PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Diaphragmatic function”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 505 records · Page 28Linked to original sources
PubMed1989

[Initial measures in newborn infants with surgically correctable abnormalities].

In newborns with surgically correctable malformations the quality of primary care has considerable influence on the results of the eventual surgical repair. This is particularly true for extensive diaphragmatic and abdominal wall defects as well as for esophageal and intestinal atresia, exstrophy of the bladder and urogenital malformations. The neonatal management comprises measures generally valid for all diseased newborns and measures specific for the particular malformation. The general care concerns heat regulation, fluid balance and other vital functions. Specific regimens are necessary as primary care for diaphragmatic hernia, esophageal atresia, abdominal wall defects and neonatal bowel obstruction. Furthermore this primary management must be extended to include the care of the pregnant mother. Already in utero infants with diaphragmatic and esophageal malformations should be referred to the gynecological-neonatal center.

Abnormalities, Multiple↗
PubMed1996

Comparison of early functional results after volume reduction or lung transplantation for chronic obstructive pulmonary disease.

BACKGROUND: Bilateral lung volume reduction is designed to improve pulmonary function in selected patients with severe emphysema by improving diaphragmatic and chest wall mechanics. Early results of lung volume reduction suggest significant improvement to selected patients with chronic obstructive pulmonary disease, some of whom might otherwise be considered for lung transplantation. The purpose of this review was to compare intermediate results of volume reduction with single and bilateral lung transplantation. METHODS: Functional performance and survival after volume reduction were compared with single and bilateral sequential lung transplantation. After evaluation, patients were enrolled in a supervised intensive preoperative and postoperative program of pulmonary rehabilitation. Functional assessment, including pulmonary function tests, room air arterial blood gas analysis, and 6-minute walk distance, was obtained before the operation and 3, 6, and 12 months after the operation. RESULTS: Thirty-three patients underwent volume reduction (mean age 57 years), 39 patients single lung transplantation (55 years), and 27 patients bilateral lung transplantation (49 years). Early mortality was 0, 1 of 39, and 2 of 25 and mortality at 12 months was 1 of 33, 4 of 39, and 4 of 25 in the volume reduction, single, and bilateral lung transplantation groups, respectively. At 6 months, mean forced expiratory volume in 1 second was improved by 79% (volume reduction), by 231% (single lung transplantation), and by 498% (bilateral lung transplantation) over preoperative values. Exercise endurance as measured by 6-minute walk distance increased by 28% (volume reduction), by 47% (single lung transplantation), and by 79% (bilateral lung transplantation) from baseline. At 6 months, all patients having single or bilateral lung transplantation and 26 of 33 patients having volume replacement were free of supplemental oxygen. CONCLUSIONS: Although single and bilateral lung transplantation result in superior lung function, volume reduction achieves satisfactory improvement of disabling symptoms early after operation while avoiding immunosuppression and transplant-specific complications. Our experience suggests that (1) volume reduction is a suitable alternative in selected patients eligible for transplantation; (2) volume reduction provides an earlier option for treatment in patients who may require transplantation at some future date; (3) volume reduction is the only surgical treatment available to the many patients who are not current or future transplant candidates. Conversely, in patients not suitable for volume reduction, transplantation remains the only choice for surgical therapy.

Female↗
PubMed2001

Fetal lung volume measurement by magnetic resonance imaging in congenital diaphragmatic hernia.

