How many liters of O2 is really safe with COPD?

  1. Hi this is my first time posting I tried to search my question but the search was not working. I'm a newly licensed RN and I'm not working yet so I'm a little unsure of my knowledge. Ok so some background before my question. My husbands great grandma was recently hospitalized for SOB. When we went so see her I noticed she was on 15 liters of O2 I thought wow that's a lot later I found out that she has COPD. Imediatly I thought that's too much oxygen for someone with COPD. I questioned the nurse and RT together they both said that's what she needs. So the next day they move her to hospice for the reason that she cannot get rid of the CO2 and I'm thinking no wonder with the O2 so high. Now in hospice she is still on 15 liters and going down hill quickly. Just 6 months ago I was taught with COPD 2-3 liters max. So my question is am I way off base are the hospitals doing something different now?
  2. 27 Comments

  3. by   Okami_CCRN
    COPD patients are usually given 1-2 liters of Oxygen on nasal cannula. I think you may not have all the pieces of the story, people are not moved to hospice just because their CO2 isn't coming down.
  4. by   Snowbaby87
    The doctors told the family that she is retaining carbon dioxide her fingers and toes are turning blue and black and eventually she would go into a coma and not wake up.
  5. by   Snowbaby87
    I think hospice was more of the daughters decision because the doctor told her that he did not think her mom would make it and they could keep her comfortable.
  6. by   rn/writer
    We can't give you any advice on your personal situation--it's against our Terms of Service. But we can explain some of the principles at work with COPD patients.

    Many COPDers do well with 2-3 liters. But the rule is to give them what they need to stay alive. If 2-3 L isn't enough to keep their O2 sats at a reasonable level (normal could be 85% with COPD), then they get more O2. Raising the O2 level could very well knock out their respiratory drive, but staff then needs to be ready to bag the patient or otherwise provide respiratory support.

    If someone with COPD is coming to the end of their life, they may well need a higher level of O2. They aren't denied this just because they have COPD.

    I'm sorry your family is going through this.
  7. by   Snowbaby87
    Thanks I was just really confused because that was just going against everything we were taught and since I'm not working yet I don't have any personal experience to draw from.
  8. by   rn/writer
    Quote from Mardisb
    Thanks I was just really confused because that was just going against everything we were taught and since I'm not working yet I don't have any personal experience to draw from.
    In my tagline I have a quote that applies here:

    Education teaches the rules. Experience teaches the exceptions.

    It's sad when you watch someone you care about going downhill. If you want to understand their rationale, ask them to explain it to you. As long as you aren't confrontational or acting like you want them to justify their decision to you, they should be able to help you.

    As a previous poster mentioned, patients aren't placed in hospice unless there is more going on than just retaining CO2. That can be fixed by dialing down the O2. If they aren't decreasing the level, it would appear that they are taking into account other things that are going on and treating the retention of CO2 as an unwelcome but unavoidable side effect.

    Please, ask someone involved in her care for more information--not because you disagree, but because you want to understand.
  9. by   StrwbryblndRN
    I have noticed that not everyone is on the same page in regards to COPD and O2.
    I have had 2 different rapid responses with COPDer's. First one I put a non rebreather on him. Sats came up. At the time I did not put two and two togerther (new grad). The MD got mad.
    Speed up two years later and the same thing happened. This time I did not put a nonrebreather on him and RT therapist questioned why then proceeded to do so.
    IMO, not one action is recommended for everyone.
  10. by   Esme12
    i am sorry your family is going through this. . i agree with rnwriter.....oxygen must be delivered(not denied) to these patients carefully due to the complications that arise in their care. in many stages o2 will be administered to counter hypoxemia and to give comfort in late stages of the dsease.

    there are techincally two types of "typilcal copd. the "blue bloaters" and the "pink puffers". not all copd patients are sensitive co2 retainers. o2 will be given to counter act hypoxemia as the hypoxemia becomes life threatening. the problem is that many people trat the numbers and not the patient....a copd patient may happily live with an o2 sat of 83% that you and i would be cyanotic and gasping.

    a "pink puffer" is a person in which emphysema is the primary underlying respiratory problem. emphysema is caused by the destruction of the airways distal to the bronchiole. it involves the gradual destruction of the pulmonary capillary bed the decreased inability to oxygenate the blood. the body then has to compensate with a lower cardiac output and hyperventilation. eventually, because of the low cardiac output, people afflicted with this disease develop muscle wasting and weight loss. they develop a reddish complexion and a "puffing" appearance when breathing hence "pink puffer".

