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PubMed1997

Perioperative assessment of respiratory compliance and lung volume in infants with congenital diaphragmatic hernia: prediction of outcome.

BACKGROUND/PURPOSE: Infants who have congenital diaphragmatic hernia (CDH) have high mortality and morbidity. The aim of this study was to determine the relative ability of the results of serial measurements of compliance of the respiratory system (CRS) and lung volume (functional residual capacity (FRC)) to predict poor outcome: death or oxygen dependency at 28 days. In addition, the authors wished to document the evolution of any lung function abnormalities during the perioperative period. METHODS: Daily measurements of CRS and FRC were made in the first week of life and subsequently during week 2 in 16 infants who had a median gestational age of 38 weeks and birth weight of 3.2 kg. RESULTS: Seven infants had a poor outcome: five died and two others remained oxygen dependent beyond 28 days. The infants who had a poor outcome were characterized on day 1 by a significantly lower CRS, but not FRC (P < .05). In comparison with results from day 1, the median CRS of the infants overall had significantly improved only by week 2 (P < .05), there was no such significant change in FRC with increasing postnatal age. At week 2, only the CRS results differed significantly between those infants who had and who did not have poor outcome (P < .05). CONCLUSION: The results of serial measurements of CRS, rather than FRC are the more useful predictor of outcome in infants who have CDH.

Female↗

PubMed2003

Congenital diaphragmatic hernia, kidney agenesis and cardiac defects associated with Slit3-deficiency in mice.

Slit3 along with Slit1 and Slit2 comprise the Slit family of proteins. The latter two proteins are known to be involved in axon guidance and cell migration during animal development. However, little is know about the functions of Slit3. We created a Slit3-deficient mouse model from an OmniBank ES cell line with a Slit3 allele trapped by insertional mutagenesis to analyze the in vivo functions of this protein. In this model, congenital diaphragmatic hernia is the most obvious phenotype. Herniation was found to be caused by a defective central tendon (CT) of the diaphragm that remained fused with the liver. Electron microscopic analyses of the defective CT revealed disorganized collagen fibrils that failed to form tight collagen bundles. The hearts of Slit3-deficient mice have an enlarged right ventricle. In addition, 20% of homozygous mice also showed a range of kidney defects that include unilateral or bilateral agenesis of the kidney and ureter, or varying degrees of renal hypoplasia. Thus, we concluded that Slit3 is involved in the development of multiple organ systems that include the diaphragm and the kidney. Slit3-deficient mice represent a genetic animal model for physiological and pathological studies of congenital diaphragmatic hernia.

Animals↗

PubMed2006

[Trauma mechanism and diagnosis of blunt diaphragmatic rupture].

BACKGROUND: Indirect diaphragmatic rupture (DR) is defined as acquired complete split of the diaphragm after blunt trauma and occurs in 1-5% of massively traumatized patients. The diagnosis is often difficult. However, particular trauma mechanisms and associated injuries may suggest the existence of DR. METHODS: A retrospective study was done of 21 consecutive patients from 1993 to 2004 at an university hospital. RESULTS: This study revealed a striking combination of DR with pelvic fractures (12/21, 57%). Of 19 polytraumatized patients, diagnosis was made initially in 13 (68%) and with a delay in six (32%). Right-sided injuries were common (8/21, 38%). Thus a 'protective' function of the liver does not exist. Diaphragmatic rupture can be missed in ventilated patients until extubation leads to herniation of abdominal organs into the thorax. CONCLUSIONS: Diaphragmatic rupture should be excluded in all severely abdominally traumatized patients, in particular those with concomitant pelvic fracture. Computed tomography with oral contrast medium is diagnostic in most cases. Access by laparotomy should be preferred after acute trauma, since additional intra-abdominal injuries are frequent.

Accidental Falls↗

PubMed1990

Contraction-dependent modulations in regional diaphragmatic blood flow.

