from inception to September 2019. All RCTs and quasi-RCTs which compare the efficacy of SI vs IPPV among preterm infants are eligible. We will assess the methodological quality using the Cochrane Handbook version 5.1.0. A meta-analysis will be performed using RevMan 5.3 software and the results will be presented using risk ratios (RRs) and 95% confidence intervals (CIs).

CONCLUSIONS

This study will provide strong evidence for assessing the effect of SI and IPPV on BPD or death among preterm infants.

PROSPERO REGISTRATION NUMBER

CRD42019135816.

Predictors of death including quality of positive pressure ventilation during newborn resuscitation and the relationship to outcome at seven days in a rural Tanzanian hospital

Background

Effective positive pressure ventilation (PPV) of non-breathing newborns is crucial in facilitating cardio-respiratory adaptation at birth. Identifying predictors of death in newborns receiving PPV is important in order to facilitate preventative strategies.

Objective

The objective of this study was to determine the perinatal predictors of death including the quality of PPV administered among admitted newborns.

Methods

An observational study of admitted newborns who received PPV after birth was conducted. Research assistants observed all deliveries and recorded perinatal events on data collection forms. Measured heart rate (HR) and ventilation parameters were then compared between newborns who died and survivors.

Results

Newborns (n = 232) were studied between October 2014 and November 2016. Newborns who died (n = 53) compared to survivors (n = 179) had more fetal heart rate (FHRT) abnormalities (12/53 vs 19/179; p = 0.03); lower initial HR (<100 beats/minute) at start of PPV (44/48 vs 77/139; p<0.001); and a longer time for HR to increase >100 beats/minute from birth (180 vs 149 seconds; p = 0.07). Newborns who died compared to survivors took longer time (14 vs 4 seconds; p = 0.008) and more inflations (7 vs 3; p = 0.006) to achieve an expired volume (V_t) of 6 ml/kg, respectively. Median delivered V_t during the first 60 seconds of PPV was less in newborns who died compared to survivors (5 vs 6 ml/kg; p = 0.12). Newborns who died proceeded to severe encephalopathy (15/31 vs 1/59; p<0.001) compared to survivors.

Conclusion

Depressed newborns who proceeded to death compared to survivors, exhibited delayed HR response to PPV which may partly reflect FHRT abnormalities related to interruption of placental blood flow, and/or a timely delay in establishing adequate V_t. Depressed newborns progressed to moderate/severe encephalopathy. Improving FHRT monitoring to identify fetuses at risk for expedited delivery, coupled with optimizing delivery room PPV might decrease mortality in this setting.

[Comparison of clinical efficacy of two noninvasive respiratory support therapies for respiratory distress syndrome in very low birth weight preterm infants]

OBJECTIVE

To compare the clinical efficacy of nasal intermittent positive pressure ventilation (NIPPV) and heated humidified high flow nasal cannula (HHHFNC) in the treatment of respiratory distress syndrome (RDS) among very low birth weight (VLBW) preterm infants.

METHODS

A total of 89 very low birth weight premature infants with respiratory distress syndrome (RDS) who were randomly administered with NIPPV (n=46) and HHHFNC (n=43) as an initial respiratory support. The incidence of initial treatment failure, the usage of pulmonary surfactant (PS), the parameters of respiratory support treatment and the incidence of complications were compared between the two groups.

RESULTS

There were no significant differences between the NIPPV and HHHFNC groups in the following items: the rate of intubation within 72 hours, rate of PS use, duration of invasive or non-invasive mechanical ventilation, duration of oxygen therapy, and incidence rates of severe apnea and pneumonia (P>0.05). There were also no significant differences in the incidence rates of bronchopulmonary dysplasia, necrotizing enterocolitis, retinopathy of prematurity, patent ductus arteriosus, intracranial hemorrhage, and air leak between the two group (P>0.05). The incidence rate of nose injury in the NIPPV group was higher than that in the HHHFNC group (P<0.05).

CONCLUSIONS

As an initial respiratory support for very low birth weight preterm infants with RDS, HHHFNC has a similar clinical effect as NIPPV, suggesting that HHHFNC is a safe and effective clinical option as a non-invasive ventilation treatment.

[Research advances in neonatal nasal intermittent positive pressure ventilation]

Nasal intermittent positive pressure ventilation (NIPPV) can augment nasal continuous positive airway pressure (nCPAP) by delivering intermittent positive pressure ventilation in a noninvasive way and can provide a new option for neonatal noninvasive respiratory support. NIPPV has an advantage over nCPAP in primary and post-extubation respiratory support. Moreover, it can reduce severe apnea of prematurity. Synchronized NIPPV has promising application prospects. This review article summarizes the advances in the application of NIPPV in neonatal respiratory support to promote the understanding and standardization of this technique.

[Research advances in neonatal nasal intermittent positive pressure ventilation]

Nasal intermittent positive pressure ventilation (NIPPV) can augment nasal continuous positive airway pressure (nCPAP) by delivering intermittent positive pressure ventilation in a noninvasive way and can provide a new option for neonatal noninvasive respiratory support. NIPPV has an advantage over nCPAP in primary and post-extubation respiratory support. Moreover, it can reduce severe apnea of prematurity. Synchronized NIPPV has promising application prospects. This review article summarizes the advances in the application of NIPPV in neonatal respiratory support to promote the understanding and standardization of this technique.

Nasal intermittent positive pressure ventilation (NIPPV) versus nasal continuous positive airway pressure (NCPAP) for preterm neonates after extubation

BACKGROUND

Previous randomised trials and meta-analyses have shown that nasal continuous positive airway pressure (NCPAP) is a useful method for providing respiratory support after extubation. However, this treatment sometimes 'fails' in infants, and they may require endotracheal re-intubation with its attendant risks and expense. Nasal intermittent positive pressure ventilation (NIPPV) can augment NCPAP by delivering ventilator breaths via nasal prongs. Older children and adults with chronic respiratory failure benefit from NIPPV, and the technique has been applied to neonates. However, serious side effects including gastric perforation have been reported with older methods of providing NIPPV.

