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At least 1,135 records · Page 63Linked to original sources
PubMed1997

Video laparoscopy for the treatment of bleeding esophageal varices.

Bleeding from esophageal varices is the major cause of death in patients with portal hypertension. The ideal surgical procedure should effectively control bleeding, with as little impairment of liver function as possible and with low rates of encephalopathy. Based on this objective, we propose the azygoportal disconnection (APD) with splenic artery ligation, and suturing of the gastric and esophageal varies without opening the esophagus, by video laparoscopy. With the patient placed in a semigynecologic position, we use five trocars, and the intervention begins by dissection of the diaphragmatic hiatus and isolation of the esophagus. Then devascularization of the gastric fundus is accomplished. After that, dissection and ligature between clips of the splenic artery are performed. The surgery proceeds with dissection and ligation of the vessels of the lesser curvature. After orally introducing a 12-mm Fouchet probe, we suture the varices of the distal esophagus transmurally, with interrupted sutures. The procedure is accomplished with a floppy Nissen valve. Between March 1994 and May 1995, four patients were treated with this method, two men and two women with a mean age of 54 years. All of them had hepatic cirrhosis. Three patients were classified Child B and the other Child C. Surgical indication in all subjects was persistent bleeding of the esophageal varices, after failure of such clinical attempts as endoscopic sclerosis and tamponade with the Sangstaken-Blakemore balloon. The operation mean time was 177 min. Neither bleeding nor hemodynamic changes occurred during the surgery. The patients were sent to the intensive care unit (ICU) postoperatively for a mean time of 3 days, and they were discharged from the hospital between days 8 and 10. The evolution demonstrated stabilization of the hepatic function and regression of the varices from grades III and IV to grade I. No bleeding recurred. Although this study had a small number of patients, we believe that this operation made by mini-invasive technique permits a quick recovery, reducing the global morbidity of this procedure.

Adult↗
PubMed1990

Action and interaction of respiratory muscles in dogs.

How the respiratory muscles, the so-called "vital pump", works is relevant to medicine and nevertheless, poorly understood. The present studies attempt to obtain a better insight in the action and interaction of respiratory muscles by measuring the mechanical outcome of individual respiratory muscle contraction with two different techniques in anesthetized dogs. First, we measured the changes in length undergone by respiratory muscles using sonomicrometry. We observed that the costal and crural parts of the diaphragm frequently behaved differently, supporting the concept that these two parts behave as two different muscles. Moreover, crural diaphragmatic length appeared to be linked to abdominal dimensions, the classical used estimate of diaphragmatic length, whereas costal diaphragmatic length was not. The parasternal or the interchondral parts of the internal intercostals invariably shortened with inspiration supporting their role as inspiratory agonists. By way of contrast, the respiratory length changes in the external and interosseus internal intercostal were variable and not consistently in different directions for the two layers. The changes in length, during rotation of the trunk were consistent, larger and systematically in opposite directions for these two layers, suggesting that these muscles predominantly function as rotators of the trunk or at least that a role in rotation of the trunk explains better the need for two layers of intercostal muscles with different fiber orientation than a respiratory role. Second, we measured changes in intramuscular pressure in the costal and crural parts of the diaphragm, and in the parasternal intercostals, using mini-transducers. In the diaphragm intramuscular pressure appeared to be a complex variable determined by the tension developed by the muscle as well as the pleural and abdominal pressures applied to the muscle. As a consequence, intramuscular pressure often decreased during contraction, suggesting that in contrast to other muscles, diaphragmatic contraction may enhance diaphragmatic blood flow. Conversely, in the parasternal intercostals, intramuscular pressure invariably increased during contraction, and a linear relationship between intramuscular pressure and contractile force was present. The forces developed by these muscles during quiet breathing and other respiratory maneuvers were found to be significant, supporting the important inspiratory role of the parasternal intercostals. Intramuscular pressure thus appeared to be a perfect estimate of the force developed by these muscles. Finally, we examined the changes in respiratory muscle interaction with hyperinflation.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1982

Function of the future respiratory system in the growth retarded fetal sheep.

