Theodor Wanke

Increased sensitization to aeroallergens in competitive swimmers

Chlorine is used to disinfect swimming pools or as a constituent of other disinfection reagents. Pulmonary diseases are occasionally observed after exposure to chlorine. In 14 competitive swimmers and in 14 matched control subjects, we searched for clinically manifest allergies, subclinical sensitization to aeroallergens, imbalance of the cellular immune system, and bronchial hyperresponsiveness. Conjunctival or respiratory symptoms were found in 11 swimmers (2 cases of conjunctivitis, 4 rhinitis, 2 rhinoconjunctivitis, 1 laryngitis, and 2 bronchitis) and in 3 controls. Sensitization to aeroallergens was confirmed in 9 swimmers by skin test and in 11 swimmers by radioallergosorbent test (RAST), compared to findings in 4 and 5 controls, respectively. An altered cellular immune system, (i.e., imbalance in T-cell system, B-cell system, or natural killer cells) was detected in 7 swimmers and only 2 controls. Bronchial hyperresponsiveness to methacholine was seen in 11 swimmers and 5 controls. This higher incidence of allergic diseases and subclinical sensitization to aeroallergens, disorders of the cellular immune system, and bronchial hyperresponsiveness in competitive swimmers compared with control subjects could be due to repeated exposure to chlorine in swimming pools.

Allergenic structures in cockroach hypersensitivity

The tissues from which cockroach allergens were derived were identified by use of serum IgE of five patients with allergic rhinitis and bronchial asthma as a result of hypersensitivity to German cockroach. RAST and skin test results demonstrated four of five patients to be positive to cockroach only, and one patient was tested positive to house dust mite as well. Allergen-specific IgE binding to German cockroach was investigated by cryostat sections by means of immunofluorescent test. In all patients with cockroach hypersensitivity, we found IgE bound to the gastrointestinal epithelium and contents of the intestinal tract. In four cases, IgE was also bound to the Malpighian vessels (equivalent in function to kidneys). In three cases, IgE was also bound to the ovarian cells. All cases revealed cytoplasmic staining.

Phrenic nerve function in type 1 diabetic patients with diaphragm weakness and peripheral neuropathy.

Phrenic nerve latency was studied in 14 male type 1 diabetic patients with impaired diaphragm function and in 14 healthy control subjects. The diabetics showed significantly decreased values regarding inspiratory vital capacity and forced volume in 1 s compared with the control subjects. All other lung function parameters were similar in both groups. Although motor and sensory nerve conduction studies provided evidence for peripheral neuropathy in all patients, phrenic nerve latencies turned out to be normal. These results rule out a neuropathic disorder of the phrenic nerve. Thus, impaired diaphragm function in type 1 diabetic patients is not caused by phrenic neuropathy.

No Effect of Naloxone on Ventilatory Response to Progressive Hypercapnia in IDDM Patients

The ventilatory response to hyperoxic progressive hypercapnia was examined by comparing 3 test groups: 7 diabetic patients with AN, 8 diabetic patients without AN, and 8 normal control subjects. In each group, a significant linear correlation was found between PaCO2 and VE. The slopes of the regression curves relating PaCO2 to VE were significantly steeper in the healthy control subjects and diabetic patients without AN than in those with AN (P < 0.01). We conclude that the ventilatory response to progressive hypercapnia is reduced in diabetic patients with AN. By analyzing the power spectrum and the amplitude behavior of the diaphragmatic EMG (calculated from the fc and RMS, respectively), we could exclude a disturbance of neural descending pathways and respiratory muscle dysfunction as possible causal mechanisms for the impaired ventilatory response to increasing CO2. By using lung function analysis, causal factors such as alterations in respiratory system mechanics also could be excluded. As diabetes is known to affect the endogenous opioid system, which, in turn, affects the ventilatory response to CO2, naloxone, as a specific opioid antagonist, was administered in all 3 test groups. Naloxone produced a significant increase of ventilatory response to hypercapnia in the healthy control subjects (P < 0.01), but produced no effect in either of the diabetic groups. We conclude that the ventilatory response to hypercapnia is impaired in diabetic patients with AN, that lung function alterations and diaphragmatic muscle dysfunction are not responsible for this impairment, and that endogenous opioids produce an effect on the response to CO2 in healthy subjects, but they have no effect on CO2 response in diabetic patients with or without AN. These results suggest that the central control of respiration is pathologically altered in diabetic patients with AN.

Spontaneous bilateral diaphragmatic paralysis: a rare cause of respiratory failure.

SummaryBilateral diaphragmatic paralysis (BDP) can occur in the course of motor neuron disease, myopathy, or from mechanical damage or the use of “ice slush” during cardiac surgery. BDP has been observed during and after infections, associated with systemic lupus erythematosus and mediastinal tumors, or may have idiopathic etiology. It is a serious and life-threatening condition.A 62-yr-old man presented with slowly progressive dyspnoea that worsened in the supine position and on bending forward.Chest X-rays, fluoroscopy, lung-function parameters and blood-gas analysis revealed respiratory failure. BDP was confirmed from a phrenic nerve stimulation test and measurement of transdiaphragmatic pressure (Pdi). Since there was no evidence of an obvious etiology, BDP was considered idiopathic. Other muscles were not involved. The pathological basis was probably focal demyelination in segments of the phrenic nerve.Because of increasing diaphragmatic muscle fatigue, the patient was treated with a nasal mask providing bi-level positive airway pressure (BiPAP) ventilation during the night.Clinical suspicion of BDP should always be raised in patients suffering slowly progressive dyspnoea without any obvious cardiac, metabolic or traumatic predisposing factors, and orthopnoea and dyspnoea on bending forward. Electromyographic tests and measurement of Pdi can reveal the correct diagnosis.

