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Rational approach to evaluate a bleeding patient 2014
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Rational approach to evaluate a bleeding patient
Dr. Thanuja Dissanayake Consultant Haematologist
DGH Chilaw
How does bleeding start and stop?
• Blood vessel injury
• The capillary contracts to help slow
the bleeding (Vascular phase ) • Platelets make a plug to patch the
hole (Platelet phase)
• Clotting factors in plasma work together to form a clot over the plug (Coagulation phase)
• Anticlotting mechanisms are activated to allow remodling of the clot and repair of the damaged vessel (Fibrinolytic phase)
Important to remember • Primary/ congenital bleeding disorders are rare.
• Bleeding due to secondary causes are much common. - Local problems(e.g. polyps, varices, fibroids) - Drugs (e.g.antiplatelets, anticoagulants, antibiotics) - Systemic illnesses(e.g. liver/renal disease, malignancy) - Failed surgical technique - Massive transfusion - Coagulation activation through tissue trauma and or shock, leading to DIC - Procedure-related effects (cardiopulmonary bypass and orthotopic liver transplantation)
• All of the available tests of haemostasis have limitations.
Therefore
• Key to the accurate diagnosis of unexpected bleeding lies on clinical assessment, often requiring a visit to the bedside, rather than reliance on investigations.
Evaluation of a bleeding patient
• Clinically well patient – Out patient
• Ill patient – Hospitalized
• Obtaining a meaningful history – most important, but more difficult than it sounds!!!
↓
• Physical examination
↓
• Appropriate laboratory tests
(Haemostatic screening tests)
Haemostatic history questionnaire
Data collection
Out patients Hospitalized patients
Patient Patient
Parents /Guardians By stander
Family members Family
Nurses
Medical records
Previous / current lab records
Haemostatic history questionnaire
1) Presenting bleeding problem
*Type of bleeding – Spontaneous / Post traumatic - * Site of bleeding
- Skin – Purpura/ Petechiae / Ecchymoses
Petechiae Ecchymoses
► ? Located where trauma is unlikely or unexplained by the severity of injury, e.g. Large bruises after minimal trauma & on the trunk ► Bruises are rare in children < 1 yr ► In active youngsters ecchymotic patches below knee are common ► Simple easy bruising is common in elderly & on long term steroids
- Mucosal
– Epistaxis - ? Chronic or habitual ( Bleeding when coming from cold
→ warm environment ) - Can be normal in children - Repeated nose bleeds lasting more than 10 minutes despite compression suggest a local cause or an underlying bleeding disorder. - Involves both sides - Needs ENT referral to exclude any local cause
– Gum bleeding – Important if there is no gingival disease and
if it is unrelated to the trauma of brushing.
– Menorrhagia – Difficult to assess
- Passage of clots – Retroverted uterus can cause passage of clots due to retention and coming out with change in position (Needs gynae opinion to exclude local causes) - Since menarche / Persistent & sufficient to cause anaemia requiring iron therapy/ transfusions raise the suspicion of a bleeding problem
- Deep tissue bleeding – Muscle – Psoas bleeds can mimic appendicitis
– Joints - Unexplained ‘arthritis’ or joint swelling
- Spontaneous h’ge into synovial joints is highly
suspicious of a coagulation disorder esp. in males (? Haemophilia A/B)
– Life threatening bleeds – - Intracranial - ? Rupture of aneurysm / Vascular
malformation
- Retroperitoneal bleeding – may mimic renal colic
- H’ge in to bowel wall – may mimic intestinal
obstruction
– Haematetmisis/malaena/haematuria/haemoptytsis - Without any explainable cause
2) Past history of bleeding - Prolonged bleeding after trauma or surgery
- ?profuse or intermittent - Extent of bleeding in relation to the degree of trauma - ? Delayed bleeding / poor wound healing – Could be a coagulation disorder - Umbilical stump bleeding – Coagulation factor def. (F XIII def.) - List all the operations & sig. trauma – To assess whether Pt had met with reasonable haemostatic challenges and the ability to withstand them
- Episodes of bleeding - Blood products/ drugs administered / ways & means used to control bleeding & the response
• Tonsillectomy & adenoidectomy – If had no peri-op
excessive bleeding → unlikely to be a bleeder (as it is a very vascular area)
• Circumcision – may be the 1st bleeding manifestation in a muslim child
• NVD & post partum period
• Tooth extractions - Profuse in upper molar - Brisk bleeding for 1 hour - Serous oozing for 2 days
NL occurrence for any
person, not considered
as a bleeder
3) Family history
- Blood relatives with bleeding problems - Immediate & extended family ( Draw a family tree) - Affected members-?Male/female/both (X-linked/ autosomal) - Type of bleeding - ? Similar or not - Diagnosis - ? Known ( Go through the diagnosis cards or previous records and see whether the diagnosis is properly established by investigations) - Hx of bleeding problems in relation to surgery or trauma