The development of the future air breathing respiratory system was investigated in eight carunclectomised fetal sheep and five control fetal animals over the last third of gestation (approximately day 100-day 145). Carunclectomy resulted in the test fetal animals being hypoxaemic, hypercapnic, hypoglycaemic and acidotic. All fetal animals were chronically instrumented with diaphragmatic electromyographic leads, fetal jugular vein and carotid artery catheters, an amniotic fluid catheter and small electrocardiographic leads placed on the chest wall. There was evidence of a significant, but small, reduced relative lung size in the carunclectomised animals by day 140 without corresponding relative changes in the weight of the brain, liver, or heart. Diaphragmatic electromyograph (EMG) was analysed in detail over the last third of gestation. In both groups of animals, the normal reduction in fetal 'breathing' rate, and the normal increase in fetal apnoea was noted with increasing periods of diaphragmatic silence as fetal apnoea was noted with increasing periods of diaphragmatic silence as gestation advanced. Linear regression analyses revealed that fetal breathing rate was significantly reduced over the last third of gestation, whilst fetal apnoea significantly increased in the carunclectomised animals. Average total integrated diaphragmatic activity was reduced prior to 120 days. This reduction was evident in the strength of each diaphragmatic contraction before 110 days. In three test and three control animals, histochemical analyses were undertaken to fibre type the muscles of the diaphragm. Fatigue resistant fibres were significantly reduced in the carunclectomised fetuses, and fibre diameters were diminished. Centroid analyses of the power spectrum of the diaphragmatic EMG did not however support the concept of increased muscle fatigue in the test animals.

Animals↗
PubMed1995

Right latissimus dorsi cardiomyoplasty in diaphragm eventration and cardiac malposition.

Cardiomyoplasty recently has been introduced as a surgical therapy for long-lasting cardiac dysfunction in selected patients. We report the case of a patient affected by chronic heart failure, unresponsive to maximal medical therapy, with concomitant posttraumatic injury of the left phrenic nerve, left diaphragm eventration, and cardiac malposition (right displacement). In view of the progressive deterioration of the cardiac function, cardiomyoplasty was recommended, and the right latissimus dorsi muscle was used to perform the wrapping procedure. A 6-month follow-up showed significant functional, as well as hemodynamic, improvements in addition to a reduction in medical therapy.

Cardiomyopathy, Dilated↗
PubMed2000

Reversibility of paraneoplastic bilateral diaphragmatic paralysis after nephrectomy for renal cell carcinoma.

Bilateral diaphragmatic paralysis is usually caused by anatomic lesions of both phrenic nerves (e.g., after cardiothoracic surgery), generalized neurologic diseases (e.g., primary motor neuron disease, amyotrophic lateral sclerosis) or is without a known cause (idiopathic). We report a case of a patient with renal cell carcinoma complicated by an isolated bilateral diaphragmatic paralysis without clinical or electromyographic signs of other muscle or nerve involvement. There has been progressive, though till now partial, recovery of his vital capacity rising from 44% to 72% of predicted values, and maximal inspiratory pressures during the two years following the curative resection of his renal cell carcinoma. We believe this is the first report of a paraneoplastic bilateral diaphragmatic paralysis with actual recovery after tumour therapy.

Carcinoma, Renal Cell↗
PubMed2002

Laryngeal muscle activities with cerebral hypoxia-ischemia in newborn lambs.

