Focus on the snake & miss the scorpion

47-year-old woman seeking due to acute / subacute onset dyspnea.
Past medical history significant for rectal cancer with metastasis to liver, lungs and brain. Previously hospitalized due to severe left sided pleural fluid.
Current vitalsigns: Sat 91% on 2L oxygen, p.90, BP 115/70. The journal shows a habitual BP of 140/70. Clinical examination reveals absent leftsided breath sounds and dull percussion.

Spine-sign, well-defined diaphragm and the absence of curtain-effect indicates a large amount of pleural fluid. A fluid gap is also seen apically. But was this the entire truth? One would expect a gradual onset dyspnea in this setting.

The right ventricle, located adjacent to the liver, seems overloaded basally. Inferior vena cava (IVC) seems plethoric (dilated with poor respiratory variation) signifying increased central venous pressure (CVP). What happens to the right ventricle if preload / returnvolume is increased? Ask the patient to take a deep breath. This generally also improves the subcostal image quality. Alternatively, try passive leg raise.

The basal part of the right ventricle is considerably dilated while the apex is hyperdynamic. Known as McConnell’s sign, it may indicate massive or submassive pulmonary embolism. But the question is if large amounts of unilateralt pleural fluid can induce respiratory variations in right ventricular load. A quick review of the literature comes back empty.
A left-sided pleural chest tube was set up and 1000cc of clear-red liquid drain after which the drainage was stopped. This was followed up by 500cc / 4hrs to avoid complications such as reexpansion-related pulmonary edema. The patient experienced immediate symptomatic relief and was admitted for further treatment. Sat 94%, p.80 and BP 120/70.
After a total of 2.5L fluid was drained, the patient noted a swelling of the lower extremities. Ultrasound showed bilateral DVT in common femoral veins. Pending thoracic CT according to LE protocol, a new cardiac echo was performed.

McConnell’s sign is accentuated by inspiration.
Central right-sided pulmonary embolism. In view of the brain metastasis, a reduced dose low molecular weight heparin was instituted BID.

One may ask if the CT is really necessary in this case. Bilateral DVT was already diagnosed and thus the indication for LMWH present. However, it was still deemed reasonable to perform the CT since the diagnosis was not quite clear and it may affect duration of treatment with anticoagulation.