cardio.dvt.post-orthopedic-arthroplasty.v1PRODUCTION

cardio.dvt.post-orthopedic-arthroplasty.v1

Post-orthopedic-arthroplasty DVT (post-THA/TKA/hip-fracture; ASA vs DOAC vs LMWH per AAOS 2025 + ACCP)

cardiologyacuteadult

Hard-required inputs

0 / 10

Care setting:

Encounter flow

11/12 authored

Canonical 12-phase frame with authored status for this dossier.

Current phase

Frame

Detailed

Post-orthopedic-arthroplasty DVT = highest-VTE-risk surgical class with extended prophylaxis (35 d hip / 12 d knee per AAOS 2025 + ACCP 2021) and tiered drug choice (ASA non-inferior to DOAC for standard-risk per EPCAT-II; DOAC or LMWH for high-risk; LMWH for hip-fracture surgery). Treatment of established post-op DVT follows standard provoked-VTE 3-mo arc but distinguishes symptomatic vs surveillance-detected presentations

Inputs

Actions

Advance rule

Set

Advance when

Post-arthroplasty DVT framed

Patient inputs (11)

age*demographic • CONTEXT

Older arthroplasty patients (peak elective THA/TKA 65-75 yr) have additive VTE + bleed risk; falls + frailty influence drug choice + duration

sex*demographic • CONTEXT

Female + post-arthroplasty + OCP / HRT compounds risk (most should hold ≥4 wk pre-op per AAOS); pregnancy in arthroplasty cohort rare but possible (revision arthroplasty in young women)

prophylaxis_regimen_and_adherence*history • CONTEXT

not present

Document specific prophylactic agent (ASA, rivaroxaban, apixaban, enoxaparin, dabigatran, warfarin), dose, start date, planned duration, and patient-reported adherence; breakthrough on documented adherence flags prophylaxis failure + thrombophilia consideration

additive_vte_risk_factors*history • CONTEXT

not present

Prior VTE, active cancer, BMI >40, known thrombophilia, hip-fracture surgery (vs elective THA/TKA), prolonged immobility, age >75 — these shift away from ASA monotherapy toward DOAC or LMWH

arthroplasty_type_and_date*history • ENTRY

not present

THA + hip-fracture surgery → 35-day extended prophylaxis window; TKA → 12-day prophylaxis window; revision arthroplasty often reverts to higher-risk THA/TKA-like prophylaxis; date anchors days-post-op for risk-window staging

leg_swelling*symptom • ENTRY

Cardinal symptom of proximal DVT; ipsilateral post-op swelling makes physical-exam alone unreliable; ALWAYS confirm with US not just calf-circumference

compression_us*imaging • INITIAL_WORKUP

not present

Diagnostic anchor — femoral + popliteal compression; whole-leg US preferred given post-op patient may have proximal extension; D-dimer often baseline-elevated post-surgery (less useful as rule-out)

cbc*lab • INITIAL_WORKUP

Baseline platelet for AC bleed risk; HIT screen if heparin exposure + platelet drop >50% from baseline at 5-14 d (4T score); post-op anaemia common — informs AC bleed-risk weighting

bleed_risk*history • RED_FLAGS

not present

HAS-BLED + post-op surgical bleed risk + falls history + neuraxial-anaesthesia timing per ASRA 2018 — drives AC eligibility, mechanical-only prophylaxis decision, and timing of AC initiation post-op (typically 12-24 h after haemostasis)

creatinine*lab • TREATMENT

eGFR for DOAC dosing (apixaban: ≥2 of age ≥80, weight ≤60 kg, Cr ≥1.5 → 2.5 mg BID; rivaroxaban CrCl <30 caution); LMWH dose-reduction at CrCl <30; informs UFH preference if CrCl <15

neuraxial_anaesthesia_status_and_epidural_catheter_timinghistory • TREATMENT

not present

Spinal / epidural anaesthesia with indwelling catheter mandates strict AC timing per ASRA 2018 — LMWH 12 h before block; rivaroxaban 22-26 h before block; epidural removal coordinated 12 h after last LMWH dose; prevents spinal hematoma

* = hard-required. Engine cannot meaningfully run until these are filled.

