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: CONTEXT Continuous positive airway pressure ( CPAP ) is widely used in the belief that it may reduce the need for intubation and mechanical ventilation in patients with acute hypoxemic respiratory insufficiency . OBJECTIVE To compare the physiologic effects and the clinical efficacy of CPAP vs st and ard oxygen therapy in patients with acute hypoxemic , nonhypercapnic respiratory insufficiency . DESIGN , SETTING , AND PATIENTS R and omized , concealed , and unblinded trial of 123 consecutive adult patients who were admitted to 6 intensive care units between September 1997 and January 1999 with a PaO(2)/FIO(2 ) ratio of 300 mm Hg or less due to bilateral pulmonary edema ( n = 102 with acute lung injury and n = 21 with cardiac disease ) . INTERVENTIONS Patients were r and omly assigned to receive oxygen therapy alone ( n = 61 ) or oxygen therapy plus CPAP ( n = 62 ) . MAIN OUTCOME MEASURES Improvement in PaO(2)/FIO(2 ) ratio , rate of endotracheal intubation at any time during the study , adverse events , length of hospital stay , mortality , and duration of ventilatory assistance , compared between the CPAP and st and ard treatment groups . RESULTS Among the CPAP vs st and ard therapy groups , respectively , causes of respiratory failure ( pneumonia , 54 % and 55 % ) , presence of cardiac disease ( 33 % and 35 % ) , severity at admission , and hypoxemia ( median [ 5th-95th percentile ] PaO(2)/FIO(2 ) ratio , 140 [ 59 - 288 ] mm Hg vs 148 [ 62 - 283 ] mm Hg ; P = .43 ) were similarly distributed . After 1 hour of treatment , subjective responses to treatment ( P<.001 ) and median ( 5th-95th percentile ) PaO(2)/FIO(2 ) ratios were greater with CPAP ( 203 [ 45 - 431 ] mm Hg vs 151 [ 73 - 482 ] mm Hg ; P = .02 ) . No further difference in respiratory indices was observed between the groups . Treatment with CPAP failed to reduce the endotracheal intubation rate ( 21 [ 34 % ] vs 24 [ 39 % ] in the st and ard therapy group ; P = .53 ) , hospital mortality ( 19 [ 31 % ] vs 18 [ 30 % ] ; P = .89 ) , or median ( 5th-95th percentile ) intensive care unit length of stay ( 6.5 [ 1 - 57 ] days vs 6.0 [ 1 - 36 ] days ; P = .43 ) . A higher number of adverse events occurred with CPAP treatment ( 18 vs 6 ; P = .01 ) . CONCLUSION In this study , despite early physiologic improvement , CPAP neither reduced the need for intubation nor improved outcomes in patients with acute hypoxemic , nonhypercapnic respiratory insufficiency primarily due to acute lung injury . JAMA . 2000;284:2352 - 2360 Objective Noninvasive ventilation ( NIV ) fails more frequently for de novo acute respiratory failure ( de novo ) than for cardiogenic pulmonary edema ( CPE ) or acute-on-chronic respiratory failure ( AOC ) . The impact of NIV failure and success was compared between de novo and CPE or AOC after adjustment for disease severity . Setting s Patients requiring ventilatory support were enrolled in a prospect i ve survey in 70 French ICUs . Of 1076 patients requiring ventilatory support , 524 were eligible , including 299 de novo ( NIV use , 30 % ) and 225 CPE-AOC ( NIV use , 55 % ) . Design and analysis Independent risk factors associated with mortality and length of stay were identified by logistic regression analysis . The adjusted outcome of NIV success or failure was compared to that with endotracheal intubation without NIV . Results  NIV success was independently associated with survival in both de novo , adjusted OR 0.05 ( 95 % CI 0.01–0.42 ) , and CPE-AOC OR 0.03 ( CI 0.01–0.24 ) . NIV failure was associated with ICU mortality in the de novo group ( OR 3.24 , CI 1.61–6.53 ) but not in the CPE-AOC group . Nosocomial pneumonia was less common in patients successful with NIV .  