It Takes Failure to Have Respiratory Failure

By Erica Remer, MD, FACEP, CCDS, ACPA-C

I have been performing a lot of chart reviews in my consulting capacity, making clinical validation determinations. Whether I am hired by the payor or the provider, I assess the clinical course and documentation and try to make a fair appraisal. One of the conditions that is particularly irksome is acute hypoxic respiratory failure.

For the newly updated pediatric sepsis definition, a survey of practitioners was undertaken to suss out what the consensus was for the medical condition. A scenario was posed, and the respondents weighed in on whether they thought it constituted sepsis or not. I decided to try that approach with acute hypoxic respiratory failure.

I posted this case on LinkedIn:

O2 sat of 89 percent on room air. 2L by n/c gets pulse ox to 95 percent. PE: No acute distress. Not toxic appearing. Exacerbation of COPD.

Do you think this is acute hypoxic respiratory failure?

Almost all of those who responded gave me a resounding “no.” A couple of people wanted a little more information, to try to determine if the patient had chronic respiratory failure. One person cited Pinson & Tang’s position that a pO2 < 60 mmHg (SpO2 < 91 percent) on room air was sufficient to conclude hypoxemic respiratory failure.

This highlighted the fact that in clinical documentation integrity (CDI) practice, we often depend on dogma put forth by respected individuals in the field (including me!) We teach our providers and create internal clinical guidelines to support our positions. If there is established evidence-based literature, great! If not, we sometimes fall back on expert opinion. One of the pitfalls of this is we sometimes spurn common sense and rely too heavily on medicine by checkbox.

I believe I have sorted out why this condition unsettles me and causes us all such grief. I am going to try to lay it out for you all, clinicians, coders, and payers. Please note that I am specifically honing in on adult respiratory failure.

The ICD-10-CM code J96.01 is titled “Acute respiratory failure with hypoxia.” Why is it written that way, and not “acute hypoxic respiratory failure?” Let’s deconstruct this.

I posit that first, you need to determine if there is acute respiratory failure.

Acute respiratory failure implies a rapidly developing, severe, and life-threatening impairment of the body to intake or absorb adequate oxygen – or to expel sufficient carbon dioxide. If left untreated, the individual is at high risk of dying from inadequate oxygenation of tissues (e.g., heart or brain) or profound acidosis, which is incompatible with life.

Chronic respiratory failure is more insidious. It often develops more gradually, so the body has time to compensate. The patient learns to deal with shortness of breath if they walk too fast or to stop exerting themselves before ischemia gives them chest pains. If the person comes to equilibrium in chronic respiratory failure, they will have a chronically reduced oxygen level, persistently elevated carbon dioxide level, or both, but their pH will be near-normal. Their status is tenuous, and a new stressor can disrupt the delicate equilibrium, setting off the same life-threatening cascade of events as acute respiratory failure. This is termed acute and (or on) chronic respiratory failure.

The second part of the title is “with hypoxia.” Having a pO2 of < 60 mmHg constitutes hypoxemia, a reduced oxygen level in the bloodstream. Hypoxia is defined by Merriam-Webster as “a deficiency of oxygen reaching the tissues of the body whether due to environmental deficiency or impaired respiratory and circulatory organs.” Hypoxia is the life threat, although it often follows and is heralded by hypoxemia. This is why the code isn’t “with hypoxemia.” Practically speaking, however, we use the terms interchangeably.

In order to have acute hypoxic respiratory failure, you need to have all components: acuity, low oxygen delivery to tissues, and the threat to life.

People are (mis)interpreting Pinson and Tang’s guidance to mean that simply having a pO2 < 60 (SpO2 < 91 percent) or a P/F ratio of less than 300 is adequate to diagnose acute respiratory failure with hypoxia. Even with the caveat that one cannot apply the criteria to patients with chronic respiratory failure, this is not sufficient. This level of oxygen establishes hypoxemia, but more is needed to satisfy the acute respiratory failure piece.

Acute respiratory failure is symptomatic and requires substantial treatment. The symptoms/signs may be pulmonary in nature, like shortness of breath, tachypnea, or intercostal retractions. They may relate to the consequences of the hypoxia or hypercapnia, like anxiety, lethargy, or confusion. These patients typically appear acutely ill.

Treatment is necessary. When I practiced clinically, there were patients on whom I would toss a nasal cannula at a couple of liters per minute. I was trying to make them more comfortable, but I didn’t necessarily think they would succumb without it. Patients in acute respiratory failure need treatment to survive.

For hypoxia, they need significant oxygen supplementation. Most pundits expect to see four or more liters per minute (whatever you consider “high-flow”). A patient does not need to be intubated, but if they are intubated to address air exchange defects (as opposed to “airway protection”), they are in respiratory failure.

