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: Objective To compare the physiological effects and the clinical efficacy of continuous positive airway pressure ( CPAP ) vs st and ard medical treatment in elderly patients ( ≥75 years ) with acute hypoxemic respiratory failure related to cardiogenic pulmonary edema . Design A prospect i ve , r and omized , concealed , and unblinded study of 89 consecutive patients who were admitted to the emergency departments of one general , and three teaching , hospitals . Intervention Patients were r and omly assigned to receive st and ard medical treatment alone ( n=46 ) or st and ard medical treatment plus CPAP ( n=43 ) . Measurements Improvement in PaO2/FIO2 ratio , complications , length of hospital stay , early 48-h and overall mortality , compared between the CPAP and st and ard treatment groups . Results Study groups were comparable with regard to baseline physiological and clinical characteristics ( age , sex ratio , autonomy , medical history , cause of pulmonary edema ) . Within 1 h , noninvasive continuous positive airway pressure led to decreased respiratory rate ( respiratory rate , 27±7 vs 35±6 breaths/min ; p=0.009 ) , and improved oxygenation ( PaO2/FIO2 , 306±104 vs 157±71 ; p=0.004 ) compared with baseline , whereas no differences were observed within the st and ard treatment group . Severe complications occurred in 17 patients in the st and ard treatment group , vs 4 patients in the noninvasive continuous positive airway pressure group ( p=0.002 ) . Early 48-h mortality was 7 % in the noninvasive continuous positive airway pressure group , compared with 24 % in the st and ard treatment group ( p=0.017 ) ; however , no sustained benefits were observed during the overall hospital stay . Conclusion Noninvasive continuous positive airway pressure promotes early clinical improvement in elderly patients attending emergency departments for a severe pulmonary edema , but only reduces early 48-h mortality OBJECTIVE To evaluate the utility of bilevel positive airway pressure ( BiPAP ) in the out-of-hospital treatment of patients with presumed congestive heart failure ( CHF ) . METHODS This was a prospect i ve , sequential , parallel trial in an urban setting served by a single emergency medical services ( EMS ) system between January 4 and April 15 , 1999 . A convenience sampling of adults who were transported by rescue units judged to be in CHF by treating emergency medical technicians trained in advanced life support ( ALS EMTs ) was included . Rescue squads were divided into demographically matched pairs , and one of each was equipped with a BiPAP ventilatory support unit . Bilevel positive airway pressure therapy was added to the existing treatment protocol s for eligible study patients . Main outcome measures were out-of-hospital treatment time , oxygen saturation changes , hospitalization length , need for endotracheal intubation , mortality rate , and ease of use of the device by EMS personnel . RESULTS Sixty-two of 71 enrolled patients completed the study .  Out-of-hospital treatment times did not differ between groups ( 31.2 minutes vs 31.4 minutes ; p = 0.931 ) . The difference between pre- and post-treatment oxygen saturation levels was greater for the BiPAP group ( 13.71 % ) than the control group ( 6.69 % ) ( p < 0.05 ) . There was no statistical difference between groups in the length of hospital stay [ control : 7.63 days , vs BiPAP : 6.33 days , p = 0.48 ] , the intubation rate [ control : 7 of 25 ( 28 % ) vs BiPAP : 4 of 37 ( 11 % ) , p = 0.10 ] , or death rate [ control : 2 of 24 , vs BiPAP : 6 of 37 , p = 0.46 ] . All of the ALS EMTs who used BiPAP thought that it was safe to use , and 97 % thought it was easy and appeared to improve patients ' dyspnea and respiratory distress . CONCLUSIONS ALS EMTs can be trained to deliver noninvasive ventilation with BiPAP , find it easy to apply , and believe that it helps relieve dyspnea in patients with suspected CHF OBJECTIVE To evaluate whether bilevel positive airway pressure , by actively