Abnormal monitor tracing noted on the post-operative ward round

88-year-old woman. Abnormal monitor tracing noted on the post-operative ward round

Eileen Kavanagh is on day 2 after a cemented hemiarthroplasty for a fractured neck of femur. Febrile overnight with a productive cough; antibiotics for a hospital-acquired pneumonia were started four hours ago. Regular medication is amlodipine, atorvastatin and alendronate. No digoxin, no beta blocker.

Stage 1 of 2

The nursing staff ask you to look at the telemetry because the P waves "keep disappearing". Mrs Kavanagh is sitting up, eating breakfast and has no chest pain or dizziness. She is warm and peripherally well perfused. A full 12-lead is recorded at the bedside.

Tracing 1 of 2 for the quiz “Abnormal monitor tracing noted on the post-operative ward round”. — 12-lead recorded at the bedside on the morning ward round. Open this tracing in the studio

Observations

HR: 88
SpO₂ (%): 94
Respiratory rate: 20
Temperature (°C): 38.4
Systolic BP (mmHg): 118
Diastolic BP (mmHg): 64

Bloods

CRP (mg/L): 148
Potassium (mmol/L): 4.1
White cell count (x10^9/L): 14.2

What does this tracing show?

AEctopic atrial tachycardia with 1:1 conduction Your answer
BSinus rhythm with first-degree atrioventricular block Your answer
CAccelerated junctional rhythm with atrioventricular dissociation Correct answer Your answer
DAtrial fibrillation with a regularised ventricular response Your answer
EComplete atrioventricular block with a narrow junctional escape Your answer

Which feature on this paper separates this rhythm from complete atrioventricular block?

AThe PR interval changes from beat to beat Your answer
BThe left ventricular voltage criteria in V5 and aVL show the cause is chronic rather than conduction disease Your answer
CThe atrial rate is slower than the ventricular rate, so no P wave gets a chance to conduct Correct answer Your answer
DThe ventricular rhythm is regular throughout the recording Your answer
EThe QRS complexes are narrow at 92 ms Your answer

Stage 2 of 2

By mid-afternoon she is afebrile at 37.1 °C after paracetamol and the second dose of antibiotics. She remains asymptomatic. A repeat 12-lead is recorded.

Tracing 2 of 2 for the quiz “Abnormal monitor tracing noted on the post-operative ward round”. — Repeat 12-lead the same afternoon. Open this tracing in the studio

Observations

HR: 96
SpO₂ (%): 96
Respiratory rate: 18
Temperature (°C): 37.1
Systolic BP (mmHg): 124
Diastolic BP (mmHg): 68

Taking the two tracings together, what is the appropriate next step?

AGive atropine 500 micrograms intravenously and repeat if the rate falls Your answer
BStart an isoprenaline infusion titrated to a ventricular rate above 60 Your answer
CInsert a temporary transvenous pacing wire today Your answer
DContinue treatment of the pneumonia and monitor on telemetry, with no pacing Correct answer Your answer
ERefer for permanent pacemaker implantation before discharge Your answer

Abnormal monitor tracing noted on the post-operative ward round

The case

On arrival

Observations

Bloods

Observations

Diagnosis

Discussion