Cardiovascular & Renal · Full case

DVT

NICE NG158Wells · D-dimer · USSPE red flag

Wells decides the pathwayThe two-level DVT Wells score stratifies "DVT likely" (≥2) vs "DVT unlikely" (≤1) and drives the whole pathway — it determines whether you go straight to ultrasound or use a D-dimer first

Likely → USS ≤4h (or interim anticoag)DVT likely (Wells ≥2): proximal leg vein ultrasound within 4 hours; if not available within 4 hours, give a D-dimer AND interim therapeutic anticoagulation and scan within 24 hours

Unlikely → D-dimerDVT unlikely (Wells ≤1): D-dimer (with results within 4 hours, or interim anticoagulation if delayed). Negative D-dimer excludes DVT; positive → proximal USS within 4 hours

DOAC first-lineConfirmed DVT: anticoagulate — apixaban or rivaroxaban first-line (NICE NG158), for at least 3 months. No bridging needed. Choose by renal function, comorbidity, adherence and patient factors

D-dimer ≠ diagnosisD-dimer is sensitive but not specific — raised in infection, malignancy, pregnancy, surgery, age. Use it only to rule OUT in the "unlikely" group; never to rule in. A negative D-dimer in a "likely" patient does not exclude DVT

Provoked vs unprovokedProvoked (surgery, immobility, pregnancy, hormones, cancer, long-haul travel) vs unprovoked — determines anticoagulation duration and the need to consider occult cancer and thrombophilia in unprovoked cases

Unprovoked → think cancerUnprovoked VTE can be the first sign of occult malignancy. NICE NG158: review history and examination, and do baseline bloods (FBC, calcium, LFTs), urinalysis and a chest X-ray; investigate further only if clinically indicated — don't ignore the cancer association

Breathless = ?PEDVT can embolise. Pleuritic chest pain, breathlessness, haemoptysis, tachycardia or hypoxia → suspect pulmonary embolism; haemodynamic instability is a medical emergency requiring immediate admission

📋 Clinical Stem — DVT

A 46-year-old woman with 3 days of a painful, swollen right calf two weeks after a long-haul flight, who is otherwise well but quietly worried about a clot

Grace Adeyemi, 46, presents with 3 days of an aching, swollen right calf that came on without injury. It is warm and tender, and the leg looks bigger than the left. She flew back from Lagos (an 8-hour flight) two weeks ago and has been less active since with a sprained ankle. She takes the combined oral contraceptive pill and is a non-smoker. She has no breathlessness, chest pain or haemoptysis. She is worried because a colleague "had a clot that went to the lungs." She has had some recent unintentional weight loss she attributes to a diet, and is otherwise well.

This stem tests the ability to: recognise the clinical picture of a possible DVT and apply the two-level Wells score to choose the correct pathway (USS within 4 hours if "likely"; D-dimer first if "unlikely", with interim anticoagulation if scanning is delayed); exclude pulmonary embolism (breathlessness, chest pain, haemoptysis, instability); identify provoking factors (flight, immobility, oestrogen-containing contraception) and address them (stop the COCP, switch to a non-oestrogen method); anticoagulate appropriately with a DOAC for confirmed DVT; and consider occult malignancy and thrombophilia where the event is unprovoked. The SCA challenge is communicating uncertainty and the testing pathway clearly while managing the patient's anxiety and the contraception implications.

Scenario A — Provoked DVT (this stem) Long-haul flight + immobility + COCP. Wells, USS pathway, DOAC ≥3 months, stop COCP and switch contraception; address modifiable factors; safety-net for PE.

Scenario B — Unprovoked DVT No identifiable provoking factor. Anticoagulate; consider extended anticoagulation; review for occult cancer (history/exam, FBC, calcium, LFTs, urinalysis, CXR) and consider thrombophilia testing in selected cases.

Scenario C — Suspected PE DVT symptoms + pleuritic chest pain/breathlessness/haemoptysis/tachycardia/hypoxia. PE Wells + pathway; haemodynamic instability → emergency admission.

Scenario D — DVT in pregnancy Wells/D-dimer not validated; proceed to USS; treat with LMWH (not DOAC/warfarin); obstetric/haematology input.

Scenario E — DVT mimics Cellulitis, ruptured Baker's cyst, calf muscle tear/haematoma, chronic venous insufficiency, lymphoedema, superficial thrombophlebitis. Bilateral swelling → cardiac/renal/hepatic or IVC/pelvic obstruction.