Blood flow (Q) of the diaphragm was measured simultaneously with Doppler probes placed on diaphragmatic veins and an artery and by direct volumetric measurements obtained from cannulation of diaphragmatic blood vessels. The Doppler converting coefficients obtained were 6.27, 7.25, 4.21, and 41.07 ml.min-1.kHz-1 for left phrenic artery flow (Qpha), phrenic vein flow (Qphv), internal mammary vein flow (Qimv), and azygos vein flow (Qazv), respectively. The time course of Qpha, Qphv, Qimv, and Qazv after imposed patterns of diaphragmatic contraction was measured in nine anesthetized dogs. Each pattern consisted of various combinations of transdiaphragmatic pressure (Pdi), frequency of pacing (f), and duty cycle obtained by bilateral phrenic nerve stimulation. The dogs were prepared with chests open and loosely casted abdomens. Qpha, Qphv, Qimv, and Qazv were measured at rest (control, passive diaphragm, mechanical ventilation) and at two submaximal levels of stimulation (30 and 60% of Pdimax). The f was 10 or 30 cycles/min and the duty cycle was 0.25, 0.50, and 0.75. The results show 1) Qpha, Qphv, Qimv, and Qazv reached stable values (equilibration) after 30-36 s of pacing; 2) the steady Qpha, Qphv, and Qimv were linearly related to Pdi, and they were related by a parabolic function to duty cycle, whereas Qazv was not significantly affected by Pdi and increased linearly as a function of the duty cycle; 3) the diaphragmatic blood drainage was approximately 60% through the intercostal veins leading into the azygos trunk, 25% through the phrenic vein, and 15% through the internal mammary vein during pacing of the diaphragm at a duty cycle of 0.50 and 60% Pdimax; and 4) for a given pacing pattern, Qpha and Qphv increased with f, but Qimv and Qazv did not.

Animals↗

PubMed1998

The effects of prenatal intraamniotic surfactant or dexamethasone administration on lung development are comparable to changes induced by tracheal ligation in an animal model of congenital diaphragmatic hernia: studies of lung glycogen content, elastic fiber density, and collagen content.

BACKGROUND/PURPOSE: A new noninvasive therapeutic strategy, which consisted of prenatal intraamniotic administration of porcine surfactant or dexamethasone, was previously used to prevent the functional and structural immaturity of lungs associated with congenital diaphragmatic hernia (CDH), and its effects on lung development were comparable with the changes induced by tracheal ligation (TL). The purpose of this study is to verify if this novel therapeutic modality has any effect in the elevated concentration of lung glycogen and altered contents of lung elastic fiber and collagen promoted by CDH. METHODS: A pilot study was performed to investigate in the rabbit model if the infused drugs in the amniotic cavity were aspirated by the CDH and non-CDH fetuses, and if there was correspondence between lung immaturity and high glycogen concentration in lung tissue. Experimental groups consisted of 50 pregnant rabbits that underwent surgery on gestational day 24 or 25 to create left-sided diaphragmatic hernias in 56 fetuses, which were divided in groups according to the procedures: CDH (n = 12), CDH plus TL (n = 16), CDH plus intraamniotic administration of Curosurf (40 mg, n = 12), and CDH plus intraamniotic administration of dexamethasone (n = 16). On gestational day 30, the fetuses were delivered by cesarean section, and 28 normal unoperated fetuses served as controls. The lungs were weighed and submitted to biochemical determination of glycogen, morphometric evaluation of elastic fibers, and colorimetric analysis of collagen. RESULTS: In all CDH and non-CDH fetuses of the pilot study, the amniotic content was massively aspirated into the lungs and trachea. There was an increase in lung glycogen content of fetuses at 24 days' gestation in comparison with 20-day gestational age fetuses, followed by a decrease in the near full-term fetuses. In the fetuses of the experimental groups, CDH decreased the lung weight to body weight ratios of lungs ipsilateral to the hernia. These changes were reversed by TL but not by intraamniotic administration of surfactant or dexamethasone. Lung glycogen concentrations in the lungs of CDH fetuses were significantly higher than those in the control group. These changes were reversed by intraamniotic administration of surfactant but not by dexamethasone administration or TL. In the lungs ipsilateral to the hernia, surfactant administration promoted a significant decrease in glycogen content to levels lower than control lungs. CDH promoted a decrease in the linear density of elastic fibers in both lungs, ipsilateral and contralateral to the hernia. This alteration was partially corrected by TL and surfactant administration, although dexamethasone administration had no effect. The concentrations of collagen in both lungs were increased significantly by CDH, and these alterations could not be reversed by TL. In the lungs ipsilateral to the hernia, intraamniotic administration of surfactant or dexamethasone promoted a significant decrease in the lung concentration of collagen but not to control levels. CONCLUSIONS: The positive effects of intraamniotic surfactant or dexamethasone administration on lung maturity of fetuses with CDH were observed. This therapy may be a substitute for TL.

