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PubMed1988

[Total and segmental contractile function of the left ventricle in acute myocardial infarction studied by angiography].

An angiographic study of 50 patients with acute myocardial infarction was carried out in order to assess total and segmental left-ventricular contractility. The comparison of left-ventricular activity in patients with transmural vs. nontransmural anterior myocardial infarction demonstrated no differences, related to the type of lesion. The type of affection of the infarction-linked artery largely influences left-ventricular activity. Nontransmural diaphragmatic myocardial infarction was associated with the least left-ventricular dysfunction. Various functional left-ventricular disorders corresponded to definite central hemodynamic patterns, associated with myocardial infarction.

Adult↗
PubMed1990

Pulmonary sequelae in survivors of congenital diaphragmatic hernia.

Nineteen survivors of congenital diaphragmatic hernia repair were compared with age and sex matched control children six to 11 years after repair. All subjects were examined clinically and underwent lung function testing. The patients also had individual lung volumes assessed radiographically and had radionuclide (krypton-81 m, technetium-99 m macroaggregates) ventilation-perfusion (V/Q) lung scans. Four patients had pectus excavatum and two had mild scoliosis. Spirometric measurements were lower in the patients than in the control subjects but only the differences in peak expiratory flow and flow at 50% of expired vital capacity were significant. The radiographic left lung volumes in patients surviving left diaphragmatic repair were larger than expected at 49.3% (SD 2%), suggesting alveolar overdistension. V/Q scans showed a mismatch in the ipsilateral lung, mean Q (40% (7%] being significantly lower than mean V (47% (6%)). In seven patients who had required ventilation for four days or more perfusion to the ipsilateral lung was significantly lower (34% (6%)) than values for the 12 patients ventilated for less than four days (43% (6%)). Survivors of right diaphragmatic repair had a better outcome in terms of relative radiographic lung volumes and V/Q distribution. More severely affected children are now surviving repair of congenital diaphragmatic herniation, with residual pulmonary abnormalities that could produce functional impairment in adult life.

Child↗
PubMed1991

Effect of preoperative stabilization on respiratory system compliance and outcome in newborn infants with congenital diaphragmatic hernia.

To determine whether preoperative stabilization and delay of operative repair of congenital diaphragmatic hernia (CDH) may decrease operative risk, we performed serial pulmonary function tests on 22 newborn infants with CDH and on four infants without pulmonary hypoplasia (two with ileal atresia and two with tracheoesophageal anomalies) who served as control subjects. We used 2 passive respiratory mechanics technique to measure respiratory system compliance. All patients with CDH had respiratory distress immediately after birth, and required mechanical ventilation. Thirteen babies underwent emergency repair (six survived, seven died); nine of them received extracorporeal membrane oxygenation (ECMO) after the operation (two survived, seven died). Operative repair was delayed deliberately for 2 to 11 days in nine infants with severe hypoxemia. Six immediately received ECMO for 4 to 10 days; one died of intraventricular hemorrhage, and five survived and later underwent surgical repair. The seventh patient did not receive ECMO but appeared to have respiratory distress syndrome of infancy and improved after administration of synthetic surfactant. Improvement was seen in two additional infants who received conventional assisted ventilation during a 48-hour delay before surgery, and survived. In all, eight of nine infants who underwent preoperative stabilization survived (p less than 0.05 compared with survival after emergency surgery). Following surgical repair immediately after birth, respiratory system compliance improved only slightly during the first week of life, a time when control infants had a rapid increase in respiratory system compliance (p less than 0.001). In contrast, respiratory system compliance increased nearly twofold in the nine patients undergoing preoperative stabilization (p less than 0.02). Preoperative ECMO was associated with an increase in respiratory system compliance of more than 60% for 1 week, a significant difference from respiratory system compliance among patients undergoing emergency CDH repair (p less than 0.05). These observations provide physiologic evidence of possible benefits of preoperative stabilization before repair of CDH.