    out of the two types "pink puffer" or "blue bloater", a "pink puffer" has a better overall prognosis if treatment is sought early. thesesa re the big co2 retainers and o2 administration needs to be watched closely as the breathe on a co2 drive not an o2 drive. so if the o2 levels rise the respiratory drive shuts down.

    a "blue bloater" is a person that actually suffers from chronic bronchitis. utilmately called cor pulmonale due to the heart failure caused by the chroic obstruction of the lungs preventing the circulation of blood on it's way to getting o2 from the lungs. chronic bronchitis is caused by excessive mucus production with airway obstruction and notable hyperplasia of mucus-producing glands. unlike emphysema, the pulmonary capillary bed is undamaged. instead, the body responds to the increased obstruction by decreasing ventilation and increasing cardiac output. this is a horrible mismatch within the body that results in a rapid circulation in a poorly ventilated lung leading to hypoxemia and polycythemia. with this occurring, as well as increased carbon dioxide retention, these people have signs of heart failure and are labeled as "blue bloaters". the prognosis for a "blue bloater" is very poor.

  11. by   leslie :-D
    keep in mind, hospice pts will require o2 according to their comfort levels.
    and that is how we guide our care...not according to med'l indications, but comfort ones.
    they're (hospice) is doing what they need to do, for your grandma's sake.

    wishing you peace and comfort.

  12. by   Iowa RN2006
    Since your husband grandma is hospice they will treat the COPD different than if she were not end of life care.
    If she were not end of life. I have always been taught that you first treat the low 02 sat then deal with treating the high C02 for example you have a COPD pt that 02 sat is in the 70's you put them on higher levels of 02 to get the sat up to a reasonable level and then begin to titrate the 02 back down and if need be the patient can be placed on a bipap to help blow off some of that C02. (i have always been bad with blood gases, infact just posted a thread trying to understand them better.) so I could be wrong but if you dont treat the low 02 sat the pt will go into ARDS and then you will have more problems. I am also not saying to ignore the fact the the pt is a retainer but keep them oxygenated is your first priority.
    Since your family member is hsopice and end of life care they will not treat the C02 retention. This could be one reason she is "going down hill" quickly. if she retains alot of c02 she will eventually go into coma and her need to breathe will decrease until she eventually stops breathing. it is actually a very peacful way to go because you are just very tired and sleepy.
    I am sorry you and your family are going through this.
    Last edit by Iowa RN2006 on Nov 22, '11
  13. by   nurseprnRN
    the short answer is in the physiology of acid-base, because it's less an oxygen question than a ventilation question. briefly, you and i breathe more deeply when we exercise not because we need more oxygen (there's no way to increase your blood oxygen by breathing more room air), but because we need to get rid of co2 , the extra we are making when we carry something up the stairs or run. that you can blow off the more you hyperventilate.

    the way our respiratory center decides whether to do that or not is based on the blood ph it sees circulating by. co2 works like an acid, lowering the blood ph; lower ph (from whatever reason..we'll get back to that) says, "hey! more deep breathing needed here! get rid of this co2 and get the ph back to normal!"
    this is important: the normal respiratory driver is not hypoxia (low oxygen), but hypercarbia (high co2). your (normal) lungs' first job is to manage co2 levels, not to manage oxygen. that comes second. really. remember that.

    now, when lungs fail, their ability to manage co2 decreases. co2 rises in the blood, and eventually that little sensor wears out and stops working. fortunately, there's a back-up system, which is an oxygen sensor. in chronic co2 retainers, their respiratory drive is not elevated co2 levels, it's falling oxygen levels. so, if their ventilation is inadequate, the body doesn't kick in with an elevated respiratory rate and minute volume (that's the total volume of air moved in and out in one minute) until the blood oxygen drops below threshold.

    what this means is that someone who is a chronic co2 retainer is always a bit on the acidotic side (see below). it also means that if you give him oxygen to raise his spo2, his body will say, "ahh, no need to breathe now, all is well" until he stops long enough to drop his o2 back to make-me-breathe levels. the problem is that some people will stop breathing long enough to raise their co2 to lethal levels before the oxygen level gets low enough to make them breathe again, and they die. thus "never give a chronic lunger (well, at least a chronic co2 retainer, the blue bloater) a lot of oxygen, it's bad for them." now you know why.