OBJECTIVES

Primary objective To compare effects of management with NIPPV versus NCPAP on the need for additional ventilatory support in preterm infants whose endotracheal tube was removed after a period of intermittent positive pressure ventilation. Secondary objectives To compare rates of gastric distension, gastrointestinal perforation, necrotising enterocolitis and chronic lung disease; duration of hospitalisation; and rates of apnoea, air leak and mortality for NIPPV and NCPAP.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 9), MEDLINE via PubMed (1966 to 28 September 2015), Embase (1980 to 28 September 2015) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 28 September 2015). We also searched clinical trials databases, conference proceedings and reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

We included randomised and quasi-randomised trials comparing use of NIPPV versus NCPAP in extubated preterm infants. NIPPV included non-invasive support delivered by a mechanical ventilator or a bilevel device in a synchronised or non-synchronised way. Participants included ventilated preterm infants who were ready to be extubated to non-invasive respiratory support. Interventions compared were NIPPV, delivered by short nasal prongs or nasopharyngeal tube, and NCPAP, delivered by the same methods.Types of outcomes measures included failure of therapy (respiratory failure, rates of endotracheal re-intubation); gastrointestinal complications (i.e. abdominal distension requiring cessation of feeds, gastrointestinal perforation or necrotising enterocolitis); pulmonary air leak; chronic lung disease (oxygen requirement at 36 weeks' postmenstrual age) and mortality.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data regarding clinical outcomes including extubation failure; endotracheal re-intubation; rates of apnoea, gastrointestinal perforation, feeding intolerance, necrotising enterocolitis, chronic lung disease and air leak; and duration of hospital stay. We analysed trials using risk ratio (RR), risk difference (RD) and the number needed to treat for an additional beneficial outcome (NNTB) or an additional harmful outcome (NNTH) for dichotomous outcomes, and mean difference (MD) for continuous outcomes. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the quality of evidence.

MAIN RESULTS

Through the search, we identified 10 trials enrolling a total of 1431 infants and comparing extubation of infants to NIPPV or NCPAP. Three trials had methodological limitations and possible selection bias.Five trials used the synchronised form of NIPPV, four used the non-synchronised form and one used both methods. Eight studies used NIPPV delivered by a ventilator, one used a bilevel device and one used both methods. When all studies were included, meta-analysis demonstrated a statistically and clinically significant reduction in the risk of meeting extubation failure criteria (typical RR 0.70, 95% CI 0.60 to 0.80; typical RD -0.13, 95% CI -0.17 to -0.08; NNTB 8, 95% CI 6 to 13; 10 trials, 1431 infants) and needing re-intubation (typical RR 0.76, 95% CI 0.65 to 0.88; typical RD -0.10, 95% CI -0.15 to -0.05; NNTB 10, 95% CI 7 to 20; 10 trials, 1431 infants). We graded evidence for these outcomes as moderate, as all trial interventions were unblinded. Although methods of synchronisation varied (Graseby capsule or pneumotachograph/flow-trigger), the five trials that synchronised NIPPV showed a statistically significant benefit for infants extubated to NIPPV in terms of prevention of extubation failure up to one week after extubation.Unsynchronised NIPPV also reduced extubation failure. NIPPV provided via a ventilator is more beneficial than that provided by bilevel devices in reducing extubation failure during the first week. When comparing interventions, investigators found no significant reduction in rates of chronic lung disease (typical RR 0.94, 95% CI 0.80 to 1.10; typical RD -0.02, 95% CI -0.08 to 0.03) or death, and no difference in the incidence of necrotising enterocolitis. Air leaks were reduced in infants randomised to NIPPV (typical RR 0.48, 95% CI 0.28 to 0.82; typical RD -0.03, 95% CI -0.05 to -0.01; NNTB 33, 95% CI 20 to 100). We graded evidence quality as moderate (unblinded studies) or low (imprecision) for secondary outcomes.

AUTHORS' CONCLUSIONS

Implications for practice NIPPV reduces the incidence of extubation failure and the need for re-intubation within 48 hours to one week more effectively than NCPAP; however, it has no effect on chronic lung disease nor on mortality. Synchronisation may be important in delivering effective NIPPV. The device used to deliver NIPPV may be important; however, data are insufficient to support strong conclusions. NIPPV does not appear to be associated with increased gastrointestinal side effects. Implications for research Large trials should establish the impact of synchronisation of NIPPV on safety and efficacy of the technique and should compare the efficacy of bilevel devices versus a ventilator for providing NIPPV.

Early nasal intermittent positive pressure ventilation (NIPPV) versus early nasal continuous positive airway pressure (NCPAP) for preterm infants

BACKGROUND

Nasal continuous positive airway pressure (NCPAP) is a strategy for maintaining positive airway pressure throughout the respiratory cycle through the application of bias flow of respiratory gas to an apparatus attached to the nose. Treatment with NCPAP is associated with decreased risk of mechanical ventilation and might be effective in reducing chronic lung disease. Nasal intermittent positive pressure ventilation (NIPPV) is a form of noninvasive ventilation during which patients are exposed intermittently to higher levels of airway pressure, along with NCPAP through the same nasal device.

OBJECTIVES

To examine the risks and benefits of early NIPPV versus early NCPAP alone for preterm infants at risk of or in respiratory distress within the first hours after birth.Primary endpoints are respiratory failure and the need for intubated ventilatory support during the first week of life. Secondary endpoints include chronic lung disease (CLD) (oxygen therapy at 36 weeks' postmenstrual age), air leaks, duration of respiratory support, duration of oxygen therapy, intraventricular hemorrhage, and incidence of mortality.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 9), MEDLINE via PubMed (1966 to September 28, 2015), Embase (1980 to September 28, 2015), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to September 28, 2015). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomized controlled trials and quasi-randomized trials. A member of the Cochrane Neonatal Review Group handsearched abstracts from the European Society of Pediatric Research (ESPR). We contacted the authors of ongoing clinical trials to ask for information.

