Blood Ofygen Level - Minimum to sustain Life?

My father admitted to hospital 1/mo ago..very low blood oxygen level (around 70)..Has per-existing Vascuilitus (Buerger's ??) as well as Hypothyroidism (daily synthetic pill)...diagnosed after bad pneumonia in 2000. Believe he currently has pulmonary hypertension..barrage of tests have been done, incl lung and lymph biopsies, angiogram...no viral/cancer/blockage present... i don't believe that a diagnosis is confirmed, he is being treated for D.I.P. (DESQUAMATIVE INTERSTITIAL PNEUMONIA), as follows: 1.Solumedrol, 2. Epogen, 3. Mycophenolate, 4. 24hr/day oxygen (recently down to level 5/6 from 10), Darvocet & Vicodin for pain from biopsy sugery week ago. We believe that the veins going into the lungs are being affected by inflamation (inflammation), result in less than normal blood exchange out of the lungs.. (heart been working very hard to try keep blood flow rate normal in order to get corrrect amount oxygen thruout sysem-- but was unable to...summized that the veins are constrited, therefore treatment with meds mentioned above). Father curently knows some of the things that drive his blood ox level down (bowel movements,little constipated, waving arms wand, a few other), into the high 60's (he recover's to low 90's within minutes after getting back to bed. What he can't find is " The Required Blood Oxygen Level (minimum)in order to sustain life, w/o 24/7 oxygen mach.(ie..b.o/68 can survive with supplenental treatment.? b.o./75, may be fine,.....but  @ b.o./66, you would die.  What's that "Magic Number" cliff. The goal is 95+, but what does it take to stay alive? TYTY for any assistance

[National Jewish]

Many people can live for extended periods of time with an oxygen saturation of 80-85% but this is very borderline and far less than the ideal of >90%. This should not be the goal.  For this to work, the fall in oxygen level must have been slow to happen, probably over months to years.  An acute lowering of the blood oxygen to <85% is life threatening.

[starion]

The more frequently the O2 level dips below 90% & even lower, the greater complications an individual has--heart, brain, and other organs need high enough O2 levels & will divert the O2 from other areas of the body to get it.

Medicare guidelines (which most US docs & hospitals follow) advise O2 Rx to keep O2 levels at 90+ 24/7.  Not a good idea to see how low a patient can go without O2 24/7--patient can & will sustain permanent damage, particularly with sustained and/or frequent low O2 saturation rates.

Starion

[starion]

By the way, using supplemental O2 24/7 does not mean "the end is near."  Some patients have been receiving supplemental O2 24/7 for 20+ years.

In fact, supplemental O2 is one of the very few treatments that has been shown to prolong life, when used as prescribed.
Starion

[R.Kennedy]

Thank you very much for your speedy response.  I will pass this on to my father. If I understood you correctly, under 90 will start causing and continue to cause damage somewhere (or more) in the body, to some degree. (severity would depend on where damage occurs, the original condition where damage is occurring, and level of owygen in the blood.) Am I close? Thank you again for getting back to me so quickly...just wonderful! Enjoy your week...Sincerely, R.Kennedy

[starion]

By the way, I'm just another patient & NOT a physician or anyone with medical training.  Here's some more info about supplemental O2.

http://www.nationaljewish.org/medfacts/oxygen.html

Aloha,
Starion