OBJECTIVE: To study the potential for prenatal magnetic resonance imaging to predict pulmonary hypoplasia in congenital diaphragmatic hernia. DESIGN: Prospective observational study. SETTING: Tertiary care centre. PARTICIPANTS: Thirteen cases of congenital diaphragmatic hernia (11 left, 2 right) without associated anomalies and 74 controls. METHODS: Measurements by magnetic resonance imaging of fetal lung volume were achieved. In the control fetuses, a regression analysis was performed to associate fetal lung volume with gestational age. This yielded a formula allowing calculation of the expected fetal lung volume as a function of gestational age. In the cases with congenital diaphragmatic hernia, the observed/expected fetal lung volume ratio was compared with perinatal outcome. MAIN OUTCOME MEASURES: Neonatal mortality and pulmonary hypoplasia, which was defined as lung/body weight ratios less than 0.012. RESULTS: The expected fetal lung volume was derived from the following formula: Fetal lung volume (mL) = exp (1.24722 + 0.08939 x gestational age in weeks). The observed/expected fetal lung volume ratio was significantly lower in congenital diaphragmatic hernia (median: 0.31, range: 0.06-0.63), than in controls (median: 0.99, range: 0.42-1.94). This ratio was significantly less in the infants with congenital diaphragmatic hernia who died (median: 0.26, range: 0.06-0.63) compared with those who survived (median: 0.46, range: 0.35-0.56). The observed: expected fetal lung volume ratio was significantly correlated with the post mortem lung: body weight ratio. CONCLUSION: In isolated congenital diaphragmatic hernia, fetal lung volume measurement by magnetic resonance imaging is a potential predictor of pulmonary hypoplasia and postnatal outcome. Further studies are required to establish the clinical value of magnetic resonance imaging for the prenatal assessment of fetal lungs.

Case-Control Studies↗
PubMed1986

Functional adaptation of diaphragm to chronic hyperinflation in emphysematous hamsters.

Costal strips of diaphragmatic muscle obtained from animals with elastase-induced emphysema generate maximum tension at significantly shorter muscle fiber lengths than muscle strips from control animals. The present study examined the consequences of alterations in the length-tension relationship assessed in vitro on the pressure generated by the diaphragm in vivo. Transdiaphragmatic pressure (Pdi) and functional residual capacity (FRC) were measured in 22 emphysematous and 22 control hamsters 4-5 mo after intratracheal injection of pancreatic elastase or saline, respectively. In 12 emphysematous and 12 control hamsters Pdi was also measured during spontaneous contractions against an occluded airway. To allow greater control over muscle excitation, Pdi was measured during bilateral tetanic (50 Hz) electrical stimulation of the phrenic nerves in 10 emphysematous and 10 control hamsters. Mean FRC in the emphysematous hamsters was 183% of the value in control hamsters (P less than 0.01). During spontaneous inspiratory efforts against a closed airway the highest Pdi generated at FRC tended to be greater in control than emphysematous hamsters. When control hamsters were inflated to a lung volume approximating the FRC of emphysematous animals, however, peak Pdi was significantly greater in emphysematous animals (70 +/- 6 and 41 +/- 8 cmH2O; P less than 0.05). With electrophrenic stimulation, the Pdi-lung volume curve was shifted toward higher lung volumes in emphysematous hamsters. Pdi at all absolute lung volumes at and above the FRC of emphysematous hamsters was significantly greater in emphysematous compared with control animals. Moreover, Pdi continued to be generated by emphysematous hamsters at levels of lung volume where Pdi of control subjects was zero.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗
PubMed1993

Radiographic evidence of bronchopulmonary dysplasia in high-risk congenital diaphragmatic hernia survivors.

Congenital diaphragmatic hernia is a congenital malformation associated with pulmonary hypoplasia. It often leads to respiratory failure, requiring artificial ventilation with high inflation pressures and high percentages of oxygen. We evaluated radiographic evidence of bronchopulmonary dysplasia (BPD) in survivors, who presented with respiratory distress within 6 hours after birth, by a radiographic scoring system measuring the severity of BPD by the Toce score and the degree of pulmonary hypoplasia by the Touloukian score. Fifteen of 45 survivors (33 percent) had clinical and radiological lung disease resembling BPD. As a group they had significantly higher Touloukian and Toce scores than survivors without BPD. Morbidity expressed as the duration of artificial ventilation, supplemental oxygen, and hospital stay was much higher in the BPD group. The hypoplastic lung in infants with congenital diaphragmatic hernia appears to be as susceptible to barotrauma and pulmonary oxygen toxicity as the lungs of prematurely born infants. To what extent BPD occurring in congenital diaphragmatic hernia survivors might influence the future development of lung function is not yet known.