Animals↗

PubMed2006

Prevention of heart failure in the management of congenital diaphragmatic hernia by maintaining ductal patency. A case report.

Congenital diaphragmatic hernia is a rare entity in childhood carrying a high mortality rate of 30% to 50%. Ipsilateral pulmonary hypoplasia, increased pulmonary vascular resistance, and potential cardiac failure complicate early postnatal life. Surgical correction can either be performed on the first day of life or be deferred to a time after stabilization of the infant. Our patient presented with a left-sided Bochdalek's hernia containing large and small bowel. She required intubation and resuscitation on day 1 of life, and surgical repair had to be postponed. Further respiratory deterioration required commencement of inhaled nitric oxide and high-frequency ventilation. Pulmonary artery pressure rose to suprasystemic level. Closure of the ductus arteriosus on day 8 resulted in imminent right-sided heart failure. Commencement of alprostadil (prostaglandin E1) reopened the ductus and stabilized the patient. Surgical repair was successful 3 days later. Alprostadil should be considered as an important component of therapy in severe cases of congenital diaphragmatic hernia, where deterioration of right-sided heart function occurs.

Ductus Arteriosus, Patent↗

PubMed1987

The prone position improves arterial oxygenation and reduces shunt in oleic-acid-induced acute lung injury.

The arterial oxygen tension (PaO2) may increase when patients with the adult respiratory distress syndrome are turned from supine to prone. We sought to reproduce this observation in dogs with acute lung injury to study the physiologic mechanism by which the improvement in oxygenation might occur. Twenty anesthetized dogs were ventilated with a constant tidal volume (20 ml/kg) of 100% oxygen. Oleic acid (0.09 ml/kg) was injected into the right atrium while rotating the animals through 360 degrees in 4 stages. Animals in Group I (n = 5) remained supine for 10 to 120 min until the supine PaO2 fell below 200 mm Hg. Those in Group II (n = 4) were kept prone during this period. Dogs in Groups I and II were then turned supine or prone every 30 min 5 times. Cardiac output and pulmonary vascular pressures, functional residual capacity (helium dilution), and regional diaphragmatic motion (determined by dorsal and ventral diaphragmatic markers relative to markers on the chest wall seen on lateral chest radiographs taken at FRC and at end-inspiration) were obtained in each position. Eleven dogs were kept supine (Group III, n = 6) or prone (Group IV, n = 5) for 2 h after oleic acid infusion, after which intrapulmonary shunt (Qs/QT) and ventilation-perfusion heterogeneity were measured in the supine and prone positions using the multiple inert gas elimination technique.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMed1978

[Pulmonary gas exchange in newborns with congenital diaphragmatic hernia (author's transl)].

In 20 newborns with congenital diaphragmatic hernia the state of the pulmonary function was studied through the blood gas values (PO2 and PCO2 on breathing air and 100% oxygen spontaneously or with mechanical ventilation). The group of survivors presented a normal or slightly altered pulmonary function, whilst in the group that died the pulmonary function was severely altered. Up to now, and in accordance with the results obtained, none of the proposed hypothesis (pulmonary atelectasis, extra-pulmonary right-to-left shunt, pulmonary hypoplasia) explain this alteration in a satisfactory manner. From the prognostic point of view, if the levels of gases are spontaneously normal or with administration of oxygen and/or assisted, ventilation a level of PO2 higher than 230 and of PCO2 lower than 70 is obtained, prognosis is excellent. If these levels are not obtained the prognosis is nearly always fatal and the value of the intervention questionable.

Blood Gas Analysis↗

PubMed1988

Effect of lung inflation on diaphragmatic shortening.

