Principles of Assessment

History taking

The patient history has 2 components: the history of present illness (HPI) and the past medical history (PMH). If the patient cannot communicate, gather the history from family members, bystanders, and the medications and medical devices found at the scene. Building rapport makes the history better: get down to the patient's level, show empathy, and listen carefully so that you do not re-ask questions the patient has already answered.

Open-ended questions, which cannot be answered with a simple yes or no, are the default because they draw out more detailed information. Closed-ended questions, which can be answered yes or no, are reserved for serious or urgent situations that need fast answers. Diagnosis is not always definitive; sometimes the goal is simply to establish what this patient needs rather than exactly what is wrong.

OPQRST & SAMPLE

Two mnemonics organize the history. OPQRST guides your questions about the present complaint; the table below gives the meaning of each letter with a sample question.

Table 14.1OPQRST & SAMPLE

SAMPLE covers the rest of the patient's history, as the second table shows.

Table 14.2OPQRST & SAMPLE

The medications a patient takes can reveal conditions the patient has not disclosed; a patient who denies diabetes but takes insulin is one example. A good history question tends to yield 2 more good questions.

When taking a history from a child, use simple language, include the parents or caregivers, and remember that children may feel that illness is a "punishment."

Physical examination — 3 techniques

The physical examination uses 3 techniques, which the table below describes.

Table 14.3Physical examination — 3 techniques

When examining an alert infant or small child, reverse the usual order and work from toe to head. Explain each step, examine the child on the parent's lap if possible, never lie about whether something will hurt, and protect the child's modesty.

Body system exams (choose by chief complaint)

Which body system you examine in detail is chosen by the chief complaint.

For a respiratory complaint, always assess first whether breathing is adequate. Then observe the motion of the chest wall, auscultate the lung sounds (wheezes indicate narrowing of the airways; rhonchi and rales indicate fluid), obtain a pulse oximetry reading, and look for edema.

The cardiovascular exam covers the skin color, temperature, and condition, the mental status, the pulse, and the blood pressure (BP), which is taken in both arms because a difference of more than 20 mmHg may indicate an aortic aneurysm. Look for jugular vein distention (JVD) and palpate the chest for tenderness.

The nervous system exam includes a stroke scale, peripheral sensation and movement (unequal findings suggest a possible spinal injury), palpation of the spine, grip and foot strength, the pupils, and the gait.

The endocrine exam looks at the mental status and the skin, since cool, moist skin suggests possible hypoglycemia. Measure the blood glucose, check for an insulin pump, and look for medical identification (ID) jewelry.

In the gastrointestinal exam, observe the patient's position, such as a fetal position or guarding. Inspect the abdomen, auscultate for bowel sounds before you palpate, and then palpate the quadrants, leaving the painful area for last.

For a suspected allergic reaction, the immune system exam inspects the point of contact, the skin for rash or hives, and the face, lips, and mouth for swelling. Listen to the patient's voice and auscultate the lungs for wheezing.

The musculoskeletal exam is mostly trauma-related. Inspect for deformity, swelling, and bruising; palpate gently for crepitation; compare the two sides for symmetry; and palpate from head to toe for multiple injuries.

Critical thinking & decision making

EMTs do diagnose; cardiac arrest is a diagnosis. The diagnoses are often general, however, such as "abdominal pain of unknown cause." A field diagnosis, also called a presumptive or working diagnosis, is based on the history, the physical exam, and the vital signs, and the differential diagnosis is the list of possible conditions that could explain the findings. Compared with traditional medicine or emergency medicine, diagnosis in EMS is urgent, focused, and limited in scope: the goal is to rule out life threats, treat according to protocol, and transport. Red flags are signs or symptoms that suggest a serious underlying condition; tearing abdominal pain that radiates to the back, for example, suggests an abdominal aortic aneurysm (AAA).

Diagnostic heuristics & their pitfalls

Clinicians rely on mental shortcuts, or heuristics, to reach a diagnosis quickly, and each one carries a characteristic pitfall. The table below defines the common heuristics and the error each can produce.

Table 14.4Diagnostic heuristics & their pitfalls

Thinking like an expert means accepting ambiguity as inherent to EMS, knowing the limits of both people and technology, building strong foundational knowledge, learning the conditions that mimic one another, not letting the search for a diagnosis delay needed treatment, and knowing the limits of your own competency.