4) General health - Evidence of a disorder known to be associated with a
bleeding tendency
- Chronic liver disease - Renal disease - MPD ( ↑ but abnormal Plt ) - Malignancy with liver deposits - Malabsorption - SLE - Leukaemia ( Can be associated with DIC ) - Congenital Ht disease ( Can be associated with vWD) - Myeloma ( Can be associated with acquired vWD )
5) Drug history - Antiplatelet drugs – Aspirin/ NSAID / Garlic
- Anticoagulant therapy – Warfarin / heparin
- Prolonged antibiotic therapy (Affects vit K absorption)
- Change in medication
6) Evidence of abuse
(Suspect when ecchymotic patches in children)
- Ecchymoses of various colours ( Child had been abused
for a long period)
7) Self- inflicted injury - Patches in accessible areas
- Mostly linear & parallel to each other
Physical examination
• Purpura
Palpable purpura → Anaphylactoid purpura / Vasculitis
• Enlarged LN→ Chronic infections / Malignancy
• Splenomegaly → MPD / Malignancy
• Signs of liver decompensation
• Telangiectasia → Osler –Weber – Rendu disease
• Albinism → Hermansky – Pudlak syndrome, MVP, vWD
• Hyperextensible jt & paper-thin scars
→ Ehlers-Danlos syndrome
• Skin plaques & scalloped tongue → Amyloidosis
• Musculoskeletal abnormalities → Haemophilia
Non palpable Petichiae / Ecchymoses (Vascular / Plt / Coag. less common)
• In a hospitalized patient ;
- Whether bleeding seems appropriate for the injury /
surgery
- Single / multiple sites involved
- Wounds / IV sites esp. old IV sites / previous finger or heel prick sites / bleeding time site
- Petichiae in dependent location
- Bruising over the flank ( suggest retroperitoneal h’age)
- Fluid collection bags (urine, gastric, wound drainage, pleural fluid)
Petechiae Spider naevi Telangiectasias
Haemophilic
arthropathy
Anaphylactoid
purpura In HSP
Skin plaques in
amyloidosis
Findings Coagulation disorders
Plt / Vascular dosorders
1. Petechiae Rare Characteristic
2.Deep dissecting haematoma
Characteristic Rare
3.Superficial ecchymoses Large & solitary Characteristic , small & multiple
4.Haemarthrosis Characteristic Rare
5.Delayed bleeding Common Rare
6.Bleeding from cuts Minimal Common
7.Sex Common in males (80-90%)
Common in females
8.Positive F/H Common Rare except vWD
With the information obtained by Hx , Ex & previous lab records
Identify 4 categories of patients a. Definite bleeder b. Questionable, need more tests to decide c. Questionable as haemostatically not fully challenged d. Not a bleeder
• All pts except category ‘d’ should be subjected to the first line screening tests.
First line screening tests
• Full blood count
• Blood picture (EDTA / non- EDTA)
• Skin bleeding time
• Activated Partial Thromboplasin Time (APTT)
• Prothrombin time (PT)
• Thrombin Clotting Time (TCT)
• Fibrinogen
●Interpret the tests in relation to the age &
physiological changes of the pt’s body
EDTA blood film
Non – EDTA blood film
Skin bleeding time (BT)
• Screening test for primary haemostasis (Plt – vessel interaction & haemostatic plug formation) in ambulatory children & adults with an undiagnosed bleeding condition.
• BT is also altered by hematocrit, skin quality and the technique.
• The inter and intraobserver variation amongst the technicians is as high as 20%.
BT cont… • Does not necessarily reflect bleeding from any other
site1.
• Limited usefulness in invasive procedures2
- In the absence of a Hx of a bleeding disorder, BT is not a
useful predictor of the risk of haemorrhage associated with invasive procedures.
- A normal BT doesn’t exclude the possibility of excessive haemorrage associated with invasive procedure.
- Cannot reliably identify pts who may have recently ingested aspirin/ NSAID or those who have plt defects attributable to these drugs.
1Guideline on the assessment of bleeding risk prior to surgery or invasive procedures ,BCSH, 2007 2Screening tests of haemostasis –Disorders of haemostasis & thrombosis by Hathaway WE, Goodnight SH– 2nd edition
• APTT
- Sensitive to coagulation abnormalities of the ‘intrinsic’
pathway (Factors XII, XI, IX , VIII, V & X)
- Less sensitive to deficiencies of prothrombin (II)
& fibrinogen
• PT
- Sensitive to coagulation abnormalities of the
‘extrinsic’pathway (Factors VII, X, V & II) - Usually not prolonged by low fibrinogen unless the
level is <100mg/dl
• TCT
- Measures the amount and quality of fibrinogen
& the rate of conversion of fibrinogen to fibrin
• Fibrinogen
- 2 assay methods – Quantitative / Qualitative
- Normal adult levels ranges from 175 – 400mg/dl
- Minimal level for normal haemostasis is approximately
75-100mg/dl
- Commonly used screening tests (PT, APTT, TCT) usually
are not prolonged until the fibrinogen level falls <100mg/dl
Capillary tube clotting time (CT)
• Very much out dated test.
