Term
| Deep Vein Thrombosis (DVT) |
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Definition
| thrombus (collection of platelets, RBCs, WBCs bound together w/ fibrin strands) in venous portion of vasculature (most commonly in lower extremities) but can involve ANY vein; |
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Term
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Definition
portion of thrombus that breaks off & lodges in pulmonary artery or one of its branches;
Consequence: complete or partial obstruction of pulmonary blood flow |
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Term
| Primary Components that may cause development of thrombus |
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Definition
1) increased activity of coagulation process (Hypercoaguable State - i.e. malignancy);
2) activation of coagulation process due to endothelial activation by cytokines & exposure of collagen (Endothelial Injury - i.e. atherosclerosis);
3) Increased local concentration of clotting factors --> hypoxia that leads to endothelial damage (Circulatory Stasis - i.e. immobilization after surgery, traveling) |
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Term
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Definition
Factor Xa converts Prothrombin to Thrombin;
Thrombin converts fibrinogen to fibrin; |
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Term
| Clinical Presentation of DVT |
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Definition
Subjective: pain/tenderness in SOME pts - others may be asymptomatic;
Objective:
swelling, warmth, and/or redness/discoloration of extremity, palpation of a cord, positive Homan's sign: pain upon acute dorsiflexion, Lab test: D-dimer evaluation; |
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Term
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Definition
Duplex Ultrasound/Doppler ultrasound: tests for venous flow patterns;
absence of sound = partial or full obstruction of venous flow;
more difficult to detect flow in obese pts;
Venography: GOLD STANDARD - invasive, not usually performed;
uses radiocontrast dye injected into dorsal foot vein or femoral vein & images are taken |
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Term
| Clinical Presentation of Pulmonary Embolism (PE) |
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Definition
Subjective:
dyspnea/SOB, cough, hemoptysis, dizziness/lightheadedness, fealings of anxiety, chest pains;
Objective Findings:
tachypnea >20 rpm, tachycardia >100 bpm, fever, altered mental status, cyanosis, diaphoresis, syncope/shock, decreased O2 saturation, Lab test: D-dimer evaluation; |
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Term
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Definition
ECG changes: ST/T changes --> right heart strain;
CXR: nonspecific --> rules out pneumonia;
ABG: check arterial blood gas;
Spiral CT: detects emboli in pulmonary arteries;
V/Q Scan: radiolabeled albumin injected and radiolabeled gas inhaled, looks for venilation/perfusion mismatch --> detects areas being ventilated but not perfused; results reported in probabilities --> high probability suspect if PE likely;
Pulmonary Arteriogram:
- GOLD STANDARD but invasive - not routinely done |
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Term
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Definition
reflects alterations in extrinsic & common pathways;
Normal: 11 sec
-varies on reagent used |
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Term
| International Normalized Ratio (INR) |
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Definition
used to assess response to WARFARIN therapy;
"standard" way of interpreting PT;
Normal: 0.8 - 1.2
DVT/PE Goal: 2 - 3 |
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Term
| Activated Partial Thromboplastin Time (aPTT) |
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Definition
used to assess response to HEPARIN therapy, but NOT to LMWH;
measures intrinsic & common pathways;
Normal: 24-36 sec, varies by institution |
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Term
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Definition
| products that prevent clot formation & extension (warfarin, heparin, LMWH, fondaparinux) |
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Term
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Definition
| interfere with platelet activity (aspirin, clopidogrel) |
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Term
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Definition
| dissolve existing thrombi (t-PA, alteplase, reteplase, tenecteplase) |
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Term
| Pharmacotherapy of DVT/PE |
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Definition
1) Injectable Therapy: Start drug that will ACUTELY prevent clot from getting bigger:
- Start LMWH or UFH or Factor Xa inhibitor or alternative on day 1
- continue agent for at LEAST 5 days & until warfarin is therapeutic (INR = 2-3) for 2 consecutive days
- continue LMWH monotherapy for 3-6 months if pt has cancer BEFORE transitioning to warfarin;
2) Oral Therapy: Simultaneously start warfarin (day 1), goal INR = 2-3 |
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Term
| Unfractionated Heparin (UFH) |
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Definition
MoA: inhibits Xa/IIa(thrombin) in a 1:1 ratio;
Give IV or SC;
Weight-based Dosing:
80 units/kg IV bolus - MAX = 10,000 units
Followed by INFUSION:
- 18 units/kg/hr, MAX = 2,300 units/hr;
Use ACTUAL BODY WEIGHT!!!