Key variables to adapt for Wells category (likely vs unlikely → USS vs D-dimer); PE features; provoked vs unprovoked (duration, cancer/thrombophilia work-up); pregnancy (LMWH, no DOAC); oestrogen contraception/HRT; renal function and bleeding risk (DOAC choice); proximal vs distal; recurrence; massive/phlegmasia (limb-threatening); active cancer (LMWH/DOAC choice).

Steps:

Step 1

History — The Leg · Wells Factors · Exclude PE · Provoking Factors · ICE

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The history simultaneously builds the Wells score (which chooses the diagnostic pathway), screens for pulmonary embolism (the dangerous complication), and identifies provoking factors that shape treatment duration and the cancer/thrombophilia question. Grace's flight, immobility and oestrogen-containing pill are provoking factors; her quiet mention of weight loss is a thread to pull in case this is the rare unprovoked event heralding cancer.

🎓 SCA framing — explain the "test then treat" pathway and the uncertainty

"Your symptoms could well be a clot in the leg, and we have a clear pathway to check — a score, sometimes a blood test, and a scan. I'll explain each step. The most important thing first is to make sure it hasn't affected your breathing."

Grace is anxious about a clot reaching the lungs. The skill is to take that fear seriously (exclude PE explicitly), explain the structured pathway, and be honest that we test before we can be certain.

1A — The leg, the Wells factors and the PE screen

Question	Why it matters	Changes what?
🟢 OPEN QUESTION"Tell me about the leg — when it started, and whether anything brought it on."	Captures onset, laterality and the story. Unilateral calf pain/swelling that came on without trauma is the classic DVT picture; bilateral swelling points elsewhere (cardiac/renal/hepatic, or IVC/pelvic obstruction). The narrative also surfaces provoking factors and the patient's concern.In SCA: eliciting laterality, the provoking story (flight/immobility) and the PE screen in the opening exchange is efficient, safe data-gathering.	Unilateral → DVT likely; bilateral → systemic/obstructive
Wells clinical factors"Is the whole leg swollen? Is the calf much bigger than the other side? Any tenderness along the deep veins? Any pitting?"	The two-level Wells score combines clinical features (active cancer, immobilisation/recent surgery, localised deep-vein tenderness, entire leg swollen, calf >3cm larger, pitting oedema, collateral superficial veins, previous DVT) and "alternative diagnosis as likely or more likely (−2)". The total (≥2 = likely; ≤1 = unlikely) chooses the pathway.	Wells ≥2 → USS pathway. Wells ≤1 → D-dimer first.	Wells score selects USS vs D-dimer
🚩 PE screen"Have you had any breathlessness, chest pain (especially on breathing in), coughing up blood, or palpitations?"	The safety core. A DVT can embolise to the lungs. Pleuritic chest pain, breathlessness, haemoptysis, tachycardia or hypoxia raise PE; haemodynamic instability (hypotension, collapse) is a medical emergency. Grace has none — but it must be asked and documented.	PE features → PE pathway / emergency admission if unstable.	Unstable PE → 999/admit
Provoking factors"Any recent long journeys, operations, illness keeping you in bed, the pill or HRT, pregnancy, or a previous clot?"	Provoked (surgery, immobility, long-haul travel, oestrogen-containing contraception/HRT, pregnancy, active cancer) vs unprovoked determines anticoagulation duration and the cancer/thrombophilia question. Grace has a flight, reduced mobility and the COCP — provoked. The COCP must be stopped and contraception switched.	Provoked → treat ≥3 months, address factor. Oestrogen → stop COCP/HRT, switch method.	Stop COCP; switch contraception
🚩 Occult cancer screen (esp. if unprovoked)"Any weight loss, change in bowel habit, bleeding, lumps, or feeling generally unwell?"	Unprovoked VTE can be the first manifestation of cancer. Grace mentions unintentional weight loss — worth clarifying (genuine diet vs unexplained). NICE NG158: in unprovoked VTE, review history and examination and arrange baseline bloods (FBC, calcium, LFTs), urinalysis and CXR; investigate further only if clinically indicated.	Unprovoked + red flags → cancer review (bloods, urinalysis, CXR) ± targeted investigation.	Unprovoked VTE → cancer review (NG158/NG12)
Bleeding risk & comorbidity"Any bleeding problems, ulcers, recent bleeds, liver or kidney problems? What other medicines do you take?"	Anticoagulation is the treatment, so assess bleeding risk, renal/hepatic function and interacting drugs up front — these guide DOAC choice and dose, and flag patients who need specialist input.	High bleeding risk / renal impairment → tailor anticoagulant; specialist advice.	Bleeding/renal status → DOAC choice

