DDX tools could help to avoid diagnosis errors in the ICU

The idea for the Isabel diagnosis support tool first came to us while sitting in the ICU.  A decade ago, my family and I were spending long hours in the ICU caring for our toddler, Isabel Maude, after she was diagnosed late with necrotising fasciitis. We realized the ICU doctors often can see the long perspective of what happened to a patient, as they see how the patient got there and what mistakes were made along the way. With the luxury of hindsight they can see, for example, that if only a clinician had, metaphorically, turned left instead of right then the patient would not have ended up in ICU.

So, with great interest I read a review of diagnostic errors actually made in the ICU in an article published by by Bradford Winters et al at Johns Hopkins.

http://qualitysafety.bmj.com/content/early/2012/07/20/bmjqs-2012-000803

Do we need more papers telling us how much diagnostic error exists? Hopefully the message is starting to get through. A salient point in this paper is that out of the 31 studies covering 5,863 autopsies, 28% reported at least one misdiagnosis. The authors estimate that as many as 40,500 adult patients annually may die in the ICU with a misdiagnosis. This number of predicted deaths is comparable to those from central line associated bloodstream infections or breast cancer.

The most interesting part, though, was what Winters said in the communications accompanying the paper:

“It may be counterintuitive to think that the patients who are the most closely monitored and frequently tested are more commonly misdiagnosed, but the ICU is a very complex environment,” Winters says. Clinicians face a deluge of information in a distracting environment in which the sickest patients compete for attention, most without being able to communicate with their medical team. “We need to develop better cognitive tools that can take into account the 7,000 or more pieces of information that critical care physicians are bombarded with each day to ensure we’re not ruling out potential diagnoses,” Winters says. 

This point is yet another good argument for using differential diagnosis tools, like Isabel, that are designed to help clinicians make sense of information, rather than just giving them more of it.

~ Jason Maude, Founder of Isabel Healthcare. View the Video of Jason and his daughter Isabel telling their story.

The Isabel Healthcare 1 Minute Read program highlights various diseases and conditions, providing the Isabel tool differential list. Subscribe to the Isabel blog to receive clinical content and articles.

Abdominal Pain Differential Diagnosis

With abdominal pain, it is important to determine what the cause is by taking a good history and the cause of the pain -- like how the pain begins, the location, pattern of the pain, the duration of the pain, and if anything causes or relieves the pain.  The examination of the patient will allow for tenderness to be felt and to identify if any mass exists.  A stomach ache normally refers to abdominal cramps or a dull ache in the abdomen and can be self-limiting and resolve quickly if caused by Gastroenteritis.  Severe abdominal pain indicates pain arising from the abdomen and could originate in the abdominal wall but can also arise from organs contained within the abdominal cavity like the stomach, pancreas or appendix.  Severe abdominal pain is a significant symptom as could require surgical or medical intervention and should be fully investigated. 

Abdominal Pain Causes

Potential causes of abdominal pain including red flagged or "don’t miss" diagnoses which should be ruled in or ruled out quickly, as they could require urgent medical/surgical intervention:

Pancreatitis can present with severe upper abdominal pain radiating to the back, nausea and vomiting.

Peritonitis can occur suddenly with severe abdominal pain, chills and high fever.

Recurrent abdominal pain presents in children with wax and waning abdominal pain, three episodes within a three month period and is severe enough to interfere with a child’s activities.  It is fairly common and difficult to diagnose as not accompanied by easily definable organic pathology but can cause a lot of disruption to the child.

Acute appendicitis should be considered in any child presenting with abdominal pain which starts in the middle of the abdomen and then transfers to the lower right quadrant of the abdomen where the appendix normally lies.  The pain worsens as the appendix becomes more inflamed and other symptoms may be fever and vomiting.  Occasionally constipation or diarrhea may develop.

Urinary tract infection normally present with the urge to urinate frequently, a painful burning sensation when urinating, abdominal pressure or discomfort and sometimes pain in the lower back.

Tests can help determine the actual diagnosis or cause of the abdominal pain by carrying out full blood counts, checking liver and pancreatic enzymes and performing a urinalysis.  Other investigations which may be deemed necessary include an abdominal xray, abdominal ultrasound, MRI, barium xray or CT.

As Isabel is not a rules-based system, it is possible to use Isabel’s natural language processing abilities to obtain a differential diagnosis checklist using other terms like “cramping abdominal pain” which describes the nature of the pain more accurately and potentially narrow the disease list as the symptom is more specific and due to the differential checklist of  abdominal pain spanning many specialities of medicine.

Its also possible to concentrate on a specific part of the abdomen affected like “lower right quadrant abdominal pain” and obtain a differential checklist.

There are many benign causes of abdominal pain but if pain develops suddenly, is severe or is prolonged, then it is important to determine the cause as soon possible and treat accordingly.

~by Mandy Tomlinson, RN, Isabel Quality Assurance Director

About the Isabel Diagnosis Challenge

The New England Journal of Medicine (NEJM) publishes interesting presentations of common diseases and unusual cases in the Clinical pathology Conference (CPC) series. These cases are educational and can pose diagnostic challenges even to the expert physicians at the Massachusetts General Hospital.

Using the clinical features of these cases you can evaluate your own diagnostic skills and compare your diagnostic performance to that of the physicians at MGH. If you are registered with Isabel as a client or have a free-trial subscription, you can use the diagnosis reminder system and run through some scenarios to get a list of likely suspects. Clicking on a diagnosis will take you through to various knowledge sources and links available from within Isabel.

Today's Case

#12:3 N Engl J Med. 366(4):361-372

Demographic: Male, Neonate, North America
Clinical features:

• bilious vomiting
• bloody diarrhea
• fever
• failure to pass meconium
• abdominal distention
• lethargy
• heme-positive stool
• septic shock

STOP !
Before you read further, construct your own: 1) Complete differential diagnosis and 2) Final diagnosis

Differential Diagnoses considered by the MGH panel: Volvulus Necrotising enterocolitis
Final Diagnosis of the case according to NEJM: Hirschsprung’s disease with enterocolitis
Differential Diagnoses of the case as given by the Isabel tool: Volvulus in Gastro, Necrotising enterocolitis in Infectious
Was the final diagnosis given by Isabel: Yes, Hirschsprung’s disease under large bowel obstruction in Gastro