Blood Clots: The Signs, and Which Ones Are Emergencies

Call 911 now if there is sudden breathlessness, chest pain that is worse when
you breathe in, coughing up blood, a racing heart, or faintness. A clot that
has travelled to the lungs presents that way, and it is a life-threatening
emergency.

Come in today if one leg or arm becomes swollen, painful, warm or discoloured
— particularly if it is only one side. That is how a deep clot presents, and the
reason to be seen quickly is precisely to stop it becoming the paragraph above.

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Three different things called "a clot"

The post this article replaces was about superficial clots, and conflating the
three is the commonest and most consequential confusion in this subject.

1. A superficial clot — in a vein just under the skin

A clot in a vein just under the skin. A firm, tender, cord-like lump you can
feel, with redness along its line, often in a varicose vein or where a drip
has been.

It is painful, it is usually not dangerous, and it generally settles with simple
measures. But it is not always as isolated as it looks, and it can sit
alongside a deeper clot — which is why "probably superficial" is a conclusion
for an examination rather than a self-assessment, especially the first time.

Be seen if it is spreading, the whole limb swells, you have a fever, it is
near the groin or the top of the thigh, or you have had a clot before.

2. A deep clot in a leg or arm — an emergency today

Deeper, larger veins, and the risk is that part of it travels to the lungs.

• Swelling, usually of one limb — the asymmetry is the most useful single
  sign
• Aching, cramping or tightness, often in the calf, often worse standing or
  walking
• Warmth, and skin that looks red, purple or darker than the other side
• Veins that stand out more than usual
• It can also be almost silent — a little swelling and nothing else

Do not wait to see whether it settles, and do not rub or massage it.

3. A clot that has reached the lungs — call 911

• Sudden breathlessness, at rest or on minimal effort
• Chest pain that sharpens when you breathe in
• Coughing up blood
• A fast or pounding heart, light-headedness, fainting
• A sense of anxiety or doom that arrives with the physical symptoms

This can happen without any leg symptoms at all, which is why the breathing
signs are worth knowing on their own.

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Who is at higher risk, and when

Worth knowing because risk comes in episodes, and the episodes are
predictable:

• After surgery, especially orthopaedic, and for weeks afterwards rather
  than days
• Any period of immobility — a plaster cast, an illness in bed, a long
  hospital stay
• Long journeys, and in this part of Arizona that means the long drive as
  much as the flight. Four hours to the coast counts.
• Pregnancy and the weeks after giving birth
• Cancer, and some of its treatments
• Oestrogen-containing contraception or hormone therapy, particularly
  alongside smoking
• A previous clot, or a family history of one. This is the strongest single
  factor and it should lower your threshold permanently.
• Dehydration — which in an Arizona summer is easier to reach than most
  people think, and stacks with everything above

If you are in one of those windows and a leg swells, treat it as the clot
until somebody tells you otherwise.

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What happens when you arrive here

This is a presentation where the diagnosis genuinely cannot be made by
examination alone, and where having the tools in the building decides whether
you get an answer tonight.

• A physician sees you — board-certified, every visit, at every hour.
• Ultrasound, called in from a mobile service, which is how a deep leg clot is
  found or ruled out.
• CT on site, which is how a clot in the lungs is looked for.
• Laboratory work in the building, including the blood tests used to decide
  whether imaging is needed at all.
• A critical care room here for the presentations that need one.
• Monitoring for up to 24 hours if you need watching rather than admitting.

An urgent care cannot do any of the three tests above, which is why this is
one of the clearest cases on the whole site for coming to an emergency room
rather than somewhere cheaper — not because we prefer it, but because the
alternative is being sent on and starting again.

If you need admission or hospital-level inpatient care, we stabilise you here
and arrange the transfer. We are an emergency room, not a hospital, and a
significant clot often ends in a transfer.

What helps us most: when the symptoms started, whether you have had a clot
before, any recent surgery, illness, immobility or long journey, whether you
take a blood thinner, and — if you do — whether you have missed any doses.

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What not to do

• Do not massage, rub or apply heat to a painful swollen leg.
• Do not "walk it off" on the assumption that it is a cramp, if the leg is
  also swollen or warm.
• Do not stop or start a blood thinner on your own judgement, and do not
  take someone else's. If you have missed doses, tell us — it changes the
  assessment and nobody will be annoyed.
• Do not wait for leg symptoms before taking the breathing signs seriously.
  They occur alone.

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El Mirage ER — open 24 hours a day, 7 days a week, 365 days a year.
12000 N El Mirage Rd, El Mirage, AZ 85335 · (480) 237-4922
Walk in. No appointment, no referral.
If this is a medical emergency, call 911.

This article explains when to seek emergency care. It is not medical advice and
cannot account for your history, your medications, or what is happening to you
now. If you are unsure, call us or call 911.

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Sources

The guidance in this article about when to seek emergency care is drawn
from these public sources. Each one is linked so you can read it yourself.

• MedlinePlus (National Library of Medicine) — Deep Vein Thrombosis — https://medlineplus.gov/deepveinthrombosis.html

This article is general information, not a diagnosis, and it cannot account
for your history or medications. If you are unsure, call us on (480) 237-4922
or come in. If it might be an emergency, treat it as one and call 911.

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