1B — Red flags

🚨

Red Flags — the dangerous ends of DVT

Red flag	Why dangerous	Action
Pulmonary embolism — breathlessness, pleuritic chest pain, haemoptysis, tachycardia, hypoxia	PE is the lethal complication of DVT; massive PE causes haemodynamic collapse and death.	Haemodynamically unstable → 999/immediate admission; otherwise urgent PE pathway/assessment
Phlegmasia (massive proximal DVT) — severely swollen, painful, discoloured limb ± compromised perfusion	Limb-threatening; risk of venous gangrene and compartment syndrome.	Emergency vascular/admission; urgent anticoagulation ± thrombolysis
Bilateral leg swelling / suspected IVC or pelvic obstruction	Bilateral DVT or extrinsic compression (pelvic mass/malignancy) needs imaging beyond a leg scan.	Urgent imaging; consider pelvic/abdominal cause
Unprovoked VTE with cancer warning features	May be the presenting sign of occult malignancy.	Cancer review (FBC, calcium, LFTs, urinalysis, CXR); targeted 2WW if indicated (NICE NG12)
DVT in pregnancy	Wells/D-dimer not validated; untreated VTE risks PE; DOACs/warfarin contraindicated.	Proceed to USS; treat with LMWH; obstetric/haematology input
High bleeding risk needing anticoagulation	Anticoagulation in a high-bleeding-risk patient requires careful balance and sometimes specialist input.	Assess risk/benefit; haematology advice; tailor agent/duration

1C — ICE

💭 Ideas

"What do you think might be going on — and is there something particular you're worried about?"

Grace has connected her symptoms to her colleague's clot and the flight. Engaging her (largely correct) model lets you validate her for coming in promptly and explain the pathway, rather than talking past a fear she already holds.

😟 Concerns

"Is it the idea of a clot going to the lungs that's worrying you most?"

Naming her fear of PE lets you address it directly — explaining that you are specifically checking her breathing now, and that prompt treatment greatly reduces the risk — which is more reassuring than generic comfort.

🎯 Expectations

"What were you hoping we'd do today?"

She may expect an immediate scan or an instant answer. Naming this lets you set realistic expectations about the timed pathway (Wells, possible D-dimer, ultrasound) and the possibility of interim anticoagulation if the scan is delayed.

1D — Psychosocial context

A suspected clot is frightening — patients have often heard of someone who died of a PE. Alongside the diagnostic pathway sit two human conversations: stopping the combined pill (and sorting alternative contraception, with its own implications) and, if DVT is confirmed, starting months of anticoagulation with its bleeding precautions and lifestyle adjustments. Handling the anxiety with clear, staged information, and treating the contraception and anticoagulation conversations as shared decisions, turns a scary episode into a managed one.

😟 Fear of PE

Acknowledge it and act on it visibly by screening the chest; explain that treatment markedly reduces embolism risk.

"I can hear the worry about a clot reaching the lungs — that's exactly why I've checked your breathing carefully, and why, if it is a clot, we start treatment quickly to stop that happening."

💊 The pill conversation

The COCP must stop; plan alternative contraception sensitively (progestogen-only/non-hormonal), as this affects her life.

"If this is a clot, the combined pill needs to stop because the oestrogen adds to the risk. Let's sort a different method that's safe — there are good options that don't carry the same risk."

🩸 Living with anticoagulation

Explain duration, bleeding precautions and what to watch for, framed as manageable.

"If confirmed, you'd take a blood-thinning tablet for at least three months. Most people get on with life normally — I'll go through the things to be careful about and the signs of bleeding to look out for."

🔎 The weight-loss thread

If the event is unprovoked or there are warning features, explain the cancer review without alarm.

"You mentioned losing some weight — because a clot can occasionally be the body's first warning sign, I'd like to do a few routine checks to be thorough. It's precautionary, not because I'm expecting to find anything."