NIV failure was associated with a longer ICU stay in CPE-AOC only . The overall use of NIV was independently associated with a better outcome only in CPE-AOC patients ( OR 0.33 , CI 0.15–0.73 ) . Conclusion The effect of NIV differs between de novo and CPE-AOC patients because NIV failure is associated with increased mortality for de novo patients . This finding should raise a note of caution when applying NIV in this indication Introduction : The role of non-invasive positive pressure ventilation delivered through a face mask in patients with flail chest is uncertain . We conducted a prospect i ve , r and omised 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 r and omly 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 PO2 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 The prognosis of patients suffering from respiratory failure ( RF ) after allogeneic hematopoietic SCT ( HSCT ) is poor . However , early treatment for using non-invasive ventilation ( NIV ) may be of benefit . We conducted a r and omized trial to prove the impact of early NIV  in patients in the early post-transplant period . A total of 526 patients undergoing HSCT in a single center were monitored for signs of RF . Patients with RF were enrolled into either treatment arm A ( oxygen supply only ) or treatment arm B ( oxygen+intermittent NIV ) . RF had to be diagnosed in 86 patients ( 16 % ) . RF was an independent risk factor for both short-term ( 100 day mortality/ OR 2.76 ; P<0.001 ) and long-term survival ( OR 1.57 ; P<0.01 ) . Although early RF treatment with NIV was associated with a decreased rate of failure to achieve sufficient oxygenation ( 39 % in arm A vs 24 % in arm B , P=0.17 ) , neither intensive care unit admission rate , nor need for intubation or survival parameters were affected by the treatment strategy . An early interventional strategy using NIV was not associated with improvement of the prognosis of the patients . The limited influence of NIV may be related to the study design allowing for switching of treatment in case of unsatisfactory efficacy CONTEXT Noninvasive ventilation ( NIV ) has been associated with lower rates of endotracheal intubation in population s of patients with acute respiratory failure . OBJECTIVE To compare NIV with st and ard treatment using supplemental oxygen administration to avoid endotracheal intubation in recipients of solid organ transplantation with acute hypoxemic respiratory failure . DESIGN AND SETTING Prospect i ve r and omized study conducted at a 14-bed , general intensive care unit of a university hospital . PATIENTS Of 238 patients who underwent solid organ transplantation from December 1995 to October 1997 , 51 were treated for acute respiratory failure . Of these , 40 were eligible and 20 were r and omized to each group . INTERVENTION Noninvasive ventilation vs st and ard treatment with supplemental oxygen administration . MAIN OUTCOME MEASURES The need for endotracheal intubation and mechanical ventilation at any time during the study , complications not present on admission , duration of ventilatory assistance , length of hospital stay , and intensive care unit mortality . RESULTS The 2 groups were similar at study entry . Within the first hour of treatment , 14 patients ( 70 % ) in the NIV group , and 5 patients ( 25 % ) in the st and ard treatment group improved their ratio of the PaO2 to the fraction of inspired oxygen ( FIO2 ) . Over time , a sustained improvement in PaO2 to FIO2 was noted in 12 patients ( 60 % ) in the NIV group , and in 5 patients ( 25 % ) r and omized to st and ard treatment ( P = .03 ) . The use of NIV was associated with a significant reduction in the rate of endotracheal intubation ( 20 % vs 70 % ; P = .002 ) , rate of fatal complications ( 20 % vs 50 % ; P = .05 ) , length of stay in the intensive care unit by survivors ( mean [ SD ] days , 5.5 [ 3 ] vs 9 [ 4 ] ; P = .03 ) , and intensive care unit mortality ( 20 % vs 50 % ; P = .05 ) . Hospital mortality did not differ . CONCLUSIONS These results indicate that transplantation programs should consider NIV in the treatment of selected recipients of transplantation with acute respiratory failure STUDY OBJECTIVE Noninvasive mechanical ventilation ( NIMV ) is beneficial for patients with acute respiratory failure ( ARF ) when added to medical treatment . However , its role as an alternative to conventional mechanical ventilation ( CMV ) remains controversial . Our aim was to compare the efficacy and re source consumption of NIMV against CMV in patients with ARF . DESIGN A r and omized , multicenter , controlled trial . SETTING Seven multi purpose ICUs . PATIENTS Sixty-four patients with ARF from various causes who fulfilled criteria for mechanical ventilation . INTERVENTION The noninvasive group received ventilation through a face mask in pressure-support mode plus positive end-expiratory pressure ; the conventional group received ventilation through a tracheal tube . MEASUREMENTS