Severity triggers (5)

5 need judgement

informationallife_threateningmassive_pe_within_record_window_post_arthroplasty
Post-major-orthopedic-surgery patient (THA / TKA / HFS) within 35-day RECORD prophylaxis window develops massive PE with sustained hypotension or cardiac arrest
Trigger could not be auto-evaluated — needs clinician judgement.
informationallife_threateningspinal_hematoma_after_neuraxial_anaesthesia_with_recent_AC
Sudden back pain + new lower-extremity neurologic deficit (weakness, sensory loss, urinary retention) in patient with recent neuraxial (spinal/epidural) anaesthesia + recent AC administration — spinal hematoma is a surgical emergency
Trigger could not be auto-evaluated — needs clinician judgement.
informationallife_threateninghit_with_limb_thrombosis_post_arthroplasty_on_lmwh
Platelet drop >50% from baseline 5-14 days into LMWH prophylaxis with new lower-extremity thrombosis — HIT with HITT (HIT-related thrombosis) confirmed by 4T score ≥6 + serotonin-release assay or anti-PF4 ELISA positive
Trigger could not be auto-evaluated — needs clinician judgement.
informationalseverebreakthrough_vte_on_adherent_prophylaxis_after_arthroplasty
New DVT or PE in post-arthroplasty patient with documented compliance with prophylactic regimen (rivaroxaban 10 mg daily, ASA 81 mg BID, enoxaparin 40 mg daily, apixaban 2.5 mg BID) — prophylaxis-failure scenario warrants escalation to treatment-dose AC + thrombophilia consideration + drug interaction review
Trigger could not be auto-evaluated — needs clinician judgement.
informationalmoderateasa_inappropriately_used_in_high_risk_arthroplasty_patient
High-risk arthroplasty patient (prior VTE, active cancer, known thrombophilia, BMI >40, hip-fracture surgery) inappropriately discharged on ASA monotherapy for prophylaxis — ASA insufficient in this risk band per AAOS 2025
Trigger could not be auto-evaluated — needs clinician judgement.

Workflow calculators

Run this disease's risk and dosing calculators inline.

RED_FLAGSrequiredDrives risk stratification

Loading…

Recommended regimen

Post-arthroplasty DVT — treatment-dose AC for symptomatic post-op DVT (3 mo provoked) PLUS framework for extended prophylaxis (35 d hip / 12 d knee per AAOS 2025 + ACCP 2021) and risk-tiered drug choice (ASA non-inferior to DOAC for standard-risk per EPCAT-II)

axis: post_arthroplasty_dvt_treatment_and_extended_prophylaxis

Selected axis "Post-arthroplasty DVT — treatment-dose AC for symptomatic post-op DVT (3 mo provoked) PLUS framework for extended prophylaxis (35 d hip / 12 d knee per AAOS 2025 + ACCP 2021) and risk-tiered drug choice (ASA non-inferior to DOAC for standard-risk per EPCAT-II)" by default fallback (first axis)

