Shock Syndromes II
| (3) | Persistent hypotension (SBP less than 90 mm Hg or SBP decrease of 40 mm Hg or |
|---|
greater for more than 15 minutes, not caused by new-onset arrhythmia, hypovolemia,
or sepsis)
| (b) | Intermediate-risk or submassive PE. |
|---|---|
| (1) | AHA 2011 classification: Acute PE without systemic hypotension but with either (1) |
RV dysfunction (RV dilation or systolic dysfunction on echocardiogram, RV dilation
on chest CT, brain natriuretic peptide greater than 90 pg/mL, N-terminal pro-brain
natriuretic peptide greater than 500 pg/mL, or electrocardiographic changes [new
complete or incomplete right bundle-branch block, anteroseptal ST-segment elevation
or depression, or anteroseptal T-wave inversion]) or (2) myocardial necrosis (troponin
I greater than 0.4 ng/mL or troponin T greater than 0.1 ng/mL) (2) ESC/ERS 2019
classification: Simplified Pulmonary Embolism Severity Index score of 1 or greater
(i.e., age older than 80; cancer, chronic respiratory disease, or cardiac disease; heart
rate 110 beats/minute or greater; SBP less than 100 mm Hg; or Sao2 less than 90%),
regardless of whether there is RV strain
| (c) | Intermediate-risk PE may further be classified by the presence of both RV dysfunction and |
|---|
myocardial necrosis, termed intermediate-high risk. If only RV dysfunction or myocardial
necrosis is present, it is classified as intermediate-low risk.
| (d) | Low-risk PE: Acute PE not meeting the definition of massive or submassive PE |
|---|
Thrombolytics in cardiac arrest:
| (a) | The 2020 AHA International Consensus on Cardiopulmonary Resuscitation and |
|---|
Emergency Cardiovascular Care (Circulation 2020;142:S92-S139) remains unchanged
from the 2015 AHA guidelines, stating there is no consensus on the ideal thrombolytic
dose in PE-associated cardiac arrest. Contemporary examples of dosing regimens include
either an alteplase bolus of 50 mg (repeated if needed to complete a 100-mg intravenous
total dose) or weight-based tenecteplase if PE is confirmed as the contributing cause of
the arrest.
| (b) | The 2020 AHA guidelines have a weak recommendation to administer fibrinolytic drugs |
|---|
for cardiac arrest when PE is the suspected cause of cardiac arrest (very low-certainty
evidence). When PE is the confirmed cause of cardiac arrest, fibrinolytic drugs or
surgical embolectomy or percutaneous mechanical thrombectomy may be used (very low-
certainty evidence). The task force considered increased bleeding risk from fibrinolytics
administered to patients who may not have PE. In the TROICA study, the largest study of
thrombolysis during cardiac arrest, thrombolysis was associated with increased bleeding
risk but no difference in major bleeding complications. The task force concluded that
patients are far more likely to die from cardiac arrest than from treatment.
| (c) | These recommendations are based on possible improved outcomes with thrombolytics in |
|---|
peri-arrest settings, but prospective evaluations are conflicting.
vi.
Thrombolytics in massive PE:
| (a) | The 2021 update to the CHEST guidelines and the 2019 ESC/ERS guidelines recommend |
|---|
systemic thrombolytics for patients with a massive/high-risk PE and an acceptable risk of
bleeding complications.
| (b) | These recommendations are supported by a meta-analysis, which found that in patients |
|---|
with a massive PE, thrombolytics were associated with a lower rate of recurrent PE or
death than heparin alone (9.4% vs. 19.0%; OR 0.45 [95% CI, 0.22–0.92]).