human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Nasal high flow ( NHF ) has been shown to increase expiratory pressure and reduce respiratory rate but the mechanisms involved remain unclear . Ten healthy participants [ age , 22 ± 2 yr ; body mass index ( BMI ) , 24 ± 2 kg/m(2 ) ] were recruited to determine ventilatory responses to NHF of air at 37 ° C and fully saturated with water . We conducted a r and omized , controlled , cross-over study consisting of four separate ∼60-min visits , each 1 wk apart , to determine the effect of NHF on ventilation during wakefulness ( NHF at 0 , 15 , 30 , and 45 liters/min ) and sleep ( NHF at 0 , 15 , and 30 liters/min ) . In addition , a nasal cavity model was used to compare pressure/air-flow relationships of NHF and continuous positive airway pressure ( CPAP ) throughout simulated breathing . During wakefulness , NHF led to an increase in tidal volume from 0.7 ± 0.1 liter to 0.8 ± 0.2 , 1.0 ± 0.2 , and 1.3 ± 0.2 liters , and a reduction in respiratory rate ( fR ) from 16 ± 2 to 13 ± 3 , 10 ± 3 , and 8 ± 3 breaths/min ( baseline to 15 , 30 , and 45 liters/min NHF , respectively ; P < 0.01 ) . In contrast , during sleep , NHF led to a ∼20 % fall in minute ventilation due to a decrease in tidal volume and no change in fR. In the nasal cavity model , NHF increased expiratory but decreased inspiratory resistance depending on both the cannula size and the expiratory flow rate . The mechanisms of action for NHF differ from those of CPAP and are sleep/wake-state dependent . NHF may be utilized to increase tidal breathing during wakefulness and to relieve respiratory loads during sleep Objective To determine survival and neonatal morbidity for babies born between 22 and 26 weeks ’ gestation in Engl and during 2006 , and to evaluate changes in outcome since 1995 for babies born between 22 and 25 weeks ’ gestation . Design Prospect i ve national cohort studies . Setting Maternity and neonatal units in Engl and . Participants 3133 births between 22 and 26 weeks ’ gestation in 2006 ; 666 admissions to neonatal units in 1995 and 1115 in 2006 of babies born between 22 and 25 weeks ’ gestation . Main outcome measures Survival to discharge from hospital , pregnancy and delivery outcomes , infant morbidity until discharge . Results In 2006 , survival of live born babies was 2 % ( n=3 ) for those born at 22 weeks ’ gestation , 19 % ( n=66 ) at 23 weeks , 40 % ( n=178 ) at 24 weeks , 66 % ( n=346 ) at 25 weeks , and 77 % ( n=448 ) at 26 weeks ( P<0.001 ) . At discharge from hospital , 68 % ( n=705 ) of survivors had bronchopulmonary dysplasia ( receiving supplemental oxygen at 36 weeks postmenstrual age ) , 13 % ( n=135 ) had evidence of serious abnormality on cerebral ultrasonography , and 16 % ( n=166 ) had laser treatment for retinopathy of prematurity . For babies born between 22 and 25 weeks ’ gestation from March to December , the number of admissions for neonatal care increased by 44 % , from 666 in 1995 to 959 in 2006 . By 2006 adherence to evidence based practice associated with improved outcome had significantly increased . Survival increased from 40 % to 53 % ( P<0.001 ) overall and at each week of gestation : by 9.5 % ( confidence interval −0.1 % to 19 % ) at 23 weeks , 12 % ( 4 % to 20 % ) at 24 weeks , and 16 % ( 9 % to 23 % ) at 25 weeks . The proportions of babies surviving in 2006 with bronchopulmonary dysplasia , major cerebral scan abnormality , or weight and /or head circumference < −2 SD were similar to those in 1995 , but the proportion treated for retinopathy of prematurity had increased from 13 % to 22 % ( P=0.006 ) . Predictors of mortality and morbidity were similar in both cohorts . Conclusion Survival of babies born between 22 and 25 weeks ’ gestation has increased since 1995 but the pattern of major neonatal morbidity and the proportion of survivors affected are unchanged . These observations reflect an important increase in the