Standardization of Sonographic Diaphragm Thickness Evaluations in Healthy Volunteers.

BACKGROUND: B-mode ultrasound can be used to measure diaphragm thickness at the zone of apposition. We believe it is necessary to develop normal values for diaphragm thickness at rest in a large group of healthy subjects and compare them with international results. METHODS: Ultrasound measurements of diaphragm thickness at expiratory rest were taken in 109 healthy individuals, with results stratified by sex, body mass index, and thorax circumference. The following methods were used for analysis and interpretation. Multivariable databases with descriptive statistical analyses were made. The Pearson chi-square test was used to evaluate the distribution between variables. Additionally, mean and SD values were calculated. For standardization, the data were separated by sex within a 95% CI, and we calculated a Z test. A 95% CI was also constructed for proportion analyses. RESULTS: One hundred nine healthy volunteers were included in the study, and the correlation between the body mass index and thorax circumference values with a Pearson chi-square test resulted in an r = 0.69. Additionally, the average value of diaphragmatic thickness was 0.19 ± 0.04 cm (95% CI 0.17-0.20 cm) for men and 0.14 ± 0.03 cm (95% CI 0.13-0.15 cm) for women (P = .001). There was no relation between body mass index thorax circumference, and diaphragmatic thickness. CONCLUSION: Real-time ultrasound of the diaphragm is a simple, inexpensive, and portable imaging technique that can provide qualitative anatomical information. The findings in this study show that sonographic diaphragm evaluations can be applied to the general population.

Especies reactivas de oxígeno, sepsis y teoría metabólica del choque séptico / Reactive oxygen species, sepsis and metabolic theory of the septic shock

Resumen La sepsis es una de las principales causas de mortalidad en la unidad de terapia intensiva. El término especies reactivas de oxígeno (ERO) incluye moléculas con un electrón impar, llamadas radicales libres, como el anión superóxido, y también agentes oxidados como el peróxido de hidrógeno. Las ERO pueden reaccionar con muchas moléculas y pueden producir un daño no controlado; sin embargo, también tienen un papel fundamental en el metabolismo celular. El estrés oxidante es el resultado de la respuesta inflamatoria asociada a la sepsis que produce cambios en la función mitocondrial y en la microcirculación. El objetivo de este trabajo es revisar el papel de las ERO en sepsis y nuevos conceptos relacionados con la teoría metabólica del choque séptico.

Abstract Sepsis remains the most common cause of death in the intensive care unit. The term Reactive Oxygen Species (ROS) includes molecules with an unpaired electron, called free radicals, such as superoxide anion, and also oxidant agents such as hydrogen peroxide. ROS can react with several molecules and induce an uncontrolled damage in a variety of biomolecules. On the other hand, ROS have essential roles in cell function. Marked oxidative stress as a result of the inflammatory responses inherent with sepsis initiates changes in mitochondrial function and microcirculation. The aim of this paper is to review the roll of ROS in sepsis and new concepts related to the metabolic theory of septic shock.

Efectos fisiológicos en un ambiente de microgravedad / Physiological effects in an environment of microgravity

Resumen En el siglo veinte, el estudio del universo y el desarrollo de los vuelos espaciales fueron posibles gracias al avance tecnológico de naves de propulsión por diferentes tipos de cohetes. Muchos sistemas biológicos se afectan en los vuelos espaciales y se ha demostrado que en un ambiente de microgravedad se altera de manera significativa la función musculoesquelética, neurosensitiva, endócrina, renal, respiratoria y cardiovascular, además del riesgo de lesión debido a la exposición a diferentes tipos de radiación, eventos que comprometen la salud y rendimiento de los astronautas. Por lo anterior es fundamental mantener la salud y acondicionamiento físico de los astronautas durante el vuelo espacial para facilitar y acelerar su recuperación al llegar a la tierra.

Abstract Until the twentieth century, study about the universe and speculation about the nature of spaceflight were no closely related to the technical developments that led to rocket propulsión. Many biological systems are adversely affected by space flight and It has been shown that exposure to microgravity can alter the musculoskeletal, neurosensory, endocrine, renal, respiratory and cardiovascular systems and the risk of injury due to radiation exposure resulting in deconditioning that may compromise astronauts health and performance. Maintainig health and fitness during space missions is critical for preserving performance during misión specific tasks and to optimize terrestrial recovery.

[Ultrasonographic evaluation of the diameter of the optic nerve sheath for medication of intracranial pressure: a case report]. / Evaluación ultrasonográfica del diámetro de la vaina del nervio óptico (DVNO) para la medición de la presión intracraneana (PIC): a propósito de un caso.

The main complication associated with acute brain injury is the elevation of intracranial pressure (ICP) and it is associated with high morbidity and mortality. In these patients, multimodal neurological monitoring has emerged as a fundamental tool in the intensive care unit, with the minimally invasive trend seen in recent years. We report the case of a patient in which ICP monitoring was based on the measurement of the diameter of the optic nerve sheath (DONS), a procedure that has shown a good correlation with the ICP, as well as a high specificity, sensitivity, and low cost.