Chapter 151 - Pulmonary embolism Flashcards
Mortality of acute PE
10% 3 months
Consequences of PE
1) hypoxemic vasoconstriction 2) increase pulmonary resistance 3) increase right ventricular afterload 4) RV hypokinesis and dilation 5) tricuspid regurtication 6) RV failure 7) decrease CO
Non-resolved thromboemboli in PE
fibrotic deposits –> chronic pulmonary hypertension and RV dysfunction
Symptoms of PE
1) dyspnea 2) chest pain (pleural irritation from pulm infarction) 3) hemoptysis
Signs of PE
1) tachypnea 2) tachycardia 3) rales 4) decreased breath sounds 5) jugular venous distension 6) fever 7) hypotension <10%
Clinical impression of PE sensitivity and specificity
85% sen, 51% spe
Lab test for PE
1) leukocytosis 2) elevated LDH 3) elevated AST 4) elevated CRP/ESR
D dimer level that excludes PE
< 500 mg/L age X 10 mg/L older than 50 excludes only if also low clinical suspicion
Biomarker for RV dysfunction
1) troponin (0.1 ng/ml TnT; 0.4 ng/ml TnI) 2) BNP (90 pg/ml) 3) NT-proBNP (600 pg/ml)
S1Q3T3 explained
prominent S wave in lead 1 Q wave and inverted T wave in lead 3 sign of acute RV overload (cor pulmonale) reflecting strain
Fleischner sign
Enlarged pulmonary artery on CXR
Hampton hump
Peripheral wedge of airspace opacity showing lung infarction on CXR
Westermarck sign
Regional oligemia on CXR
Knuckle sign
Abrupt tapering or cutoff of pulmonary artery
PIOPED (Prospective investigation of pulmonary embolism diagnosis) II trial on CTPA sen and spe
83% sen; 96% spe
RV dysfunction on CTPA
Right to left ventricular end diastolic dimentional ratio > 0.9
Right heart strain increases death with PE by
2x
TAPSE (tricuspid annular plane systolic excursion)
quantitative echo parameter least user dependent most reproducible = 1.6 cm is intermediate risk
McConnell sign
depressed contractility of RV free wall compared with RV apex
Thrombus in transit
thrombus inside the RV rare finding
Rate of LE DVT in PE
30-50%
PE with confirmed DVT have this much increased mortality
2x
Ventilation/perfusion scan in PE uses
Only if CTPA contraindicated sensitive but non-specific
Wells score for PE
TABLE 151.1
Revised Geneva score for PE
TABLE 151.1
Diagnostic algorithm for PE
FIGURE 151.2
Definition of low risk PE and associated mortality
1) normotensive 2) no RV dysfunction 3) no elevated cardiac biomarker 40% of all cases are low risk mortality <2%
Definition of intermediate risk PE and associated mortality
1) normotensive 2) RV dysfunction OR 3) elevated cardiac biomarker 55% of all PE are this group mortality 3-15%
Definition of high risk PE and associated mortality
1) hemodynamically unstable SBP < 90 or cardiac arrest 5% of all PE Mortality 15-30% >60% if need CPR
European society of cardiology: intermediate low vs intermediate high risk PE
Intermediate low = RV dysfunction only intermediate high = RV dysfunction with positive biomarker (trop or BNP/pro-BNP)
Pulmonary embolism severity index (PESI)
TABLE 151.2 PESI III to V - mortality 30 day 24.5% PESI simplified >/= 1 = mortality 11%
Heart-type fatty acid binding protein (HFAB)
> 6 mcg/lt is marker for intermediate risk PE
Marker of non-low risk PE on echo
1) RV/LV EDD > 1 2) TAPSE < 1.6 cm 3) TRJV (jet velocity) > 2.6 m/s 4) estimated RV SBP < 52 mmHg 5) McConnell sign 6) IVC collapsibility > 50% 7) RV hypokinesia 8) left shift of interventricular septum
Goal of treating PE
1) prevent mortality 2) prevent late-onset chronic thromboembolic pulmonary HTN
Initial supportive therapy of PE