    here's a tutorial i used to teach acid-base (which is really most of abgs) and your question is probably answered here. if not please come back and ask me.
    you want simple abgs? piece o' cake. people who have seen this before, well, just scroll on by. newbies who want a brief abg's refresher, take out your pencils and a piece of paper, cuz you'll need to do a bit of drawing <g>.

    i taught abg interpretation for yrs in a way that made it pretty foolproof. you will make your own key to interpret abg's, and will be able to reproduce it from memory any time you need to with very little trouble if you learn a very few **key concepts**, labeled **thus**..

    take a piece of paper. make a big box on it, then draw vertical and horizontal lines on it so you have four boxes. i will try to make this come out, should have


    where the four boxes a,b,c,d are such that a is above c and b is above d. you don't need to label the boxes a,b,c,d, just get them in the right alignment. (this is way easier with a whiteboard :d bear with me).

    *inside* each of the 4 boxes write the following, down their left edges:

    now, outside the big box do the following: above the "a" box write "resp"; above the "b" box write "metabolic"

    to the left of the "a" box write "acidosis" and to the left of the "c" box write "alkalosis"

    now you have a "resp" column and a "metabolic" column, an "acidosis" row and an "alkalosis" row. so you have respiratory acidosis and alkalosis boxes, metabolic acidosis and alkalosis boxes.

    with me so far?

    now, you're going to label the primary derangements, so later you can tell what's the derangement and what's the compensation. ok? in the respiratory column, underline co2s. in the metabolic column, underline the bicarbs. that's because in **respiratory disorders, the co2 gets messed up**, and in **metabolic disorders, the bicarb is messed up**. you knew that, or could figure it out pretty quick if you thought about it, right? thought so.

    now. you are going to put upward-pointing and downward-pointing arrows next to the ph, co2, and bicarb labels inside every box. ready?

    ph first. in the "alkalosis" row, make up arrows next to ph, because **ph is elevated in alkalosis (by definition)**. put down arrows in the acidosis row's phs, because **acidosis means a lower that nl ph**.

    remember that **co2 is acid** and **bicarb is alkaline** (this is the end of the key concepts. not too bad, huh?). (oops, i forgot: **nls are generally accepted as ph 7.35-7.45, co2 35-45 (nice symmetry there), bic 19-26**)

    now go to the box that is in the respiratory column and the acidosis row. figured out that co2 must be elevated, because it's a respiratory problem with low ph? good. put an up arrow next to that co2. go to the respiratory alkalosis box. figures that co2 must be low to cause this, right? put a down arrow next to that co2.

    ok, now go to the next column, the metabolic one. i think you can figure out what happens here: in the metabolic alkalosis box, put an up arrow next to the bic, because high bicarb makes for metabolic alkalosis. put a down arrow next to the bic in the metabolic acidosis box, because in metabolic acidosis the bicarb is consumed by the acids and is low.

    you are now going to put arrows next to the blank spots in your boxes that show compensatory movements. ready? ok, what does your body want to do if it has too much acid? right, retain base. yes, of course if your body has too much acid it would like to get rid of it...but if it can't do that, then retaining bicarb is the compensation. so for every elevated co2 you see, put an up arrow with its bicarb. (chronic co2 retainers always have elevated bicarbs, and this is why. and it takes at least 24h for this to occur, so you can tell if a high co2 is acute or chronic that way) you will find an up arrow next to the co2 in the resp/acidosis box.

    so if your body is short on acids, what does it do? right, excrete base. so put a down arrow next to the bicarb in the resp/alkalosis box, because chronic low co2 makes the body want to get back into balance by getting rid of bicarb.

    likewise in the metabolic/alkalosis box, a high bicarb makes your body want to retain acid, increasing co2 being the fastest cuz all you have to do is hypoventilate, to bring your ph back towards normal. put an up arrow next to the co2 in the met/alk box. see the pattern here? put a down arrow next to the co2 in the met/acidosis box, because if your body has too much acid in it (think : asa overdose? dk**a**? lactic acidosis from ischemic bowel?) it will want to get rid of co2 to compensate, and the fastest way to do that is to hyperventilate.

    ok, i hear you wailing: but how do i know whether that elevated or decreased co2 or bicarb in my abg report is primary or compensatory?

    well, now you have your key. so take your abg reports and look at them. say, try these. (notice that o2 levels have nothing to do with acid-base balance abg interpretation) (ok, if you are very hypoxic you can get acidotic...but you see that in the metabolic component, not the o2 measurement, because it's lactic acid your body is making if it's working in an anaerobic way)