Extracorporeal Membrane Oxygenation↗
PubMed1981

The use of preserved human dura for closure of abdominal wall and diaphragmatic defects.

The surgical management of large body wall defects presents special challenges. The prosthetic materials employed for these defects, although readily available, have the disadvantage of susceptibility to infection. Autologous tissue is frequently not available in sufficient quantity. The long-term functional and histologic results of the use of preserved human dura for closure of abdominal wall and diaphragmatic defects have been evaluated. Dural patches were sutured into abdominal wall and diaphragmatic defects of six dogs, using interrupted sutures of Dexon and Prolene. The animals were killed eight, 16 and 24 weeks after patch placement. The strength of the material was tested with a pneumoperitoneum prior to death and in all animals it appeared firmly incorporated into the host tissue. Histologically there was a mononuclear inflammatory response seen at eight weeks, with resolution by 24 weeks. Ingrowth of surrounding collagen and muscular tissue produced a firm union between the homologous material and the host tissue. The results of this study indicate that preserved human dura is an excellent material for closure of body wall defects. It appears to be well tolerated by host tissue and maintains its strength over prolonged periods of time.

Abdominal Muscles↗
PubMed1983

Persistent fetal circulation in neonates postoperatively: the value of manual ventilation.

Three critically ill infants who had persistent fetal circulation postoperatively, refractile to tolazoline and 100% oxygen with mechanical ventilation including continuous positive airway pressure, responded favourably to prolonged manual hyperventilation. Two infants had undergone repair of a diaphragmatic hernia and the third had correction of a tracheoesophageal fistula. Normal respiratory function was documented in two survivors. The third died 14 days postoperatively. The use of this simple technique indicated that perseverance can be rewarded in the treatment of persistent fetal circulation unresponsive to the usual medical management.

Carbon Dioxide↗
PubMed1998

Lung-volume reduction surgery for diffuse emphysema: radiologic assessment of changes in thoracic dimensions.

Patients with severe, diffuse emphysema may be candidates for pneumectomy (lung-volume reduction surgery, LVRS) to improve lung and respiratory muscle function. To identify candidates who might benefit from this surgery, it is necessary to understand how lung volumes and respiratory function are effected. In this article, the authors demonstrate a significant difference in lung size on chest radiographs obtained before and after surgery. Thirty-five of 71 consecutive patients undergoing LVRS had both preoperative and postoperative chest radiographs and pulmonary function tests available for retrospective review. Preoperative and postoperative measurements of lung height, transthoracic diameters, mediastinal width, heart size, diaphragmatic arc, and intercostal spaces were compared using paired t-tests. Radiographic measurements where also correlated with changes in lung volumes as measured by pulmonary function tests. Lung heights (right, left, mean lateral) and coronal diameter at the aortic arch were reduced after surgery (all p < 0.05). Forced vital capacity, forced expiratory volume in 1 second (FEV1), and vital capacity increased, and total lung capacity and residual volume decreased after surgery (all p < 0.05). Left lung height showed a significant correlation (p = 0.025) with FEV1; all other correlations between radiographic changes and pulmonary function test changes were not significant. The explanation for improved lung function in patients after LVRS is not completely clear and is probably multifactorial. Radiologic alterations reflect anatomic changes caused by surgery and support the theory that modifications of chest wall configuration occur and are likely responsible, in part, for improved symptomatology and respiratory function.

Adult↗
PubMed1996

Respiratory dysfunction related to diaphragmatic shoulder pain after abdominal and pelvic laparoscopy.

