Page 51 - Ultrasonography in Prehospital and Emergency Medicine - Rein Ketelaars
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non-traumatic shock
To evaluate critically ill patients with acute circulatory failure, Lichtenstein devised the fluid administration limited by lung sonography (FALLS)-protocol aimed at reducing the mortal- ity from septic shock.39 It aims to sequentially rule out (1) obstructive, (2) cardiogenic, and (3) hypovolemic shock for expediting the diagnosis of distributive (usually septic) shock, displayed in Figure 2.6. When other causes of shock are eliminated and distributive shock (sepsis) remains, fluid therapy and vasopressors are indicated. Fluid therapy is guided by repeated chest ultrasound based on the appearance of the so-called B-profile as defined in the BLUE protocol (Table 2.1).
ABCDE of prehospital ultrasonography 49
Simple echocardiography
▷ Pericardial tamponade ▷ Pulmonary embolism
Right ventricle dilatation
Lung ultrasound
▷ Tension pneumothorax?
Abolished
lungsliding?
(BLUE → A’-profile)
Lung
ultrasound
▷ Pulmonary edema?
▷ Lung sliding present?
Lung
ultrasound
▷ Lung sliding present?
(BLUE → A-profile)
▷ Start fluid therapy
Look for improve-
ment of shock
Lung
ultrasound
▷ This cause of shock is
remaining
▷ Development of
pulmonary edema without hemodynamic improvement
(BLUE → A-profile
develops into B-profile)
(BLUE → B-profile)
Figure 2.6 FALLS protocol
This diagram is an adaptation of the work by dr. Lichtenstein.39
FALLS protocol. Firstly, this diagram shows the type of shock the focus is on. Secondly, the type of ultrasound examination is shown. Thirdly, possible diagnoses to consider are shown including their appearance in terms of the BLUE protocol. Every cause of shock is sequentially excluded for expediting the diagnosis of distributive (septic) shock.
FALLS, fluid administration limited by lung sonography; BLUE, bedside lung ultrasound in emergency; BLUE and the A, B, and A’-profile are explained in Table 2.1: item 1, 2, and 8, respectively.
The rapid ultrasound in shock (RUSH) examination involves a three-part assessment simpli- fied as (1) the pump, (2) the tank, and (3) the pipes.75 The pump refers to an evaluation of the pericardial sac, left ventricular contractility and the relative size of the right ventricle to the left ventricle. The tank refers to the determination of effective intravascular volume status by measuring the inferior vena cava (IVC) and assessment of the lung, pleural and abdominal cavity. The pipes refer to scanning for an aneurysm or dissection of the thoracic and abdom- inal aorta, and deep venous thrombosis.
2
Obstructive shock?
Cardiogenic shock?
Hypovolemic shock?
Distributive shock (sepsis)