apixaban
first line
doac_factor_xa_direct
Treatment: 10 mg BID × 7 d → 5 mg BID × 3 mo; Extended prophylaxis: 2.5 mg BID × 35 d post-THA or × 12 d post-TKA per ADVANCE-2/3 • PO • BID
triggers: post_arthroplasty_symptomatic_dvt_treatment, post_arthroplasty_extended_prophylaxis_high_risk, asa_intolerance, apixaban_preferred_alternative
Treatment: AMPLIFY (Agnelli NEJM 2013 PMID 23808982) — apixaban first-line for established VTE; Prophylaxis: ADVANCE-2 (Lassen Lancet 2010 PMID 20206776) and ADVANCE-3 (Lassen NEJM 2010 PMID 21142528) — 2.5 mg BID superior to enoxaparin for prophylaxis; AAOS 2025 + ACCP 2021 first-line option
rxcui 1364430
rivaroxaban
first line
doac_factor_xa_direct
Treatment: 15 mg BID × 21 d → 20 mg daily × 3 mo; Extended prophylaxis: 10 mg daily × 35 d post-THA or × 12 d post-TKA per RECORD-1/2/3 • PO • BID then daily; 10 mg daily for prophylaxis
triggers: post_arthroplasty_symptomatic_dvt_treatment, post_arthroplasty_extended_prophylaxis_record_window, high_risk_arthroplasty_patient
Treatment: EINSTEIN-DVT (Bauersachs NEJM 2010 PMID 21128814); Prophylaxis: RECORD-1/2/3 (Eriksson NEJM 2008 PMID 18579812; Kakkar Lancet 2008 PMID 18582928; Lassen NEJM 2008 PMID 18579811) — rivaroxaban 10 mg daily superior to enoxaparin for prophylaxis; EPCAT-II (Anderson NEJM 2018 PMID 29466159) — ASA non-inferior to rivaroxaban for symptomatic VTE prevention after 5-d rivaroxaban lead-in
rxcui 1114195
aspirin
first line
antiplatelet_cox1
Prophylaxis: 81 mg PO BID × 30 d post-THA or × 14 d post-TKA after 5-day rivaroxaban or enoxaparin lead-in (per AAOS 2025 + EPCAT-II; standard-risk patients only) • PO • BID for prophylaxis (NOT for symptomatic DVT treatment)
triggers: post_arthroplasty_extended_prophylaxis_standard_risk_only, doac_intolerance_or_cost_constraint, epcat_ii_eligibility
EPCAT-II (Anderson NEJM 2018 PMID 29466159) — ASA 81 mg BID after 5-d rivaroxaban lead-in NON-INFERIOR to continued rivaroxaban for symptomatic VTE prevention after THA/TKA; AAOS 2025 Strong recommendation in standard-risk patients; do NOT use ASA monotherapy in high-risk patients (prior VTE, active cancer, thrombophilia, BMI >40, hip-fracture surgery); never substitute for treatment-dose AC in symptomatic established DVT
rxcui 243670
enoxaparin
first line
lmwh
Treatment: 1 mg/kg SC BID (1 mg/kg daily if CrCl <30); Prophylaxis: 40 mg SC daily (THA/TKA) or 30 mg SC q12h (HFS or extended); 35-d post-THA or 12-d post-TKA • SC • BID treatment; daily or q12h prophylaxis
triggers: post_arthroplasty_dvt_treatment, hip_fracture_surgery_prophylaxis, doac_contraindicated, pregnancy_in_revision_arthroplasty
ASH 2020 (PMID 33007077); ACCP 2021; AAOS 2025 — LMWH first-line option for high-risk arthroplasty patients and HFS; pre-op LMWH considered if HFS surgery delayed >12 h per HIP-ATTACK (Borges Lancet 2020 PMID 32325025)
rxcui 67108
dabigatran
second line
doac_direct_thrombin_inhibitor
Prophylaxis: 220 mg PO daily after 1-4 h post-op half-dose start × 35 d (THA) or × 10 d (TKA) per RE-NOVATE / RE-MODEL • PO • daily
triggers: post_arthroplasty_extended_prophylaxis_dabigatran_alternative, doac_class_alternative_when_factor_xa_inhibitor_contraindicated
RE-NOVATE / RE-MODEL — dabigatran 220 mg daily non-inferior to enoxaparin for prophylaxis; less commonly chosen than apixaban or rivaroxaban; CrCl <30 contraindication
rxcui 1037045
warfarin
comorbidity specific
vitamin_k_antagonist
5 mg daily; INR target 2-3 for treatment of established post-op DVT; for prophylaxis target INR 1.8-2.2 (less commonly used since DOAC era) • PO • daily
triggers: severe_renal_impairment_doac_unsafe, cost_constraint, antiphospholipid_syndrome_triple_positive, mechanical_heart_valve_overlap
TRAPS (Pengo Blood 2018) — warfarin > rivaroxaban in triple-positive APS; reasonable alternative if DOAC contraindicated; CrCl <15 → warfarin only; mechanical heart valve patients undergoing arthroplasty need warfarin bridge planning
rxcui 11289
heparin
comorbidity specific
unfractionated_heparin
80 U/kg IV bolus + 18 U/kg/h targeting aPTT 1.5-2.5× • IV • continuous
triggers: acute_severe_renal_impairment_egfr_below_15, peri_procedural_bridge, post_op_with_planned_return_to_OR, pe_with_hemodynamic_instability
Reversibility for acute peri-procedural management; ACCP 2021; reasonable for patients with planned return to OR or active bleed risk requiring rapid AC reversal
rxcui 235473
intermittent pneumatic compression (IPC)
add on
mechanical_prophylaxis
Continuous IPC bilateral lower extremities while in hospital (or non-operated leg if surgical-site precludes ipsilateral) • mechanical • continuous in hospital
triggers: all_arthroplasty_patients_in_hospital, pharmacologic_AC_contraindicated_active_bleed_or_severe_thrombocytopenia, as_adjunct_to_pharmacologic_AC
CLOTS-3 (Dennis Lancet 2013 PMID 23484795) — IPC reduces DVT in immobile patients; ACCP 2021 + AAOS 2025 — universal in-hospital adjunct; may serve as primary prophylaxis if pharmacologic AC contraindicated
fondaparinux
second line
pentasaccharide_factor_xa_inhibitor
Prophylaxis: 2.5 mg SC daily × 35 d post-THA or × 12 d post-TKA starting 6-8 h post-op (PENTHIFRA / EPHESUS) • SC • daily
triggers: hit_history_or_active_HIT_alternative, lmwh_intolerance
PENTHIFRA / EPHESUS — fondaparinux non-inferior to enoxaparin for arthroplasty prophylaxis; HIT-safe alternative; renal contraindication CrCl <30
rxcui 321208