1) ABC 2) oxygen to keep sat > 90 3) IV fluid small volume bolus 4) norepinephrine - less likely to cause tachy 5) anticoagulation
Indication for IVC filter
1) contraindication to anticoagulation 2) PE despite adequate anticoagulation 3) unclear if benefit in severe PE with hemodynamic instability as a combined effect with anticoag
Thrombolysis in PE key points
1) greatest benefit in 48 hr 2) still benefit in 14 days 3) high risk patients; maybe intermediate (controversial) 4) standard route is IV via peripheral line but catheter gaining popularity
Regimen for systemic thrombolysis in PE
1) 100 mg alteplase over 2 hrs 2) hold heparin during thrombolysis 3) reteplase and desmoteplase also can be used
Mortality benefit in high risk PE with systemic thrombolysis
1) all cause mortality 47% to 15% 2) PE related mortality 42% to 8.4%
Risk of major bleeding with thrombolysis in PE
1) 9.24 vs 3.42% 2) higher intracranial bleed 3) major risk pt age > 65
ULTIMA trial key points
1) RCT ultrasound assisted CDT vs anticoag 2) RV function improved faster 3) bleeding 3.5%
Catheter directed thrombolysis complications
1) bleed 2) contrast-induced nephropathy 3) device complications 4) access problems 5) heart and lung injuries still less than systemic thrombolysis
Dose of tpa in CDT in PE
15-25mg
Treatment endpoint of CDT in PE
1) high risk then hemodynamic stability 2) intermediate risk then clinical improvement, improved pulmonary artery pressure or right heart strain 3) complete clot removal should not be endpoint
Angiojet rheolytic thrombectomy system in PE
black box FDA warning with increased adverse events and death
Vortex AngioVac aspiration system
1) extracorporeal bypass circuit 2) drainage filtration and reinfusion of blood cleared from clot 3) 26F delivery sheath from IJ or femoral needed 4) no lytics needed
Surgical thrombectomy in PE steps
1) median sternotomy with cardiopulmonary bypass 2) pulmonary artery opened the material extracted 3) right atrium + ventricle explored for possible thrombi 4) close foramen ovale
Surgical thrombectomy in PE indication
1) refractory shock with contraindication or failed lytic
Mortality of surgical thrombectomy in PE
10-30%
Conditions for early discharge after PE
1) low risk PE from PESI score 2) normal hemodynamic 3) no oxygen 4) no bleeding risk factors 5) no serious comorbid conditions 6) mental capacity to consent 7) has social support if deteriorate 8) absence of symptomatci DVT
PE suspicion algorithm
FIGURE 151.7
Incidental subsegmental PE treatment
1) anticoagulate 2) hold if high risk of bleeding
Thrombus in transit mortality
40%
Pregnancy PE
1) LMWH adjusted dose 2) lytics can be used in pregnancy with similar risk to non-pregnant population
Non-thrombotic pulmonary embolism types
1) adipocytes 2) amniotic cells 3) tumor cells 4) bacteria/fungi 5) gas 6) foreign material
Triad of fat embolism
1) pulmonary (respiratory distress) 2) central nervous system (altered mental status) 3) skin (petechial rash)
Triad of amniotic fluid embolism
1) sudden hypoxia 2) hypotension 3) coagulopathy
Air embolism lethal volume
100-500 ml
Treatment of air embolism
Place patient in left lateral decubitus to prevent RV outflow obstruction by airlock
Risk of recurrent PE at 1, 5 10 years
13% 1 year 23% 5 year 30% 10 years
CTEPH definition
Mean pulmonary-artery pressure > 25 mmHg for 6 months after PE
CTEPH symptoms
1) dyspnea 2) fatigue 3) exercise intolerace
Rate of CTEPH after PE
2-4% usually within 2 years
