Data Collection During Exercise testing

SpO2 – Pulse Ox Advantage: [blank_start]Continuous[blank_end] readings Disadvantage: Inaccurate with poor perfusion or [blank_start]motion[blank_end] artifact Terminate test if SpO2 is <[blank_start]85[blank_end]%

Tidal Volume Vt = VE / RR Normal: [blank_start]5[blank_end] ml per kg of body weight At low/moderate workloads total ventilation will increase by increasing [blank_start]tidal volume[blank_end] At high workloads total ventilation increases by increasing [blank_start]respiratory rate[blank_end]

Frequency of Breathing (# of accumulated breathes) / testing time in minutes = RR Normal at rest: [blank_start]8[blank_end] – [blank_start]12[blank_end]

Minute Ventilation Vt x RR = Ve Normal Resting: [blank_start]5[blank_end] – [blank_start]10[blank_end] L/min Normal Exercising: [blank_start]100[blank_end] – [blank_start]200[blank_end] L/min Maximum minute ventilation = FEV1 x [blank_start]35[blank_end] Should be able to reach [blank_start]70[blank_end]% of max If max minute ventilation is [blank_start]reached[blank_end] this indicates a primary ventilator limitation to exercise.

Alveolar Minute Ventilation = (Vt-[blank_start]VD[blank_end]) x [blank_start]RR[blank_end] or = VE – (VD x RR) Estimated anatomical deadspace is [blank_start]1[blank_end] ml per lb of body weight

O2 Consumption – (VO2) Amount of O2 [blank_start]consumed[blank_end] in L/min Normal at Rest: [blank_start].25[blank_end] L/min Normal Exercising: Up to [blank_start]4[blank_end] L/min Requires inline gas analyzers to measure O2%, an FeCO2 [blank_start]analyzer[blank_end] and a spirometer

O2 Pulse Volume of O2 consumer per [blank_start]heartbeat[blank_end] (VO2/HR) x [blank_start]1000[blank_end] = mL O2/beat Normal Resting: [blank_start]2.5[blank_end] – [blank_start]4[blank_end] mL O2/beat Normal Exercising: [blank_start]10[blank_end] – [blank_start]15[blank_end] mL O2/beat Significance: O2 pulse that doesn’t increase with high HR indicates [blank_start]heart[blank_end] disease Tachycardia at rest will [blank_start]decrease[blank_end] O2 pulse Arrhythmia will [blank_start]increase[blank_end] O2 pulse Beta Blockers will [blank_start]increase[blank_end] O2 pulse Plateau in O2 consumption will [blank_start]decrease[blank_end] O2 pulse

CO2 Production (VCO2) – Amount of CO2 [blank_start]produced[blank_end] in L/min Normal resting: [blank_start].2[blank_end] L/min Normal exercising: Up to [blank_start]4[blank_end] l/min Gives indication of [blank_start]metabolic[blank_end] status FeCO2 x [blank_start]VE[blank_end] = VCO2

PH pH will decrease due to increased [blank_start]PaCO2[blank_end] and [blank_start]lactic[blank_end] acid In normal patients, pH will not decrease until [blank_start]anaerobic threshold[blank_end] is reached.

Alveolar-Arterial O2 Tension, A-a Gradient, PAO2-PaO2 or P(A-a)O2 PaO2 <[blank_start]50[blank_end] means you should terminate the tes Normal P(A-a)O2 On RA: [blank_start]10[blank_end]-[blank_start]20[blank_end] On 100% O2: Less than [blank_start]100[blank_end] Increase in P(A-a)O2 with [blank_start]decrease[blank_end] in PaO2: Increased right to left [blank_start]shunt[blank_end], [blank_start]V/Q[blank_end] mismatch, [blank_start]diffusion[blank_end] defects Use Supplemental O2 if [blank_start]hypoxemic[blank_end] at rest.

