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Paper text:
ventilator - associated pneumonia ( vap ) is strongly associated with adverse outcomes in mechanically ventilated patients in the intensive care unit ( icu ) .
its incidence is about 8% to 20%   and mortality ranges between 20% and 50% .
consequently , vap has considerable impact on morbidity , length of stay and cost of icu care .
kollef and coworkers   conducted a retrospective cohort study involving 76 patients in an urban tertiary hospital who were recruited over 5 years .
the objective was to identify predictors of 30-day mortality and hospital costs in patients with vap attributed to potentially antibiotic - resistant gram - negative bacteria ( pseudomonas aeruginosa , acinetobacter spp . and
patients receiving their first dose of appropriate antibiotic therapy within 24 hours of bronchoalveolar lavage ( bal ) sampling had a statistically lower 30-day mortality rate and hospitalization cost as compared with patients receiving their first dose of appropriate therapy more than 24 hours after bal ( 17.2% versus 50.0% ) .
the authors conclude that prompt ( < 24 hours ) microbiological diagnosis and appropriate initial antimicrobial therapy produced healthier outcome data ; and that appropriate changes should be made to local empirical antibiotic policies in vap in the case of higher rates of vap due to antibiotic - resistant bacteria . in a second report
, el solh and colleagues   suggested that short - course (  7 days ) antimicrobial therapy may not be adequate .
the investigators studied the high mortality figures in pseudomonas vap and evaluated causes of microbial persistence in the alveolar space despite adequate antimicrobial therapy .
they hypothesized that failure to eradicate p. aeruginosa from the lung is linked to type iii secretory system isolates ( cytotoxins indicating virulence ) .
thirty - four patients with p. aeruginosa vap underwent noninvasive bal at the onset of vap and on day 8 after initiation of antibiotic therapy .
analysis for type iii cytotoxins was undertaken and results indicated that about 50% of the patients had persistence of type iii secretory system cytotoxins .
the persistence of the cytotoxins was attributed to the delay to eradication of the micro - organisms , and hence the recommendation is for longer courses of antimicrobial therapy .
kollef and coworkers produced another report from the nascent trial , which is a multicentre randomized single blinded study including about 2,003 patients considered for the trial .
the primary outcome was the incidence vap by means of bal fluid analysis at 24 hours .
patients were assigned to undergo intubation with one of two high - volume , low - pressure endotracheal tubes ( etts ) , which were similar except for a silver coating on the experimental tube .
the microbiologically confirmed rate of vap in the treatment limb was 4.8% and that in the conventional limb was 7.5% , with a relative risk reduction of 35.9% .
the investigators suggested that patients receiving a silver - coated ett had a statistically significant reduction in the incidence of vap and delayed time to vap occurrence as compared with those receiving a similar , uncoated tube , although there was not much impact on length of stay and overall mortality .
does this provide a rationale for using silver - lined etts in patients who are likely to require ventilation for longer than 24 hours ?
finally , we examine another paper published in critical care medicine   dealing with outcome data from vap patients with high bacterial loads .
the authors investigated the frequency and outcomes of ventilated patients with newly acquired , large - burden infection with p. aeruginosa .
a total of 69 patients were enrolled into the prospective study over a 4-year period who required more than 48 hours of mechanical ventilation and were identified as having newly acquired p. aeruginosa in their lower respiratory tracts .
daily surveillance cultures of endotracheal aspirates , pseudomonas quantification and clinical signs of infection were analyzed .
forty - five out of 69 patients had high pseudomonas burdens , but about one - third of these did not meet clinical criteria for vap diagnosis but still had statistically significant higher risk for death ( adjusted hazard ratio = 37.53 ) as compared with the patients who had clinically diagnosed p. aeruginosa vap .
furthermore , more patients with high p. aeruginosa burdens secreted the type iii secretion facilitator protein pcrv , suggesting higher virulence .
is it time to revisit the clinical criteria for vap diagnosis , with greater emphasis on quantification of respiratory tract bacterial load ?
neumann and coworkers reported data from the brainit database concerning use of hyperventilation strategies and adherence to brain trauma foundation guidelines after traumatic brain injury ( tbi ) in intensive care medicine .
this was a retrospective study of monitoring data from 22 european centres and involved 151 patients .
the latest editions of the brain trauma foundation guidelines maintain a restricted use of hyperventilation for the treatment of tbi because of its negative impact on cerebral blood flow / oxygenation and clinical outcome .
the study utilized data from nearly 8,000 blood gas analyses , representing ventilation episodes along with related minute by minute intracranial pressure data .
results from the study indicate that there was general adherence to guidelines except in cases of early prophylactic hyperventilation and cerebral oxygenation monitoring in forced hyperventilation .
the authors suggest that , in the absence of elevated intracranial pressure , hyperventilation is better avoided ; and that intentional reduction in arterial carbon dioxide tension to below 35 mmhg has little supporting evidence .