🎓 SCA Checkpoint — Step 1TasksRelating to OthersGlobal Skills

Key phrases that score

"Any breathlessness, chest pain on breathing in, or coughing up blood?" — the PE screen, every time.

"There's a scoring system that tells us whether to go straight to a scan or do a blood test first." — explains the Wells pathway.

"If it is a clot, the combined pill needs to stop and we'll switch you to a safe alternative." — addresses the provoking factor.

Deductions

Not screening for PE
Not applying/realising the Wells pathway (USS vs D-dimer)
Forgetting to stop the COCP / arrange alternative contraception
Missing the unprovoked-VTE cancer consideration

🔴 Red

PE not screened; Wells/pathway not used; COCP not stopped; D-dimer used to "rule in"; no safety-net

🟠 Amber

DVT suspected; some Wells factors; pathway partly correct; COCP addressed; cancer/thrombophilia not considered; ICE partial

🟢 Green

Wells applied correctly → correct pathway (USS/D-dimer ± interim anticoag); PE screened; COCP stopped + contraception switched; provoked/unprovoked addressed with cancer review where relevant; ICE all three; safety-net

Step 2

Triage — Emergency (PE / Phlegmasia) · Urgent (Wells Pathway) · Routine

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DVT itself is urgent, not routine — the triage task is to catch the embolic and limb-threatening emergencies, and otherwise to start the timed Wells-based diagnostic pathway promptly (with interim anticoagulation if scanning is delayed).

🔴 Emergency

Same day / 999

Immediate action

Haemodynamically unstable PEHypotension/collapse/hypoxia → 999/immediate admission
Phlegmasia / threatened limbMassively swollen, discoloured, compromised limb → emergency vascular
Suspected PE (stable)PE Wells + urgent pathway/assessment

🟠 Urgent

Hours (timed pathway)

NG158 pathway

DVT likely (Wells ≥2)Proximal USS ≤4h; if delayed → D-dimer + interim anticoag, scan ≤24h
DVT unlikely (Wells ≤1)D-dimer; if positive → USS ≤4h; interim anticoag if delayed
PregnancyProceed to USS; LMWH; obstetric input

🟢 Routine

After diagnosis

Ongoing care

Confirmed DVTDOAC ≥3 months; address provoking factors
Excluded DVTConsider alternative diagnosis; safety-net
Unprovoked reviewCancer review; duration decision; ?thrombophilia

🎓 SCA Checkpoint — Step 2Tasks

Triage rationale

"Your breathing is fine and the leg, while painful, isn't threatened — so this is the urgent clot-pathway: a score, and a scan today (with a blood-thinner in the meantime if the scan can't happen within a few hours)."

Deductions

Treating a possible DVT as routine / next-week
Not arranging interim anticoagulation when the scan is delayed

Step 3

Examination — The Leg · Wells Signs · Chest · Exclude Mimics

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Examination quantifies the Wells signs, screens the chest for PE, and looks for the mimics — because cellulitis, a ruptured Baker's cyst and a calf tear all masquerade as DVT.

🦵 The leg

Sign	Why
Calf circumference (measure both, >3cm difference)	A Wells criterion; objective swelling.
Tenderness along deep veins, warmth, erythema, pitting oedema	Wells features; warmth/erythema also seen in cellulitis.
Dilated superficial (collateral) veins	A Wells criterion.
Whole-leg swelling vs calf only; bilateral?	Bilateral → systemic/obstructive cause.

🫁 Chest & mimics

Check	Why
Observations (HR, RR, SpO2, BP)	Tachycardia/hypoxia/hypotension → PE.
Cellulitis features	Spreading erythema, fever, portal of entry → cellulitis (can coexist).
Ruptured Baker's cyst / calf tear	Sudden onset, bruising, popliteal fullness; recent exertion.
Skin / chronic changes	Venous insufficiency, lymphoedema.

🎓 SCA Checkpoint — Step 3TasksGlobal Skills

Narration that scores

"I'll measure both calves, feel along the deep veins, check for warmth and swelling, and check your pulse, breathing and oxygen — to score the likelihood and make sure your chest is fine."

Deductions

Not measuring calf circumference / objective Wells signs
Not checking observations for PE; missing cellulitis

Step 4

Investigations — Wells → D-dimer / USS · Baseline & Cancer Bloods

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Investigation in DVT is a protocol, not a free-for-all: the Wells score selects the next test, D-dimer rules out only in the "unlikely" group, proximal ultrasound confirms, and baseline bloods plus a cancer review accompany an unprovoked event.

