Utility of transthoracic echocardiography in diagnosis and treatment of cardiogenic shock during noncardiac surgery

Perioperative Point-of-Care Ultrasound Use by Anesthesiologists

Point-of-Care ultrasound (POCUS) is the bedside utilization of ultrasound, in real-time, to aid in the diagnosis and treatment of patients. Image acquisition from POCUS utilization by anesthesiologists involves the assessment of multiple organs in different perioperative situations. POCUS can be utilized to enhance clinical decision-making in a variety of perioperative situations due to its ability to assess endotracheal tube placement, cardiac function, pulmonary function, aspiration risk, hemodynamics, vascular access, and nerve visualization for regional procedures. The mounting clinical evidence for the value of POCUS in perioperative settings, its growing affordability, and its low associated risks are responsible for the nationwide movement across many anesthesiology residency programs to increase the focus on perioperative ultrasound training. The purpose of this review is to present to current anesthesiologists and anesthesiology trainees, a broad discussion regarding the diverse utility and importance of POCUS in perioperative settings.

Point-of-care ultrasound in pediatric anesthesia: perioperative considerations

PURPOSE OF REVIEW

To review the perioperative applications of point-of-care ultrasound (POCUS).

RECENT FINDINGS

The role of point-of-care ultrasonography for perioperative care is expanding with respect to perioperative application. The imaging approach can complement the physical exam and provide additional information for decision-making in pediatric perioperative medicine. This review will focus on applications in the following organ systems: airway, cardiac, pulmonary and gastric. Specifically, POCUS of the airway has been used to optimize endotracheal tube depth, aid in tube size selection and predict difficulty with laryngoscopy and intubation. Lung POCUS has been used to assess for causes hypoxemia as well as to optimize ventilatory mechanics. Cardiac POCUS has been used for assessment of hemodynamics, valvular and ventricular function. Gastric ultrasound has emerged as an evaluative mechanism of gastric content in the setting of fasting as well as to confirm placement of gastric tubes. The applications of POCUS in the perioperative setting continue to evolve as a reliable diagnostic tool that can assist in timely diagnosis, improve procedural safety and has the potential to improve patient outcomes.

SUMMARY

The utility of perioperative POCUS has been well demonstrated, specifically for examination of the airway, stomach and cardiopulmonary system. It is advisable for the novice sonographer to perform POCUS within the guidelines set by the American Society of Echocardiography regarding basic POCUS. As with all diagnostic modalities, understanding the limitations of ultrasound and POCUS as well as continuous self-assessment is crucial.

[Knowledge retention after focused cardiac ultrasound training: a prospective cohort pilot study]

BACKGROUND AND OBJECTIVES

Focused Cardiac Ultrasound (FoCUS) has proven instrumental in guiding anesthesiologists' clinical decision-making process. Training residents to perform and interpret FoCUS is both feasible and effective. However, the degree of knowledge retention after FoCUS training remains a subject of debate. We sought to provide a description of our 4-week FoCUS curriculum, and to assess the knowledge retention among anesthesia residents at 6 months after FoCUS rotation.

METHODS

A prospective analysis involving eleven senior anesthesia residents was carried out. At end of FoCUS Rotation (EOR) participants completed a questionnaire (evaluating the number of scans completed and residents' self-rated knowledge and comfort level with FoCUS), and a multiple-choice FoCUS exam comprised of written- and video-based questions. Six months later, participants completed a follow-up questionnaire and a similar exam. Self-rated knowledge and exam scores were compared at EOR and after 6 months. Spearman correlations were conducted to test the relationship between number of scans completed and exam scores, perceived knowledge and exam scores, and number of scans and perceived knowledge.

RESULTS

Mean exam scores (out of 50) were 44.1 at EOR and 43 at the 6-month follow-up. Residents had significantly higher perceived knowledge (out of 10) at EOR (8.0) than at the 6-month follow-up (5.5), p=0.003. At the EOR, all trainees felt comfortable using FoCUS, and at 6 months 10/11 still felt comfortable. All the trainees had used FoCUS in their clinical practice after EOR, and the most cited reason for not using FoCUS more frequently was the lack of perceived clinical need. A strong and statistically significant (rho=0.804, p=0.005) correlation between number of scans completed during the FoCUS rotation and 6-month follow-up perceived knowledge was observed.

CONCLUSION

Four weeks of intensive FoCUS training results in adequate knowledge acquisition and 6-month knowledge retention.

[Perioperative transesophageal echocardiography in non-cardiac surgery. Update]

AIM

The aim of this article is to impart knowledge concerning focused transesophageal echocardiographic examination (TEE) for non-cardiac surgery which is an essential part of perioperative monitoring. It allows a rapid echocardiographic examination without interference with the surgical field or under limited transthoracic examination conditions. New recommendations for a comprehensive perioperative TEE examination with expanded standard views and the recently published consensus statement for a shortened baseline examination were crucial for this study.

MATERIAL AND METHODS

The background is the peer-reviewed literature from PubMed.

RESULTS

Apart from cardiac surgery TEE has two main applications: firstly, the evaluation of patients developing acute life-threatening hemodynamic instability in the operating room, in the emergency room or in the intensive care unit (ICU). Secondly, TEE is used as planned intraoperative monitoring when severe hemodynamic, pulmonary or neurological complications are expected because of the type of surgery or due to the cardiopulmonary medical history of the patient. In 2013 a total of 11 relevant standard views were defined for the basic perioperative TEE examination in non-cardiac surgery. These 11 views should be performed for each patient. Appropriate extension to a comprehensive examination may be necessary if complex pathology is obvious.

DISCUSSION

Even in non-cardiac surgery TEE is an important tool allowing clarification of a life-threatening perioperative hemodynamic instability within a few minutes. Furthermore, the hemodynamic management of high-risk patients can be facilitated. Appropriate qualification and continuous training are necessary in order to assure the competence of the examiner.

Perioperative Echokardiographie

Over the past decades, echocardiography has undergone a continuous evolution in technology that has promoted its clinical application and acceptance throughout perioperative medicine. These technological advances include improvements in transducer development that permit superior imaging quality and a wider selection of probes for epicardial, epiaortic, and surface echocardiography which can also be used in conjunction with multiplane transesophageal echocardiography. Moreover, the addition of Doppler technology and digital acquisition has secured the role of echocardiography as a valuable and relatively noninvasive diagnostic tool for the assessment of cardiovascular disease and hemodynamic monitoring throughout the perioperative period. Therefore, it has become increasingly important for perioperative physicians to understand the basic principles and underlying fundamental concepts pertaining to the technology and physics of echocardiography, as well as its inherent limitations. The current review outlines the modes and applications of different echocardiographic techniques used in perioperative echocardiography including M-mode, two-dimensional echocardiography, and Doppler assessment of blood flow. In addition, the limitations of these techniques and typical artifacts associated with the perioperative use of echocardiography are described.