title: Can (and should) the venous tone be monitored at the bedside?
abstract: OBJECTIVE
  Most of our blood volume is contained in the venous compartment. The so-called 'compliant veins' are an adjustable blood reservoir, which is playing a paramount role in maintaining haemodynamic stability. The purpose of this study is to review what is known about this blood reservoir and how we can use this information to assess the cardiovascular state of critically ill patients.
  
  
  RESULTS
  The mean systemic filling pressure (Pmsf) is the pivot pressure of the circulation, and a quantitative index of intravascular volume. The Pmsf can be measured at the bedside by three methods described in critically ill patients. The Pmsf can be modified by the fluid therapy and vasoactive medications.
  
  
  CONCLUSIONS
  The Pmsf along with other haemodynamic variables can provide valuable information to correctly understand the cardiovascular status of critically ill patients and better manage the fluid therapy and cardiovascular support. Future studies using the Pmsf will show its usefulness for fluid administration.
authors.affiliation: aGeneral Intensive Care Unit, St. Georges Healthcare NHS Trust bCardiovascular Sciences Institute, St George's University of London, London, UK.
authors.forename: Hollmann D
authors.initials: HD
authors.lastname: Aya
authors.forename: Maurizio
authors.initials: M
authors.lastname: Cecconi
mesh_terms: D002302:Cardiac Output / Q000502:physiology; D002496:Central Venous Pressure / Q000502:physiology*; D016638:Critical Illness; D005440:Fluid Therapy / Q000379:methods; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008991:Monitoring, Physiologic; D000067716:Point-of-Care Testing