    1) ph = 7.20, co2 = 60, bic = 40.

    first thing to look at is the ph. 1) is acidosis, with a low ph. look at your acidosis choices (you have two). find the acidosis where both co2 and bicarb are elevated, and you find your answer: respiratory acidosis with metabolic compensation. this is what you see in chronic lungers who have had high co2's for so long their kidneys have adapted to things by retaining bicarb. (it takes at least 24 hrs for your kidneys to make this compensatory effort, so you can tell if your resp acidosis is acute (no or little change in bicarb) or chronic)). (remember, your lungs' first and most important job is not getting oxygen in, it's getting co2 out, and when chronic lungers have co2 retention, they're really getting bad. people with acute bad lungs will often have low oxygens and low co2's , because their ability to gain o2 goes first, and while they're trying to deep breathe their way back to a decent pao2, they hyperventilate away their co2. we see this in big pulmonary emboli and pneumocystis pneumonia and others ....but i digress....)

    2) ph = 7.54, co2 = 60, bic = 40
    ph here? this is alkalosis, with a high ph.
    the only box where ph is high and co2 & bic are both elevated is metabolic alkalosis with respiratory compensation. sometimes you'll see this in people who have a big-time antacid habit. really. (you can get a short-term metabolic alkalosis with rapid severe vomiting, because the body's normal balance between acid and base has been disrupted due to a sudden loss of acid. things will equilibrate pretty quickly, though, all things considered.)

    so even though you have identical co2's and bicarbs, you can look in your boxes, find the match, and see what you have. remember you underlined the primary disorder in each box?

    wanna try another one?

    3) ph = 7.19, co2 = 24, bic = 12. bingo, you found it: an acidosis where the co2 and the bic are both low. only fits in the metabolic acidosis box, so you have a metabolic acidosis with a respiratory compensation effort. incidentally, this is what you see in diabetic ketoacidosis, when they come in huffing and puffing to blow out that co2 because their ketosis is so high. also you see this picture in asa od's, because this is acetylsalicylic acid they ate, and the fastest way to get rid of acid is to blow it off via hyperventilation. increasing your bicarb takes 24-48 hrs. another quick way to get a metabolic acidosis is to poop out a lot of diarrhea, because you lose a lot of bicarb that way. another classic place for this is in mesenteric artery thrombosis, in which you have a lot of ischemic bowel sitting in there screaming for oxygen and making lactic acid when it can't have any.

    i know this is long, but trust me, you'll never go wrong with it, and you can recreate it anytime. it doesn't really even matter how you set up your boxes, so long as you have a metabolic and a respiratory axis and an acid/alkaline axis. rotate your paper and you'll see what i mean.

    why don't i care about pao2 here? well, because abg's mostly tell you about a/b balance and co2 and bicarb, that's why. probs with them can be serious probs without any abnormality in oxygenation at all.

    remember that pao2 (arterial oxygen, measured in torr or mmhg) is not the same as spo2, (hemoglobin saturation, the percentage of red cells carrying oxygen). if you think they are, your pt could be in serious trouble before you do anything. there is a nomogram that shows you the relationship between arterial oxygen and saturation, which i regret i cannot reproduce here. but you can sketch out a basic version...

    draw a graph where sats are on the vertical (left) axis and pao2's are on the horizontal (bottom) axis. draw little shaded band across the top at the 95%-100% sat areas. that's your normal saturation. draw a few dots there indicating a line of pao2's of 80-100, because those are normal pao2's.

    now draw a dot for spo2 of 90 and pao2 of about 75. now, another dot showing spo2 of 85 and pao2 of about 60. another dot: spo2 of about 80 and pao2 of about 55. connecting all these dots should give you a sort of s curve, indicating that while the top is pretty flat in the pao2 80-100, spo2 95-100 range, pao2 drops off like a shot at decreasing spo2 levels.

    your pt with a sat of 85 is not doing ok, he's in big trouble. while a pao2 of 75 torr isn't too bad at all, a sat of 75% is heading for the undertaker unless dealt with.

    here's my very favorite abg of all time: ph = 7.11, pao2 = 136, paco2 = 96, bicarb = 36.
    what happened to this lady? what will happen next?
    "call" if you have any questions...
  14. by   rn/writer
    Fantastic, GrnTea, just fantastic. Thank you!