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At least 595 records · Page 33Linked to original sources
PubMed2001

Incarcerated diaphragmatic hernia secondary to plication for eventration of diaphragm.

Diaphragmatic plication is the procedure of choice for congenital diaphragmatic eventration. In the absence of complications, most newborns with eventration do well after plication and have normal long-term respiratory functions. However complications are rare. Recurrence, ipsilateral pneumothorax and rupture of the diaphragm have been reported in literature. We report a case of incarcerated diaphragmatic hernia in a two-year-old child who had undergone plication for eventration of the diaphragm at six months of age.

Diaphragmatic Eventration↗
PubMedDate not supplied

[Gammagraphic diagnosis of diaphragmatic abnormalities in children].

Hepatic and lung scanning were evaluated as complement methods of congenital defects in the diaphragm, 14 cases were evaluated in which the scan showed alteration on the morphology and function of the liver or lung. On 13 cases correlation was found between the surgical diagnosis and the scan. In 4 cases with diaphragmatic hernia (2 Morgagni and 2 Bochdalek) the scan showed that one portion of the hepatic tissue was localized in the thoracic cavity and in one case of diaphragmatic agenesis in the scan the liver occupied the whole right hemithorax. In 9 cases of diaphragmatic eventration the scan showed alteration of the pulmonary perfussion in large or small areas and generally the hepatic image was displaced towards the thorax. These results showed that the scanning is a trustworthy method and of great help in the diagnosis of congenital diaphragmaic malformations.

Child↗
PubMed1999

Pulmonary neuroendocrine cells in nitrofen-induced diaphragmatic hernia and the effect of prenatal glucocorticoids.

The high mortality associated with congenital diaphragmatic hernia (CDH) is due to pulmonary hypoplasia and hypertension, structural and functional abnormalities which can to some extent be ameliorated by prenatal administration of glucocorticoids. In the hypoplastic, hypertensive lungs of neonatal rats in which CDH has been induced by nitrofen, those pulmonary neuroendocrine cells (PNCs) containing calcitonin gene-related peptide (CGRP) increase in number, and it has been suggested that this might be due to inhibition of secretion of the peptide, the consequent decrease in its vasodilatory effects contributing to the hypertension. Whether this increase affects the entire population of PNCs, however, and how these cells are affected by administration of prenatal glucocorticoids, is unknown. As revealed by immunolabelling for protein gene product (PGP) 9.5, a general marker of NCs and expressed per cm2 tissue section, the total PNC population in rats with nitrofen-induced CDH was significantly greater than in controls receiving only olive oil (672 vs 375/cm2, P = 0.03) and was further increased (824 per cm2) in animals treated prenatally with dexamethasone (n = 8 in all groups). The increase in the total PNC population in rats with CDH is similar in magnitude to that described for the CGRP-containing subpopulation. Since the major role of the products of PNCs is now thought to be the regulation of development of pulmonary tissues and their response to injury, it is probable that the expansion of their population in the abnormal lungs associated with CDH is an adaptive response to pulmonary maldevelopment, a response possibly augmented by exogenous corticosteroids.

Animals↗
PubMed1983

Sensitive indices of improvement in a pulmonary rehabilitation program.

It is often difficult to demonstrate objective evidence of physiologic improvement following a pulmonary rehabilitation program, despite subjective increases in exercise tolerance. In an attempt to identify sensitive indices of improvement, we studied resting and exercise lung function extensively in 15 patients (age range 45 to 73) with severe chronic obstructive lung disease before and after a pulmonary rehabilitation program. The six-week outpatient rehabilitation program consisted of exercise at 70 percent of the maximum predicted heart rate and diaphragmatic breathing for 20 minutes three times weekly. There were no significant changes in resting pulmonary function following exercise training. Exercise measurements were unchanged after completion of the program, with the exception of two parameters: heart rate and arterial lactate levels. The observed small but significant reductions in exercise heart rate and blood lactate levels following training may be due to conditioning of skeletal muscles, although respiratory muscle conditioning may be a contributing factor. Measurements of blood lactate may be a useful marker of conditioning in patients with chronic obstructive pulmonary disease who complete a pulmonary rehabilitation program.