Bronchopulmonary Dysplasia↗
PubMed2003

Left diaphragmatic eventration diagnosed as congenital diaphragmatic hernia by prenatal sonography.

Congenital diaphragmatic eventration is an abnormal elevation of the diaphragm resulting from failure of muscle fibers to develop during gestation. A mediastinal shift to the contralateral side may cause significant compression of the affected chest contents, resulting in compromised pulmonary function, especially when both sides are involved. Differentiating between congenital diaphragmatic eventration and congenital diaphragmatic hernia is very difficult but important because eventration has a better perinatal outcome than diaphragmatic hernia has. This report discusses a case of congenital diaphragmatic eventration that was initially diagnosed by prenatal sonography as a diaphragmatic hernia on the left side. In this case, the correct diagnosis was made at the time of surgery shortly after the infant's birth. The defect was repaired by plication, and the infant's outcome was favorable. Although the initial diagnosis was incorrect in this case, the use of sonography can aid in the prenatal detection and diagnosis of congenital diaphragmatic anomalies.

Adult↗
PubMed2004

Symptomatic diaphragmatic endometriosis ten years after total abdominal hysterectomy.

BACKGROUND: Endometriosis is a disease that affects women, mostly in the age range of 25-35 years, and in most cases pelvic organs are involved. Involvement of the diaphragm after hysterectomy is extremely uncommon. CASE: A 50-year-old woman presented to our department with right upper-quadrant abdominal pain. Ten years before her admission, she underwent total hysterectomy and right salpingo-oophorectomy for a large leiomyomatous uterus. On evaluation, a right diaphragmatic lesion was identified by computed tomography. An explorative laparotomy was then performed, which revealed a 4-cm diaphragmatic cyst compressing the liver surface and containing thick chocolate-colored material. The lesion was totally excised. Pathological examination confirmed the diagnosis of endometriotic cyst. CONCLUSION: The diagnosis of endometriosis involving the diaphragm with no evidence of disease in the pelvis 10 years after hysterectomy, although a rare situation, should be considered in the differential diagnosis of a symptomatic diaphragmatic lesion in a woman with a single functioning ovary.

Abdominal Pain↗
PubMed1987

Effects of continuous positive airway pressure on upper airway and respiratory muscle activity.

To study the effects of continuous positive airway pressure (CPAP) on lung volume, and upper airway and respiratory muscle activity, we quantitated the CPAP-induced changes in diaphragmatic and genioglossal electromyograms, esophageal and transdiaphragmatic pressures (Pes and Pdi), and functional residual capacity (FRC) in six normal awake subjects in the supine position. CPAP resulted in increased FRC, increased peak and rate of rise of diaphragmatic activity (EMGdi and EMGdi/TI), decreased peak genioglossal activity (EMGge), decreased inspiratory time and inspiratory duty cycle (P less than 0.001 for all comparisons). Inspiratory changes in Pes and Pdi, as well as Pes/EMGdi and Pdi/EMGdi also decreased (P less than 0.001 for all comparisons), but mean inspiratory airflow for a given Pes increased (P less than 0.001) on CPAP. The increase in mean inspiratory airflow for a given Pes despite the decrease in upper airway muscle activity suggests that CPAP mechanically splints the upper airway. The changes in EMGge and EMGdi after CPAP application most likely reflect the effects of CPAP and the associated changes in respiratory system mechanics on the afferent input from receptors distributed throughout the intact respiratory system.

Adult↗
PubMed1987

Maturation of spontaneous fetal diaphragmatic activity and fetal response to hypercapnia and hypoxemia.

