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De Groote, A., M. Wantier, G. Cheron, M. Estenne, and M. Paiva. Chest wall motion during tidal breathing. J. Appl. Physiol. 83(5): 1531–1537, 1997.—We have used an automatic motion analyzer, the ELITE system, to study changes in chest wall configuration during resting breathing in five normal, seated subjects. Two television cameras were used to record the x-y-z displacements of 36 markers positioned circumferentially at the level of the third (S1) and fifth (S2) costal cartilage, corresponding to the lung-apposed rib cage; midway between the xyphoid process and the costal margin (S3), corresponding to the abdomen-apposed rib cage; and at the level of the umbilicus (S4). Recordings of different subsets of markers were made by submitting the subject to five successive rotations of 45–90°. Each recording lasted 30 s, and three-dimensional displacements of markers were analyzed with the Matlab software. At spontaneous end expiration, sections S1–3 were elliptical but S4 was more circular. Tidal changes in chest wall dimensions were consistent among subjects. For S1–2, changes during inspiration occurred primarily in the cranial and ventral directions and averaged 3–5 mm; displacements in the lateral direction were smaller (1–2 mm). On the other hand, changes at the level of S4 occurred almost exclusively in the ventral direction. In addition, both compartments showed a ventral displacement of their dorsal aspect that was not accounted for by flexion of the spine. We conclude that, in normal subjects breathing at rest in the seated posture, displacements of the rib cage during inspiration are in the cranial, lateral outward, and ventral directions but that expansion of the abdomen is confined to the ventral direction.

Although all the well-recognized muscles of expiration are paralyzed after traumatic transection of the lower cervical cord, tetraplegic subjects can still empty their lungs actively by contracting the clavicular portion of the pectoralis major. It is not known, however, whether contraction of this muscle bundle may raise pleural pressure enough to cause dynamic compression of the intrathoracic airways, which is critical for the production of an effective cough. To investigate this question, we measured expiratory flow rate and esophageal pressure during a series of forced expiratory vital capacity (VC) maneuvers in twelve subjects with C5-8 traumatic tetraplegia and constructed isovolume-pressure flow (IVPF) curves. The curves were interpretable with certainty in nine patients. Three of them did not show any plateau of flow. On the other hand, six patients had clearcut plateaus of flow on all IVPF curves between 80-60 and 20% VC, suggesting they had dynamic airway compression. Videoendoscopic recordings in two patients confirmed trachea and main bronchi collapse during forced expiration and cough. We conclude, therefore, that contraction of the pectoralis major causes dynamic airway compression during expiratory efforts in a substantial proportion of tetraplegic subjects. Increasing the pressure-generating capacity of this muscle might thus improve the effectiveness of cough and reduce the prevalence of bronchopulmonary infections.

BACKGROUND--It is well established that patients with longstanding weakness of the respiratory muscles have a reduction in lung distensibility. Although this occurs in most patients without any radiographic changes suggesting parenchymal lung disease, it has been attributed to the development of microatelectasis. METHODS--A high resolution computed tomographic (CT) scanner was used in eight patients with traumatic tetraplegia and six patients with generalised neuromuscular disorders to look for areas of atelectasis. With the patient in the supine posture scans of 1 mm thickness were obtained at total lung capacity at intervals of 1 cm from the apex to the base of the lung. RESULTS--Vital capacity, total lung capacity, and inspiratory muscle strength were reduced to a mean of 59.5%, 73.9%, and 51.1% of predicted values, respectively. Static expiratory lung compliance was decreased in 12 of the 14 patients and averaged 69.1% of the predicted value. The CT scans revealed only small areas of atelectasis in one tetraplegic patient and in one patient with a generalised neuromuscular disorder; no parenchymal abnormality was seen in the other 12 patients. CONCLUSIONS--In many patients with chronic weakness of the respiratory muscles the reduced lung distensibility does not appear to be caused by microatelectasis. It might be related to alterations in elasticity of the lung tissue.

In 2010, lung transplantation is a valuable therapeutic option for a number of patients suffering from of end-stage non-neoplastic pulmonary diseases. The patients frequently regain a very good quality of life, however, long-term survival is often hampered by the development of complications such as the bronchiolitis obliterans syndrome, metabolic and infectious complications. As the bronchiolitis obliterans syndrome is the first cause of death in the medium and long term, an intense immunosuppressive treatment is maintained for life in order to prevent or stabilize this complication. The immunosuppression on the other hand induces a number of potentially severe complications including metabolic complications, infections and malignancies. The most frequent metabolic complications are arterial hypertension, chronic renal insufficiency, diabetes, hyperlipidemia and osteoporosis. Bacterial, viral and fungal infections are the second cause of mortality. They are to be considered as medical emergencies and require urgent assessment and targeted therapy after microbiologic specimens have been obtained. They should not, under any circumstances, be treated empirically and it has also to be kept in mind that the lung transplant recipient may present several concomitant infections. The most frequent malignancies are skin cancers, the post-transplant lymphoproliferative disorders, Kaposi's sarcoma and some types of bronchogenic carcinomas, head/neck and digestive cancers. Lung transplantation is no longer an exceptional procedure; thus, the pulmonologist will be confronted with such patients and should be able to recognize the symptoms and signs of the principal non-surgical complications. The goal of this review is to give a general overview of the most frequently encountered complications. Their assessment and treatment, though, will most often require the input of other specialists and a multidisciplinary and transversal approach.

