Usefulness of continuous oxygen insufflation into trachea for management of upper airway obstruction during anesthesia.
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BACKGROUND: Severe complications associated with upper airway obstruction often occur during the perioperative period. Development of a simple and reliable technique for reversing the impaired airway patency may improve airway management. The purpose of the current study is to evaluate the usefulness of transtracheal oxygen insufflation (TTI) for management of upper airway obstruction during anesthesia and to explore the mechanisms of TTI in detail. METHODS: During propofol anesthesia in eight spontaneously breathing patients, the upper airway cross-sectional area and pressure-flow measurements during neck flexion with TTI were compared with those during triple airway maneuvers (TAM) without TTI. Blood gas analyses assessed efficacy of CO2 elimination during TTI in an additional nine patients. RESULTS: TTI achieved adequate PaCO2 and PaO2 levels equivalent to those during TAM. In addition to a significantly smaller cross-sectional area during TTI, the location and slope of the pressure-flow relation during TTI completely differed from those during TAM, indicating that upper airway resistance was much higher during TTI. Notably, minute ventilation during TTI was significantly smaller than that during TAM, suggesting reduced dead space or other mechanisms for CO2 elimination. CONCLUSIONS: TTI is capable of maintaining adequate blood gases through mechanisms different from those of conventional airway support in anesthetized subjects with upper airway obstruction. (+info)
Tracheobronchial involvement in relapsing polychondritis.
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Relapsing polychondritis (RPC) is a multisystem disorder of chondromalacia involving any cartilage. Respiratory tract involvement is the greatest threat to life. We report a patient with stenosis of the subglottic trachea and left main bronchus who suddenly ceased breathing. As this patient did not have any other clinical features of RPC, the diagnosis was difficult. CT showed circumferential worm-eaten-like thickening suggesting a deformity and edema of the tracheal mucosa. Biopsy of the tracheal and thyroid cartilage revealed mild cartilage degeneration and infiltration with inflammatory cells. Therefore, the patient was diagnosed as having RPC. She is currently well 24 months after Montgomery T tube intubation with systemic steroids. Narrowing of the left main bronchus has not worsened. (+info)
High-dose rate brachytherapy of bronchial cancer: treatment optimization using three schemes of therapy.
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PURPOSE: Our aim is to demonstrate that a fractionated high-dose rate endobronchial brachytherapy (HDRBT) treatment is tolerable for patients with advanced (IIIA-IIIB) non-small cell lung cancer and gives an improvement of symptoms. Patients and Methods. From January 1992 to July 1997, we treated 320 patients with external beam radiotherapy (EBRT) and concomitant HDRBT with Ir192. Eighty-four patients received 10 Gy in one fraction from January 1992 to March 1993 (Group A); 47 patients received two fractions of 7 Gy each from April 1993 to December 1993 (Group B), and 189 patients received three fractions of 5 Gy each from January 1994 to July 1997 (Group C). RESULTS: Mean survival from diagnosis is 11.1 months and mean survival from last HDRBT is 9.7 months. The symptomatic response rate is 90% for dyspnea, 82% for cough, 94% for hemoptysis and 90% for obstructive pneumonia. Performance status was improved in 70% of patients. Follow-up is in the range of 5-36 months with 280/320 evaluable patients (87.5%) (40 patients were lost to follow-up). For the patients treated with three fractions of HDRBT plus EBRT, a smaller number of side effects occurred while relief from symptoms linked to bronchial obstruction and survival was similar for the three groups. CONCLUSIONS: A three-fraction brachytherapy results in fewer side effects, such as bronchial fibrosis with or without stenosis, while survival and symptomatic relief are similar in the three groups treated. (+info)
Metabolic consequences of adenosine deaminase deficiency in mice are associated with defects in alveogenesis, pulmonary inflammation, and airway obstruction.
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Adenosine deaminase (ADA) is a purine catabolic enzyme that manages levels of the biologically active purines adenosine and 2'-deoxyadenosine in tissues and cells. ADA-deficient mice die at 3 wk of age from severe respiratory distress. This phenotype is progressive and is linked to perturbations in pulmonary purine metabolism. The inflammatory changes found in the lungs of ADA-deficient mice included an accumulation of activated alveolar macrophages and eosinophils. These changes were accompanied by a pronounced enlargement of alveolar spaces and increases in mucus production in the bronchial airways. The alveolar enlargement was found to be due in part to abnormal alveogenesis. Lowering adenosine and 2'-deoxyadenosine levels using ADA enzyme therapy decreased the pulmonary eosinophilia and resolved many of the lung histopathologies. In addition, genetically restoring ADA to the forestomach of otherwise ADA-deficient mice prevented adenine metabolic disturbances as well as lung inflammation and damage. These data suggest that disturbances in purinergic signaling mediate the lung inflammation and damage seen in ADA-deficient mice. (+info)
Comparison of aerosol ipratropium bromide and salbutamol in chronic bronchitis and asthma.