SELECTION CRITERIA

We considered all randomized and quasi-randomized controlled trials. Studies selected compared NIPPV versus NCPAP treatment, starting at birth or shortly thereafter in preterm infants (< 37 weeks' gestational age).

DATA COLLECTION AND ANALYSIS

We performed data collection and analysis using the recommendations of the Cochrane Neonatal Review Group.

MAIN RESULTS

Ten trials, enrolling a total of 1061 infants, met criteria for inclusion in this review. Meta-analyses of these studies showed significantly reduced risk of meeting respiratory failure criteria (typical risk ratio (RR) 0.65, 95% confidence interval (CI) 0.51 to 0.82; typical risk difference (RD) -0.09, 95% CI -0.13 to -0.04) and needing intubation (typical RR 0.78, 95% CI 0.64 to 0.94; typical RD -0.07, 95% CI -0.12 to -0.02) among infants treated with early NIPPV compared with early NCPAP. The meta-analysis did not demonstrate a reduction in the risk of CLD among infants randomized to NIPPV (typical RR 0.78, 95% CI 0.58 to 1.06). Investigators observed no evidence of harm. Review authors graded the quality of the evidence as moderate (unblinded studies).

AUTHORS' CONCLUSIONS

Early NIPPV does appear to be superior to NCPAP alone for decreasing respiratory failure and the need for intubation and endotracheal tube ventilation among preterm infants with respiratory distress syndrome. Additional studies are needed to confirm these results and to assess the safety of NIPPV compared with NCPAP alone in a larger patient population.

Is servoventilation in central sleep apnea syndrom still working?

Last black box on adaptive servoventilation in central apnoea syndrome generate many connective problems concerning the alternative therapies. The authors are starting from two recent french articles on this same subject and are trying to see what is missing and what we have to do.

Continuous distending pressure for respiratory distress in preterm infants

BACKGROUND

Respiratory distress syndrome (RDS) is the single most important cause of morbidity and mortality in preterm infants. In infants with progressive respiratory insufficiency, intermittent positive pressure ventilation (IPPV) with surfactant is the standard treatment for the condition, but it is invasive, potentially resulting in airway and lung injury. Continuous distending pressure (CDP) has been used for the prevention and treatment of RDS, as well as for the prevention of apnoea, and in weaning from IPPV. Its use in the treatment of RDS might reduce the need for IPPV and its sequelae.

OBJECTIVES

To determine the effect of continuous distending pressure (CDP) on the need for IPPV and associated morbidity in spontaneously breathing preterm infants with respiratory distress.Subgroup analyses were planned on the basis of birth weight (> or < 1000 or 1500 g), gestational age (groups divided at about 28 weeks and 32 weeks), methods of application of CDP (i.e. CPAP and CNP), application early versus late in the course of respiratory distress and high versus low pressure CDP and application of CDP in tertiary compared with non-tertiary hospitals, with the need for sensitivity analysis determined by trial quality.At the 2008 update, the objectives were modified to include preterm infants with respiratory failure.

SEARCH METHODS

We used the standard search strategy of the Neonatal Review Group. This included searches of the Oxford Database of Perinatal Trials, the Cochrane Central Register of Controlled Trials (CENTRAL, 2015 Issue 4), MEDLINE (1966 to 30 April 2015) and EMBASE (1980 to 30 April 2015) with no language restriction, as well as controlled-trials.com, clinicaltrials.gov and the International Clinical Trials Registry Platform of the World Health Organization (WHO).

SELECTION CRITERIA

All random or quasi-random trials of preterm infants with respiratory distress were eligible. Interventions were continuous distending pressure including continuous positive airway pressure (CPAP) by mask, nasal prong, nasopharyngeal tube or endotracheal tube, or continuous negative pressure (CNP) via a chamber enclosing the thorax and the lower body, compared with spontaneous breathing with oxygen added as necessary.

DATA COLLECTION AND ANALYSIS

We used standard methods of The Cochrane Collaboration and its Neonatal Review Group, including independent assessment of trial quality and extraction of data by each review author.

MAIN RESULTS

We included six studies involving 355 infants - two using face mask CPAP, two CNP, one nasal CPAP and one both CNP (for less ill babies) and endotracheal CPAP (for sicker babies). For this update, we included no new trials.Continuous distending pressure (CDP) is associated with lower risk of treatment failure (death or use of assisted ventilation) (typical risk ratio (RR) 0.65, 95% confidence interval (CI) 0.52 to 0.81; typical risk difference (RD) -0.20, 95% CI -0.29 to -0.10; number needed to treat for an additional beneficial outcome (NNTB) 5, 95% CI 4 to 10; six studies; 355 infants), lower overall mortality (typical RR 0.52, 95% CI 0.32 to 0.87; typical RD -0.15, 95% CI -0.26 to -0.04; NNTB 7, 95% CI 4 to 25; six studies; 355 infants) and lower mortality in infants with birth weight above 1500 g (typical RR 0.24, 95% CI 0.07 to 0.84; typical RD -0.28, 95% CI -0.48 to -0.08; NNTB 4, 95% CI 2.00 to 13.00; two studies; 60 infants). Use of CDP is associated with increased risk of pneumothorax (typical RR 2.64, 95% CI 1.39 to 5.04; typical RD 0.10, 95% CI 0.04 to 0.17; number needed to treat for an additional harmful outcome (NNTH) 17, 95% CI 17.00 to 25.00; six studies; 355 infants). We found no difference in bronchopulmonary dysplasia (BPD), defined as oxygen dependency at 28 days (three studies, 260 infants), as well as no difference in outcome at nine to 14 years (one study, 37 infants).

