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At least 883 records · Page 49Linked to original sources
PubMed1994

Predictors of survival for infants with congenital diaphragmatic hernia.

Over the past decade, the survival rate of infants with congenital diaphragmatic hernia (CDH) treated in the intensive care unit of the Royal Children's Hospital, Melbourne, has remained unchanged at 56% +/- 6%. Newer forms of treatment, such as extracorporeal membrane oxygenation (ECMO), high-frequency oscillation, and surfactant and nitric oxide therapy, are now available. The exact role of these therapies in the management of infants with CDH has not been determined. This study examines five clinical parameters derived from an infant's best preoperative ventilatory and blood gas data in the first 24 hours of life. One hundred twenty-five CDH infants were admitted to the intensive care unit between January 1, 1981 and December 31, 1991. Criteria for inclusion in the study were (1) CDH diagnosed within 6 hours of delivery, (2) ventilation before repair, and (3) no associated lethal congenital abnormality. Of the 90 cases studied in detail, there were 38 deaths (42% mortality rate). All five parameters were analyzed by receiver operating curve analysis to determine the optimum value of each parameter in predicting survival. An oxygenation index (MAP x FIO2/PaO2) of less than 0.08 predicted a 94% chance of survival, with a sensitivity of 96% and a specificity of 95%. Similarly, a modified ventilation index (PIP x RR x CO2/1,000) of less than 40 predicted a 91% chance of survival, with a sensitivity of 94% and a specificity of 86%. By stratifying each criterion according to outcome, three groups of infants were identified according to their response to conventional therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Hernia, Diaphragmatic↗
PubMed2006

Electrophysiologic evaluation of phrenic nerve and diaphragm function after coronary bypass surgery: prospective study of diabetes and other risk factors.

OBJECTIVE: Phrenic neuropathy after coronary artery bypass grafting has been related to various risk factors with conflicting results. The aim of this study was to assess the incidence, characteristics, and clinical consequences of phrenic neuropathy and the influence of diabetes and other risk factors. METHODS: We conducted an observational, prospective study of parallel groups including 94 consecutive patients subjected to coronary artery bypass grafting, half of them with diabetes and associated polyneuropathy. Electrophysiologic study of phrenic nerve conduction as the reference method, chest radiography, diaphragm ultrasound, and functional respiratory tests were performed 24 to 48 hours before and 7 days after surgery. In those patients showing phrenic neuropathy, explorations were repeated, including needle diaphragmatic electromyography, at 1, 3, 6, 9, 12, 18, and 24 months or until recovery. RESULTS: Fifteen of the 94 patients (16%) had phrenic neuropathy, 9 in the left side, 3 on the right, and 3 bilateral. Nine (60%) of the affected patients had diabetes, but diabetes did not represent a greater risk of neuropathy (relative risk 1.5, 95% confidence interval 0.6-3.9). Multivariate analysis showed no association of phrenic nerve injury with age, sex, ejection fraction, diabetes, use of internal thoracic artery, or number of grafts as risk factors. Phrenic neuropathy did not result in greater morbidity, and most patients recovered in less than 1 year. CONCLUSIONS: None of the risk factors studied, including diabetes, influenced the appearance of phrenic neuropathy, thus indicating a role for nerve damage during surgery. Low morbidity and relatively rapid recovery were observed.

Coronary Artery Bypass↗
PubMed2006

Gravity, the belly, and the diaphragm: you can't ignore physics.

Using a radiologic technique, the position and pattern of movement of the diaphragm have been evaluated in three adult volunteers, both awake and anesthetized, during spontaneous ventilation and with muscle paralysis and mechanical ventilation. Studies were made with the subjects in supine and left lateral decubitus positions with tidal and large-volume breaths. Positive end-expiratory pressure (PEEP) was added in studies of two subjects. During spontaneous ventilation awake or anesthetized, because of regional mechanical advantages, the dependent part of the diaphragm had the greatest displacement despite the higher intraabdominal pressure in this region. Paralysis, awake or anesthetized, caused a cephalad shift of the end-expiratory position of the diaphragm that was disproportionately large in dependent regions. It also reversed the pattern of diaphragmatic displacement. The passive diaphragm was displaced preferentially in nondependent zones where abdominal pressure is least. Consequently, PEEP could not restore the diaphragm to its awake functional residual capacity position, and large breaths also could not duplicate the pattern of displacement achieved spontaneously.

Abdomen↗
PubMed1989

Dyspnoea in chronic primary fibromyalgia.

We investigated the prevalence of dyspnoea, according to a 5-grade score proposed by the World Health Organization (WHO), among 87 consecutive women (age 44.0 +/- 8.4, range 26-65 years), with severe chronic primary fibromyalgia (CPF). In total 73 women (84%) were dyspnoeic, 47, 17, six and four patients reported dyspnoea corresponding to WHO grades 1, 2, 3 and 4, respectively. In multivariate analysis WHO dyspnoea grade was the most important determinator of exercise capacity. The higher WHO dyspnoea grade reported, the lower exercise capacity and heart rate were reached at graded bicycle exercise tests (r = -0.48, P less than 0.001 and r = -0.40, P less than 0.001). WHO dyspnoea grade correlated directly to breathing frequency at rest (r = 0.45, P less than 0.001) and inversely to maximum inspiratory pressure (r = -0.29, P less than 0.01). It did not correlate with maximum expiratory pressure, nor with spirometric measurements of pulmonary function. It is concluded that dyspnoea is common among CPF patients and is not explained by cardiac or pulmonary causes, but may partly be due to diaphragmatic muscular insufficiency and physical inactivity.

Adult↗
PubMed1986

Effects of posture and spinal bracing on respiratory function in neuromuscular disease.

