***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: Background : In the assessment of severity in community acquired pneumonia ( CAP ) , the modified British Thoracic Society ( mBTS ) rule identifies patients with severe pneumonia but not patients who might be suitable for home management . A multicentre study was conducted to derive and vali date a practical severity assessment model for stratifying adults hospitalised with CAP into different management groups . Methods : Data from three prospect i ve studies of CAP conducted in the UK , New Zeal and , and the Netherl and s were combined . A derivation cohort comprising 80 % of the data was used to develop the model . Prognostic variables were identified using multiple logistic regression with 30 day mortality as the outcome measure . The final model was tested against the validation cohort . Results : 1068 patients were studied ( mean age 64 years , 51.5 % male , 30 day mortality 9 % ) . Age ⩾65 years ( OR 3.5 , 95 % CI 1.6 to 8.0 ) and albumin < 30 g/dl ( OR 4.7 , 95 % CI 2.5 to 8.7 ) were independently associated with mortality over and above the mBTS rule ( OR 5.2 , 95 % CI 2.7 to 10 ) . A six point score , one point for each of Confusion , Urea > 7 mmol/l , Respiratory rate ⩾30/min , low systolic(<90 mm Hg ) or diastolic ( ⩽60 mm Hg ) Blood pressure ) , age ⩾65 years ( CURB-65 score ) based on information available at initial hospital assessment , enabled patients to be stratified according to increasing risk of mortality : score 0 , 0.7 % ; score 1 , 3.2 % ; score 2 , 3 % ; score 3 , 17 % ; score 4 , 41.5 % and score 5 , 57 % . The validation cohort confirmed a similar pattern . Conclusions : A simple six point score based on confusion , urea , respiratory rate , blood pressure , and age can be used to stratify patients with CAP into different management groups 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 Abstract Objective : To explore three aspects of non-invasive pressure support ventilation ( NIPSV ) applied by face mask to patients with acute respiratory failure ( ARF ) due to severe community-acquired pneumonia ( CAP ) : ( 1 ) the initial acute effects on respiratory rate , gas exchange and hemodynamics , ( 2 ) the clinical course and outcome during ICU and hospital stay , ( 3 ) the nursing workload as measured by the daily PRN 87 ( Project Research in Nursing ) score . Setting : Medical ICU , University Hospital . Design : Prospect i ve , observational study . Patients : Patients without any prior history of chronic lung disease , consecutively admitted to the ICU to receive NIPSV for ARF due to severe CAP . Measurements and results ( means ± SD ) : Twenty-four patients aged 49±17 years , admission APACHE II 13±5 , were included . Admission PaO2/FIO2 , alveolar-arterial oxygen difference ( DA-aO2 ) and PaCO2 were 104±48 , 447±120 and 40±10 mmHg , respectively . All patients were normotensive . During the initial NIPSV  trial respiratory rate decreased from 34±8 to 28±10 breaths/min ( p<0.001 ) and arterial oxygenation improved ( PaO2/FIO2 104±48 vs 153±49 , DA-aO2 447±120 vs 370±180 mmHg , p<0.001 ) while PaCO2 remained unchanged . There were no hemodynamic effects . Subsequently , a total of 133 NIPSV trials were performed ( median duration 55 min , range 30–540 min ) over 1–7 days . No complication occurred during NIPSV . Sixteen patients were intubated ( 66 % ) 1.3±1 days after inclusion . Upon inclusion , the patients who were subsequently intubated were older ( 55±15 vs 37±12 years ) and more severely hypoxemic ( 63±11 vs 80±15 mmHg , p<0.05 ) than those not requiring intubation . Eight patients died ( 33 % ) , all in the intubated group . Median lengths of stay in the ICU and hospital were longer in intubated patients ( ICU 16 days , range 3–64 vs 6 days , range 3–7 , p<0.05 ; hospital 23 days , range 9–77 vs 9.5 days , range 4–42 , p<0.05 ) . Mean daily total PRN points were stable throughout the NIPSV period and were not different between the groups . Only 14 % of PRN points result ed from respiratory therapy interventions . PRN score was higher during the first 24 h following intubation than during the first 24 h of NIPSV ( 278±55 vs 228±24 points , p<0.05 ) . Conclusion : Despite initial improvement in arterial oxygenation with NIPSV in patients with ARF due to severe CAP , the intubation rate is high . However , the more favorable outcome and shorter ICU and hospital stays when intubation is avoided , as well as the short delay required to assess the success or failure of NIPSV warrants a trial of NIPSV in this setting . The nursing workload remains stable during NIPSV and does not result predominantly from respiratory therapy interventions OBJECTIVE We have reported previously on the use of noninvasive positive-pressure ventilation ( NPPV ) to assist spontaneous breathing in high-risk hypoxemic patients ( i.e. , PaO(2)/fraction of inspired oxygen [ FIO(2 ) ] ratio , < or = 100 ) who are undergoing diagnostic fiberoptic bronchoscopy ( FOB ) .  