This study tested the hypotheses that (1) acute cerebral hypoxia-ischemia changes laryngeal adductor, laryngeal abductor, and diaphragmatic activities, resulting in central apnea with laryngeal closure; and (2) these laryngeal muscle activities act to maintain absolute lung volume. The respiratory pattern was determined in three asphyxiated, awake preterm lambs after cesarean section birth and in 12 awake, term lambs, with normal lung function, after induction of acute cerebral hypoxia-ischemia by occlusion of the brachiocephalic artery. Electrocorticogram activity, flow, volume, electromyograms of laryngeal abductor and adductor muscles and diaphragm, and, in the term lambs, trans-upper airway pressure and carotid blood flow were recorded. With either preterm birth asphyxia or induced acute cerebral hypoxia-ischemia, minute ventilation initially increased, and then hypopnea occurred. During the hypopnea, laryngeal adductor activity was prominent, accompanied by an increased upper airway pressure and a maintained/raised absolute lung volume. Thus, when acute hypoxia-ischemia limited to the upper body is induced in lambs with normal lung function, expiratory laryngeal adduction with closure of the upper airway occurs and likely functions to aid autoresuscitation.

Animals↗
PubMedDate not supplied

Pulmonary gastrin-releasing peptide expression in anencephaly.

Gastrin-releasing peptide (GRP) is a developmentally regulated bioactive peptide believed to function as a pulmonary growth factor. It is produced by pulmonary neuroendocrine cells, found within the conducting and respiratory epithelium, as isolated cells and in clusters known as neuroepithelial bodies (NEBs). Deficient GRP expression has been reported in pulmonary hypoplasia (PH) associated with oligohydramnios and diaphragmatic hernia. To assess further the role of GRP in maldeveloped lung we reviewed the postmortem records and histologic lung sections, stained with H&E and anti-GRP antiserum, from 11 infants with anencephaly and 11 age-matched controls. Cells immunoreactive for GRP were quantified (isolated versus NEBs) in airways and airspaces per mm2 for a standard area. PH was present in five anencephalic infants. There was no difference in the total number of GRP-positive cells, number of NEBs, size of NEBs, or number of GRP-positive cells in airways or alveoli in either group regardless of lung development. A greater proportion of the GRP-positive cells was present in the airways in anencephalic infants with PH (58%) compared with anencephalic infants without PH (40%) (P = .018). There were no differences when comparing these groups with control infants and no differences in the density of airways in each of these groups. We conclude that deficient GRP expression is not a feature of lung hypoplasia in anencephalic infants. The altered distribution of GRP-positive cells in anencephalic infants with PH may be a reflection of the structural abnormalities or accompanying altered cellular maturity.

Anencephaly↗
PubMed1995

[Diaphragmatic paralysis and respiratory insufficiency].

BACKGROUND: Phrenic nerve palsy leads to disfunction of the main respiratory muscle. With bilateral palsy dyspnoea in the supine body position will typically occur. With one-sided lesion symptoms will only appear when a second pulmonary disease is present. PATIENTS: We refer of 6 patients with bilateral and 5 with unilateral diaphragmatic paresis. In 3 patients neuralgic shoulder-arm-amyotrophy was diagnosed, in further 4 there was suspicion of it. Amyotrophic lateral sclerosis developed in 2 after 4 respectively 8 months. In 1 case a cervical operation led to palsy, mediastinitis in 1 case. Lung function tests showed a restrictive pattern, especially in bilateral palsy. RESULTS: Vital capacity was reduced by almost 50% respectively 25% in the supine body position. Mouth occlusion pressure reduction was apparent. Near normal to marked hyperkapnia developed in bilateral paresis. In 5 cases non-invasive intermittent ventilation is instituted (2 volume controlled, 3 pressure supported). Two patients died (1 patient with amyotrophic lateral sclerosis after 13 months, 1 with malignant pleurisy after 4 months). Three patients continued non-invasive intermittent ventilation since 14 to 64 months.

Adult↗
PubMed1995

Techniques in the composite reconstruction of extensive thoracoabdominal tumor resections.