AND RESULTS Avoidance of intubation , mortality , and consumption of re sources were the outcome variables . Thirty-one patients were assigned to the noninvasive group , and 33 were assigned to the conventional group . In the noninvasive group , 58 % patients were intubated , vs 100 % in the conventional group ( relative risk reduction , 43 % ; p < 0.001 ) . Stratification by type of ARF gave similar results . In the ICU , death occurred in 23 % and 39 % ( p = 0.09 ) and complications occurred in 52 % and 70 % ( p = 0.07 ) in the noninvasive and conventional groups , respectively . There were no differences in length of stay . The Therapeutic Intervention Score System-28 , but not the direct nursing activity time , was lower in the noninvasive group during the first 3 days . CONCLUSIONS NIMV reduces the need for intubation and therapeutic intervention in patients with ARF from different causes . There is a nonsignificant trend of reduction in ICUs and hospital mortality together with fewer complications during ICU stay Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more BACKGROUND Noninvasive ventilation ( NIV ) is an emerging modality in the management of patients with acute respiratory failure . However , its role in severe acute asthma is not well defined . OBJECTIVE Evaluate the efficacy of NIV in severe acute asthma . METHODS Patients with severe acute asthma were r and omized to receive either st and ard medical therapy or NIV in addition to medical therapy . The primary outcomes were improvement in forced expiratory volume in the first second ( FEV1 ) , intensive care unit ( ICU ) stay , and hospital stay . The secondary outcomes were rate of improvement in respiratory rate , blood pH , ratio of PaO2 to fraction of inspired oxygen ( F(I)O2 ) , PaCO2 , requirement for inhaled medications , and failure of primary therapy . RESULTS Fifty-three patients with severe acute asthma ( 42 females and 11 males , mean + /- SD age 44 + /- 15 y , FEV1 < 30 % of predicted ) were r and omized to NIV ( n = 28 ) or st and ard medical therapy ( n = 25 ) . The baseline variables were similar in the 2 groups except for the mean duration of ast 
    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: CONTEXT Continuous positive airway pressure ( CPAP ) is widely used in the belief that it may reduce the need for intubation and mechanical ventilation in patients with acute hypoxemic respiratory insufficiency . OBJECTIVE To compare the physiologic effects and the clinical efficacy of CPAP vs st and ard oxygen therapy in patients with acute hypoxemic , nonhypercapnic respiratory insufficiency . DESIGN , SETTING , AND PATIENTS R and omized , concealed , and unblinded trial of 123 consecutive adult patients who were admitted to 6 intensive care units between September 1997 and January 1999 with a PaO(2)/FIO(2 ) ratio of 300 mm Hg or less due to bilateral pulmonary edema ( n = 102 with acute lung injury and n = 21 with cardiac disease ) . INTERVENTIONS Patients were r and omly assigned to receive oxygen therapy alone ( n = 61 ) or oxygen therapy plus CPAP ( n = 62 ) . MAIN OUTCOME MEASURES Improvement in PaO(2)/FIO(2 ) ratio , rate of endotracheal intubation at any time during the study , adverse events , length of hospital stay , mortality , and duration of ventilatory assistance , compared between the CPAP and st and ard treatment groups . RESULTS Among the CPAP vs st and ard therapy groups , respectively , causes of respiratory failure ( pneumonia , 54 % and 55 % ) , presence of cardiac disease ( 33 % and 35 % ) , severity at admission , and hypoxemia ( median [ 5th-95th percentile ] PaO(2)/FIO(2 ) ratio , 140 [ 59 - 288 ] mm Hg vs 148 [ 62 - 283 ] mm Hg ; P = .43 ) were similarly distributed . After 1 hour of treatment , subjective responses to treatment ( P<.001 ) and median ( 5th-95th percentile ) PaO(2)/FIO(2 ) ratios were greater with CPAP ( 203 [ 45 - 431 ] mm Hg vs 151 [ 73 - 482 ] mm Hg ; P = .02 ) . No further difference in respiratory indices was observed between the groups . Treatment with CPAP failed to reduce the endotracheal intubation rate ( 21 [ 34 % ] vs 24 [ 39 % ] in the st and ard therapy group ; P = .53 ) , hospital mortality ( 19 [ 31 % ] vs 18 [ 30 % ] ; P = .89 ) , or median ( 5th-95th percentile ) intensive care unit length of stay ( 6.5 [ 1 - 57 ] days vs 6.0 [ 1 - 36 ] days ; P = .43 ) . A higher number of adverse events occurred with CPAP treatment ( 18 vs 6 ; P = .01 ) . CONCLUSION In this study , despite early physiologic improvement , CPAP neither reduced the need for intubation nor improved outcomes in patients with acute hypoxemic , nonhypercapnic respiratory insufficiency primarily due to acute lung injury . JAMA . 