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

Surgical stress and general anesthesia can suppress immune function and thus may increase postsurgical infections and tumor metastasis. We previously reported that two narcotics commonly used in high-dose opiate anesthesia (fentanyl and sufentanil) suppress natural killer (NK) cell activity in rats. Such doses of narcotics also cause respiratory depression accompanied by hypoxia, hypercarbia, and acidosis, which might account for the observed narcotic-induced NK suppression. In the present study, we compared the effects of fentanyl on NK activity in ventilated and non-ventilated rats. Fentanyl significantly suppressed NK cell activity to the same magnitude in the two groups, although the groups significantly differed in CO2 and O2 levels. The fact that high-dose fentanyl-induced NK suppression can be demonstrated in ventilated rats accentuates the relevance of these findings to clinical studies showing NK suppression in the immediate postoperative period. Such immunosuppression could be a risk factor for patients undergoing surgery, especially in cancer-related operations.
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PMID:Narcotic-induced suppression of natural killer cell activity in ventilated and nonventilated rats. 164 47

High-frequency jet ventilation has been reported as an effective method of ventilation during laryngoscopy, but may expose the patient to the risks of barotrauma or alveolar hypoventilation. The aim of the study was to evaluate the determining factors of pulmonary complications under high-frequency jet ventilation in 83 patients undergoing laryngoscopy for upper airway cancer. Pulmonary distention was mainly influenced by upper airway obstruction score (p = .0001), while patients with chronic obstructive pulmonary disease (COPD) did not suffer from gas trapping. Impaired gas exchange was predicted by increased weight (p = .0001), smaller injector diameter (p = .02), and lower airway obstruction (p = .001). Hypercapnia occurred in both upper and lower airway obstruction, while hypoxemia was principally observed in COPD patients. Emphasis is placed on monitoring by pulse oximetry, end-expiratory pressure, and PCO2 measurement, especially in patients with obesity, COPD, or upper airway obstruction.
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PMID:Airway obstruction and high-frequency jet ventilation during laryngoscopy. 174 28

Acute respiratory failure (ARF) in an 11-year-old child with pre-T acute lymphoblastic leukemia (ALL) at the beginning of induction therapy was observed, connected with a pulmonary thrombosis and not with an infective origin. A systematic search for this pathology identified six other children with the same pulmonary complication, five of whom where in the early phase of acute nonlymphoblastic leukemia (ANLL) and one in induction therapy for ALL in marrow relapse. At the beginning of the symptomatology, all children presented severe hypoxia and hypercapnia, with no or minimal chest radiograph abnormalities and no clear hemodynamic involvement. In all patients the arteriography and nuclear imaging studies confirmed the diagnosis. The causes of the thrombi could be connected with neoplastic emboli after cell lysis and/or with the vascular damage resulting from antiblastic therapy. Intravenous urokinase treatment and respiratory assistance had been successfully carried out in six of seven children.
Cancer 1991 Feb 01
PMID:Acute respiratory failure and pulmonary thrombosis in leukemic children. 198 61

Two cases of paralysis of the diaphragm occurring after puncture of the internal jugular vein are reported. Both were old cancer patients, requiring an internal jugular venous catheter for intravenous feeding. Although the catheter was easily placed in both cases, the diagnosis of diaphragmatic paralysis was made postoperatively. The first patient remained asymptomatic, despite paradoxical breathing when lying supine; there was no change in her condition up to her death 4 months later. The second patient became increasingly breathless, with hypoxia and hypercapnia, during recovery from a gastrostomy under general anaesthesia. She required artificial ventilation, from which she could not be weaned and died 25 days later. A lesion of the phrenic nerve is possible when placing an internal jugular venous catheter, because they are closely related behind the sternocleidomastoid muscle. In the opposite to compression by a haematoma, or transient blockade following local anaesthetic infiltration, such a direct injury may be irreversible.
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PMID:[Diaphragmatic paralysis after puncture of the internal jugular vein]. 200 74