Effects of posture and spinal bracing on lung function were studied in 40 children with neuromuscular disease, 20 of whom had scoliosis and were non-ambulant. Change from sitting to supine position had little effect on lung function in ambulant children, but caused a significant 12% reduction in forced vital capacity in a group of 16 non-ambulant children with scoliosis, suggesting diaphragmatic weakness in some. Spinal bracing, using a rigid supporting jacket, resulted in a significant reduction in mean vital capacity of 22%. The degree of impairment in forced vital capacity was proportional to the severity of the scoliosis (as measured by the Cobb's angle), to the amount of correction achieved by the brace, and to the degree of diaphragmatic weakness. Spinal bracing in a child with established severe scoliosis causes appreciable respiratory impairment, and this may explain why it is less likely to be tolerated than early prophylactic bracing.

Braces↗
PubMed1985

Aminophylline and its influence on ventilatory endurance in humans.

The purpose of this study was to evaluate whether the previously demonstrated improvement in contractile tension of diaphragmatic muscle with aminophylline results in improved ventilatory endurance. We measured the maximal sustained ventilatory levels during prolonged isocapnic hyperpnea as an index of ventilatory muscle function. This measurement was made in 7 normal subjects and 7 patients with chronic obstructive pulmonary disease during the intravenous administration of saline and aminophylline on 2 separate days. The order of administration of the infusions was randomized. Although both groups showed slightly higher sustained ventilatory levels during aminophylline infusion, the magnitude of change was small and unlikely to have a significant clinical benefit in the setting of respiratory muscle fatigue.

Adult↗
PubMed2004

[Megacolon imitating emphysema in the course of diaphragmatic hernia].

A 61-year old man with fever, diarrhoea, weight loss has been admitted to the hospital. Nine years earlier an air bubble in the lower part of the left lung was recognised during the chest x-ray, four years later diagnostic studies have shown a megacolon situated in the chest that significantly pressed on the flesh of the left lung and shifted the mediastinum to the right side. At that time the patient did not agree for an operation treatment. He decided for surgery in May 2002. During the operation the presence of an enormous large intestine of the megacolon type has been determined which could be found there due to diaphragm loss. The megacolon and spleen were surgically removed and the injured diaphragm was sutured. After 2 years a clinical and functional examinations of the respiratory system were performed. There was an improvement of the exercise capacity, recession of restriction in functional examinations and an increase in body mass.

Diagnosis, Differential↗
PubMed1999

Esophageal submucosal glands: structure and function.

A three-tiered defense system exists in the esophagus, which serves a dual purpose of both limiting the degree of gastroesophageal reflux and minimizing the risk of acid-induced mucosal injury. The antireflux barrier, composed of both the lower esophageal sphincter and the diaphragmatic pinchcock, is the first line of defense and serves to limit the frequency and volume of refluxed gastric contents. When the antireflux barrier fails, the second line of defense, esophageal clearance, comes into play and serves to limit the duration of contact between gastric contents and the esophageal epithelium. Mechanisms involved in esophageal clearance include gravity and esophageal peristalsis, which remove volume, and secretions from swallowed saliva and esophageal submucosal glands, which neutralize acid. The third line of defense, tissue resistance, is necessary when acid contact time is prolonged such as when esophageal clearance is either ineffective or not operative (e.g., during sleep). Most studies that have examined esophageal clearance mechanisms have focused on the roles of esophageal peristalsis and salivary secretion, but the role of submucosal gland secretions is less well understood. This article reviews the structure and function of esophageal submucosal glands and discusses the potential role of their secretory products in esophageal clearance and tissue resistance.

Animals↗
PubMed1988

[Influence of posture in respiratory function examination of obese subjects. I. In the healthy subject without ventilation disorders].

On earlier occasions healthy subjects, and chronic bronchopneumopathy patients were subjected to respiratory function tests in different postures using the plethysmographic and helium dilution methods. This protocol was then applied to a series of obese patients without the functional characteristics of alveolar hypoventilation identified in preliminary functional tests. The study revealed: a) non significant differences between plethysmographic and helium dilution findings; b) no significant volumetric differences produced by different postures (standing or squatting) especially as far as Total Lung Capacity is concerned. These results confirm the findings of others (Sharp et al., 1986) that diaphragmatic adjustment to changes in posture is inadequate in the obese even in the absence of hypoventilation.

Adult↗
PubMed1984

Regional left ventricular systolic function in patients with segmental early relaxation and normal coronary arteries.

The purpose of the study was to determine whether regional differences of left ventricular systolic function exist in patients with normal coronary arteries who manifest segmental early relaxation. The presence or absence of segmental early relaxation was determined angiographically in 16 patients with normal coronary arteries who underwent diagnostic cardiac catheterization because of chest pain. Seven patients had early relaxation localized to the left ventricular anterior wall and nine patients had no evidence of segmental early relaxation. Regional function was assessed from ventriculograms obtained in the right anterior oblique projection using the area method to calculate the regional fractional area of shortening. The fractional area of shortening of the anterolateral region was greater in patients with than in those without segmental early relaxation (69 +/- 4 versus 55 +/- 11%; p less than 0.01). In addition, in patients with segmental early relaxation, this variable exceeded the fractional area of shortening of the diaphragmatic region (69 +/- 4 versus 53 +/- 9%; p less than 0.01). There was no difference in the fractional area of shortening between these two regions in patients who did not manifest segmental early relaxation. These results suggest that regional differences in systolic function are present in patients with but not in those without segmental early relaxation. Augmented regional systolic function was observed in patients with segmental early relaxation and was limited to regions that manifested early relaxation.

Adult↗