Inspiratory muscle performance relative to the ventilatory threshold in healthy subjects.

Inspiratory muscle performance, ventilation, and gas exchange were studied during exercise in healthy subjects to look for typical changes of pattern of contraction at the ventilatory threshold (VT). The steepening of the slope of carbon dioxide output (VCO2) vs oxygen uptake (VO2) at the VT was accompanied by a nonlinear increase of the mean rate of esophageal pressure development (Pes/TI) vs the esophageal pressure time index (PTIes) reflecting both the relative force (Pbreath/Pesmax) and duration (TI/TTOT) required for inspiration. The esophageal pressure time integral within one breath (Pbreath.dTI) was one of the best single predictors of the ventilatory equivalent for oxygen (VE/VO2) at the VT. Moreover, we presented inspiratory muscle load indices as a mirror image of breathing pattern, with the obvious advantage that the ventilation component can be compared with better established methods of presenting ventilatory output. Inspiratory muscle performance during exercise should link the increased metabolic rate to ventilatory output. We conclude that 1) there exists an inspiratory muscle threshold that is well correlated to commonly used gas exchange thresholds, and 2) the efficiency of ventilation and gas exchange during exercise could be linked to pressure and timing of inspiratory muscle contraction.

Feedback-Controlled Negative Pressure Ventilation in Patients with Stable Severe Hypercapnic Chronic Obstructive Pulmonary Disease

Background: In recent studies, the efficacy of intermittent rest of the inspiratory muscles as an option of treating patients with severe chronic obstructive pulmonary disease (COPD) has become questionable. Objective: The aim of our study was to analyze the effects of feedback-controlled intermittent negative pressure ventilation (INPV) on stable, but severely hypercapnic COPD patients. Methods: 21 clinically stable, hypercapnic patients with severe COPD underwent INPV with chest shells for 3 weeks, 6 h a day. The INPV sessions were optimized by a visual biofeedback system, which enabled control over the decrease in diaphragmatic activity. Respiratory muscle (RM) function parameters, lung function parameters, blood gases and exercise capacity were analyzed. Results: In the end, 19 patients concluded INPV treatment. They had PaO2 of 56.5 ± 11.8 mm Hg, PaCO2 of 50.2±2.7 mm Hg (mean ± SD) and FEV1 of 27.8 ± 4.3% predicted before treatment. There was no statistically significant change in lung function parameters, RM function parameters, physical performance and level of dyspnea after 3 weeks of INPV. Conclusion: We conclude that intermittent RM rest induced by INPV can relax inspiratory muscles in most patients with stable severe COPD, but fails to improve RM function and exercise capacity.

Influences of the Cellular and Humoral Immune System in Bronchoalveolar Lavage on Lung Function in Pulmonary Sarcoidosis

We investigated the changes in the cellular and humoral immune system in bronchoalveolar lavage (BAL) performed in 22 patients with pulmonary sarcoidosis and in 14 normal control subjects and their interactions with lung function parameters. Lymphocytosis, the increase in OKT4+ lymphocytes and OKT4+OKDR+ lymphocytes correlated with the increase in immunoglobulins, especially IgG, IgA and kappa chain assembled immunoglobulins. The transferrin levels obtained in BAL were found to be higher in patients with sarcoidosis, and they correlated with the cellular and, more closely, with other humoral findings. A negative correlation existed between the ventilatory parameters and the cell count and humoral findings. In addition, we found a negative correlation between the diffusing capacity for carbon monoxide and other cellular findings, which was most pronounced with reference to lymphocytes, OKT4+ lymphocytes and the OKT4+/OKT8+ ratio. These results underscore the role of OKT4+ lymphocytes, activated OKT4+OKDR+ lymphocytes and transferrin in the increase in immunoglobulins, mainly kappa chain isotypes. Because of the relationship between these changes and ventilatory parameters, and the diffusing capacity, the above results also reveal the clinical relevance of our findings.

Diaphragmatic function in patients on continuous ambulatory peritoneal dialysis

We investigated 8 patients undergoing continuous ambulatory peritoneal dialysis (CAPD) for diaphragmatic strength and the neuromechanical efficiency of the diaphragm while the abdomen was filled with dialysate and while it was empty. Maximum transdiaphragmatic pressure (Pdimax) served as parameter for diaphragmatic strength; diaphragmatic efficiency was assessed by simultaneously monitoring transdiaphragmatic pressure (Pdi) and diaphragmatic electromyogram (EMGdi) during room-air breathing and hyperoxic CO2-rebreathing. After instilling dialysate, Pdimax increased from 76.7 ± 12.1 cmH2O to 92.2 ± 16.3 cmH2O (P < 0.05). While the slopes of the regression lines relating minute ventilation (VE) to arterial CO2 tension, and the change in VE for a given change in Pdi during hypercapnic rebreathing were similar in both states, the slope of EMGdi vs Pdi was significantly steeper when the abdomen was filled (P < 0.05). The increase in Pdimax observed in the filled state may suggest an adaptive rightward shift in the diaphragms force-length relationship in CAPD patients, although this mechanism is insufficient to prevent a reduction of neuromechanical efficiency of the diaphragm.