2. OBJECTIVE
⸠What is a D-Dimer (DD)
⸠Introduction / Background
⸠Inclusion / Exclusion criteria
⸠Data Points
⸠Analysis
⸠Discussion / Conclusion
3. WHAT IS A D-DIMER (DD)
⸠D-Dimer (DD) introduced since 1990s
⸠Fibrin degradation product
⸠Small protein fragments in blood post fibrinolysis.
⸠Contains 2 D fragments of fibrin protein cross linked.
⸠Useful in diagnosing a range of thrombotic pathologies.
⸠Particularly useful when negative and used as a exclusion criteria for
thrombosis.
4. INTRODUCTION / BACKGROUND
â¸Recent retrospective audit on aged DD - population pt >50yo
â¸â 500 patients per year had CTPAs
â¸â1/3rd had DD
â¸â2/3rd DID NOT have DD
â¸DD omitted ?due to exclusion criteria such as e.g. symptoms >1/52, etc?
â¸Audit to assess if CTPAs are requested appropriately for PE without DD
â¸Can CTPAs be cut down? (Radiation CTPA = 2-3 years of BG radiation)
â¸53 cases identified with a CTPA but without DD
5. INTRODUCTION / BACKGROUND
â¸Recent retrospective audit on aged DD - population pt >50yo
â¸â 500 patients per year had CTPAs
â¸â1/3rd had DD
â¸â2/3rd DID NOT have DD
â¸DD omitted ?due to exclusion criteria such as e.g. symptoms >1/52, etc?
â¸Audit to assess if CTPAs are requested appropriately for PE without DD
â¸Can CTPAs be cut down? (Radiation CTPA = 2-3 years of BG radiation)
â¸53 cases identified with a CTPA but without DD
6. INCLUSION CRITERIA
â¸Cases with CTPA
and
â¸No D-Dimer beforehand
and
â¸Age >50 yo
⣠None SCGH ED patients
(e.g. KEMH T/F) or IP
⣠Aged <50 yo
⣠CTPA not performed for
acute PE, or for surveillance
of a known acute PE
EXCLUSION
CRITERIA
⣠53 notes were audited, 4 were excluded due to exclusion criteria
7. DATA POINTS
â¸Demographic data
â¸PC - from presentation Code/triage
â¸D/C diagnosis in EDIS / Topas
â¸Ix for DVT/PE (DD, US, VQ, CTPA,MRPA, PA, venogram)
â¸WELLS score (Prospective OR Retrospective)
8. â¸Potential reasons for not performing DD
â¸Delayed symptoms (>1/52)
â¸Pregnant (3rd trimester) or <1/52
postpartum
â¸Recent major trauma <1/52
â¸Invasive surgery <1/52
â¸Current inpatient
â¸Severely unwell / unstable
â¸Active cancer (<6/12 since therapy /
palliative)
â¸Other DVT / VTE / major thrombosis
diagnosed prev 1/52
â¸High pre-test risk of PE
â¸On Warfarin, NOAC, heparin
â¸Reason for not performing a DD documented
â¸Definitive alternative diagnosis documented before discharge home.
9. LIMITATIONS OF AUDIT
â¸Based on documentation / reports
â¸Auditing CTPAs for PE diagnosis
â¸WELLS is subjective
â¸Assumptions:
â¸If calf examination not documented - assumed nil signs of DVT
â¸PE most likely diagnosis - based on clinical history / examination
findings documented / differential diagnosis listed
â¸If no mention of previous DVT,PE / Cancer / Recent immobilisation /
haemoptysis - assumed these were not present
10. DEMOGRAPHICS
â¸Age range 50-88 (so none
were PERC able)
â¸Gender female 27, male 22
â¸Time / date attendance range
08/03/16 - 26/10/16
Fe
ma
lâŚ
Ma
les
4âŚ
13. PRESENTING COMPLAINT
⸠Respiratory Short of Breath 17
⸠Pain â Chest 15
⸠Respiratory Cough 4
⸠Pain â Back 2
⸠Regional Problem âInfection / Inflammation
2
⸠Temperature / Environmental Fever 2
⸠Temperature / Environmental Acopia 1
⸠Cardiovascular / Palpitations 1
⸠Drug / Alcohol Use 1
⸠Neurological â Altered Conscious State 1
⸠Neurological â Syncopal 1
⸠Provisional Diagnosis â ?DVT 1
⸠Urology/Reproductive âurinary retention-
(MS) 1
14. DISPOSITION
â¸Admitted 42
â¸EDU 1 - TOC Ortho (CTPA - No PE)
â¸Obs 2
⸠DC 1 (CTPA - No PE)
⸠TOC Resp 1 (CTPA - No PE, progression
interstitial pneumonitis)
â¸DC from ED by MAU 1 (CTPA - No PE)
â¸Discharged 7
15. DIAGNOSIS EDIS / TOPAS / DC SUMMARY
9
8
4
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0 2 3 5 6 8 9 11
Chest Pain Unknown Cause
PE
Pneumonia
Neoplasia - Respiratory System
Dyspnoea
Acute Cholecystitis
Aspiration Pnuemonia
Bronchitis
Cardiogenic Pulmonary Oedema
Coagulation Defect
Diazepam / Traadol OD
Fall
Generalised Infection
Generally unwell
Haemoptysis
Limb Swelling
Neoplasia - Malignant Mesothelioma
Neoplasia Metastasis to lung
Neutropenia and Febrile
Pleurisy
Shortness of Breath
Syncope not heat
Tachycardia
16. D-DIMER USAGE
â¸No = 49
â¸Yes = 0
â¸DD cancelled in 1 case
and proceeded to CTPA
â¸(No Reason
documented, WELLS 0)
â¸CTPA - No PE
â¸Diagnosed as NSTEMI
(Trop 2640 - 3060)
