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Troubleshoot — Cannot Desaturate

Some cus­tomers have issues desat­u­rat­ing.  This is near­ly always because of spe­cif­ic issues with user phys­i­ol­o­gy. As a rule, only well-trained ath­letes and con­di­tioned users will have pre­dictable desat­u­ra­tion responses.

See Also: Train­ing Desat­u­ra­tion Patterns

This arti­cle is split into two sec­tions. The first sec­tion explains com­mon issues with the user. The sec­ond sec­tion is a check­list for issues that may occur over time. 

There are a hand­ful of issues that may make a new user think LiveO2 isn’t work­ing prop­er­ly because a pulse oxime­ter does not read­i­ly show a decrease in oxy­gen con­cen­tra­tion in the blood while using ‑O2. This often leaves the user won­der­ing what is happening…

If the issue is with LiveO2, it’s easy to detect and cor­rect the prob­lems. When the issue is part of the user phys­i­ol­o­gy — It’s more dif­fi­cult to under­stand but still easy to test:

  • If the user ‘feels extra chal­lenge’ on ‑O2 — the sys­tem is work­ing properly. 

User-specific desaturation problems

Most of the time users can­not desat­u­rate because of one of these reasons.

#1: User metabolism challenge that interferes with blood oxygen exchange or poor hand circulation

Many new LiveO2 users have meta­bol­ic issues that inter­fere with blood gas exchange. There are three com­mon dysfunctions:

  • Cap­il­lary shunt­ing. These users exhib­it unusu­al­ly high O2 sat­u­ra­tion lev­els because issues flow restric­tions in cap­il­lary beds shunt blood around the tis­sue. Oxy­gen lev­els remain high because oxy­gen nev­er reach­es tis­sue and is underused.
  • Nutri­ent defi­cien­cies. The body requires suf­fi­cient amounts of B‑vitamins to affect gas trans­fer to the tis­sue. Defi­cien­cies inhib­it trans­fer and may inhib­it the abil­i­ty to sat­u­rate or desaturate.

These issues often hap­pen togeth­er. Each ele­ment reduces the user’s appar­ent abil­i­ty to desat­u­rate as read by a pulse oximeter.

  • Shunt­ing pre­vents oxy­gen from leav­ing the blood
  • Nutri­ent defi­cien­cies pre­vent oxy­gen from leav­ing the blood
  • Car­bon monox­ide and oxy­gen are indis­tin­guish­able by a pulse oximeter.

But… No mat­ter how these fac­tors inter­fere with the pulse oxime­ter there is a very effec­tive test.

The users will feel the ‑O2 chal­lenge. Inef­fi­cient res­pi­ra­tion makes users very sen­si­tive to reduced oxy­gen lev­els. That leads us to…

The simplest test for a new user

If your users feel extra dif­fi­cul­ty on the ‑O2 set­ting then this is a strong and reli­able indi­ca­tor that the sys­tem is work­ing properly. 

Most users will slow down on ‑O2 and speed up on +O2. Users with com­pro­mised res­pi­ra­tion will quick­ly notice the decrease in oxy­gen from 75% to 14% for LiveO2 AC

#2 User was exposed to Carbon Monoxide

Car­bon monox­ide has a high­er affin­i­ty for hemo­glo­bin than oxy­gen and may be due to envi­ron­men­tal expo­sure or inter­nal­ly gen­er­at­ed as a result of dys­func­tion­al cel­lu­lar res­pi­ra­tion. Pulse oxime­ters can­not dis­tin­guish blood-car­ry­ing car­bon monox­ide from blood sat­u­rat­ed with oxy­gen. Users with car­bon monox­ide will not desaturate. 

Car­bon monox­ide binds to hemo­glo­bin sites just like oxy­gen. Pulse oxime­ters can­not dis­tin­guish hemo­glo­bin with Car­bon Monox­ide from Oxy­gen. Car­bon monox­ide can be envi­ron­men­tal or endo­genic (from inside the body). Car­bon monox­ide binds to hemo­glo­bin about 240x more read­i­ly than oxygen.

Car­bon monox­ide in the blood will pre­vent the pulse oxime­ter from read­ing cor­rect­ly. It will read as though the blood is sat­u­rat­ed with oxy­gen when it is not. We have also seen indi­vid­u­als who appear to have car­bon monox­ide tox­i­c­i­ty when there was no known expo­sure to car­bon monox­ide as though it was endoge­nous (made inside the body) from inef­fi­cient metabolism.

When train­ing with LiveO2 — the high bind­ing affin­i­ty of car­bon monox­ide makes it look like the per­son can­not desaturate. 

See Also:


Car­boxy­he­mo­glo­bin is pro­duced by the bind­ing of car­bon monox­ide (CO) to hemo­glo­bin. CO is gen­er­at­ed dur­ing incom­plete com­bus­tion of organ­ic prod­ucts and has tox­ic effect because it com­petes with oxy­gen for the same bind­ing site in the Fe2+ of Hb. Hemo­glo­bin bound to CO is unable to trans­port O2. Hb has a 210-fold greater affin­i­ty for car­bon monox­ide than for oxy­gen, which explains the extra­or­di­nary tox­i­c­i­ty of CO even when its con­cen­tra­tion in the inspired air is rel­a­tive­ly low. For exam­ple, breath­ing air con­tain­ing 0.02% CO for 2 h caus­es symp­toms, such as headache and nau­sea. A con­cen­tra­tion of 0.1% pro­duces loss of con­scious­ness with­in 1 h and death by asphyx­ia in only 4 h. Car exhaust gas­es con­tain between 4% and 7% CO and tox­ic con­cen­tra­tions are read­i­ly achieved in poor­ly ven­ti­lat­ed envi­ron­ments (garages). Car­boxy­he­mo­glo­bin has a cher­ry red col­or. For that rea­son, sub­jects intox­i­cat­ed with CO show appar­ent­ly “healthy” red­dish lips and cheeks.