The electromyogram (EMG) of the diaphragm, lateral rectus, and nuchal and hindlimb muscles were studied during spontaneous activity and during hypercapnia or hypoxemia in eight fetal sheep from 0.5 to 0.8 gestation (73-128 days). At the earliest gestational age, diaphragmatic EMG activity was mainly tonic and associated with tonic activity of somatic muscles. The stimulus for the diaphragmatic activity originated centrally. Brief periods of a rapid-eye-movement (REM) state characterized by phasic lateral rectus and diaphragmatic activity and absence of nuchal activity were recognized. Furthermore, from 0.5 to 0.7 gestation onward, activity of all muscles increased. Thereafter increased specificity of activity in relation to the apparent REM and non-rapid-eye-movement (NREM) state occurred. With maturation, phasic diaphragmatic activity increased at the expense of tonic activity. The most striking effect of maturation on apnea was a greater proportion of apnea lasting greater than 1 min, but the total duration of apnea as a percent of a total recording remained unchanged. The quantitative response to hypercapnia during maturation was independent of the pattern of spontaneous diaphragmatic activity. Hypercapnia at 0.5 gestation changed the pattern of diaphragmatic EMG activity from mainly tonic to phasic. Thus the central chemoreceptors and appropriate neuronal pathways are present and functional as early as 0.5 gestation. Hypercapnia at 0.5 gestation caused a shift in diaphragmatic EMG power to lower frequencies similar to that found during control conditions in the older fetus. This might suggest that during maturation there is increased recruitment of phrenic motoneurons. Hypoxemia abolished tonic somatic activity at 0.5 gestation and decreased phasic diaphragmatic activity at more advanced gestational ages. Therefore the central inhibitory mechanisms of hypoxemia are developed by 0.5 gestation.

Animals↗
PubMed1986

Hepatic coma resulting from diaphragmatic rupture and hepatic herniation.

We treated a unique case of blunt rupture of the right hemidiaphragm that produced acute hepatic failure with jaundice and coma. Laparotomy showed total eventration of the liver into the chest. The hepatic failure was caused by strangulation of the extrahepatic biliary and venous structures. Surgical repair was followed by recovery and normalization of hepatic function. This case stresses the need to diagnose and treat diaphragmatic ruptures promptly to prevent such threatening complications. The diagnosis of right diaphragmatic rupture must be suspected in instances of blunt injury, with an awareness of misleading presentations.

Diaphragm↗
PubMed2000

[The characteristics of the mechanical activity of the respiratory muscles during the diaphragmatic respiration technic].

UNLABELLED: Noteworthy among breathing training techniques is so-called diaphragmatic breathing. In spite of the technique's name, however, little is known of the functional characteristics of this ventilatory method. OBJECTIVE: To asses the mechanics of respiratory muscles, particularly diaphragm muscles, during diaphragmatic breathing in patients with severe chronic obstructive pulmonary disease (COPD). METHODS: Ventilatory pattern and respiratory pressures (abdominal [Pga], intrathoracic [Pes] and transdiaphragmatic [Pdi]) were studied in 10 patients with severe COPD in stable phase (age 69 +/- 6 years, FEV1 33 +/- 12% ref) at baseline and during deep breathing with spontaneous muscle recruitment (SMR) and during breathing training. Measurements were taken with the patient seated and in supine decubitus position. RESULTS: In seated position ventilatory pattern was similar with SMR and during breathing training. Mean Pdi during airflow, however, was greater during breathing training than with SMR (34.8 +/- 8.0 and 29.3 +/- 9.3 cmH2O, respectively, p < 0.05) for similar levels of Pes. Mechanical effectiveness of the diaphragm expressed as Vt/Pdi) was less during breathing training, however (36.1 +/- 10.4 and 49.5 +/- 15.8 cc/cmH2O, p < 0.05), with no changes in overall efficacy of respiratory muscles (Vt/Pes). In supine decubitus position, ventilatory patterns of SMR and breathing training were similar, although Vt and T1 were slightly higher in the latter (1,065 +/- 305 vs. 1,211 +/- 314 cc, p < 0.01; and 2.76 +/- 1.32 vs. 3.07 +/- 1.23 sec, p < 0.05). Pdi was also higher during breathing training (29.7 +/- 10.2 and 38.0 +/- 10.5 cmH2O, p < 0.05), although accompanied in this case by a higher Pes (21.2 +/- 7.5 to 26.4 +/- 8.4 cmH2O, p < 0.005). In supine decubitus position, the effectiveness of both diaphragm muscles and respiratory muscles overall was similar for both ventilatory modes. CONCLUSIONS: Breathing training truly involves greater use of the diaphragm, both in seated and supine decubitus positions. Breathing training does not provide greater ventilatory efficacy than SMR, however, in COPD patients.