🧭 The diagnostic protocol

Step	Action
Two-level Wells	≥2 = DVT likely; ≤1 = DVT unlikely.
Likely (≥2)	Proximal leg vein USS within 4 hours; if not possible → D-dimer + interim anticoagulation, USS within 24 hours.
Unlikely (≤1)	D-dimer (results within 4h, or interim anticoagulation). Negative → DVT excluded. Positive → USS within 4 hours.
Negative USS but positive D-dimer (likely)	Stop interim anticoagulation; repeat USS in 6–8 days.

🧪 Baseline & cancer review

Test	Why
FBC, U&E, LFTs, coagulation	Baseline before anticoagulation; renal/hepatic function guides DOAC.
Calcium, urinalysis, CXR	Part of the NICE NG158 occult-cancer review in unprovoked VTE.
Targeted cancer investigation	Only if clinically indicated by history/exam/initial results (e.g. age-appropriate screening, symptom-directed 2WW).
Thrombophilia testing	Consider in selected unprovoked cases (e.g. planning to stop anticoagulation, family history) — usually specialist-led.

💬 "Can't you just do a D-dimer and tell me?"

"The D-dimer is a useful blood test, but it's only good at ruling a clot OUT, and only when the clinical likelihood is low. Lots of things raise it — even being a bit older or having an infection — so a positive result doesn't confirm a clot. Because your score makes a clot quite likely, the right next step for you is a scan rather than relying on the blood test."

🎓 SCA Checkpoint — Step 4Tasks

Key reasoning

"Your score puts you in the 'likely' group, so you go straight to a scan. If the scan can't happen within four hours, I'll give a blood-thinner to cover you until it does."

Deductions

Using D-dimer to "rule in", or in a "likely" patient to exclude DVT
Not arranging interim anticoagulation for delays
Ignoring baseline bloods / unprovoked cancer review

Step 5

Diagnosis — Confirmed DVT · Provoked vs Unprovoked · The Mimics

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Confirm or exclude DVT on ultrasound, classify it provoked or unprovoked (which drives duration and the cancer question), and name the mimic if DVT is excluded.

Diagnosis	Discriminating features
Proximal DVT	USS-confirmed thrombus in popliteal/femoral veins — anticoagulate.
Distal (calf) DVT	Confined to calf veins; manage per local policy (anticoagulate or surveillance scan).
Provoked DVT	Identifiable transient factor (surgery, immobility, flight, oestrogen, pregnancy) — Grace; usually ≥3 months.
Unprovoked DVT	No factor; consider extended anticoagulation + cancer/thrombophilia review.
Cellulitis	Spreading erythema, fever, portal of entry; can coexist with DVT.
Other mimics	Ruptured Baker's cyst, calf muscle tear/haematoma, venous insufficiency, lymphoedema, superficial thrombophlebitis.

🚩 The discipline — classify the event, don't just treat it

Confirming a DVT is only half the job. Whether it is provoked or unprovoked changes how long anticoagulation continues and whether you must consider occult cancer and thrombophilia. For Grace, the flight, immobility and oestrogen pill make this a provoked DVT — at least 3 months of anticoagulation, stop the COCP, address mobility — but the unintentional weight loss still earns a basic cancer review to be safe.

🎓 SCA Checkpoint — Step 5Tasks

Explaining it plainly

"The scan shows a clot in the deep vein of your leg. It was almost certainly triggered by the flight, being less active, and the pill — so we treat it for at least three months, stop the combined pill, and get you moving."

Deductions

Not classifying provoked vs unprovoked
Missing the cancer/thrombophilia review when unprovoked

Step 6

Referral — Emergency · Anticoagulation Service · Haematology · Cancer Pathway

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Confirmed uncomplicated DVT is largely managed via the local DVT/anticoagulation pathway. Referral is for the emergencies, the complex anticoagulation decisions, pregnancy, and the cancer pathway where the review raises concern.

