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PubMed1982

Phrenic nerve function after pneumonectomy.

Using surface electrodes over the lower chest wall, we measured the phrenic nerve conduction time, ie, the time interval between the stimulation of the phrenic nerve in the neck and the onset of the diaphragmatic muscle action potential, in ten patients who had undergone pneumonectomy several years before (mean, eight years) and in 31 control subjects (bilaterally in 19 of them). The mean (+/- SD) value in the control subjects was 7.0 (+/- 0.9) msec, and no value exceeded 10 msec. All the values obtained in the patients were within the control range. We concluded that phrenic nerve function remains normal after pneumonectomy. This method appears to be the most effective means of identifying phrenic nerve involvement in these patients.

Adult↗
PubMed1986

[Technics for the functional evaluation of the thoracic cage].

A study of lung volumes offers an overall index of thoracic mobility. The techniques of magnetometry and respiratory plethysmography by induction allow studies of thoracic wall movements to be separated into two compartments by measuring thoracic and abdominal movements. These techniques enable a quantitative evaluation of thoraco-abdominal incoordination seen notably in patients with chronic airflow obstruction and in cases of respiratory muscle fatigue. Similar information is obtained by measuring variations in inspiratory pleural and abdominal pressure, using oesophageal and gastric balloons. The maximal force of respiratory muscles is an important index of the functional reserve at a patient's disposal and may be assessed by measuring maximal inspiratory and expiratory pressures at the mouth against an occlusion. Diaphragmatic force is assessed by the maximal trans-diaphragmatic pressure. Respiratory muscle fatigue appears when their contraction is sustained above a certain threshold of tension and duration. This phenomenon may be detected by a diminution of maximal pressures. For example, the fatigue of inspiratory muscles is accompanied by a fall of maximal inspiratory and trans-diaphragmatic pressures. The fatigue process can also be detected early by changes in the pattern of the diaphragmatic electromyogram. The principles and limitations of different techniques of assessment of respiratory muscle fatigue are analysed. The use of one or several of these techniques accompanied by an awareness of the clinical signs of respiratory muscle fatigue ought to enable an early detection of this condition.

Humans↗
PubMed1993

[A case of constrictive pericarditis--adjuvant techniques of operation and evaluation of the perioperative cardiac function].

A 43-year-old male diagnosed as constrictive pericarditis with dyspnea, fatigability and substantial pericardial calcification on chest roentgenogram underwent pericardiectomy through median sternotomy. The heavily calcified pericardium which was adherent to the anterior and diaphragmatic surface of the heart was successfully resected by the combined use of ultrasonic surgical aspirator (CUSA) and argon beam coagulator (ABC). Intraoperative bleeding was minimal because the adhesion between the pericardium and myocardium, coronary arteries or inferior vena cava were easily dissected with CUSA. Intraoperative hemostasis was also satisfactory with ABC. Perioperative measurements of right ventricular ejection fraction were also effective in evaluating the right ventricular function.

Adult↗
PubMed1994

Accurate method to study static volume-pressure relationships in small fetal and neonatal animals.

We designed an accurate method to study respiratory static volume-pressure relationships in small fetal and neonatal animals on the basis of Archimedes' principle. Our method eliminates the error caused by the compressibility of air (Boyle's law) and is sensitive to a volume change of as little as 1 microliters. Fetal and neonatal rats during the period of rapid lung development from day 19.5 of gestation (term = day 22) to day 3.5 postnatum were studied. The absolute lung volume at a transrespiratory pressure of 30-40 cmH2O increased 28-fold from 0.036 +/- 0.006 (SE) to 0.994 +/- 0.042 ml, the volume per gram of lung increased 14-fold from 0.39 +/- 0.07 to 5.59 +/- 0.66 ml/g, compliance increased 12-fold from 2.3 +/- 0.4 to 27.3 +/- 2.7 microliters/cmH2O, and specific compliance increased 6-fold from 24.9 +/- 4.5 to 152.3 +/- 22.8 microliters.cmH2O-1.g lung-1. This technique, which allowed us to compare changes during late gestation and the early neonatal period in small rodents, can be used to monitor and evaluate pulmonary functional changes after in utero pharmacological therapies in experimentally induced abnormalities such as pulmonary hypoplasia, surfactant deficiency, and congenital diaphragmatic hernia.

