Emergency Medicine

CHEST PAIN

General Medical Emergencies 57

6 Send blood for D-dimer only when the pre-test probability is low.
(i) Discharge the patient if this D-dimer is negative, that is no DVT,
provided alternative diagnoses do not require further care.

7 Perform Doppler ultrasound on all moderate and high pre-test probability
patients, and when the D-dimer test is positive.

MANAGEMENT

1 Give the patient analgesia such as paracetamol 500 mg with codeine 8 mg
two tablets orally q.d.s. or an anti-inf lammatory such as ibuprofen
200 –400 mg ora lly t.d.s. or naproxen 250 mg ora lly t.d.s.

2 Commence heparin if the diagnosis is confirmed.
(i) Give LMW heparin such as enoxaparin 1 mg/kg s.c. 12-hourly or
dalteparin according to body weight s.c. 12-hourly.
(ii) Alternatively, give UF heparin 5000 units i.v. bolus followed by
1000–1300 units/h infusion particularly for a large or extensive
DVT, according to local policy.

3 Refer all patients to the medical team if the diagnosis is confirmed.
(i) Some patients may be discharged for outpatient LMW heparin.
Check your local policy.
(ii) Other patients may even be sent home without any treatment at
all if the DVT is confined below the knee
(a) organize a repeat US scan within 5–7 days in those not treated
to exclude more proximal extension of the thrombosis.

4 Get senior ED doctor advice if the diagnosis is still indeterminate.

Aortic dissection

DIAGNOSIS

1 Predisposed to by hypertension typically in males 60–80 years old. Other
risk factors include Marfan’s syndrome, bicuspid aortic valve, coarctation,
cocaine use, iatrogenic trauma or prior cardiovascular surgery.

2 The onset is abrupt with sudden pain that is sharp or tearing, retrosternal,
interscapular or lower in the back or migratory, and may be severe and resist-
ant to opiates.

3 Look for unequal or absent pulses, a difference of blood pressure in the arms,
or the following complications of the dissection:
(i) Aortic incompetence, myocardial ischaemia and haemopericardium
with pericardial rub or cardiac tamponade (see p. 10).
(ii) Dyspnoea, pleural rub or effusion.
(iii) Altered consciousness, syncope, hemiplegia or paraplegia.
(iv) Intestinal ischaemia or bowel infarction with abdominal pain and
bloody diarrhoea.
(v) Oliguria and haematuria.