Monitoring:
- check aPTT 6 hrs AFTER start of infusion & adjust PRN by nomogram;
- ALWAYS wait 6 hrs to check aPTT;
- During 1st 24 hrs, check aPTT q6hr;
- If therapeutic at 24 hrs, monitor q24 hrs unless outside therapeutic range |
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Term
| Monitoring Parameters for UFH |
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Definition
Baseline:
- aPTT, PT
- CBC (Hb, Hct, platelets)
- UA, Stool guaiac
At 6 hrs after start of infusion:
- aPTT
Daily:
- aPTT (goal 1.5-2.3 x control)
Ongoing - Signs of bleeding:
- bleeding from IV site, hematoma, bruising, nosebleed (epistaxis), gingival bleeding, hematuria, melena (black, tarry blood in stool), BRBPR (bright red blood per rectum);
Every 1-3 days:
- CBC (Hb, Hct, platelets) |
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Term
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Definition
Hemorrhage:
- minor bleeding: epistaxis, gingival bleeding, ecchymosis, hematuria;
- major bleeding: 2 g drop in Hb requiring bllod transfusion;
Thrombocytopenia;
Osteoporosis (high doses, long duration) |
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Term
| Increased risk of Hemorrhage on UFH |
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Definition
| higher dose, duration; concurrent meds (aspirin, heavy alcohol use); comorbid conditions (GI bleed, PUD); hemostatic defects (uremia, thrombocytopenia, liver dx); recent surgery; age (older), gender (women > men) |
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Term
| Management of UFH for Hemorrhage |
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Definition
depending on severity, decrease dose OR hold dose;
reverse w/ PROTAMINE SULFATE via SLOW IV PUSH |
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Term
| Low Molecular Weight Heparin (LMWH) - enoxaparin (Lovenox), dalteparin (Fragmin) |
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Definition
portions of heparin w/ smaller molecular weight to creat more uniform molecular weight;
MoA: complexes w/ antithrombin III (ATIII), but preferentially inhibits Xa (greater Xa/IIa ratio - 3:1, 4:1);
DO NOT monitor w/ PT or aPTT; |
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Term
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Definition
LMWH for tx of VTE;
Dosing:
1 mg/kg SC q12hrs
1.5 mg/kg SC q24 hrs
Renal Impairment (CrCl<30 ml/min): 1 mg/kg SC q24hrs; |
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Term
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Definition
LMWH for tx of DVT
Dosing:
100-120 units/kg SC q12hr
200 units/kg SC q24hr |
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Term
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Definition
hemorrhage: major bleeding - D/C LMWH, give protamine if needed;
thrombocytopenia (less than UFH);
hypersensitivity (skin necrosis at injection site);
C/I's: DO NOT USE in pts w/ epidural/spinal anesthesia or spinal puncture --> risk of epidural hematoma; |
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Term
| Monitoring Parameters for LMWH, fondaparinux (Arixtra) |
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Definition
Baselin:
- aPTT, PT
- CBC (Hb, Hct, platelets)
- UA, stool guiac, renal fcn
Ongoing - monitor for signs of bleeding:
- bleeding, hematomas, ecchymosis (bruising), epistaxis, gingival bleeding, hematuria, melena, BRBPR
Every 1-3 days:
- CBC (Hb, Hct, platelets) |
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Term
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Definition
1) wash hands w/ soap, dry hands
2) Sit or lie in comfortable position and be able to see stomach;
3) Select area on left or right side of stomach, at least 2 in. from belly button & out toward your sides;
4) clean area with alcohol swabs;
5) Carefully pull needle cap from syringe & discard cap;
6) Hold syringe in hand like pen, gently pinch cleansed area b/w thumb & forefinger, BE SURE TO HOLD SKIN FOLD THROUGHOUT INJECTION;
7) Vertically insert full length of needle into skin fold;
8) Press down on plunger; Hold skin throughout injection;
9) Remove needle by pulling it straight out, let go of skin fold, TO AVOID BRUISING --> do not rub injection site after completeion;
10) Dispose of syringe in red sharps bin |
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Term
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Definition
MoA: antithrombin III-mediated inhibition of Factor Xa;
FDA-approved for DVT/PE treatment;
Dosing is based on ACTUAL BODY WEIGHT;
Administered SC;
C/I if CrCl <30 ml/min due to bleeding risk;
May be useful for treating pts w/ HIT; |
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Term
| Duration of Therapy for Oral Anticoagulant for VTE 2ndary to transient (reversible) risk factor |
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Definition
| Duration for at least 3 months |
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Term
| Duration of Therapy of Oral Anticoagulation (warfarin) for 1st-event unprovoked VTE |
