Ratzlaff, Robert A.

Abstract Training adult learners to use ultrasound in clinical practice relies on the ability of the learner to apply visuospatial concepts to the anatomy of the human body. We describe a visuospatial trainer that replicates the housing of an ultrasound transducer, through which a linear laser projects light in the same plane and orientation as the ultrasonic sound waves. We use this trainer in combination with a porcine heart dissection laboratory to teach bedside cardiac ultrasound and transthoracic echocardiography (TTE). Off-the-shelf components, including an on/off switch, a laser, and 2 ampere batteries are connected in series and placed inside the 3-dimensional (3D)–printed housing. The trainer's laser emission projects a red line that visually represents the ultrasound's field. Learners project the laser against a porcine or human heart in the orientation of the TTE window they wish to obtain and then dissect the heart in that plane, allowing for visualization of how grayscale images are obtained from 3D structures. Previous research has demonstrated that visuospatial aptitude is correlated with ultrasound procedural performance. We present this trainer and educational method as a specific training intervention that could enhance the visuospatial ability of the ultrasound learner. This visuospatial trainer and educational method present a novel process for enhancing learner understanding of 2-dimensional ultrasound images as they relate to 3D structures. Having a clear understanding of how images are generated in cross section may translate into more proficient adaptation of cardiac ultrasound and TTE.

A 58-year-old man with medical history of thrombocytopenia was admitted to an outside hospital for a 6-day history of worsening dyspnoea requiring mechanical ventilator support. He was transferred to our institution for extracorporeal membrane oxygenation (ECMO) given his refractory hypoxaemia. On arrival, H1N1 influenza virus was confirmed and all measures to improve oxygenation were ineffective. Thus, the decision was made to start venovenous (VV)-ECMO. Although a low baseline platelet count was recognised (60–70×109/L), a sudden further decrease occurred (30×109/L) and platelet transfusion was initiated. A substantial increase in the pressure across the ECMO oxygenator was identified, and the diagnosis of type II heparin-induced thrombocytopenia was suspected and confirmed. Heparin was discontinued, the oxygenator was exchanged and argatroban was used for anticoagulation. After 28 days on VV-ECMO support, the decision was made to withdraw organ support in conjunction with the patient and family wishes.

Giant cell myocarditis (GCM) is a rare and commonly fatal form of fulminant myocarditis. During the acute phase, while immunosuppressive therapy is initiated, venoarterial extracorporeal membrane oxygenation (VA-ECMO) support is commonly used as a bridge to heart transplantation or recovery. Until recently, conventional transesophageal echocardiography and transthoracic echocardiography were the tools available for hemodynamic assessment of patients on this form of mechanical circulatory support. Nevertheless, both techniques have their limitations. We present a case of a 54-year-old man diagnosed with GCM requiring VA-ECMO support that was monitored under a novel miniaturized transesophageal echocardiography (hTEE) probe recently approved for 72 hours of continuous hemodynamic monitoring. Our case highlights the value of this novel, flexible, and disposable device for hemodynamic monitoring, accurate therapy guidance, and potential VA-ECMO weaning process of patients with this form of severe myocarditis.