Swan-Ganz Catheter

History of the Swan-Ganz Catheter

  • 1970: the pulmonary artery (PA) catheter was first developed by Swan and Ganz
    • The PA catheter was originally designed to provide physiologic information about cardiac function

Indications for Swan-Ganz Catheterization

General Comments

Reasons that Use of the Swan-Ganz Catheter Has Diminished

  • Risk of Swan-Ganz Catheterization
  • Variable Technical Proficiency (from Center to Center) in Swan-Ganz Catheter Management and Data Interpretation
  • Static Variables Obtained from the Swan-Ganz Catheter Poorly Predict Intravenous Fluid Responsiveness
    • Study of Hemodynamic Variables in Predicting Fluid Responsiveness (Chest, 2002) [MEDLINE]: static hemodynamic parameters were poorly predictive of fluid responsiveness
  • Studies Have Not Consistently Demonstrated Clinical Benefit from Use of the Swan-Ganz Catheter
    • French PA Catheter Study of Swan-Ganz Catheter in Shock and ARDS (JAMA, 2003) [MEDLINE]
      • Early Swan-Ganz Catheter Use Did Not Impact the Mortality in Shock and ARDS
    • Meta-Analysis of Swan-Ganz Catheter Trials in the ICU (JAMA, 2005) [MEDLINE]
      • Swan-Ganz Catheter Did Not Impact the Mortality or Number of Hospital Days
    • PAC-Man Study of Swan-Ganz Catheter Use in the ICU (Lancet, 2005) [MEDLINE]
      • Swan-Ganz Catheter Did Not Impact the Mortality Rate
    • Study of Swan-Ganz Catheter vs CVC in Acute Lung Injury (NEJM, 2006) [MEDLINE]
      • Swan-Ganz Catheter Did Not Improve Mortality Rate vs Using a CVC, But Was Associated with an Increased Risk of Complications

Determination of Intracardiac Shunt (see Intracardiac and Extracardiac Shunt, [[Intracardiac and Extracardiac Shunt]])

  • Rationale: utilizing oxygen saturations to detect a “step-up” (due to a left -> right intracardiac shunt)

Diagnosis and Monitoring of Pulmonary Hypertension (see Pulmonary Hypertension, [[Pulmonary Hypertension]])

  • xxx

Differentiation of Cardiogenic vs Non-Cardiogenic Pulmonary Edema (see Pulmonary Edema, [[Pulmonary Edema]])

  • Clinical Efficacy
    • French PA Catheter Study of Swan-Ganz Catheter in Shock and ARDS (JAMA, 2003) [MEDLINE]
      • Early Swan-Ganz Catheter Use Did Not Impact the Mortality in Shock and ARDS
    • Study of Swan-Ganz Catheter vs CVC in Acute Lung Injury (NEJM, 2006) [MEDLINE]
      • Swan-Ganz Catheter Did Not Improve Mortality Rate vs Using a CVC, But Was Associated with an Increased Risk of Complications
  • Recommendations
    • However, the Swan-Ganz Catheter is Not Recommended for the Routine Management of Sepsis-Associated ARDS (2012 Surviving Sepsis Guidelines; Crit Care Med, 2013) [MEDLINE]

Differentiation of Hypotensive/Shock States (see Hypotension, [[Hypotension]])

  • Hypovolemic Shock (see Hypovolemic Shock, [[Hypovolemic Shock]])
  • Hemorrhagic Shock (see Hemorrhagic Shock, [[Hemorrhagic Shock]])
  • Distributive Shock
    • Septic Shock (see Sepsis, [[Sepsis]])
    • Systemic Inflammatory Response Syndrome (SIRS)
    • Anaphylactic Shock (see Anaphylaxis, [[Anaphylaxis]])
    • Endocrine/Nutritional Deficiency-Associated Hypotension/Shock
    • Hematologic Disease-Associated Hypotension/Shock
    • Neurogenic Shock (see Neurogenic Shock, [[Neurogenic Shock]])
    • Drug/Toxin-Associated Hypotension/Shock
    • Other Types of Distributive Shock
  • Cardiogenic Shock/Severe Congestive Heart Failure (CHF) (see Cardiogenic Shock, [[Cardiogenic Shock]])
    • Arrhythmogenic
    • Cardiomyopathic
    • Mechanical
  • Obstructive Shock
    • Mechanical
    • Pulmonary Vascular

Multiple Trauma/Burns (see Burns, [[Burns]])

  • xxx

Perioperative Optimization/Operative Management of Hemodynamics for High-Risk Surgery (see Hemodynamics, [[Hemodynamics]])