19. COULD CTPA BE REDUCED?
â¸Of 36 Negative CTPA: WELLS scores range 0-11
⣠3/36 WELLS > 6 (High pre-test probability)
⣠33/36 WELLS <6 (Low / intermediate pre-test probability)
â¸24 had appropriate reasons for not doing a D-Dimer
â¸6 No reason documented
â¸3 PE not on differentials in ED
20. COULD CTPA BE REDUCED?
â¸Of 36 Negative CTPA: WELLS scores range 0-11
⣠3/36 WELLS > 6 (High pre-test probability)
⣠33/36 WELLS <6 (Low / intermediate pre-test probability)
â¸24 had appropriate reasons for not doing a D-Dimer
â¸6 No reason documented
â¸3 PE not on differentials in ED
22. â¸Of 11 Positive CTPA: WELLS range 1-7
â¸1/11 WELLS > 6 (High pre-test probability)
â¸10/11 WELLS <6 (Low / intermediate pre-test probability)
â¸7 had appropriate reasons for not doing a D-Dimer
â¸2 No reason documented
â¸1 PE not on differentials in ED
â¸Of the 2 Suboptimal - Both WELLS of 2.5 + Both had reason for
not doing D-Dimer
COULD CTPA BE REDUCED?
23. â¸Of 11 Positive CTPA: WELLS range 1-7
â¸1/11 WELLS > 6 (High pre-test probability)
â¸10/11 WELLS <6 (Low / intermediate pre-test probability)
â¸7 had appropriate reasons for not doing a D-Dimer
â¸2 No reason documented
â¸1 PE not on differentials in ED
â¸Of the 2 Suboptimal - Both WELLS of 2.5 + Both had reason for
not doing D-Dimer
COULD CTPA BE REDUCED?
25. WELLS CALCULATED / PROSPECTIVE VS
RETROSPECTIVE
Notes
41
PE
Pathway
8
Prospective 9
Retrospective
40
26. REASON FOR NOT DOING D-DIMER
22
2
1
3
5
7
8
4
0 6 12 18 24
Active Cancer / CancerâŚ
Current Thrombosis
Inpatient
On Warfarin / NOAC /âŚ
Prolonged SymptomsâŚ
Invasive Surgery <1/52
No Reason
PE not on differential in ED
⸠No reason - 16% â¸PE not on differential in ED - 8%
27. REASON FOR NOT DOING D-DIMER
22
2
1
3
5
7
8
4
0 6 12 18 24
Active Cancer / CancerâŚ
Current Thrombosis
Inpatient
On Warfarin / NOAC /âŚ
Prolonged SymptomsâŚ
Invasive Surgery <1/52
No Reason
PE not on differential in ED
⸠No reason - 16% â¸PE not on differential in ED - 8%
29. NO REASON DOCUMENTED FOR D-DIMER
Positive:
PE 2
Negative, 6
â¸WELLS score Range 0-4.5
â¸Based on PE Pathway - DD could have been done
30. PE NOT ON ED DIFFERENTIAL
â¸All 4 were organised by admitting team. WELLS range 1.5-4.5
â¸ED differential:
â¸3 No PE on CTPA - Pneumonia / Chest pain unknown / Generalised
infection - PUO
â¸1 CTPA: Right mid lobar + segmental PE, no right heart strain
⸠Acute Choleycystitis (EDIS)
â¸PC - Neurological altered conscious state - noted to be more lethargic, T
40.1, P 120, RR 20, O2 88% RA, BP 120, nauseated (NH Res)
â¸CT Triphasic - diverticulosis, potential Cholecystitis and PE
31. REASON FOR NOT DOING D-DIMER
22
2
1
3
5
7
8
4
0 6 12 18 24
Active Cancer / CancerâŚ
Current Thrombosis
Inpatient
On Warfarin / NOAC /âŚ
Prolonged SymptomsâŚ
Invasive Surgery <1/52
No Reason
PE not on differential in ED
⸠No reason - 16% â¸PE not on differential in ED - 8%
32. REASON FOR NOT PERFORMING D-DIMER
â¸Not documented 42
⣠2 used PE Pathway but left this section blank
⣠1 mentioned D-Dimer Cancelled
⣠Documented 7
⣠6 used PE Pathway
⣠1 mentioned low index of suspicion of PE, but not suitable for D-
Dimer thus exclude PE with CTPA (Active cancer/cancer
treatment) (WELLS 2.5) CTPA - Neg
34. DISCUSSION / CONCLUSION
â¸Majority of PC are Cat 2 + SOB and/or chest pain
â¸Other modality used for Ix is USS
â¸No reason documented for not doing DD 8/49 (16%)
â¸Neg CTPA - 6/33 (18%) - Low/Int for PE - No documented reason for not
doing DD
â¸Pos CTPA - 2/10 (20%) - Low/Int for PE - No documented reason for not
doing DD
â¸Majority of WELLS calculated retrospectively from notes.
â¸Those that used PE pathway - Great compliance to documentation
35. â¸Most common reason for not doing DD was active cancer
â¸Not an exclusion criteria, part of WELLS only
â¸Still some benefit for doing DD
â¸PE was not on differential in ED 4/49 (8%)
36. â¸Most common reason for not doing DD was active cancer
â¸Not an exclusion criteria, part of WELLS only
â¸Still some benefit for doing DD
â¸PE was not on differential in ED 4/49 (8%)
â¸Overall, CTPAs are being ordered appropriately, BUTâŚ
â¸Compliance with PE pathway will improve documentation
and would reduce any unnecessary CTPAs