assisting inhalation , more rapidly improves ventilation , acidemia , and dyspnea than continuous positive airway pressure ( CPAP ) in patients with acute pulmonary edema . DESIGN R and omized , controlled , double-blind trial . SETTING Emergency department in a university hospital . PATIENTS Twenty-seven patients , presenting with acute pulmonary edema , characterized by dyspnea , tachypnea , tachycardia , accessory muscle use , bilateral rales , and typical findings of congestion on a chest radiograph . INTERVENTIONS In addition to st and ard therapy , 13 patients were r and omized to receive nasal CPAP ( 10 cm H2O ) , and 14 patients were r and omized to receive nasal bilevel positive airway pressure ( inspiratory and expiratory positive airway pressures of 15 and 5 cm H2O , respectively ) in the spontaneous/timed mode that combines patient flow-triggering and backup time-triggering . MEASUREMENTS AND MAIN RESULTS After 30 mins , significant reductions in breathing frequency ( 32 + /- 4 to 26 + /- 5 breaths/min ) , heart rate ( 110 + /- 21 to 97 + /- 20 beats/min ) , blood pressure ( mean 117 + /- 28 to 92 + /- 18 mm Hg ) , and Paco2 ( 56 + /- 15 to 43 + /- 9 torr [ 7.5 + /- 2 to 5.7 + /- 1.2 kPa ] ) were observed in the bilevel positive airway pressure group , as were significant improvements in arterial pH and dyspnea scores ( p < .05 for all of these parameters ) . Only breathing frequency improved significantly in the CPAP group ( 32 + /- 4 to 28 + /- 5 breaths/min , p < .05 ) . At 30 mins ; the bilevel positive airway pressure group had greater reductions in Paco2 ( p = .057 ) , systolic blood pressure ( p = .005 ) , and mean arterial pressure ( p = .03 ) than the CPAP group . The myocardial infa rct ion rate was higher in the bilevel positive airway pressure group ( 71 % ) compared with both the CPAP group ( 31 % ) and historically matched controls ( 38 % ) ( p = .05 ) . Duration of ventilator use , intensive care unit and hospital stays , and intubation and mortality rates were similar between the two groups . CONCLUSIONS Bilevel positive airway pressure improves ventilation and vital signs more rapidly than CPAP in patients with acute pulmonary edema . The higher  rate  of myocardial infa rct ions associated with the use of bilevel positive airway pressure highlights the need for further studies to clarify its effects on hemodynamics and infa rct ion rates , and to determine optimal pressure setting Objective Continuous positive airway pressure ( CPAP ) is considered an effective nonpharmacologic method of treating patients with severe acute cardiogenic pulmonary edema . However , we hypothesized that bilevel noninvasive positive-pressure ventilation ( NPPV ) , which combines both inspiratory pressure support and positive expiratory pressure , would unload the respiratory muscles and improve cardiac and hemodynamic function more effectively than CPAP . Design R and omized crossover study . Setting Critical care unit , Raymond Poincaré Hospital . Patients Six consecutive patients with acute cardiogenic pulmonary edema . Interventions Patients were sequentially treated with 5 cm H2O CPAP , 10 cm H2O CPAP , and NPPV in a r and om order . Measurements and Main Results Cardiac and hemodynamic function and indexes of respiratory mechanics were measured at each treatment sequence . NPPV reduced the esophageal pressure swing and esophageal pressure-time product compared with baseline ( p < .05 ) . There was no reduction in esophageal pressure swing or esophageal pressure-time product with CPAP . NPPV and 10 cm H2O CPAP reduced the mean transmural right and left atrial filling pressures without a change in cardiac index . Conclusions This study demonstrates that NPPV was more effective at unloading the respiratory muscles than CPAP in acute cardiogenic pulmonary edema . In addition , NPPV and 10 cm H2O CPAP produced a reduction in right and left ventricular preload , which suggests an improvement in cardiac performance Objective This study compared noninvasive pressure support ventilation ( NIPSV ) and