AUTHORS' CONCLUSIONS

In preterm infants with respiratory distress, the application of CDP as CPAP or CNP is associated with reduced respiratory failure and mortality and an increased rate of pneumothorax. Four out of six of these trials were done in the 1970s. Therefore, the applicability of these results to current practice is difficult to assess. Further research is required to determine the best mode of administration.

[A randomized controlled study of nasal intermittent positive pressure ventilation in the treatment of neonatal respiratory distress syndrome]

OBJECTIVE

To compare the clinical effects of nasal intermittent positive pressure ventilation (NIPPV) and nasal continuous positive airway pressure (NCPAP) in the treatment of neonatal respiratory distress syndrome.

METHODS

A prospective, randomized, controlled, single-center study was performed on 67 premature infants with NRDS between March 2011 and May 2012 and selected according to the inclusion and exclusion criteria. These premature infants were randomly assigned to receive NIPPV and NCPAP. Oxygenation index (OI), pH, PaCO2, duration of respiratory support, complications, success rate, hospital mortality, and incidence of bronchopulmonary dysplasia (BPD) were compared between the two groups.

RESULTS

Sixty-two patients were finally enrolled in the study, including 32 cases in the NIPPV group and 30 cases in the NCPAP group. After one hour of non-invasive ventilation, OI in the NIPPV group was higher than the NCPAP group (P<0.05), but there were no significant differences in pH and PaCO2 between the two groups (P>0.05 for both). A significantly lower proportion of infants needed mechanical ventilation via endotracheal tube (MVET) when they were treated initially with NIPPV than when they were treated initially with NCPAP (P<0.05). The NIPPV group had a significant higher success rate than the NCPAP group (P<0.05), but there was no significant difference in duration of respiratory support between the two groups (P>0.05). In addition, no significant differences in incidence of pneumothorax, hospital mortality and incidence of BPD were seen between the two groups (P>0.05 for all).

CONCLUSIONS

Compared with NCPAP, NIPPV can significantly decrease the proportion of premature infants with NRDS in need of MVET. However, there is no evidence that NIPPV can significantly reduce hospital mortality and incidence of BPD in premature infants with NRDS.

A trial comparing noninvasive ventilation strategies in preterm infants

BACKGROUND

To reduce the risk of bronchopulmonary dysplasia in extremely-low-birth-weight infants, clinicians attempt to minimize the use of endotracheal intubation by the early introduction of less invasive forms of positive airway pressure.

METHODS

We randomly assigned 1009 infants with a birth weight of less than 1000 g and a gestational age of less than 30 weeks to one of two forms of noninvasive respiratory support--nasal intermittent positive-pressure ventilation (IPPV) or nasal continuous positive airway pressure (CPAP)--at the time of the first use of noninvasive respiratory support during the first 28 days of life. The primary outcome was death before 36 weeks of postmenstrual age or survival with bronchopulmonary dysplasia.

RESULTS

Of the 497 infants assigned to nasal IPPV for whom adequate data were available, 191 died or survived with bronchopulmonary dysplasia (38.4%), as compared with 180 of 490 infants assigned to nasal CPAP (36.7%) (adjusted odds ratio, 1.09; 95% confidence interval, 0.83 to 1.43; P=0.56). The frequencies of air leaks and necrotizing enterocolitis, the duration of respiratory support, and the time to full feedings did not differ significantly between treatment groups.

CONCLUSIONS

Among extremely-low-birth-weight infants, the rate of survival to 36 weeks of postmenstrual age without bronchopulmonary dysplasia did not differ significantly after noninvasive respiratory support with nasal IPPV as compared with nasal CPAP. (Funded by the Canadian Institutes of Health Research; NIPPV ClinicalTrials.gov number, NCT00433212; Controlled-Trials.com number, ISRCTN15233270.).

Noninvasive respiratory support in the preterm infant

Multiple randomized controlled trials have suggested that nasal intermittent positive pressure ventilation, compared with nasal continuous airway pressure, prevents extubation failure and may decrease bronchopulmonary dysplasia. This article summarizes these studies and suggests strategies for the use of nasal intermittent positive pressure ventilation in neonates.

RDS--CPAP or surfactant or both

There is mounting evidence that early continuous positive airway pressure (CPAP) from birth is feasible and safe even in very preterm infants. However, many infants will develop respiratory distress syndrome (RDS) and require surfactant treatment. Combining a non-invasive ventilation approach with a strategy for surfactant administration is important, but questions remain about the optimal timing, mode of delivery and the value of predictive tests for surfactant deficiency.

CONCLUSION

Early CPAP in very preterm infants is as safe as routine intubation in the delivery room. However, a strategy for surfactant administration should be part of a non-invasive ventilation approach for those infants at risk of developing significant RDS.

[Nasal synchronized intermittent positive pressure ventilation for the treatment of apnea in preterm infants]

OBJECTIVE

To compare the efficacy of nasal synchronized intermittent positive pressure ventilation (NSIPPV) and nasal continuous positive airway pressure ventilation (NCPAP) for the treatment of apnea in preterm infants.

METHODS

Eighty preterm infants with apnea from August 2010 to January 2011 were randomly administered with NSIPPV and NCPAP (n=40 each).The blood gas results before and 2 hrs after ventilation, time of using ventilator, therapeutic efficacy and complications were compared between the two groups.

RESULTS

There were no significant differences in the blood gas results between the two groups before ventilation. The blood gas results (pH, PO2, PCO2) in the NSIPPV group were better than those in the NCPAP group 2 hrs after ventilation. The time of using ventilator in the NSIPPV group was shorter than that in the NCPAP group (50±9 h vs 91±11 h; P<0.01). There were no significant differences in the total effective rate between the NSIPPV and the NCPAP groups (95% vs 85%; P>0.05). The proportion of ventilator weaning within 3 days in the NSIPPV group (23/40) was higher than that in the NCPAP group (14/40) (P<0.05). The incidence of complications in the NSIPPV group was not different from that in the NCPAP group (22% vs 25%).

