- Full dose(treatment for DVT)
- IV ADMINISTRATION-get baseline PTT-5,000-10,000u IV bolus, then 750-1,500u/hr IV-monitor PTT q8h (maintain PTT at 1.5-2 above control)
- SubQ ADMINISTRATION-get baseline PTT-5,000u IV bolus and 10,000-20,OOOu subQ, then 8,000-10,OOOusubQ q8h or 15,000-20,OOOu subQ BID-monitor PTT q8h(maintain PTT at 1.5-2 above control)
- Mini dose(prophylaxis for DVT)-5,OOOu subQ bid-surgical patients-give 1 hour pre-op followed by bid dose until ambulatory
- Warfarin(Coumadin, Panwarfin)loading dose 10mg PO qd x2-4 daysmaintenance dose 2-7.5mg PO qdmaintain PT about 2-2.5 times normaltreat 1st DVT episode for 3 months-Coumadin requires 16-48hrs to cause a measurable change in the PT,therefore begin Tx 2 days before discontinuing Heparin
- DEEP VENOUS THROMBOSIS(DVT)
- DESCRIPTION Partial or complete occlusion of a vein by thrombus with secondary inflammatory reaction in the wall of the vein. Arises approximately 80% of the time in the deep veins of the calf. Contributing factors include those of Virchow's Triad such as: CHF, MI, stroke,malignancy, Sx, trauma, immobilization, previous thromboembolic dz, obesity, pregnancy, oral contraceptives, and advanced age. The typical patient is a woman over 30 yrs old, on BCP's who smokes. There is a danger of pulmonary embolism in these patients. DVT usually results in destruction of the venous valves resulting in veins that are incompetent resulting in postphlebitic syndrome(venous insufficiency).
- SIGNS/SYMPTOMS-Symptoms arise over a period of hours to 1-2 days.-Self limiting and lasts 1-2 weeks-Distention of superficial venous collaterals, and slight fever and tachycardia may develop.-Physical exam is normal in 50% of pts-Painful swollen leg with dilated superficial veins and a palpable cord-(+) Homan's sign-dorsiflexion of foot causes deep pain in calf-Pulses are usually present
- DIAGNOSIS-Difficult to diagnose by Hx and PE-Venography remains the gold standard
- TREATMENT-Leg should be elevated -15-20°, trunk should be kept horizontal-Bedrest until local tenderness and swelling disappears-Heparin(bolus of 5,000-10,000 units IV followed by a continuous IV infusion of 500 units/kg every 24hrs).-PTT should be checked 4-6hrs after initial therapy and then at least every 24hrs. PTT levels should be maintained at 2-3 times the control value-Monitor ABGs-Pt should later be started on long term anticoags(Coumadin) loading dose of 10mg is given each day until PT increases.Then a smaller dose (5-7.5mg) is given to maintain PT ~1.3-1.5 above the control value. Pts should be Tx for 3 months for the 1st episode.
Antiembolism stockings 16-18mmHg DVT prophylaxis
72 hours or greater-infection(3-7 days)-DVT-thrombophlebitis from IV-UTI(especially if catheterized)-drug allergy
Five "W"s(mnemonic for remembering cause of post-op fever)Wind-atelectasis. aspiration pneumonia, PEWound-infection. thrombophlebitis(IV site), painWater-UTI. dehydration, constipationWalking-DVT
Wonder drugs- virtually any drug can cause fever(pt appears less illthan fever suggests)
DVTSurgical patients have additional risk factors for DVT's-bed rest-tourniquet-surgical trauma-infection-dehydration(due to NPO status)-change in medication(ie d/cASA)
Lower extremity deep vein thrombophlebitis (DVT, also known as venous thromboembolism,or VTE) presents with deep, aching pain and tightness in the calf or thigh. Pain upon active dorsiflexion of the ankle, or resistance to ankle dorsiflexion is known as Homan's sign, andis a nonspecific and unreliable clinical diagnostic maneuver. Tenderness upon calf or thigh muscle compression is a more specific test for DVT, when associated with edema and local increase in skin temperature. Superficial thrombophlebitis, which conveys a lower likelihood of PE, more commonly displays local heat, edema, erythema, and a palpable cord consistent with the thrombosed vein. Application of a tourniquet above the suspectedthrombosis may cause pain atthe level ofthrombosis within 30-45 seconds, and is stronglysuggestive of DVT. Comparison of calf circumference will often show enlargement of theaffected side. Constitutional findings may include temperature elevation (39.5°-40.5° C), chills,and malaise. Arterial embolism is usually more painful early on, with less swell ing,exaggerated distal temperature decrease, and early sensory deficit. Severe venousthrombosis effecting retrograde arterial flow decrease may result in phlegmasia ceruleadolens, which can result in pedal ischemia and gangrene. Coagulation studies are usually normal unless full blown disseminated intravascular coagulation (DIC). familial antithrombin III deficiency, or lupus erythematosus clotting inhibitors exist. The laboratory diagnosis of DVT hinges on venous non-invasive duplex Doppler examination, andmagnetic resonance venography or contrast venography may be employed if ultrasound isequivocal. Radioactive 1251-fibrinogen scanning, in conjunction with occlusion impedence plethysmography is also a sensitive combination for DVT ofthe calf. Use ofthe D-dimer
testmay also be useful, however combined clinical and venographic tests are more reliable. An accurate diagnosis of DVT is made upon identification of predisposing factors and clinicalobservation, combined with duplex Doppler ultrasound
and, perhaps, magnetic resonancevenogram or contrast venography.Prevention of DVT is recommended, and can be achieved in several different ways (Tables3-6 and 3-7). Prophylactic therapy in the low-risk patient involves mini-dose subcutaneousadministration of 5000 units of heparin every 8 or 12 hours beginning about 60 minutespreoperatively. Adjunct physical measures include support hose, intermittent sequentialpneumatic compression of the lower extremity, leg elevation with the knee flexed, andout-of-bed activity at an early stage after surgery. In high-risk patients, DVT prophylaxis isadministered preoperatively with mini-dose heparinization, however in the postoperativephase, the heparin dose is adjusted upward to keep the PH within 4 seconds of highnormal. Despite statistically more postoperative hemorrhage, this form of DVT prophylaxis appears to be worthwhile in the high-risk patient. A baseline platelet count is recommended prior to mini-dose heparinization, and should be monitored periodically if it is observed tobe low. High-risk patients may also be prophylaxed with a combination of mini-doseheparin and dihydroergotamine, which causes venular constriction and rapid venous return.Other prophylactic combinations include heparin and antithrombin III administration, and theuse of low molecular weight heparin administered once daily has been shown to beeffective and popular (see risk stratification and guidelines for prophylaxis, below).Goumadin, which inhibits the vitamin K-dependent clotting factors II, VII, IX, X, and proteinsG and S, can also be administered preoperatively and during the postoperative phase toeffect DVT prophylaxis.