Answer:

This ECG is incredibly low voltage. Low voltage ECG when <5 mm in limb leads. In addition, there is beat to beat variation in QRS amplitude consistent with electrical alternans - commonly associated with anterior-posterior swinging of the heart in a pericardial effusion. A patient with ECG showing low voltage + electrical alternans raises strong concern for pericardial effusion. In this patient with lung cancer and prior radiation to the chest, an effusion would most likely be malignant pericardial effusion. The presence of JVD on exam and dyspnea raises concern for tamponade.

Our next step within the clinic would be to perform pulsus paradoxus. Using your stethoscope and your manual BP cuff, inflate the cuff until all Korotkoff are absent, then slowly release the pressure from the cuff while listening. The first sounds auscultated will be heard only during expiration. Record this number. Continue to release the pressure and note the pressure at which both sounds are heard during inspiration and expiration. Pulsus paradoxus is the exaggerated ventricular interdependence and is characterized by a fall in pressure of >10 mm.

It is important to ensure the patient does not alter their normal breathing pattern. They should be taking even regular tidal volumes.

The patient should be referred to ED for urgent TTE:

Answer:

This is a wide differential because this patient is at risk for so many things. Let’s use the CPSolver’s AMS MIST mnemonic to go through this. M is for mimics and metabolic. In terms of mimics, it is imperative to determine if this patient is truly altered or if they are dysarthric or aphasic. This patient is at risk for brain metastasis 2/2 small-cell lung cancer, these more often present with headaches and focal neurologic findings, and less commonly altered mental status. Metabolic etiologies are high on the list for this patient - looking at the renal panel, this patient is at risk for sodium disturbances from SIADH, hypercalcemia of malignancy, and tumor lysis syndrome. I is for infection. This patient is at risk for all the common causes of AMS in patients with an infection (pneumonia, UTI, etc), but now we also need to be concerned about neutropenic fever and fungal infection. S is for structural, again are there any metastases or is there any reason for bleeding, specifically SDH. Finally, T is for Toxin. In this case, this patient could have narcotics prescribed for pain that he overdosed on, but what jumps to mind is the PDL1 inhibitor - looking through common adverse effects, cerebritis is not a common side effect of the PDL1 inhibitors, but something to think about.

Answer:

This patient is presenting with:

Hyponatremia
Hyperkalemia
Hyperphosphatemia
Hypocalcemia
Hyperuricemia
Acute kidney injury
AGMA

This constellation of electrolyte derangements (hyperK, hypoCa, hyperPO4, hyperuricemia) should raise concern for Tumor Lysis Syndrome (TLS). She has Sjogren’s Syndrome which raises her risk for non-Hodgkin’s lymphoma (likely related to her chronic lymphocyte activation). We commonly think of TLS during initiation of chemotherapy, but spontaneous TLS can occur with aggressive lymphomas and leukemias. She likely developed TLS from undiagnosed lymphoma and her hyperkalemia produced an arrhythmia leading to her syncopal presentation.

Your next steps should be to obtain an ECG, give calcium gluconate, and begin rapid hyperkalemia reversal. You will need to begin TLS treatment with aggressive hydration and rasburicase.