continuous positive airway pressure ( CPAP ) in patients with acute hypercapnic pulmonary edema with regard to resolution time . Design and setting R and omized prospect i ve study in an emergency department . Patients and participants We r and omly assigned 36 patients with respiratory failure due to acute pulmonary edema and arterial hypercapnia ( PaCO2 > 45 mmHg ) to NIPSV ( n=18 ) or CPAP through a face mask ( n=18 ) . Measurements and results Electrocardiographic and physiological measurements were made over 36 h. There was no difference in resolution time defined as clinical improvement with a respiratory rate of fewer than 30 breaths/min and SpO2 of 96 % or more between CPAP and NIPSV groups . Arterial carbon dioxide tension was significantly decreased after 1 h of ventilation ( CPAP , 60.5±13.6 to 42.8±4.9 mmHg ; NIPSV , 65.7±13.6 to 44.0±5.5 mmHg ) ; respective improvements were seen in pH ( CPAP , 7.22±0.11 to 7.37±0.04 ; NIPSV , 7.19±0.11 to 7.38±0.04 ) , SpO2 ( CPAP , 86.9±3.7 % to 95.1±2.6 % ; NIPSV , 83.7±6.6 % to 96.0±2.9 % ) , and respiratory rate ( CPAP , 37.9±4.5 to 21.3±5.1 breaths/min ; NIPSV , 39.8±4.4 to 21.2±4.6 breaths/min ) . No significant differences were seen with regards to endotracheal intubation and in-hospital mortality . Conclusions NIPSV proved as effective as CPAP in the treatment of patients with acute pulmonary edema and hypercapnia but did not improve resolution time The efficacy of continuous positive airway pressure ( CPAP ) administered with a face mask was compared to oxygen supplementation in 40 patients with acute cardiogenic pulmonary edema . Baseline arterial blood gas values and pH , heart rate , respiratory rate , and blood pressure were recorded after patients breathed 28 percent oxygen with an ambient airway pressure for ten minutes . Thereafter , inspired oxygen concentration ( FIO2 ) was increased by 0.10 and airway pressure was increased by 10 cm H2O in r and om sequence . Cardiopulmonary function was reassessed after a five-minute stabilization period at each level of oxygen supplementation and airway pressure . An increase in FIO2 and the application of CPAP both produced significant elevation in arterial blood oxygen tension . Use of CPAP was consistently associated with a decrease in respiratory rate , blood pressure , and rate pressure product , which were not observed with a mere enhancement of oxygen therapy . The improvement in the measured cardiopulmonary variables associated with CPAP therapy can not be achieved by reversing hypoxemia with supplemental oxygen only Objectives : To assess ( 1 ) the short-term hemodynamic , respiratory and arterial blood gas effects of NIPSV in patients with ACPE who were likely to require endotracheal intubation , ( 2 ) the initial causes of failure and ( 3 ) the side effects and the difficulties of this technique . Design : Uncontrolled , prospect i ve clinical study . Setting : Teaching hospital intensive care unit . Patients : 26 consecutive patients with severe ACPE . Interventions : Noninvasive ventilation via a face mask , using a pressure support mode ( 20.5 ± 4.7 cmH2O ) , with an initial fractional inspired oxygen of 93.0 ± 16 % and a positive end-expiratory pressure of 3.5 ± 2.3 cmH2O . The need to intubate the patients within 48 h was considered as a criterion of failure of the procedure . Measurements and results : Clinical and biological parameters were measured at 15 and 30 minutes , 1 h and 2 h and at 1 h and 2 h , respectively . There were 5 ( 21 % ) failures and 21 ( 79 % ) successes . In both the success and the failure groups , clinical and blood gas parameters improved at the first measure . In the success group , within 15 min of the start of NIPSV , pulse oximetry saturation ( SpO2 ) had increased from 84 ± 12 to 96 ± 4 % ( p < 0.001 ) , the respiratory rate ( RR ) had decreased from 36 ± 5.3 to 22.4 ± 4.9 breaths/min ( p < 0.0001 ) and within 1 h the arterial oxygen tension and pH , respectively , had increased from 61 ± 14 to 270 ± 126 mmHg ( p < 0.0001 ) and from 7.25 ± 0. 
