Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020440 (hypercapnia)
 7,939 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of beta-adrenoceptor antagonists on the respiratory response to carbon dioxide rebreathing was studied in eight normal subjects. Propranolol, atenolol, metoprolol, and placebo were given in random, double-blind fashion. Subjects were studied before each treatment period, after one dose, and after eight days of treatment with each drug. A rebreathing method was used to produce progressive hypercapnia and the respiratory response was assessed by measuring minute ventilation and maximum rate of change of inspiratory mouth pressure. Beta-blockade was assessed by the reduction in heart rate during steady state exercise on a cycle ergometer. There was no change in the respiratory response to carbon dioxide after a single dose or eight days treatment of any drug. All three active drugs produced a significant reduction in exercise heart rate. The forced expiratory volume in one second was not altered by any of the drugs.
Thorax 1980 Nov
PMID:Effect of acute and chronic beta-blockade on carbon dioxide sensitivity in normal man. 678 64

In a study of 100 patients undergoing rigid bronchoscopy under intravenous general anaesthesia with oxygen Venturi ventilation no major complications were observed. Minor complications included one adverse reaction to alphaxalone-alphadolone acetate (Althesin), one prolonged episode of laryngeal spasm after removal of the bronchoscope, and subsequent muscle pain attributed to suxamethonium in 36 patients. The last complication occurred significantly less frequently (p less than 0 . 025) in those patients who were pretreated with a small dose of a non-depolarising neuromuscular blocking agent. Serial arterial blood gas sampling in 10 patients showed adequate ventilation during bronchoscopy, but carbon dioxide retention developed in nine cases immediately after the bronchoscope was withdrawn. With adequate precautions, however, the procedure is safe and well tolerated, even in patients with severe impairment of respiratory function.
Thorax 1982 Jul
PMID:Rigid bronchoscopy under intravenous general anaesthesia with oxygen Venturi ventilation. 681 87

Baroreceptor sensitivity, reflected by the slope of the linear regression of the electrocardiographic R-R interval on the rise of systolic blood pressure after injection of phenylephrine, was significantly lower in 27 patients with chronic obstructive pulmonary disease (4.67 +/- 2.67) than in 10 normal subjects (12.07 +/- 3.3) of comparable age (p less than 0.001). In 20 patients in whom right heart catheterisation was performed, pulmonary artery pressure was inversely related to baroreflex sensitivity (r = - 0.603, p less than 0.01). Independent variables such as arterial Po2, Pco2, and mean pulmonary artery pressure were examined in order to assess their ability to predict baroreflex sensitivity. The independent variable that made the most significant contribution was mean pulmonary artery pressure. It seems that the attenuation of baroreflex response in patients with chronic obstructive pulmonary disease is caused mainly by pulmonary hypertension and partly by the central effects of hypoxia and hypercapnia.
Thorax 1982 Apr
PMID:Reduced baroreceptor sensitivity in patients with chronic obstructive pulmonary disease. 711 59

Fourteen male patients with chronic bronchitis and hypoxia had a lateral radiograph of the pituitary fossa. Nine of the 14 had definite or probable abnormalities, a significantly higher frequency (p less than or equal to 0.01) than is represented by the two out of 14 age-matched men from a control group with head injuries. The most common change was thinning or erosion of the lamina dura. Patients with hypercapnia were no more prone to such abnormalities than were those with normocapnia, a finding that conflicts with a previous paper. We confirm that radiological pituitary fossa changes do occur in chronic bronchitis, that they are unrelated to steroid treatment, and that they are probably not solely due to the chronically raised intracranial pressure associated with hypercapnia. Other possible mechanisms are discussed--in particular hypoxia, which might produce changes on account of the increased cerebral blood flow and engorged intracranial blood vessels.
Thorax 1982 Jul
PMID:Radiological pituitary fossa changes in chronic bronchitis. 713 92

To investigate the role of endorphins in central respiratory control, the effect of naloxone, a specific opiate antagonist, on resting ventilation and ventilatory control was investigated in a randomised double-blind, placebo-controlled study of normal subjects and patients with chronic airways obstruction and mild hypercapnia due to longstanding chronic bronchitis. In 13 normal subjects the ventilatory response to hypercapnia increased after an intravenous injection of naloxone (0.1 mg/kg), ventilation (VE) at a PCO2 of 8.5 kPa increasing from 55.6 +/- SEM 6.2 to 75.9 +/- 8.21 min-1 (p less than 0.001) and the delta VE/delta PCO2 slope increasing from 28.6 +/- 4.4 to 34.2 +/- 4.21 min-1 kPa-1 (p less than 0.05). There was no significant change after placebo (saline) injection. Naloxone had no effect on resting ventilation or on the ventilatory response to hypoxia in normal subjects. In all six patients naloxone significantly (p less than 0.02) increased mouth occlusion pressure (P 0.1) responses to hypercapnia. Although there was no change in resting respiratory frequency or tidal volume patients showed a significant (p less than 0.01) decrease in inspiratory timing (Ti/Ttot) and increase in mean inspiratory flow (VT/Ti) after naloxone. These results indicate that endorphins have a modulatory role in the central respiratory response to hypercapnia in both normal subjects and patients with airways obstruction. In addition, they have an inhibitory effect on the control of tidal breathing in patients with chronic bronchitis.
Thorax 1982 Nov
PMID:Endogenous opiates and the control of breathing in normal subjects and patients with chronic airflow obstruction. 716 1