In 2009 lung transplantation is a valuable therapeutic option for a number of patients suffering from end-stage pulmonary diseases. Lung transplantation frequently offers a major improvement in quality of life; however, long-term survival is often limited by the development of the bronchiolitis obliterans syndrome, which is the equivalent of a chronic pulmonary graft rejection. As the bronchiolitis obliterans syndrome is the commonest cause of death in the medium- and long-terms, all patients receive intense immunosuppressive treatment in order to prevent or stabilize this complication. This treatment induces a number of potentially severe complications including metabolic complications, infections and malignancies. The most frequent metabolic complications are arterial hypertension, chronic renal insufficiency, hyperlipidaemia, diabetes and osteoporosis. Bacterial, viral and fungal infections are the second commonest cause of mortality. They are to be considered as medical emergencies and require urgent assessment and targeted therapy after microbiological specimens have been obtained. They should not under any circumstances be treated empirically and it should also be kept in mind that the lung transplant recipient may present several concomitant infections. The most frequent malignancies are post-transplant lymphoproliferative disorders, cutaneous neoplasias, Kaposi's sarcoma, some peculiar types of head and neck neoplasia, bronchogenic carcinomas and cancers of the digestive tract. The respiratory physician should recognize the symptoms and signs of specific complications induced by the immunosuppressive regimen and the goal of this report is to give a general overview of the most frequently encountered complications. Their assessment and treatment, though, will most often require the input of other specialists and a multidisciplinary approach.

In 2009 lung transplantation is a valuable therapeutic option for a spectrum of end-stage pulmonary diseases. To many patients who are dying, lung transplantation offers a new and normal life for several years. However, lung transplantation is a major surgical intervention associated with a significant early mortality. Moreover, matching according to the major human histocompatibilty antigens is impossible, exposing the recipient to an increased risk of acute and chronic rejection. Chronic rejection and its clinical corollary the bronchiolitis obliterans syndrome, is the main cause of death medium and long term. The immunosuppressive treatment administered in order to prevent or stabilize this complication induces a number of potentially severe complications including infection, malignancies, and cardio-vascular, metabolic and renal complications which not only limit autonomy and quality of life, but also cause death in a number of long term survivors. A better understanding of the precise mechanisms underlying the development of the bronchiolitis obliterans syndrome and the development of specific preventive or therapeutic strategies will be key elements for the improvement of long term survival. The control of this main cause of death will allow individual tailoring of the immunosuppressive therapy and decrease the incidence of infectious and metabolic complications.

We studied the effect of 15–20 s of weightlessness on lung, chest wall, and abdominal mechanics in five normal subjects inside an aircraft flying repeated parabolic trajectories. We measured flow at the mouth, thoracoabdominal and compartmental volume changes, and gastric pressure (Pga). In two subjects, esophageal pressures were measured as well, allowing for estimates of transdiaphragmatic pressure (Pdi). In all subjects functional residual capacity at 0 Gz decreased by 244 +/- 31 ml as a result of the inward displacement of the abdomen. End-expiratory Pga decreased from 6.8 +/- 0.8 cmH2O at 1 Gz to 2.5 +/- 0.3 cmH2O at Gz (P less than 0.005). Abdominal contribution to tidal volume increased from 0.33 +/- 0.05 to 0.51 +/- 0.04 at 0 Gz (P less than 0.001) but delta Pga showed no consistent change. Hence abdominal compliance increased from 43 +/- 9 to 70 +/- 10 ml/cmH2O (P less than 0.05). There was no consistent effect of Gz on tidal swings of Pdi, on pulmonary resistance and dynamic compliance, or on any of the timing parameters determining the temporal pattern of breathing. The results indicate that at 0 G respiratory mechanics are intermediate between those in the upright and supine postures at 1 G. In addition, analysis of end-expiratory pressures suggests that during weightlessness intra-abdominal pressure is zero, the diaphragm is passively tensed, and a residual small pleural pressure gradient may be present.

The department of pneumology of the Erasme hospital exists since 25 years. The basic clinical activities include pulmonary function testing (7,500 patients per year), endoscopy, including interventional endoscopy (1,500 patients per year), thoracic oncology, allergology, rehabilitation and aid to smoking cessation. The following expertise fields have been largely developed: lung transplantation, treatment of cystic fibrosis in collaboration with the children's hospital Reine Fabiola, occupational.

Lymphomatoid granulomatosis is an Epstein-Barr virus-associated B-cell lymphoproliferative disease. It is angiocentric and angiodestructive and involves the lungs, central nervous system and skin. Exclusive cutaneous involvement is rare and may be associated with a better outcome. Contrarily to the extra-cutaneous forms of lymphomatoid granulomatosis, it is difficult or impossible to detect Epstein-Barr virus DNA sequences in primary and isolated cutaneous lymphomatoid granulomatosis.A 54-year-old woman developed erythemato-violaceous lesions on both legs 3 years after a heart-lung transplantation. The diagnosis of erythema multiforme and of drug-induced vasculitis were first made. Because of fever and of the rapid extension of the lesions, the patient was hospitalized. The histologic examination of the first lesions showed a perivascular infiltrate, without epidermotropism, composed of histiocytes, lymphocytes and plasma cells. Immunohistochemistry revealed the presence of a predominantly T-cell infiltrate with some large B cells. Subsequent biopsies were diagnosed as high grade B-cell lymphoma. Polymerase chain reaction analysis as well as in situ hybridation study showed the presence of Epstein-Barr virus load in the lesions. There was however no serologic evidence of viral reactivation. Extensive systemic evaluation revealed no visceral or bone marrow involvement. Despite antiviral treatment and CHOP polychemotherapy, the patient died 3 months after her admission.This observation of lymphomatoid granulomatosis is particular because of its exclusive cutaneous involvement associated with a fulminant evolution to high grade B lymphoma. The presence of a context of iatrogenic immunosuppression underlies the role of altered immune cellular functions in the initiation and/or progression of lymphomatoid granulomatosis and strengthens the role of a viral agent in its pathogenesis. We suggest that the presence of Epstein-Barr virus, which is generally not associated with the isolated cutaneous forms of lymphomatoid granulomatosis, may have played a role in this fulminant evolution to high grade B lymphoma.