The effect of lung inflation on chest wall mechanics was studied in 11 vagotomized pentobarbital sodium-anesthetized dogs. Diaphragmatic shortening (percent change from initial length at functional residual capacity, %LFRC) and transdiaphragmatic pressure swings (delta Pdi) were compared with control values over a range of positive-pressure breathing that produced a maximum increase in lung volume to 40% of inspiratory capacity. There was no change in the electromyogram of the diaphragm or parasternal intercostals during positive-pressure breathing. delta Pdi and tidal volume (VT) fell to 52 +/- 3.3 and 42.5 +/- 5% (SE) of control. This was associated with a reduction in the initial resting length of 13 +/- 1.9 and 21 +/- 2.2%LFRC (SE) in the costal and crural diaphragms, respectively. Tidal diaphragmatic shortening, however, decreased to 66 +/- 7 and 57 +/- 7 and the mean velocity decreased to 78 +/- 10 and 63 +/- 8% (SE) of control for the costal and crural diaphragms, respectively. We conclude that the reduction in diaphragmatic shortening is the main determinant of the reduced delta Pdi and VT during lung inflation and relate this to what is currently known about diaphragmatic contractile properties.

Animals↗

PubMed2005

Noninvasive proportional assist ventilation and pressure support ventilation during arm elevation in patients with chronic respiratory failure. A preliminary, physiologic study.

BACKGROUND: It has been shown that upper limbs activity increases the respiratory workload in patients with chronic respiratory failure (CRF). The object of the present study was to investigate whether, in these patients: (i) noninvasive positive pressure ventilation (NPPV) could sustain the inspiratory muscles to meet the greater ventilatory demand during upper limbs activity with the arm elevation test (AE); (ii) proportional assist ventilation (PAV) might be superior to pressure support ventilation (PSV) during AE, because of its potential more adaptable response to sudden changes in the ventilatory pattern. METHODS: The study was performed in the pulmonary function laboratory of the Pulmonary Division in Verona General Hospital, Verona, Italy. We studied 8 male patients with CRF due to chronic obstructive pulmonary disease (COPD). Each patient received 2 treatment in random order with a crossover design: spontaneous breathing (SB), SB with AE, either PSV or PAV without and with AE, SB without and with AE, either PSV or PAV without and with AE. We measured: lung function tests, lung mechanics, ventilatory pattern and diaphragmatic effort (pressure time product, PTP(di)). RESULTS: (i) AE increases minute ventilation (+14%) and PTP(di) (+64%); (ii) ventilatory support, both with PSV and PAV unloads the diaphragm both at rest (PTP(di) -77% and -54%, respectively) and during arm elevation (PTP(di) -54% and -44%, respectively). CONCLUSIONS: PAV and PSV unloads the diaphragm in patients with CRF due to COPD both during SB and AE; PAV can be more efficient than PSV in assisting the diaphragm during AE in producing a greater level of minute ventilation for a similar rise in PTP(di) compared to PSV. Noninvasive ventilatory support should be considered in rehabilitation programs for training of upper limbs activity.

Aged↗

PubMed1997

Role of KATP channels on modulating diaphragmatic microvascular flow during hemorrhagic hypotension.

The effects of glibenclamide (GLB), a specific blocker of ATP-sensitive potassium (KATP) channels, and tetraethylammonium (TEA) on modulating the regulation of diaphragmatic microcirculation were assessed in anesthetized mechanically ventilated rats. With bicarbonate-buffered Ringer solution continuously suffusing the left hemidiaphragm, microcirculatory blood flow was recorded by laser-Doppler flowmetry (QLDF). Hemorrhagic hypotension (HH) was induced via bleeding into a pressure reservoir. Five sets of experiments were performed. In set 1 (n = 6), the vasodilator effect of diazoxide (3 x 10(-4) M) was abolished after a 30-min suffusion with GLB, whereas the vasodilator effect of sodium nitroprusside (3 x 10(-6) M) remained the same. In set 2 (vehicle + HH; n = 23), a stepwise reduction in systemic arterial blood pressure (ABP) induced two distinct patterns of microvascular responses. Regulation of QLDF could be observed in pattern A animals in a range of ABP from 113 to 52 mmHg, whereas QLDF in pattern B animals rose progressively with declining ABP. In set 3 (GLB + HH; n = 17), baseline values of QLDF were not significantly affected after a 30-min suffusion of GLB (10(-5) M). During HH, two microvascular patterns similar to those in set 2 were observed. GLB significantly potentiated the reduction in QLDF in pattern A animals. In contrast, GLB had no effect on QLDF in pattern B animals. In set 4 (TEA + HH; n = 17), similar microvascular responses, compared with the vehicle group, were observed during HH after a 30-min suffusion of TEA (2 x 10(-3) M). In set 5 (n = 5), baseline values of QLDF were not significantly altered during sham hypotension. We conclude that 1) KATP channels are functional but not active in the resting diaphragmatic microcirculation and 2) KATP channels can modulate regulation of the microcirculation in the resting diaphragm during HH.

