This 22-year-old shipyard apprentice machinist was evaluated because of complaints of dyspnoea. He stated that he had been unable to play a full game of football (soccer) for the last 3 years and that he gets out of breath and has to stop after climbing three to four flights of stairs on shipboard. He never smoked. He denied cough, chest pain, oedema, or other symptoms. Physical, X-rays, and laboratory examinations were normal.
The patient performed exercise on a cycle ergometer. He pedalled at 60rpm without added load for 3minutes. The work rate was then increased 20W per minute to his symptom-limited maximum. He stopped exercise because of general fatigue. Resting and exercise ECGs were normal.
Selected Respiratory Function Data – were all within normal limits
|Hb, g/L||[130-165 g/L]||154|
|DLCO, ml/mm HG/Min||22.4||29.8|
Selected Exercise Data
|RER at end||1.22|
|VO2peak (max) (mL/kg/min)||42.5||46.3 (109%)|
|VO2 at AT||28.4 (67%)|
|VE/VCO at AT||25|
|Maximum VE, L.min||209.0||108.4 (52%)|
|BP (rest, max)||110/70; 180/60|
|ECG (rest, max)||82; 194 (98%)|
|Vd/Vt||0.28 – 0.09|
|O2 pulse||14 – 18|
Is the exercise capacity reduced?
No, when looking at panel 3: VO2 and VCO2 vs work rate.
Assess VO2 max/peak first?
– low, normal, high?
Assess VO2 response
– normal = linear increase with work rate @ 20ml/min/watt
Assess VCO2 response
– increases linearly (y=1<) with VO2 up to lactic acidosis (AT)
– More rapid increase after AT
If it was reduced it could have been any disorder, yet it wasn’t and all was within normal limits.
Wasserman et al: Chapter 8 refer to the Principles of Interpretation: A flowchart Approach.
Principles of Exercise Testing and Interpretation: including Pathophysiology and Clinical Applications; p. 183.
Referring to flowchart 1,
Peak VO2 and the anaerobic threshold are within normal limits.
See Flowchart 2, the ECG and O2 pulse at peak are normal, the patient is NOT obese, the results for this patient are all normal, and his symptoms could be related to a lack of fitness.