The first step in clinical problem solving is making the diagnosis.
There are typically four distinct steps that the family physician undertakes to systematically solve most clinical problems:
1. Making the diagnosis
2. Assessing the severity of the disease
3. Treating based on the stage of the disease
4. Following the patient’s response to the treatment
This is achieved by carefully evaluating the patient, analyzing the information, assessing risk factors, and developing a list of possible diagnoses (the differential). Usually a long list of possible diagnoses can be pared down to a few of the most likely or most serious ones, based on the clinician’s knowledge, experience, and selective testing. For example, a patient who complains of upper abdominal pain and has a history of nonsteroidal anti-inflammatory drug (NSAID) use may have peptic ulcer disease; another patient who has abdominal pain, fatty food intolerance, and abdominal bloating may have cholelithiasis. Yet another individual with a 1-day history of periumbilical pain that now localizes to the right lower quadrant may have acute appendicitis.
The first step in clinical problem solving is making the diagnosis.
After establishing the diagnosis, the next step is to characterize the severity of the disease process; in other words, to describe “how bad” the disease is. This may be as simple as determining whether a patient is “sick” or “not sick.” Is the patient with a urinary tract infection septic or stable for outpatient therapy? In other cases, a more formal staging may be used. For example, cancer staging is used for the strict assessment of extent of malignancy.
The second step in clinical problem solving is to establish the severity or stage of disease. This usually impacts the treatment and/or prognosis.
Many illnesses are characterized by stage or severity because this affects prognosis and treatment. As an example, a formerly healthy young man with pneumonia and no respiratory distress may be treated with oral antibiotics at home. An older person with emphysema and pneumonia would probably be admitted to the hospital for IV antibiotics. A patient with pneumonia and respiratory failure would likely be intubated and admitted to the intensive care unit for further treatment.
The third step in clinical problem solving is tailoring the treatment to fit the severity or “stage” of the disease.
The final step in the approach to disease is to follow the patient’s response to the therapy. Some responses are clinical, such as improvement (or lack of improvement) in a patient’s pain. Other responses may be followed by testing (eg, monitoring the anion gap in a patient with diabetic ketoacidosis). The clinician must be prepared to know what to do if the patient does not respond as expected. Is the next step to treat again, to reassess the diagnosis, or to follow up with another more specific test?
The fourth step in clinical problem solving is to monitor treatment response or efficacy. This may be measured in different ways—symptomatically or based on physical examination or other testing. For the emergency physician, the vital signs, oxygenation, urine output, and mental status are the key parameters.