Adenosine Triphosphate↗

PubMed1975

Pulmonary problems in Duchenne muscular dystrophy. Diagnosis, prophylaxis, and treatment.

A number of pulmonary problems may complicate muscular dystrophy. Respiratory function, however, can be increased by instruction in diaphragmatic breathing. When patients effectively use their diaphragms during respiration, less muscular work is required for adequate ventilation. Additionally, assistive techniques such as postural drainage, chest percussion and vibration, and IPPB contribute to an ongoing program of respiratory care. Ten children with Duchenne muscular dystrophy underwent pulmonary function studies before, during, and after a three-month period of such respiratory therapy. Comparison of respiratory function before and after treatment indicates that such treatment is useful in increasing pulmonary function. The major goal of pulmonary care in the treatment of the patient with muscular dystrophy is the maintenance of respiratory homeostasis through beathing exercises and training in the use of various breathing aids, thus enabling the patient to lead as active and comfortable a life as possible within the limits imposed by his evolving respiratory problem.

Adolescent↗

PubMed1988

Human diaphragmatic endurance during different maximal respiratory efforts.

1. This study assessed human diaphragmatic endurance under two conditions: during maximal inspiratory efforts (with minimal elevation of abdominal pressure) and during maximal expulsive efforts (with minimal elevation of pleural pressure). Performance was compared with that of the flexors of the elbow. 2. In series of eighteen sustained maximal efforts begun near functional residual capacity the decline in trans-diaphragmatic pressure was significantly greater during the expulsive than the inspiratory efforts (P less than 0.01). Diaphragmatic endurance was greater than that of the flexors of the elbow. 3. Electromyograms recorded during maximal and submaximal expulsive contractions indicated that the relatively rapid decline in abdominal pressure during the series of expulsive contractions reflected fatigue of the diaphragm rather than the abdominal muscles. Supramaximal phrenic nerve stimulation was used to check that complete activation of the phrenic motoneurone pool could be achieved during series of maximal expulsive efforts. 4. It is concluded that the reduced endurance capacity of the diaphragm during expulsive efforts did not reflect peripheral failure of the abdominal muscles or an inability to activate the diaphragm fully during those maximal efforts. 5. The deterioration in diaphragmatic performance when abdominal pressure is elevated may be due to an impairment of muscle perfusion.

Abdomen↗

PubMed1993

[Long-term follow-up in patients operated on for aortic coarctation. The echo-Doppler and MRI assessment of left ventricular function and the transisthmic gradient].

BACKGROUND: Hyperdynamic left ventricular function and increased left ventricular mass has been recently reported in the long-term follow-up of patients after successful repair of aortic coarctation (AoCo). METHODS: We studied 35 patients, mean age 22.7 years (range 1-47), following repair of AoCo in order to evaluate: 1) left ventricular mass and systolic function by M-mode echocardiography in comparison with 20 healthy control subjects; 2) the prevalence of systemic hypertension; 3) systolic blood pressure and the trans-isthmic gradient by CW Doppler at rest and after exercise; 4) subjects with a hypertensive response and/or with a significant trans-isthmic gradient during exercise, correlating such parameters with indexes of left ventricular function and the ratio of aortic isthmus/aortic diaphragmatic diameters (AOI/AOD) by means of Magnetic Resonance (MR). At the time of operation, mean age was 12.4 years (range 1 mo-40 yrs) and the follow-up period was 10.1 years (range 6 mo-26 yrs). RESULTS: Left ventricular mass index (Mi) was significantly greater in comparison with that of the controls (96.5 +/- 25 vs 71.5 +/- 16.6 g/m2; p < 0.001); the mean velocity of circumferential shortening (mVCFc) was increased (1.4 +/- 0.25 vs 1.2 +/- 0.16 circ/s; p < 0.005); the end systolic meridional stress (ESS) was decreased (37.3 +/- 11.1 vs 47.9 +/- 13.1 g/cm2; p < 0.005) while the peak systolic meridional stress (PSS) was not significantly different in the two groups. Fourteen out of 35 patients (40%) showed an exaggerated mVCFc for the level of ESS, which indicates an increased inotropic state. Hypertension at rest was present in 10 patients (28%). Mean age at the time of operation of the hypertensive group was higher than that of the normotensive one (21.4 +/- 10 vs 8.9 +/- 8.6 yrs; p < 0.001). All patients showed a small systolic gradient across the side of coarctation repair at rest (mean 13.1 mmHg; range 0-30). The exercise test was stopped in 5 patients because of hypertension (> 250 mmHg); 24 patients (80%) showed an exercise-induced hypertension. The mean gradient at maximal exercise was 25.9 mmHg (range 0-52); 6 patients (20%) developed a diastolic gradient. With MR it was possible to evaluate the anatomy of the aortic arch and the descending aorta in all cases. The mean ratio AOI/AOD was 0.81 (range 0.63-1). The age at the time of operation showed a positive correlation with the systolic blood pressure (r = 0.63; p < 0.001) and with Mi (r = 0.45; p < 0.005). The systolic blood pressure and the gradient at maximal exercise also showed a positive correlation (r = 0.40; p < 0.01). CONCLUSIONS: In the long-term follow-up of patients after successful coarctation repair there are persistent alterations of left ventricular function with hypertrophy, hyperkinesia and increased inotropic state. Hypertension at rest and after exercise could persist despite good surgical results.