Many recent studies registered respiratory dysfunction after laparoscopic surgery; it is well known that the stimulation of the diaphragmatic tendon centre produces a typical shoulder pain. We hypothesize that diaphragmatic tendon centre stress causes postlaparoscopic ventilatory alterations; the aim of this study was to verify whether clinically respiratory dysfunction and shoulder pain relationship exists, after laparascopy with or without contemporaneous stimulation of gallbladder area. So we evaluated, preoperatively and 24 hours after the operation, 20 patients undergoing laparoscopic cholecystectomy (CP), 20 gynaecological patients undergoing laparoscopic ovarian surgery (GP) and 20 control patients undergoing orthopaedic limbs operations (OP) by pulmonary function tests, using computerized spirometry. Diaphragm referred pain was assessed for location and intensity. No orthopaedic patient showed postoperatively pain or pulmonary dysfunction demonstrating that the typical postlaparoscopic restrictive pattern is independent of general anaesthesia. In the CP and GP groups postoperative pulmonary functions were significantly reduced if compared with the orthopaedic control group but not significantly different between them. Moreover, 8 patients from the CP group and 13 from the GP group referred diaphragmatic pain: they showed significantly greater reduction of pulmonary function in comparison with the patients without pain in the respective groups. We conclude that diaphragmatic dysfunction after pneumoperitoneum, and not gallbladder area stimulation, seems to play the most important role in the pathogenesis of both shoulder pain and respiratory restrictive abnormalities after laparoscopy.

Abdomen↗
PubMed2006

Obstetric MRI.

Ultrasound is the imaging modality of choice for pregnant patients. However, MRI is increasingly utilized in patients in whom the sonographic diagnosis is unclear. These include maternal conditions unique to pregnancy such as ectopic pregnancy, placenta accreta, and uterine dehiscence. MRI is also being increasingly utilized in the assessment of abdominopelvic pain in pregnancy, in particular in assessment for appendicitis. Fetal MRI is performed to assess central nervous system (CNS) abnormalities and patients who are considering fetal surgery for conditions such as neural tube defects, congenital diaphragmatic hernia, and masses that obstruct the airway. In the future, functional MRI and fetal volumetry may provide additional information that can aid in our care of complicated pregnancies.

Central Nervous System↗
PubMed1996

Transdiaphragmatic pressure gradients and the lower esophageal sphincter after tight abdominal wall plication in the rat.

BACKGROUND: Gastroesophageal reflux (GER) is increasingly recognized as a complication of surgical closure of gastroschisis and omphalocele. AIM: This study tests the hypothesis that forceful abdominal wall closure reinforces the transdiaphragmatic pressure gradients that constitute the main GER-driving force and challenges the antireflux barrier. MATERIALS AND METHODS: Abdominal and esophageal pressures as well as lower esophageal sphincter pressures (LESP) and length (LESL) were measured in 17 adult rats before tight abdominal wall plication, after it, and 1 week later. RESULTS: This maneuver increased the transdiaphragmatic expiratory gradient from 0.67 +/- 1.31 to 6.97 +/- 2.68 mm Hg (P < .01) and the inspiratory gradient from 4.36 +/- 1.13 to 10.79 +/- 2.31 mm Hg (P < .01) by markedly increasing both the expiratory (from 1.47 +/- 0.74 to 9.44 +/- 1.85 mm Hg; P < .01) and inspiratory (from 0.98 +/- 0.69 to 6.83 +/- 1.55 mm Hg; P < .01) intraabdominal pressures. These changes were transient, and all pressures became normal after 1 week. The antireflux barrier functioned properly under these new conditions because both LESP and the diaphragmatic pinch-cock pressure (DPP) increased, from 20.3 +/- 3.63 to 26.5 +/- 4.31 mm Hg (P < .01) and from 16.4 +/- 7.25 to 22.5 +/- 4.36 mm Hg (P < .01), respectively, while LESL remained unchanged. CONCLUSION: Tight abdominal wall plication in the rat generates high intraabdominal pressures and thus reinforces the transdiaphragmatic pressure gradients, but these conditions elicit a healthy barrier response with sphincteric reinforcement. In addition, these changes are transient and fade out some time after operation. These facts should be taken into account for understanding the pathogenesis of GER after repair of abdominal wall defects in human babies.

Abdominal Muscles↗
PubMed1988

Arnold-Chiari malformation and paralysis of the diaphragm.

