II. Definitions

  1. Central Venous Pressure (CVP)
    1. Grouping of venous pressures that are equivalent to one another
      1. Superior Vena Cava Pressure
      2. Right Atrial Pressure (RAP)
    2. CVP is also equivalent to the right ventricular end diastolic pressure (RVEDP) and Preload
      1. Only if no tricuspid insufficiency
  2. Right Ventricular End-Diastolic Pressure (RVEDP)
    1. Equivalent to CVP (in the absence of tricuspid insufficiency)

III. Images

  1. Cardiac Cycle Volumes and Pressures (Wiggers Diagram)
    1. cvCardiacCycleWiggers.png

IV. Technique: Central Venous Pressure (CVP)

  1. Catheters
    1. Central venous catheter or
    2. Pulmonary artery catheter (Swans-Ganz Catheter) via proximal port in atrium
      1. Contrast with distal port in pulmonary vessels (pulmonary wedge pressure) reflecting left atrial pressure
    3. PICC Lines are not used for CVP measurement due to long length
      1. Theoretically could be used with saline infusion
      2. Black (2000) Crit Care Med 28:3833-36 [PubMed]
  2. Transducer
    1. Fluid-filled device measures pressure readings from catheter
    2. Placed at the same level as the right atrium
      1. Landmarks for the supine patient
        1. Intersection of the fourth intercostal space and the mid-axillary line
      2. Landmarks for the semi-recumbent patient (<60 degrees)
        1. Below the sternal angle by 5 cm (directly down)
  3. Measurement
    1. Record at the end of expiration (when intrathoracic pressure is closest to atmospheric pressure)
    2. CVP varies with respiration (spontaneous and Mechanical Ventilation)
      1. CVP decreases with spontaneous inspiration (decreased intrathoracic pressure)
      2. CVP increases with Mechanical Ventilation (positive pressure increases intrathoracic pressure)

V. Interpretation

  1. Normal Central Venous Pressure (CVP or RAP, Right Atrial Pressure)
    1. Normal CVP 2 to 8 mmHg (some references list 0 to 5 mmHg)
    2. Measurements vary as much as 4 mm Hg in the same patient under the same conditions
      1. CVP change is only significant if changes more than 4 mmHg
  2. Other Normal Right Sided Pressures
    1. Right Ventricular Pressure = 25/2 mmHg
    2. Pulmonary Artery Pressure (PAP) = 25/12 mmHg
    3. Mean Pulmonary Artery Pressures = 16 mmHg
    4. Mean Pulmonary Capillary Wedge Pressure (or left atrial pressure): 9 mmHg
  3. CVP may be increased initially despite significant volume depletion
    1. Consider underlying COPD, Vasoconstriction
    2. Consider increased intrathoracic pressure (Tension Pneumothorax, Positive Pressure Ventilation)
    3. Consider Diastolic Dysfunction with decreased right ventricular compliance (MI, Sepsis, valvular dysfunction)
    4. Peristently increased CVP suggests adequate volume replacement or Fluid Overload
  4. CVP that is markedly increased
    1. Fluid Overload (Edematous States such as Congestive Heart Failure, liver failure, Renal Failure)
    2. Cardiac Tamponade
    3. Tension Pneumothorax
    4. Central catheter malposition
  5. CVP that is low with signs of shock and minimally rises with fluid bolus
    1. Continue Fluid Replacement (or Blood Products in the case of Hemorrhagic Shock)
    2. Consider source of ongoing losses
  6. CVP that is decreasing with signs of shock
    1. Aggressively search for ongoing losses (e.g. Hemorrhagic Shock)
    2. Continue Fluid Replacement (or Blood Products in the case of Hemorrhagic Shock)
    3. Vasopressors as needed

VI. Precautions

  1. CVP is an indirect, invasive and often inaccurate surrogate for Ventricular Preload and volume status
    1. Consider Inferior Vena Cava Ultrasound for Volume Status as an alternative
  2. End diastolic pressure (e.g. CVP and Wedge Pressure) correlates poorly with end diastolic volume even in healthy patients
    1. Hence CVP and Wedge Pressure are unreliable markers of ventricular filling and volume status
  3. CVP is falsely elevated with increased intrathoracic pressure (e.g. PPV, PEEP)

VII. References

  1. Marino (2014) ICU Book, 4th Ed Wolters-Kluwer p. 157-9
  2. (2012) ATLS Manual, 9th ed, American College of Surgeons
  3. Killu and Sarani (2016) Fundamental Critical Care Support, p. 93-114

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Related Studies

Ontology: Central venous pressure (C0428640)

Definition (MSHCZE) Venózní tlak měřený v oblasti centrálních žil (např. podklíčkové) při současném zavedení centrálního katetru. Poskytuje cenné informace o stupni hydratace a žilního návratu (patří k základním údajů v intenzivně léčbě těchto stavů). (cit. Velký lékařský slovník online, 2013 http://lekarske.slovniky.cz/ )
Definition (MSH) The blood pressure in the central large VEINS of the body. It is distinguished from peripheral venous pressure which occurs in an extremity.
Concepts Clinical Attribute (T201)
MSH D002496
SnomedCT 71420008
English Central Venous Pressure, Central Venous Pressures, Pressure, Central Venous, Pressures, Central Venous, Venous Pressure, Central, Venous Pressures, Central, Central venous pulse pressure, central pressure venous, central venous pressures, central venous pressure, CVP - Central venous pressure, Central venous pressure (observable entity), Central venous pressure
Swedish Centralt ventryck
Czech centrální venózní tlak, centrální žilní tlak
Finnish Keskuslaskimopaine
French PVC (Pression Veineuse Centrale), Pression veineuse centrale
Japanese 中心静脈圧
Spanish presión central del pulso venoso, presión venosa central (entidad observable), presión venosa central, Presión Venosa Central
Polish Ciśnienie żylne ośrodkowe, Ośrodkowe ciśnienie żylne
Norwegian Sentralt venetrykk
German Venendruck, zentraler, Zentraler Venendruck
Italian Pressione venosa centrale
Dutch Centraal-veneuze druk, Druk, centraal-veneuze
Portuguese Pressão Venosa Central

Ontology: Right atrial pressure (C0456165)

Concepts Laboratory or Test Result (T034)
SnomedCT 276755008
English right atrial pressure, atrial pressures right, RA - Right atrial pressure, Right atrial pressure, RAP - Right atrial pressure, Right atrial pressure (observable entity)
Spanish presión de aurícula derecha (entidad observable), presión de aurícula derecha

Ontology: Right ventricular end-diastolic pressure (C0456183)

Concepts Laboratory or Test Result (T034)
SnomedCT 276774000
English RVEDP-Rt ventric end-dias pres, Right ventric end-diast press, RVEDP - Right ventricular end-diastolic pressure, Right ventricular end-diastolic pressure, Right ventricular end-diastolic pressure (observable entity)
Spanish presión de fin de diástole del ventrículo derecho (entidad observable), presión de fin de diástole del ventrículo derecho