Adolescent↗

PubMed1997

The involvement of ATP-sensitive potassium channels in beta 2-adrenoceptor agonist-induced vasodilatation on rat diaphragmatic microcirculation.

1. The effects of glibenclamide (GLB), a blocker of ATP-sensitive potassium (KATP) channels, on diaphragmatic microcirculation in male Sprague-Dawley rats were assessed under basal conditions and after beta 2-adrenoceptor-agonist stimulation. In addition, forskolin was used to bypass beta-adrenoceptors and GTP-binding proteins (G-protein) to explore the possible mechanism of GLB effects. For comparison, the relationships between KATP channel activity and cyclic GMP-mediated vasodilator responses to acetylcholine (ACh) and sodium nitroprusside (SNP) were also assessed. 2. Male Sprague-Dawley rats were anaesthetized with urethane and mechanically ventilated. The left hemi-diaphragm of each rat was prepared and microvascular blood flow (QLDF) was recorded with laser-Doppler flowmetry during continuous superfusion with bicarbonate-buffered, prewarmed Ringer solution. The drugs were topically applied to the surface of the hemi-diaphragm. 3. Salbutamol (0.32-32 microM), terbutaline (0.32 microM-0.32 microM) and forskolin (0.32-10 microM) each elicited a concentration-dependent increase in QLDF. 4. Baseline microvascular blood flow was unaffected by a 30 min suffusion of 1 microM GLB (295 +/- 51 mV vs 325 +/- 62 mV. P = 0.738). 5. The vasodilator response elicited by salbutamol (0.32 microM, 1 microM and 3.2 microM and 10 microM), was significantly attenuated by a 30 min superfusion with 1 microM GLB; this salbutamol-induced vasodilatation was mediated via an interaction with beta-adrenoceptor receptors, as in other experiments it was greatly inhibited by 30-min superfusion with propranolol (10 microM). 6. Similarly, following 30-min superfusion with GLB (1 microM), the terbutaline (1 microM, 3.2 microM and 10 microM)-induced vasodilator response was almost abolished and the vasodilator responses induced by incremental concentrations of forskolin (0.32 microM, 1 microM and 3.2 microM) were also significantly attenuated. 7. Cromakalim (1.5 microM, 3 microM and 3.2 microM) produced an increase of QLDF in a dose-dependent manner, which was virtually abolished by GLB (1 microM). In contrast, the vasodilator responses induced by acetylcholine (32 microM, 0.1 mM, and 0.32 mM) or sodium nitroprusside (3.2 microM, 10 microM and 20 microM) were independent of GLB (1 microM). 8. In conclusion, KATP channels may be functional, but tonically inactive in the resting diaphragmatic microcirculation and the vasodilator effect of beta 2-adrenoceptor agonists may be partly mediated by KATP channels; the activation of KATP channels may involve the accumulation of cyclic AMP in vascular smooth muscle cells.

Adenosine Triphosphate↗

PubMed2005

Late-presenting congenital diaphragmatic hernia.

