title: Changes in the mean systemic filling pressure during a fluid challenge in postsurgical intensive care patients.
abstract: OBJECTIVE
  The difference between mean systemic filling (Pmsf) and central venous pressure (CVP) is the venous return gradient (dVR). The aim of this study is to assess the significance of the Pmsf analogue (Pmsa) and the dVR during a fluid challenge.
  
  
  METHODS
  We performed a prospective observational study in postsurgical patients. Patients were monitored with a central venous catheter, a LiDCO™plus and the Navigator™. A 250-ml intravenous fluid challenge was given over 5 min. A positive response to the fluid challenge was defined as either a stroke volume (SV) or cardiac output increase of greater than 10 %.
  
  
  RESULTS
  A total of 101 fluid challenges were observed in 39 patients. In 43 events (42.6 %) the SV and CO increased by more than 10 %. Pmsa increased similarly during a fluid challenge in responders and non-responders (3.1 ± 1.9 vs. 3.1 ± 1.8, p = 0.9), whereas the dVR increased in responders (1.16 ± 0.8 vs. 0.2 ± 1, p < 0.001) as among non-responders CVP increased along with Pmsa (2.9 ± 1.7 vs. 3.1 ± 1.8, p = 0.15). Resistance to venous return did not change immediately after a fluid challenge. Heart performance (Eh) decreased significantly among non-responders (0.41 ± 0.15 vs. 0.34 ± 0.13, p < 0.001) whereas among responders it did not change when compared with baseline value (0.35 ± 0.15 vs. 0.34 ± 0.12, p = 0.15).
  
  
  CONCLUSIONS
  The changes in Pmsa and dVR measured at the bedside during a fluid challenge are consistent with the cardiovascular model described by Guyton.
authors: Intensive Care Directorate, St George's Healthcare NHS Trust and Medical School, Tooting, London, SW17 0QT, UK. m.cecconi@nhs.net
authors: Maurizio
authors: M
authors: Cecconi
authors: Hollmann D
authors: HD
authors: Aya
authors: Martin
authors: M
authors: Geisen
authors: Claudia
authors: C
authors: Ebm
authors: Nick
authors: N
authors: Fletcher
authors: R Michael
authors: RM
authors: Grounds
authors: Andrew
authors: A
authors: Rhodes
mesh_terms: D000368:Aged; D002302:Cardiac Output; D002496:Central Venous Pressure; D003661:Decision Support Techniques; D003936:Diagnosis, Computer-Assisted; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006439:Hemodynamics; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods*; D011182:Postoperative Care; D011446:Prospective Studies; D012372:ROC Curve; D013318:Stroke Volume
references: J Physiol. 1894 Apr 17;16(3-4):159-318.7
references: 16992163
references: Curr Opin Crit Care. 2011 Jun;17(3):290-5
references: 21508838
references: Crit Care Med. 2007 Jan;35(1):64-8
references: 17080001
references: Intensive Care Med. 2010 Jun;36(6):940-8
references: 20111858
references: Intensive Care Med. 2012 Sep;38(9):1452-60
references: 22584797
references: Crit Care. 2008;12(3):R74
references: 18533029
references: Anesth Analg. 2010 Aug;111(2):464-7
references: 20418537
references: Anesthesiology. 1968 Mar-Apr;29(2):314-26
references: 5635884
references: Crit Care Med. 2006 May;34(5):1333-7
references: 16557164
references: Crit Care Med. 2009 Mar;37(3):912-8
references: 19237896
references: Crit Care Med. 2004 Mar;32(3):691-9
references: 15090949
references: J Physiol. 1914 Sep 8;48(5):357-79
references: 16993262
references: N Engl J Med. 2006 Jun 15;354(24):2564-75
references: 16714767
references: J Clin Neurosci. 2006 Oct;13(8):818-22
references: 16908157
references: Am J Physiol. 1955 Mar;180(3):463-8
references: 14376522
references: Physiol Rev. 1955 Jan;35(1):123-9
references: 14356924
references: Am J Physiol. 1958 Aug;194(2):263-7
references: 13559460
references: Anesth Analg. 1979 Mar-Apr;58(2):124-32
references: 571235
references: J Clin Monit Comput. 2008 Dec;22(6):391-400
references: 19002596
references: J Crit Care. 1994 Jun;9(2):124-33
references: 7920979
references: Anesth Analg. 2009 Apr;108(4):1209-11
references: 19299788
references: Curr Opin Crit Care. 2005 Jun;11(3):264-70
references: 15928477