Monday, March 08, 2010

"Illness"

I had an intersesting patient this week. JM (we'll call him) is a 43 yo male truck driver with history of asthma, depression, and alcohol abuse who was admitted from clinic after a pulse oximeter (hand held device that measures O2 in the blood) read his oxygen saturation as 78% (normal is 98-100%). At home he has been prescribed multiple inhaled bronchodilators, inhaled steroids, theophylline, and 5 L of 02 via nasal cannula. He was taken from an oustide clinic to the ED, treated with albuterol inhalers, his pulse ox checked again, and it was decided that he should be admitted. His past medical history is significant for numerous admissions for asthma exacerbations, but under names with different demographic information (eg birthday).

The story gets interesting when the pt is admitted to the unit, a blood gas is done which showed a respiratory alkalosis. This means his blood was basic (high pH) with respect to the physiologic norm. Asthmatic patients in crisis are generally unable to sufficiently expel all of the accumulating CO2 due to their constricted airways, and treatment is aimed at opening those airways so that efficient ventilation and thus gas exchange can take place. In the absence of good ventilation, CO2 builds up in the lungs and makes the blood acidic. This patient had the opposite problem, however, which called into question the diagnosis of acute exacerbation of the asthma, which would typically present with an acidosis, rather than an alkalosis.

A respiratory alkalosis can be seen in the case of hyperventilation. When the respiratory rate increases, more CO2 is blown off, decreasing the amount of CO2 in the blood, thus increasing the pH (rendering the blood alkalotic or basic). Why would the respiratory rate increase? In the case of an acute, pure respiratory alkalosis, panic attack is high on the list of possible causes.

The patient was dishcarged to be cared for by us on the floor team after a brief stay in the unit. We checked his blood levels for some of his home medications which showed that he had not been taking them at all. While staying on the floor, the patient rested comfortably, but when visited would complain of chest tightness and would have very poor respiratory effort, shallow breaths, and appear to be in moderate distress. At night and during the day, the patient could be seen to be napping or sleeping comfortably without any evidence of shortness of breath, difficulty breathing, or increased respiratory effort.

The clinical picture I have painted you led us to suspect that his current condition was not an acute exacerbation of asthma. The tricky thing about taking care of patients such as this is parsing out how much of their illness is organic (i.e. deriving from diseased lungs), and how much is psychogenic, i.e. what components of his symptoms were derived from his mind. Despite being psychogenic, the symptoms the patient complained of and the signs he demonstrated on exam are nevertheless real, just not fully explainable by an organic process localized solely to the respiratory tract and consistent with a diagnosis of asthma.

The real challenge is also trying to differentiate whether the pt is conciously faking, i.e. malingering, in order to get some secondary gain i.e. time off work, disability, drugs, or something else, or whether the psychic gain is unconcious. In patients with conversion disorders, a psychic stressor manifests itself through physical symptoms. It is possible, then, that our patient has some stressor in his life that is so profound that his body manifests physically what the mind is feeling psychically. Alternatively, our patient is faking his symptoms or exaggerating them in order to recieve care and to be placed in the dependant role of "patient". What makes this kind of patient especially trying is that it is very tempting to disregard all of their complaints as being psychogenic, when of course they may actually be genuinely sick. It's the old problem of crying wolf. In Aesop's fable, the villager's eventually turned their back on the boy who was eaten by the wolf in the end. The same thing can happen to patients with factitious disorders who every now and again will be genuinely sick, but have cried wolf so frequently that they are disregarded. Trying to sincerely engage a patient in whom you are questioning the legitimacy of their symptoms is very challenging. Those who have cared for a factitious patient will know what I mean, those who haven't may think I am callous for even entertaining the possibility of considering that a patient may be feigning illness. What do you do when this patient comes back to the ER short of breath?


*Editor's note: the patient presented is a composite and the information presented does not reflect the clinical course of any one person for whom I have cared. JM is a pseudonym.

2 comments:

Maggie said...

What a hard question to answer! What is your answer to that question. You admit them don't you, even though that would be a waste of time and resources. It would be hard to turn your back when you can clearly see something's happening to your patient.

Dan's mom said...

HIPPA will be much happier with this composite patient. I'm glad you've reached a rotation that is a better fit for you. There are many medical fields that call for such different approaches, I knew there would be one where you felt more confident & comfortable. Psychogenic disease is hard since the symptoms are real but the causitive agents are not pathogens or disease processes. Dan's now on psych - Mr. Composite might be more his ballywick right now. I'm sure it's not going to be his field either but he does have real-life experience since his brother has had some "issues" anecdotally since <3.