Besides increasing the work of ventilation, emphysema increases lung volume which in itself has a deleterious effect on the inspiratory muscles. We review here the effects of an acute change in lung volume on the configuration of the rib cage and muscle function. We also discuss the effects of the chronic distension associated with emphysema. The effects produced by changes in muscle length and configuration on the mechanical force and action of inspiratory muscles is detailed with particular focus on the diaphragm and its structural adaptations to experimental emphysema. We also analyze the activation pattern of inspiratory and expiratory muscles during the breathing process in patients with emphysema. Finally, we discuss the effects of single-lung transplantation and reduction surgery on chest distension and improved inspiratory muscle function.

Peripheral blood mononuclear cells (PBMC) of stable renal or cardiac transplant recipients were previously shown to respond to allogeneic cells but not to soluble protein antigens. The aim of the present study was to assess the T-cell and antigen-presenting cell (APC) functions of stable lung transplant (LT) recipients.We obtained PBMC from 38 stable LT recipients. PBMC from healthy volunteers served as controls. PBMC were stimulated with either anti-CD3 monoclonal antibody, allogeneic PBMC, or tetanus toxoid (TT). T-cell activation was assessed by determination of interleukin (IL)-2 levels in culture supernatants; in some experiments, interferon-y levels were also determined. Patients' APC function was tested in a mixed leukocyte reaction using patients' PBMC as stimulators. The expression of class II MHC, B7.2, and CD40 molecules on patients' APC was determined by flow cytometry, and their production of IL-10 and IL-12 at the basal state and upon CD40 ligation was also measured.Patients' T cells produced normal amounts of IL-2 in response to anti-CD3 monoclonal antibody and allogeneic PBMC. In contrast, the response of memory T cells to TT was severely blunted both in terms of IL-2 and interferon-y production. Patients' PBMC were poor stimulators in mixed leukocyte reaction, and class II MHC expression on patients' monocytes was significantly reduced. Patients' APC presented a modest but significant increase in basal IL-10 production and produced significantly less IL-12 upon CD40 ligation than control APC.T cells from stable LT recipients respond normally to stimuli that do not depend on autologous APC. The major impairment in the T-cell response to TT is caused by APC dysfunction, which involves decreased class II MHC expression and deficient IL-12 synthesis.

Objective: To examine the effects of end-inspiratory pause (EIP) of different durations on pulmonary mechanics and gas exchange during one-lung ventilation (OLV) for thoracic surgery. Design: A prospective clinical study. Setting: A university hospital. Participants: Eleven patients undergoing elective pulmonary resection with pulmonary hyperinflation on their preoperative pulmonary function studies. Interventions: Patients were anesthetized, paralyzed, and intubated with a double-lumen endotracheal tube. Their lungs were ventilated with a Siemens 900C ventilator (Siemens; Solna, Sweden), with constant inspiratory flow. Tidal volume, respiratory rate, and inspiratory time were kept constant during the study. Measurements and Results: During one-lung ventilation in the lateral decubitus position, three levels of EIP (0%, 10%, and 30%) were applied to the dependent lung in random order. After 15 minutes on the given ventilatory pattern, end-inspiratory and end-expiratory occlusions of at least 5 seconds were performed to obtain respiratory mechanics data. Arterial blood gas samples were drawn to assess gas exchange. Altering the duration of end-inspiratory pause from 0% to 30% resulted in a significant increase in intrinsic positive end-expiratory pressure (PEEPi) from 4.1 cm H2O to 7.0 cm H2O. Arterial oxygenation was significantly decreased from 109.7 to 80.5 mmHg and there was a significant negative correlation between the value of partial pressure of arterial oxygen (PaO2) and PEEPi by altering the duration of end-inspiratory pause. From the preoperative pulmonary function studies, the value of functional residual capacity (FRC) (% predicted) showed a significant negative correlation with the Pa02 changes. Partial pressure of arterial carbon dioxide (PaCO2) was not altered significantly by increasing the duration of end-inspiratory pause. Conclusion: During the period of OLV in the lateral position of patients with preexisting pulmonary hyperinflation, the magnitude of PEEPi increased and oxygenation decreased significantly, whereas the efficacy of ventilation was not changed by the addition of an end-inspiratory pause to the ventilatory pattern. Because arterial oxygenation is affected by the presence of pulmonary hyperinflation, the method of ventilation should take into account the magnitude of preoperative pulmonary hyperinflation.

