In Caucasians and Native Americans living at altitude, hemoglobin mass is increased in spite of erythropoietin concentrations ([Epo]) not markedly differing from sea level values. We hypothesized that a nocturnal decrease of arterial oxygen saturation (SaO2) causes a temporary rise of [Epo] not detected by morning measurements. SaO2 (continuous, finger oximeter) and [Epo] (ELISA, every 4 h) wer...

Arterial blood gas tensions, pH, and carboxyhaemoglobin were measured on 322 occasions in 165 patients and the actual oxygen saturation of the haemoglobin (Sao2) was compared with the ear oxygen saturation (SEO2) recorded during the arterial sampling with a Biox IIA ear oximeter. The overall agreement between SEO2 and Sao2 was good, with a mean difference in saturation (SEO2-Sao2) of + 1.5% (SD...

It is probable that some daily activities may cause marked falls in arterial oxygen saturation (SaO2) in patients undergoing long-term oxygen therapy (LTOT), despite good oxygenation at rest. We estimated the adequacy of LTOT in 34 randomly selected chronic obstructive pulmonary disease (COPD) patients at home by monitoring SaO2 continuously over 24 h. The subjects were also asked to complete a...

Inhaled sympathomimetic agents are often used in bronchiolitis with little objective evidence of benefit. The arterial oxygen saturation (SaO2) reflects the adequacy of ventilation-perfusion balance. The aim of the current study was to determine the effect of inhaled salbutamol on SaO2. In a randomised, double blind study, 21 infants, admitted with bronchiolitis positive for respiratory syncyti...

Background: Right Ventricular (RV) hypertrophy is an adaptive response to chronic RV pressure overload in patients with pulmonary hypertension. We investigated the relationships between RV hypertrophy indicators, including electrocardiography, the percentage oxygen saturation (SaO2%), body mass index (BMI), and blood uric acid levels in patients with...

A range of variation in percent of oxygen saturation of arterial hemoglobin (SaO2) among healthy individuals at a given high altitude indicates differences in physiological hypoxemia despite uniform ambient hypoxic stress. In populations native to the Tibetan plateau, a significant portion of the variance is attributable to additive genetic factors, and there is a major gene influencing SaO2. T...

BACKGROUND Hepatopulmonary syndrome (HPS) is a rare complication of liver diseases of different etiologies and may indicate a poor prognosis. Therefore, a simple non-invasive screening method to detect HPS would be highly desirable. In this study pulse oximetry was evaluated to identify patients with HPS. METHODS In 316 consecutive patients with liver cirrhosis (n = 245), chronic hepatitis (n...

Arterial oxygen saturation (SaO2) was analysed continuously before and for 24 h after lower abdominal surgery in 30 patients breathing air using one of three postoperative analgesic regimens: i.v. diamorphine using a patient-controlled analgesia system (PCAS), extradural diamorphine or i.m. morphine. Hypoxaemia was defined as SaO2 less than 94% for more than 6 min h-1. Before operation there wa...

BACKGROUND It is uncertain whether skin pigmentation affects pulse oximeter accuracy at low HbO2 saturation. METHODS The accuracy of finger pulse oximeters during stable, plateau levels of arterial oxygen saturation (Sao2) between 60 and 100% were evaluated in 11 subjects with darkly pigmented skin and in 10 with light skin pigmentation. Oximeters tested were the Nellcor N-595 with the OxiMax...