title: Primary and secondary intra-abdominal hypertension--different impact on ICU outcome.
abstract: OBJECTIVE
  To investigate the differences in incidence, time course and outcome of primary versus secondary intra-abdominal hypertension (IAH), and to evaluate IAH as an independent risk factor of mortality in a presumable risk population of critically ill patients.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  General intensive care unit of a university hospital.
  
  
  METHODS
  A total of 257 mechanically ventilated patients at presumable risk for the development of IAH were studied during their ICU stay and followed up for 90-day survival.
  
  
  METHODS
  Repeated measurements of intra-abdominal pressure (IAP).
  
  
  RESULTS
  IAP was measured intermittently, via bladder. IAH (sustained or repeated IAP > or = 12 mmHg) developed in 95 patients (37.0%). Primary IAH was observed in 60 and secondary IAH in 35 patients. Patients with secondary IAH demonstrated a significant increase of mean IAP during the first three days (mean DeltaIAP was 2.2 +/- 4.7 mmHg), whilst IAP decreased (mean DeltaIAP -1.1 +/- 3.7 mmHg) in the patients with primary IAH. The patients with IAH had a significantly higher ICU- (37.9 vs. 19.1%; P = 0.001), 28-day (48.4 vs. 27.8%, P = 0.001), and 90-day mortality (53.7 vs. 35.8%, P = 0.004) compared to the patients without the syndrome. Patients with secondary IAH had a significantly higher ICU mortality than patients with primary IAH (P = 0.032). Development of IAH was identified as an independent risk factor for death (OR 2.52; 95% CI 1.23-5.14).
  
  
  CONCLUSIONS
  Secondary IAH is less frequent, has a different time course and worse outcome than primary IAH. Development of IAH during ICU period is an independent risk factor for death.
authors.affiliation: Clinic of Anaesthesiology and Intensive Care, University of Tartu, Puusepa 8, 51014, Tartu, Estonia. annika.reintam@itk.ee
authors.forename: Annika
authors.initials: A
authors.lastname: Reintam
authors.forename: Pille
authors.initials: P
authors.lastname: Parm
authors.forename: Reet
authors.initials: R
authors.lastname: Kitus
authors.forename: Hartmut
authors.initials: H
authors.lastname: Kern
authors.forename: Joel
authors.initials: J
authors.lastname: Starkopf
mesh_terms: D000005:Abdomen; D003161:Compartment Syndromes / Q000145:classification / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D006973:Hypertension / Q000145:classification / Q000209:etiology* / Q000503:physiopathology*; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D011312:Pressure; D011446:Prospective Studies; D012372:ROC Curve; D012121:Respiration, Artificial / Q000009:adverse effects; D012307:Risk Factors; D012720:Severity of Illness Index