use of activated protein c ( apc ) in severe sepsis following the prowess and address studies received a major boost throughout the world in all major icus .
it has been widely accepted that plasma protein c levels are low in patients with acute lung injury ( ali ) ( even without sepsis ) , with higher mortality / morbidity figures .
a report recently published in the american journal of respiratory and critical care medicine   examined the efficacy of apc as a therapy for patients with ali .
american / european consensus criteria for ali were used to identify suitable patients , and those with severe sepsis and an acute physiology and chronic health evaluation ii score of 25 or greater were excluded .
eligible patients were randomly assigned to either receive apc or placebo ( double blinded ) within 72 hours .
the results revealed that the apc - treated group had increased plasma protein c levels and decreased pulmonary dead space fraction , but sadly this did not translate into clinical benefit , there being no difference in the number of ventilator - free days between the two groups .
hence , the investigators concluded that apc did not improve outcomes from ali in the absence of severe sepsis and high disease severity .
results from beautiful , a randomized , double - blind , placebo - controlled trial evaluating the use of ivabradine for patients with stable coronary artery disease and left ventricular systolic dysfunction , were recently published in the lancet .
fox and coworkers   exploited this effect of the drug in more than 10,000 patients with stable coronary artery disease and left ventricular ejection fraction less than 40% recruited over 2 years .
the primary end - point was a composite of cardiovascular death , admission to hospital for acute myocardial infarction and admission to hospital for new onset or worsening heart failure .
the results indicated that the drug did not improve primary endpoints but improved secondary end - points .
the investigators suggested that use of the drug in patients with higher heart rates ( more than 70 beats / minute ) reduced the incidence of coronary artery disease outcomes . ' on - time 2 ' data were also recently published in the lancet .
this was a multicentre , double - blind trial including 984 patients , who were randomly assigned to receive tirofiban ( gpiib / iiia inhibitor ) and placebo .
the primary end - point was the extent of residual st - segment deviation 1 hour after percutaneous coronary intervention .
the study identified significant benefit from prehospital use of tirofiban in patients with acute st - segment elevation myocardial infarction undergoing primary coronary angioplasty ( percutaneous coronary intervention ) .
reintam and coworkers   reported findings from a study in which they evaluated the differential impact of primary and secondary intra - abdominal hypertension ( iah ) on outcomes in intensive care medicine . this was a prospective study of 257 mechanically ventilated patients deemed to be at considerable risk for development of iah .
these patients underwent repeated measurements of intra - abdominal pressure ( iap ) during their icu stay and were followed up to 90-day survival .
the authors incorporated the new consensus definitions recently established by the world society of the abdominal compartment syndrome .
 iah is sustained or repeated pathological elevation of iap to 12 mmhg or greater .
 abdominal compartment syndrome is sustained iap above 20 mmhg along with a new organ dysfunction . 
primary iah is a condition associated with injury or disease in the abdomino - pelvic region that frequently requires early surgical or interventional radiological intervention ( for example , peritonitis , pancreatitis , bowel disease , or abdominal trauma ) .  ' secondary iah ' refers to conditions that do not originate from the abdomino - pelvic region ( for example , sepsis / shock , polytrauma , cardiopulmonary disease , intoxications , or burns ) .
iah developed in 95 patients ( 37.0% ) with primary iah ( n = 60 ) and secondary iah ( n = 35 ) .
patients with secondary iah exhibited a significant increase in mean iap during the first 3 days , whereas iap decreased in the patients with primary iah .
the patients with iah had a significantly higher mortality compared with patients without the syndrome .
the authors concluded the following : secondary iah is less frequent , has a different time course and worse outcome ; iah was an independent predictor of icu adverse outcome ; and icu patients with two or more risk factors should undergo daily iap measurement .
this study was accompanied by an excellent editorial review   that highlighted the importance of understanding the mechanism of injury in iah / abdominal compartment syndrome .
the review also proposed the concept of acute bowel injury and acute intestinal distress syndrome .
ali : acute lung injury ; apc : activated protein c ; bal : bronchoalveolar lavage ; ett : endotracheal tube ; iah : intra - abdominal hypertension ; iap : intra - abdominal pressure ; icu : intensive care unit ; tbi : traumatic brain injury ; vap : ventilator - associated pneumonia .
ventilator - associated pneumonia is a familiar foe in intensive care units , but those associated with pseudomonas aeruginosa have a particularly adverse impact on outcome . 
 correct antibiotic therapy and a novel endotracheal tube may reduce this burden . 
 does activated protein c improve outcome from acute lung injury and what is the role played by hyperventilation therapy in traumatic brain injury ? 
 recent research has attempted to answer these questions . 
 further novel approaches have been evaluated in the management of ischaemic heart disease , and more light has been shed on acute bowel injury .