Acid-Base Response to Chronic Hypercapnia in Man

Brackett, Newton C.; Wingo, Charles F.; Muren, Orhan; Solano, Jose T.

doi:10.1056/nejm196901162800302

Cited by 100 publications

(29 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The presence of hypoxemia, potassium depletion, and other abnormalities might well lead to an He-Paco2 relationship notably different from that observed here. It is of interest, however, to note that in the one published study designed to assess the influence of chronic pulmonary insufficiency upon acute changes in arterial carbon dioxide tension the gross behavior appeared to be similar to that which we have found in the dog, i.e., pH was seemingly defended more effectively than in normal volunteers (16 (17)(18)(19)(20).…”

Section: Methodssupporting

confidence: 64%

The influence of graded degrees of chronic hypercapnia on the acute carbon dioxide titration curve

Goldstein¹,

Gennari²,

Schwartz³

1971

J. Clin. Invest.

View full text Add to dashboard Cite

Section: Methodssupporting

confidence: 64%

The influence of graded degrees of chronic hypercapnia on the acute carbon dioxide titration curve

Goldstein¹,

Gennari²,

Schwartz³

1971

J. Clin. Invest.

View full text Add to dashboard Cite

“…These are often attributed to the presence of a metabolic alkalosis due to diuretics and/or corticosteroids, superimposed on the primary respiratory acidosis. In four earlier studies (7)(8)(9)(10), the degree of acid-base compensation was greater in patients with chronic respiratory acidosis than that described in the canine experiments. However, the patients studied were hospitalized and clinical stability was not defined (10), or was defined as elevated PCO 2 that was stable for only three days (7)(8)(9).…”

mentioning

confidence: 75%

“…As well, patients with disorders likely to cause a superimposed metabolic alkalosis were excluded. Therefore, the findings are of much greater relevance to clinical practice than those from an experimental dog model (3,4) or short term observations in hospitalized patients (7,10). These studies are likely to have underestimated the compensation that patients with chronic respiratory failure may achieve.…”

Section: Discussionmentioning

confidence: 99%

Re‐Evaluation of Acid‐Base Prediction Rules in Patients with Chronic Respiratory Acidosis

Martinu

Menzies

Dial

2003

Canadian Respiratory Journal

View full text Add to dashboard Cite

T Martinu, D Menzies, S Dial. Re-evaluation of acid-base prediction rules in patients with chronic respiratory acidosis. Can Respir J 2003;10(6):311-315. RATIONALE:The prediction rules for the evaluation of the acidbase status in patients with chronic respiratory acidosis, derived primarily from an experimental canine model, suggest that complete compensation should not occur. This appears to contradict frequent observations of normal or near-normal pH levels in patients with chronic hypercapnia. METHODS: Linear regression analysis was used to estimate the relationships between arterial pH, bicarbonate and partial pressure of carbon dioxide (PCO 2 ) from 18 separate arterial blood gas measurements in 18 clinically stable outpatients with chronic hypercapnic respiratory failure from chronic obstructive lung disease, and without clinical conditions or medications likely to cause a primary metabolic alkalosis. RESULTS: The PCO 2 ranged from 45 mmHg to 77 mmHg, and pH ranged from 7.37 to 7.44. In only three of the arterial blood gas measurements were the pH values lower than 7.38. From the regression equations derived from these measurements, the pH decreased by 0.014 for each 10 mmHg increase in the PCO 2 , and the bicarbonate level increased by 5.1 mmol/L. These values are quite different from a decrease in pH of 0.03 and an increase in bicarbonate of 3.5 mmol/L predicted using the rules derived from the canine model. CONCLUSIONS: In patients with chronic stable hypercapnia, acid-base compensatory mechanisms appear to be more effective than would be predicted using the classic rules.

show abstract

“…Careful observations of patients with chronic hypercapnia as a result of chronic obstructive pulmonary disease allowed estimation of a mean ⌬[HCO ]/ ⌬PaCO 2 seems to flatten. 8,9 More recently, a substantially larger slope was reported, but the small number of blood gas measurements, one for each of 18 patients, calls into question the validity of the conclusion reached. 10 …”

Section: Magnitude and Time Course Of The Secondary Responsesmentioning

confidence: 99%