CONCLUSIONS

NSIPPV appears to be superior to NCPAP for the treatment of apnea in preterm infants.

Neonatal nasal intermittent positive pressure ventilation: what do we know in 2007?

Although neonatal nasal intermittent positive pressure ventilation (NIPPV) is widely used today, its place in neonatal respiratory support is yet to be fully defined. Current evidence indicates that NIPPV after extubation of very premature infants reduces the rate of reintubation. However, much is still not known about NIPPV including its mechanisms of action. It may improve pulmonary mechanisms, tidal volume and minute ventilation but more studies are required to confirm these findings. There is some evidence that NIPPV marginally improves gas exchange. More research is needed to establish which device is best, what settings to use or whether to use synchronised rather than non-synchronised NIPPV, and about the way to wean NIPPV. Future studies should enrol sufficient infants to detect uncommon serious complications and include long-term follow up to determine important neurodevelopment and pulmonary outcomes.

Tracheoscopy assisted repair of tracheo-esophageal fistula (TARTEF): a 10-year experience

BACKGROUND

Fiberoptic tracheoscopy assisted repair of tracheoesophageal fistula (TARTEF) has been reported to be useful for the surgeon with regards to identification of the fistula and proper fistula ligation. The aim of this article is to report our 10-year experience using TARTEF with intermittent positive pressure ventilation (IPPV) during tracheoesophageal fistula (TEF) repair in newborns.

METHODS

With ethical committee approval, we included all patients undergoing TARTEF from 1995-2005. Variables of interest were (1) respiratory deterioration caused by gastric inflation because of IPPV during surgery and endoscopy; (2) detection of additional airway anomalies; (3) success of intubation of the fistula; (4) other side effects or adverse events. Data are given in median and range.

RESULTS

Forty-seven neonates with TARTEF were included. Mean gestational age was 37 weeks (31-42) and mean weight was 2.5 kg (1.1-3.8). The patients were intubated with tracheal tubes size 2.5-3.5 mm ID. Appropriately sized fiberoptic bronchoscopes with an outer diameter of 2.0, 2.4 and 2.8 mm were used; passed through the lumen of the tracheal tube (TT) thereby requiring the use of IPPV to ensure adequate ventilation. No respiratory deterioration was noted as a consequence of intraoperative fiberoptic manipulation within the trachea or because of gastric hyperinflation with IPPV. In all patients, the TEF was successfully penetrated with the fiberscope and this clearly helped the surgeon to rapidly identify and dissect the fistula. In two patients a tracheal bronchus was identified. In two patients accidental extubation occurred during endoscopic confirmation of successful fistula repair.

CONCLUSIONS

While fiberoptic TARTEF through the tracheal tube with IPPV did expedite and facilitate surgery, it did not cause clinically relevant impairment of ventilation. Careful manipulation during fiberoptic assessment is required to avoid tube displacement.

Neuromotor outcome at 2 years of very preterm infants who were treated with high-frequency oscillatory ventilation or conventional ventilation for neonatal respiratory distress syndrome

OBJECTIVE

In a previous multicenter, randomized trial, elective use of high-frequency oscillatory ventilation was compared with the use of conventional ventilation in the management of respiratory distress syndrome in preterm infants <30 weeks. No difference in terms of respiratory outcome was observed, but concerns were raised about an increased rate of severe intraventricular hemorrhage in the high-frequency ventilation group. To evaluate outcome, a follow-up study was conducted until a corrected age of 2 years. We report the results concerning neuromotor outcome.

METHODS

Outcome was able to be evaluated in 192 of the 212 infants who survived until discharge from the neonatal unit: 97 of 105 infants of the high-frequency group and 95 of 104 infants of the conventional ventilation group.

RESULTS

In the infants reviewed, mean birth weight and gestational age were similar in the 2 ventilation groups. As in the overall study population, the following differences were observed between the high-frequency ventilation group and the conventional ventilation group: lower 5-minute Apgar score, fewer surfactant instillations, and a higher incidence of severe intraventricular hemorrhage. At a corrected age of 2 years, 93 of the 97 infants of the high-frequency group and 79 of the 95 infants of the conventional ventilation group did not present any neuromotor disability, whereas 4 infants of the high-frequency group and 16 infants of the conventional ventilation group had cerebral palsy.

CONCLUSIONS

Contrary to our initial concern about the increased rate of severe intraventricular hemorrhage in the high-frequency ventilation group, these data suggest that early use of high-frequency ventilation, compared with conventional ventilation, may be associated with a better neuromotor outcome. Because of the small number of patients studied and the absence of any explanation for this finding, we can conclude only that high-frequency oscillatory ventilation is not associated with a poorer neuromotor outcome.

Use of controlled ventilation in a clinical setting

Mechanical ventilation has long been used to maintain ventilation in humans when the lungs are rendered incapable of oxygenation or when respiration is affected by central nervous system depression, but it has only recently been applied to similar cases in dogs and cats. Although manual ventilation is still the more common form of ventilation in dogs and cats, mechanical intermittent positive-pressure ventilation (IPPV) is a much more efficient and reliable means of maintaining the highest quality of respiratory assistance. With proper training, technicians can use IPPV to support compromised animals until they are capable of maintaining normal oxygen concentrations.

A comparative study of continuous positive airway pressure (CPAP) and intermittent positive pressure ventilation (IPPV) in patients with flail chest

INTRODUCTION

The role of non-invasive positive pressure ventilation delivered through a face mask in patients with flail chest is uncertain. We conducted a prospective, randomised study of continuous positive airway pressure (CPAP) given via a face mask to spontaneously breathing patients compared with intermittent positive pressure ventilation (IPPV) with endotracheal intubation (ETI) in 52 patients with flail chest who required mechanical ventilation.