Three children and two young adults with severe asthma who had frequent episodes of respiratory failure were studied. Isocapnic hypoxia and hyperoxic hypercapnia were produced separately using a rebreathing apparatus. Alveolar carbon dioxide tension and oxygen tension were estimated by continuously sampling expired gases. The three young children had a diminished response to hypoxia but a normal response to hypercapnia when compared to control asthmatic children (p less than 0.05) or healthy children (p less than 0.05). The two young adult patients had a normal response to hypoxia but one had a low response to hypercapnia. Studies of parents of these patients suggested that the chance combination of a possibly familial, inappropriate response to hypoxia with severe asthma would lead to a risk of respiratory failure.
Thorax 1981 Oct
PMID:Hypoxic and hypercapnic response in asthmatic subjects with previous respiratory failure. 733 Jul 94

Clear guidelines for the selection of patients with large pulmonary bullae and severely impaired lung function for surgery remain to be defined. Twenty-one such patients operated on between 1971 and 1977 are reviewed in an attempt to shed some light on this difficult problem. Four of six patients with preoperative hypercapnia survived and were improved by surgery. There was no mortality among the remaining 15 patients of whom 14 were improved symptomatically by surgery (with improvement in FEV1 and vital capacity in 9). Preoperative bronchograms were used to help identify patients suitable for surgery. The presence of bronchiectasis was predictive of postoperative complications. Better results were obtained in those patients in whom plication of bullectomy could be performed than in those requiring lobectomy.
Thorax 1981 Dec
PMID:Surgical treatment of bullous lung disease. 733 65

There are currently three surgical treatments for emphysema: bullectomy, lung transplantation, and lung volume reduction surgery (LVRS). Unfortunately, most emphysema patients are poor candidates for any surgical intervention. A meticulous selection process is favoured in which indications and contraindications are considered and the best solution is devised for each patient. Patients with giant bullae filling half the thoracic volume and compressing relatively normal adjacent parenchyma are offered bullectomy; those with hyperinflation, heterogeneous distribution of destruction, forced expiratory volume in 1 second (FEV(1)) >20%, and a normal carbon dioxide tension (PCO(2)) are offered LVRS; and patients with diffuse disease, lower FEV(1), hypercapnia, and associated pulmonary hypertension are directed towards transplantation. Using these criteria, few patients are serious candidates for surgical procedures. Combinations of LVRS and lung transplantation, either simultaneously or sequentially, are possible but rarely necessary.
Thorax 2003 Jul
PMID:Chronic obstructive pulmonary disease. 10: Bullectomy, lung volume reduction surgery, and transplantation for patients with chronic obstructive pulmonary disease. 1283 85

Chronic respiratory insufficiency is inevitable in the course of disease progression in patients with Duchenne muscular dystrophy (DMD). Without mechanical ventilation (MV), morbidity and mortality are highly likely towards the end of the second decade of life. The present review reports evidence and clinical implications regarding DMD patients treated with MV. There is no doubt that nocturnal hypercapnia precedes daytime hypercapnia. Historical comparisons have provided evidence that non-invasive intermittent positive pressure ventilation (NIPPV) at night is effective and improves quality of life and survival by 5-10 years. By contrast, the optimal criteria and timing for initiation of NIPPV are inconsistent. A recent randomized study however demonstrated the benefits of commencing NIPPV as soon as nocturnal hypoventilation is detected (Ward S, et al., Randomised controlled trial of non-invasive ventilation (NIV) for nocturnal hypoventilation in neuromuscular and chest wall disease patients with daytime normocapnia. Thorax 2005; 60: 1019-24). The respective role of the three hypotheses of the indirect action of nocturnal NIPPV on daytime blood gases may be complimentary; the main improvement may be due to improved ventilatory response to CO2. The ultimate time to offer full time ventilation with the most advantageous interface is lacking in evidence. Full time NIV is possible with a combination of a nasal mask during the night and a mouthpiece during the day, however tracheostomy may be provided when mechanical techniques of cough-assistance are useless to treat chronic cough insufficiency.
 ...
PMID:Mechanical ventilation in Duchenne patients with chronic respiratory insufficiency: clinical implications of 20 years published experience. 1771 17

Congenital central hypoventilation syndrome most commonly presents in neonates with sleep related hypoventilation; late onset cases have occurred up to the age of 10 years. It is associated with mutations in the PHOX2B gene, encoding a transcription factor involved in autonomic nervous system development. The case history is described of an adult who presented with chronic respiratory failure due to PHOX2B mutation-associated central hypoventilation and an impaired response to hypercapnia.
Thorax 2007 Oct
PMID:Central hypoventilation with PHOX2B expansion mutation presenting in adulthood. 1790 90


<< Previous 1 2 3 4 Next >>