Doppler echocardiography in stress testing

Doppler ultrasound may have a role in the stress testing laboratory for the identification of patients with coronary disease through the assessment of dynamic ventricular systolic function. Quantitative systolic ejection phase indexes of maximal acceleration, peak velocity, and volume of blood ejected from the left ventricle can be obtained in the exercising patient. Trials comparing stress Doppler ultrasound with ST-segment changes, gated blood pool radionuclide or echocardiographic studies of ejection fraction or wall motion abnormality, and thallium scintigraphic perfusion defects have returned comparable or better sensitivity and specificity referencing coronary angiography. Graded treadmill exercise, stationary bicycle exercise, and pharmacological stress (dipyridamole) have been used. The normal Doppler stress response is a near linear increase in peak ejection velocity with increasing cardiac work, as reflected in heart rate. Patients with coronary artery disease show blunted augmentation of Doppler ejection dynamics between rest and peak stress, and the degree of blunting appears to be proportional to the anatomic extent of coronary disease and the magnitude of ventricular perfusion and performance impairment. Stress Doppler ultrasound achieves diagnostic power for coronary disease with ultrasonic technology, inexpensive equipment, without ionizing radiation, and few personnel.     

Prevalence of viral respiratory tract infections in children with asthma

BACKGROUND: Previous studies support a strong association between viral respiratory tract infections and asthma exacerbations. The effect of newly discovered viruses on asthma control is less well defined. OBJECTIVE: We sought to determine the contribution of respiratory viruses to asthma exacerbations in children with a panel of PCR assays for common and newly discovered respiratory viruses. METHODS: Respiratory specimens from children aged 2 to 17 years with asthma exacerbations (case patients, n = 65) and with well-controlled asthma (control subjects, n = 77), frequency matched by age and season of enrollment, were tested for rhinoviruses, enteroviruses, respiratory syncytial virus, human metapneumovirus, coronaviruses 229E and OC43, parainfluenza viruses 1 to 3, influenza viruses, adenoviruses, and human bocavirus. RESULTS: Infection with respiratory viruses was associated with asthma exacerbations (63.1% in case patients vs 23.4% in control subjects; odds ratio, 5.6; 95% CI, 2.7- 11.6). Rhinovirus was by far the most prevalent virus (60% among case patients vs 18.2% among control subjects) and the only virus significantly associated with exacerbations (odds ratio, 6.8; 95% CI, 3.2-14.5). However, in children without clinically manifested viral respiratory tract illness, the prevalence of rhinovirus infection was similar in case patients (29.2%) versus control subjects (23.4%, P > .05). Other viruses detected included human metapneumovirus (4.6% in patients with acute asthma vs 2.6% in control subjects), enteroviruses (4.6% vs 0%), coronavirus 229E (0% vs 1.3%), and respiratory syncytial virus (1.5% vs 0%). CONCLUSION: Symptomatic rhinovirus infections are an important contributor to asthma exacerbations in children. CLINICAL IMPLICATIONS: These results support the need for therapies effective against rhinovirus as a means to decrease asthma exacerbations.     

Staff knowledge,attitudes and practices regarding glycaemic management in adult intensive care units: A national survey

Background

Hyperglycaemia is common in critically ill adult patients. Many studies have identified the content, methods, and effects of glycaemic control but have not explored the effects of knowledge, attitudes, and practices (KAP) on glycaemic control in critically ill adults. Various factors also influence the KAP of intensive care unit (ICU) staff.

Aims

To assess KAP regarding glucose management for critically ill adults among nurses and medical professionals and identify the factors that influence their KAP in ICUs.

Methods

A multicentre cross-sectional survey.

Results

In total, 403/459 (response rate: 87.8%) participants from ICUs in nine tertiary hospitals in China participated in this study, 82.4% of whom were female and 93.4% of whom were nurses. The mean work experience was 8.88 years, and the mean critical care experience was 6.59 years. The scoring rate for the three dimensions of knowledge, attitudes, and practices were 82.35%, 87.69%, and 76%, respectively. We did not find any other factors affecting the KAP scores except for the level of knowledge awareness (p < 0.001), awareness of the importance (p < 0.001), and training for glucose control (p = 0.004).

Conclusion

ICU staff KAP regarding glycaemic control in critically ill adults among ICU professionals were acceptable in China. However, ICU professionals' current knowledge regarding nutrition, glucose variability, and skills related to glucose management could be improved.

Relevance to Clinical Practice

ICU educators should provide more skills-related training for healthcare professionals in the glycaemic management of critically ill adults. Moreover, the process of managing blood glucose in adult ICU patients is a collaborative, multidisciplinary team effort, with monitoring and feedback required during implementation.     

Elimination of Laparoscopic Lens Fogging Using Directional Flow of CO2

Background and Objectives:

Surgeons constantly struggle with the formation of condensation on the lens of a laparoscope, which prolongs procedures and reduces visibility of the abdominal cavity. The goal of this project was to build a device that would direct a flow of carbon dioxide (CO₂) into an open chamber surrounding the lens of a laparoscope, acting to keep moisture away from the lens and eliminate condensation.

Methods:

The device isolates the lens of the laparoscope from the humid environment of the intraperitoneal cavity by creating a microenvironment of dry CO₂. This was accomplished by building a communicating sleeve that created an open chamber around the distal 2 to 3 cm of the scope. Into this cavity, dry cool CO₂ was pumped in from an insufflator so that the path of the gas would surround the lens of the scope and escape through a single outlet location through which the scope views the intraperitoneal cavity. This chamber is proposed to isolate the lens with a high percentage of dry CO₂ and low humidity. The device was tested in 7 different adverse conditions that were meant to challenge the ability of the device to maintain the viewing field with no perceptible obstruction.

Results:

In all of the conditions tested, 25 trials total, the device successfully prevented and/or eliminated laparoscopic lens fogging.

Conclusions:

The device designed for this project points to the potential of a simple and effective mechanical method for eliminating laparoscopic lens fogging.     

Three-dimensional speckle-tracking echocardiography for evaluating myocardial motion in patients with cardiorenal syndrome

Because of better awareness and understanding of its pathophysiology, the cardiorenal syndrome (CRS) is more often diagnosed and better managed. The echocardiographic evaluation of CRS now benefits from three-dimensional speckle tracking echocardiography (3D-STE), which allows multidimensional and real-time evaluation of regional myocardial and overall cardiac function, and helps assessing the degree of myocardial damage. This article describes the application of 3D-STE in evaluating the myocardial motion in patients with CRS.     

Preferential loss of maternal 9p alleles in childhood acute lymphoblastic leukemia.

Germ-line events, such as paternal mutation or genomic imprinting, contribute to the early onset of childhood cancers such as retinoblastoma, Wilms tumors, and neuroblastoma. Given the high frequency of deletion involving chromosome 9p in childhood acute lymphoblastic leukemia (ALL), this study investigated whether 9p deletion might reflect preexisting germ-line gene inactivation. To do this the parental origin of deletion was determined in 10 cases of ALL with 9p21 loss of heterozygosity. Of these cases, 9 showed loss of the maternally derived allele, suggesting that a germ-line event involving a 9p gene may play a role in the onset of childhood ALL.