Comparison of the cardiovascular effects of isoflurane and sevoflurane as measured by magnetic resonance imaging in children with congenital heart disease

Natural History of Cardiomyopathy in Adult Dogs With Golden Retriever Muscular Dystrophy

Background

Duchenne muscular dystrophy (DMD) is an X‐linked disease that causes progressive muscle weakness. Affected boys typically die from respiratory or cardiac failure. Golden retriever muscular dystrophy (GRMD) is genetically homologous with DMD and causes analogous skeletal and cardiac muscle disease. Previous studies have detailed features of GRMD cardiomyopathy in mostly young dogs. Cardiac disease is not well characterized in adult GRMD dogs, and cardiac magnetic resonance (CMR) imaging studies have not been completed.

Methods and Results

We evaluated echocardiography and CMR in 24 adult GRMD dogs at different ages. Left ventricular systolic and diastolic functions, wall thickness, and myocardial strain were assessed with echocardiography. Features evaluated with CMR included left ventricular function, chamber size, myocardial mass, and late gadolinium enhancement. Our results largely paralleled those of DMD cardiomyopathy. Ejection fraction and fractional shortening correlated well with age, with systolic dysfunction occurring at ≈30 to 45 months. Circumferential strain was more sensitive than ejection fraction in early disease detection. Evidence of left ventricular chamber dilatation provided proof of dilated cardiomyopathy. Late gadolinium enhancement imaging showed DMD‐like left ventricular lateral wall lesions and earlier involvement of the anterior septum. Multiple functional indexes were graded objectively and added, with and without late gadolinium enhancement, to give cardiac and cardiomyopathy scores of disease severity. Consistent with DMD, there was parallel skeletal muscle involvement, as tibiotarsal joint flexion torque declined in tandem with cardiac function.

Conclusions

This study established parallels of progressive cardiomyopathy between dystrophic dogs and boys, further validating GRMD as a model of DMD cardiac disease.

PRESSÃO INTRAOCULAR, PRESSÃO ARTERIAL MÉDIA E DIÂMETRO PUPILAR EM COELHOS ( (Oryctolagus cuniculus) ) SUBMETIDOS AO BLOQUEIO RETROBULBAR COM DIFERENTES PROTOCOLOS ANESTÉSICOS

Resumo O objetivo deste estudo foi buscar novos protocolos de anestesia loco regional para procedimentos oftálmicos que proporcionem segurança e manutenção das funções vitais, além de manter a pressão intraocular estável, com centralização do bulbo do olho e acinesia palpebral. Foram utilizados 20 coelhos da raça Nova Zelândia para a realização de quatro protocolos de anestesia local através do bloqueio retrobulbar com lidocaína 2% com vasoconstritor, lidocaína 2% sem vasoconstritor associada ao tramadol, ropivacaína 1% e bupivacaína 0,5%, cada animal recebeu o volume anestésico de 1,0 mL. Todos os protocolos anestésicos utilizados promoveram acinesia palpebral e centralização do bulbo do olho durante todo o período de avaliação. A realização do bloqueio retrobulbar com os protocolos anestésicos demonstrou ser factível e segura quanto à manutenção da pressão intraocular, pressão arterial invasiva e diâmetro pupilar e pode ser utilizada para realização de cirurgias intraoculares. Os anestésicos proporcionaram bom bloqueio retrobulbar, entretanto a bupivacaína foi o anestésico que ocasionou o maior diâmetro pupilar comparativamente aos demais fármacos testados.

ABCs of Neonatal Cardiac Anesthesia

Congenital heart disease (CHD) is relatively common and there are treatment options for virtually every form of CHD. With good care, the majority of babies can survive to adulthood; however, CHD remains a significant cause of death in infancy and neonates are especially vulnerable. In order to manage these patients, a clear understanding of the underlying pathophysiology and the planned surgical procedure is important. However, attention to detail and meticulous care are equally important, and, in addition, there are several management strategies that may standardize practice and can improve outcome.

Evaluation of sevoflurane as an anesthetic agent for voiding cystourethrography in pediatric patients

BACKGROUND

Sevoflurane anesthetic has recently been administered by anesthesiologists during voiding cystourethrograms in a centre where radiologists are not permitted to deliver pediatric sedation.

OBJECTIVE

To determine whether sevoflurane is a satisfactory anesthetic agent for voiding cystourethrography in children.

METHODS

Records of children undergoing voiding cystourethrogram while they were under sevoflurane were reviewed for anesthetic adverse effects and diagnostic quality of the cystourethrogram. The occurrence of on-table voiding and post-void residual bladder volume were documented and compared with an age- and sex-matched control group of children undergoing unsedated voiding cystourethrography. The caregivers were surveyed regarding the anesthetic experience.

RESULTS

A total of 91 children underwent sevoflurane voiding cystourethrography; there were no adverse cardiorespiratory events. Voiding was observed in 96%, with residual bladder volumes minimal in 38%, moderate in 32%, and large in 28% of anesthetized children, not significantly different from the control group. Vesicoureteral reflux was observed in 53% of examinations under sevoflurane. When children with a previous history of reflux or voiding cystourethrography were excluded in a comparison with age- and sex-matched controls, vesicoureteral reflux was observed in 38% of studies under sevoflurane and in 44% of studies in the control group, P = .69; 85% of caregivers of children with prior unsedated voiding cystourethrography found voiding cystourethrography with sevoflurane easier than without sevoflurane; 89% thought the anesthetic experience reduced their child's anxiety towards medical procedures.

CONCLUSION

No adverse events or effects on diagnostic quality of the pediatric voiding cystourethrogram were encountered when using sevoflurane. The majority of surveyed caregivers thought that anesthesia made voiding cystourethrography an easier experience for their child.

Influence of genetic background on ex vivo and in vivo cardiac function in several commonly used inbred mouse strains

Inbred mouse strains play a critical role in biomedical research. Genetic homogeneity within inbred strains and their general amenability to genetic manipulation have made them an ideal resource for dissecting the physiological function(s) of individual genes. However, the inbreeding that makes inbred mice so useful also results in genetic divergence between them. This genetic divergence is often unaccounted for but may be a confounding factor when comparing studies that have utilized distinct inbred strains. Here, we compared the cardiac function of C57BL/6J mice to seven other commonly used inbred mouse strains: FVB/NJ, DBA/2J, C3H/HeJ, BALB/cJ, 129X1/SvJ, C57BL/10SnJ, and 129S1/SvImJ. The assays used to compare cardiac function were the ex vivo isolated Langendorff heart preparation and in vivo real-time hemodynamic analysis using conductance micromanometry. We report significant strain-dependent differences in cardiac function between C57BL/6J and other commonly used inbred strains. C57BL/6J maintained better cardiac function than most inbred strains after ex vivo ischemia, particularly compared with 129S1/SvImJ, 129X1/SvJ, and C57BL/10SnJ strains. However, during in vivo acute hypoxia 129X1/SvJ and 129S1/SvImJ maintained relatively normal cardiac function, whereas C57BL/6J animals showed dramatic cardiac decompensation. Additionally, C3H/HeJ showed rapid and marked cardiac decompensation in response to esmolol infusion compared with effects of other strains. These findings demonstrate the complex effects of genetic divergence between inbred strains on cardiac function. These results may help inform analysis of gene ablation or transgenic studies and further demonstrate specific quantitative traits that could be useful in discovery of genetic modifiers relevant to cardiac health and disease.