PULMONARY VASCULAR

PE pulmonary emboliIn patients with recognized massive PE, the incidence of physical signs has been reported as follows:96% have tachypnea (respiratory rate >16/min)58% develop rales53% have an accentuated second heart sound44% have tachycardia (heart rate >100/min)43% have fever (temperature >37.8 C)36% have diaphoresis34% have an S3 or S4 gallop32% have clinical signs and symptoms suggesting thrombophlebitis24% have lower extremity edema23% have a cardiac murmur19% have cyanosis

venous thrombi (i.e., blood clots) detach from their sites of origin on blood vessel walls, travel through the blood to the lungs, obstruct blood vessels, and reduce blood flow. Most pulmonary thromboemboli (95%) arise in the deep veins of the lower extremities. Approximately 650,000 patients develop PTE annually, resulting in a quarter-million hospitalizations.Pulmonary thromboembolism occurs in 6080% of patients with DVT, eventhough more than half the patients are asymptomatic. Sixty percent of patients who die in the hospital have experienced PTE. Because patients with PTE present with non-specific clinical manifestations, the diagnosis is missed in approximately 400,000 individuals in the United States each year. Virtually every primary healthcare provider encounters patients who are at risk for PTE.

Pulmonary thromboembolismEmbolism: It is a detached solid, liquid or a gaseous mass carried through the blood to a distant site from its point of origin.TYPES: Blood clot.Rare causes: fat, air, amniotic fluid.

Most common cause for P.E is DVT (deep venous thrombosis) of lower extremities.-Femoral vein.-Pelvic veinsRisk factors: For pulmonary thromboembolism are same as for DVT.

Because of impaired venous return and locally increased venous pressure, a lower extremity with a deep vein thrombosis is often dusky red and edematous, as seen in this image.

RISK FACTORSPhysiological factors contributing to venous thrombosisA-Venous stasisB-Endothelial cell injuryC- Hypercoagulable states

RISK FACTORS Prologed bed rest: trauma, surgery (orthopedic, (femur , hip) gynecological cancer).Congestive cardiac failure/Atrial fibrillation.Myocardial Infarction/mural thrombous.Spinal cord injury.Cancer patients.Pregnancy, child birth, oral contraceptives (smoking >35y), HRT (hormone replacement therapy)

PathophysiologyThe effect of pulmonary embolism is: A- Mechanical obstruction of pulmonary circulation.B- Vasoconstriction.(rule of pulmonary circulation is hypoxia leads to vasoconstriction) C-Bronchoconstriction (AS A Reflex in the affected areas of lungs)

CONTD -Wasted ventilationImpaired gas exchange.HypoxemiaChronic thromboembolic phenomena leads to Pulmonary hypertension and eventually right sided heart failure.Large embolism causes: Acute right sided heart failure if lodges in pulmonary trunk.

This image illustrates a large pulmonary thromboembolus from an autopsy performed on an elderly woman who died suddenly while hospitalized for evaluation of an abdominal mass. The main pulmonary artery has been opened anteriorly to reveal a massive thromboembolus that straddles the bifurcation of the main pulmonary artery and completely occludes the right and left pulmonary arteries. Postmortem examination of the abdomen revealed a mucin-producing adenocarcinoma (cancer) of the sigmoid colon that had spread throughout much of the peritoneal cavity.

This is a closer view of the pulmonary thromboembolus illustrated in the previous image, demonstrating complete occlusion of both the right and left pulmonary arteries by the saddle embolus. Delicate fibrin-platelet lamellae, or lines of Zahn, are visible on the external surface of the thromboembolus.

Clinical manifestationsDepends on the size of embolus and location of the obstruction.MODERATE SIZED EMBOLUS:Most common symptoms: Chest pain(Pleuritic type). Dyspnea and apprehension. Increased Respiratory Rate. Mild fever. Cough productive of sputum.

Massive embolus: Chest pain, shock. Weak pulse and low BP. Distended neck veins. Cyanosis.

DIAGNOSISCTPAClinical suspicion.Blood gases.(low PO2 and Normal PCO 2

*Thrombus locally occurring Emboli coming from somewhere else

Leading cause of death in hospitalized ptsSudden collapse on the street is most likely pe, not mi

These numbers show that the signs are hard to pinpoint pe. They could be anything

Thrombophlebitis flex foot and get leg pain

There are no giveaway signs that something is a peNeed to do coronary ct scan angiogram with contrast to accurately diagnose. But cant just do these based on the signs they are showing. Usually pts are just sent home, usually with some other diagnosis*****Virchows triad for risk of developing venous thrombosis

A Venous stasis sedentary lifestyle, bedridden, wheelchair, recent bone sx, etcB d/t smoking, HTN, stress turn off NO C cancer, pregnancy

Venous clot comes from body (usually leg veins), thru heart, then into lungs. Lungs do have ability to break down clots on its own, but damaged lungs cant do this well. *A-fib quivering of atria, so clots dont get broken down in heart. Artificial joints, valves, anything that is foreign in bodyMural thrombous formation of thrombus in contact with endocardial lining of heart chamberCancer just simply increases clotting

*Bronchoconstriction bc if lung is affected, body will stop sending blood to that area of the lung.*Black clot is massive p.e. First sign is sudden death*Pleuritic chest pain changes when you breathDyspnea, apprehension, anxiety d/t low oxygen in brainIncr resp rate compensation mechanismThese wont point you right to pe, but need to take history to see if they have the risk factors**Ctpa cat scan pulmonary angiogram

Clinical suspicion same as with mi, you need to know what to look for to test for it.

Blood gases blood from radial artery (oops, go thru radial nerve to get to artery). Can measure co2, o2, ph of blood better than from vein. If near 80s then prob peArterial blood gas will usually show hypoxemia and hyperventilation (respiratory alkalosis)

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