number of preterm survivors at risk of later health problems Objective : To compare the work of breathing ( WOB ) in premature neonates supported with high-flow nasal cannula ( HFNC ) and nasal continuous positive airway pressure ( NCPAP ) . Study Design : Eighteen preterm neonates < 2.0 kg on HFNC or NCPAP support were studied in a r and om order . A ventilator was used to deliver 6 cm H2O of NCPAP with nasal prongs . High-flow nasal cannula delivered with Vapotherm ( VAPO ) at 3 , 4 and 5 l/min was used . Tidal ventilation was obtained using respiratory inductance plethysmography calibrated with face-mask pneumotachography . An esophageal balloon estimated pleural pressure from which changes in end distending pressure were calculated . Inspiratory , elastic and resistive WOB and respiratory parameters were calculated . Results : No differences were found in the WOB for all setting s. Changes in end distending pressure did not vary significantly over all device setting s except VAPO at 5 l/min . Conclusion : In these preterm infants with mild respiratory illness , HFNC provided support comparable to NCPAP OBJECTIVE To determine the better approach for weaning preterm infants from nasal continuous positive airway pressure ( NCPAP ) with or without transitioning to nasal cannula ( NC ) .  DESIGN / METHODS This is a r and omized , open label , controlled trial . Preterm infants born at ≥28 weeks gestation who were clinical ly stable on NCPAP of 5 cm H(2)O with FiO(2)<0.30 for at least 24 h were r and omly assigned to one of 2 groups . The no-NC group were kept on NCPAP until they were on FiO(2)=0.21 for 24 h , and then were weaned off NCPAP completely without any exposure to NC . If they met failing criteria , NCPAP was re-instituted . The NC-group was weaned off NCPAP when FiO(2 ) was ≤0.30 to NC ( 2 L/min ) followed by gradual weaning from oxygen . Infants who failed NC were supported back with NCPAP for 24 h before making a second attempt of NC . RESULTS Sixty neonates were enrolled ; 30 in each group . The two groups were similar in birthweight , gestational age , sex , antenatal steroids , mode of delivery , use of surfactant and xanthines , and duration of mechanical ventilation . After r and omization , the no-NC group had fewer days on oxygen [ median ( interquartile range ) : 5 ( 1 - 8 ) vs 14 ( 7.5 - 19.25 ) days , p<0.001 ] and shorter duration of respiratory support [ 10.5 ( 4 - 21 ) vs 18 ( 11.5 - 29 ) days , p=0.03 ] . There were no differences between groups regarding success of weaning  from NCPAP . CONCLUSIONS Weaning preterm infants  from NCPAP to NC is associated with increased exposure to oxygen and longer duration of respiratory support Objective To compare patient comfort in preterm infants treated with heated humidified high flow nasal cannulae ( HHHFNC )  versus nasal continuous positive airway pressure ( NCPAP ) . Design R and omised cross-over trial ( 2 × 24 h ) . Setting Single tertiary neonatal unit . Patients 20 infants less than 34 weeks postmenstrual age treated with NCPAP due to mild respiratory illness . Interventions After parental consent , infants were r and omised to 24 h of treatment with NCPAP or HHHFNC followed by 24 h of the alternate therapy . Main outcome measures Primary outcome was patient comfort assessed by the EDIN ( neonatal pain and discomfort ) scale . Secondary outcomes were respiratory parameters ( respiratory rate , FiO2 , SpO2 , TcPCO2 ) , ambient noise , salivary cortisol and parental assessment s of their child . Results We found no differences between HHHFNC and NCPAP  in mean cumulative EDIN score ( 10.7 vs 11.1 , p=0.25 ) or ambient noise ( 70 vs 74 dBa , p=0.18 ) . Parents assessed HHHFNC treatment as significantly better in the three domains , 1 ) child satisfied , 2 ) parental contact and interaction and 3 ) possibility to take part in care . Mean respiratory rate over 24 h was lower during HHHFNC than CPAP ( 41 vs 46 , p=0.001 ) . Other