METHOD

The 52 mechanically ventilated patients were randomly divided into two treatment groups: the ET group (n = 27) received mechanical ventilation with ETI, whereas patients in the CPAP group (n = 25) received CPAP via a face mask with patient controlled analgesia (PCA). Major complications, arterial blood gas levels, length of intensive care unit (ICU) stay and ICU survival rate were recorded.

RESULTS

Nosocomial infection was diagnosed in 10 of 21 patients in the ET group, but only in 4 of 22 in the CPAP group (p = 0.001). Mean PO(2) was significantly higher in the ET group in the first 2 days (p<0.05). There were no significant differences in length of ICU stay between groups. Twenty CPAP patients survived, but only 14 of 21 intubated patients who received IPPV (p<0.01).

CONCLUSION

Non-invasive CPAP with PCA led to lower mortality and a lower nosocomial infection rate, but similar oxygenation and length of ICU stay. The study supports the application of CPAP at least as a first line of treatment for flail chest caused by blunt thoracic trauma.

How safe is intermittent positive pressure ventilation in preterm babies ventilated from delivery to newborn intensive care unit?

OBJECTIVES

To examine whether clinically determined ventilator settings will produce acceptable arterial blood gas values on arrival, in preterm infants ventilated from delivery to the newborn intensive care unit (NICU). Further, to examine the usefulness of tidal volume and minute ventilation measurements at this time.

DESIGN

A prospective observational cohort study in a tertiary level 3 NICU.

PATIENTS

Twenty six preterm infants requiring intubation and mechanical ventilation at the point of delivery to the NICU.

SETTING

Infants who required mechanical ventilation were monitored with a blinded Ventrak 1550 dynamic lung function monitor from the point of delivery to the NICU. A Dräger Babylog 2000 transport ventilator was set up to achieve adequate chest wall movement, and FIO(2) was adjusted to achieve preductal SaO(2) of 90-98%. Dynamic lung function monitoring data were recorded and related to the arterial blood gas taken on arrival.

RESULTS

Mean gestation was 28 weeks (range 23-34) and mean birth weight was 1180 g (range 480-4200). A quarter (26% (95% confidence interval (CI) 12% to 48%)) were hypocarbic, with 20% (95% CI 7% to 39%) below 25 mm Hg, and 38% (95% CI 20% to 60%) had hyperoxia. Some (20% (95% CI 7% to 39%)) were both hypocarbic and hyperoxic. Total minute ventilation per kilogram correlated significantly with the inverse of PaCO(2) (p < 0.001).

CONCLUSIONS

Clinically determining appropriate mechanical ventilation settings from the point of delivery to the NICU is difficult, and inadvertent overventilation may be common. Severe hyperoxia can occur in spite of adjustment of the FIO(2) concentration to achieve an SaO(2) range of 90-98%. Limiting minute ventilation during resuscitation may prevent hypocarbia.

Elimination of ventilator dead space during synchronized ventilation in premature infants

BACKGROUND

Mainstream airflow sensors used in neonatal ventilators to synchronize mechanical breaths with spontaneous inspiration and measure ventilation increase dead space and may impair carbon dioxide (CO(2)) elimination.

OBJECTIVE

To evaluate a technique consisting of a continuous gas leakage at the endotracheal tube (ETT) adapter to wash out the airflow sensor for synchronization and ventilation monitoring without CO(2) rebreathing in preterm infants.

DESIGN

Minute ventilation (V'(E)) by respiratory inductance plethysmography, end-inspiratory and end-expiratory CO(2) by side-stream microcapnography, and transcutaneous CO(2) tension (TcPCO(2)) were measured in 10 infants (body weight, 835+/-244 g; gestational age, 26+/-2 weeks; age, 19+/-9 days; weight, 856+/-206 g; ventilator rate, 21+/-6 beats/min; PIP, 16+/-1 centimeters of water (cmH(2)O); PEEP, 4.2+/-0.4 cmH(2)O; fraction of inspired oxygen (FIo(2)), 0.26+/-0.6). The measurements were made during four 30-minute periods in random order: IMV (without airflow sensor), IMV+Sensor, SIMV (with airflow sensor), and SIMV+Leak (ETT adapter continuous leakage).

RESULTS

Airflow sensor presence during SIMV and IMV+Sensor periods resulted in higher end-inspiratory and end-expiratory CO(2), Tcpco(2), and spontaneous V'(E) compared with IMV. These effects were not observed during SIMV+Leak.

CONCLUSIONS

The significant physiologic effects of airflow sensor dead space during synchronized ventilation in preterm infants can be effectively prevented by the ETT adapter continuous leakage technique.

Emergency ventilatory management in hemorrhagic states: elemental or detrimental?

BACKGROUND

A study was performed to demonstrate that slower respiratory rates (RRs) of positive-pressure ventilation can preserve adequate oxygenation and acid-base status in hemorrhagic states, whereas "normal" or higher RRs worsen hemodynamics.

METHODS

Eight swine (ventilated with 12 mL/kg tidal volume, 0.28 Fio(2); RR of 12 breaths/min) were hemorrhaged to < 65 mm Hg systolic arterial blood pressure (SABP). RRs were then sequentially changed every 10 minutes to 6, 20, 30, and 6 breaths/min.

RESULTS

With RRs at 6 breaths/min, the animals maintained pH > 7.25/Sao(2) > 99%, but increased mean SABP (from 65 to 84 mm Hg; p < 0.05), time-averaged coronary perfusion pressure (CPP) (from 50 +/- 2 to 60 +/- 4 mm Hg; p < 0.05), and cardiac output (Qt) (from 2.4 to 2.8 L/min; p < 0.05). With RRs of 20 and 30 breaths/min, SABP (73 and 66 mm Hg), CPP (47 +/- 3 and 42 +/- 4 mm Hg), and Qt (2.5 and 2.4 L/min) decreased, as did Pao(2) and Paco(2) (< 30 mm Hg), with p < 0.05 for each comparison, respectively. When RR returned to 6 breaths/min, SABP (95 mm Hg), CPP (71 +/- 6 mm Hg), and Qt (3.0 L/min) improved significantly (p < 0.05).