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The effects of inhaling 200 mu g of salbutamol were compared with those of inhaling 40 mu g of ipratropium bromide singly and in combination with salbutamol in eight patients with bronchitis and eight asthmatic patients in a double-blind controlled trial. Changes in airways resistance were assessed by measuring the forced expiratory volume in 1 second and specific airways conductance. Both drugs were significantly better in relieving airways obstruction than placebo. Salbutamol was significantly more effective than ipratropium bromide in patients with asthma, but in the patients with bronchitis there was no significant difference between salbutamol and ipratropium bromide. The combination of the two drugs produced a slightly greater and longer response than either drug alone but this was not significant. (+info)
Movement of criticall ill patients within hospital.
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Critically ill patients were observed during routine movement inside the hospital to and from the intensive therapy unit. One patient a month suffered major cardiorespiratory collapse or death as a direct result of movement. Renewed bleeding of a pelvic fracture, cardiac arrhythmia, cardiac embarrassment due to a haemothorax, and cardiovascular decompensation were seen. It was difficult to continue treatment during movement, especially maintaining an airway or providing adequate intermittent positive pressure ventilation. Seventy postoperative patients suffered few ill effects on being moved. Greater awareness of the dangers of moving critically ill patients within hospital is needed. Thorough preparation for the move and adequate maintenance of treatment during movement requires the skill of experienced medical staff. (+info)
Airway obstruction and chronic exertional dyspnoea in patients with persistent bronchial asthma.
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In patients with COPD, flow limitation (FL) predicts chronic exertional dyspnoea (CED) better than routine spirometry. Whether, and to what extent, FL and CED are overlapping quantities in chronic asthma has not yet been defined. Forty consecutive clinically stable asthmatic patients without smoking history or cardiopulmonary disorders, were studied. In each subject respiratory function, including static and dynamic pulmonary volumes, was evaluated; maximal (MEFV) and partial (PEFV) expiratory V'-V curves and isovolumic partial to maximal flow ratio (M/P). FL was assessed in a seated patient by comparing tidal and PEFV curves; FL was detected when tidal flows were superimposed or exceeded those obtained during PEFV curves, and was expressed as a percentage of the expired control tidal volume (V(T)) affected by flow limitation (FL% VT). Dyspnoea was assessed by both MRC scale and Baseline Dyspnoea Index (BDI) focal score. Half of the patients were found to have FL. They were older, more dyspnoeic and more obstructed (P<0.03 - P<0.000005) than the non-FL group. FEV1, vital capacity (VC), age, body mass index, FL and M/P ratio were all related to dyspnoea scores. FL was significantly related to FEV1 (r = - 0.59). Multiple regression analysis showed that FEV1 (P=0.003, r2= 15-3% and P = 0.004, r2= 20.3%) and age (P = 0.0006, r2 = 26.8% and P = 0.016, r2 = 11%) independently predicted a part of the variance of MRC (P = 0.0001, r2 = 42.1%) and BDI (P = 0.0008, r2 = 31.3%), respectively. With dyspnoea scale being the gold standard, diagnostic accuracy (sensitivity and specificity) by ROC (receiver operating characteristics) analysis was similar for FEV1 and FL. The results indicate that FL may be present in this subset of asthmatics. CED may not be easily explained by abnormalities of routine spirometry or FL, the largest part of the CED variance remained unexplained. Thus, routine spirometry, FL and CED in patients with bronchial asthma are only partially overlapping quantities which need to be assessed separately. (+info)
Myogenic and scalp signals evoked by midinspiratory airway occlusion.
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A somatosensory potential that is evoked by transient added inspiratory load has previously been described (Davenport PW, Friedman WA, Thompson FJ, and Franzen O. J Appl Physiol 60: 1843-1848, 1986). This evoked potential is novel because it arises in response to a stimulus that also evokes a muscle response, and so this potential could contain myogenic components. The present study was undertaken to define the relationship between the scalp response and other physiological responses that are evoked by airway occlusion. Evoked signals were recorded from the scalp, scalenus anterior, masseter, and electrooculogram. Responses to a 200-ms midinspiratory occlusion were recorded in 12 healthy volunteers. Evoked responses were reliably recorded at C(3)-C(Z) and C(4)-C(Z) and from the skin overlying the scalenus anterior in 11 of these subjects. The onset latencies were 15.7 +/- 3.1 at C(3)-C(Z), 15.9 +/- 2.1 at C(4)-C(Z), and 17.6 +/- 5.5 ms at scalenus anterior. In nine subjects, the masseter response appeared to coincide with the mouth pressure trace, and this was interpreted as movement artifact. No consistent electrooculogram or frontal electroencephalogram response was recorded. Because of the similarity in onset latency at C(3)-C(Z), C(4)-C(Z), and scalenus anterior, it was concluded that the myogenic signal may contribute to the scalp response and should be viewed as a potential source of artifact in experiments of this nature. (+info)