respiratory parameters were similar . Conclusions Using EDIN scale , we found no difference in patient comfort with HHHFNC versus NCPAP . However , parents preferred HHHFNC , and during HHHFNC respiratory rate was lower than during NCPAP . Clinical Trials.gov , number NCT01526226 BACKGROUND There are limited data to inform the choice between early treatment with continuous positive airway pressure ( CPAP ) and early surfactant treatment as the initial support for extremely-low-birth-weight infants . METHODS We performed a r and omized , multicenter trial , with a 2-by-2 factorial design , involving infants who were born between 24 weeks 0 days and 27 weeks 6 days of gestation . Infants were r and omly assigned to intubation and surfactant treatment ( within 1 hour after birth ) or to CPAP treatment initiated in the delivery room , with subsequent use of a protocol -driven limited ventilation strategy . Infants were also r and omly assigned to one of two target ranges of oxygen saturation . The primary outcome was death or bronchopulmonary dysplasia as defined by the requirement for supplemental oxygen at 36 weeks ( with an attempt at withdrawal of supplemental oxygen in neonates who were receiving less than 30 % oxygen ) . RESULTS A total of 1316 infants were enrolled in the study . The rates of the primary outcome did not differ significantly between the CPAP group and the surfactant group ( 47.8 % and 51.0 % , respectively ; relative risk with CPAP , 0.95 ; 95 % confidence interval [ CI ] , 0.85 to 1.05 ) after adjustment for gestational age , center , and familial clustering . The results were similar when bronchopulmonary dysplasia was defined according to the need for any supplemental oxygen at 36 weeks ( rates of primary outcome , 48.7 % and 54.1 % , respectively ; relative risk with CPAP , 0.91 ; 95 % CI , 0.83 to 1.01 ) . Infants who received CPAP treatment , as compared with infants who received surfactant treatment , less frequently required intubation or postnatal corticosteroids for bronchopulmonary dysplasia ( P<0.001 ) , required fewer days of mechanical ventilation ( P=0.03 ) , and were more likely to be alive and free from the need for mechanical ventilation by day 7 ( P=0.01 ) . The rates of other adverse neonatal outcomes did not differ significantly between the two groups . CONCLUSIONS The results of this study support consideration of CPAP as an alternative to intubation and surfactant in preterm infants . ( Clinical Trials.gov number , NCT00233324 . Background The aim of this prospect i ve study was to determine whether a level of positive airway pressure was generated in participants receiving nasal high flow ( NHF ) delivered by the Optiflow ™ system ( Fisher and Paykel Healthcare Ltd , Auckl and , New Zeal and ) in a cardiothoracic and vascular intensive care unit ( ICU ) . Methods Nasopharyngeal airway pressure was measured in 15 postoperative cardiac surgery adult patients who received both NHF and st and ard facemask therapy  at a flow rate of 35 litre min−1 . Measurements were repeated in the open mouth and closed mouth positions . Mean airway pressure was determined by averaging the pressures at the peak of inspiration of each breath within a 1 min period , allowing the entire pressure profile of each breath to be included within the calculation . Results Low level positive pressure was demonstrated with NHF at 35 litre min−1 with mouth closed when compared with a facemask . NHF generated a mean nasopharyngeal airway pressure of mean ( sd ) 2.7 ( 1.04 ) cm H2O with the mouth closed . Airway pressure was significantly higher when breathing with mouth closed compared with mouth open ( P≤0.0001 ) . Conclusions This study demonstrated that a low level of positive pressure was generated with NHF at 35 litre min−1 of gas flow . This is consistent with results obtained in healthy volunteers . Australian Clinical Trials Registry www.actr.org.au ACT 
    Output:
    