Exercise Test↗
PubMed2000

The shrinking lungs syndrome in systemic lupus erythematosus.

A comprehensive review of the literature on shrinking lungs syndrome (SLS) in systemic lupus erythematosus involved a MEDLINE search (1965-1997) of case reports and clinical series of patients with the diagnosis of SLS. A total of 49 well-documented cases of SLS were reviewed. Shrinking lungs syndrome is characterized by unexplained dyspnea, a restrictive pattern on pulmonary function test results, and an elevated hemidiaphragm. The cause of SLS remains controversial, with several authors attributing the disorder to diaphragmatic weakness and others suggesting that chest wall restriction accounts for the clinical syndrome. No definitive therapy exists. Corticosteroids have been reported to lessen symptoms and improve pulmonary function in some patients with SLS, but other methods of treatment have occasionally been found to be helpful. Clinical presentation, method of diagnosis, pathogenesis, and treatment modalities are summarized in this review. An uncommon complication of systemic lupus erythematosus, SLS causes significant morbidity and, occasionally, mortality.

Diaphragm↗
PubMedDate not supplied

Transcutaneous oxygen monitoring in congenital diaphragmatic abnormalities.

The article considers the use of transcutaneous (Tc) partial pressure of oxygen (PO2) monitoring as an alternative form of continuous monitoring of respiratory function in paediatric critical care. The principles of TcPO2 monitoring are discussed. The relationship between TcPO2, arterial blood gases and oxygen saturation is highlighted by examining trends in TcPO2 derived in three neonates with congenital diaphragmatic abnormality. The effect of critical incidents upon TcPO2 is also explored. TcPO2 is unlikely to enhance the assessment of ventilation provided by pulse oximetry and blood gas analysis.

Blood Gas Analysis↗
PubMed1998

[Preliminary study on determination methods of respiratory muscle functions].

Attention has been paid to the research of respiratory muscle functions recently. In this paper some lung function indices concerning respiratory muscle functions, such as maximal inspiratory and expiratory pressure at mouth, inspiratory and expiratory tolerance time, transdiaphragmatic pressure and maximal transdiaphragmatic pressure and diaphragmatic electromyogram etc, were determined in 24 healthy young men and the normal values were obtained. They were important in the study of respiratory muscle functions in hard physical labours, especially in divers, pilots and sportsmen etc. These indices were also useful for evaluating convalescent therapy chronic lung diseases, respiratory muscles training programs or the drug effects on respiratory muscle fatigue etc.

Adult↗
PubMedDate not supplied

Phrenic nerve block caused by interscalene brachial plexus block: effects of digital pressure and a low volume of local anesthetic.

BACKGROUND AND OBJECTIVES: Interscalene brachial plexus block (ISB) is associated with phrenic block and diaphragmatic paralysis when high volumes (40-50 mL) of local anesthetic are injected. The goal of our study was to test if a low volume of local anesthetic administered while maintaining proximal digital pressure might more selectively block the brachial plexus and decrease the frequency of phrenic nerve block. METHODS: Twenty healthy patients undergoing ISB for orthopedic surgery of the upper extremity were randomly allocated to receive either 20 mL 1.5% mepivacaine while proximal digital pressure to the site of puncture was performed, or 40 mL 1.5% mepivacaine without digital pressure. Spirometry and clinical data were evaluated at baseline, 10, and 90 minutes after accomplishing the block and after the motor and sensory block resolved. Diaphragmatic excursion during deep inspiration was also evaluated 90 minutes after the block was performed, with the patient in the sitting position. RESULTS: Interscalene brachial plexus block produced diaphragmatic paralysis in all patients included in the study, as demonstrated by the pulmonary function testing and the chest radiograph. No significant differences were found in any of the parameters studied. At 10 minutes, baseline functional residual capacity had diminished by 34 +/- 10% in the 40 mL group and 37 +/- 13% in the 20 mL group. Maximum cephalad sensory dermatome level was also similar in both groups, being C 3 or above in all patients. Ipsilateral hemidiaphragmatic motion was similar in both groups (3.2 +/- 2.3 cm in the 40 mL group and 2.6 +/- 1.7 cm in the 20 mL group). However, in no case was dyspnea manifested. CONCLUSIONS: Decreasing the volume of local anesthetic and applying proximal digital pressure to the site of injection is not effective in reducing the cervical block spread and the frequency or intensity of diaphragmatic paralysis during interscalene ISB.