Aged↗
PubMed1987

Effect of digitalis on the diaphragm in anesthetized dogs.

We examined the effect of digitalis on diaphragmatic contractility and fatigability in 19 anesthetized mechanically ventilated dogs. The diaphragmatic force was assessed from transdiaphragmatic pressure (Pdi) developed at functional residual capacity against an occluded airway during cervical phrenic nerve stimulation. In a first group of five dogs, Pdi-stimulus frequency relationships were compared before and after administration of ouabain in doses of 0.01, 0.02, and 0.04 mg/kg. In a second group, diaphragmatic fatigue was produced by bilateral phrenic nerve stimulation at 30 Hz. Ten seconds of stimulation and 15 s of mechanical ventilation were repeated for 30 min. The rates of decrease in Pdi were compared between two groups, one of 0.05 mg/kg deslanoside-treated dogs (n = 7) and one of nontreated dogs (n = 7). After ouabain administration Pdi was significantly greater at each frequency in a dose-dependent manner. On the other hand, the rate of decrease in Pdi in the deslanoside group was significantly smaller than that in the nontreated group, whereas deslanoside did not greatly change the Pdi-frequency curves in fresh diaphragm. We conclude that ouabain improves contractility of the fresh diaphragm and that deslanoside has a protective effect against fatigability.

Animals↗
PubMed1985

Peritonitis, dialysate infusion and lung function in continuous ambulatory peritoneal dialysis (CAPD).

Pulmonary function tests were done in seven CAPD patients with acute peritonitis on the day of admission to the hospital and after recovery. Subsequently, the effect of dialysate infusion alone on lung function was studied in 19 patients initiated on CAPD and nine of these patients were restudied 7.6 +/- 4.1 months later. Peritonitis was associated with a 30% reduction in vital capacity and a significant fall in arterial oxygen tension (7 to 11 mmHg) (p less than 0.01). Dialysate infusion alone decreased functional residual capacity (FRC) and produced small changes in PaO2 which were more pronounced in the supine position. The decrease in PaO2 observed in changing from sitting prior to dialysate infusion, to supine after dialysate infusion was due to the development of airways closure at resting lung volumes. Follow-up studies in nine patients demonstrated a continued and significant fall in FRC with dialysate infusion, without however, any changes in PaO2. We conclude that peritonitis in CAPD patients is accompanied by significant changes in lung function which are probably due to a decrease in diaphragmatic mobility resulting in atelectasis and underventilation of dependent lung zones. In CAPD patients without peritonitis, dialysate infusion in the supine position produces significant changes in PaO2, but with time, compensatory mechanisms develop to abolish the changes in PaO2.

Adult↗
PubMed1998

Quantitative analysis of respiratory, motor, and sensory function after supraclavicular block.

