A Case of Medullary Infarct Causing Central Alveolar Hypoventilation

To study the effect of endorphins on metabolic rate and on the relationship between O2 consumption (VO2) and ventilation, we administered enkephalin analogues (relatively selective delta-receptor agonists) and a morphiceptin analogue (a highly selective mu-receptor agonist) intracisternally in nine unanesthetized chronically instrumented adult dogs. Both delta- and mu-agonists decreased VO2 by 40–60%. delta-Agonists induced a dose-dependent decrease in mean instantaneous minute ventilation (VT/TT) associated with periodic breathing. The decrease in VT/TT started and resolved prior to the decrease and returned to baseline of VO2, respectively. In contrast, the mu-agonists induced an increase in VT/TT associated with rapid shallow breathing. Arterial PCO2 increased and arterial PO2 decreased after both delta- and mu-agonists. Low doses of intracisternal naloxone (0.002–2.0 micrograms/kg) reversed the opioid effect on VT/TT but not on VO2; higher doses of naloxone (5–25 micrograms/kg) reversed both. Naloxone administered alone had no effect on VT/TT or VO2. These data suggest that 1) both delta- and mu-agonists induce alveolar hypoventilation despite a decrease in VO2, 2) this hypoventilation results from a decrease in VT/TT after delta-agonists but an increase in dead space ventilation after mu-agonists, and 3) endorphins do not modulate ventilation and metabolic rate tonically, but we speculate that they may do so in response to stressful stimulation.

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Management of Chronic Alveolar Hypoventilation by Nasal Ventilation

CHEST Journal ◽

10.1378/chest.97.1.52 ◽

1990 ◽

Vol 97 (1) ◽

pp. 52-57 ◽

Cited By ~ 173

Author(s):

John R. Bach ◽

Augusta S. Alba

Keyword(s):

Alveolar Hypoventilation

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The Syndrome of Alveolar Hypoventilation and Diminished Sensitivity of the Respiratory Center

New England Journal of Medicine ◽

10.1056/nejm195706202562501 ◽

1957 ◽

Vol 256 (25) ◽

pp. 1165-1170 ◽

Cited By ~ 55

Author(s):

Tor Richter ◽

John R. West ◽

Alfred P. Fishman

Keyword(s):

Respiratory Center ◽

Alveolar Hypoventilation

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Advances in the Management of Acute Asthma in Children

Pediatrics in Review ◽

10.1542/pir.17.7.227 ◽

1996 ◽

Vol 17 (7) ◽

pp. 227-234

Author(s):

Shirley J. Murphy ◽

H. William Kelly

Keyword(s):

Acute Asthma ◽

Airflow Obstruction ◽

Low Flow ◽

Early Introduction ◽

Diagnosis And Management ◽

Current State ◽

Systemic Corticosteroids ◽

Acute Exacerbations ◽

National Heart Lung ◽

Alveolar Hypoventilation

In 1991, the National Heart, Lung and Blood Institute's National Asthma Education Program (NAEP) published "Guidelines for the Diagnosis and Management of Asthma" recommended by an expert panel. This was followed in 1992 by the publication of the "Internal Consensus Report on Diagnosis and Management of Asthma" (ICR). These reports reviewed the current state of knowledge and established the goals of therapy for both chronic asthma and acute exacerbations. This article will provide an update on the research that has been published since those recommendations. The first NAEP guidelines established three goals for the treatment of acute asthma: Rapid reversal of airflow obstruction, correction of significant hypoxemia, and reduction of the rate of recurrent severe asthma symptoms. The ICR added two additional goals: Restoration of lung function to normal as soon as possible and development of a written plan of action in case of a further exacerbation. Both reports concluded that these goals could be accomplished best by aggressive use of inhaled selective beta2-agonists and early introduction of systemic corticosteroids (in certain patients at home). The liberal use of low-flow oxygen was considered safe; it often easily corrects the hypoxemia produced by the alveolar hypoventilation and the mismatch in ventilation/perfusion (V/Q) that frequently accompanies acute asthma exacerbations.

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Gas exchange in healthy rabbits during high-frequency oscillatory ventilation

Journal of Applied Physiology ◽

10.1152/jappl.1989.66.3.1343 ◽

1989 ◽

Vol 66 (3) ◽

pp. 1343-1351 ◽

Cited By ~ 40

Author(s):

B. R. Boynton ◽

M. D. Hammond ◽

J. J. Fredberg ◽

B. G. Buckley ◽

D. Villanueva ◽

...

Keyword(s):

Gas Exchange ◽

High Frequency ◽

High Frequency Oscillatory Ventilation ◽

Blood Gas ◽

Mean Airway Pressure ◽

Oscillatory Ventilation ◽

Dead Space Volume ◽

Alveolar Hypoventilation ◽

High Frequency Oscillatory ◽

Space Volume

We examined the effects of oscillatory frequency (f), tidal volume (VT), and mean airway pressure (Paw) on respiratory gas exchange during high-frequency oscillatory ventilation of healthy anesthetized rabbits. Frequencies from 3 to 30 Hz, VT from 0.4 to 2.0 ml/kg body wt (approximately 20–100% of dead space volume), and Paw from 5 to 20 cmH2O were studied. As expected, both arterial partial pressure of O2 and CO2 (PaO2 and PaCO2, respectively) were found to be related to f and VT. Changing Paw had little effect on blood gas tensions. Similar values of PaO2 and PaCO2 were obtained at many different combinations of f and VT. These relationships collapsed onto a single curve when blood gas tensions were plotted as functions of f multiplied by the square of VT (f. VT2). Simultaneous tracheal and alveolar gas samples showed that the gradient for PO2 and PCO2 increased as f. VT2 decreased, indicating alveolar hypoventilation. However, venous admixture also increased as f. VT2 decreased, suggesting that ventilation-perfusion inequality must also have increased.

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