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Definition
| at least 3 months, then evaluate for risk-benefit ratio of long-term therapy, especially if proximal DVT; 3-months sufficient in distal DVT |
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Term
| Duration of Therapy for Oral Anticoagulants (warfarin) for VTE and cancer |
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Definition
| long-term therapy: 1st, LMWH for 3-6 months, then warfarin indefinitely or until cancer is resolved; |
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Term
| Duration of therapy of oral anticoagulant (warfarin) for Recurrent VTE |
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Definition
| long-term therapy: lifetime, unless C/I |
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Term
| Duration of Therapy of Oral Anticoagulants (warfarin) for VTE & hypercoagulable state |
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Definition
| Long-term therapy: lifetime, unless contraindicated |
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Term
| Low-intensity warfarin therapy (INR goal 1.5-2) |
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Definition
| after 3 months of moderate-intensity (INR goal 2-3) anticoagulation, this therapy is preferred over no treatment if pt has a strong preference for less frequent monitoring |
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Term
| When prophylaxis for VTE is Warranted |
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Definition
Pt at risk for VTE;
Evaluate all med & surgical pts;
Medical Pts: ICU, prolonged bed rest, oncology;
Surgical Pts: prolonged procedures, long recovery periods, hip/knee replacement requires it in ALL pts |
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Term
| Nonpharmacological Tx of VTE |
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Definition
Good option when risk is low-moderate;
1) Ambulation
2) Graduated Compression Stockings (GCS)
3) Intermittent Pneumatic Compression (IPC) or Venous Foot Pump (VFP) or Sequential Compression Devices (SCD);
4) Inferior vena cava interruption |
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Term
| Prophylaxis Doses for VTE - enoxaparin (Lovenox) |
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Definition
Indication: hip replacement, knee replacement;
Dose: 30 mg SC q12 hrs
Renal Impaired (CrCl <30 ml/min): 30 mg SC daily;
Indication: abdominal surgery, medical prophylaxis, hip replacement;
Dose:
40 mg SC daily
Renal Dosing: 30 mg SC daily |
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Term
| Prophylaxis Dose of VTE - dalteparin (Fragmin) |
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Definition
Indication: abdominal surgery
Dose: High risk - 5,000 units SC daily;
Low/moderate risk - 2,500 units SC daily;
Indication: Hip Replacement
Dose: 5,000 units SC daily |
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Term
| Options for Prophylaxis in Lower Risk Pts - minor surgeries in mobile pts, medical pts sick or on bed rest |
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Definition
| early & "aggressive" ambulation |
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Term
| Options for Prophylaxis for Moderate-High Risk Pts - most general surgery, medical pts sick or on bed rest |
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Definition
LDUH (5000 units q8-12hrs);
LMWH;
fondaparinux (Arixtra) |
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Term
| Options for Prophylaxis for Highest Risk Pts - hip/knee replacement, hip fracture surgery, major trauma |
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Definition
LMWH;
fondaparinux (Arixtra);
warfarin (goal INR 2-3) |
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Term
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Definition
MoA: inhibits synthesis of vit. K-dependent clotting factors (Factors II, VII, IX, X, Protein C & Protein S);
Half-life: 36 hrs;
Steady-state: 7-10 days, longer in elderly & renal dysfunction;
Highly protein bound;
Monitor using INR; |
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Term
| Warfarin doses for pts <65 yrs old |
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Definition
5-10 mg PO on days 1-2;
consider lower starting doses of <=5 mg if HF, renal insufficiency, concurrent use of interacting meds, liver dx, & high bleeding risk; |
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Term
| warfarin doses for pts > 65 yr old |
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Definition
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Term
| Monitoring Oral Anticoagulation |
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Definition
Monitor q7-14 days when INR is NOT within therapeutic range;
5-20% dosage change for pts OUTSIDE therapeutic range, generally only 5-10% dosage changes needed;
- patient-specific, consider holding 1-2 doses if SUPRAtherapeutic INR;