2000;284:2352 - 2360 Objective Noninvasive ventilation ( NIV ) fails more frequently for de novo acute respiratory failure ( de novo ) than for cardiogenic pulmonary edema ( CPE ) or acute-on-chronic respiratory failure ( AOC ) . The impact of NIV failure and success was compared between de novo and CPE or AOC after adjustment for disease severity . Setting s Patients requiring ventilatory support were enrolled in a prospect i ve survey in 70 French ICUs . Of 1076 patients requiring ventilatory support , 524 were eligible , including 299 de novo ( NIV use , 30 % ) and 225 CPE-AOC ( NIV use , 55 % ) . Design and analysis Independent risk factors associated with mortality and length of stay were identified by logistic regression analysis . The adjusted outcome of NIV success or failure was compared to that with endotracheal intubation without NIV . Results  NIV success was independently associated with survival in both de novo , adjusted OR 0.05 ( 95 % CI 0.01–0.42 ) , and CPE-AOC OR 0.03 ( CI 0.01–0.24 ) . NIV failure was associated with ICU mortality in the de novo group ( OR 3.24 , CI 1.61–6.53 ) but not in the CPE-AOC group . Nosocomial pneumonia was less common in patients successful with NIV .  NIV failure was associated with a longer ICU stay in CPE-AOC only . The overall use of NIV was independently associated with a better outcome only in CPE-AOC patients ( OR 0.33 , CI 0.15–0.73 ) . Conclusion The effect of NIV differs between de novo and CPE-AOC patients because NIV failure is associated with increased mortality for de novo patients . This finding should raise a note of caution when applying NIV in this indication Introduction : The role of non-invasive positive pressure ventilation delivered through a face mask in patients with flail chest is uncertain . We conducted a prospect i ve , r and omised 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 r and omly 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 PO2 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 The prognosis of patients suffering from respiratory failure ( RF ) after allogeneic hematopoietic SCT ( HSCT ) is poor . However , early treatment for using non-invasive ventilation ( NIV ) may be of benefit . We conducted a r and omized trial to prove the impact of early NIV  in patients in the early post-transplant period . A total of 526 patients undergoing HSCT in a single center were monitored for signs of RF . Patients with RF were enrolled into either treatment arm A ( oxygen supply only ) or treatment arm B ( oxygen+intermittent NIV ) . RF had to be diagnosed in 86 patients ( 16 % ) . RF was an independent risk factor for both short-term ( 100 day mortality/ OR 2.76 ; P<0.001 ) and long-term survival ( OR 1.57 ; P<0.01 ) . Although early RF treatment with NIV was associated with a decreased rate of failure to achieve sufficient oxygenation ( 39 % in arm A vs 24 % in arm B , P=0.17 ) , neither intensive care unit admission rate , nor need for intubation or survival parameters were affected by the treatment strategy . An early interventional strategy using NIV was not associated with improvement of the prognosis of the patients . The limited influence of NIV may be related to the study design allowing for switching of treatment in case of unsatisfactory efficacy CONTEXT Noninvasive ventilation ( NIV ) has been associated with lower rates of endotracheal intubation in population s of patients with acute respiratory failure . OBJECTIVE To compare NIV with st and ard treatment using supplemental oxygen administration to avoid endotracheal intubation in recipients of solid organ transplantation with acute hypoxemic respiratory failure . DESIGN AND SETTING Prospect i ve r and omized study conducted at a 14-bed , general intensive care unit of a university hospital . PATIENTS Of 238 patients who underwent solid organ transplantation from December 1995 to October 1997 , 51 were treated for acute respiratory failure . Of these , 40 were eligible and 20 were r and omized to