The ability to manage acute airway obstruction can be life-saving. Airway relief should be expeditious and immediate, with low morbidity and mortality. It should not interfere with future definitive therapy. In patients with terminal malignancy, it should be economical in cost and should minimize hospitalization. We used biopsy forceps and the rigid bronchoscope to "core out" 56 patients with obstructing airway neoplasms. The location of the obstruction was trachea in 16 patients, carina in 24, main bronchi in 8, and distal airway in 8. Improvement in the airway was accomplished in 90% of patients. A single bronchoscopy was sufficient in 96%. Nineteen complications occurred in 11 patients: pneumonia in 5, bleeding in 3, pneumothorax in 2, hypoxia/hypercarbia in 2, arrhythmias in 6, and laryngeal edema in 1. There were four deaths within 2 weeks of core-out related to respiratory failure. Further therapy consisted of resection in 28.6% (tracheal in 9, carinal in 3, pulmonary in 4), irradiation alone or in combination with chemotherapy in 60.7%, and no therapy in 10.7%. Palliation of symptoms and establishment of an airway in acute obstruction is the goal. Survival depends on the effectiveness of the proposed treatment. We find this time-honored method superior to use of the laser.
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PMID:Endoscopic relief of malignant airway obstruction. 247 87

Three children developed severe respiratory distress at days +12, +11, and +11 following allogeneic bone marrow transplantation from donors. The first child was a 13-year-old Hispanic boy transplanted in relapse of Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL). At day -14, a bronchial washing done for a streaky pulmonary infiltrate was negative for acid-fast bacilli. Miliary tuberculosis was discovered at postmortem examination. A second child, transplanted in remission of null-cell ALL, developed severe hypoxia and hypercarbia on day +11 but recovered fully following prolonged mechanical ventilation. An open-lung biopsy showed a pattern of nonspecific, diffuse alveolar damage compatible with respiratory distress syndrome. The third child was transplanted in remission of B-cell ALL and developed fatal fungal and cytomegalovirus pneumonia on day +12. In these latter two cases, it is likely that open-lung biopsy would have missed the diagnosis because of the uneven pulmonary involvement and multiple etiologies observed. All three children received cyclosporine, granulocyte transfusions, and multiple antimicrobials, including amphotericin B. Hyperfractioned total-body irradiation with lung shielding was used in the latter two patients.
Cancer Detect Prev Suppl 1987
PMID:Difficulty in establishing diagnosis from lung biopsies and bronchial washing analysis in children with leukemia following bone marrow transplantation. 331 45

The tumor interstitial pH and its modification play a significant role in cancer treatment. Current in vivo pH measurement techniques are invasive and/or provide poor spatial resolution. Therefore, there are no data on perivascular interstitial pH gradients in normal or tumor tissue. We have optically measured interstitial pH gradients with high resolution in normal and tumor (VX2 carcinoma) tissue in vivo by combining a fluorescence ratio imaging microscopy technique and the rabbit ear chamber preparation. The strengths of our approach include the ability to follow pH in the same location for several weeks and to relate these measurements to local blood flow and vascular architecture. Our results show: (a) tumor interstitial pH (6.75 units; N = 6 animals, n = 324 measurements) is significantly (P < 0.001) less than normal interstitial pH (7.23; N = 5, n = 274). This increased acidity in the tumor interstitium is in agreement with the previously reported data on this tumor; (b) with respect to pH spatial gradients in normal tissue, the interstitial pH decreased by approximately 0.32 pH units over a distance of 50 microns away from the blood vessel, while in tumor tissue, interstitial pH decreased by approximately 0.13 units over the same distance. Although the pH gradient near the vessel wall was steeper in normal tissue compared to tumor, the proton concentration gradient in normal tissue was less than that in the tumor. The approximate increase in proton concentration from 0-50 microns from the vessel was 4.5 x 10(-8)M in normal versus 5.7 x 10(-8)M in tumor tissue; (c) a simple one-dimensional diffusion-reaction model suggested that tumor tissue was producing protons at a rat 65-100% greater than normal tissue; (d) feasibility studies of temporal dynamics resulting from hyperglycemia (6 g/kg) or hypercapnia (10% CO2) led to significant (P < 0.05) interstitial pH reductions. During hyperglycemia, pH dropped by more than 0.2 pH units in about 90 min in tumor tissue but remained constant in normal tissue. Hypercapnia dramatically reduced pH by approximately 0.3 pH units in tumor tissue. Our limited studies on hyperglycemia and hypercapnia are in agreement with the previously published studies and demonstrate the capability of fluorescence ratio imaging microscopy to measure spatial as well as temporal changes in interstitial pH. Fluorescence ratio imaging microscopy should permit noninvasive evaluation of new pH-modifying agents and offer unique mechanistic information about tumor pathophysiology in tissue preparations where the surface of the tissue can be observed.
Cancer Res 1994 Nov 01
PMID:Noninvasive measurement of interstitial pH profiles in normal and neoplastic tissue using fluorescence ratio imaging microscopy. 792 15

