Mean values of normal arterial pH in different species of fish, amphibians and reptiles at 15 and 25 degrees C, taken from the literature, are negatively correlated with arterial P(CO(2)) and plasma [Na(+)]. At either temperature, the data accord with the hypothesis that extracellular acid-base homeostasis evolved to maintain an optimal pH at particular cell-surface sites that are similar in al...

The increased metabolic rate during digestion is associated with changes in arterial acid-base parameters that are caused by gastric acid secretion (the 'alkaline tide'). Net transfer of HCl to the stomach lumen causes an increase in plasma HCO3- levels, but arterial pH does not change because of a ventilatory compensation that counters the metabolic alkalosis. It seems, therefore, that ventila...

BACKGROUND There is an increasing recognition of the potential value of cardiopulmonary exercise testing (CPX) in patients with pulmonary hypertension (PH). Key CPX characteristics in these patients include: (1) a diminished aerobic capacity; (2) an abnormally elevated minute ventilation-carbon dioxide production relationship; and (3) an abnormally diminished partial pressure of end-tidal carbo...

BACKGROUND: Diabetic ketoacidosis (DKA) is a life-threatening endocrine emergency, traditionally requiring arterial blood gas (ABG) analysis for diagnosis and monitoring. The aim of our study was to assess the comparability of arterial and venous blood samples for pH and bicarbonate measurements in patients with DKA. MATERIALS AND METHODS: Prospective, observational study of patients with suspe...

BACKGROUND The objective of this study was to examine the correlation between arterial blood gas (ABG) and peripheral venous blood gas (VBG) samples for all commonly used parameters in patients admitted to a medical intensive care unit (ICU). METHODS A single-center, prospective trial was carried out in a medical ICU in order to determine the level of correlation of ABG and peripheral VBG mea...

Although data from several studies support the use of arginine vasopressin (AVP) for the treatment of hypotension concomitant with pulmonary hypertension (PH) in the cardiac surgery setting, to our knowledge, no previous studies have reported the effect of AVP on the systemic and pulmonary circulation of patients with PH secondary to lung diseases. In this report, we present the hemodynamic res...

A meta-analysis determined whether capillary blood gases accurately reflect arterial blood samples. A mixed effects model was used on 29 relevant studies obtained from a PubMed/Medline search. From 664 and 222 paired samples obtained from the earlobe and fingertip, respectively, earlobe compared to fingertip sampling shows that the standard deviation of the difference is about 2.5x less (or the...

Pulmonary hypertension (PH) is associated with structural and mechanical changes in the pulmonary vascular bed that increase right ventricular (RV) afterload. These changes, characterized by narrowing and stiffening, occur in both proximal and distal pulmonary arteries (PAs). An important consequence of arterial narrowing is increased pulmonary vascular resistance (PVR). Arterial stiffening, wh...

OBJECTIVE This study aims to determine the extent of correlation of arterial and venous pH with a view to identifying whether venous samples can be used as an alternative to arterial values in the clinical management of selected patients in the emergency department. METHODS This prospective study of patients who were deemed by their treating doctor to require an arterial blood gas analysis to...

Arterial blood gas (ABG) analysis has an important role in the clinical assessment of patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). However, arterial puncture or insertion of an arterial catheter has many drawbacks. The aim of this study was to evaluate whether venous blood gas (VBG) values of pH, partial pressure of carbon dioxide (PCO(2)) and oxygen (PO(2...