Syncope With the Enema Tip In Place
A 58-year-old man arrives in radiology for a single-contrast barium enema. He takes metoprolol for hypertension, took his morning dose, and has been NPO since midnight. Ten minutes into the study, with the enema tip in place and the bag 90 cm above the table, he says he feels "hot and queasy." He is pale and drenched in sweat. Radial pulse is 48 bpm and thready, respirations 22/min and shallow, blood pressure 86/52 mmHg. There is no wheeze, no urticaria, no angioedema, and no history of contrast allergy. He is alert, frightened, and asks you to "just finish quickly." The radiologist is off-site and the department is otherwise empty.
1. Differentiate the most likely reaction from an anaphylactoid reaction, and state your immediate actions in priority order.
Read the worked answer
Pattern recognition, not recall of a list.
Wet, cold, slow, and nauseated points one way; wheezy, hive-covered, and fast points the other.
- Favors vasovagal: diaphoresis with bradycardia (48), hypotension, nausea, pallor, no urticaria, no wheeze or stridor, no prior contrast reaction.
- Favors anaphylactoid: urticaria, angioedema, bronchospasm, tachycardia, hypotension that does not respond to supine positioning.
Two features of this patient make a vasovagal response both more likely and more dangerous: he is volume-depleted (NPO since midnight) and he is beta-blocked (metoprolol blunts the compensatory tachycardia you would normally use as an early warning sign, and can deepen the bradycardia).
Actions, in order:
- Stop the flow and clamp the tubing; lower the bag.
- Remove the tip only if it can be done without delay or injury; otherwise leave it in place.
- Lay him supine and elevate the legs 20–30 degrees.
- Loosen clothing, cool cloth, check a glucose if protocol allows.
- Vitals every 5 minutes; oxygen if SpO2 falls below the ordered threshold.
- Call for help and notify the radiologist; be ready for a fluid bolus per protocol.
- Do not leave him alone.
The trend matters more than the single reading - a falling pulse with a falling pressure is the trajectory toward syncope and seizure.
2. He insists on finishing and the radiologist cannot come. How do you decide whether the study continues?
Read the worked answer
The decision rule is patient safety plus diagnostic value - not the schedule.
Reasons not to resume right now:
- His pressure and pulse have not returned to baseline, and a vasovagal episode can recur or progress while he is on a table with a tip in the rectum and a bag of barium above him.
- A rushed, partial study is usually non-diagnostic anyway, so the study would have to be repeated regardless - the repeat poses more risk than stopping.
- This is an elective diagnostic study. Nothing about the indication is time-critical enough to justify a fall or a syncopal event.
What you may do: reassess in 10–15 minutes. If vitals return to his baseline and he is asymptomatic and consents, call the radiologist for approval to resume with a lower bag height (roughly 60 cm or less) and slower flow. You have the standing authority to stop a study for safety; you do not have authority to restart or alter the radiologist's protocol without contact.
Document the call, the time, and the response - including "no answer."
3. What must be in the documentation of this event?
Read the worked answer
A contemporaneous, objective, timed record. Specifically:
- Vital signs with clock times, including the pre-procedure baseline.
- Objective findings (pulse 48 and thready, BP 86/52, diaphoretic, pale) and the patient's own words in quotes.
- Every action with a time: flow stopped, bag lowered, position changed, oxygen applied, help summoned.
- Who was notified, when, by what route, and what they instructed.
- How much barium was actually instilled and whether the study was terminated or completed.
- Post-event monitoring and the criteria used to determine he was stable for discharge or transfer.
Why this matters: the record is what allows the next clinician to recognize a recurrent pattern, and it is what distinguishes an unavoidable physiologic event from a delay in recognition. "Patient felt faint" is not documentation; a timed set of vitals with the interventions attached is.