    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: Objective To compare the physiological effects and the clinical efficacy of continuous positive airway pressure ( CPAP ) vs st and ard medical treatment in elderly patients ( ≥75 years ) with acute hypoxemic respiratory failure related to cardiogenic pulmonary edema . Design A prospect i ve , r and omized , concealed , and unblinded study of 89 consecutive patients who were admitted to the emergency departments of one general , and three teaching , hospitals . Intervention Patients were r and omly assigned to receive st and ard medical treatment alone ( n=46 ) or st and ard medical treatment plus CPAP ( n=43 ) . Measurements Improvement in PaO2/FIO2 ratio , complications , length of hospital stay , early 48-h and overall mortality , compared between the CPAP and st and ard treatment groups . Results Study groups were comparable with regard to baseline physiological and clinical characteristics ( age , sex ratio , autonomy , medical history , cause of pulmonary edema ) . Within 1 h , noninvasive continuous positive airway pressure led to decreased respiratory rate ( respiratory rate , 27±7 vs 35±6 breaths/min ; p=0.009 ) , and improved oxygenation ( PaO2/FIO2 , 306±104 vs 157±71 ; p=0.004 ) compared with baseline , whereas no differences were observed within the st and ard treatment group . Severe complications occurred in 17 patients in the st and ard treatment group , vs 4 patients in the noninvasive continuous positive airway pressure group ( p=0.002 ) . Early 48-h mortality was 7 % in the noninvasive continuous positive airway pressure group , compared with 24 % in the st and ard treatment group ( p=0.017 ) ; however , no sustained benefits were observed during the overall hospital stay . Conclusion Noninvasive continuous positive airway pressure promotes early clinical improvement in elderly patients attending emergency departments for a severe pulmonary edema , but only reduces early 48-h mortality OBJECTIVE To evaluate the utility of bilevel positive airway pressure ( BiPAP ) in the out-of-hospital treatment of patients with presumed congestive heart failure ( CHF ) . METHODS This was a prospect i ve , sequential , parallel trial in an urban setting served by a single emergency medical services ( EMS ) system between January 4 and April 15 , 1999 . A convenience sampling of adults who were transported by rescue units judged to be in CHF by treating emergency medical technicians trained in advanced life support ( ALS EMTs ) was included . Rescue squads were divided into demographically matched pairs , and one of each was equipped with a BiPAP ventilatory support unit . Bilevel positive airway pressure therapy was added to the existing treatment protocol s for eligible study patients . Main outcome measures were out-of-hospital treatment time , oxygen saturation changes , hospitalization length , need for endotracheal intubation , mortality rate , and ease of use of the device by EMS personnel . RESULTS Sixty-two of 71 enrolled patients completed the study .  Out-of-hospital treatment times did not differ between groups ( 31.2 minutes vs 31.4 minutes ; p = 0.931 ) . The difference between pre- and post-treatment oxygen saturation levels was greater for the BiPAP group ( 13.71 % ) than the control group ( 6.69 % ) ( p < 0.05 ) . There was no statistical difference between groups in the length of hospital stay [ control : 7.63 days , vs BiPAP : 6.33 days , p = 0.48 ] , the intubation rate [ control : 7 of 25 ( 28 % ) vs BiPAP : 4 of 37 ( 11 % ) , p = 0.10 ] , or death rate [ control : 2 of 24 , vs BiPAP : 6 of 37 , p = 0.46 ] . All of the ALS EMTs who used BiPAP thought that it was safe to use , and 97 % thought it was easy and appeared to improve patients ' dyspnea and respiratory distress . CONCLUSIONS ALS EMTs can be trained to deliver noninvasive ventilation with BiPAP , find it easy to apply , and believe that it helps relieve dyspnea in patients with suspected CHF OBJECTIVE To evaluate whether bilevel positive airway pressure , by actively assisting