Pulmonary Artery Catheterization

Pulmonary Artery CatheterizationPulmCrit.comPulmonary Artery Catheter HistoryIn 1929, Dr. Warner Forssmann introduced a catheter into his right atriumDrs Andre Cournand & Dickinson Richards developed catheters that could be advanced into the pulmonary arteries aDrs Forssmann, Cournand, and Richards shared the 1956 Nobel Prize in medicine for these discoveriesForssmann W. Die Sondierung des rechten Herzens. Klin Wochenschr. 1929;8: 2085. Pulmonary Artery Catheter HistoryPulmonary Artery Catheter (PAC) aka Swan Ganz catheter first described in 1970 NEJMInitially used for management of acute MIsCatheterization of the Heart in Man with Use of a Flow-Directed Balloon-Tipped CatheterH. J. C. Swan, M.B., Ph.D., F.R.C.P., William Ganz, M.D., C.Sc., James Forrester, M.D., Harold Marcus, M.D., George Diamond, M.D., and David ChonetteN Engl J Med 1970; 283:447-451August 27, 1970DOI: 10.1056/NEJM197008272830902From the Department of Cardiology, Cedars-Sinai Medical Center and the Department of Medicine, University of California, Los AngelesHuge benefit, can be used without flouroscopy

Figure. The double lumen balloon flotation catheter and its placement at the bedside without fluoroscopy and by monitoring intracardiac pressures. Photograph of Drs Swan and Ganz is also shown. RA indicates right atrium; RV, right ventricle; PCW, pulmonary capillary wedge; and PA, pulmonary artery. Figure courtesy of Dr Peter Ganz, Chief of Cardiology at San Francisco General Hospital, University of California, San Francisco.What Dr. Swan & Dr. Ganz didInserted a 5 French double lumen balloon catheter into the RAThe baloon was inflated with 0.8cc of airCarried by blood flow to the right ventricle and PAWhen in smaller branches of PA, baloon inflated fully and wedge obtained

Indications: When to use PACs?Not indicated as routine pulmonary artery catheterization in high-risk cardiac and noncardiac patientsIndicated in patients with cardiogenic shock during supportive therapyIndicated in patients with discordant right and left ventricular failureIndicated in patients with severe chronic heart failure requiring inotropic, vasopressor, and vasodilator therapyIndicated in patients with suspected pseudosepsis (high cardiac output, low systemic vascular resistance, elevated right atrial and pulmonary capillary wedge pressures)Indicated in some patients with potentially reversible systolic heart failure such as fulminant myocarditis and peripartum cardiomyopathyIndicated for the hemodynamic differential diagnosis of pulmonary hypertensionIndicated to assess response to therapy in patients with precapillary and mixed types of pulmonary hypertensionIndicated for the transplantation workupTable. Current Indications for Use of the Swan-Ganz CatheterCirculation January 6/13, 2009 vol. 119 no. 1147-152CirculationJanuary 6/13, 2009 vol. 119 no. 1147-152

PAC seen on X-Ray

ContraindicationsTricuspid or pulmonary valve prosthesis which can be damagedTricuspid or pulmonary valve vegetations which can be dislodgedEndocarditis in generalRight heart mass (be it tumor or clot)The PA CatheterUsually a 4 lumen catheter 110cm lung with a pressure transducer:A temperature thermistor located proximal to balloon to measure pulmonary artery blood temperatureA proximal port located 30 cm from tip for CVP monitoring, fluid and drug administrationDistal port at catheter tip for PAP monitoring+/- Variable infusion port (VIP) for fluid and drug administrationBalloon at catheter tip

The PA CatheterStandard PAC is 7.0, 7.5 or 8.0 French in circumference and 110 cm in length divided in 10 cm intervalsThe kit includes a syringe that can be filled with only 1.5 mL of air to prevent overinflation of the balloonA long plastic sheath that is used to maintain sterility of the PAC as it is advanced and withdrawnCordis/Introducer should be placed prior

Prior to PAC insertion, Connect the distal port (yellow) to the pressure transducerLevel the transducer at the level of the patients heartZero the transducer

Contraindications for PACsTricuspid or pulmonary valve prosthesis which can be damagedTricuspid or pulmonary valve vegetations which can be dislodgedEndocarditis in generalRight heart mass (be it tumor or clot)

Steps to catherizationPlace Cordis in IJ/SubclavianConnect the distal yellow port to pressure transducer - continuous monitoringLevel the transducer at patients heart level and zeroInsert PAC and when at 20cm mark, inflate the baloonAdvance PAC following waveforms until it wedges (usually 45-60 cm*) *unless really big heartRight heart catherization waveforms

More wave formsNormal Values for Cardiac Index and Related MeasurementsMeasurementUnits SDO2 uptake143 14.3 mL/min/m2Arteriovenous O2difference4.1 0.6 dLCardiac index3.5 0.7 L/min/m2Stroke index46 8.1 mL/beat/m2Total systemic resistance1130 178 dynes-sec-cm-5Total pulmonary resistance205 51 dynes-sec-cm-5Pulmonary arteriolar resistance67 23 dynes-sec-cm-5SD = standard deviation.Adapted from Barratt-Boyes BG, Wood EH: Cardiac output and related measurements and pressure values in the right heart and associated vessels, together with an analysis of the hemodynamic response to the inhalation of high oxygen mixtures in healthy subjects. Journal of Laboratory and Clinical Medicine 51:7290, 1958

Calculated VS Measured valuesMeasured valuesQ: 4-8L/minCI: 2.5-4L/minCVP: 2-6mmHgPAWP: 8-12mmHgPAP: 25/10mmHgSvO2: 0.65-0.70Temperature

