100% O2 delivery disadvantages

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Specializes in NICU/L&D, Hospice.

I am a nursing student, going into my final semester (Critical Care). I haven't had experience with ventilators yet. I have looked in my MedSurg book, but there is only one paragraph relating to my question.

A dear, close friend of our family has a 41yo son. He had a massive heart attack 2 days ago and is currently in the ICU on a vent. They are administering 100% oxygen. His prognosis is very, very poor. He had 100% blockage in one of the main arteries. The pulmonary doctor has told my MIL and the mom of the patient that they want to get him off the 100% oxygen ASAP, but even the 100% O2 isn't enough for him. My MIL called me to ask why the concern over the O2 amount. The only thing my book talks about is that anything over 55% for more than 24 to 48 hours could damage the lung tissue. Is this the main issue with high levels of O2, or are there other problems that could come about due to the long term use of a high % of O2 delivery?

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Pulmonary oxygen toxicity is a major concern with high FIO2 levels. In addition, some research seems to indicate that high partial pressures of oxygen can actually cause damage in patients status post cardiac arrest, MI, and CVA. Some people think that increased production of free radicals asociated with high levels of O2 can cause this damage. We will have to wait for more research and perhaps some evidence based medicine to make a concrete conclusion.

I cannot comment on any vent strategies without having a complete history and actually looking at the patients vent settings, labs, and vital signs.

Vent management is very complex. Many times we try to optimize one setting at the expense of another. For example, I increase PEEP to assist with oxygenation and possibly compromise cardiac output. Many people will attempt to optimize Vt's, minute volume, and PEEP when they are looking at increasing oxygenation. In some cases, we actually go outside of establishd guidelines in critical patients. This is where you may hear terms such as; "reverse I:E ratio ventilation and permissive hypercapnea."

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ok woogy, here you go... (i love this site)

http://www.en.wikipedia.org/wiki/Oxygen_toxicity

leslie

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Specializes in CRNA.

100% oxygen denitrogenates the alveoli. Once the nitrogen is gone the alveoli collapse and given enough time, atelectasis results. It can become hard to ventilate those dudes after a few days.

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Specializes in Flight, ER, Transport, ICU/Critical Care.

Ultimately, in the case that you describe - without knowing too much more, I'd suspect that ADRS will be the next clinical outcome regardless. Sad.

Sounds like there are myocardial perfusion issues that will not be solved by ANY amount of oxygen.

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100% FiO2 also offers tons of free radicals to the patient.

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Specializes in NICU/L&D, Hospice.

Everyone has been very helpful. Unfortunately, his is unlikely to live through the evening. His oxygenation has fell even more (47%). Thank you all for the information. I would much rather learn this through a textbook, than real life events. It is truly sad.

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Specializes in surgical, neuro, education.

((((Woogy))) hugs to you, your family, and your young friend.

Cheryl

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Everyone has been very helpful. Unfortunately, his is unlikely to live through the evening. His oxygenation has fell even more (47%). Thank you all for the information. I would much rather learn this through a textbook, than real life events. It is truly sad.

thinking of you and your loved ones.

there's alot of "truly sad" in nsg.

your sensitivity will bring you far.

best of everything.

leslie

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Specializes in NICU/L&D, Hospice.

They took him off the vent yesterday at 5pm, expecting him to die rather quickly. The best thing was the nurse caring for him (3 days) was greatful that they chose that time, so she would be able to be there for him. She was an exceptional nurse.

As things don't go the way we expect, he continued to breathe on his own. It wasn't until 1am that he died. His mother was holding him and he went in peace. Parents shouldn't have to watch their children die, but at least she was able to make peace with him.

Thank you everyone for your kind words. It's times like this that life takes on a new refreshed meaning.

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