inhalation , more rapidly improves ventilation , acidemia , and dyspnea than continuous positive airway pressure ( CPAP ) in patients with acute pulmonary edema . DESIGN R and omized , controlled , double-blind trial . SETTING Emergency department in a university hospital . PATIENTS Twenty-seven patients , presenting with acute pulmonary edema , characterized by dyspnea , tachypnea , tachycardia , accessory muscle use , bilateral rales , and typical findings of congestion on a chest radiograph . INTERVENTIONS In addition to st and ard therapy , 13 patients were r and omized to receive nasal CPAP ( 10 cm H2O ) , and 14 patients were r and omized to receive nasal bilevel positive airway pressure ( inspiratory and expiratory positive airway pressures of 15 and 5 cm H2O , respectively ) in the spontaneous/timed mode that combines patient flow-triggering and backup time-triggering . MEASUREMENTS AND MAIN RESULTS After 30 mins , significant reductions in breathing frequency ( 32 + /- 4 to 26 + /- 5 breaths/min ) , heart rate ( 110 + /- 21 to 97 + /- 20 beats/min ) , blood pressure ( mean 117 + /- 28 to 92 + /- 18 mm Hg ) , and Paco2 ( 56 + /- 15 to 43 + /- 9 torr [ 7.5 + /- 2 to 5.7 + /- 1.2 kPa ] ) were observed in the bilevel positive airway pressure group , as were significant improvements in arterial pH and dyspnea scores ( p < .05 for all of these parameters ) . Only breathing frequency improved significantly in the CPAP group ( 32 + /- 4 to 28 + /- 5 breaths/min , p < .05 ) . At 30 mins ; the bilevel positive airway pressure group had greater reductions in Paco2 ( p = .057 ) , systolic blood pressure ( p = .005 ) , and mean arterial pressure ( p = .03 ) than the CPAP group . The myocardial infa rct ion rate was higher in the bilevel positive airway pressure group ( 71 % ) compared with both the CPAP group ( 31 % ) and historically matched controls ( 38 % ) ( p = .05 ) . Duration of ventilator use , intensive care unit and hospital stays , and intubation and mortality rates were similar between the two groups . CONCLUSIONS Bilevel positive airway pressure improves ventilation and vital signs more rapidly than CPAP in patients with acute pulmonary edema . The higher  rate  of myocardial infa rct ions associated with the use of bilevel positive airway pressure highlights the need for further studies to clarify its effects on hemodynamics and infa rct ion rates , and to determine optimal pressure setting Objective Continuous positive airway pressure ( CPAP ) is considered an effective nonpharmacologic method of treating patients with severe acute cardiogenic pulmonary edema . However , we hypothesized that bilevel noninvasive positive-pressure ventilation ( NPPV ) , which combines both inspiratory pressure support and positive expiratory pressure , would unload the respiratory muscles and improve cardiac and hemodynamic function more effectively than CPAP . Design R and omized crossover study . Setting Critical care unit , Raymond Poincaré Hospital . Patients Six consecutive patients with acute cardiogenic pulmonary edema . Interventions Patients were sequentially treated with 5 cm H2O CPAP , 10 cm H2O CPAP , and NPPV in a r and om order . Measurements and Main Results Cardiac and hemodynamic function and indexes of respiratory mechanics were measured at each treatment sequence . NPPV reduced the esophageal pressure swing and esophageal pressure-time product compared with baseline ( p < .05 ) . There was no reduction in esophageal pressure swing or esophageal pressure-time product with CPAP . NPPV and 10 cm H2O CPAP reduced the mean transmural right and left atrial filling pressures without a change in cardiac index . Conclusions This study demonstrates that NPPV was more effective at unloading the respiratory muscles than CPAP in acute cardiogenic pulmonary edema . In addition , NPPV and 10 cm H2O CPAP produced a reduction in right and left ventricular preload , which suggests an improvement in cardiac performance Objective This study compared noninvasive pressure support ventilation ( NIPSV ) and