It has been postulated that chimerism after transplantation might promote graft acceptance. In the present study, we prospectively assessed blood chimerism in 10 lung transplant recipients during the first posttransplant year and investigated whether chimerism was associated with an immunologically stable situation of the graft.The recipients' peripheral blood mononuclear cells were obtained before transplantation and at various time points during the first postoperative year. Donor cells were detected using nested polymerase chain reaction amplification of a donor-specific HLA-DRB1 allele. Clinical graft acceptance was determined by the number of rejection episodes.The incidence of blood chimerism was high during the first 3 postoperative months and then decreased over time. All patients experienced at least one acute rejection episode, and three patients developed chronic rejection.We, thus, conclude that rejection of the lung allograft may occur in the presence of blood chimerism.

Lung transplantation results in dramatic improvement in pulmonary function which allows the patients to resume a normal lifestyle. When the lung allograft is free of infection and rejection, lung volumes and gas exchange are within normal limits after heart-lung and double lung transplantation, both at rest and during exercise. After single lung transplantation, lung volumes remain below predicted values and some patients show mild oxygen desaturation with exercise. Infection, acute rejection, and chronic rejection (bronchiolitis obliterans) produce an obstructive ventilatory defect. In addition, there is a bronchial hyperreactivity to cholinergic stimulation; this hyperreactivity might be related to airway denervation and upregulation of muscarinic receptors or might be triggered by the bronchial inflammation induced by rejection. Control of breathing is normal at rest, during exercise, in response to CO2 rebreathing, and during sleep. This indicates that pulmonary afferents play a negligible role in the control of breathing in adult humans. Most transplanted patients show a significant reduction in maximum oxygen consumption and have an early anaerobiosis during exercise; this response may be accounted for, at least in part, by a persistent state of physical deconditioning, and by an inadequate adaptation of cardiac output in heart-lung transplant recipients.

Chronic obstructive pulmonary disease (COPD) imposes a major strain on the respiratory muscle pump, and it is conventionally thought that the inspiratory muscles of the neck adapt to this chronic overload by developing hypertrophy. Yet previous anthropometric studies have shown atrophy of the sternomastoid muscles. To solve this discrepancy, we have measured the cross-sectional area of these muscles by computed tomography. Ten stable patients with severe airflow obstruction (FEV1 = 0.76 +/- 0.12 L) and hyperinflation (FRC = 210 +/- 29% of predicted) and 10 control subjects matched for age, sex, and height were studied. The sternomastoid cross-sectional area in the patients averaged (mean +/- SD) 4.29 +/- 1.48 cm2, and that in the control subjects was 3.96 +/- 0.82 cm2. This small difference could be entirely accounted for by hyperinflation, and it was not statistically significant. Sternomastoid muscle torque in patients was also similar to that in the control subjects. In patients with severe COPD, therefore, the sternomastoid muscles are essentially normal. As a corollary, their frequent prominence on clinical examination is only apparent.

We studied the effect of microgravity (0 Gz) on the anteroposterior diameters of the upper (URC-AP) and lower (LRC-AP) rib cage, the transverse diameter of the lower rib cage (LRC-TR), and the xiphipubic distance and on the electromyographic (EMG) activity of the scalene and parasternal intercostal muscles in five normal subjects breathing quietly in the seated posture. Gastric pressure was also recorded in four subjects. At 0 Gz, end-expiratory LRC-AP and xiphipubic distance increased but LRC-TR invariably decreased, as did end-expiratory gastric pressure. No consistent effect was observed on tidal LRC-TR and xiphipubic displacements, but tidal changes in URC-AP and LRC-AP were reduced. Although scalene and parasternal phasic inspiratory EMG activity tended to decrease at 0 Gz, both muscle groups demonstrated an increase in tonic activity. We conclude that during brief periods of weightlessness 1) the rib cage at end expiration is displaced in the cranial direction and adopts a more circular shape, 2) the tidal expansion of the ventral rib cage is reduced, particularly in its upper portion, and 3) the scalenes and parasternal intercostals generally show a decrease in phasic inspiratory EMG activity and an increase in tonic activity.

We used a high-resolution ultrasound to make electrical recordings from the transversus abdominis muscle in humans. The behavior of this muscle was then compared with that of the external oblique and rectus abdominis in six normal subjects in the seated posture. During voluntary efforts such as expiration from functional residual capacity, speaking, expulsive maneuvers, and isovolume “belly-in” maneuvers, the transversus in general contracted together with the external oblique and the rectus abdominis. In contrast, during hyperoxic hypercapnia, all subjects had phasic expiratory activity in the transversus at ventilations between 10 and 18 l/min, well before activity could be recorded from either the external oblique or the rectus abdominis. Similarly, inspiratory elastic loading evoked transversus expiratory activity in all subjects but external oblique activity in only one subject and rectus abdominis activity in only two subjects. We thus conclude that in humans 1) the transversus abdominis is recruited preferentially to the superficial muscle layer of the abdominal wall during breathing and 2) the threshold for abdominal muscle recruitment during expiration is substantially lower than conventionally thought.