Air Pressure↗
PubMed2004

Morgagni hernia in adults: results in 7 patients.

OBJECTIVE: Morgagni's hernia is a relatively uncommon diaphragmatic hernia with a potential for considerable morbidity, if the diagnosis is delayed or missed. This review of cases of Morgagni's hernia was undertaken in order to emphasize methods of diagnosis and treatment. METHODS: From 1992 through 2002, seven patients with Morgagni's hernia (5 right, 2 left) were surgically treated at our hospital. We investigated the patients preoperatively including chest roentgenogram, chest CT scan, and contrast studies of the upper gastrointestinal tract. Operative repair was accomplished with the transabdominal or transthoracic approach. Basic spirometric tests had been carried out on patients presented for elective surgery. RESULTS: The majority of patients experienced dyspnea and two patients presented with acute abdomen due to peritonitis. Diagnosis for Morgagni's hernia was made preoperatively in all but one patient. In cases with uncertain diagnosis or peritonitis, a transabdominal approach was preferred. One patient had died of septic multi-organ failure in the early postoperative course. Following elective repair of Morgagni's hernia, improvement in basic spirometric values was seen. CONCLUSIONS: We conclude that repair for Morgagni's hernia can be performed safely and effectively by using different surgical approaches. The risk of progression and incarceration makes clinical awareness, early diagnosis, and surgical treatment warranted. Improvement in lung function can be expected postoperatively.

Aged↗
PubMed1987

Metabolic support during coronary reperfusion.

The limitation of infarct size by thrombolysis could potentially be improved by an early metabolic intervention. We therefore evaluated the effects of a 48-hour infusion of glucose-insulin-potassium (GIK) in patients with anterior infarctions. Seventeen patients were randomized to receive intravenous GIK (n = 10) or placebo (n = 7). All patients additionally received streptokinase. Changes in left ventricular function were assessed by comparing the global ejection fractions and the regional infarct area ejection fractions of the first ventriculogram with the 10-day second ventriculogram. There was a significantly greater improvement in the global ejection fraction of patients receiving GIK (increases 0.07 +/- 0.04) than in those randomized to placebo (decreases 0.08 +/- 0.04) (p less than 0.02). There was also a much greater improvement in the area ejection fractions of the group receiving GIK vs the group receiving placebo in the anterolateral (increases 0.24 +/- 0.07 vs decreases 0.02 +/- 0.04 [p less than 0.02]) and diaphragmatic (increases 0.08 +/- 0.08 vs decreases 0.17 +/- 0.05 [p less than 0.005]) segments. Thus in patients with anterior infarctions receiving streptokinase, GIK improves ventricular function and reduces the size of the segmental wall motion abnormality.

Adult↗
PubMed1997

Tracheal ligation: the dark side of in utero congenital diaphragmatic hernia treatment.

Currently there are two in utero procedures that have been proposed for the treatment of Congenital diaphragmatic hernia (CDH); reduction of the herniated viscera with repair of the diaphragmatic defect (CDH repair) and stimulation of lung growth by ligation of the fetal trachea (CDH + TL). Recent studies have shown that CDH + TL may result in a significant surfactant deficiency. The aim of this study was to compare the postnatal lung function of these two interventions using the fetal lamb model of CDH. CDH was created in 14 lambs at 78 days' gestation. At 110 days, seven lambs had their trachea ligated through a transverse neck incision and seven had repair of their diaphragmatic defect via a left subcostal incision. At term the lambs were instrumented with the umbilical circulation intact, then delivered and ventilated to a standard protocol for 4 hours. Pulmonary hemodynamics and blood gas levels were measured and compared every 30 minutes. Four lambs in the CDH repair group and five lambs in the CDH + TL group survived to be studied. After the initial data were analyzed, a further group of CDH + TL lambs (n = 4) were studied. In this group a replacement dose of surfactant (Infasurf, Ony Inc, Buffalo, NY) was administered. These initial results cast doubt on tracheal ligation as an in utero therapy for CDH, and indicate that the lung produced by this intervention is not physiologically normal as previously thought. However, the function of these lungs can be normalized if the surfactant deficiency is corrected. If this improvement can be maintained and there is recovery of the endogenous surfactant system, then in utero tracheal ligation may become a viable treatment for fetal CDH.