outpatient playbook — drug actions (3)

1. STOP AC at 3 mo if substrate reversed (provoked-by-arthroplasty)
rxcui 1364430
AC stopped • PO • n/a
trigger: Standard provoked VTE pathway with substrate reversal
ACCP 2021 strong recommendation
2. EXTENDED low-dose AC if breakthrough on adherent prophylaxis or thrombophilia detected
rxcui 1364430
apixaban 2.5 mg BID extended-low-dose; OR rivaroxaban 10 mg daily extended • PO • BID or daily
trigger: Breakthrough VTE on adherent prophylaxis or confirmed thrombophilia
AMPLIFY-EXT (PMID 23216615); EINSTEIN-CHOICE (Weitz NEJM 2017 PMID 28316279)
3. enoxaparin pre-op for future arthroplasty (contralateral or revision)
rxcui 67108
40 mg SC daily prophylaxis OR 1 mg/kg SC BID treatment if active VTE history • SC • daily/BID
trigger: Future arthroplasty cycle
AAOS 2025 + ACCP 2021 — extended prophylaxis 35 d hip / 12 d knee for any new arthroplasty

Auto-drafted A&P note

outpatient

Subjective

- Possible entry pathways: Unilateral lower-extremity swelling, calf pain, or whole-leg swelling within 4-6 weeks of THA / TKA / hip-fracture surgery — post-arthroplasty VTE pretest probability sharply elevated; Documented THA / TKA / hip-fracture-surgery within preceding 6 weeks — anchor the surgical provoking factor and prophylaxis history (regimen + adherence + duration completed); New pleuritic chest pain, dyspnea, syncope, hemoptysis, or unexplained tachycardia within 35 days of THA / hip-fracture surgery (12 days for TKA) — concurrent PE screen mandated; CTPA if Wells PE > 4 or PERC fail.

Objective

- No vitals, labs, or imaging entered for this encounter.

Assessment

**Post-orthopedic-arthroplasty DVT (post-THA/TKA/hip-fracture; ASA vs DOAC vs LMWH per AAOS 2025 + ACCP)** (cardio.dvt.post-orthopedic-arthroplasty.v1).
Scope: Post-orthopedic-arthroplasty DVT = highest-VTE-risk surgical class with extended prophylaxis (35 d hip / 12 d knee per AAOS 2025 + ACCP 2021) and tiered drug choice (ASA non-inferior to DOAC for standard-risk per EPCAT-II; DOAC or LMWH for high-risk; LMWH for hip-fracture surgery). Treatment of established post-op DVT follows standard provoked-VTE 3-mo arc but distinguishes symptomatic vs surveillance-detected presentations

No severity triggers fired against current inputs.