Let us remember that when we are reviewing records, we are not assessing the patient directly, but the documentation. It makes it so much easier if the provider produces good documentation to arrive at a valid conclusion. Here are the things I look for:

• A history describing development over a short period of time;

• Signs or symptoms of respiratory distress (e.g., shortness of breath, tachypnea or bradypnea, air hunger, supraclavicular/intercostal/subcostal retractions, accessory muscle use, abnormal vital signs and/or findings on lung exam) or end-organ dysfunction from hypoxia/hypercapnia (e.g., restlessness, anxiety, reduced level of consciousness, metabolic encephalopathy, diaphoresis, dysrhythmias);

• Consistency in documentation;

  • The history of present illness depicting a patient in distress with symptoms consistent with etiology. Description of baseline status if pertinent;

  • A general description including some degree of distress, ill-appearing, or in extremis (e.g., “in no acute distress, non-toxic, not ill-appearing” would be inconsistent);

  • Re-evaluation of the patient’s condition at reasonable intervals;

  • The declaration of an impression of acute hypoxic respiratory failure at the time (e.g., not days later for the first time, when the patient is no longer exhibiting the signs and symptoms). I expect it to be high on the impression list, not number 9 as an afterthought;

  • If the diagnosis is prompted by a query, it better be supported with the thought process by the provider. I don’t want to see a random diagnosis just pop up without clinical support and only appear once;

  • The diagnosis carried throughout the record by all providers. When the condition resolves, it should be resolved in the impression list. It can even be removed if the length of stay is prolonged, but it should reappear in the discharge summary; and

  • No unresolved conflicting documentation amongst clinicians.

• Critical care time being claimed in the ED, the drawing of an arterial blood gas, a pulmonary consult, and/or admission to the ICU are supportive (but not necessary) clinical indicators; and

• Treatment suggesting the diagnosis is clinically valid and significant

  • E.g., high-flow oxygen, CPAP, BiPAP, intubation; and

  • Aggressive treatment of causative conditions (e.g., antibiotics, pulmonary toilet, steroids, respiratory treatments as indicated).

How about that case? The patient meets criteria for hypoxemia, but is in no acute distress, nor is toxic-appearing. They have a reasonable etiology (COPD), but they only need 2 L/min by nasal cannula. These clinical indicators do not seem to support acute or acute-on-chronic respiratory failure with hypoxia. I would diagnose this as “acute exacerbation of COPD with hypoxemia.” If I were the documenter, I would also have discussed the patient’s baseline to support chronic respiratory failure, if I felt they had it.

Clinicians, if a patient has a life-threatening respiratory issue, think acute or acute-on-chronic respiratory failure. Document the historical and physical points and data that support the diagnosis. Specify whether it is hypoxic, hypercapnic, or both. Be precise and consistent in your documentation. Don’t downplay it or attribute the signs and symptoms solely to alternate diagnoses.

I would recommend linking the acute or A/C respiratory failure to the underlying etiology. I also like linking the manifestations. Detail your thought process and make it hard for the payor to deny the existence of the condition:

Acute-on-chronic hypoxic respiratory failure from pneumonia complicating acute exacerbation of COPD, with pO2 86 percent on baseline home O2 2 L demonstrating air hunger, accessory muscle use, and diffuse wheezing.

If the patient has a low oxygen level, but is not exhibiting signs of respiratory failure, and only requires low-flow oxygen supplementation, call it hypoxia or hypoxemia. If they have acuity, and severity, and require sufficient treatment, call it acute respiratory failure with hypoxia.

Payers do not misinterpret this article and cite that the documentation has to have all of the elements above, or else acute respiratory failure is ruled out. There is always an underlying condition, but there are very few diagnoses in which acute respiratory failure is considered inherent (e.g., acute respiratory distress syndrome, ARDS). Don’t try to gaslight the provider that acute respiratory failure is inherent to pneumonia or heart failure. Clinicians must take in all the facts and data and use their clinical judgment to render a diagnosis.

If you are going to take anything from this article out of context, don’t use it at all!

Physician advisors, bookmark this article and send it to your providers when you discover opportunity in your medical staff’s documentation of respiratory failure. Feel free to condense it and make a tip sheet for them.

Finally, CDI specialists, don’t try to force the provider to use the diagnosis of acute respiratory failure because it is a major comorbid condition or complication (MCC). Our job is to make sure the medical record is accurately depicting how sick and complex the patient is. They need to look as sick in the EHR as they do in real life: no less, but no more.

(For more education on optimal documentation practices, check out Dr. Remer’s Documentation Modules with CME).

Reference: Richard Pinson, Cynthia Tang, Acute Respiratory Failure – All There Is To Know, Pinson & Tang, September 5, 2023.