Analysis of Variance↗
PubMed1996

Intraoperative phrenic nerve monitoring in cardiac surgery.

BACKGROUND: Left hemidiaphragmatic paralysis due to phrenic nerve lesion is a frequent complication of hypothermic cardiopulmonary bypass. Although this is believed to be caused by cold injury to the phrenic nerve, its exact cause is still not clear. STUDY OBJECTIVE: To assess feasibility, safety, and usefulness of intraoperative phrenic nerve function monitoring. SETTING: Elective cardiac surgery in a university hospital. PATIENTS: Consenting patients scheduled for myocardial revascularization surgery with the use of the left internal mammary artery. DESIGN: Intraoperative monitoring of compound diaphragmatic action potentials (CDAPs) through transcutaneous stimulation of phrenic nerves. INTERVENTIONS: Patients were divided in two groups. Group 1 received intracoronary cold St. Thomas's solution as the only cardioplegic method. Group 2 received topical cardiac cooling with ice-cold solutions in addition to intracoronary cardioplegia. RESULTS: In all group 1 patients, function of phrenic nerves was maintained throughout the surgical procedure. Group 2: in two patients, bilateral, and in one patient, left phrenic nerve conduction was abolished after submersion of the heart in ice-cold solution. In two of them, the action potential of the left hemidiaphragm was absent by the end of surgery. In one, nerve conduction recovered with rewarming of the patient. DISCUSSION: Intraoperative monitoring of CDAP was safe and easily obtained in the intraoperative setting. It allowed us to observe changes in phrenic nerve conduction occurring during surgery and as a result of cold cardioplegia. Cryogenic lesion of phrenic nerve might explain our findings. However, nerve ischemia cannot be ruled out and it may worsen axonal damage or delay its recovery. COMMENT: This monitoring method allowed us to predict postoperative diaphragmatic dysfunction. Also, surgeons can be warned of the damaging effects of excessive cooling of the pericardium and surrounding structures; thus, preventive measures can be taken.

Action Potentials↗
PubMed1993

Comparisons among external resistive loading, drug-induced bronchospasm, and dense gas breathing in cats: roles of vagal and spinal afferents.

In anesthetized cats, breathing spontaneously, increase in lung resistance (RL) was induced by either external resistive loads (ERL) or internal loading produced by dense gas breathing (sulfur hexafluoride, SF6) or serotonin (5-HT)-induced bronchoconstriction. The 3 test agents were used in each animal. Arterial blood gases were maintained in the normal range. Ventilatory and cardiovascular responses were studied in 3 groups of animals: intact, vagotomized, or spinalized at C8 level, a condition that preserved diaphragmatic afferents. In intact or spinal animals, ERL as well as SF6 inhalation lengthened the inspiratory and/or the expiratory periods, whereas 5-HT injections elicited rapid shallow breathing. The changes in ventilatory timing with either type of load were not observed in vagotomized cats. In all animals, ERL breathing or 5-HT injections increased the moving-time average of diaphragmatic EMG measured at constant time (Edi 0.1 and 0.5 secs), but this was not observed during SF6 inhalation, a condition in which the magnitude of RL increase was less than in the 2 other situations. The changes in systemic arterial blood pressure and/or cardiac frequency were mostly associated with 5 HT-induced bronchoconstriction. They persisted in spinalized cats, but were not observed or reversed in vagotomized ones. These observations demonstrate that vagal afferents play a major role in the changes in ventilatory timing and cardiovascular function in response to both external or internal moderate resistive loading. The existence of Edi changes in the 3 groups of cats suggests also that diaphragmatic afferents, preserved in both situations, are involved in this response.

