pulmonary circulation

Deep venous thromboembolism (DVT) patho

-stasis blood flow: impaired blood flow

-endothelial damage: trauma

-hypercoagulability

DVT RF

-pregnancy

-surgery

-immobility

-hypercoagulable disorder

-smoking

-obesity

DVT sx

-lower extremity sx: swelling, pain, warmth, erythema

-usually unilateral

-difference in calf or thigh circumference

-tenderness

-dilated superficial veins

-malignancy

-homans sign: calf pain on dorsiflexion

DVT dx

-pre test probability: using Wells score

-d-dimer: low level using to r/o VTE with low PTP

-diagnostic: compression venous ultrasonography= "wink"

-veins collapse under light pressure

-artery pulsate

acute LE DVT tx

blood cultures w/o absolute contraindication= anticoagulation

-proximal DVT with absolute contraindication= IVC filter placement

-40% of distal DVT= resolve

absolute contraindications

-active major bleeding

-acute intercranial or spinal hemorrhage

-major trauma

-high bleeding risk surgery

-severe bleeding diathesis

-severe thrombocytopenia

DVT tx

-stable pt: rivaroxaban, apixaban

-high risk bleed: unfractionated heparin

-cancer: LMW heparin

-kidney failure: unfractionated heparin

-pregnant: LMW heparin

anticoagulation tx

-warfarin: coumadin, dosed by INR

-heparin: unfractionated (IV), LMW (enoxaparin)

-DOACs: thrombin activity, Xa

-factor Xa inhibitor: rivaroxaban, apixaban

bridging heparin

-warfarin: start warfarin and continue heparin until INR is >2 for at least 2 measurement taken 24 hrs apart

-LMW: stop IV hep within 1 hour start LMWH or SUBQ hep

-DOAC: start when heparin is stopped

pulmonary embolism (PE)

most commonly caused by embolization of a thrombus from leg that enters the pulmonary artery circulation and obstructs a vessel

PE patho

-endothelial injury, promote platelet adhesion, blood stasis and hypercoagulation > more coagulants to accumulate than usual > obstruction

PE RF

-hx of VTE

-virchow'sP triad

-rogers risk score: postoperative VTE allows for appropriate prophylactic measures

PE sx

-sudden onset SOB

-pleuritic chest pain increased with inspiration

-unilateral leg swelling (DVT)

-dyspnea , tachycardia

-maybe cough, hemoptysis

-tachypnea, crackles, diaphoresis, fever, neck vein distension

-massive: shock, syncope, cyanosis

-persistent hypotension > MASSIVE PE = emergency CT pulmonary angiography

PE dx

-wells score

-ECG: dx other condition like MI

-CXR: helpful to find other cause

-venous ultrasound:

-CTA: first line

-V/Q scan: have contraindication to CTA

-pulmonary angiography: gold standard, rarely used

workup based on wells score

-low: PERC or D Dimer

-moderate: D DImer

-high: CTPA

CTA-first line

pulmonary angiography: gold standard

V/Q scan: pt who need CTA but have contraindication to contrast dye

PE lab workup

-CBC: hemoglobin, platelets

-CMP: renal function, LFT

-coagulation studies: PT/INR, PTT

-NT-pro BNP: ventricular cardiomyocytes seen in volume and pressure overload

-D-Dimer

-ABG: hypoxia, respiratory alkalosis

PE classification

-unstable: massive or high risk PE results in hypotension

-systolic BP <90

-or drop in systolic BP >40 from baseline

-stable: small, mild or asymptomatic

-mild hypotension that stabilizes with fluid therapy

low and intermediate risk PE tx

-without cancer: rivaroxaban, apixaban

-long term: NOACs for 3 months

-with cancer: LMWH for 3-6 months

high risk PE, shock, or hypotension tx

-IV unfractionated heparin

-thrombolytic therapy if shock is present

PE surgery

-inferior vena cava filters: if anticoagulation is contraindicated

-catheter based thrombus removal: acute PE with sx of shock, hypotension, high bleeding risk, failed thrombolysis