agent
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Nasal high flow ( NHF ) has been shown to increase expiratory pressure and reduce respiratory rate but the mechanisms involved remain unclear . Ten healthy participants [ age , 22 ± 2 yr ; body mass index ( BMI ) , 24 ± 2 kg/m(2 ) ] were recruited to determine ventilatory responses to NHF of air at 37 ° C and fully saturated with water . We conducted a r and omized , controlled , cross-over study consisting of four separate ∼60-min visits , each 1 wk apart , to determine the effect of NHF on ventilation during wakefulness ( NHF at 0 , 15 , 30 , and 45 liters/min ) and sleep ( NHF at 0 , 15 , and 30 liters/min ) . In addition , a nasal cavity model was used to compare pressure/air-flow relationships of NHF and continuous positive airway pressure ( CPAP ) throughout simulated breathing . During wakefulness , NHF led to an increase in tidal volume from 0.7 ± 0.1 liter to 0.8 ± 0.2 , 1.0 ± 0.2 , and 1.3 ± 0.2 liters , and a reduction in respiratory rate ( fR ) from 16 ± 2 to 13 ± 3 , 10 ± 3 , and 8 ± 3 breaths/min ( baseline to 15 , 30 , and 45 liters/min NHF , respectively ; P < 0.01 ) . In contrast , during sleep , NHF led to a ∼20 % fall in minute ventilation due to a decrease in tidal volume and no change in fR. In the nasal cavity model , NHF increased expiratory but decreased inspiratory resistance depending on both the cannula size and the expiratory flow rate . The mechanisms of action for NHF differ from those of CPAP and are sleep/wake-state dependent . NHF may be utilized to increase tidal breathing during wakefulness and to relieve respiratory loads during sleep Objective To determine survival and neonatal morbidity for babies born between 22 and 26 weeks ’ gestation in Engl and during 2006 , and to evaluate changes in outcome since 1995 for babies born between 22 and 25 weeks ’ gestation . Design Prospect i ve national cohort studies . Setting Maternity and neonatal units in Engl and . Participants 3133 births between 22 and 26 weeks ’ gestation in 2006 ; 666 admissions to neonatal units in 1995 and 1115 in 2006 of babies born between 22 and 25 weeks ’ gestation . Main outcome measures Survival to discharge from hospital , pregnancy and delivery outcomes , infant morbidity until discharge . Results In 2006 , survival of live born babies was 2 % ( n=3 ) for those born at 22 weeks ’ gestation , 19 % ( n=66 ) at 23 weeks , 40 % ( n=178 ) at 24 weeks , 66 % ( n=346 ) at 25 weeks , and 77 % ( n=448 ) at 26 weeks ( P<0.001 ) . At discharge from hospital , 68 % ( n=705 ) of survivors had bronchopulmonary dysplasia ( receiving supplemental oxygen at 36 weeks postmenstrual age ) , 13 % ( n=135 ) had evidence of serious abnormality on cerebral ultrasonography , and 16 % ( n=166 ) had laser treatment for retinopathy of prematurity . For babies born between 22 and 25 weeks ’ gestation from March to December , the number of admissions for neonatal care increased by 44 % , from 666 in 1995 to 959 in 2006 . By 2006 adherence to evidence based practice associated with improved outcome had significantly increased . Survival increased from 40 % to 53 % ( P<0.001 ) overall and at each week of gestation : by 9.5 % ( confidence interval −0.1 % to 19 % ) at 23 weeks , 12 % ( 4 % to 20 % ) at 24 weeks , and 16 % ( 9 % to 23 % ) at 25 weeks . The proportions of babies surviving in 2006 with bronchopulmonary dysplasia , major cerebral scan abnormality , or weight and /or head circumference < −2 SD were similar to those in 1995 , but the proportion treated for retinopathy of prematurity had increased from 13 % to 22 % ( P=0.006 ) . Predictors of mortality and morbidity were similar in both cohorts . Conclusion Survival of babies born between 22 and 25 weeks ’ gestation has increased since 1995 but the pattern of major neonatal morbidity and the proportion of survivors affected are unchanged . These observations reflect an important increase in the