Brief Answer:
Further evaluation needed

Detailed Answer:
Hi,
I have gone through your query and understand your concern,

Yes, you are right, although this seems like a Vascular pathology at a glance, some other possibilities are there too (a deep-seated infection most notably, which can be the reason why such strong antibiotics like Vancomycin is running).

It's ok if they don't have the instant access to the Cardiologist.

First of all, in order to confirm the diagnosis, a few basic work-ups need to be done. A complete hemogram, Procalcitonin level, liver, and kidney function assay along with few other tests like a 12 lead ECG, Chest X-ray, Color Doppler Ultrasound study of the arterio-venous system of the entire left Leg as well as the unaffected leg (this is specifically to be done to rule out any blood-clot/Veno-arterial structural pathology/occlusion which can cause such pain).All of these blood investigations can be done in their labs while the doppler study can be run bed-side only by an experienced radiologist. This will help to pinpoint the diagnosis which will help to treat the specific cause.

Unless there's any shortness of breath, chest-tightness like symptoms (since you haven't mentioned any, I assume they are not present), there's no urgent need for a Cardio/Pulmonologist.

Pain in both the situation (Vascular as well as Infection) can be intractable. in fact, such low BP of 80/40mmhg will not allow stronger analgesics (even use of Morphine should be done under strict medical supervision). However, in order to achieve greater pain relief, additionally, Diclofenac and Naproxen shots/ low-sustained release intra-dermal patches can also be added.

If still not relieved, then further pain control needs to be done in an ICU set-up with continuous monitoring and I.V infusion of analgesics.

Please discuss all these with your doctor.

Take Care
Kind Regards
Dr. Arnab Banerjee,
Critical Care Specialist

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