This lecture was conducted during the Nephrology Unit Grand Ground by Medical Student rotated under Nephrology Division under the supervision and administration of Prof. Jamal Al Wakeel, Head of Nephrology Unit, Department of Medicine and Dr. Abdulkareem Al Suwaida. Nephrology Division is not responsible for the content of the presentation for it is intended for learning and /or education purpose only.

Deep Venous Thrombosis Salman Alarfaj Medical Student

Introduction Etiology Risk factors Symptoms & signs Investigations Complications Treatment

Definition: deep vein thrombosis is the formation of a blood clot ("thrombus") in a deep vein.

Deep vein thrombosis commonly affects the leg veins (such as the femoral vein or the popliteal vein ) or the deep veins of the pelvis. Occasionally the veins of the arm are affected (if spontaneous, this is known as Paget- Schrötter disease)Paget- Schrötter disease The blood clot or part of it can break free (called embolism) and become lodged in the blood vessels of the lung, causing pulmonary embolism (PE)

etiology 3main factors contribute in development of DVT : Stasis. Endothelial injury. Hypercoagulability. Theses are VIRCHOW'S TRIAD

Stasis: mainly caused by heart failure, prolonged immobility Endothelial injury: mainly caused by either direct trauma (severed vein) or local irritation (by chemotherapy, past DVT, phlebitis) Hypercoagulability: inherited (AT III def., protein C, S deficiency) or acquired (malignancy, pregnancy, AT III def., protein C, S deficiency as in nephritic syndrome, DIC and liver failure.

Risk factors Illness or injury that causes prolonged immobility increases the risk of a DVT Age >40 years (VTE risk increases with advancing age) Birth control pills and hormone replacement therapy Cancer and its treatment Major surgery (example: abdomen, pelvis, or hip or knee replacement) Obesity Previous DVT or PE A family history of blood clots 7 Certain heart problems Varicose veins

The more risk factors a person has, the greater the chances may be of developing DVT

Pretest clinical probability scoring for DVT : Wells score scoreClinical features 1 pointActive cancer(treatment within 6 months or palliative a) 1 pointParalysis, paresis, or recent plaster immobilization of leg 1 pointMajor surgery or recently bedridden for more than 3 days in last 4 wks 1 pointLocal tenderness along distribution of deep venous system 1 pointEntire leg swollen 1 pointCalf swelling more than 3 cm compared to asymptomatic leg (measured 10cm below tibial tuberosity ) 1 pointPitting oedema (greater in the symptomatic leg ) 1 pointCollateral superficial veins (non varicose ) -2 pointAlternative diagnosis as likely more than that of DVT

Wells score : If more than or equals to 3 : high pretest probability – treat as suspected DVT and perform compression US 1-2 points : intermediate pretest probability – treat as suspected DVT and perform compression US If less than or equals 0 – low pretest probability of DVT : Perform D-dimer test : -if +ve then treat as suspected DVT and perform compression US -if –ve, DVT reliably excluded

symptoms Dull pain, heaviness, oedema and warm limb With extensive DVT:-massive oedema, cyanosis, dilated superficial collateral veins and low grade fever. With ilio-femoral DVT:- Phlegmasia cerulea dolens (cyanosed limb due to obstructed vein) Phlegmasia alba dolens (pale, pulseless cold limb due to concurrent arterial spasm) AND THESE TWO UPPER CASES ARE LIMB THREATENING CONDITION!!

signs HOMAN'S sign (tenderness during passive dorsiflexion of foot). And it was contraindicated because of it ’ s role in thrombus deattachment and thus emobilization Hotness, cyanosis, oedema (non-pitting)

investigations CBC for any abnormalities in Hb, WBC, and platelet count PT aPTT

This cross-linked fibrin degradation product is an indication that thrombosis is occurring, and that the blood clot is being dissolved by plasmin. A low D-dimer level should prompt other possible diagnoses (such as a ruptured Baker's cyst, if the patient is at sufficiently low clinical probability of DVT.fibrin degradation productthrombosisblood clotplasminBaker's cyst D-Dimer: too unspecific

Imaging studies The standard tool for diagnosis is phlebography using fluoroscope.the use of this study limited by is complications which are allergy, nephropathy and phlebitis. *Duplex ultrasound: Test of choice Sensitivity and specificity >95% Include both B mode and Doppler studies. Able to detect other pathology like BAKER cyst.

