***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: Introduction Absence of pulmonary perfusion during cardiopulmonary bypass ( CPB ) may be associated with reduced postoperative oxygenation . Effects of active pulmonary artery perfusion were explored in patients with chronic obstructive pulmonary disease ( COPD ) undergoing cardiac surgery . Methods 90 patients were r and omised to receive pulmonary artery perfusion during CPB with either oxygenated blood ( n=30 ) or histidine-tryptophan-ketoglutarate ( HTK ) solution ( n=29 ) compared with no pulmonary perfusion ( n=31 ) . The co primary outcomes were the inverse oxygenation index compared at 21 hours after starting CPB and longitudinally in a mixed-effects model ( MEM ) . Secondary outcomes were tracheal intubation time , serious adverse events , mortality , days alive outside the intensive care unit ( ICU ) and outside the hospital . Results 21 hours after starting CPB patients receiving pulmonary artery perfusion with normothermic oxygenated blood had a higher oxygenation index compared with no pulmonary perfusion ( mean difference ( MD ) 0.94 ; 95 % CI 0.05 to 1.83 ; p=0.04 ) . The blood group had also a higher oxygenation index both longitudinally ( MEM , p=0.009 ) and at 21 hours ( MD 0.99 ; CI 0.29 to 1.69 ; p=0.007 ) compared with the HTK group . The latest result corresponds to a difference in the arterial partial pressure of oxygen of 23 mm Hg with a median fraction of inspired oxygen of 0.32 . Yet the blood or HTK groups did not demonstrate a longitudinally higher oxygenation index compared with no pulmonary perfusion ( MEM , p=0.57 and 0.17 ) . Similarly , at 21 hours there was no difference in the oxygenation index between the HTK group and those no pulmonary perfusion ( MD 0.06 ; 95 % CI −0.73 to 0.86 ; p=0.87 ) . There were no statistical significant differences between the groups for the secondary outcomes . Discussion Pulmonary artery perfusion with normothermic oxygenated blood during cardiopulmonary bypass appears to improve postoperative oxygenation in patients with COPD undergoing cardiac surgery .  Pulmonary artery perfusion with hypothermic HTK solution does not seem to improve postoperative oxygenation . Trial registration number NCT01614951 ; Pre- results OBJECTIVES To analyze sources search ed in Cochrane review s , to determine the proportion of trials included in review s that are indexed in major data bases , and to compare the quality of these trials with those from other sources . METHODS All new systematic review s in the Cochrane Library , Issue1 2001 , that were restricted to r and omized controlled trials ( RCTs ) or quasi- RCTs were selected . The sources search ed in the review s were recorded , and the trials included were checked to see whether they were indexed in four major data bases . Trials not indexed were checked to determine how they could be identified . The quality of trials found in major data bases was compared with those found from other sources . RESULTS The range in the number of data bases search ed per review ranged between one and twenty-seven . The proportion of the trials in the four data bases were Cochrane Controlled Trials Register = 78.5 % , MEDLINE = 68.8 % , Embase = 65.0 % , and Science/Social Sciences Citation Index = 60.7 % . Search ing another twenty-six data bases after Cochrane Controlled Trials Register ( CCTR ) , MEDLINE , and Embase only found 2.4 % additional trials . There was no significant difference between trials found in the CCTR , MEDLINE , and Embase compared with other trials , with respect to adequate allocation concealment or sample size . CONCLUSIONS There was a large variation between review s in the exhaustiveness of the literature search es . CCTR was the single best source of RCTs . Additional data base search ing retrieved only a small percentage of extra trials . Contacting authors and manufacturers to find unpublished trials appeared to be a more effective method of obtaining the additional better quality trials OBJECTIVE Improved respiratory outcome has been shown after selective pulsatile pulmonary perfusion ( sPPP ) during cardiopulmonary bypass ( CPB ) .  