Brief Answer:
he need to consult a physician.

Detailed Answer:
Hello.

Welcome to Healthcare Magic.

I read carefully your query.

The difference of blood pressure between his arms is considerable.
Small differences in blood pressure can be normal but differences of more than 20 mm Hg for systolic pressure or more than 10 mm Hg for diastolic pressure may be a sign of an underlying problem.
The most common cause of this big difference of blood pressure between arms is the obstruction or progressive narrowing of the main arteries of the arm,in the arm with higher blood pressure.This is called peripheral artery disease .

Common symptoms of this condition are : pain or discomfort in arm when doing daily tasks or work , that goes away when resting the arm.
Pain in finger or cold finger that can turn blue or pale,slow-growing fingernails ,the skin of the arm can look pale and with no hair, are some other symptoms.

The symptoms you describe of hand numbness ,and the characteristic distribution in the 3-5 th finger ,loss of grip are not related to the circulation problem.The symptoms are indicative for a compression of ulnar nerve ,most commonly in elbow.These symptoms are very typical for this condition.
In this case NSAIDs (Ibuprofen ,Tylenol, Naproxen ) can help with the symptoms .He should avoid activities that require him to keep the arm bent for long periods of time and try to keep the arm straight at night when sleeping.
Your husband need to consult a physician and get examined.The doctor will measure the blood pressure in both arms again and if this big difference between the arms persist ,the doctor will order further investigations including an echo doppler of the arm arteries.

The doctor also will evaluate the function of the hand and if ulnar nerve is affected.He may order some tests in order to evaluate the ulnar nerve function like Nerve conduction studies.

Hope it helps.
Let me know if you need further help.

Kind regards,
Dr.Rovena Murati

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