Abdominal Muscles↗
PubMed2005

[Unilateral diaphragmatic paralysis in a diabetes patient].

Bilateral or unilateral diaphragmatic paralysis may be caused by motor neuron or muscle disease. Diabetic neuropathy, which is a common complication in diabetic patients, has a wide range of clinical manifestations. This is a case history of a 52 year old diabetic woman hospitalized with new paralysis of the right diaphragm. A thorough evaluation revealed no reason for diaphragmatic paralysis, other than diabetic neuropathy. A six month follow-up revealed significant clinical improvement. This article includes a summary of the literature, discussing the relationship between diabetes mellitus and diaphragmatic paralysis.

Diabetes Complications↗
PubMed1979

[The functional result of surgery of hiatus hernia (author's transl)].

The authors study 50 case records of hiatus hernia operated according to the modified technic of Nissen or Toupet. There was no anatomical relapse, but they observed in five cases an imperfect functional result. In three cases, this imperfect result with dysphagia and esophageal dilatation, is transient and is due to restoration of the sphincter. In two other cases, the dysphagia persisted for years after the operation. The latter cases were in young subjects with digestive dystonia. From these cases, the authors distinguish hernias due to ageing and those due to deterioration of the meso-esophagus, easily curable surgically, and hernias in young subjects due to a neuro-hormonal disturbance where surgical reconstruction of the sphincter does not produce the expected functional cure.

Adult↗
PubMed1985

A behavioral analysis of diaphragmatic breathing and its effects on peripheral temperature.

Three young women volunteers were trained through instructional feedback in two breathing procedures: diaphragmatic, derived from Eastern meditative techniques, and thoracic, involving opposite maneuvers. A single-subject reversal design was employed. Physiograph recordings of diaphragmatic expansion and mouth breathing provided the basis for feedback. Peripheral (digital) temperature was time-sampled at 1-min intervals and linear regression lines were fitted to the data. Temperature decreased throughout "normal" (baseline) breathing, probably due to warm outdoor and cool indoor temperatures. For two subjects, temperature during diaphragmatic breathing was generally stable; temperature during thoracic breathing showed significant decreases and did not differ from normal breathing. Within-session reversals showed dramatic changes in temperature as a function of breathing technique, which were maintained at follow-up, for these subjects. Temperature was more labile and decreased regardless of breathing procedure for the third subject. These data support a relationship between respiratory and vasomotor activity, and suggest that breathing strategy may be an uncontrolled variable in temperature biofeedback. It is further suggested that diaphragmatic breathing may facilitate temperature biofeedback or other types of relaxation training.

Adult↗
PubMed1959

Esophageal hiatal hernia; some aspects of surgical treatment.

Patients with esophageal hiatal hernia often have an array of distressing complaints and physical signs that are difficult to interpret. Physiologic and anatomic studies of the gastroesophageal area in the region of the esophageal hiatus of the diaphragm indicate the existence of a three-in-line sphincter group, consisting of the inferior esophageal constrictor, diaphragmatic pinchcock and cardioesophageal junction. These mechanisms, acting in unison, prevent regurgitation in normal persons.It also can be deduced from clinical, radiologic and experimental data that anatomic disturbances at the esophageal hiatus account for physiologic alterations. A reasonable explanation for the symptoms and signs of esophageal hiatal hernia can be made on the basis of the functional competence of the three-in-line sphincter mechanisms.

Abdominal Muscles↗
PubMed1991

Effects of pentobarbital on respiratory functional dynamics in chronically instrumented guinea pigs.

