Clinical exercise testing in chronic airflow limitation.

D D Marciniuk; C G Gallagher

doi:10.1016/s0025-7125(05)70454-5

Home/Archive/PubMed

PubMed · 8637304

Clinical exercise testing in chronic airflow limitation.

D D Marciniuk·C G Gallagher

View original source ↗Export metadata ↓

Abstract

Exercise testing has become an essential tool in the management of patients with CAL. In addition to its ability to assess exercise limitation objectively, it has usefulness in detecting the presence or absence of associated disease processes, in assessing the response to therapies, in allowing assessment of the importance of psychological factors in exercise limitation, and in guiding prescription for exercise rehabilitation programs. Although much is known about the clinical usefulness of exercise testing in this disease, and much has been learned about how this disease functionally impairs the exercise capacity of the patient, additional study is necessary to appreciate fully the physiologic abnormalities demonstrated by patients with CAL during exercise.

Explore related subjects

Cardiac Output Exercise Exercise Test Humans Lung Diseases, Obstructive Oxygen Consumption Pulmonary Gas Exchange Respiration Respiratory Muscles Journal Article Research Support, Non-U.S. Gov't Review

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

D D Marciniuk, C G Gallagher. 1996. Clinical exercise testing in chronic airflow limitation.. https://doi.org/10.1016/s0025-7125(05)70454-5

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2008

Prediction of intrapulmonary right to left shunt with left atrial size in patients with liver cirrhosis.

BACKGROUND: We screened a large number of liver transplant candidates with contrast echocardiography to detect intrapulmonary right to left shunt (IPS). We found that IPS is frequently present in patients with left atrial enlargement. This finding raises a question concerning the correlation between IPS and left atrial size in patients with liver cirrhosis. OBJECTIVES: The aim of this prospective study was to evaluate the possible correlation between left atrial size and IPS in patients with liver cirrhosis. METHODS: Adult patients (>18 years old) with documented liver cirrhosis underwent trans-thoracic contrast echocardiography with agitated saline. Left atrial dimension was measured by M-mode echocardiography. Stroke volume was calculated using left ventricular M-mode echocardiography. Patients with atrial fibrillation, intracardiac shunt, congenital heart defects, valvular heart disease and diastolic dysfunction were excluded. RESULTS: A total of 92 patients met all study criteria. Of these, 39 (42.3%) had IPS. Cardiac output was significantly greater in patients with IPS compared with those without IPS (5.68 +/- 0.83 L/min vs 4.75 +/- 0.76 L/min, P < 0.01). In a multi-variable model, after adjustment for body surface area and body mass index, left atrial enlargement was the strong predictor of IPS (area under the curve = 0.66) but when controlling for cardiac output, left atrial size was not an independent predictor of IPS. CONCLUSION: In the context of liver cirrhosis, patients with IPS have greater cardiac output compared with those without shunt. Left atrial enlargement, which reflects one aspect of increased cardiac output, is an indirect marker of IPS and greater left atrial dimension is associated with the presence of intrapulmonary right-to-left shunt.

Cardiac Output↗

PubMed2007

Initial orthostatic hypotension: review of a forgotten condition.

Several studies have shown that standing up is a frequent (3-10%) trigger of loss of consciousness both in young and old subjects. An exaggerated transient BP (blood pressure) fall upon standing is the underlying cause. IOH (initial orthostatic hypotension) is defined as a transient BP decrease within 15 s after standing, >40 mmHg SBP (systolic BP) and/or >20 mmHg DBP (diastolic BP) with symptoms of cerebral hypoperfusion. It differs distinctly from typical orthostatic hypotension (i.e. BP decrease >20 mmHg SBP and/or >10 mmHg DBP after 3 min of standing) as the BP decrease is transient. Only continuous beat-to-beat BP measurement during an active standing-up manoeuvre can document this condition. As IOH is only associated with active rising, passive tilting is of no diagnostic value. The pathophysiology of IOH is thought to be a temporal mismatch between cardiac output and vascular resistance. The marked decrease of vascular resistance during rising is similar to that observed at the onset of leg exercise and is absent during head-up tilting. It is attributed to vasodilatation in the working muscle through local mechanisms. Standing up causes an initial increase in venous return through the effects of contraction of leg and abdominal muscles. The consequent sudden increase in right atrial pressure may contribute to the fall in systemic vascular resistance through a reflex effect. This review alerts clinicians and clinician scientists to a common, yet often neglected, condition that occurs only upon an active change of posture and discusses its epidemiology, pathophysiology and management.

Cardiac Output↗

PubMed2006

Importance of luxury flow for critically ill patients receiving a left ventricular assist system.

The presence of a significant organ dysfunction does not immediately exclude patients from consideration for treatment with a left ventricular assist system (LVAS). However, in treating morbid circulatory shock patients with multiple organ failure, it is important to know the preoperative and postoperative factor or factors related to the recovery of the damaged organ function. In this study, we retrospectively analyzed patients receiving a LVAS at our institution and tried to determine the important factors related to the survival of patients with multisystem failure. Twenty-seven patients who underwent LVAS placement at Saitama Medical School Hospital between 1993 and 2003 were included in this study. The preoperative risk factors analyzed were renal dysfunction, respiratory dysfunction, hepatic dysfunction, the existence of active infection, and the combination of all four factors. As a postoperative factor, the pump flow index (mean LVAS pump flow during the first 2 weeks after LVAS surgery divided by the body surface area) was analyzed. None of the analyzed preoperative factors could predict survival after LVAS surgery, but a pump flow index of less than 2.5 l/min/m2 had a significant relationship with death after LVAS surgery. Further analysis revealed that all the patients with a pump flow index of 3.0 l/min/m2 or more could overcome preoperative organ dysfunction. Congestive heart failure patients with multisystem failure need luxury pump flow for successful LVAS surgery; this factor could be especially important in device selection and postoperative management.

Cardiac Output↗