Title : The BLUE-protocol : Diagnosing hemodynamic pulmonary edema using lung ultrasound
Abstract:
Critical ultrasound was defined in our 1991 publication: “ultrasound for the critically ill, by the critical care physician, whole body ultrasound”. This definition, considering the lung, provides a new definition of ultrasound, now a clinical tool. The BLUE-protocol is a fast protocol enabling immediate diagnosis of acute respiratory failures. It requires a simple gray-scale unit, a microconvex probe. It analyzes ten signs: bat sign (pleural line), lung sliding, A-lines (horizontal artifacts arising from pleural line), quad sign and sinusoid sign indicating pleural effusion, fractal sign and lung sign indicating lung consolidation, B-lines (particular comet-tail artifacts arising from the pleural line among seven criteria), and lung rockets (multiple B-lines, indicating interstitial syndrome), abolished lung-sliding with stratosphere sign, suggesting pneumothorax, lung point indicating pneumothorax. Three points of analysis per lung are defined (two anterior, one caudal and as posterior as possible). Hemodynamic pulmonary edema (HPE), pneumothorax, pulmonary embolism, pneumonia, COPD, asthma, were assessed using CT (gold standard) with sensitivity and specificity ranging from 90 to 100%1. The B-profile is defined by the association of lung-rockets with lung sliding, symmetrical on the four anterior points, without any anterior consolidation. The B-profile is 97% sensitive and 95% specific to HPE, when six factors (the BLUE-factors) are respected1. Simple machine, able to analyze lung ultrasound, respect of the semiology of the B-lines, respect of the definition of the B-profile, patient in acute respiratory failure, BLUE-protocol done during dyspnea, and inclusion of only certain diagnosis of HPE, without intricated other diagnosis (such as pneumonia). The A-line indicates non elevated PAOP2. The BLUE-protocol is a holistic protocol, because it allows estimation of left heart function in numerous settings (critically ill to ambulatory patient, neonates to seniors, wealthy to scarse-resource areas). Shortly, derived products. The FALLS-protocol2 uses, in acute circulatory failure, the B-line as direct parameter of clinical volemia and endpoint for fluid therapy. The SESAME-protocol, used during cardiac arrest3 : very briefly, after exclusion of shockable cause, the lung is analyzed first (pneumothorax), then a carefully chosen venous area (called the V-point) searching for DVT at this location, then search for peritoneal fluid, then search for pericardial tamponade. The very heart comes last. The whole analysis, with our holistic approach, takes far less than one minute (four seconds for the first step, 35 seconds when reaching step 5). CEURF trains since 1989 at the bedside in our ICU.
Audience Take Away
- Purchase simple cost-effective machines with a single, universal probe.
- Immediate diagnosis of hemodynamic pulmonary edema.
- Research applicable to expand teaching or research.
- Provides practical solutions for simplifying and improving efficiency in job roles.
- Offers radiation-free diagnosis.
- Eliminates the need for painful arterial blood puncture.
- Facilitates easy differential diagnoses of acute respiratory failure.
- Simplifies expert Doppler echocardiography.