Referral	Who / when	Urgency
🔴 Emergency admission	Unstable PE, phlegmasia/threatened limb.	Same day / 999
DVT / ambulatory pathway	Suspected/confirmed DVT — local same-day USS and anticoagulation service.	Same day
Haematology	Recurrent/unprovoked VTE, anticoagulation in renal/hepatic impairment or high bleeding risk, thrombophilia, duration decisions, antiphospholipid syndrome.	Soon
Obstetrics + haematology	DVT in pregnancy (LMWH).	Urgent
🟣 Cancer pathway	Where the unprovoked-VTE review or symptoms raise suspicion of malignancy → symptom-directed urgent (2WW) investigation.	2WW if indicated · NG12

🎓 SCA Checkpoint — Step 6Tasks

Pathway awareness

"I'll send you straight into our same-day clot pathway for the scan and to start treatment. If anything in your routine checks needs following up, we'll arrange that too."

Deductions

Not using the same-day DVT pathway
Prescribing a DOAC in pregnancy

Step 7

Management — Anticoagulation · Duration · Contraception · Safety-Net

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Management is anticoagulation (DOAC first-line) for an appropriate duration, addressing the provoking factor (stop the COCP, switch contraception), advice and a clear safety-net for PE and bleeding, and the unprovoked-VTE review where relevant.

7A — The plan

💊 Anticoagulation

Element	Detail
First-line	Apixaban or rivaroxaban (DOAC) — NICE NG158; no bridging; choose by renal function, bleeding risk, adherence.
Alternatives	LMWH then dabigatran/edoxaban; LMWH + warfarin if DOAC unsuitable; LMWH in pregnancy; consider DOAC/LMWH in active cancer.
Duration	At least 3 months; provoked with a transient factor → usually stop at 3 months; unprovoked / ongoing risk / cancer → consider extended anticoagulation after risk/benefit review.
Renal/bleeding	Dose by renal function; assess bleeding risk; review interacting drugs.

🛡️ Beyond the drug

Element	Detail
Stop COCP/HRT, switch contraception	Oestrogen is a provoking factor; switch to progestogen-only or non-hormonal method.
Mobilise & advise	Encourage mobility; travel advice for future flights; manage pain.
Safety-net (PE & bleeding)	"Seek urgent help if you become breathless, get chest pain, cough blood, or have significant bleeding."
Unprovoked review	Cancer review (bloods, urinalysis, CXR); duration and thrombophilia decision.
Follow-up	Review at ~3 months for duration decision; monitor adherence and bleeding; consider post-thrombotic syndrome.

🎓 SCA Checkpoint — Step 7TasksRelating to OthersGlobal Skills

A plan that scores

"Here's the plan: a blood-thinning tablet (apixaban) for at least three months, stop the combined pill and switch to a safe method, keep mobile, and seek urgent help if you get breathless, chest pain, cough blood or notice bad bleeding. We'll review at three months to decide how long to continue."

Deductions

No anticoagulation duration plan; no PE/bleeding safety-net
Failing to stop the COCP / arrange contraception
DOAC in pregnancy; ignoring renal/bleeding risk

"Doctor, my right calf's been swollen and really sore for three days now. I flew back from Lagos a couple of weeks ago and a colleague of mine had a clot that went to her lungs — I'm a bit scared it's the same thing."

Who you are

Grace Adeyemi, 46. Three days of an aching, swollen, warm right calf, no injury. The leg looks bigger than the left. You took an 8-hour flight from Lagos two weeks ago and have been less active since you sprained your ankle. You take the combined contraceptive pill, don't smoke. No breathlessness, no chest pain, no coughing blood. You're frightened because a colleague had a clot reach her lungs. If asked, you've lost a bit of weight recently but you've been dieting deliberately. You want to know if it's a clot and whether it's dangerous.

Hidden concerns (reveal if explored)

Fear of PE (main): you're scared it'll go to your lungs like your colleague's did. Being told the doctor has checked your breathing, and that treatment reduces that risk, reassures you.

The pill: you'll be surprised you have to stop it and will want to know about alternatives.

The scan/wait: you'd like an answer today; reassurance about the same-day pathway helps.

Clinical details if asked

Unilateral right calf swelling/pain, warm, tender; calf looks bigger than left; mild pitting
Onset gradual over 3 days; no trauma; reduced mobility after ankle sprain; 8-hour flight 2 weeks ago
On combined oral contraceptive pill; non-smoker; no previous clots; no family history of clots that you know of
No breathlessness, chest pain, haemoptysis, palpitations; not light-headed
Recent intentional weight loss (dieting); otherwise well; no other symptoms
No bleeding problems; no liver/kidney issues; on no other regular medication

Reactions at key moments

On the PE screen: relieved the doctor is checking your chest specifically.
On stopping the pill: "Oh — I'll need something else then?" → reassured by a clear alternative.
On anticoagulation: a bit daunted by months of tablets; reassured by clear explanation.
Challenge line: "Can't you just do a blood test now and tell me if it's a clot?"

