Biomedical subjects

N Dhupa

Publications and source records attributed to N Dhupa.

3 recordsLinked to original sources

PubMed1999

Airway reactivity measured by barometric whole-body plethysmography in healthy cats.

OBJECTIVE: To assess the validity of barometric whole-body plethysmography (BWBP) as a means of monitoring airway responses to induced bronchoconstriction in healthy cats. ANIMALS: 8 healthy cats without history of bronchopulmonary disease or exposure to indoor tobacco smoke. PROCEDURE: Cats were placed into a barometric plethysmograph with an internal volume of 38 L, and air flow was recorded at baseline and after carbachol (concentrations 0.005, 0.01, 0.02, 0.05, 0.1, and 0.2%) was introduced into the chamber. A dose-response curve was generated for several flow-derived measurements, and airway reactivity was determined by interpolation of the dose-response curve for enhanced pause. RESULTS: Peak inspiratory and expiratory flows increased significantly, but respiratory rate, inspiratory and expiratory times, relaxation time, and tidal volume did not differ significantly from baseline values. Flow-derived measurements (pause, enhanced pause, and end-expiratory pause) increased significantly at carbachol concentrations > 0.02%. Baseline measurements did not correlate with indices of airway reactivity. CONCLUSIONS AND CLINICAL RELEVANCE: Airway reactivity can be measured by use of BWBP, which is noninvasive. Airway reactivity was highly variable among cats and was not a function of baseline airway caliber, suggesting that other intrinsic mechanisms may be important.

Animals↗

PubMed1998

Hypocalcemia and hypomagnesemia.

The occurrence of hypocalcemia is well documented in clinical veterinary medicine. In this article, we have attempted to provide an overview of the established causes as well as information on more recently recognized etiologies such as the ionized hypocalcemia seen in cats with urethral obstruction and the presence of the disorder in critically ill patient populations. Hypomagnesemia has been identified as the most common electrolyte abnormality in canine and feline critically ill patients. Magnesium depletion and experience with supplementation appear to have most significance in diabetic ketoacidotic patients with the development of associated refractory hypokalemia. (N. Dhupa, BVM, MRCVS, unpublished observations, 1997). Although cardiac arrythmias are associated with hypomagnesemia in human patients, documentation of this association in veterinary patients is lacking. Because hypomagnesemia has been associated with other electrolyte abnormalities in human and veterinary populations, the detection of hypokalemia (particularly if refractory to therapy), hyponatremia, hypophosphatemia, or hypocalcemia should indicate the possibility of coexisting hypomagnesemia.

Animals↗

PubMed1997

Use of jugular venous blood, compared with mixed venous blood, for measurement of venous oxygenation indices in a porcine model of endotoxic shock.

OBJECTIVE: To evaluate the reliability of oxygen saturation and oxygen content values measured from jugular venous blood in estimating values measured from mixed venous blood during endotoxic shock. ANIMALS: 14 random-bred 10- to 15-kg Yorkshire pigs. PROCEDURE: 60 pairs of heparinized blood samples were simultaneously collected from the pulmonary artery and right jugular vein during an independent study, using a porcine model of endotoxic shock. Endotoxic shock was induced by infusion of Escherichia coli endotoxin. Eighteen of the sample pairs were obtained from pigs prior to infusion of endotoxin or from control pigs. Oxygen saturation and venous oxygen content were measured by direct oximetry. Analysis of bias and precision was used to compare jugular venous blood values with values obtained from mixed venous blood. Samples from endotoxemic pigs were subclassified on the basis of abnormal states of global oxygen imbalance associated with septic shock. RESULTS: Indices of venous oxygenation measured from jugular venous blood were an imprecise method of estimating values measured from mixed venous blood. There was no significant difference in bias between nonendotoxemic and endotoxemic pigs, regardless of abnormal hemodynamic states. CONCLUSION: Jugular venous blood oxygen saturation and oxygen content values should not be used to assess global oxygen transport during endotoxic shock.

Analysis of Variance↗