Try to use only 1 tablet strength; |
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Term
| When to re-check INR after dosing change on pts w/ CHRONIC THERAPY |
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Definition
If SUPRAtherapeutic, recheck after a hold prior to reinitiating;
After 1 INR within range, recheck in 2 wks;
After 2 INR in range, INR should be checked in 4 wks; |
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Term
| Other Monitoring Parameters for warfarin |
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Definition
Monitor CBC baseline & yearly;
Monitor CBC if signs of bleeding |
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Term
| Adverse Effects of Warfarin |
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Definition
bleeding & bruising;
skin necrosis (RARE - occurs in 1st 1-2 wks, increased if "loading dose" given);
Purple toe syndrome (VERY RARE - d/c therapy) |
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Term
| Patient Education for warfarin (Coumadin) |
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Definition
1) signs of bleeding/thromboembolism;
2) CONSISTENCY w/ foods that have Vit. K;
3) Importance of lab monitoring & follow-up;
4) Avoid OTC/Rx products w/ ASA, NSAIDs, cimetidine, herbals;
5) Avoid alcohol;
6) NO MISSED DOSES & no self-changing of dosing regimen;
7) Contraception required in women of child-bearing age;
8) Inform ALL HCPs
9) Medic-alert |
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Term
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Definition
| quinolones (cipro-, norflo-, ofloxacin); metronidazole; TMP-SMX (Bactrim); macrolides (NOT azithromycin); amiodarone; cimetidine; fenofibrate; APAP (>2 g/day); celcoxib (less risk); herbals (ginkgo, garlic, ginseng); antifungals (itra-, keto-, fluconazole); NSAIDs; thyroid hormone (Synthroid) |
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Term
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Definition
vit. K in drugs (MVIs) or diet;
cholestyramine (Questran); rifampin; barbiturates; nutritional supplements |
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Term
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Definition
| decrease dose of warfarin by 25-50% & recheck INR weekly for at least 6 wks; |
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Term
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Definition
| Monitor INR weekly; will probably have to increase warfarnin when stopping this agent |
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Term
| INR therapeutic but <5 & no signs of bleeding |
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Definition
- no vit. K indicated;
- decreases warfarin dose and/or omit 1 dose;
- if only minimally above therapeutic range, no dose reduction may be required; |
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Term
| INR > or = 5 but <9 & no significant signs of bleeding |
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Definition
- if minimal risk for bleeding: omit 1-2 doses, resume warfarin at lower dose when INR therapeutic;
- if increased risk for bleeding: omit 1-2 doses & resume warfarin at lower dose when INR in therapeutic range; alternatively, vit. K 1-2.5 mg PO & resume warfarin at lower dose when INR is in therapeutic range;
- if rapid reversal required for surgery: vit. K < or = 5 mg PO, may repeat w/ 1-2 mg vit. K if needed |
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Term
| INR > or = 9 & no signs of significant bleeding |
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Definition
- hold warfarin & give vit. K 2.5-5 mg PO;
- repeat in 24-48 hrs if INR NOT substantially reduced |
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Term
| Serious Bleeding or Life-Threatening Bleeding |
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Definition
| - hold warfarin & give vit. K (10 mg by slow IV infusion) supplemented w/ fresh plasma, prothrombin concentrate, or recombinant Factor VIIa |
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Term
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Definition
| effective, monitoring, oral |
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Term
| Disadvantages of warfarin |
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Definition
narrow therapeutic index;
monitoring;
drug & dietary interactions;
onset of effect (7-10 days) |
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Term
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Definition
drug on horizon;
direct thrombin (IIa) inhibitor;
Oral, once daily;
converted from prodrug --> liver; 80% reanlly cleared;
Bioavailability: 7.2%;
Drug Interactions: verapamil, quinidine |
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Term
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Definition
direct Factor Xa inhibitor;
Administer orally, daily-BID;
66% renally cleared;
Bioavailability - 80% |
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