The influence of age and posture on compliance of the rib cage (Crc) and diaphragm-abdomen (Cab) compartments of the chest wall was studied in 61 healthy adults (33 men, 28 women) aged 24-75 yr. Chest wall compliance (Cw) was measured by the weighted spirometer technique; Crc and Cab were derived from the slope of the relaxation line of the thoracoabdominal system obtained with two pairs of linearized magnetometers. While Cw was being measured, we monitored electrical activity of the abdominal external oblique muscle with a concentric needle electrode and thoracoabdominal configuration. In 52 subjects, the electromyogram did not show any abdominal muscle activity and the end-expiratory level never departed from the relaxed thoracoabdominal configuration, thus suggesting adequate respiratory muscle relaxation. Aging was associated with significant decreases in Crc and Cab. In the upright posture Crc decreased from 0.164 +/- 0.041 (mean +/- SD) l/cmH2O in the younger subjects (24-39 yr) to 0.114 +/- 0.027 l/cmH2O in the older subjects (55-75 yr). Cab concomitantly fell from 0.032 +/- 0.012 l/cmH2O to 0.020 +/- 0.007 l/cmH2O. These reductions were statistically significant (P less than 0.05-0.01) and were also present in the supine posture. Shifting from the seated to the supine posture did not cause any significant change in Cw but was invariably associated with a decrease in Crc and an increase in Cab.(ABSTRACT TRUNCATED AT 250 WORDS)

A reduced total lung capacity associated with a normal or decreased lung recoil pressure at full inflation (Pel max) has been noted in patients with valvular heart lesions. In order to investigate the mechanism underlying this inappropriately low Pel max, we measured respiratory mechanics in a group of 15 patients with mitral valve disease uncomplicated by other illness. The total lung capacity was 81 percent of control. The static pressure-volume curve of the long intersected the normal one in the vicinity of functional residual capacity (i.e., the recoil pressure was increased at large lung volumes and diminished at low lung volumes), and both expiratory compliance and Pel max were significantly decreased. In 13 of the 15 patients, the minimal (inspiratory) pleural pressure-volume curve was shifted so that the pressures generated by the inspiratory muscles were less negative than normal at any given lung volume. The decrease in Pel max was proportional to the alteration in muscle pressures. These findings indicate (1) that patients with mitral valve disease have compromised function of the inspiratory muscles, and (2) that this alteration is responsible for the low Pel max. Respiratory muscle weakness contributes to the restriction of lung volume in patients with pulmonary vascular congestion and is probably implicated in cardiac dyspnea.

We studied respiratory mechanics and phrenic nerve and diaphragm function in 12 patients on the day before and eight to 13 days after coronary artery bypass grafting. The average vital capacity, functional residual capacity, and total lung capacity decreased by 20.5%, 9.5%, and 14.7% respectively after operation. Eleven patients showed less negative maximum inspiratory mouth pressures at any given lung volume after surgery and the magnitude of the change correlated with the reduction in total lung capacity. In 11 of the 12 patients the conduction times of the right and left phrenic nerves did not change substantially after operation and the ratio of inspiratory electrical activity (Edi) of left and right hemidiaphragms was similar before and after the procedure. One patient, however, showed a considerable increase in left phrenic nerve conduction time and a reduction in the left to right Edi ratio postoperatively. In three patients diaphragm function was also assessed by changes in transdiaphragmatic pressure during supramaximal phrenic nerve stimulation and voluntary increase in inspired volume; in none of the three patients did the transdiaphragmatic pressure swings show any significant change in the postoperative period. These data indicate that phrenic nerve paralysis only occasionally accounts for the postoperative loss of lung volume after coronary artery bypass grafting surgery. The mechanism of these abnormalities therefore remains to be determined.

Interstitial lung disease developed in a 32-yr-old chemist after working 8 yr in a dusty atmosphere containing aluminum powders. Bronchoalveolar lavage disclosed a helper T-lymphocyte alveolitis, and transbronchial lung biopsies showed sarcoidlike epithelioid granulomas. These granulomas contained dust identified by mineralogic analyses as consisting mainly of aluminum particles. Nasal and liver biopsies and a Kveim test did not reveal extrapulmonary granulomatous infiltration. An extensive immunologic work-up showed none of the abnormalities classically seen in sarcoidosis, but peripheral blood lymphocytes exhibited blastic transformation in the presence of soluble aluminum compounds. About 1 yr after cessation of exposure, a chest radiograph and lung function tests remained essentially unchanged, but signs of alveolitis disappeared. This observation suggests that aluminum may cause granulomatous lung disease accompanied by a helper T-lymphocyte alveolitis, similar to that of berylliosis and sarcoidosis. Further observations would be necessary to show if this constitutes an early stage of aluminum-induced fibrosis (aluminum lung).

To determine the action of the parasternal intercostals on the human rib cage, we studied the pattern of rib cage motion in relation to the pattern of respiratory muscle contraction in 4 normal subjects during attempts to perform tidal volume breathing with the parasternal intercostals alone. The dimensions of the chest wall, including the anteroposterior (AP) diameters of the lower rib cage and the abdomen, the transverse diameter of the lower rib cage, and the xiphipubic distance, were measured with linearized magnetometers. The electromyogram (EMG) of the diaphragm was obtained with an esophageal lead, while the EMGs of the intercostal, neck, and abdominal muscles were recorded using concentric needle electrodes. Minimizing diaphragmatic use during inspiration (transdiaphragmatic pressure = 0.08 to 1.54 cm H2O) was accompanied by a recruitment of the parasternals that was substantially greater than that of the scalenes; in 2 of the subjects, the activation of the scalenes at the beginning of inspiration was even delayed relative to the parasternals. The lateral intercostals showed variable changes during the maneuver, but the sternocleidomastoids, pectoralis major, rectus abdominis, and abdominal external oblique muscles were always silent. This pattern of EMG activity was associated with profound deformations of the rib cage. In all 4 subjects, the rib cage expanded considerably more along its transverse than its AP dimension relative to its relaxed configuration, and in 3 subjects, the xiphi-pubic distance decreased rather than increased in early inspiration.(ABSTRACT TRUNCATED AT 250 WORDS)