No contemporary study has analysed the impact of sPPP on alveolar and systemic inflammatory response in humans . METHODS Sixty-four patients undergoing a coronary artery bypass graft ( CABG ) were r and omized to sPPP or st and ard CPB ( 32 patients each ) . An alveolar-arterial oxygen gradient ( A-aDO(2 ) ) was measured preoperatively ( T0 ) , at ICU arrival ( T1 ) , 3 h postoperatively ( T2 ) and postextubation ( T3 ) . The bronchoalveolar lavage ( BAL ) was collected at T0 , T1 and T2 . White blood cells ( WBCs ) , neutrophils , mononucleates and lymphocytes in BAL infiltrates were compared between the two groups . A cytokine assay for interleukin-1 ( IL-1 ) , IL-8 , tumour necrosis factor alpha ( TNF-α ) , monocyte chemotactic protein-1 ( MCP-1 ) , growth regulated oncogene-alpha ( GRO-α ) and interferon (IFN)-γ was collected from the BAL and peripheral blood at the same time-points . Repeated-measure analysis of variance and non-parametric statistics were used to assess the between-group and during time differences . RESULTS The two groups proved comparable for perioperative variables . A-aDO(2 ) proved better after sPPP ( group-P = 0.0001 ; group time-P < 0.0001 ) . BAL infiltrates after sPPP showed lower WBCs , neutrophils and lymphocytes ( group-P = 0.0001 , group time-P = 0.0001 for all ) together with higher mononucleates ( group-P = 0.0001 , group time-P = 0.0001 ) . Proinflammatory cytokines and chemokine MCP-1 were lower in BAL after sPPP ( group-P = 0.005 , 0.034 , 0.036 and 0.005 , and group time-P = 0.001 , 0.009 , 0.001 and 0.0001 for IL-1 , IL-8 , TNF-α and MCP-1 , respectively ) , whereas the immune modulator IFN-γ significantly augmented after sPPP ( time-P = 0.0001 ) but remained stable after the st and ard CPB ( time-P = 0.101 , group-P = 001 , group time-P = 0.0001 ) . Indeed , serum cytokines were not different in the two groups during the study ( P = NS at single time-points and as a function of time ) . CONCLUSIONS sPPP attenuates alveolar inflammation , as demonstrated by the lower neutrophilic/lymphocytic alveolar infiltration , and the secretion of anti-inflammatory rather than proinflammatory mediators OBJECTIVE Acute lung injury still accounts for postoperative mortality after cardiopulmonary bypass ( CPB ) .  The safety and the efficacy of pulsatile pulmonary perfusion ( PPP ) during CPB were analyzed . Preliminary results of the first PPP trial in human beings are reported . METHODS Thirty low-risk coronary artery bypass grafting ( CABG ) patients were prospect ively r and omized to receive PPP with oxygenated blood during CPB and aortic cross-clamping ( 15 patients , PPP-group ) or to conventional CPB ( 15 patients , control group ) . Alveolo-arterial oxygen gradient ( A-aDO(2 ) ) was set as the primary end point and collected preoperatively , at intensive care unit ( ICU ) arrival ( T1 ) , 3h postoperatively ( T2 ) , and post extubation ( T3 ) . Secondary end points were collected at the same time points and consisted of respiratory indices ( partial pressure of arterial oxygen/fraction of inspired O(2 ) ( PaO(2)/FiO(2 ) ) , lung compliance , mixed-venous partial pressure of oxygen ( pO(2 ) ) ) and hemodynamic pulmonary parameters ( indexed pulmonary vascular resistances ( PVRI ) , pulmonary arterial pressure ( PAP ) , pulmonary capillary wedge pressure ( PCWP ) , and cardiac index ( CI ) ) . Bronchoalveolar lavage ( BAL ) fluid was collected preoperatively , at ICU arrival ( T1-BAL ) and after 4h . RESULTS There were no PPP-related complications . Patients undergoing PPP showed a better preserved A-aDO(2 ) ( group-p=0.001 ) throughout the study period ( group × time-p = 0.0001 ) . PaO(2)/FiO(2 ) and lung compliance were better preserved by PPP ( group-p and group × time-p ≤ 0.05 for all ) . Pulmonary hemodynamic status was positively influenced by PPP , as shown by the higher CI ( group-p=0.0001 , group × time-p = 0.0001 ) , and the lower PVRI , PAP , and PCWP ( group-p ≤0.001 , group × time-p=0.0001 for all ) . Postoperative BAL specimens demonstrated a lower absolute count of white blood cells ( group-p=0.0001 ) , a higher percentage of monocytes/macrophages ( group-p=0.027 ) , and a lower percentage of neutrophils ( group-p=0.015 ) after PPP . CONCLUSIONS Oxygenated blood PPP proved safe and significantly ameliorated pulmonary hemodynamic parameters and respiratory indices in low-risk CABG OBJECTIVE We have recently shown that a considerable amount of pro-inflammatory cytokines is released during pulmonary passage after aortic declamping in patients undergoing coronary artery bypass grafting .  