The efficacy of this intervention in patients with less severe forms of hypoxemia ( i.e. , PaO(2)/FIO(2 ) ratio , < 200 ) is unknown . PATIENTS AND METHODS Twenty-six patients with PaO(2)/FIO(2 ) ratios < or = 200 who required bronchoscopic BAL for suspected nosocomial pneumonia were entered into the study . Thirteen patients were r and omized during  FOB to receive NPPV , and 13 patients were r and omized to receive conventional oxygen supplementation by Venturi mask . The primary end points were changes in the PaO(2)/FIO(2 ) ratio during FOB and within 60 min of terminating the procedure . RESULTS AND OUTCOME : At study entry , the two groups were similar in terms of age , simplified acute physiologic score II values , and cardiorespiratory parameters . During FOB , the mean ( + /- SD ) PaO(2)/FIO(2 ) ratio increased by 82 % in the NPPV group ( 261 + /- 100 vs 139 + /- 38 ; p < 0.001 ) and decreased by 10 % in the conventional oxygen supplementation group ( 155 + /- 24 to 139 + /- 38 ; p = 0.23 ) . Sixty minutes after undergoing FOB , the NPPV group had a higher mean PaO(2)/FIO(2 ) ratio ( 176 + /- 62 vs 140 + /- 38 ; p = 0.09 ) , a lower mean heart rate ( 91 + /- 18 vs. 108 + /- 15 beats/min ; p = 0.02 ) , and no reduction in mean arterial pressure in comparison to a 15 % decrease from the baseline in the control group . One patient in the NPPV group and two patients in the control group required nonemergent intubation . Major bacterial isolates included Staphylococcus aureus ( 7 of 30 isolates ; 23 % ) and Pseudomonas aeruginosa ( 12 of 30 isolates ; 40 % ) . CONCLUSION In patients with severe hypoxemia , NPPV is superior to conventional oxygen supplementation in preventing gas-exchange deterioration during FOB with better hemodynamic tolerance Objective : In r and omized studies of heterogeneous patients with hypoxemic acute respiratory failure , noninvasive positive pressure ventilation ( NPPV ) was associated with a significant reduction in endotracheal intubation . The role of NPPV in patients with acute respiratory distress syndrome ( ARDS ) is still unclear . The objective was to investigate the application of NPPV as a first‐line intervention in patients with early ARDS , describing what happens in everyday clinical practice in centers having expertise with NPPV . Design : Prospect i ve , multiple‐center cohort study . Setting : Three European intensive care units having expertise with NPPV . Patients : Between March 2002 and April 2004 , 479 patients with ARDS were admitted to the intensive care units . Three hundred and thirty‐two ARDS patients were already intubated , so 147 were eligible for the study . Interventions : Application of NPPV . Measurements and Main Results : NPPV  improved gas exchange and avoided intubation in 79 patients ( 54 % ) . Avoidance of intubation was associated with less ventilator‐associated pneumonia ( 2 % vs. 20 % ; p < .001 ) and a lower intensive care unit mortality rate ( 6 % vs. 53 % ; p < .001 ) . Intubation was more likely in patients who were older ( p = .02 ) , had a higher Simplified Acute Physiology Score ( SAPS ) II ( p < .001 ) , or needed a higher level of positive end‐expiratory pressure ( p = .03 ) and pressure support ventilation ( p = .02 ) . Only SAPS II > 34 and a Pao2/Fio2 ≤175 after 1 hr of NPPV were independently associated with NPPV failure and need for endotracheal intubation . Conclusions : In expert centers , NPPV applied as first‐line intervention in ARDS avoided intubation in 54 % of treated patients . A SAPS II > 34 and the inability to improve Pao2/Fio2 after 1 hr of NPPV were predictors of failure A prospect i ve study of 132 patients with severe community-acquired pneumonia ( CAP ) treated in the ICU was carried out to determine the causative agents , the value of the clinical , 
    Output:
    
Non-invasive ventilation can reduce the risk of death in the ICU , endotracheal intubation , shorten ICU stay and length of intubation .
However , the review indicates that non-invasive ventilation may be more beneficial than st and ard oxygen supplementation via a Venturi mask for pneumonia