Eighteen sequential follow-up measurements of pulmonary function were obtained over a period of 21 months after heart-lung transplantation in a patient who had undergone surgery for end-stage pulmonary lymphangioleiomyomatosis. In the early postoperative period, there was a moderate decrease in VC and TLC but gas exchange was maintained at essentially normal levels. The most conspicuous features of postoperative lung function were a very low airway resistance and an increase in FEV1/VC ratio above 95%. These alterations were associated with an unusual shape of the maximal expiratory flow-volume (MEFV) curve. Instead of showing a uniform decrease in expiratory flow as expiration proceeds to residual volume, the post-transplant MEFV curve showed a peak followed by a gently sloping plateau ending at a knee where flow suddenly fell. The knee occurred after exhalation of 80% VC. From the sixth postoperative month, the patient developed rapidly increasing air-flow obstruction, which proved to be due to obliterative bronchiolitis. As air-flow obstruction worsened, the knee on the MEFV curve progressively occurred at a higher lung volume, the flow plateau shortened, and flow after the knee became smaller at a given volume. From the ninth postoperative month, it was no longer possible to identify a plateau-knee configuration on the MEFV curve, which resembled that seen in severe obstructive airway disease.(ABSTRACT TRUNCATED AT 250 WORDS)

The variability of quasistatic lung inspiratory and expiratory pressure-volume (P-V) curves has been investigated in 8 young healthy volunteers studied on 4 occasions. The reproducibility of the total lung capacity (TLC) measured by body plethysmography was good, with a mean coefficient of variation of 1.8 +/- 0.9% (SD). The following variables were calculated from the P-V curves: the recoil pressures measured at TLC and 90, 80, 70, 60, and 50% TLC, as well as the compliance at functional residual capacity. For all the variables considered the intraseries variance was similar to the interseries variance so that all the individual results were pooled together. For each variable a coefficient of variation was calculated for each subject, as well as an F ratio to compare the interindividual differences to the intraindividual differences. For the variables obtained from the expiratory P-V curve, the lowest coefficient of variation was found for elastic lung recoil pressure, 90% TLC (6.6 +/- 2.6%, mean +/- SD). The reproducibility of the inspiratory P-V curve was found to be somewhat better than that of the expiratory one, with a coefficient of variation of 3.4 +/- 0.8% at 90% TLC. In absolute terms at that same level, the mean standard error of measurements was 1.2 cm H2O for the expiratory curves and 0.8 cm H2O for the inspiratory ones. It is concluded that in terms of reproducibility the best index of lung elasticity is the recoil pressure measured at 90% TLC and that the inspiratory curve is even better than the expiratory one.

To assess the actions of the rectus abdominis and external oblique muscles on the rib cage in humans, these two muscles were stimulated with surface electrodes in four normal supine subjects at functional residual capacity. Changes in anteroposterior and transverse rib cage diameters and changes in xiphipubic distance were measured with pairs of magnetometers. Stimulation of rectus abdominis produced a marked decrease in the xiphipubic distance and in the anteroposterior diameter, thus making the rib cage more elliptic. In contrast, stimulation of the external oblique caused a decrease in the transverse diameter, making the rib cage more cylindrical. When both muscles were stimulated simultaneously, the resultant rib cage distortion depended on the relative voltage at which each muscle was stimulated. Electromyogram recordings showed that there was no cross contamination or activity of the diaphragm during the muscle stimulations. Transdiaphragmatic pressure increased with the voltage of stimulation, suggesting passive lengthening of the diaphragm. X-ray studies were performed in two subjects and confirmed the main magnetometer findings. These studies thus confirm that the rib cage in humans is more easily distortable than conventionally thought. The abdominal muscles can distort it in either direction depending on which muscles are contracting.

A patient with myotonia congenita (Thomsen's disease) presented with unpleasant sensations of tightness in the chest and dyspnea, which were maximal at the beginning of exercise and gradually improved as exercise progressed. Lung function tests and maximal static respiratory pressures were within normal limits. Precise electromyographic (EMG) and mechanical studies, however, demonstrated the increased excitability, impaired relaxation, and transient weakness of the respiratory muscles. These studies thus indicate that myotonia congenita may involve the respiratory muscles to the same extent as any other skeletal muscle, and that precise EMG studies are occasionally useful in determining the organic basis of respiratory symptoms.

The pattern of activation of the scalenes and the parasternal intercostal muscles was studied in relation to the pattern of rib cage and abdominal motion during various respiratory maneuvers in the tidal volume range in five normal humans. Electromyograms (EMG) of the scalenes and parasternal intercostals were recorded with bipolar needle electrodes, and changes in abdominal and rib cage displacement were measured using linearized magnetometers. The scalenes and parasternal intercostals were always active during quiet breathing, and their pattern of activation was identical; in both muscles the EMG activity usually started together with the beginning of inspiration, increased in intensity as inspiration proceeded, and persisted into the early part of expiration. In addition, like the parasternal activity the scalene inspiratory activity persisted until the tidal volume was trivial, increased during tidal inspirations performed with the rib cage alone, and was nearly abolished during diaphragmatic isovolume maneuvers. However, attempts to perform tidal inspiration with the diaphragm alone, while causing an increase in parasternal EMG activity, were associated with a marked reduction or a suppression of scalene EMG activity and a reduced substantially distorted rib cage expansion. In particular, the upper rib cage was then moving paradoxically.(ABSTRACT TRUNCATED AT 250 WORDS)

We studied the effects of an intravenous injection of 5.0 mg of aminophylline per kg of body weight on lung mechanics in 8 normal subjects. No change occurred in lung volumes, airway resistance, and maximal expiratory flow-volume and lung pressure-volume curves. Restudy of 4 of the subjects before and after an injection of 8.0 mg/kg of aminophylline did not modify the pattern of response to the drug, despite a serum concentration range of 15.1 to 19.3 mg/l. These findings were, therefore, in contrast with those observed after the administration of atropine or beta-2 adrenergic derivatives. They suggested that the bronchodilator effects of aminophylline may not be due to a direct action of the drug on the bronchial smooth muscle.