A woman aged 17 years presented with symptoms of somnolence. A bilateral diaphragmatic paralysis and an Arnold-Chiari malformation were diagnosed. Lung function tests revealed a marked restrictive defect and a blunted ventilatory response to hypercapnia and hypoxia. A sleep study also showed central apneas, an irregular pattern of breathing and marked hypoventilation.

Adolescent↗
PubMed1999

[Motor neuron disease with respiratory insufficiency as primary manifestation].

A 66-year-old man with dyspnea on exertion suffered a cardiac arrest and was referred to our hospital after emergency room intubation. Chest X-ray films detected no abnormalities. Blood gas analysis showed hypoxemia with normal A-aDO 2, and pulmonary function tests revealed combined ventilatory impairment. Chest fluoroscopy revealed weakness of diaphragmatic motion. No other abnormalities were found on initial examination. It was difficult to wean the patient off mechanical ventilation and identify the cause of alveolar hypoventilation. On the 60th hospital day, a neurological examination and electromyography disclosed fasciculation and denervation of the left biceps and pectoralis major muscle. These findings supported the diagnosis of motor neuron disease (MND). Although respiratory insufficiency as an initial symptom of MND is unusual, physicians should be aware of the possibility of MND in cases of alveolar hypoventilation of unknown etiology.

Aged↗
PubMed2001

Anatomic landmarks to estimate the length of the diaphragm from chest radiographs: effects of emphysema and lung volume reduction surgery.

STUDY OBJECTIVES: To define anatomic landmarks that can be used to predict insertions of the diaphragm on chest radiographs and to estimate diaphragm length. DESIGN: Prospective clinical trial with a parallel group design. SETTING: Laboratory investigations in normal volunteers recruited by advertisement and in emphysema outpatients being evaluated for elective bilateral lung volume reduction surgery (LVRS). PATIENTS: Twenty-six normal subjects classified into young and older age groups, with a third group of 13 emphysema patients matched for age and sex with the older group. MEASUREMENTS: Identification and between-group comparisons were made of anatomic landmarks on anteroposterior and lateral chest radiographs obtained at total lung capacity. Predicted landmarks were generated from normal subjects. Within-subject and between-group comparisons were made of diaphragm length index (DLI) based on observed anatomic landmarks (DLIobs) and diaphragm length index based on predicted anatomic landmarks (DLIpred) at functional residual capacity. RESULTS: Anatomic landmarks were not different between the three groups or between male and female subjects, and were not different before and after LVRS in emphysema patients. No difference was found between DLIobs and DLIpred in normal subjects and emphysema patients, but both were smaller in emphysema patients than in normal subjects and increased after LVRS in emphysema patients. CONCLUSION: This study validates the use of anatomic landmarks to estimate DLI. Using these landmarks simplifies the determination of diaphragmatic lengths and could be a useful tool for the evaluation of the functional capacity of the diaphragm, and possibly as a prognostic indicator of patients who are candidates for LVRS.

Adult↗
PubMed2002

Effects of halothane and isoflurane on the contraction, relaxation and energetics of rat diaphragmatic muscle.

BACKGROUND: The inotropic effects of halogenated anaesthetics on diaphragmatic muscle remain a matter of debate. Their effects on its relaxation are poorly understood, although diaphragmatic relaxation is recognized as an important physiological process that may interfere with diaphragmatic performance, fatigue and arterial blood flow. METHODS: The effects of halothane and isoflurane (1 or 2 x minimum alveolar concentration [1 or 2 MAC]) on contraction and relaxation of rat diaphragm muscle strips (n = 40) were studied in vitro from force-velocity curves obtained at various loads from isotonic to isometric conditions. From these curves we determined the peak power output and the curvature. Data are mean (SD) percentage of baseline values. RESULTS: At I MAC, isoflurane and halothane induced no significant inotropic and lusitropic effects. At 2 MAC, isoflurane induced a negative inotropic effect (active force, 93(5)% of baseline). Halothane and isoflurane induced a significant decrease in the peak power output at 2 MAC (88(8) and 86(9)% of baseline; P < 0.05), without significant changes in the curvature of the force-velocity curve. At 2 MAC isoflurane under high loads and halothane under low loads induced moderate negative lusitropic effects. CONCLUSION: Halothane and isoflurane induced very moderate inotropic and lusitropic effects, suggesting that the decrease in diaphragm function observed in vivo is not related to a direct effect on diaphragmatic contractility.