Derived values use of formula: Q = MAP-CVP/SVRSV: 50-100mL/beatSVI: 25-45mL/beat/m2SVR: 900-1300 dynes-sec/cm5SVRI: 1900-2400 dyne-sec/cm5PVR: 40-150 dyne-sec/cm5PVRI: 120-200 dynes-sec/cm5

Complications of PACsArrhythmiasThrombosis and hemorrhage along the path of the PACIntracardiac knotting of catheterPulmonary hemorrhageInfection - CLABSIIJ/Subclavian stenosisDistal migration of PAC Pulmonary InfarctionPulmonary artery ruptureRight sides EndocarditisRBBB (careful if pre-exisiting LBBB)Air embolism

The complications that may arise directly from the use of the PAC include pulmonary artery rupture, pulmonary artery thrombosis, intra-cardiac knotting of the catheter, pulmonary hemorrhage, right atrial thrombosis, catheter related bloodstream infection, internal jugular/subclavian vein stenosis or thrombosis, atrial and ventricular arrhythmia, electromechanical dissociation and right-sided endocarditis. These risks may not be trivial. A study of 70 critically ill patients demonstrated that 4% died from complications related to the PAC and that between 20 and 30% had major complications related to the PAC

Stewart-Hamilton EquationA bolus of 5-10ml cold 5% dextrose into the right atrium should decrease the temperature in the pulmonary artery.The rate of blood flow is inversely proportional to the change in temperature over timeThus, the mean decrease in temperature is inversely proportional to the cardiac output.The Stewart-Hamilton Equation describes this relationshipYou should take measurements in expiration.You have to take a mean of 3 measurements.The mean has to be 15% different to the previous mean, otherwise it is within the margin of error.The thermodilution cardiac output can vary by 10% from measurement to measurement without any change in the condition of the patient

Thermodilution SH equation

The higher the cardiac output, the faster he blood flow and the shorter and steeper the thermodilution curve. In low cardiac output, the curve is slurred and lazy. Even more so in tricuspid regurgitation.Too much injected cold stuff causes underestimation of cardiac output.Too little injected cold stuff causes overestimation of cardiac output.Room temperature injectate produces less accurate readings, but is safer.Very cold injectate (0-4 degrees) is more accurate, but can induce bradycardia and decreased cardiac output.

Cardiac output and temperature curvesMinimum 3 measurements with 15% difference between

These curves are visibly different in different cardiovascular pathological states:The higher the cardiac output, the faster he blood flow and the shorter and steeper the thermodilution curve. In low cardiac output, the curve is slurred and lazy. Even more so in tricuspid regurgitation.

Some catheter manufacturers have a heating filament near the tip, which means you don't have to bother with intermittent bolus injections; the catheter just does this automatically every 3 or so minutes, and you have a near- continuous cardiac output measurement.Controversies in PAC useIn 1980s, 20-40% of critically ill patients had PACs1996, Connors published prospective Observation study: increased 30 d mortality (OR 1.24), increased cost.2003: Sandham RCT surg pts to usual care vs PAC - more PEs in PAC2005: ESCAPE Trial: In patients with HF, PAC use doesnt increase 6 month mortality or LOS. More adverse effects associated with PAC2006: Cochrane meta-analysis of PACs in ICUs - 5686 pts - 13 RCT - no diff in mortality, LOS, but increased cost in PAC group Connors AF, Speroff T, Dawson NV, Thomas C, Harrell FE, Wagner D, Desbiens N, Goldman L:The effectiveness of right heart catheterization in the initial care of critically ill patients.JAMA 1996, 276:889-897

Binanay C, Califf RM, Hasselblad V, OConnor CM, Shah MR, Sopko G, Stevenson LW, Francis GS, Leier CV, Miller LW: Evaluation study of congestive heart failure and pulmonary artery catheterization effectiveness: the ESCAPE trial.JAMA 2005, 294:1625-1633.

Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE), the primary hypothesis was that for patients with severe heart failure, therapy guided by PAC monitoring and clinical assessment would lead to more days alive and fewer days hospitalized during 6 months compared with therapy guided by clinical assessment alone.Limitations of ThermodilutionAlthough thermodilution is Gold standard:

PAC thermo method underestimates COUnreliable for changes in CO less than 25-30% (fluid responsiveness defined as 15% change in SV)Spontaneous vs Mechanical ventilation affects CO - SV varies as much as 50%Unreliable in Tricuspid Regurgitation and arrythmias) better in transpulmonary thermodilution - longer transit timeYang XX, Critchley LA, Rowlands DK, Fang Z, Huang L: Systematic error of cardiac output measured by bolus thermodilution with a pulmonary artery catheter compared with that measured by an aortic flow probe in a pig model.J Cardiothorac Vasc Anesth 2013.

Multiple studies have shown a poor relationship between the PCWP and circulating blood volume, SV and left ventricular end-diastolic volume

Role of PACDiagnosing patients with PHManaging perioperative patientsIntracardiac shuntsAmniotic fluid embolismPulmonary artery catheterization has been recommended in patients with significant PAH (sPAP>50 mmHg and/or RV enlargement) undergoing a major surgical intervention [81]. While this recommendation is not supported by high quality evidence, it would appear to be logical as the PA pressure is the only reliable hemodynamic parameter derived from the PAC and its use may allow for the rational titration of vasoactive agents.

There is no evidence that the use of the PAC has improved patient outcomes. ReferencesAnna Gawlinski, Measuring Cardiac Output: Intermittent Bolus Thermodilution Method Crit Care Nurse 2004;24:74-78Toshiaki Nishikawa, Shuji Dohi Errors in the measurement of cardiac output by thermodilutionCanadian Journal of Anaesthesia February 1993, Volume 40, Issue 2, pp 142-153