Respiratory Literature Summaries

OVERVIEW

• ARDS
• VAP
• VTE
• Miscellaneous

ARDS

• see Acute Respiratory distress Syndrome (ARDS) Literature Summaries

VENTILATOR ACQUIRED PNEUMONIA

Drakulovic, M.B., et al (1999) “Supine body position as a risk factor for nosocomial pneumonia in mechanically ventilated patients: a randomised trial” Lancet 3541851-1858

• n = 86
• single centre
• supine VS semirecumbent -> study stopped at interim analysis c/o significant reduction in pneumonia in the semirecumbent -> risk factors for pneumonia = supine position + enteral nutrition

Fagon, J.Y., et al (2000) “Invasive and non-invasive strategies for management of suspected ventilator-associated pneumonia. A randomized trial” Ann Intern Med 132:621-630

• MCT
• n = 413
• inclusion criteria: ventilator-associated pneumonia
• intervention = invasive management (direct bronchoscopy + lavage -> cultures and cessation of antibiotics if negative) VS non-invasive management (standard tracheal aspirates and empirical treatment) -> reduced mortality in invasive group (14 and 28 days) -> reduced antibiotic group in invasive group

VENOUS THROMBOEMBOLISM

Geerts, W.H., et al (2004) “Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy” Chest 126:338-400

• detailed guidelines on the prevention of VTE
• there is an absence of data in the critically ill

Konstantinides, S., et al – Management Strategies and Prognosis of Pulmonary Embolism – 3 Trial Investigators. (2002) “Heparin plus alteplase compared with heparin alone in patients with submassive pulmonary embolism” N Engl J Med 347:1143-1150

• double blind RCT
• n = 256
• acute PE and PHT or RV dysfunction (not with hypotension)
• heparin VS heparin + alteplase -> reduces clinical deterioration -> reduced need for interventions (CPR, emergency embolectomy, catheter thrombosis fragmentation) -> no fatal bleeding in lysis group -> did not change inhospital survival -> consider thrombolysis in sub-massive PE

The PROTECT Investigators for the Canadian Critical Care Trials Group and the Australian and New Zealand Intensive Care Society Clinical Trials Group (2011) – Dalteparin vs Unfractionated Heparin in Critically Ill Paitients – NEJM, March

• MRCT
• n = 3764 adults
• primary end-point: proximal DVT assessment by twice weekly U/S

-> overall incidence proximal DVT incidence of 5.6% -> no difference in rates of proximal DVT between groups -> most DVT’s occur in ICU (not the ward) -> decreased PE rate in dalteparin group (NNT 100) -> no difference in bleeding -> no difference in HITS (trend to decrease with dalteparin)

MISCELLANEOUS

Naveanu, M. et al (2010) “Effect of oral beta-blocker on short and long term mortality in patients with acute respiratory failure: results from the Basel II-ICU study” Critical Care, 14:1-10

• sub-study of an MRCT looking at BNP in the guidance of acute respiratory failure (BNP for Acute Shortness of Breath Evaluation II-ICU trial)
• 7 ICU’s
• Switzerland
• n = 314
• inclusion criteria: admission to ICU with respiratory failure
• exclusion criteria: trauma, severe renal disease, previous BNP, > 12 hours of eligibility, sepsis, CPR, shock.
• randomized to BNP measurement vs no BNP measurement

-> in hospital mortality 16% -> one year mortality 41% -> renal dysfunction, IHD, malignancy associated with increased mortality -> oral beta-blockers on admission or started during admission was associated with a lower risk of death (in hospital and at 1 year irrespective of whether respiratory failure cardiac or not) -> discontinuation of beta-blockers associated with higher mortality

Weaknesses

• mechanism uncertain
• post-hoc analysis
• not generalisable to sepsis or shock -> shown to decrease mortality in COPD, heart failure, IHD, HT and now respiratory failure in ICU