The FALLS (Fluid Administration Limited by Lung Sonography) protocol:
- The FALLS-protocol is an ultrasound evaluation of patients with acute circulatory failure Includes evaluation of the pleura, lungs, and pericardium using ultrasound in a step-wise fashion to categorize circulatory shock is present according to Weil’s shock classification
1.)Exclude obstructive causes of shock:
– Echo to assess for tamponade and right heart strain (PE)
– Thoracic US to assess tension pox
2.) Assess volume status by assessing lung artifact:
-Cardiogenic shock – distended, non-compressing inferior vena cava and pleural effusions
-Hypovolemic or distributive shock – indicates the need for further fluid administration
The FALLS protocol can help define the critical point when fluid administration is becoming deleterious to the patient (lung saturation) and when to start considering the use of vasopressors along with preparedness for any potential respiratory failure.
Reminder of the basics:
Anterior Chest (Blue points from previous BLUE protocol module (*LINK*))
A-profile: normal lung parenchyma
B-profile: interstitial edema (aka lung rockets)
Applying the protocol:
First evaluate for OBSTRUCTIVE CAUSES OF SHOCK:
Utilize the cardiac probe and perform a basic echocardiogram to assess for obstructive causes of shock. Immediately you can rule out pericardial tamponade and assess for RV enlargement (“D” sign on PSS). Place the probe over the anterior chest and rule out pneumothorax by evaluating lung sliding.
If these are negative – you have effectively excluded obstructive shock. The FALLS protocol will take this one step further to assess for interstitial syndrome.
IF NEGATIVE – RULED OUT OBSTRUCTIVE CAUSE
Second, evaluate for CARDIOGENIC CAUSE OF SHOCK:
Assess for lung rockets. Lung rockets are defined as three or more B-lines in a view between two ribs. (B-PROFILE).The B-line is a particular comet-tail artifact. This indicates pulmonary edema and LV failure/dysfunction
-the detection of an interstitial syndrome and associated lung sliding is defined as the B-profile, and it is largely equivalent to the diagnosis of acute hemodynamic pulmonary edema, with a 97% sensitivity and a 95% specificity
IF NEGATIVE —RULED OUT CARDIOGENIC CAUSE
Thirdly, evaluate for HYPOVOLEMIC SHOCK
Now that obstructive and cardiogenic causes have been ruled out, you can use the FALLS protocol to assess for A-lines (A-PROFILE). The A-profile will combine A-lines with lung sliding. Once the A-profile has been established, who mechanisms of acute circulatory failure are competing: Hypovolemic shock and distributive shock.
A shocked patient who displays the A-profile, at this step, is called a FALLS-responder. This patient can, and needs to receive fluid.
Fourth, assess volume status/ SEPTIC SHOCK
Change from A-profile to the B-profile during fluid resuscitation (volume overload and pulmonary edema). At this step, called FALLS-endpoint, fluid therapy is discontinued. The transformation from an A-profile to a B-profile under fluid therapy without clinical improvement defines, according to the protocol, the septic shock.
Septic shock is the last step of a complete FALLS-protocol. The FALLS-protocol follows the standard of care in septic shock, that is an early and massive fluid therapy.
Lichtenstein D. FALLS-protocol: lung ultrasound in hemodynamic assessment of shock. Heart, Lung and Vessels. 2013; 5(3): 142-147.
The FALLS-Protocol, Another Way to Assess Circulatory Status Using Lung Ultrasound
Daniel A. Lichtenstein. Turk J Anaesthesiol Reanim. 2017 Jun; 45(3): 176–178.
Published online 2017 Feb 1. doi: 10.5152/TJAR.2017.24041