CONCLUSION

After even moderate levels of hemorrhage in animals, positive-pressure ventilation with "normal" or higher RRs can impair hemodynamics. Hemodynamics can be improved with lower RRs while still maintaining adequate oxygenation and ventilation.

Volume-guaranteed ventilation

Pressure-limited, time-cycled ventilation has been the primary mode of ventilation for neonates for several decades. But the realization that volume rather than pressure causes ventilator-induced lung injury has led to the development of new strategies for ventilation. Volume guarantee is a mode of ventilation that automatically adjusts the inspiratory pressure to achieve a set tidal volume according to changes in lung compliance or resistance or the patient's respiratory drive. Volume-guaranteed ventilation delivers a specific, preset volume of gas, and inspiration ends when it has been delivered. This mode of ventilation requires careful attention to the infant and to ventilator settings.

Tension pneumopericardium caused by positive pressure ventilation complicating anaerobic pneumonia

A 22-year-old man was admitted with pneumonia. He was immediately intubated and positive pressure ventilation was initiated. Blood and sputum cultures showed Bacteroides fragilis and Corynebacterium sp., which were treated with metronidazole and clindamycin. Three weeks later his blood pressure suddenly dropped with an elevation of the central venous pressure. Chest X-ray revealed a pneumopericardium. A parasternal mediastinotomy with partial pericardiectomy was immediately performed. On opening the pericardium his blood pressure normalised. The patient gradually recovered and six weeks after admission he was extubated. Two weeks later he was discharged. A pneumopericardium without previous thorax trauma is very rare and early recognition is imperative because a tension pneumopericardium with cardiac tamponade may develop, as happened in this case. A tension pneumopericardium has to be treated with immediate pericardiocentesis followed by partial pericardiectomy to avoid recurrence.

Prolonged ventilation and intact survival in very low birth weight infants

A requirement for prolonged ventilation (>28 days) has been associated with a poor outcome in infants. We postulated that in the present population of infants who usually receive antenatal steroids and post-natal surfactant, prolonged ventilation in discrete episodes, i.e. discontinuous intermittent positive pressure ventilation (IPPV), would have a better outcome than a requirement for prolonged ventilation continuously from birth (continuous IPPV) and, in addition, that an abnormal ultrasound scan appearance would be a reliable predictor of poor outcome in infants requiring prolonged ventilation. All very low birth weight (VLBW) infants ventilated for at least 28 days (prolonged ventilation) were identified from a prospectively maintained database. At 1 year of age, neurodevelopmental status was assessed and abnormal neurodevelopmental outcome diagnosed if the infant's Griffiths developmental quotient was at least two standard deviations below the mean and/or they had impairment with disability. Of 417 VLBW infants, 41 required prolonged ventilation (30 continuous and 11 discontinuous). In the continuous IPPV group, 18 and one in the discontinuous IPPV group died or had abnormal neurodevelopmental outcome ( P<0.01). All eight infants with major cranial ultrasound abnormalities died or had abnormal outcome ( P<0.01).

CONCLUSION

prolonged ventilation can be associated with intact survival, but not in very low birth weight infants with evidence of significant brain injury.

Continuous distending pressure for respiratory distress syndrome in preterm infants

BACKGROUND

Respiratory distress syndrome (RDS) is the single most important cause of morbidity and mortality in preterm infants (Greenough 1998, Bancalari 1992). Intermittent positive pressure ventilation (IPPV) with surfactant is the standard treatment for the condition. The major difficulty with IPPV is that it is invasive, resulting in airway and lung injury and contributing to the development of chronic lung disease.

OBJECTIVES

In spontaneously breathing preterm infants with RDS, to determine if continuous distending pressure (CDP) reduces the need for IPPV and associated morbidity without adverse effects.

SEARCH STRATEGY

The standard search strategy of the Neonatal Review group was used. This included searches of the Oxford Database of Perinatal Trials, Cochrane Controlled Trials Register (The Cochrane Library, Issue 1, 2002), MEDLINE (1966-January 2002), and EMBASE (1980-January 2002), previous reviews including cross references, abstracts, conference and symposia proceedings, expert informants, journal hand searching mainly in the English language.

SELECTION CRITERIA

All trials using random or quasi-random allocation of preterm infants with RDS were eligible. Interventions were continuous distending pressure including continuous positive airway pressure (CPAP) by mask, nasal prong, nasopharyngeal tube, or endotracheal tube, or continuous negative pressure (CNP) via a chamber enclosing the thorax and lower body, compared with standard care.

DATA COLLECTION AND ANALYSIS

Standard methods of the Cochrane Collaboration and its Neonatal Review Group were used, including independent assessment of trial quality and extraction of data by each author.

MAIN RESULTS

CDP is associated with a lower rate of failed treatment (death or use of assisted ventilation) [summary RR 0.70 (0.55, 0.88), RD -0.22 (-0.35, -0.09), NNT 5 (3, 11)], overall mortality [summary RR 0.52 (0.32, 0.87), RD -0.15 (-0.26, -0.04), NNT 7 (4, 25)], and mortality in infants with birthweights above 1500 g [summary RR 0.24 (0.07, 0.84), RD -0.281 (-0.483, -0.078), NNT 4 (2, 13)]. The use of CDP is associated with an increased rate of pneumothorax [summary RR 2.36 (1.25, 5.54), RD 0.14 (0.04, 0.23), NNH 7 (4, 24)].