  • Surgical Procedures: especially in patients with suboptimal cardiac function
    • Cardiac Surgery
    • Pneumonectomy
  • Clinical Efficacy
    • Systematic Review and Meta-Analysis of Swan-Ganz Catheter in the Outcome of Moderate to High-Risk Surgical Patients (Anesth Analg, 2011) [MEDLINE]
      • Preemptive Strategy of Swan-Ganz Catheter Hemodynamic Monitoring and Coupled Therapy Decreased Surgical Mortality and Morbidity

Research Purposes

  • xxx

Ventricular Pacing

  • When Using a Swan-Ganz Catheter with Pacing Capabilities

General Principles of the Swan-Ganz Catheter

  • Swan-Ganz Catheter is Used to Measure Hemodynamic Parameters (see Hemodynamics, [[Hemodynamics]])
    • Cardiac Output (CO)
    • Pulmonary Artery-Systolic Pressure (PA-Systolic Pressure) and Pulmonary Artery-Diastolic Pressure (PA-Diastolic Pressure): these are used to derive the pulmonary artery-mean pressure (PA-Mean Pressure)
    • Central Venous Pressure (CVP)
    • Pulmonary Capillary Wedge Pressure (PCWP)
  • Swan-Ganz Catheter-Derived Data and Mean Arterial Pressure are Subsequently Utilized to Calculate Hemodynamic Parameters (see Hemodynamics, [[Hemodynamics]])
    • Systemic Vascular Resistance (SVR)
    • Pulmonary Vascular Resistance (PVR)

Swan-Ganz Catheter Structure

  • Catheter and Lumens: PA catheter is an approximate 110 cm radiopaque polyvinylchloride catheter with 2-3 internal lumens
    • The distal lumen terminates at the tip of the catheter (Distal Port)
    • The proximal lumen terminates at about 30 cm from the tip (Proximal Port)
    • An optional third lumen terminates at about 20-30 cm from the tip
  • Thermistor: PA catheter has a thermistor device approximately 3-5 cm from the tip
    • Thermistor measures temperature and allows calculation of cardiac output (by thermodilution technique) and sometimes RV ejection fraction
  • Balloon: 1.5 inflatable balloon is located near the tip of the catheter
    • Balloon guides passage and occludes the pulmonary capillary when catheter is “wedged”

Circulatory Anatomy in Relation to Placement of the Swan-Ganz Catheter

SWANPATH


Pressure Transduction with the Swan-Ganz Catheter

  • Lumens of PA Catheter: connected to pressure transducers, which provide continuous pressure tracings of RA pressure and PA pressure
  • Balloon Inflation (“wedging the catheter”): causes migration of catheter tip into a pulmonary capillary -> PA pressure waveform changes to the Pulmonary Capillary Wedge Pressure (PCWP) waveform

BALLOON


Pressure Waveforms with the Swan-Ganz Catheter

PCWP

  • Normal Pressure Values
    • RA/CVP: 0-8 mm Hg
    • RV: 15-30 mm Hg/ 0-8 mm Hg
    • PA-Systolic: 15-30 mm Hg
    • PA-Diastolic: 4-12 mm Hg
    • Mean PA: 9-16 mm Hg
    • PCWP: 2-12 mm Hg
      • By convention, PCWP is measured at end-expiration
        • For a patient not on ventilator: this will be at the highest point in the respiratory cycle (since intrathoracic pressure decreases during inspiration during spontaneous ventilation)
        • For a patient on ventilator (“vent = valley”): this will be at the lowest point in the respiratory cycle (since intrathoracic pressure increases during inspiration on positive-pressure ventilation)
      • Note: PCWP is always less than mean PA pressure and is usually less than the PA-Diastolic pressure (unless large “v” waves are present due to mitral regurgitation, etc)

Measurement of Cardiac Output (CO) with the Swan-Ganz Catheter

Thermodilution Method

  • Technique: utilizes thermistor on end of Swan-Ganz catheter to measure clearance of cold, injected saline (clearance is proportional to the blood flow rate) -> thermodilution method (based on principles developed by Fick in the late Nineteenth Century) utilizes the temperature change after injection as a function of CO
    • When the CO is high, the injectate is rapidly dispersed and the area under the curve is small -> therefore, area under the thermodilution curve is inversely related to the CO value
  • Variability: variability in CO calculations by thermodilution is approximately 10% (thus, changes in CO should generally be on the order of 15% to be regarded as valid)
  • Falsely Decreased CO
    • Tricuspid Regurgitation (TR) (see Tricuspid Regurgitation, [[Tricuspid Regurgitation]]): local “recirculation” of injectate -> mimics slow injectate clearance
    • Pulmonic Regurgitation (see Pulmonic Regurgitation, [[Pulmonic Regurgitation]]): same as for TR
    • Erroneously High Injectate Volume
  • Falsely Increased CO
    • Intracardiac Shunt (in either direction) (see Intracardiac and Extracardiac Shunt, [[Intracardiac and Extracardiac Shunt]]): alters curve and makes CO calculation less accurate
    • Low Cardiac Output State: injectate can disperse into the surrounding tissue, mimics rapid injectate clearance
    • Erroneously Low Injectate Volume
  • Early Recirculation on Thermodilution Curve: suggests presence of L->R intracardiac shunt
  • “Continuous” Cardiac Output Measurement: PA catheters with capability to measure CO “continuously” (actually averages the CO over a few minute window) are commercially available