"Is it going to go to my lungs like my colleague's did? And can't you just do a quick blood test to tell me right now if it's a clot?"

Resolution: Grace is reassured if the GP: (1) screens for and excludes PE explicitly and takes her fear seriously; (2) applies the Wells score and explains the correct pathway (likely → scan within 4 hours, with interim anticoagulation if delayed), including why a D-dimer alone isn't enough for her; (3) identifies the provoking factors and stops the COCP, arranging a safe alternative; (4) plans DOAC anticoagulation for ≥3 months with a clear duration review, and gives a PE/bleeding safety-net; (5) does a basic cancer review only if needed and frames it calmly. She's unsettled if PE is not addressed, the pathway is muddled, or the pill issue is missed.

🏥

Clinic Quick Reference

DVT — Clinical Decision Framework

NICE NG158 · Wells → USS/D-dimer · DOAC · Provoked vs unprovoked

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🚦 1 — The pathway

Suspected DVT → two-level Wells

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🔴 Emergency first

Unstable PE → 999
Phlegmasia / threatened limb

Admit

🟠 Likely (≥2)

Proximal USS ≤4h
If delayed → D-dimer + interim anticoag, USS ≤24h

Scan

🟢 Unlikely (≤1)

D-dimer; negative excludes
Positive → USS ≤4h

D-dimer

💊 2 — Treat & classify

Confirmed DVT: DOAC (apixaban/rivaroxaban) first-line ≥3 months; LMWH in pregnancy. Classify: provoked (flight/immobility/oestrogen/surgery) → usually 3 months + address factor (stop COCP, switch contraception); unprovoked → consider extended anticoagulation + occult-cancer review (FBC, calcium, LFTs, urinalysis, CXR) ± thrombophilia. Safety-net for PE and bleeding; review at 3 months.

🎓

SCA Quick Reference

DVT — Consultation Playbook

Wells pathway · exclude PE · DOAC · stop the oestrogen

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🎯 The three pivots that pass this case

1 · Exclude PE

Always screen breathlessness/chest pain/haemoptysis/instability — PE is the lethal complication.

2 · Wells decides

Likely → USS ≤4h (interim anticoag if delayed); unlikely → D-dimer (rule out only). DOAC ≥3 months once confirmed.

3 · Classify & address

Provoked vs unprovoked drives duration + cancer/thrombophilia review. Stop the COCP and switch contraception.

⛔ Don't use D-dimer to "rule in", or to exclude DVT in a "likely" patient · Don't forget interim anticoagulation if the scan is delayed · Don't miss PE · Don't leave the combined pill running · In unprovoked VTE, do the occult-cancer review · No DOAC in pregnancy (LMWH)

DVT · GP Clinical Reasoning Framework v2 · NICE NG158 Venous thromboembolic diseases · NICE CKS DVT · NICE NG12 Suspected cancer (occult malignancy in unprovoked VTE) · FSRH (contraception & VTE)

Two-level Wells selects the pathway: likely (≥2) → proximal USS ≤4h (interim anticoag + D-dimer if delayed); unlikely (≤1) → D-dimer (rule out only) → USS if positive · DOAC (apixaban/rivaroxaban) first-line ≥3 months; LMWH in pregnancy · Always exclude PE; instability = emergency · Provoked vs unprovoked drives duration and the occult-cancer review (FBC, calcium, LFTs, urinalysis, CXR) · Stop oestrogen-containing contraception/HRT and switch method · Safety-net for PE and bleeding

Teaching clinicians why each step matters — not just what to do · Always consult current NICE NG158/CKS and NG12 guidance · Clinical judgement takes precedence over any framework

DVT

Red Flags — the dangerous ends of DVT

😟 Fear of PE

💊 The pill conversation

🩸 Living with anticoagulation

🔎 The weight-loss thread

Same day / 999

Hours (timed pathway)

After diagnosis

🚩 The discipline — classify the event, don't just treat it

🎭 Patient actor brief — click to practise

Who you are

Hidden concerns (reveal if explored)

Clinical details if asked

Reactions at key moments