Respiratory effects of sodium pentobarbital (35 mg/kg; IP) were studied in guinea pigs chronically instrumented to permit concurrent recordings of bulbar respiratory-related units (RRUs), diaphragmatic electromyogram (DEMG), and electrocorticogram (ECoG). RRU activities were recorded from either the Bötzinger Complex (BOT; expiratory) or Nucleus para-Ambiguus (NpA; inspiratory). Pentobarbital-induced changes in respiratory-related activities were evaluated before, throughout the course of, and during recovery from, anesthesia. The most notable development following pentobarbital was a state of progressive bradypnea which was accompanied by a variety of complex changes in the amplitude and temporal attributes of RRU, DEMG and ECoG activities. As anesthetic effects progressed, the activity profiles of both BOT and NpA units underwent striking transformations from a behavioral and state-dependent wakefulness pattern to an activity profile characterized by i) a significantly augmented RRU cycle duration, burst duration and spike frequency; and, ii) an alteration to the pattern of within-burst spike frequency modulation. Along with changes in RRU activity, pentobarbital also produced a marked attenuation of the amplitudes of diaphragmatic activity as well as a discrete, time-dependent alteration in the amplitude and spectral characters of ECoG activities. Differences in BOT and NpA unit responses to alveolar CO2 loading (ramp; 2% and 5%) across wakefulness and anesthesia states were also considerable. In addition to a depressed responsiveness to CO2, the temporal attributes of BOT and NpA activity profiles also indicated an asymmetrical change under pentobarbital anesthesia. Taken together, these findings indicate that pentobarbital causes not only a fundamental alteration in bulbar rhythmogenic mechanisms, but also a differential influence on bulbar respiratory system components that are involved in the definition of the shape and the amplitude of central respiratory drive. In conclusion, this study offers, for the first time, direct evidence from physiologically and structurally intact preparations that the functional dynamics of respiratory system components are profoundly altered during pentobarbital anesthesia.

Animals↗
PubMed2002

Osteological and morphometric observations on intervertebral joints in the canine pre-diaphragmatic thoracic spine (Th1-Th9).

The incidence of facet aplasia was investigated in three groups of pure-bred dogs. We examined large breeds (Rough Collies, Doberman Pinschers, Rottweilers, Bernese Mountain Dogs, German Shepherd Dogs), chondrodystrophic breeds (Dachshunds, Pekinese dogs), and small breeds (Yorkshire Terriers, Maltese dogs). Uni- or bilateral aplasia of zygapophyseal (facet) joints was exclusively found in juvenile and adult small dogs, in which the incidence of aplasia ranged from between 26% (Th1) and 63% (Th8). There was no evidence that aplasia of zygapophyseal joints increases the risk of developing intervertebral disc disease or deformative spondylosis in small breeds. By applying the findings of previous empirical studies on intervertebral disc geometry and its biomechanical behaviour on the present morphometric results, there was an indication that the intervertebral disc may well compensate for the functional loss of aplastic zygapophyseal joints in small dogs. Biomechanical factors and their potential role as inducing agents of facet aplasia in the pre-diaphragmatic thoracic spine are also discussed.

Aging↗
PubMed1988

Timing of surgery for congenital diaphragmatic hernia: is emergency operation necessary?

Congenital diaphragmatic hernia (CDH) is considered by most researchers to be a surgical emergency. However, early repair does not necessarily improve respiratory function or reverse fetal circulation, and many patients deteriorate postoperatively. As a result, in 1985, we began to employ a protocol in which surgery was delayed until the PCO2 was maintained below 40 and the child was hemodynamically stable; children in whom these criteria could not be achieved died without surgical repair. Sixty-one consecutive infants with CDH were managed over 4 years; 31 from 1983 to 1984 (group 1) and 30 from 1985 to 1986 (group 2). The groups were similar with respect to sex, side of the defect, birth weight, gestational age, incidence of pneumothorax, and blood gases. High frequency oscillation was used with increasing frequency during the study period, for patients with refractory hypercarbia (13% in group 1, 30% in group 2). All patients were initially paralyzed and ventilated. Mean time from admission to surgery was 4.1 hours in group 1 and 24.4 hours in group 2 (P less than .05). In group 1, 87% of patients had surgical repair (77% within eight hours of admission, 10% after eight hours), and in group 2 only 70% of patients had surgery (10% within eight hours, 60% after eight hours). All patients who were not operated on died. Overall mortality was 58% in group 1 and 50% in group 2; this difference was not statistically significant. These data indicate that our current approach has not increased overall mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

Emergencies↗