It is well established that unlike normal subjects patients with cervical cord transection have an increase in VC when changing from the seated to the supine posture. To investigate the mechanism of this paradoxical increase, we measured static lung volumes in both the seated and supine posture in 14 consecutive patients with tetraplegia (C4-C7) and in 4 patients with paraplegia (Th4-Th7). The increase in VC in the supine compared with the seated posture was (mean +/- SE) 0.41 +/- 0.07 L (16.0% of the seated value) in the tetraplegic subjects and 0.40 +/- 0.01 L (11.2% of the seated value) in the paraplegic subjects (p less than 0.001). However, TLC in all subjects was 0.28 +/- 0.05 L smaller in the supine posture (p less than 0.001), thus indicating that the larger VC in this posture is related to a reduction in residual volume (RV) rather than to an increased mechanical advantage of the diaphragm. The reduction in RV in the supine posture was consistent, averaging 0.72 +/- 0.06 L (29.1% of the seated value) in the tetraplegic subjects and 0.62 +/- 0.21 L (37.6 percent of the seated value) in the paraplegic subjects (p less than 0.001). Inflating blood pressure cuffs at the bases of the legs prior to the assumption of the supine posture diminished the reduction in RV with recumbency by only 0.10 +/- 0.02 L. In contrast, the postural dependence of RV was abolished when the abdomen was tightly supported by elastic straps and maintained constant in configuration during postural changes.(ABSTRACT TRUNCATED AT 250 WORDS)

During a five year period 36 episodes of septicaemia in 32 patients with hepatic cirrhosis were documented. This represents 20% of the patients hospitalized with a decompensated cirrhosis and 1.1% of the patients with non decompensated cirrhosis. In patients with decompensated cirrhosis, enteric Gram-negative organisms were most frequently isolated (91% of the cases) and ascitis was infected in one third of the cases. No primary foci of infection were documented. On the contrary patients with a non decompensated cirrhosis had infection mostly with Gram-positive organisms (82%) and foci of infection (skin, throat) were documented in 38% of the cases. Infection by enteric organisms was associated with higher mortality than infection by non enteric organisms (68% vs 28%). Five patients with inappropriate antibiotic treatment died from septic shock. Spontaneous septicaemia and peritonitis are frequent complications if cirrhosis. There are potentially treatable causes of deterioration in the cirrhotic patient, necessitating prompt recognition and treatment.

Using the weighted spirometer technique we studied chest wall compliance (Cw) in 16 nonobese patients with chronic weakness of the respiratory muscles and 20 healthy control subjects. In order to evaluate the validity of the technique, while Cw was being measured, we monitored thoracoabdominal configuration with 2 pairs of linearized magnetometers and electrical activity of the external oblique with a concentric needle electrode in 3 healthy subjects and 4 patients; in addition, we recorded in 3 subjects the electrical activity from the intercostal muscles and diaphragm throughout the procedure. The method was reproducible within 5.8% and provided Cw values that compared well with those yielded by the relaxation technique. In each subject, the weight-induced shifts in end-expiratory lung volume showed a very good linear correlation with the changes in transrespiratory pressure at end-expiration (r greater than or equal to 0.91). In addition, in none of the subjects tested did the electromyograms reveal any intercostal, diaphragmatic, or abdominal muscle activity at end-expiration, nor did the end-expiratory level ever show a significant departure from the relaxed thoracoabdominal configuration, thus suggesting adequate respiratory muscle relaxation. The reduction in inspiratory muscle force in the patients ranged from 17 to 94% of predicted (mean +/- SE, 43 +/- 6). The decrease in vital capacity, total lung capacity, and functional residual capacity averaged 59, 34, and 15% of predicted, respectively. Both the patient and the control groups showed a large interindividual variability regarding Cw. It varied from 0.117 to 0.258 L/cm H2O (mean +/- SE, 0.162 +/- 0.012) in the patients and from 0.163 to 0.366 L/cm H2O (mean +/- SE, 0.248 +/- 0.013) in the healthy subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

The static elastic properties of the chest wall have been studied in 20 seated patients in the late stages of traumatic tetraplegia. Chest wall compliance (Cw) was measured using the weighted spirometer technique, and the slope of the relaxation line of the thoracoabdominal system obtained with 2 pairs of linearized magnetometers was used to derive rib cage (Crc) and diaphragm-abdomen (Cab) compliance. The values were compared with those obtained in 61 healthy adults studied with the same procedure. Chest wall compliance and Crc values in the patients were reduced to 72 and 55% of control values (p less than 0.001), respectively, and 9 of 20 patients had Crc values at least 2 SEE below normal. By contrast, Cab values in all patients were increased to 170% of control values (p less than 0.001), and 7 patients had values more than 2 SEE above normal. These alterations were not related to the duration of the disease or to the presence or absence of spastic activity in the parasternal intercostals. Both the decreased rib cage compliance and increased abdominal compliance may contribute to reducing rib cage contribution to tidal volume in tetraplegic subjects. As a corollary, the pattern of rib cage motion in such subjects can only approximately define the isolated action of the diaphragm on the normal human rib cage.

