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P Rispens

Publications and source records attributed to P Rispens.

34 records · Page 2Linked to original sources
PubMed1984

On the reliability of the Henderson-Hasselbalch equation in routine clinical acid-base chemistry.

This paper deals with the variability of the practical coefficient of the first ionisation equilibrium of carbonic acid as related to the CO2 in the liquid phase (Henderson-Hasselbalch equation) (Formula: see text) and that of the practical coefficient of the first ionisation equilibrium of carbonic acid as related to the CO2 in the gas phase (modified Henderson-Hasselbalch equation) (Formula: see text).

Acid-Base Imbalance↗
PubMed1981

Calculated changes in pH and pCO2 in arterial blood plasma assuming absence of ion and water exchange between plasma and erythrocytes during their equilibration with alveolar gas.

As a contribution to solving the problem of pH disequilibrium in arterial blood, the results of two modes of gas exchange in the lung have been calculated using an equilibrium state model of the blood. In both cases the HCO3-/Cl-exchange was assumed to occur after the gas exchange in the pulmonary capillaries. When the gas exchange was assumed to be dependent on intra-erythrocytic carbonic anhydrase, the plasma pH in the arterial blood increased. When plasma erythrocytes were assumed to equilibrate separately with the alveolar gas due to pressure of extra-erythrocytic carbonic anhydrase, plasma pH in the arterial blood decreased. In each case there was a slight increase in pCO2 after the blood had left the pulmonary capillaries.

Animals↗
PubMed1978

A new reference method for the determination of the total CO2 concentration in biological fluids.

It appeared that a part of a measuring system recently developed for the determination of the oxygen content of blood (Dijkhuizen, P., Kwant, G. and Zijlstra, W.G. (1976) Clin. Chim. Acta 68, 79), was perfectly suitable for measuring the total CO2 content of blood, plasma or other fluids. CO2-free room air is pumped through an extraction vessel in which all the CO2 of the sample is set free by an acid reagent, and swept by the carrier gas to a titration vessel containing a BaCl2 solution. CO2 is bound as BaCO3 and the ensuing H+ titrated with an NaOH solution. The method was tested by measuring a series of Na2CO3 reference solutions. The values measured by titration amounted to 99.4 +/- 0.8% of the concentration of the reference solutions (range 10--50 mmol 1(-1). The coefficient of variation was 1.8% for 5 mmol 1(-1) solutions and 0.2% for 50 mmol 1(-1) solutions. In measuring a series of 60 blood samples the coefficient of variation as calculated from duplicate determinations was 1%.

Barium↗
PubMed1977

Ionic composition of arterial and mixed venous plasma in the unanesthetized dog.

The use of permanent catheters in the aorta and pulmonary artery permitted the establishment of normal values for hemoglobin concentration in blood and -or pH, PCO2, osmolality, and protein and electrolyte concentrations in the plasma of arterial and venous samples from unanesthetized, undisturbed dogs, and the comparison of the ionic composition of simultaneously taken arterial and venous samples. Arterial samples yielded the following mean values: CHb, 143 g liter-1; pHP, 7.427; PCO2, 32.5 mmHg; CPosmol, 295 mmol kg-1; CPpr, 73.1 g liter-1, CPNa+, 148.0; CPK+, 3.9; CPCa2+, 2.38; CPMg2+, 0.85; CPCl-, 116.0; CPHCO3-, 21.1; CPlact-, 1.4; CPphosph, 1.21; net cation equivalency, 16.4; and anion gap, 1.03 mmol liter-1 in eight male mongrel dogs with seven or eight samplings from each dog. The anion gap in arterial and venous plasma was small, indicating that the contribution of sulfate and organic acids to the ionic composition of dog plasma is quantitatively unimportant. In simultaneously taken arterial and venous samples the following significant arteriovenous differences were found: HP, +0.038; PCO2, -5.6 mmHg; CPosmol, -1.8 mmol kg-1; protein, -0.8 g liter-1; CPNa+, -1.0; CPK+, -0.1; CPCl-, +1.3; and CPHCO3-, -1.7 mmol liter-1. These differences are explained on the basis of the changes that occur in blood upon the addition of CO2 and the ensuing chloride and water shifts.

Animals↗
PubMed1975

Determination of extracellular fluid volume in the dog with ferrocyanide.

The suitability of ferocyanide as an indicator for the measurement of extracellular fluid volume was tested. Added ferrocyanide could be recovered completely from urine, plasma and blood. In in vitro experiments ferrocyanide did not penetrate into erythrocytes, nor did it adhere to the red cell membrane. In gel filtration and electrophoresis experiments binding of ferrocyanide to plasma proteins could not be demonstrated. In in vivo experiments on dogs, the urinary recovery of intravenously administered ferrocyanide was 98.9 +/- 2.1% (n = 14). The partition ratio of ferrocyanide between lymph water and plasma water was 0.99 +/- 0.02 (n = 20). Ferrocyanide could not be detected in cerebrospinal fluid or red cells of dogs after administration by intravenous infusion. No untoward effects of the infused ferrocyanide were observed during or after the experiments. In nephrectomized dogs ferrocyanide reached its ultimate distribution volume 2 hrs after intravenous administration of a single dose and remained constant for up to 10 hrs. The average distribution volume was 224 +/- 17 ml-kg-1 body mass (n = 6). In intact dogs continuously infused with indicator, ferrocyanide also reached its ultimate distribution volume in 2 hrs and remained constant thereafter for up to 7 hrs after the start of the infusion. The average distribution volume was 237 +/- 27 ml-kg-1 body mass (n = 14). It is concluded that ferrocyanide fulfils the requirements to be met by an indicator for the measurement of the extracellular volume, and is well suited for repeated determinations of the extracellular fluid volume in one and the same experiment.

Animals↗
PubMedDate not supplied

Effect of high- versus low-frequency exercise training in multidisciplinary cardiac rehabilitation on health-related quality of life.

BACKGROUND: The authors examined the importance of the frequency of aerobic exercise training in multidisciplinary rehabilitation in improving health-related quality of life in the short run in patients with documented coronary artery disease. METHODS: Patients (114 males and 16 females; age range, 32-70 years) were randomized into either a high-frequency or a low-frequency exercise training program (10 versus 2 sessions per week, respectively) as part of a 6-week multidisciplinary cardiac rehabilitation program. The General Health Questionnaire and the RAND-36 were used to assess changes in psychological distress and subjective health status. RESULTS: After 6 weeks, high-frequency patients reported significantly more positive, change in "psychological distress" (P < 0.05), "mental health" (P = 0.05), and "health change" (P < 0.01), than low-frequency patients. Apart from changes in mean scores, individual effect sizes indicated that a significantly greater percentage of high-frequency patients experienced substantial improvements in "psychological distress" (P < 0.01), "physical functioning" (P < 0.05), and "health change" (P < 0.05), compared with low-frequency patients. In addition, deterioration of quality of life was observed in a considerable number of high-frequency patients (ranging from 1.7% to 25.8% on the various measures). CONCLUSIONS: The frequency of aerobic exercise has a positive, independent effect on psychological outcomes after cardiac rehabilitation. However, this benefit after high-frequency rehabilitation appears to be limited to a subgroup of patients. Further investigation is required to identify these patients. Results provide input into recent controversies regarding the role of exercise training in cardiac rehabilitation.

Adult↗