each group . INTERVENTION Noninvasive ventilation vs st and ard treatment with supplemental oxygen administration . MAIN OUTCOME MEASURES The need for endotracheal intubation and mechanical ventilation at any time during the study , complications not present on admission , duration of ventilatory assistance , length of hospital stay , and intensive care unit mortality . RESULTS The 2 groups were similar at study entry . Within the first hour of treatment , 14 patients ( 70 % ) in the NIV group , and 5 patients ( 25 % ) in the st and ard treatment group improved their ratio of the PaO2 to the fraction of inspired oxygen ( FIO2 ) . Over time , a sustained improvement in PaO2 to FIO2 was noted in 12 patients ( 60 % ) in the NIV group , and in 5 patients ( 25 % ) r and omized to st and ard treatment ( P = .03 ) . The use of NIV was associated with a significant reduction in the rate of endotracheal intubation ( 20 % vs 70 % ; P = .002 ) , rate of fatal complications ( 20 % vs 50 % ; P = .05 ) , length of stay in the intensive care unit by survivors ( mean [ SD ] days , 5.5 [ 3 ] vs 9 [ 4 ] ; P = .03 ) , and intensive care unit mortality ( 20 % vs 50 % ; P = .05 ) . Hospital mortality did not differ . CONCLUSIONS These results indicate that transplantation programs should consider NIV in the treatment of selected recipients of transplantation with acute respiratory failure STUDY OBJECTIVE Noninvasive mechanical ventilation ( NIMV ) is beneficial for patients with acute respiratory failure ( ARF ) when added to medical treatment . However , its role as an alternative to conventional mechanical ventilation ( CMV ) remains controversial . Our aim was to compare the efficacy and re source consumption of NIMV against CMV in patients with ARF . DESIGN A r and omized , multicenter , controlled trial . SETTING Seven multi purpose ICUs . PATIENTS Sixty-four patients with ARF from various causes who fulfilled criteria for mechanical ventilation . INTERVENTION The noninvasive group received ventilation through a face mask in pressure-support mode plus positive end-expiratory pressure ; the conventional group received ventilation through a tracheal tube . MEASUREMENTS AND RESULTS Avoidance of intubation , mortality , and consumption of re sources were the outcome variables . Thirty-one patients were assigned to the noninvasive group , and 33 were assigned to the conventional group . In the noninvasive group , 58 % patients were intubated , vs 100 % in the conventional group ( relative risk reduction , 43 % ; p < 0.001 ) . Stratification by type of ARF gave similar results . In the ICU , death occurred in 23 % and 39 % ( p = 0.09 ) and complications occurred in 52 % and 70 % ( p = 0.07 ) in the noninvasive and conventional groups , respectively . There were no differences in length of stay . The Therapeutic Intervention Score System-28 , but not the direct nursing activity time , was lower in the noninvasive group during the first 3 days . CONCLUSIONS NIMV reduces the need for intubation and therapeutic intervention in patients with ARF from different causes . There is a nonsignificant trend of reduction in ICUs and hospital mortality together with fewer complications during ICU stay Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more BACKGROUND Noninvasive ventilation ( NIV ) is an emerging modality in the management of patients with acute respiratory failure . However , its role in severe acute asthma is not well defined . OBJECTIVE Evaluate the efficacy of NIV in severe acute asthma . METHODS Patients with severe acute asthma were r and omized to receive either st and ard medical therapy or NIV in addition to medical therapy . The primary outcomes were improvement in forced expiratory volume in the first second ( FEV1 ) , intensive care unit ( ICU ) stay , and hospital stay . The secondary outcomes were rate of improvement in respiratory rate , blood pH , ratio of PaO2 to fraction of inspired oxygen ( F(I)O2 ) , PaCO2 , requirement for inhaled medications , and failure of primary therapy . RESULTS Fifty-three patients with severe acute asthma ( 42 females and 11 males , mean + /- SD age 44 + /- 15 y , FEV1 < 30 % of predicted ) were r and omized to NIV ( n = 28 ) or st and ard medical therapy ( n = 25 ) . The baseline variables were similar in the 2 groups except for the mean duration of ast 
    Output:
    