BACKGROUND: This report illustrates the unique problems of reconstructing thoracoabdominal wall defects coexisting with diaphragmatic defects. STUDY DESIGN: Two patients with extensive primary chest wall tumors (chondrosarcoma and desmoid tumor) underwent aggressive resection of the hemithorax, hemidiaphragm, and anterior chest wall for cure. The combined chest and abdominal wall defect was greater than 625 cm2 in both cases. RESULTS: Functional restoration of these massive thoracoabdominal defects was accomplished by use of polypropylene-methyl methacrylate prostheses and vascularized tissue coverage. The requirements for rigidity, protection, and esthetic contouring of the chest wall are satisfied by this reconstruction. This technique also offers the flexibility and durability that the abdominal wall requires. Repair of the diaphragm using this technique is secure and simple. CONCLUSIONS: Our report confirms the principle that, with modern thoracic and plastic operative techniques, the extent of tumor resection should not be compromised because of concern over the ability to reconstruct the defect.

Abdominal Neoplasms↗
PubMed1986

In vivo length-force relationship of canine diaphragm.

Diaphragmatic length was measured by sonomicrometry and transdiaphragmatic pressure (Pdi) by conventional latex balloons in eight dogs anesthetized with pentobarbital sodium under passive conditions and during supramaximal phrenic stimulation. The passive length-pressure relationship indicates that the crural part of the diaphragm is more compliant than the costal part. With supramaximal stimulation the costal diaphragm showed a length-pressure relationship similar in shape to in vitro length-tension curves previously described for the canine diaphragm. The crural part has a smaller pressure-length slope than the costal part in the length range from 80% of optimum muscle length (Lo) to Lo. At supine functional residual capacity (FRC) the resting length (LFRC) of the costal and crural diaphragms are not at Lo. The costal part is distended to 105% of Lo, and crural is shortened to 92% of Lo. Tidal shortening will increase the force output of costal while decreasing that of the crural diaphragm. The major forces setting the passive supine LFRC are the abdominal weight (pressure) and the elastic recoil of the lungs. The equilibrium length (resting length of excised diaphragmatic strips) was 79 +/- 3.6% LFRC for the costal diaphragm and 87 +/- 3.9% LFRC for the crural diaphragm. Similar shortening was obtained in the upright position, indicating passive diaphragmatic stretch at supine LFRC.

Animals↗
PubMed1990

Inspiratory and expiratory muscle function during continuous positive airway pressure in dogs.

Continuous positive airway pressure (CPAP) is known to produce activation of the expiratory muscles. Several factors may determine whether this activation can assist inspiration. In this study we asked how and to what extent expiratory muscle contraction can assist inspiration during CPAP. Respiratory muscle response to CPAP was studied in eight supine anesthetized dogs. Lung volume and diaphragmatic initial length were defended by recruitment of the expiratory muscles. At the maximum CPAP of 18 cmH2O, diaphragmatic initial lengths were longer than predicted by the passive relationship by 52 and 46% in the costal and crural diaphragmatic segments, respectively. During tidal breathing after cessation of expiratory muscle activity, a component of passive inspiration occurred before the onset of inspiratory diaphragmatic electromyogram (EMG). At CPAP of 18 cmH2O, passive inspiration represented 24% of the tidal volume (VT) and tidal breathing was within the relaxation characteristic. Diaphragmatic EMG decreased at CPAP of 18 cmH2O; however, VT and tidal shortening were unchanged. We identified passive and active components of inspiration. Passive inspiration was limited by the time between the cessation of expiratory activity and the onset of inspiratory activity. We conclude that increased expiratory activity during CPAP defends diaphragmatic initial length, assists inspiration, and preserves VT. Even though breathing appeared to be an expiratory act, there remained a significant component of active inspiratory diaphragmatic shortening, and the major portion of VT was produced during active inspiration.

Abdominal Muscles↗
PubMed2004

[Neurophysiological investigations of respiratory function].

Neurophysiological assessment of breathing is mandatory for the diagnosis and management of respiratory problems occurring in neuromuscular disorders (neuromuscular complications of critical illness, spinal cord trauma, C4-C5 radiculopathies, phrenic nerve neuropathy, diabetes mellitus, Guillain-Barré syndrome etc...). We review the methods of exploration (principles and normative data) of efferent pathways (phrenic nerve conduction, central motor conduction studies with transcranial magnetic stimulation, diaphragmatic EMG) and afferent pathways (somatosensory evoked potentials of the phrenic nerve, respiratory evoked potentials, sympathetic skin response during sudden occlusion of respiratory pathways during inspiration), as well as their main indications.