Plan

Regimen axis: **Post-arthroplasty DVT — treatment-dose AC for symptomatic post-op DVT (3 mo provoked) PLUS framework for extended prophylaxis (35 d hip / 12 d knee per AAOS 2025 + ACCP 2021) and risk-tiered drug choice (ASA non-inferior to DOAC for standard-risk per EPCAT-II)**.
1. apixaban Treatment: 10 mg BID × 7 d → 5 mg BID × 3 mo; Extended prophylaxis: 2.5 mg BID × 35 d post-THA or × 12 d post-TKA per ADVANCE-2/3 PO BID (doac_factor_xa_direct, first line) — Treatment: AMPLIFY (Agnelli NEJM 2013 PMID 23808982) — apixaban first-line for established VTE; Prophylaxis: ADVANCE-2 (Lassen Lancet 2010 PMID 20206776) and ADVANCE-3 (Lassen NEJM 2010 PMID 21142528) — 2.5 mg BID superior to enoxaparin for prophylaxis; AAOS 2025 + ACCP 2021 first-line option
2. rivaroxaban Treatment: 15 mg BID × 21 d → 20 mg daily × 3 mo; Extended prophylaxis: 10 mg daily × 35 d post-THA or × 12 d post-TKA per RECORD-1/2/3 PO BID then daily; 10 mg daily for prophylaxis (doac_factor_xa_direct, first line) — Treatment: EINSTEIN-DVT (Bauersachs NEJM 2010 PMID 21128814); Prophylaxis: RECORD-1/2/3 (Eriksson NEJM 2008 PMID 18579812; Kakkar Lancet 2008 PMID 18582928; Lassen NEJM 2008 PMID 18579811) — rivaroxaban 10 mg daily superior to enoxaparin for prophylaxis; EPCAT-II (Anderson NEJM 2018 PMID 29466159) — ASA non-inferior to rivaroxaban for symptomatic VTE prevention after 5-d rivaroxaban lead-in
3. aspirin Prophylaxis: 81 mg PO BID × 30 d post-THA or × 14 d post-TKA after 5-day rivaroxaban or enoxaparin lead-in (per AAOS 2025 + EPCAT-II; standard-risk patients only) PO BID for prophylaxis (NOT for symptomatic DVT treatment) (antiplatelet_cox1, first line) — EPCAT-II (Anderson NEJM 2018 PMID 29466159) — ASA 81 mg BID after 5-d rivaroxaban lead-in NON-INFERIOR to continued rivaroxaban for symptomatic VTE prevention after THA/TKA; AAOS 2025 Strong recommendation in standard-risk patients; do NOT use ASA monotherapy in high-risk patients (prior VTE, active cancer, thrombophilia, BMI >40, hip-fracture surgery); never substitute for treatment-dose AC in symptomatic established DVT
4. enoxaparin Treatment: 1 mg/kg SC BID (1 mg/kg daily if CrCl <30); Prophylaxis: 40 mg SC daily (THA/TKA) or 30 mg SC q12h (HFS or extended); 35-d post-THA or 12-d post-TKA SC BID treatment; daily or q12h prophylaxis (lmwh, first line) — ASH 2020 (PMID 33007077); ACCP 2021; AAOS 2025 — LMWH first-line option for high-risk arthroplasty patients and HFS; pre-op LMWH considered if HFS surgery delayed >12 h per HIP-ATTACK (Borges Lancet 2020 PMID 32325025)
5. dabigatran Prophylaxis: 220 mg PO daily after 1-4 h post-op half-dose start × 35 d (THA) or × 10 d (TKA) per RE-NOVATE / RE-MODEL PO daily (doac_direct_thrombin_inhibitor, second line) — RE-NOVATE / RE-MODEL — dabigatran 220 mg daily non-inferior to enoxaparin for prophylaxis; less commonly chosen than apixaban or rivaroxaban; CrCl <30 contraindication
6. warfarin 5 mg daily; INR target 2-3 for treatment of established post-op DVT; for prophylaxis target INR 1.8-2.2 (less commonly used since DOAC era) PO daily (vitamin_k_antagonist, comorbidity specific) — TRAPS (Pengo Blood 2018) — warfarin > rivaroxaban in triple-positive APS; reasonable alternative if DOAC contraindicated; CrCl <15 → warfarin only; mechanical heart valve patients undergoing arthroplasty need warfarin bridge planning
7. heparin 80 U/kg IV bolus + 18 U/kg/h targeting aPTT 1.5-2.5× IV continuous (unfractionated_heparin, comorbidity specific) — Reversibility for acute peri-procedural management; ACCP 2021; reasonable for patients with planned return to OR or active bleed risk requiring rapid AC reversal
8. intermittent pneumatic compression (IPC) Continuous IPC bilateral lower extremities while in hospital (or non-operated leg if surgical-site precludes ipsilateral) mechanical continuous in hospital (mechanical_prophylaxis, add on) — CLOTS-3 (Dennis Lancet 2013 PMID 23484795) — IPC reduces DVT in immobile patients; ACCP 2021 + AAOS 2025 — universal in-hospital adjunct; may serve as primary prophylaxis if pharmacologic AC contraindicated
9. fondaparinux Prophylaxis: 2.5 mg SC daily × 35 d post-THA or × 12 d post-TKA starting 6-8 h post-op (PENTHIFRA / EPHESUS) SC daily (pentasaccharide_factor_xa_inhibitor, second line) — PENTHIFRA / EPHESUS — fondaparinux non-inferior to enoxaparin for arthroplasty prophylaxis; HIT-safe alternative; renal contraindication CrCl <30

