Lactate is a very important marker in critical care. It’s very useful as a measure in trauma patients, septic patients and other critical care patients, high values indicating inadequate oxygen delivery to tissue. This is also naturally occuring in healthy subjects during intense workloads that requires an amount of anaerobic work. I’ve often wondered how high lactate gets in healthy subjects. Here’s an answer from a study on alpine skiers.
Elite alpine skiers have an intense workload during the few minutes they race down the mountain. Much of the race is spent in the crouched position with isometric muscle contraction fighting the bumps and vibrations from the snow as they’re racing high speed towards the bottom of the hill. Not only is it an intense load on the system, but it’s also one you can’t stop until you get to the bottom. It pushes your anaerobic capacity to the max.
In this study, elite alpine skiers had a blood lactate concentration averaging 9 to 13 mmol/L following a race.
An average blood lactate of 9-13(!!) I never see this kind of lactate in even the sickest patients, unless they’re in cardiac arrest!
Of course, these athletes and critical patients are not comparable groups in any way. But it’s just a great illustration of how lactate production during anaerobic work is a very natural occurrence. Your lactate goes up even as you’re chasing the bus. In healthy persons, the lactate is quickly cleared from the system when the intense work is done. And our aim is to get our critical patients to clear their lactate, as a sign that they’re getting healthier as well.