The medical hazards of obesity are discussed. Risks include insulin resistance, diabetes mellitus, hypertriglyceridemia, decreased levels of high-density lipoprotein cholesterol, and increased levels of low-density lipoprotein cholesterol. Obesity is also associated with gallbladder disease and some forms of cancer as well as sleep apnea, chronic hypoxia and hypercapnia, and degenerative joint disease. Obesity is an independent risk factor for death from coronary heart disease. A central distribution of body fat enhances the risk for most of these conditions.
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PMID:Medical hazards of obesity. 836 92

The adult (acute) respiratory distress syndrome is a significant cause of morbidity in children. The mortality rates remain elevated, greater than 50%, and even greater than 80% in patients with underlying malignancies. The therapeutic interventions remain mainly supportive. Strategies of conventional mechanical ventilation are directed toward the use of high positive end-expiratory pressures, low positive inspiratory pressure, and permissive hypercapnia. High-frequency oscillatory ventilation and tracheal insufflation are not yet used extensively, although they should contribute to less aggressive ventilation. Surfactant replacement, nitric oxide inhalation, and partial liquid ventilation seem to be promising technologies, but controlled clinical studies are necessary before their wide-spread use. Extracorporeal membrane oxygenation remains the alternative technology in case of failure of conventional support.
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PMID:Acute respiratory distress syndrome in children. 922 57

Tumour blood flow is one of the important factors limiting the efficacy of radiation therapy (hypoxic radioresistance), chemotherapy (drug delivery) and thermal therapy (heat dissipation) in treating cancer. The modification of tumour blood flow has been an area of intense investigation. In the current study, the arterial carbon dioxide tension (PaCO2) was changed in order to investigate the tumour vascular response to carbon dioxide. Functional maps of blood flow, blood volume and mean transit time were generated at four PaCO2 levels in VX2 tumour in the rabbit thigh and normal soft tissue. The PaCO2 levels investigated were normocapnia (PaCO2 = 40.9 +/- 1.2 mmHg), hypocapnia (27.2 +/- 2.3 and 33.5 +/- 2.3 mmHg) and hypercapnia (54.9 +/- 4.4 mmHg). The carbon dioxide reactivity of the global tumour blood flow and mean transit time showed significant differences between normocapnia and the two levels of hypocapnia, but not between normocapnia and hypercapnia. The average fractional change of blood flow from normocapnia for the two levels of hypocapnia was -0.41 +/- 0.06 and -0.29 +/- 0.08, respectively (P < 0.05). In the case of mean transit time the fractional change was +0.39 +/- 0.30 and +0.23 +/- 0.24, respectively (P < 0.05). The fractional change of blood volume from normocapnia, however, was not significantly different at any capnic level, as was the case with respect to each of the functional parameters in normal tissue. The ability to reduce blood flow and increase mean transit time through hypocapnia has significant implications in thermal therapy, since heat dissipation is a major factor in limiting the effectiveness of treatment.
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PMID:Carbon dioxide reactivity of computed tomography functional parameters in rabbit VX2 soft tissue tumour. 1270 90


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