• Used in past (when PT/APTT were not available) to assess both the intrinsic and extrinsic pathways of coagulation.
• Getting deranged only when there is a drop in coagulation factor of more than 40% of normal values. (Not sensitive)
• Not carried out at 37°C (NL human temperature)
• No clear cut end point. The test is commonly
misinterpreted because only the initial traces of
thrombin formed is enough to cause the clotting in the outermost part of column of blood within the capillary tube.
• Loss of considerable amount of man-hours per day to the hospital laboratory carrying out the (BT) & CT
PLEASE DON’T
REQUEST FOR CLOTTING TIME (CT) WHEN PT/APTT ARE
AVAILABLE
Abnormal screening tests in various bleeding disorders
Disorder ↓ Plt ↑ BT ↑ APTT ↑ PT ↑ TCT ↓ Fib
1.Thrombocytopaenia X
2.Plt dysfunction X
3.Haemophilia X
4.Early Liver dis./ FVII def.
X
5.Dysfibrinogenaemia (mild)
X
6.Hypofibrinogenaemia (mild)
X
7.Advanced liver dis. X X X X X X
8.Advanced renal dis. X X X X X X
9.DIC X X X X X X
• If all the first line screening tests are normal ↓
No further investigations are necessary
Except in
• Positive family history
• Definite/ significant bleeding history with
normal first line tests
• Definite bleeding history with negative haemostatic screening results can occur
- Mild haemophilia - Mild vWD - F XIII deficiency - Vascular defects - α2 antiplasmin deficiency - Plasminogen activator inhibitor – 1 deficiency
2nd line coagulation tests
• Selection criteria 1. Abnormal 1st line screening test 2. Significant bleeding Hx with normal 1st line tests 3. Positive F/H with normal 1st line tests
• Type of the 2nd line test/s are decided by; 1. Abnormality detected in 1st line test/s 2. Nature of bleeding in patient /family
2nd line screening tests
1. Low platelets - Liver function tests
- Bone marrow – if clinically indicated
2. Near NL plt count /abnormal plt morphology - Platelet function tests
3. ↑ BT - Platelet function tests - von willbrand antigen level - Ricof activity - Multimer analysis
4. Prolonged APTT - Mixing and correction studies - Factor assay - Inhibitor screening - Exclude heparin effect
5. Prolonged PT - Mixing and correction studies - Factor assay - Liver function tests
6. Prolonged TT - Mixing tests - Toludine blue test
7. ↑ BT, APTT, PT, TT with low platelets - D-Dimer - FDP
8. ↑ BT, APTT, PT, TT with normal platelets - Clauss test (Dysfibrinogenaemia)
9. Normal BT, APTT, PT, TT, platelets, fibrinogen - Factor XIII assay / clot solubility test
Pre operative haemostatic evaluation
• Routine /indiscriminate pre-operative performance of bleeding screening tests (BT /APTT/ PT) has not demonstrated to be significantly predictive of haemorrhagic complications or cost effective.
• A screening coagulation profile is not a substitute for the history and physical examination.
• Basic screening lab tests (FBC/ PT/APTT) are reserved/ selected depending on: a) Nature of the patient
1. With positive assessment
2. Who are at higher risk of bleeding because of
special circumstances e.g - Children (<13 yrs) even without any bleeding Hx (Not met with a major haemostatic challenge) - Liver disease
b) Nature and site of Sx
e.g Major Sx at a very vascular/critical site
c) Mode of anaethesia
e.g- For GA – Plt >50,000/µl
For spinal/ epidural – Plt > 80,000/µl
Refrain from transfusion of blood
products unnecessarily to normalize clotting profiles in pts with no bleeding and no plans for invasive procedures!!!
e.g 1. Haemophilia patients -↑↑APTT
2. Chronic liver cell disease Pts -↑↑PT, ↓Plt
3. Burn patients - ↑PT, ↑APTT, ↓Plt
4. DIC - ↑PT, ↑APTT, ↓Plt
5. High INR
Take home message
• Obtain a meaningful history
↓
• Physical examination
↓
• Appropriate laboratory tests
(Haemostatic screening tests)
PLEASE DON’T REQUEST FOR
CLOTTING TIME (CT) WHEN PT/APTT ARE
AVAILABLE
Thank You !