number of preterm survivors at risk of later health problems Objective : To compare the work of breathing ( WOB ) in premature neonates supported with high-flow nasal cannula ( HFNC ) and nasal continuous positive airway pressure ( NCPAP ) . Study Design : Eighteen preterm neonates < 2.0 kg on HFNC or NCPAP support were studied in a r and om order . A ventilator was used to deliver 6 cm H2O of NCPAP with nasal prongs . High-flow nasal cannula delivered with Vapotherm ( VAPO ) at 3 , 4 and 5 l/min was used . Tidal ventilation was obtained using respiratory inductance plethysmography calibrated with face-mask pneumotachography . An esophageal balloon estimated pleural pressure from which changes in end distending pressure were calculated . Inspiratory , elastic and resistive WOB and respiratory parameters were calculated . Results : No differences were found in the WOB for all setting s. Changes in end distending pressure did not vary significantly over all device setting s except VAPO at 5 l/min . Conclusion : In these preterm infants with mild respiratory illness , HFNC provided support comparable to NCPAP OBJECTIVE To determine the better approach for weaning preterm infants from nasal continuous positive airway pressure ( NCPAP ) with or without transitioning to nasal cannula ( NC ) .  DESIGN / METHODS This is a r and omized , open label , controlled trial . Preterm infants born at ≥28 weeks gestation who were clinical ly stable on NCPAP of 5 cm H(2)O with FiO(2)<0.30 for at least 24 h were r and omly assigned to one of 2 groups . The no-NC group were kept on NCPAP until they were on FiO(2)=0.21 for 24 h , and then were weaned off NCPAP completely without any exposure to NC . If they met failing criteria , NCPAP was re-instituted . The NC-group was weaned off NCPAP when FiO(2 ) was ≤0.30 to NC ( 2 L/min ) followed by gradual weaning from oxygen . Infants who failed NC were supported back with NCPAP for 24 h before making a second attempt of NC . RESULTS Sixty neonates were enrolled ; 30 in each group . The two groups were similar in birthweight , gestational age , sex , antenatal steroids , mode of delivery , use of surfactant and xanthines , and duration of mechanical ventilation . After r and omization , the no-NC group had fewer days on oxygen [ median ( interquartile range ) : 5 ( 1 - 8 ) vs 14 ( 7.5 - 19.25 ) days , p<0.001 ] and shorter duration of respiratory support [ 10.5 ( 4 - 21 ) vs 18 ( 11.5 - 29 ) days , p=0.03 ] . There were no differences between groups regarding success of weaning  from NCPAP . CONCLUSIONS Weaning preterm infants  from NCPAP to NC is associated with increased exposure to oxygen and longer duration of respiratory support Objective To compare patient comfort in preterm infants treated with heated humidified high flow nasal cannulae ( HHHFNC )  versus nasal continuous positive airway pressure ( NCPAP ) . Design R and omised cross-over trial ( 2 × 24 h ) . Setting Single tertiary neonatal unit . Patients 20 infants less than 34 weeks postmenstrual age treated with NCPAP due to mild respiratory illness . Interventions After parental consent , infants were r and omised to 24 h of treatment with NCPAP or HHHFNC followed by 24 h of the alternate therapy . Main outcome measures Primary outcome was patient comfort assessed by the EDIN ( neonatal pain and discomfort ) scale . Secondary outcomes were respiratory parameters ( respiratory rate , FiO2 , SpO2 , TcPCO2 ) , ambient noise , salivary cortisol and parental assessment s of their child . Results We found no differences between HHHFNC and NCPAP  in mean cumulative EDIN score ( 10.7 vs 11.1 , p=0.25 ) or ambient noise ( 70 vs 74 dBa , p=0.18 ) . Parents assessed HHHFNC treatment as significantly better in the three domains , 1 ) child satisfied , 2 ) parental contact and interaction and 3 ) possibility to take part in care . Mean respiratory rate over 24 h was lower during HHHFNC than CPAP ( 41 vs 46 , p=0.001 ) . Other respiratory parameters were similar . Conclusions Using EDIN scale , we found no difference in patient comfort with HHHFNC versus NCPAP . However , parents preferred HHHFNC , and during HHHFNC respiratory rate was lower than during NCPAP . Clinical Trials.gov , number NCT01526226 BACKGROUND There are limited data to inform the choice between early treatment with continuous positive airway pressure ( CPAP ) and early surfactant treatment as the initial support for extremely-low-birth-weight infants . METHODS We performed a r and omized , multicenter trial , with a 2-by-2 factorial design , involving infants who were born between 24 weeks 0 days and 27 weeks 6 days of gestation . Infants were r and omly assigned to intubation and surfactant treatment ( within 1 hour after birth ) or to CPAP treatment initiated in the delivery room , with subsequent use of a protocol -driven limited ventilation strategy . Infants were also r and omly assigned to one of two target ranges of oxygen saturation . The primary outcome was death or bronchopulmonary dysplasia as defined by the requirement for supplemental oxygen at 36 weeks ( with an attempt at withdrawal of supplemental oxygen in neonates who were receiving less than 30 % oxygen ) . RESULTS A total of 1316 infants were enrolled in the study . The rates of the primary outcome did not differ significantly between the CPAP group and the surfactant group ( 47.8 % and 51.0 % , respectively ; relative risk with CPAP , 0.95 ; 95 % confidence interval [ CI ] , 0.85 to 1.05 ) after adjustment for gestational age , center , and familial clustering . The results were similar when bronchopulmonary dysplasia was defined according to the need for any supplemental oxygen at 36 weeks ( rates of primary outcome , 48.7 % and 54.1 % , respectively ; relative risk with CPAP , 0.91 ; 95 % CI , 0.83 to 1.01 ) . Infants who received CPAP treatment , as compared with infants who received surfactant treatment , less frequently required intubation or postnatal corticosteroids for bronchopulmonary dysplasia ( P<0.001 ) , required fewer days of mechanical ventilation ( P=0.03 ) , and were more likely to be alive and free from the need for mechanical ventilation by day 7 ( P=0.01 ) . The rates of other adverse neonatal outcomes did not differ significantly between the two groups . CONCLUSIONS The results of this study support consideration of CPAP as an alternative to intubation and surfactant in preterm infants . ( Clinical Trials.gov number , NCT00233324 . Background The aim of this prospect i ve study was to determine whether a level of positive airway pressure was generated in participants receiving nasal high flow ( NHF ) delivered by the Optiflow ™ system ( Fisher and Paykel Healthcare Ltd , Auckl and , New Zeal and ) in a cardiothoracic and vascular intensive care unit ( ICU ) . Methods Nasopharyngeal airway pressure was measured in 15 postoperative cardiac surgery adult patients who received both NHF and st and ard facemask therapy  at a flow rate of 35 litre min−1 . Measurements were repeated in the open mouth and closed mouth positions . Mean airway pressure was determined by averaging the pressures at the peak of inspiration of each breath within a 1 min period , allowing the entire pressure profile of each breath to be included within the calculation . Results Low level positive pressure was demonstrated with NHF at 35 litre min−1 with mouth closed when compared with a facemask . NHF generated a mean nasopharyngeal airway pressure of mean ( sd ) 2.7 ( 1.04 ) cm H2O with the mouth closed . Airway pressure was significantly higher when breathing with mouth closed compared with mouth open ( P≤0.0001 ) . Conclusions This study demonstrated that a low level of positive pressure was generated with NHF at 35 litre min−1 of gas flow . This is consistent with results obtained in healthy volunteers . Australian Clinical Trials Registry www.actr.org.au ACT 
    Output:
    