BACKGROUND: Late-presenting congenital diaphragmatic hernia (CDH) is a rare subset of CDH, most of the information derived from small series or case reports. The aim of this study was to document the clinical manifestations of late-presenting CDH using a large multicenter database. METHODS: Information about late-presenting CDH (diagnosed at later than 30 days of age) was identified from the database of the CDH Study Group (3098 cases collected during 1995-2004) and reviewed retrospectively. RESULTS: Seventy-nine cases (2.6%) from 30 centers met the inclusion criteria. Seven cases had a Morgagni hernia. There were 50 males (65%) and 27 females (35%). The mean age at diagnosis was 372 days (32 days to 15 years). Major associated anomalies (10 cardiac and 7 chromosomal abnormalities) were identified in 12 cases (15%). Presenting symptoms were respiratory in 20 (43%), gastrointestinal in 15 (33%), both in 6 (13%), and none (asymptomatic) in 5 (11%). The hernia was left-sided in 53 (69%), right-sided in 21 (27%), and central or bilateral in 3 (4%). Patients with gastrointestinal symptoms invariably had left-sided hernias (n = 19), whereas patients with respiratory symptoms (n = 24) seemed equally likely to have right- or left-sided lesions. A primary repair without patch was done in all cases with 100% survival. CONCLUSIONS: Presenting symptoms of late-onset CDH can be respiratory or gastrointestinal, but presentation with gastrointestinal problems was more common in left-sided hernias, whereas respiratory symptoms predominated in right-sided lesions. The prognosis is excellent once the correct diagnosis is made.

Adolescent↗

PubMed1993

Changes in diaphragmatic EMG activity during sleep in space.

It remains unknown how increased upper airway resistance (UAR) during sleep could be a function of gravity. We therefore conducted quantitative evaluation of the gravitational influence on diaphragmatic EMG activity (EMGdi) in an astronaut to estimate the effect of UAR in space. EMGdi was recorded by paired surface electrodes on the ground (control, C) and abroad a short-term space mission (space, S) for 30 consecutive h. Mean EMGdi recorded during quiet breathing in wakefulness was assigned the value of 100. EMGdi in C was significantly enhanced in all sleep stages compared with that while awake in the supine position (mean +/- SD, 230 +/- 23.2% in non-rapid eye movement (non-REM) Stage II, 233 +/- 13.8 in slow-wave sleep, and 233 +/- 40.0 in REM sleep versus 100 +/- 17.3 in wakefulness, p < 0.001). In contrast, there was no statistical difference in EMGdi in S between awake and any non-REM sleep stage (mean +/- SD, 100 +/- 20.5% in wakefulness versus 103 +/- 16.9 in non-REM Stage II and 100 +/- 14.8 in slow-wave sleep; NS). However, EMGdi in REM sleep in S was statistically greater (132 +/- 28.3%) than that during wakefulness or any other sleep stage in space (p < 0.001). Therefore, gravity may play a much more significant role in the normal healthy human in the increased upper airway resistance during sleep than the relative atonia of the upper airway muscles.

Analysis of Variance↗

PubMed2000

Treatment of severe congenital diaphragmatic hernia by fetal tracheal occlusion: clinical experience with fifteen cases.

OBJECTIVE: Our purpose was to determine whether prenatal tracheal occlusion improves survival in a selected population of fetuses affected by severe congenital diaphragmatic hernia. STUDY DESIGN: Fetuses with isolated congenital diaphragmatic hernia were selected as candidates for fetal intervention by specific criteria designed to predict a 90% mortality rate with conventional postnatal treatment. RESULTS: Fifteen fetuses underwent tracheal occlusion with 5 survivors (33%). Two fetuses were lost to early preterm labor. In 13 mothers, postoperative gestation ranged from 19 to 68 days, with a mean duration of pregnancy after tracheal occlusion of 38 days. The 5 survivors were hospitalized for an average of 76 days. Despite dramatic lung growth in some fetuses after tracheal occlusion, intensive management was required, and most deaths were caused by respiratory insufficiency. CONCLUSION: Prenatal tracheal occlusion can result in impressive lung growth in a subset of fetuses with severe congenital diaphragmatic hernia. However, survival remains compromised by pulmonary functional abnormality and the consequences of prematurity.

Child Development↗