Table 2 Summary of typical findings in different types/causes of shock by SIMPLE approach
From: Make it SIMPLE: enhanced shock management by focused cardiac ultrasound
Type of shock | Hypovolemic | Cardiogenic | Septic | Distributive | Pulmonary embolism | Cardiac Tamponade | Aortic Dissection | |
|---|---|---|---|---|---|---|---|---|
S | Chamber size | Small LV | Dilated LV | Early: small LVESA Late: normal/dilated | Near normal LVEDA but small LVESA | Dilated RV, small/normal LV | Diastolic collapse of RA and RV; normal LV | Usually normal |
I | IVC thickness | Collapsed | Distended <50 % respiratory collapse | Early: collapsed Late: distended | Collapsed | Distended and loss of respiratory collapse | Distended and loss of respiratory collapse | Normal when no cardiac tamponade |
IVS movement | Normal | Reduced | Early: normal Late: reduced | Normal | Paradoxical IVS and D-shaped LV | Normal | Normal | |
Intimal flap | Absent | Absent | Absent | Absent | Absent | Absent | Present | |
M | Myocardial thickening/motion | Hyperdynamic | Hypokinetic | Early: hyperdynamic Late: hypokinetic | Hyperdynamic or normal | McConell’s sign, LV hyperdynamic | Diastolic collapse of RA and RV | Normal if coronary ostia not involved |
Masses in heart | Absent | Intramural thrombi if AF/AMI | Absent | Absent | Thrombi in RA/RV and IVC | Absent | Absent | |
P | Pericardial effusion | Absent | Small amount if inflammatory cause | Absent | Absent | Absent | Moderate to large but can be small if acutely collected | Present if retrograde dissection and echogenic |
Pleural effusion | Absent | Present | Present if pneumonia | Absent | Usually absent | Absent | Present if hemothorax | |
L | LV systolic function | Hyperdynamic | Poor | Early: normal or hyperdynamic Late: impaired | Normal or hyperdynamic | Normal or hyperdynamic | Normal | Normal |
E | Abdominal aorta in epigastrium | Aneurysmal if due to AAA rupture | Normal | Normal | Normal | Normal | Normal | Intimal flap seen |