continuous positive airway pressure ( CPAP ) in patients with acute hypercapnic pulmonary edema with regard to resolution time . Design and setting R and omized prospect i ve study in an emergency department . Patients and participants We r and omly assigned 36 patients with respiratory failure due to acute pulmonary edema and arterial hypercapnia ( PaCO2 > 45 mmHg ) to NIPSV ( n=18 ) or CPAP through a face mask ( n=18 ) . Measurements and results Electrocardiographic and physiological measurements were made over 36 h. There was no difference in resolution time defined as clinical improvement with a respiratory rate of fewer than 30 breaths/min and SpO2 of 96 % or more between CPAP and NIPSV groups . Arterial carbon dioxide tension was significantly decreased after 1 h of ventilation ( CPAP , 60.5±13.6 to 42.8±4.9 mmHg ; NIPSV , 65.7±13.6 to 44.0±5.5 mmHg ) ; respective improvements were seen in pH ( CPAP , 7.22±0.11 to 7.37±0.04 ; NIPSV , 7.19±0.11 to 7.38±0.04 ) , SpO2 ( CPAP , 86.9±3.7 % to 95.1±2.6 % ; NIPSV , 83.7±6.6 % to 96.0±2.9 % ) , and respiratory rate ( CPAP , 37.9±4.5 to 21.3±5.1 breaths/min ; NIPSV , 39.8±4.4 to 21.2±4.6 breaths/min ) . No significant differences were seen with regards to endotracheal intubation and in-hospital mortality . Conclusions NIPSV proved as effective as CPAP in the treatment of patients with acute pulmonary edema and hypercapnia but did not improve resolution time The efficacy of continuous positive airway pressure ( CPAP ) administered with a face mask was compared to oxygen supplementation in 40 patients with acute cardiogenic pulmonary edema . Baseline arterial blood gas values and pH , heart rate , respiratory rate , and blood pressure were recorded after patients breathed 28 percent oxygen with an ambient airway pressure for ten minutes . Thereafter , inspired oxygen concentration ( FIO2 ) was increased by 0.10 and airway pressure was increased by 10 cm H2O in r and om sequence . Cardiopulmonary function was reassessed after a five-minute stabilization period at each level of oxygen supplementation and airway pressure . An increase in FIO2 and the application of CPAP both produced significant elevation in arterial blood oxygen tension . Use of CPAP was consistently associated with a decrease in respiratory rate , blood pressure , and rate pressure product , which were not observed with a mere enhancement of oxygen therapy . The improvement in the measured cardiopulmonary variables associated with CPAP therapy can not be achieved by reversing hypoxemia with supplemental oxygen only Objectives : To assess ( 1 ) the short-term hemodynamic , respiratory and arterial blood gas effects of NIPSV in patients with ACPE who were likely to require endotracheal intubation , ( 2 ) the initial causes of failure and ( 3 ) the side effects and the difficulties of this technique . Design : Uncontrolled , prospect i ve clinical study . Setting : Teaching hospital intensive care unit . Patients : 26 consecutive patients with severe ACPE . Interventions : Noninvasive ventilation via a face mask , using a pressure support mode ( 20.5 ± 4.7 cmH2O ) , with an initial fractional inspired oxygen of 93.0 ± 16 % and a positive end-expiratory pressure of 3.5 ± 2.3 cmH2O . The need to intubate the patients within 48 h was considered as a criterion of failure of the procedure . Measurements and results : Clinical and biological parameters were measured at 15 and 30 minutes , 1 h and 2 h and at 1 h and 2 h , respectively . There were 5 ( 21 % ) failures and 21 ( 79 % ) successes . In both the success and the failure groups , clinical and blood gas parameters improved at the first measure . In the success group , within 15 min of the start of NIPSV , pulse oximetry saturation ( SpO2 ) had increased from 84 ± 12 to 96 ± 4 % ( p < 0.001 ) , the respiratory rate ( RR ) had decreased from 36 ± 5.3 to 22.4 ± 4.9 breaths/min ( p < 0.0001 ) and within 1 h the arterial oxygen tension and pH , respectively , had increased from 61 ± 14 to 270 ± 126 mmHg ( p < 0.0001 ) and from 7.25 ± 0. 
    Output:
    