Setting playbook (outpatient) — Long-term post-arthroplasty surveillance: AC stopped at 3 mo for symptomatic provoked-by-reversed-substrate DVT; orthopedic prosthesis surveillance; future-surgical-prophylaxis awareness; PTS surveillance; address persistent VTE risk factors
10. STOP AC at 3 mo if substrate reversed (provoked-by-arthroplasty) AC stopped PO n/a — Standard provoked VTE pathway with substrate reversal (ACCP 2021 strong recommendation)
11. EXTENDED low-dose AC if breakthrough on adherent prophylaxis or thrombophilia detected apixaban 2.5 mg BID extended-low-dose; OR rivaroxaban 10 mg daily extended PO BID or daily — Breakthrough VTE on adherent prophylaxis or confirmed thrombophilia (AMPLIFY-EXT (PMID 23216615); EINSTEIN-CHOICE (Weitz NEJM 2017 PMID 28316279))
12. enoxaparin pre-op for future arthroplasty (contralateral or revision) 40 mg SC daily prophylaxis OR 1 mg/kg SC BID treatment if active VTE history SC daily/BID — Future arthroplasty cycle (AAOS 2025 + ACCP 2021 — extended prophylaxis 35 d hip / 12 d knee for any new arthroplasty)

Non-pharmacologic actions:
- Compression stockings 15-30 mmHg below knee for daily use if PTS symptoms
- PT/OT for ongoing mobility maintenance + functional optimization
- OCP discussion: switch to non-oestrogen contraception if recurrent VTE history
- Address modifiable risk factors (obesity, smoking, inactivity)
- Future-surgical-prophylaxis card carried by patient

AVOID / contraindication checks:
- Doac_avoid_active_bleeding (FDA labels)
- Apixaban_avoid_egfr_below_15 (FDA label)
- Rivaroxaban_avoid_egfr_below_30 (FDA label)
- Dabigatran_avoid_egfr_below_30 (FDA label)
- Lmwh_renal_dose_reduction_below_egfr_30 (FDA label)
- Fondaparinux_avoid_egfr_below_30 (FDA label)
- Warfarin_avoid_pregnancy_use_lmwh (ASH 2018)
- Asra_2018_neuraxial_AC_timing_strict (Horlocker 2018) — LMWH 12 h before block; rivaroxaban 22 26 h before block; epidural removal 12 h post LMWH
- Hold_AC_if_post_op_active_bleed_or_haematoma (surgical bleed risk)
- Hit_4ts_screen_if_platelet_drop_above_50_percent_5_to_14d_into_lmwh (ASH 2018)
- Decision:asa_monotherapy_only_for_standard_risk_after_5d_doac_or_lmwh_lead_in (EPCAT II PMID 29466159; AAOS 2025)
- Decision:asa_NOT_for_high_risk_prior_vte_active_cancer_thrombophilia_bmi_above_40_or_HFS (AAOS 2025)
- Decision:extended_prophylaxis_35d_post_THA_or_HFS (ACCP 2021; AAOS 2025; RECORD)
- Decision:extended_prophylaxis_12d_post_TKA (ACCP 2021; AAOS 2025; RECORD 3)
- Decision:DOAC_or_LMWH_required_for_HFS_no_ASA_monotherapy (AAOS 2025)
- Decision:treatment_dose_AC_3mo_for_symptomatic_post_op_DVT (ACCP 2021 provoked VTE rule)
- Decision:asymptomatic_distal_dvt_extended_prophylactic_AC_or_serial_imaging_per_shared_decision (ACCP 2021)
- Decision:thrombophilia_testing_only_if_breakthrough_VTE_on_documented_prophylaxis_adherence_or_other_ASH_2018_indications
- Decision:ipc_universal_in_hospital_adjunct (CLOTS 3 PMID 23484795; AAOS 2025)
- Decision:ipc_primary_prophylaxis_if_pharmacologic_contraindicated (AAOS 2025)