Ventilatory Equivalent for O2 (Ve/VO2) Relationship of Ve to [blank_start]workload[blank_end] performed (VO2) Gives indication of [blank_start]efficiency[blank_end] of gas exchange at different workloads [blank_start]Ve[blank_end](BTPS)/[blank_start]VO2[blank_end](STPD) Normal at rest and low/moderate workloads: [blank_start]20[blank_end] – [blank_start]30[blank_end] L/LVO2 Increase in Ve out of proportion to [blank_start]increase[blank_end] in VO2 means [blank_start]pulmonary[blank_end] disease Increase in Ve/VO2 at rest means [blank_start]hyperventilation[blank_end]

Ventilatory Equivalent for CO2 (Ve/VCO2) Relationship of Ve to [blank_start]VCO2[blank_end] [blank_start]Ve[blank_end](BTPS)/[blank_start]VCO2[blank_end](STPD) Normal: [blank_start]25[blank_end]-[blank_start]35[blank_end] L/LCO2 Can be used to determine maximum tolerable workloads for patients with [blank_start]pulmonary[blank_end] disease Anaerobic threshold reached when Ve/VCO2 is constant but Ve/VO2 [blank_start]increases[blank_end]

PaCO2/ETCO2 Used to calculate [blank_start]VD/Vt[blank_end] Normal VD/Vt = [blank_start].2[blank_end] - [blank_start].4[blank_end] at rest [blank_start]Decreases[blank_end] with exercise Moderate Workloads: PaCO2 is constant, [blank_start]PeCO2[blank_end] increases High Workloads: Metabolic [blank_start]acidosis[blank_end] due to lactic acid production

Respiratory Exchange Ratio (RER) Relationship of O2 consumption and CO2 production at the mouth which represents gas exchange in the lungs RER = [blank_start]VCO2[blank_end]/[blank_start]VO2[blank_end] or (FeCO2xVe)/VO2 Normal at rest: [blank_start].85[blank_end] Normal with Exercise: [blank_start]1.0[blank_end] or greater RER should [blank_start]increase[blank_end] at anaerobic threshold

Hemodynamics Cardiac Monitor – Simplest way to monitor heart rate and rhythm. Normal HR: [blank_start]60[blank_end] – [blank_start]100[blank_end]

Blood Pressure: Equipment: Indwelling catheter and pressure transducer You can also take BP [blank_start]manually[blank_end] Normal Values: Systolic: [blank_start]120[blank_end] Diastolic: [blank_start]80[blank_end] Mean: [blank_start]93[blank_end] MAP = (2x [blank_start]diastolic[blank_end] + [blank_start]systolic[blank_end])/3 Heart spends twice as much time in [blank_start]diastole[blank_end].

Central Venous Pressure (CVP) Used to Monitor systemic [blank_start]venous[blank_end] drainage and function of the [blank_start]right[blank_end] heart. Catheter is located in [blank_start]right[blank_end] [blank_start]atria[blank_end]. Normal: [blank_start]2[blank_end]-[blank_start]6[blank_end] mmHG or [blank_start]4[blank_end]-[blank_start]12[blank_end] cmH2O CVP – AKA: Right [blank_start]Atrial[blank_end] Pressure R Atriral filling pressue [blank_start]Right[blank_end] side preload Right ventricular [blank_start]filling[blank_end] pressure [blank_start]Right[blank_end] ventricular end [blank_start]diastolic[blank_end] pressure

Pulmonary Artery pressure (PAP) PAP and PCWP are measure with [blank_start]balloon[blank_end] tipped [blank_start]flow[blank_end] directed pulmonary artery catheter (Swan Ganz) Catheter is directed through the [blank_start]right[blank_end] side of the heart and positioned in [blank_start]pulmonary artery[blank_end] Normal PAP: Systolic: [blank_start]25[blank_end] mmHg Diastolic: [blank_start]8[blank_end] mmHg Mean: [blank_start]14[blank_end] mmHg Mixed [blank_start]venous[blank_end] samples should be drawn from pulmonary artery. If blood is bright red the balloon was [blank_start]inflated[blank_end] or wedged if PaCO2 = PaO2