The findings are : Acute DVT: -Absence of spontaneous flow. -Loss of flow variation with respiration. -Failure to increase the flow after distal augmentation. -Not visible thrombi (anechoic thrombi). Chronic DVT: - Not well established - Narrow vein - Patent collateral - Visible thrombi

MRV (magnetic resonance venography):- Is promising tool for diagnosis, 100%sensitivity, 96% specificity

Differential diagnosis Unilateral limb involvement: muscular strain, tendon rupture, cellulites, lymphodema or retroperitoneal fibrosis pressing over the vein. Bilateral limb involvement: liver, heart or renal failure or IVC obstruction

Complications of DVT Recurrent DVT Varicose vein Chronic venous insufficiency Post phlebitic syndrome (pain, oedema and ulceration) PE

hospitalization should be considered in patients with more than two of the following risk factors as these patients may have more risk of complications during treatment: 1- bilateral DVT 2- renal insufficiency 3- body weight >70 kg/154 lbs 4- recent immobility 5- chronic heart failure 6- cancer

Therapy : Anticoagulants. Thrombolysis. Compression stockings. Inferior vena cava filter

Anticoagulations : - Anticoagulation is the usual treatment for DVT. - In general, patients are initiated on a brief course (i.e., less than a week) of heparin treatment while they start on a 3- to 6-month course of warfarin (or related vitamin K inhibitors).heparinwarfarinvitamin K - Low molecular weight heparin- Low molecular weight heparin (LMWH) is preferred,though unfractionated heparin is given in patients who have a contraindication to LMWH (e.g., renal failure or imminent need for invasive procedure).heparin - In patients who have had recurrent DVTs (two or more), anticoagulation is generally "life-long."

Thrombolysis : - is generally reserved for extensive clot, e.g. an iliofemoral thrombosis. - Although randomized controlled trials shows improved outcomes with thrombolysis, there may be an increase in serious bleeding complications.randomized controlled trials thrombolysis

Compression stocking : Elastic compression stockings should be routinely applied "beginning within 1 month of diagnosis of proximal DVT and continuing for a minimum of 1 year after diagnosis".compression stockings Starting within one week may be more effective. randomized controlled trials showed reduced incidence of post-phlebitic syndrome. [randomized controlled trials

Inferior vena cava filter : reduces pulmonary embolism, and is an option for patients with an absolute contraindiciation to anticoagulant treatment (e.g., cerebral hemorrhage) or those rare patients who have objectively documented recurrent PEs while on anticoagulation. An inferior vena cava filter (also referred to as a Greenfield filter) may prevent pulmonary embolisation of the leg clot.inferior vena cava filterGreenfield filter

Prognosis : Post-phlebitic syndrome occurs in 15% of patients with deep vein thrombosis (DVT). Post-phlebitic syndrome It presents with leg oedema, pain, nocturnal cramping, venous claudication, skin pigmentation, dermatitis and ulceration (usually on the medial aspect of the lower leg) ulceration

Prevention General medical inpatients the guidelines state, "In acutely ill medical patients who have : - been admitted to the hospital with congestive heart failure or severe respiratory disease - who are confined to bed and have one or more additional risk factors, including active cancer, previous VTE, sepsis,acute neurologic disease, or inflammatory bowel disease, we recommend prophylaxis with low-dose unfractionated heparin-LDUH (Grade 1A) or LMWH (Grade 1A) [. - Enoxaparin or unfractionated heparin may be used. - LMWH may be more effective than UFH. If UFH heparin is used, 5000 U 3 times daily may be more effective.

Surgery patients In patients who have undergone surgery, low molecular weight heparins (LMWH) are routinely administered to prevent thrombosis. LMWH can only currently be administered subcutaneously by injectionsurgery low molecular weight heparins

Travellers : There is clinical evidence to suggest that wearing compression socks or compression tights while travelling also reduces the incidence of thrombosis in people on long haul flights. compression tights

summary DVT is a blood clot that forms in a vein deep in the body The clot or part of it may break off and travel to the lung Many conditions may increase your risk for deep vein clots The more risk factors a person has, the greater the chances may be of developing DVT Not all people with DVT have symptoms The main goals in treating DVT are to stop the clot from getting bigger, to decrease your chance of having another clot, and to stop the clot from breaking off in your vein and moving to your lungs

Thank you …