Medical Management of Pulmonary Embolism PDF

2/22/24, 2:03 PM Realizeit for Student Medical Management Medical management of the patient with PE revolves around whether the patient is diagnosed with a hemodynamically unstable PE (also called a massive PE) or a stable PE. The patient with a hemodynamically unstable PE, which comprises a life-th...

2/22/24, 2:03 PM Realizeit for Student Medical Management Medical management of the patient with PE revolves around whether the patient is diagnosed with a hemodynamically unstable PE (also called a massive PE) or a stable PE. The patient with a hemodynamically unstable PE, which comprises a life-threatening emergency, may evidence hypotension, tachycardia, confusion, and cardiovascular collapse. Medical Management of Unstable Pulmonary Embolism The immediate objective is to stabilize the cardiopulmonary system in the patient with a hemodynamically unstable PE. A sudden increase in pulmonary resistance increases the work of the right ventricle, which can cause acute right-sided heart failure with cardiogenic shock. Emergent measures are initiated to improve respiratory and cardiovascular status. After emergency measures have been initiated, the treatment goal is to lyse (dissolve) the existing embolus and prevent new ones from forming. Thrombolytic therapy with t-PA or other agents such as reteplase is used in treating unstable PE, particularly in patients who are severely compromised (e.g., those who are hypotensive and have significant hypoxemia despite oxygen supplementation) (Ouellette, 2019). Thrombolytic therapy lyses the thrombi or emboli quickly and restores hemodynamic functioning of the pulmonary circulation, thereby reducing pulmonary hypertension and improving perfusion, oxygenation, and cardiac output. However, the risk of bleeding is significant. Contraindications to thrombolytic therapy include having had a stroke within the past 2 months, other active intracranial processes, active bleeding, surgery within 10 days of the thrombotic event, recent labor and delivery, trauma, or severe hypertension. Consequently, thrombolytic agents are advocated only for PE affecting a significant area of blood flow to the lung and causing hemodynamic instability (Tapson & Weinberg, 2020). Before thrombolytic therapy is started, INR, aPTT, hematocrit, and platelet counts are obtained. Any anticoagulant is stopped prior to administration of a thrombolytic agent. During therapy, all but essential invasive procedures are avoided because of potential bleeding. After the thrombolytic infusion is completed (which varies in duration according to the agent used), maintenance anticoagulation therapy is initiated. A surgical embolectomy is rarely performed but may be indicated if there are contraindications to thrombolytic therapy. Embolectomy can be performed using catheters or surgically. Surgical removal must be performed by a cardiovascular surgical team with the patient on cardiopulmonary bypass (Ouellette, 2019). For patients who have recurrent PE despite therapeutic anticoagulation, an inferior vena cava (IVC) filter may be inserted (Tapson, 2019). IVC filters are not recommended for the initial treatment of https://herzing.realizeithome.com/RealizeitApp/Student.aspx?Token=lqf9HhURQ5RqpgqAkzH2zSNYYvz6N%2bxRwegtqPK%2fJ7UsPJxuq7nE1D4sTAvq22Nk5Sl… 1/3 2/22/24, 2:03 PM Realizeit for Student patients with PE and should not be used in patients receiving anticoagulants. The IVC filter provides a screen in the IVC, allowing blood to flow unobstructed while large emboli from the pelvis or lower extremities are blocked or fragmented before reaching the lung. Numerous devices have been developed since the introduction of the original Greenfield filter. Medical Management of Stable Pulmonary Embolism In patients with PE who do not demonstrate any cardiopulmonary instability (e.g., normotensive, no evidence of hypoxemia) immediate anticoagulation is indicated to prevent recurrence or extension of the thrombus and may continue for 10 days (Tapson, 2019). Long-term anticoagulation is also indicated up to 6 months following the PE and is critical in preventing recurrence of VTE. This duration may be extended indefinitely in patients who are at high risk for recurrence (Weinberger et al., 2019). In patients with stable PE, the initial anticoagulant selected may include an LMWH (e.g., enoxaparin), unfractionated heparin, or a direct oral anticoagulant (DOAC), such as a direct thrombin inhibitor (e.g., dabigatran), or a factor Xa inhibitor (e.g., fondaparinux, rivaroxaban, apixaban, edoxaban) (Tapson & Weinberg, 2020). In select patients with PE who are hemodynamically stable, outpatient therapy can be started by administering the first dose in the emergency department or urgent care center and the remaining doses given at home. Although there are not specific selection criteria for outpatient treatment, the patient is usually at low risk of death, has no respiratory or hemodynamic compromise, does not require opioids for pain control, has no risk factors for bleeding, has no serious comorbid conditions, and has stable baseline mental status with a good understanding of the benefits and risks of treatment (Tapson, 2019). The ideal agent for outpatient administration is not empirically confirmed, although the DOACs are often prescribed. Long-term treatment options include warfarin and the DOACs. An LMWH may also be selected but is usually not prescribed for long-term therapy since it is given via a subcutaneous injection. Warfarin dosing requires regular blood draws for INR monitoring and has a higher bleeding risk, but it has long been the standard of care prior to the development of DOACs. An antidote (vitamin K) is available if the INR is high and there is a risk of bleeding. Warfarin does have interactions with several medications and has dietary restrictions. DOACs do not require regular blood test monitoring; however, they are more costly than warfarin. The choice of warfarin versus a DOAC is dependent upon risk of bleeding, cost, presence of comorbidities, and provider preference (The Joint Commission [TJC], 2019). https://herzing.realizeithome.com/RealizeitApp/Student.aspx?Token=lqf9HhURQ5RqpgqAkzH2zSNYYvz6N%2bxRwegtqPK%2fJ7UsPJxuq7nE1D4sTAvq22Nk5Sl… 2/3 2/22/24, 2:03 PM Realizeit for Student https://herzing.realizeithome.com/RealizeitApp/Student.aspx?Token=lqf9HhURQ5RqpgqAkzH2zSNYYvz6N%2bxRwegtqPK%2fJ7UsPJxuq7nE1D4sTAvq22Nk5Sl… 3/3