REVIEWER'S CONCLUSIONS

In preterm infants with RDS the application of CDP either as CPAP or CNP is associated with benefits in terms of reduced respiratory failure and reduced mortality. CDP is associated with an increased rate of pneumothorax. The applicability of these results to current practice is difficult to assess, given the intensive care setting of the 1970s when four out of five of these trials were done. Where resources are limited, such as in developing countries, CPAP for RDS may have a clinical role. Further research is required to determine the best mode of administration and its role in modern intensive care settings

Lung salvage and protection ventilatory techniques

Physicians are in the beginning of an era in intensive care medicine in which they finally are starting to see improved outcomes in patients with AHRF. At the same time, intensivists are presented with a bewildering choice of ventilator options and adjunctive therapies. Trying to sort out which are "cosmetic," that is, improve the blood gases as opposed to influencing the outcome, remains a challenge and will be resolved only with additional RCTs. Principles of ventilator management that are driven by mimicking normal physiology are inappropriate and must be rethought.

[Survival with artificial respiration at home. An open, prospective study on home ventilation for neuromuscular diseases, in particular, the situation of ALS patients]

A growing number of patients with neuromuscular disease have been treated with home mechanical ventilation during the past 15 years. We prospectively examined the long-term effects and complications of this method, particularly with regard to noninvasive positive pressure ventilation (NPPV). Thirty-one patients with amyotrophic lateral sclerosis (ALS, n = 20) or other slowly progressive neuromuscular diseases (NMD, n = 11) were observed for 17,517 home ventilation days (almost 48 ventilation years). The mean observed ventilation time was 565 days (min/max: 30/2930). Twenty-five patients were ventilated noninvasively with different masks. The calculated mean survival with NPPV ventilation (criteria: death, tracheostomy, or patient deciding to break off) was 2052 (SE: +/- 317.8) days in the NMD group, 248 days (+/- 35.7) for ALS patients without bulbar symptoms, and 82 days (+/- 27.4) with bulbar paralysis. Complications with the need for intervention were observed six times more frequently with ALS than with NMD. NPPV is effective for years in patients with slowly progressing NMD. Those ALS patients without bulbar symptoms can profit for up to a year from NPPV, while those with bulbar paralysis can have some symptom relief. Complications of every kind are much more frequent in ALS patients.

Ventilatory support by continuous positive airway pressure breathing improves gas exchange as compared with partial ventilatory support with airway pressure release ventilation

In acute lung injury, airway pressure release ventilation (APRV) with superimposed spontaneous breathing improves gas exchange compared with controlled mechanical ventilation. However, the release of airway pressure below the continuous positive airway pressure (CPAP) level may provoke lung collapse. Therefore, we compared gas exchange and hemodynamics using a crossover design in nine pigs with oleic acid-induced lung injury during CPAP breathing and APRV with a release pressure level of 0 and 5 cm H(2)O. At an identical minute ventilation (V(E) 8 L/min) spontaneous breathing averaged 55%, 67%, and 100% of V(E) during the two APRV modes and CPAP, respectively. Because of the concept of APRV, mean airway pressure was highest during CPAP and lowest during APRV with a release pressure of 0 cm H(2)O. Shunt was reduced to almost half during CPAP (6.6% of Q(t)) compared with both APRV-modes (13.0% of Q(t)). Cardiac output and oxygen consumption, in contrast, were similar during all three ventilatory settings. Thus, in our lung injury model, CPAP was superior to partial ventilatory support using APRV with and without positive end-expiratory pressure. This may be attributable to beneficial effects of spontaneous breathing on gas exchange as well as to rapid lung collapse during the phases of airway pressure release below the CPAP level. These findings may suggest that the amount of mechanical ventilatory support using the APRV mode should be kept at the necessary minimum.

IMPLICATIONS

Oxygenation is better with continuous positive airway pressure breathing than with partial mechanical ventilatory support using airway pressure release ventilation. Therefore, mechanical ventilatory support achieved by a cyclic release of airway pressure during APRV should be kept at the minimum level that enables enough ventilatory support for patients to avoid respiratory muscle fatigue.

[Hemorrhagic and hypoxic-ischemic brain lesions in premature infants on artificial ventilation]

Major intraventricular hemorrhage (IVH) and cystic leucomalacia (PVL) are major causes of mortality and neurologic morbidity in premature infants that are strongly associated with long-term neurodevelopmental sequelae. Preterm babies ventilated by intermittent positive pressure ventilation are in higher risk for this type of lesion. We studied incidence of major intraventricular bleeding (with ventricular dilatation and parenchymal involvement) and cystic periventricular leucomalacia in 79 preterm babies who required mechanical ventilation for respiratory-distress syndrome (RDS), admitted on Department of Neonatology of the Pediatric University Hospital in Sarajevo from February 1999. to May 2000. Thirty-five babies were classified as less than 32 weeks of gestation. Major intraventricular hemorrhage and cystic leucomalacia were documented in 5 babies (10.2%) of 49 survivors. Two babies developed posthemmoragic hydrocephalus and required shunting. Severe brain damage was more common in ventilated infants with gestational age with (32 weeks of gestation (23.5%) compared with the babies > 32 weeks of gestation (2.9%). The severity of RDS also correlated with an increased risk of severe IVH.

Changing ventilator: An option to take into account in the treatment of persistent vomiting during nasal ventilation

Problems related with nasal intermittent positive pressure ventilation (NIPPV) are nasal and mouth dryness, soreness on the bridge of the nose, eye irritation and epistaxis. Gastrointestinal distention due to air swallowing has been reported in half of the patients. Acceleration of digestive function with drugs or reduction of the volume delivered to alleviate gastric distension are considered as the conventional treatment. It is also possible that the problem disappears spontaneously after a few weeks of NIPPV. We present a patient in whom conventional treatment was unsuccessful. When we changed to a different ventilator, symptoms disappeared, and the new one was very well tolerated. In our experience, changing ventilators should be included in the management of gastrointestinal distension due to NIPPV, especially if conventional procedures, such as drugs or gas flow modifications, fail.

Pneumothorax in adults with cystic fibrosis dependent on nasal intermittent positive pressure ventilation (NIPPV): a management dilemma

The management of pneumothorax in three adult patients with cystic fibrosis dependent on nasal intermittent positive pressure ventilation is described.