Afferent Pathways↗
PubMed1996

"Diverticula" of anterior mitral valve leaflet as a cause of subvalvular aortic stenosis.

A 77-year-old male patient presented with symptoms of shortness of breath, fatigue, chest pain on exertion and dizziness. Transthoracic echocardiography suggested the presence of a diaphragmatic type of obstruction in the subaortic area of the left ventricular outflow tract. The systolic peak gradient at rest was 34 mmHg with a mean of 23 mmHg. Cardiac catheterization demonstrated rounded radiolucencies in the left ventricular outflow tract in the form of two "pouches" that moved back and forth causing subaortic stenosis. There was also a 70% stenosis of the left anterior descending coronary artery. Left ventricular function was normal. At surgery, a transesophageal echocardiogram demonstrated two distinct pouches arising from the anterior leaflet of the mitral valve. The larger of the two originated near the free edge of the leaflet and was attached via a chord to the membranous septum traversing the subaortic area of the left ventricular outflow tract. The patient underwent a left internal mammary to left anterior descending bypass graft, excision of the larger pouch and over-sewing of the smaller pouch. The excision and repair were performed through the aortic root and aortic valve. The patient made an uncomplicated recovery and on follow up his symptoms disappeared. This case shows the excellent results that can be obtained by surgery of diverticula of the mitral valve causing intermittent subaortic stenosis, a rare pathologic entity, morphologically different from the classical diaphragmatic subaortic stenosis.

Aged↗
PubMed2005

The singer's breath: implications for treatment of persons with emphysema.

This study investigated the effects of group singing instruction on the physical health and general wellness of senior citizens with emphysema. Subjects (n = 7) participated in 6 weeks of group vocal instruction, which emphasized breath management techniques. Dependent measures reflected physical health, functional outcomes, and quality of life. No significant differences were found on measures of physical health (FEV1, inspiratory threshold, distance walked, and The DUKE physical health subscale). Measures of functional outcomes each showed a significant change across time. Results of the ANOVAs for breath management (extent of counting) and breath support (intensity of speech) were significant (p < .038 & p < .000 respectively). Descriptive analyses showed a clear and dramatic shift in breathing mode from clavicular to diaphragmatic breathing that was maintained 2 weeks after the treatment period. Quality of life measures (subjective scales and The Duke Health Profile) yielded mixed results. Findings of this study suggest that vocal instruction, inclusive of breathing exercises, may help to improve the quality of life for senior citizens with emphysema. Subjects in this study responded positively to the instruction and further investigation of the treatment method is warranted.

Aged↗
PubMed1998

Hepatic hydrothorax.

Hepatic hydrothorax is the accumulation of ascitic fluid in the pleural space and requires the same treatment as ascites: salt restriction, diuretics, and paracentesis. Refractory hydrothorax appears when there is no response to those measures and its management is not well established. Videothoracoscopy is a promising therapy that permits the detection and closure of diaphragmatic defects, and when used with pleurodesis resulted in long-lasting control of hydrothorax in six of eight patients without appreciable morbidity. The transjugular intrahepatic portosystemic shunt is an effective therapy in more than 75% of refractory hydrothorax cases. Hepatic encephalopathy and worsening of liver function in some patients are the main adverse effects. Spontaneous bacterial empyema, the infection of a hydrothorax, was reported in 13% of 120 cirrhotic patients with hydrothorax. Forty percent of the episodes of spontaneous bacterial empyema were not associated with spontaneous bacterial peritonitis. The sensibility of pleural fluid culture improves inoculating pleural fluid into a blood culture bottle at the bedside. Patients with refractory hydrothorax or those having an episode of spontaneous bacterial empyema should be considered candidates for liver transplantation.

Anti-Bacterial Agents↗