The present study was performed to investigate whether bilateral extracorporeal circulation with the lungs as oxygenators can reduce the inflammatory responses of the lungs . METHODS Eighteen consecutive patients undergoing coronary artery bypass grafting  were r and omly assigned to routine extracorporeal circulation with cannulation of right atrium and aorta ( routine circulation , ten patients ) or to a bilateral extracorporeal circulation with additional cannulation of left atrium and pulmonary artery ( bilateral circulation , eight patients ) . Blood was simultaneously drawn from right atrium and pulmonary vein at 1 , 10 and 20 min reperfusion . The levels of interleukin (IL)-6 and IL-8 and the adhesion molecules CD41 and CD62 on platelets and CD11b and CD41 on leukocytes were determined . Because of considerable interindividual scatter , the pulmonary venous levels are normalized to percent of the respective right atrial value at each time point . RESULTS At 1 min reperfusion pulmonary venous levels of IL-6 and IL-8 in routine circulation were + 44+/-15 % and + 43+/-28 % of the respective right atrial values . The respective values in bilateral circulation were -3+/-4 % and -6+/-7 % ( P=0.02 and P=0.05 vs. respective right atrium ) . Similar increments were found after 10 and 20 min . Platelet-monocyte coaggregates were retained during pulmonary passage at 1 min reperfusion in routine circulation ( -21+/-6 % ) , but washed out in bilateral circulation ( + 5+/-8 % , P=0 . 007 ) . At 20 min reperfusion , activated polymorphonuclear neutrophils ( PMN ) were retained in routine circulation ( -16+/-9 % ) but washed out in bilateral circulation ( + 19+/-29 % , P=0.05 ; all data given as mean+/-SEM ) . CONCLUSIONS Bilateral extracorporeal circulation without an artificial oxygenator significantly reduces the inflammatory responses during pulmonary passage after aortic declamping This review summarizes the (patho)-physiological effects of  ventilation with high FiO2 ( 0.8–1.0 )  , with a special focus on the most recent clinical evidence on its use for the management of circulatory shock and during medical emergencies .  Hyperoxia is a cornerstone of the acute management of circulatory shock , a concept which is based on compelling experimental evidence that compensating the imbalance between O2 supply and requirements ( i.e. , the oxygen dept ) is crucial for survival , at least after trauma . On the other h and , “ oxygen toxicity ” due to the increased formation of reactive oxygen species limits its use , because it may cause serious deleterious side effects , especially in conditions of ischemia/reperfusion . While these effects are particularly pronounced during long-term administration , i.e. , beyond 12–24 h , several retrospective studies suggest that even hyperoxemia of shorter duration is also associated with increased mortality and morbidity . In fact , albeit the clinical evidence from prospect i ve studies is surprisingly scarce , a recent meta- analysis suggests that hyperoxia is associated with increased mortality at least in patients after cardiac arrest , stroke , and traumatic brain injury . Most of these data , however , originate from heterogenous , observational studies with inconsistent results , and therefore , there is a need for the results from the large scale , r and omized , controlled clinical trials on the use of hyperoxia , which can be anticipated within the next 2–3 years . Consequently , until then , “ conserv 
    Output:
    
Last , review authors found no comparable data for the secondary outcome inflammatory markers .
The effects of pulmonary artery perfusion with blood during cardiopulmonary bypass ( CPB ) are uncertain owing to the small numbers of participants included in meta-analyses .
Risks of death and serious adverse events may be higher with pulmonary artery perfusion with blood during CPB , and robust evidence for any beneficial effects is lacking .