title: Transvesical Intra-Abdominal Pressure Measurement in Newborn: What Is the Optimal Saline Volume Instillation?
abstract: OBJECTIVE
  To determine the optimal saline volume bladder instillation to measure intravesical pressure in critically ill newborns weighing less than 4.5 kg, and to establish a reference of intra-abdominal pressure value in this population.
  
  
  METHODS
  Prospective monocentric study.
  
  
  METHODS
  Neonatal ICU and PICU.
  
  
  METHODS
  Newborns, premature or not, weighing less than 4.5 kg who required a urethral catheter.
  
  
  RESULTS
  Patients were classified into two groups according to whether they presented a risk factor for intra-abdominal hypertension. Nine intravesical pressure measures per patient were performed after different volume saline instillation. The first one was done without saline instillation and then by increments of 0.5 mL/kg to a maximum of 4 mL/kg. Linear models for repeated measurements of intravesical pressure with unstructured covariance were used to analyze the variation of intravesical pressure measures according to the conditions of measurement (volume instilled). Pairwise comparisons of intravesical pressure adjusted mean values between instillation volumes were done using Tukey tests, corrected for multiple testing to determine an optimal instillation volume. Forty-seven patients with completed measures (nine instillations volumes) were included in the analysis. Mean intravesical pressure values were not significantly different when measured after instillation of 0.5, 1, or 1.5 mL/kg, whereas measures after instillation of 2 mL/kg or more were significantly higher. The median intravesical pressure value in the group without intra-abdominal hypertension risk factor after instillation of 1 mL/kg was 5 mm Hg (2-6 mm Hg).
  
  
  CONCLUSIONS
  The optimal saline volume bladder instillation to measure intra-abdominal pressure in newborns weighing less than 4.5 kg was 1 mL/kg. Reference intra-abdominal pressure in this population was found to be 5 mm Hg (2-6 mm Hg).
authors.affiliation: 1Paediatric Intensive Care Unit, CHU Rennes, Rennes, France. 2INSERM, U1099, Rennes, France. 3Univ Rennes 1, Laboratoire de Traitement du Signal et de l'Image (LTSI), Rennes, France. 4Neonatal Intensive Care Unit, CHU Rennes, Rennes, France. 5Paediatric Surgery Department, CHU Rennes, Rennes, France. 6Univ Rennes 1, Faculty of Medicine, Rennes, France. 7CIC-P INSERM, U0203, Rennes, France. 8Anaesthesiology and Reanimation Department, CHU Rennes, Rennes, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Defontaine
authors.forename: Olivier
authors.initials: O
authors.lastname: Tirel
authors.forename: Nathalie
authors.initials: N
authors.lastname: Costet
authors.forename: Alain
authors.initials: A
authors.lastname: Beuchée
authors.forename: Bruno
authors.initials: B
authors.lastname: Ozanne
authors.forename: Théophile
authors.initials: T
authors.lastname: Gaillot
authors.forename: Alexis Pierre
authors.initials: AP
authors.lastname: Arnaud
authors.forename: Eric
authors.initials: E
authors.lastname: Wodey
mesh_terms: D000005:Abdomen / Q000502:physiology*; D000283:Administration, Intravesical; D016638:Critical Illness; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D008297:Male; D011312:Pressure; D011446:Prospective Studies; D012016:Reference Values; D012965:Sodium Chloride / Q000008:administration & dosage*; D001743:Urinary Bladder / Q000503:physiopathology*
chemical_list: D012965:Sodium Chloride