Quasistatic lung inspiratory and expiratory pressure-volume curves were obtained in 58 healthy nonsmoking males (mean age +/- SD: 42.8 +/- 15.1 years; range 22.70) and 56 healthy nonsmoking females (mean age +/- SD: 41.4 +/- 15.6 years; range: 21-76). Inspiratory and expiratory lung recoil pressures were measured at fixed percentages of TLC (100, 95, 90, 80, 70, 60 and 50%). In both sexes, inspiratory as well as expiratory lung recoil pressures were found to decrease linearly with aging (p less than 0.01 for all r values). There was no significant difference between males and females. At and above the 70% TLC level, the slopes of the age-related decreases in lung recoil were similar for the inspiratory and expiratory curves. At the 60% TLC level, the decrease in expiratory lung recoil was significantly (p less than 0.01) faster than the decrease in inspiratory lung recoil, presumably reflecting the influence of airway opening on the inspiratory pressure in older subjects. The shape of the expiratory PV curve described by the K index of the exponential model was similar in both sexes and changed with aging, K increasing significantly (p less than 0.01). By contrast, the shape of the inspiratory limb of the PV curve did not vary with aging. Consequently, the shape of the inspiratory PV curve cannot be predicted from the expiratory one and has to be measured directly.

The electromyograms of the triangularis sterni (transversus thoracis), of the abdominal external oblique, and of the deeper abdominal muscle layer (internal oblique or transversus abdominis) were recorded with concentric needle electrodes in twenty normal naive subjects breathing quietly in the supine and the standing posture. The triangularis sterni and abdominal muscles were usually silent in the supine posture. In contrast, all subjects in the standing posture showed activity in the abdominal muscles, and sixteen subjects also had activity in the triangularis sterni. The abdominal muscle activity was principally tonic, unrelated to the phase of the breathing cycle, whereas in fifteen subjects the triangularis sterni activity wa confirmed to expiration. Expiratory activation of the triangularis sterni was more frequently observed in the older than in the younger subjects of the study. These observations indicate that unlike in the supine posture, most normal subjects when breathing at rest in the standing posture recruit both the triangularis sterni and the abdominal muscles. This recruitment may compensate for the adverse effects of the standing posture on the diaphragm and rib cage inspiratory muscles.

In an attempt to understand the intersubject variation in rib cage motion in tetraplegia, and to assess the isolated action of the diaphragm on the human rib cage, we studied the pattern of rib cage motion in relation to the pattern of nondiaphragmatic respiratory muscle electromyogram (EMG) in 20 tetraplegic patients breathing at rest in the seated posture. The general pattern included a greater expansion of the lower than of the upper rib cage, and a greater and earlier expansion of the lower rib cage in its transverse than in its anteroposterior (AP) diameter. However, whereas the upper rib cage moved paradoxically inward with inspiration in 11 patients, it did not move or slightly expanded in 9 patients; in 1 of these, all rib cage diameters increased in the same proportion during inspiration as during relaxation. This intersubject variation was not related to the duration of tetraplegia, the pattern of the abdominal muscle EMG, or the presence of continuous spastic EMG activity in the parasternal intercostals. By contrast, it was related in part to the pattern of scalene EMG activity: upper rib cage AP paradox was present in 7 of 8 patients with spastic or silent scalenes but only in 4 of 12 patients with phasic inspiratory scalene EMG activity. When studied during quiet breathing in the supine posture, the 8 subjects with denervated scalene, intercostal, and abdominal muscles still showed inspiratory increase in the rib cage transverse diameter, but in 7 patients the lower rib cage AP diameter decreased in concert with the upper rib cage AP diameter.(ABSTRACT TRUNCATED AT 250 WORDS)

In an attempt to assess the action of the sternocleidomastoid muscles on the human rib cage, we studied the pattern of rib cage motion in 2 patients with complete transection of the upper cervical cord. Measurements of rib cage motion were obtained with magnetometers and chest roentgenograms, and concentric needle electrodes were used to record the electromyograms (EMG) of various respiratory muscles. Spontaneous quiet breathing elicited a large amount of phasic inspiratory EMG activity not only in the sternocleidomastoids, but also in the trapezii, platysma, mylohyoid, and sternohyoid muscles. This pattern of muscle use was associated with substantial rib cage deformation. During spontaneous inspiration both patients showed a clear-cut decrease in lower rib cage transverse diameter, and they both had a cranial displacement of the sternum and an increase in upper rib cage anteroposterior diameter that was disproportionately larger than the increase in lower rib cage anteroposterior diameter. Radiographic measurements confirmed these deformations but also demonstrated that the upper rib cage transverse diameter increased rather than decreased with inspiration. These results indicate that: (1) Patients with high tetraplegia use many neck muscles in addition to the sternocleidomastoids to breathe; (2) The synchronous contraction of these muscles acts to pull the sternum cranially, expands the upper rib cage, and causes paradoxical inward displacement of the lateral walls of the lower rib cage; (3) As in dogs, the motion of the upper rib cage in humans is more tightly linked to the sternum than that of the lower rib cage.(ABSTRACT TRUNCATED AT 250 WORDS)