UNLABELLED: The incidence and clinical significance of hemidiaphragmatic paresis after supraclavicular block of the brachial plexus is unknown. Eight healthy volunteers received a supraclavicular block with a standard technique using 30 mL of 1.5% lidocaine. Respiratory function was assessed with ultrasound of the diaphragm, respiratory inductive plethysmography (RIP), and pulmonary function tests (PFT) every 20 min. Sensory block was assessed with pinprick and motor block with isometric force dynamometry every 20 min. Four of eight subjects demonstrated hemidiaphragmatic paresis on both ultrasound and RIP. No subject experienced changes in PFT values or subjective symptoms of respiratory difficulty. Motor and sensory blockade outlasted hemidiaphragmatic paresis. These results are contrasted to the often symptomatic, 100% incidence of hemidiaphragmatic paresis seen after interscalene block. In this study of healthy volunteers, supraclavicular block was associated with a 50% incidence (95% confidence interval 14-86) of hemidiaphragmatic paresis that was not accompanied by clinical evidence of respiratory compromise. IMPLICATIONS: Interscalene block is always associated with diaphragmatic paralysis and respiratory compromise. The significance of these side effects after supraclavicular block is unknown. Using sensitive measures of respiratory function, we determined that diaphragmatic paralysis occurs less often with the supraclavicular approach and is not associated with respiratory difficulties in healthy subjects.

Adult↗
PubMed2005

Pulmonary function after complete unilateral phrenic nerve transection.

OBJECT: The status of pulmonary function following phrenic nerve transfer surgery is still largely unknown because of the high degree of variability in the accessory phrenic nerve that may be involved. In the present study, pulmonary functions were assessed in patients before and after full-length phrenic nerve transfer surgery, in whom the phrenic nerve was severed at a location just before its entry into the diaphragm. METHODS: Fifteen patients (average age 27.4 years) with complete brachial plexus palsy underwent full-length phrenic nerve transfer. The phrenic nerve was harvested from the thoracic cavity by means of video-assisted thoracic surgery and then transferred to the musculocutaneous nerve. Postoperative pulmonary functions were retrospectively analyzed. Patients underwent follow-up evaluation for 42 to 48 months; four patients were eventually lost to follow up. Although no patient experienced pulmonary problems following the surgery, all sustained varying degrees of diaphragmatic paralysis and elevation (for 1-1.5 intercostal spaces) on the surgically treated side as seen on chest x-ray films. Pulmonary functional parameters, including vital capacity, vital capacity in percentage of predicted values, residual volume, total lung capacity, forced vital capacity, and forced expiratory volume in 1 second, recovered to preoperative levels by 1 year postsurgery. In contrast, the postoperative maximal inspiratory pressure value was significantly decreased compared with the predicted values (average decrease approximately 20%) in all of the patients, even at 4 years after the surgery. CONCLUSIONS: In young patients with healthy lung function, unilateral phrenic nerve transection surgery can cause unilateral diaphragmatic paralysis and reduce the inspiration muscle force; however, most pulmonary function parameters gradually recover to preoperative levels within 1 year.

Adolescent↗
PubMed2003

A prospective evaluation of phrenic nerve conduction in multifocal motor neuropathy and chronic inflammatory demyelinating polyneuropathy.

The purpose of the study was to evaluate electrophysiologically phrenic nerve involvement in multifocal motor neuropathy (MMN) and chronic inflammatory demyelinating polyneuropathy (CIDP). The response latencies following phrenic nerve stimulation were increased in 11 of 14 (80%) patients in the CIDP group but in only 1 of 14 (8%) patients in the MMN group. The mean diaphragmatic compound muscle action potential (CMAP) was significantly lower in amplitude in the CIDP group compared to the MMN group and to a control group of 8 subjects (P < 0.001). There were no significant differences between the MMN and control groups. Only the reduction in CMAP amplitude correlated with the presence of restrictive lung function. Phrenic nerve conduction measurement should be performed more systematically, especially in CIDP and, when diaphragmatic CMAPs are reduced in amplitude, pulmonary function tests should be performed to look for a restrictive lung syndrome.

Adult↗