title: Does positive end-expiratory pressure ventilation improve left ventricular function? A comparative study by transesophageal echocardiography in cardiac and noncardiac patients.
abstract: OBJECTIVE
  Positive end-expiratory pressure (PEEP) has been proposed to improve cardiac output in patients with left ventricular (LV) dysfunction. This study was designed to compare quantitative global and regional LV performance in response to PEEP in patients with normal and poor LV function.
  
  
  METHODS
  A prospective clinical trial.
  
  
  METHODS
  Adult medical ICU in a university hospital.
  
  
  METHODS
  Twelve critically ill patients requiring respiratory support and divided into two groups according to baseline transesophageal echocardiographic (TEE) measurements: normal LV dimensions and fractional area of contraction (FAC=61+/-5%) (n=7) and dilated cardiomyopathy with reduced FAC (21+/-1%) (n=5).
  
  
  RESULTS
  All patients were studied when two successive levels of PEEP (best PEEP as the highest value of respiratory compliance and high PEEP as best PEEP+10 cm H2O) were applied. Global systolic LV performance and quantitative regional wall motion analysis performed by the centerline method were assessed on the TEE transgastric short-axis view. End-systolic wall stress (ESWS) was used as a reliable indication of LV afterload. PEEP reduced LV dimensions asymmetrically in both groups of patients and septolateral diameter significantly decreased without affecting global LV systolic performance. Additionally, high PEEP produced a significant impairment in septal kinetics as evidenced by the centerline method. High PEEP also decreased ESWS for all patients (-27% in normal group and -23% in cardiac group, p<0.05) without significant improvement in global systolic LV performance (FAC: +2% in normal group and +0% in cardiac group; not significant).
  
  
  CONCLUSIONS
  PEEP cannot be recommended routinely to improve LV performance in patients with severe dilated cardiomyopathy.
authors.affiliation: Respiratory Intensive Care Unit, Hôpital Ambroise Paré, University of Paris V, France.
authors.forename: J L
authors.initials: JL
authors.lastname: Fellahi
authors.forename: B
authors.initials: B
authors.lastname: Valtier
authors.forename: A
authors.initials: A
authors.lastname: Beauchet
authors.forename: J P
authors.initials: JP
authors.lastname: Bourdarias
authors.forename: F
authors.initials: F
authors.lastname: Jardin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002302:Cardiac Output; D002311:Cardiomyopathy, Dilated / Q000150:complications*; D017548:Echocardiography, Transesophageal; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011175:Positive-Pressure Respiration; D011446:Prospective Studies; D012129:Respiratory Function Tests; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D016277:Ventricular Function, Left / Q000502:physiology*