Adult↗
PubMed1990

Phrenic afferents and ventilatory control.

It has been understood since the late 1800s that the diaphragm has significant sensory innervation. The role of phrenic afferents in the control of breathing, however, has been obscure. The phrenic nerve has been shown to contain a full array of afferent fibers. However, proprioceptive (group 1 fibers) afferents are few compared to postural muscles or the intercostals. The diaphragm, unlike the inspiratory intercostal muscles, has a small complement of spindle afferents and not all of these spindles are supplied with fusorial fibers. Reduced spindle afferents under gamma control help to explain previous studies of the diaphragm that have failed to reveal autogenic facilitation, that is, a reflex-mediated increase in drive during inspiratory loading. Nevertheless, some clinical studies have revealed increased activation of the diaphragm when its length is reduced. Group 1 fibers, which are predominantly tendon organ afferents in the diaphragm, have been shown to have a phasic inhibitory function. A reduction in this inhibition brought about by a reduction in diaphragmatic length during lung inflation may explain the increased diaphragmatic activation reported in clinical studies. Phrenic afferents have been shown to have multiple spinal and supraspinal projections. Recent studies have explored the ventilatory effects of thin fiber afferents (group III and IV fibers) in the phrenic nerve. Stimulation of these afferents has been shown both to inhibit and excite ventilation. These afferents arise from polymodal receptors that respond to both mechanical and chemical stimulation. Activation of these receptors may occur in a variety of conditions and the ventilatory response may be determined by the specific receptor activated.

Animals↗
PubMed2003

Does V-A ECMO increase the likelihood of chylothorax after congenital diaphragmatic hernia repair?

BACKGROUND: The authors noticed a relatively large number of patients with congenital diaphragmatic hernia (CDH) repair after extracorporeal membrane oxygenation (ECMO) who had a chylothorax (CT). The data are reviewed. METHODS: The charts of patients from 1990 until 2000 with CDH, treated with or without ECMO, together with the charts of patients treated with ECMO for other reasons and patients with esophageal atresia (EA) repair were reviewed. The diagnosis of CT was made if aspirated fluid appeared chylous and contained more than 90% lymphocytes or if the triglyceride level was more than 1.50 mmol/L. RESULTS: Eighty-nine patients with CDH were analyzed. Postoperatively, 10% had a CT-21% in CDH patients with ECMO treatment and 6% in CDH patients without ECMO treatment. This difference appeared to be significant (P <.05). The presence of a patch as independent variable for the development of CT also showed significance (P <.05). CONCLUSIONS: Chylothorax presented in almost all cases as a left-sided fluid accumulation, and a patch was present in the majority of patients with CDH. Therefore, CT should be considered the result of the severity of the defect rather than the consequence of ECMO as a therapeutic modality.

Artificial Organs↗
PubMed1979

The effect of overdistention of the lung on pulmonary function in beagle puppies.

The removal of one lung from a beagle puppy results in minimal interference with lung function or the arterial gases. The removal of air from the empty pleural cavity results in a shift of the mediastinum and overdistention of the contralateral lung. An immediate decrease in the PO2 and increase in the PCO2 is seen. Significant increase in the alveolar-arterial CO2 gradient reflected marked increase in dead space ventilation. Biopsies of the overdistended lung demonstrated emphysema and disruption of alveoli. These changes may explain some of the deterioration of lung function and the complication of contralateral pneumothorax following repair of a Bochdalek diaphragmatic hernia. Our study suggests that the mediastinum should be stabilized in the midline after repair of a diaphragmatic hernia or after a pneumonectomy in an infant or small child.

Animals↗
PubMed1992

An unusual cause of bilateral diaphragmatic paralysis.