Monitoring

Regimen monitoring:
- cbc at 4 weeks then 3 months during treatment AC (DOAC label monitoring)
- creatinine at 4 weeks then 3 months (DOAC dose adjustment)
- pts villalta at 3 6 12mo (Kahn Lancet 2014)
- symptom recheck at 2 weeks then 3 months (ACCP 2021)
- compression stocking 30 40mmhg if symptomatic pts (ATTRACT subgroup)
- orthopedic followup at 6 weeks for substrate reversibility check (ambulatory at 6 wk = reversed)
- hit 4t score recheck if platelet drop 5 14d into lmwh (ASH 2018)
- inr weekly during warfarin titration then q4-6 weeks (ACCP 2021)
- asra 2018 neuraxial timing documented for each AC dose around catheter removal
- physical therapy engagement documented for mobility restoration

Setting (outpatient) monitoring:
- Annual PCP visit
- Annual orthopedic surveillance
- CBC + creatinine annually if on extended AC

Follow-up plan: STOP AC at 3 mo for provoked-by-reversed-factor presentation per ACCP 2021; 6-wk orthopedic follow-up confirms substrate reversal (ambulatory, prosthesis healed); future arthroplasty (contralateral or revision) requires the same extended-prophylaxis cycle; reinforce future-surgical-prophylaxis awareness; cardiac rehab if HFS in elderly patient
- Close-out criterion: AC stop date + future-surgical-prophylaxis plan documented

Monitoring phase: Symptom resolution at 2 weeks; PTS Villalta at 3/6/12 mo; bleed surveillance during AC; compression stocking 30-40 mmHg if symptomatic for PTS prevention; orthopedic surgeon coordination for prosthesis-site exam; physical therapy reactivation timeline; substrate-reversibility marker (ambulatory at 6 wk for hip; 4-6 wk for knee)

Disposition

Current setting: outpatient — Long-term post-arthroplasty surveillance: AC stopped at 3 mo for symptomatic provoked-by-reversed-substrate DVT; orthopedic prosthesis surveillance; future-surgical-prophylaxis awareness; PTS surveillance; address persistent VTE risk factors

Disposition criteria:
- Standard outpatient PCP + orthopedic follow-up; AC management terminated at 3 mo unless extended indication

Escalation triggers (move to higher acuity):
- New VTE despite prevention plan → restart AC + evaluate for thrombophilia + consider extended-phase AC
- Pregnancy → switch to LMWH per ASH 2018
- Future arthroplasty (contralateral or revision) → extended prophylaxis cycle (35 d hip / 12 d knee)

Earlier-Return Triggers

Return-precaution thresholds (watch for):
- [LIFE_THREATENING] Post-major-orthopedic-surgery patient (THA / TKA / HFS) within 35-day RECORD prophylaxis window develops massive PE with sustained hypotension or cardiac arrest
- [LIFE_THREATENING] Sudden back pain + new lower-extremity neurologic deficit (weakness, sensory loss, urinary retention) in patient with recent neuraxial (spinal/epidural) anaesthesia + recent AC administration — spinal hematoma is a surgical emergency
- [LIFE_THREATENING] Platelet drop >50% from baseline 5-14 days into LMWH prophylaxis with new lower-extremity thrombosis — HIT with HITT (HIT-related thrombosis) confirmed by 4T score ≥6 + serotonin-release assay or anti-PF4 ELISA positive

Citations

- AAOS 2025 VTE Prophylaxis Post-Arthroplasty + ACCP/CHEST 2021 (Stevens) + RECORD program + EPCAT-II + ASRA 2018 neuraxial AC [PMID:34352295](https://pubmed.ncbi.nlm.nih.gov/34352295/)
- Cited evidence (PMID 33007077) [PMID:33007077](https://pubmed.ncbi.nlm.nih.gov/33007077/)
- Cited evidence (PMID 30482764) [PMID:30482764](https://pubmed.ncbi.nlm.nih.gov/30482764/)
- Cited evidence (PMID 18579812) [PMID:18579812](https://pubmed.ncbi.nlm.nih.gov/18579812/)
- Cited evidence (PMID 18582928) [PMID:18582928](https://pubmed.ncbi.nlm.nih.gov/18582928/)

Last reconciled with current guidelines: 2026-05-15.

References

AAOS 2025 VTE Prophylaxis Post-Arthroplasty + ACCP/CHEST 2021 (Stevens) + RECORD program + EPCAT-II + ASRA 2018 neuraxial AC — PMID:34352295
Cited evidence (PMID 33007077) — PMID:33007077
Cited evidence (PMID 30482764) — PMID:30482764
Cited evidence (PMID 18579812) — PMID:18579812
Cited evidence (PMID 18582928) — PMID:18582928