Pulmonary Capillary Wedge Pressure (PCWP) When balloon is [blank_start]inflated[blank_end] it will measure PCWP Normal = [blank_start]8[blank_end] mmHg (4-12) Estimates pulmonary [blank_start]venous[blank_end] drainage back to [blank_start]left[blank_end] heart PCWP aka: [blank_start]Left[blank_end] atrial pressure Left atrial [blank_start]filling[blank_end] pressure Left side preload [blank_start]Left[blank_end] ventricular filling pressure Left [blank_start]ventricular[blank_end] end diastolic pressure

Cardiac Output (Qt) Output of left [blank_start]ventricle[blank_end] to systemic [blank_start]arterial[blank_end] circulation Normal Qt is [blank_start]5[blank_end] L/min (4-8) depending on body size Fick equation: Qt = [blank_start]VO2[blank_end]/(C(a-v)O2x [blank_start]10[blank_end]) If stroke volume is known: Qt= [blank_start]HR[blank_end] x [blank_start]Stroke Volume[blank_end] Thermal Dilution: Cold saline injection Cardiac Index = [blank_start]Qt[blank_end] /([blank_start]body surface area[blank_end]) Normal: [blank_start]2.5[blank_end] – [blank_start]4[blank_end] lpm/m2

CVP: ↑ ↑ PAP: N ↓ PCWP: N ↓ QT: N = [blank_start]Right[blank_end] Heart Failure, [blank_start]Cor[blank_end] Pulmonale, [blank_start]Tricuspid[blank_end] Valve Stenosis

CVP: ↑ PAP: ↑↑ PCWP: N ↓ QT: N = [blank_start]Lung[blank_end] Disorders, Pulm [blank_start]Embolism[blank_end], [blank_start]Pulm[blank_end] HTN, Air [blank_start]Embolism[blank_end]

CVP: N PAP: ↑ PCWP: ↑↑ QT:↓ = [blank_start]Left[blank_end] heart Failure, [blank_start]mitral[blank_end] valve stenosis, [blank_start]CHF[blank_end], High [blank_start]PEEP[blank_end] effects

CVP: ↑↑ PAP: ↑ PCWP: ↑ QT: ↑ = [blank_start]Hypervolemia[blank_end] CVP: ↓↓ PAP: ↓ PCWP: ↓ QT: ↓ = [blank_start]Hypovolemia[blank_end]

Systemic Vascular resistance (SVR) : Pressure gradient across [blank_start]systemic[blank_end] circulation divided by [blank_start]Qt[blank_end] SVR = ([blank_start]MAP[blank_end] – [blank_start]CVP[blank_end]) / Qt Normal: <[blank_start]20[blank_end] mmHg/l/min or 1600 Dynes/sec SVR is [blank_start]increased[blank_end] with systemic hypertension or vasoconstriction

Pulmonary Vascular Resistance (PVR): Pressure gradient across [blank_start]pulmonary[blank_end] circulation divided by Qt PVR = ([blank_start]MPAP[blank_end] – [blank_start]PCWP[blank_end]) / Qt Normal: < [blank_start]2.5[blank_end] mmHg/L/mi or 200 Dynes/sec PVR is increased with [blank_start]hypoxia[blank_end], [blank_start]pulmonary[blank_end] HTN, [blank_start]lung[blank_end] disease

Metabolic Measurements [blank_start]Breath[blank_end]-by-breath measurement Determines [blank_start]metabolic[blank_end] measurements of VO2, VCO2, RR, Vt Requires use of one way valve, [blank_start]pneumotach[blank_end] and continuous sampling of gases. Mixing Chamber Pt inspires room air via 1 way valve then exhales into gas mixing chamber with [blank_start]baffles[blank_end] to completely mix the gases [blank_start]O2[blank_end] and [blank_start]CO2[blank_end] concentration are measured.