Assessment of Drug-Drug Interactions among Renal Failure Patients of Nephrology Ward in a South Indian Tertiary Care Hospital.

Polypharmacy is common in drug prescriptions of chronic kidney disease patients. A study of the prescription patterns of drugs with potential interactions would be of interest to prevent drug related adverse events. A prospective observational study of six months (Dec 2009-May 2010) was carried out among the chronic kidney disease patients admitted to the nephrology ward of a South Indian tertiary care hospital. The pattern and rates of drug-drug interactions seen in the prescriptions of these patients was studied. Among the 205 prescriptions included, a total of 474 interactions were reported, making 2.7 interactions per prescription with incidence rates of 76.09%. Around 19.62% of interactions were of major severity. Most common interactions were found between ascorbic acid and cyanocobalamine (12.45%), clonidine and metoprolol (3.80%) respectively. Hypo or hypertension (31.65%), decreased drug efficacy (29.11%) and hypo or hyperglycemia (14.14%), were the most commonly reported clinical outcomes of the drug interactions. Cardiovascular drugs (calcium channel blockers and beta blockers; 52%) constitute the major class of drugs involved in interactions. As most of the interactions had a delayed onset, long term follow-up is essential to predict the clinically significant outcomes of these interactions. Hence, drug interactions are commonly seen in the prescriptions of chronic kidney disease patients which can lead to serious adverse events if not detected early. Need for collaboration with a clinical pharmacist and electronic surveillance, which are absent in developing countries like India, is emphatic.

Framework for estimating tumour parameters using thermal imaging.

BACKGROUND & OBJECTIVES: Non-invasive and non-ionizing medical imaging techniques are safe as these can be repeatedly used on as individual and are applicable across all age groups. Breast thermography is a non-invasive and non-ionizing medical imaging that can be potentially used in breast cancer detection and diagnosis. In this study, we used breast thermography to estimate the tumour contour from the breast skin surface temperature. METHODS: We proposed a framework called infrared thermography based image construction (ITBIC) to estimate tumour parameters such as size and depth from cancerous breast skin surface temperature data. Markov Chain Monte Carlo method was used to enhance the accuracy of estimation in order to reflect clearly realistic situation. RESULTS: We validated our method experimentally using Watermelon and Agar models. For the Watermelon experiment error in estimation of size and depth parameters was 1.5 and 3.8 per cent respectively. For the Agar model it was 0 and 8 per cent respectively. Further, thermal breast screening was done on female volunteers and compared it with the magnetic resonance imaging. The results were positive and encouraging. INTERPRETATION & CONCLUSIONS: ITBIC is computationally fast thermal imaging system and is perhaps affordable. Such a system will be useful for doctors or radiologists for breast cancer diagnosis.

Improved infrared thermography based image construction for biomedical applications using Markov Chain Monte Carlo method.

Breast thermography is one of the scanning techniques used for breast cancer detection. Looking at breast thermal image it is difficult to interpret parameters or tumor such as depth, size and location which are useful for diagnosis and treatment of breast cancer. In our previous work (ITBIC) we proposed a framework for estimation of tumor size using clever algorithms and the radiative heat transfer model. In this paper, we expand it to incorporate the more realistic Pennes bio-heat transfer model and Markov Chain Monte Carlo (MCMC) method, and analyze it's performance in terms of computational speed, accuracy, robustness against noisy inputs, ability to make use of prior information and ability to estimate multiple parameters simultaneously. We discuss the influence of various parameters used in its implementation. We apply this method on clinical data and extract reliable results for the first time using breast thermography.

Potassium homeostasis during & after cardiopulmonary bypass.

Potassium homeostasis was studied in 30 patients undergoing cardiac surgery by employing cardiopulmonary bypass (CPB) and moderate hypothermia, and using morphine, N2O, relaxant anaesthesia. There was a trend for hypokalemia, and for maintaining a K+ level of 4-4.5 mmol/l, K+ infusion was required during CPB (9.017 mmol/m2 BSA/h). K+ infusion required in the post-operative period was considerably less (1.532 mmol/m2 BSA/h). There was no significant difference in the K+ levels of patients receiving preoperative diuretic therapy, as compared to those not receiving such therapy. Potassium requirement was significantly higher in patients under-going CABG and valvular heart disease, as compared to congenital heart disease. The mean urinary loss of K+ during bypass was found to be 2.95 mmol/m2 BSA/h, which was only 32 per cent of that required to be infused (9.017 mmol/m2 BSA/h). The mean excretion of K+ in the post operative period was significantly higher (4.53 mmol/m2 BSA/h) than K+ required to be infused during this period (1.532 mmol/m2 BSA/h).

Preparation and evaluation of 99mTc-t-butylisonitrile (99mTc-TBI) for myocardial imaging: a kit for hospital radiopharmacy.

A previous method was modified to obtain [99mTc(TBI)6]+ by reacting Zn(TBI)2Br2 directly with 99mTcO4- in the presence of Sn2+ ions. [Cu(TBI)4]Cl was next used as a source of TBI. On reaction with 99mTcO4- and Sn2+ ions for 3 min at 100 degrees C, [99mTc(TBI)6]+ product of radiochemical purity greater than 90% and yield greater than 70% was obtained. Data of biodistribution in rats (2-2.5% in heart) and biokinetics in rabbits were satisfactory. The kit formulation was found to be stable and also safe for administration.