Anesthetics, Inhalation↗
PubMed2002

Lumbar stiffness but not thoracic radiographic changes relate to alteration of lung function tests in ankylosing spondylitis.

Involvement of the costovertebral (CV) and costotransverse (CT) as well as the sacroiliac (SI) joints is known to occur in patients with ankylosing spondylitis (AS). The functional significance of these changes is not clear. We have performed clinical and radiological evaluations and assessed the effect of joint involvement on pulmonary function. We detected radiologic evidence of involvement of the CV joint in 80% of patients and of the CT joint in 60 %. We found a direct relation between the severity of CV, CT and SI joint affliction, and the severity of CV and SI joints were related to time of evolution of the disease. Pulmonary function tests revealed neither restrictive nor obstructive defects. No relation was found between pulmonary function and CV and CT joint affliction. Patients with stiffer spines had a tendency to have pulmonary function tests within the lower limit of the normal range. In patients with AS diaphragmatic breathing might compensate the chest respiration to some extent.

Adult↗
PubMed2003

The adrenal cortex in experimental congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: Adrenal cortical malfunction was found recently in patients with severe congenital diaphragmatic hernia (CDH). The current study tests the hypothesis that the development and function of the adrenal cortex could be abnormal in an experimental model of CDH. METHODS: Pregnant rats were exposed on day 9.5 of gestation to 100 mg of 2-4-dichlorophenyl-p-nitrophenyl ether (nitrofen) diluted in olive oil. The sham group was treated only with oil. Fetuses were recovered on the 21st day, bled, and examined for the presence or absence of CDH. Adrenal glands from sham and CDH animals were dissected, weighed, and prepared for histologic, biochemical, and immunohistochemical studies (ki-67) aimed at measuring total DNA, total protein, and the proportion of proliferating cells. Serum corticosterone levels were assayed. The results in both groups were compared with parametric tests with a significance level of P <.05. RESULTS: The adrenal weight was not different in CDH animals versus controls (0.049 +/- 0.014 v 0.052 +/- 0.012% of body weight; not significant). Total DNA was reduced significantly (1.180 +/- 0.481 v 1.909 +/- 0.893 microgram P <.05) with unchanged DNA to protein ratio. Proliferation index in both groups was 20.1 +/- 3.1% and 26.5 +/- 7.5%, respectively (not significant), and the proliferating cells were mainly located in the glomerular areas of the glands. Corticosterone levels were similar in both groups. CONCLUSIONS: Nitrofen induces very slight changes in the development of adrenal glands of fetal rats, expressed by reduced cell proliferation especially in glomerular areas, reduced total DNA with preservation of cell sizes (constant DNA to protein ratio), with no change in function because corticosterone levels remained unchanged. It is doubtful that primary adrenal malformation/malfunction contributes to the severity of CDH in this model.

Adrenal Cortex↗
PubMedDate not supplied

Restrictive lung disease due to diaphragmatic dysfunction in systemic lupus erythematosus. Two case reports.

Two patients with systemic lupus erythematosus and unexplained dyspnea are described. Both had severe dyspnea and a restrictive lung function pattern without any apparent specific pathology. Both patients initially responded to corticosteroids and/or immunosuppression; one patient, however, relapsed and eventually died. Many factors may contribute to this syndrome, including diaphragmatic dysfunction, splinting of the diaphragm, pleuritis, atelectasis and respiratory muscle dysfunction. This syndrome, which may respond to steroids or immunosuppressive treatment, must be considered in SLE patients with dyspnea lacking a concrete underlying cause.

Adult↗