Sonographic diagnosis of pulmonary embolism with cardiac arrest without major dilation of the right ventricle or direct sign of lower limb venous thrombosis

Common pitfalls in point-of-care ultrasound: a practical guide for emergency and critical care physicians

BACKGROUND

Point-of-care ultrasonography (POCUS) is a widely used tool in emergency and critical care settings, useful in the decision-making process as well as in interventional guidance. While having an impressive diagnostic accuracy in the hands of highly skilled operators, inexperienced practitioners must be aware of some common misinterpretations that may lead to wrong decisions at the bedside.

OBJECTIVES

This article provides a revision list of common POCUS misdiagnoses usually found in practice and offers useful tips to recognize and avoid them.

DISCUSSION

The following aspects were selected and reviewed: pericardial effusion vs. pleural vs. ascites vs. epicardial fat; right ventricle dilation in acute pulmonary embolism and inferior vena cava for volume status assessment in cardiac ultrasound; lung point and lung pulse misinterpretations and mirror artifacts vs. lung consolidations in lung ultrasound; peritoneal fluid vs. the stomach and a critical appraisal of gallbladder signs of acute cholecystitis in abdominal ultrasound; the rouleaux phenomenon vs. deep vein thrombosis or acute right strain in vascular ultrasound.

CONCLUSIONS

Following some rules in technique and interpretation, and always integrating POCUS findings into the broader clinical context, most POCUS misdiagnosis can be avoided, and thus patients' safety can be enhanced. Being aware of a list of common pitfalls may help to avoid misdiagnoses.

Accuracy of early rapid ultrasound in shock (RUSH) examination performed by emergency physician for diagnosis of shock etiology in critically ill patients

Background:

Rapid Ultrasound in Shock (RUSH) is a recently reported emergency ultrasound protocol designed to help clinicians better recognize distinctive shock etiologies in a short time. We tried to evaluate the accuracy of early RUSH protocol performed by emergency physicians to predict the shock type in critically ill patients.

Materials and Methods:

Our prospective study was approved by the ethics committee of trauma research center, Baqiyatallah University of Medical Science, Iran. We enrolled 52 patients with shock state in the emergency department from April 2013 to October 2013. We performed early bed-side sonographic examination for participants based on RUSH protocol. Patients received all needed standard therapeutic and diagnostic interventions without delay and were followed to document their final diagnosis. Agreement (Kappa index) of initial impression provided by RUSH with final diagnosis, and also sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of RUSH for diagnosis of each shock type were calculated.

Results:

Fifty-two patients were enrolled in our study. Kappa index was 0.7 (P value = 0.000), reflecting acceptable general agreement between initial impression and final diagnosis. For hypovolemic and obstructive shocks, the protocol had sensitivity of 100% but had lower PPV. For shocks with distributive or mixed etiology, RUSH showed PPV of 100% but had low sensitivity. For cardiogenic shocks, all reliability indices were above 90%.

Conclusion:

We highlight the role of RUSH examination in the hands of an emergency physician in making a rapid diagnosis of shock etiology, especially in ruling out obstructive, cardiogenic, and hypovolemic types.

Accuracy of Rapid Ultrasound in Shock (RUSH) Exam for Diagnosis of Shock in Critically Ill Patients

Background:

Rapid ultrasound in shock (RUSH) is the most recent emergency ultrasound protocol, designed to help clinicians better recognize distinctive shock etiologies in a shorter time frame.

Objectives:

In this study, we evaluated the accuracy of the RUSH protocol, performed by an emergency physician or radiologist, in predicting the type of shock in critical patients.

Patients and Methods:

An emergency physician or radiologist performed the RUSH protocol for all patients with shock status at the emergency department. All patients were closely followed to determine their final clinical diagnosis. The agreement between the initial impression provided by RUSH and the final diagnosis was investigated by calculating the Kappa index. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of RUSH for diagnosis of each case.

Results:

We performed RUSH on 77 patients. Kappa index was 0.71 (P Value = 0.000), reflecting acceptable general agreement between initial impression and final diagnosis. For hypovolemic, cardiogenic and obstructive shock, the protocol had an NPV above 97% yet it had a lower PPV. For shock with distributive or mixed etiology, RUSH showed a PPV of 100% but it had low sensitivity. Subgroup analysis showed a similar Kappa index for the emergency physician and radiologist (0.70 and 0.73, respectively) in performing rush.

Conclusions:

This study highlights the role of the RUSH exam performed by an emergency physician, to make a rapid and reliable diagnosis of shock etiology, especially in order to rule out obstructive, cardiogenic and hypovolemic shock types in initial exam of shock patients.

Point-of-care multiorgan ultrasonography for the evaluation of undifferentiated hypotension in the emergency department

PURPOSE

We analyzed the efficacy of a point-of-care ultrasonographic protocol, based on a focused multiorgan examination, for the diagnostic process of symptomatic, non-traumatic hypotensive patients in the emergency department.

METHODS

We prospectively enrolled 108 adult patients complaining of non-traumatic symptomatic hypotension of uncertain etiology. Patients received immediate point-of-care ultrasonography to determine cardiac function and right/left ventricle diameter rate, inferior vena cava diameter and collapsibility, pulmonary congestion, consolidations and sliding, abdominal free fluid and aortic aneurysm, and leg vein thrombosis. The organ-oriented diagnoses were combined to formulate an ultrasonographic hypothesis of the cause of hemodynamic instability. The ultrasonographic diagnosis was then compared with a final clinical diagnosis obtained by agreement of three independent expert physicians who performed a retrospective hospital chart review of each case.

RESULTS

Considering the whole population, concordance between the point-of-care ultrasonography diagnosis and the final clinical diagnosis was interpreted as good, with Cohen's k = 0.710 (95 % CI, 0.614-0.806), p < 0.0001 and raw agreement (Ra) = 0.768. By eliminating the 13 cases where the final clinical diagnosis was not agreed upon (indefinite), the concordance increased to almost perfect, with k = 0.971 (95 % CI, 0.932-1.000), p < 0.0001 and Ra = 0.978.

CONCLUSIONS

Emergency diagnostic judgments guided by point-of-care multiorgan ultrasonography in patients presenting with undifferentiated hypotension significantly agreed with a final clinical diagnosis obtained by retrospective chart review. The integration of an ultrasonographic multiorgan protocol in the diagnostic process of undifferentiated hypotension has great potential in guiding the first-line therapeutic approach.