Shock Syndromes II

of fluid overload complications are greater with plasma

(Answer B is correct).

Answer: A

The patient has a massive PE, as evidenced by pulseless

activity. Massive PE should be treated with thrombolytic

therapy unless absolute contraindications to thrombo-

lytics are present. Prolonged chest compressions may be

considered a relative contraindication to thrombolytics,

but this patient had a short duration of chest compres-

sions (Answer A is correct). Troponin T and brain

natriuretic concentrations may help classify a patient as

having a submassive PE, but the patient in this case has

already fulfilled the criteria for a massive PE, and these

laboratory values will not change the patient’s treatment

(Answers B and C are incorrect). Although a TTE might

provide information on RV function, it is unlikely to

change the patient’s treatment plan with thrombolytics

and might delay therapy (Answer D is incorrect).

Answer: B

This patient’s PE is causing stress on the RV, as evi-

denced by his echocardiogram and positive cardiac

enzymes. Therefore, this is not a low-risk PE (Answer

D is incorrect). However, the patient is hemodynami-

cally stable at this point, so it is also not a high-risk PE

(Answer A is incorrect). Given that the patient has both

evidence for RV straining and myocardial ischemia as

represented by both the echocardiogram and the cardiac

enzymes, this meets the criteria for an intermediate-high

risk PE (Answer B is correct; Answer C is incorrect).

Answer: B

This patient appears to be clinically worsening with

blood pressures that are approaching hemodynamic

instability and worsening oxygenation requiring high

levels of Fio2. Consideration for reperfusion therapy is

warranted. Given his history of a recent GI bleed requir-

ing ICU admission, systemic, full-dose thrombolytics

would be contraindicated (Answer A is incorrect). A

thrombolytic strategy to minimize the risk of bleeding

may be appropriate. Although half-dose alteplase has

been studied, it is not recommended because of insuf-

ficient evidence (Answer C is incorrect). Therefore, in

intermediate-high risk PE with clinical deterioration, the

guidelines recommend CDT when systemic thrombo-

lytic contraindications exist and resources are available,

such as in an urban, academic ICU. Catheter-directed

thrombolysis is administered with mechanical meth-

ods (e.g., ultrasound-assisted thrombolysis) and specific

catheters (not pulmonary artery catheters) (Answer B is

correct; Answer D is incorrect).

Answer: A

This patient now has a cardiac arrest secondary to his

PE. Because he has a confirmed PE as the precipitant of

cardiac arrest, systemic thrombolytic is recommended

as an emergency treatment. Given the mortality rates

from PE in a cardiac arrest, standard contraindications

to thrombolysis may be suspended in favor of a lifesav-

ing intervention. Systemic thrombolytics in this setting

may be associated with return of spontaneous circulation

and possibly survival benefits (Answer D is incorrect).

The recommended alteplase dose is a 50-mg intrave-

nous bolus, repeated in 15 minutes if needed (Answer

A is correct; Answer C is incorrect). Although surgi-

cal embolectomy would be reasonable in the operating

room, systemic thrombolytics would be preferred, given

the patient’s current location in the ICU (Answer B is

incorrect).

Answer: D

This patient is experiencing a high-risk or massive PE,

as evidenced by a confirmed CT scan, clinical signs

consistent with a PE, and a dilated right ventricle on

TTE in the setting of sustained hypotension requiring

norepinephrine. Although an inferior vena cava filter

may prevent additional embolization, it will not limit the

growth or cause lysis of the current clot burden associ-

ated with his PE (Answer A is incorrect). For a high-risk

or massive PE, administration of systemic thrombolytic

agents is recommended unless contraindications are

present. Because this patient had a recent subarachnoid

hemorrhage, the risk of systemic thrombolytic therapy

might outweigh the potential benefit (Answer B is incor-

rect), even at a reduced dose (Answer C is incorrect).

Therefore, the CHEST guidelines recommend CDT for

patients who are hemodynamically unstable from a PE

but have a high bleeding risk (Answer D is correct).