H Babaali | PubMed Health

PubMed1998

Reference values for pulse oximetry at high altitude.

OBJECTIVE: To determine reference values for oxygen saturation (Sao2) in healthy children younger than 5 years living at high altitude. DESIGN: One hundred and sixty eight children were examined for Sao2 at 4018 m during well child visits. Physiological state was also noted during the examination. RESULTS: The mean Sao2 was 87.3% (95% confidence intervals (CI) 86.7%, 87.9%) with a median value of 87.7%. A significant difference was observed in Sao2 between children younger than 1 year compared with older children, although the difference was no longer demonstrable when sleeping children were excluded. CONCLUSIONS: This study has provided a reference range of Sao2 values for healthy children under 5 years old so that pulse oximetry may be used as an adjunct in diagnosing acute respiratory infections. Younger children were also shown to have a lower mean Sao2 than older children living at high altitude, which suggests physiological adaptation to high altitude over time. In addition, sleep had a lowering effect on Sao2, although the clinical importance of this remains undetermined.

Aging↗

PubMed1989

Determinants of high density lipoprotein cholesterol in middle-aged Seventh-Day Adventist men and their neighbors.

In 1982, high density lipoprotein (HDL) cholesterol and factors known to be or suspected of being associated with HDL cholesterol were measured in 160 middle-aged Seventh-day Adventist men and 160 male neighbors of similar age residing in California. Fish and alcohol consumption, Quetelet index (weight (Ib)/height (in)2), exercise habits, and cigarette smoking were each significantly related to HDL cholesterol levels, in total explaining 17.5% of the variance in the total population and 18.0% of that in the neighbors. Inclusion of three terms representing effect modification between alcohol and exercise, alcohol and Quetelet index, and smoking and Quetelet index and HDL cholesterol increased the explained variance to 25.1% and 31.7% in the total population and in the neighbors alone, respectively. This increase in variance was equivalent to the effect of obesity in the main effects model of all participants or to the effect of obesity and fish consumption together when only the neighbors were considered. Since all product terms included either alcohol or smoking and since exposure to those variables in Adventists was minimal, conclusions were drawn from analyses of the neighbors only. All three product terms were statistically significant in the neighbors. The effect modification that is hence implied suggests that exercise has a particularly strong effect on HDL cholesterol levels in those who drink more alcohol; that alcohol has a greater effect in those who exercise more or who are relatively thin; that obesity may have a greater effect in those who drink more alcohol; that cigarette smoking has a greater effect in those who are relatively obese; and that obesity has a greater effect in those who smoke more cigarettes. In most cases, this suggests synergism between these pairs of variables.

Adult↗