Fick Method

  • Technique: utilizes arterial-venous (A-V O2) difference
    • Based on arterial and mixed venous saturations
  • Method: based on the concept of the extraction ratio
    • Therefore, changes in peripheral extraction may falsely be interpreted as changes in the CO

Adverse Effects/Complications of Swan-Ganz Catheterization

  • Pulmonary Infarction (see Pulmonary Infarction, [[Pulmonary Infarction]]): due to prolonged balloon inflation
    • Prevent by always deflating the balloon after wedging
  • Pulmonary Artery Rupture (see Pulmonary Artery Rupture, [[Pulmonary Artery Rupture]]): due to balloon overinflation
    • Prevent by careful inflation with 1.5 ml of air (most PA catheters come with a PCWP syringe which has a built-in “lock” at 1.5 ml)
  • Air Embolism (see Air Embolism, [[Air Embolism]]): due to balloon rupture
    • Prevent by avoiding balloon overinflation
  • Arrhythmia: due to catheter irritation of myocardium
  • Catheter Knotting in Ventricle: prevent by always monitoring length of insertion while floating catheter
  • Infection
  • Endocardial/Valve Damage
  • Specific Complications of Central Venous Catheterization (see Central Venous Catheter, [[Central Venous Catheter]])

References

  • Inaccuracy of cardiac output by thermodilution during acute tricuspid regurgitation. Ann Thorac Surg 1992; 53:706-708 [MEDLINE]
  • The thermodilution method for the clinical assessment of cardiac output. Intensive Care Med 1995; 21:691-697 [MEDLINE]
  • The effectiveness of right heart catheterization in the initial care of critically ill patients. SUPPORT Investigators. JAMA 1996; 276:889–897 [MEDLINE]
  • Magder S. Cardiac output. In: Tobin MS, ed. Principles and practice of intensive care monitoring. New York: McGraw-Hill, 1998; 797-810
  • A randomised, controlled trial of the pulmonary artery catheter in critically ill patients. Intensive Care Med 2002; 28:256–264 [MEDLINE]
  • Predicting fluid responsiveness in ICU patients: A critical analysis of the evidence. Chest 2002; 121:2000–2008 [MEDLINE]
  • French Pulmonary Artery Catheter Study Group: Early use of the pulmonary artery catheter and outcomes in patients with shock and acute respiratory distress syndrome: A randomized controlled trial. JAMA 2003; 290:2713–2720 [MEDLINE]
  • Impact of the pulmonary artery catheter in critically ill patients: Meta-analysis of randomized clinical trials. JAMA 2005; 294:1664–1670 [MEDLINE]
  • PAC-Man study collaboration: Assessment of the clinical effectiveness of pulmonary artery catheters in management of patients in intensive care (PAC-Man): A randomised controlled trial. Lancet 2005; 366:472–477 [MEDLINE]
  • Pulmonary-artery versus central venous catheter to guide treatment of acute lung injury. N Engl J Med 2006; 354:2213–2224 [MEDLINE]
  • Does central venous pressure predict fluid responsiveness? A systematic review of the literature and the tale of seven mares. Chest 2008; 134:172–178 [MEDLINE]
  • Fluid therapy in resuscitated sepsis: Less is more. Chest 2008; 133:252–263 [MEDLINE]
  • Functional hemodynamic monitoring and dynamic indices of fluid responsiveness. Minerva Anestesiol 2008; 74:123–135 [MEDLINE]
  • A systematic review and meta-analysis on the use of preemptive hemodynamic intervention to improve postoperative outcomes in moderate and high-risk surgical patients. Anesth Analg 2011; 112:1392–1402 [MEDLINE]
  • Surviving sepsis campaign: international guidelines for management of severe sepsis and septic shock: 2012. Crit Care Med. 2013 Feb;41(2):580-637. doi: 10.1097/CCM.0b013e31827e83af [MEDLINE]