In a patient who had a sudden onset of bilateral diaphragmatic paralysis after forceful neck manipulation complete, though gradual, recovery in lung function and transdiaphragmatic pressures was seen over three years. This is a previously unrecognised risk of neck osteopathy.

Aged↗
PubMed1982

Effect of pressure and timing of contraction on human diaphragm fatigue.

The relationship between the mean transdiaphragmatic pressure swing developed with each inspiration (Pdi) and the fraction of the breathing cycle time spent in inspiration (TI/Ttot) (Pdi X TI/Ttot) was related to the maximal time that such a run could be sustained (Tlim). Four normal subjects breathed with a constant breathing pattern for 45 min or until Pdi could no longer be sustained, whichever came first. The breathing patterns included Pdi of 0.15-0.90 of Pdimax and TI/Ttot of 0.15-1.0. Pdi was obtained by adjusting an inspiratory resistance, and the timing by monitoring tidal volume with time base from an oscilloscope. The Tlim of a run was found to be inversely related to both Pdi and TI/Ttot and hence inversely related to their product, following a quadratic hyperbole function. Pdi X TI/Ttot represents an index of the tension time of the diaphragm (TTdi). The breathing pattern that could be sustained more than 45 min was found to have a TTdi of about 0.15, which was termed critical TTdi. Above that value Tlim decreased as a function of TTdi. The results are consistent with Tlim being related to diaphragmatic blood flow limitation.

Diaphragm↗
PubMed1996

Peripheral and respiratory muscles in chronic heart failure.

It is well-established that in patients with congestive heart failure (CHF), exercise is limited by fatigue and shortness of breath. The poor correlation between the fatigue and indices of central haemodynamic function might indicate that peripheral muscle alterations contribute to impaired exercise capacity. Intrinsic abnormalities of the skeletal muscles have been suggested as a possible explanation. Since the shortness of breath correlates poorly with changes in lung function, changes in the respiratory muscles have been investigated. Studies have demonstrated diaphragmatic myopathy and atrophy similar, in part, to the changes in peripheral skeletal muscles. In CHF, type I (slow twitch) fibre atrophy is seen in respiratory as well as in peripheral muscles. The mechanism of these alterations remains to be elucidated. Studies into the mechanism of muscle dysfunction in congestive heart failure are relevant to the prospect of treatment of the changes in peripheral and respiratory muscles.

Atrophy↗
PubMed1984

Electrophysiologic evaluation of diaphragm by transcutaneous phrenic nerve stimulation.

Phrenic nerve function was evaluated by transcutaneous stimulation in the neck and recording the diaphragmatic potential from surface electrodes placed at the ipsilateral seventh intercostal space (7CS) and the xiphoid process (XP). Simultaneous recordings from 7CS and XP electrodes connected together (XP-7CS) and each connected to a remote reference (knee-7CS and knee-XP) disclosed that the 7CS electrode was always more active and showed electropositive activity, whereas the XP electrode, which was only minimally active, showed electronegative response. Out-of-phase summation of opposite polarity activity at the two electrodes resulted in a higher amplitude response in XP-7CS derivation. Phrenic nerve studies are useful in establishing phrenic nerve injury following cardiothoracic operation. They may also provide evidence of phrenic nerve or diaphragmatic involvement in demyelinative neuropathies, motor neuron disease, and muscular dystrophies.

Adult↗
PubMed1994

[Improvement of post-operative activities of daily living in an aged patient with vanishing lung].

A 71-year-old male was admitted to our hospital due to progressive dyspnea. The right lung of this patient was replaced by multiple bulous lesions including giant bullae. He had severe deterioration of lung function and gas exchange. He did not complete the pre-operative examinations for thoracic surgery, but improvement in ventilatory function was expected after bullectomy. After multiple bullectomy, this case showed marked improvements in lung function and gas exchange, subsequently his dyspnea improved, as did his activities of daily living. These lung functional improvement may have resulted not only from the mechanical advantage of diaphragmatic motion due to removal of space-occupying lesion of the lung, but also from the reduction of tough fibrous adhesion between the lung and the parietal pleura which had impaired smooth lung movement. Thorough evaluation of operative indications in necessary before surgery in aged patients with lung diseases.

Activities of Daily Living↗