Con­tact your train­er for sup­port. We have spe­cial­ized pro­to­cols to expe­dite car­bon monox­ide release from hemoglobin.

Physical Failure Checklist

Here are phys­i­cal fail­ures that can result in fail­ure to desaturate.

#1: Enthusiastic user cranked the oxygen flow meter too high

The oxy­gen flow meter should be set to 10 LPM or maybe slight­ly above. Some new users will open the oxy­gen flow to max­i­mum and the ball will be at the com­plete top of the oxy­gen flow range. This error will also cause the air sep­a­ra­tor to dis­play an amber light that will nev­er go off.

This push­es so much air through the air sep­a­ra­tor that both the oxy­gen con­cen­tra­tion in +O2 is low, and the oxy­gen con­cen­tra­tion in the ‑O2 is high. The extra oxy­gen at the ‑O2 set­ting often pre­vents users from desaturating.

This push­es so much air through the air sep­a­ra­tor that both the oxy­gen con­cen­tra­tion in +O2 is low, and the oxy­gen con­cen­tra­tion in the ‑O2 is high. The extra oxy­gen at the ‑O2 set­ting often pre­vents users from desaturating.

#3: Ripped breather hose

This occurs when the breather hose is pulled so hard the mem­brane between the ribs rips and allows room air to leak in when the user inhales.

This leak allows room air to dilute both the +O2 and ‑O2 air which inhibits both oxy­gen sat­u­ra­tion and oxy­gen desaturation. 

The best way to test this is to care­ful­ly inspect the hose to assure the mem­brane between the ribs is intact for the entire length of the hose. 

Tuto­r­i­al: Inspect and replace a dam­aged breather hose

If you doubt your inspec­tion, remove the breather hose from the reser­voir and plug one end with your thumb. Air should not escape when you blow air in from the unplugged end. 

If air escapes or you find a tear you will need to replace the breather hose.

#4: Poor Mask Seal

  1. Make sure the mask is sealed prop­er­ly- suck test. Put the mask on your face and inhale while block­ing the upper air inlet port. This should cause the mask to draw to your face.
  2. Use a mir­ror to make sure the mask valves are open­ing and clos­ing cor­rect­ly when the mask is on. 
  3. Make sure to not touch the sil­i­cone valve flaps when putting on the breather hose. 

#5: Pulse Oximeter Issues 

  1. Make sure the bat­ter­ies are not low. 
  2. Make sure the user does not have any type of fin­ger­nail polish. 
  3. Make sure they are not grasp­ing the han­dle­bars too tightly 
  4. Change fin­gers if the read­ing is slow to respond. 
  5. Make sure they don’t have exces­sive move­ment of the finger.

See Also: Trou­bleshoot Your Pulse Oximeter

#6: Failed Air Separator (LiveO2 AC)

Each air sep­a­ra­tor has an inter­nal tester to assures air is sep­a­rat­ed into oxy­gen rich, +O2, over 75% and oxy­gen reduced, ‑O2 mix­tures, below 16%.

This is the amber light tester assures that oxy­gen is at least 75% pure. At a 10 LPM flow rate, it also assures that the ‑O2 lev­el is less than 16%. 

Amber light is off — the sys­tem is work­ing properly.

This test allows LiveO2 users to know their sys­tem is always work­ing with­out need for repeat­ed test­ing. We test all air sep­a­ra­tors before ship­ping, but they can fail over time, and some­times dur­ing transport. 

When an air sep­a­ra­tor fails, the amber light glows like in the image below. If you see this then go to the amber light diagnostic.

#7: Failed Valve

This one is very rare. Every sys­tem is pres­sure test­ed before shipping.

Switch­es between +O2 and ‑O2 should cause a dis­tinct and audi­ble latch as the valve locks into the oppo­site posi­tion. This latch mech­a­nism assures three things:

  1. The mechan­i­cal com­po­nents of the valve are work­ing prop­er­ly each time the user switches;
  2. The valve ful­ly switched between ‑O2 and +O2 air to dis­al­low mix­ing inside the valve;
  3. The valve is inter­nal­ly sealed.
Demon­stra­tion of Prop­er func­tion­ing valve with latch effect 

If you there is no dis­tinct latch. Please con­tact cus­tomer ser­vice.

#8: Internal Reservoir Leak

If you are still hav­ing prob­lems dis­con­nect the breather hose and insert it into the over­flow release port

This iso­lates the air sup­ply to only ‑O2 bypass­ing the oxy­gen reser­voir and valve.   Exer­cise breath­ing this air.   If you desat­u­rate with this con­fig­u­ra­tion dif­fer­ent­ly than on the ‑O2 set­ting please con­tact cus­tomer ser­vice.

See Also:

All else fails Order a Tester

Con­tact sup­port and we can pro­vide a sep­a­rate oxy­gen tester that will enable you to test the actu­al out­put of oxy­gen from the reser­voir at the mask.

We put this last because every air sep­a­ra­tor has a built-in tester that con­tin­u­ous­ly tests the oxy­gen lev­el cre­at­ed by the air sep­a­ra­tor. This built-in tester con­tin­u­ous­ly assures prop­er oxy­gen concentration.

Our sup­port depart­ment can option­al­ly pro­vide an oxy­gen tester to con­firm the lev­els are cor­rect as deliv­ered to the mask. Oxy­gen Test Meter Deposit

Relat­ed articles:

Updated on May 18, 2022

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