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V S Mathur

Publications and source records attributed to V S Mathur.

At least 19 recordsLinked to original sources
PubMed2005

Assessing prescription writing skills of pre-clerkship medical students in a problem-based learning curriculum.

OBJECTIVE: To audit the acquisition of prescribing skills of pre-clerkship medical students in a problem-based learning (PBL) curriculum that incorporates a prescribing program. MATERIAL AND METHODS: Student performance in pharmacotherapy stations included in six out of eight end-of-unit-objective structured practical examinations (OSPE) was evaluated using a rating checklist. RESULTS: Prescription writing skills of 539 students (66.2% female and 33.8% male) were appraised. With the exception of refill element, the other physician-related components including prescriber's identity, date of prescription order, patient's identity, the symbol Rx "Take Thou", and prescriber's signature were written by 96.1% of the students (95% confidence interval (CI) 94.1 - 97.5). However, the drug-related components such as the appropriateness of drug(s) selected, strength, dosage form, quantity to be dispensed and directions for use were written satisfactorily by 50.2% of the students (95% CI 46.0 - 54.4). With respect to prescribing skills, the mean total score of Year 4 students did not significantly differ from that of Year 2 (69.4 (CI 65.7 - 73.1) vs. 66.3 (CI 62.7 to 69.9); p = 0.237). However, the mean scores of individual drug-related components such as appropriateness of drug(s) selected, dosage form, and direction for use were significantly higher in Year 4 than that of Year 2 students (p < 0.05). Of 381 rationally prescribed drugs, 81.1% were written with generic names. CONCLUSION: This study revealed that the students acquire prescribing skills to a limited extent during the pre-clerkship phase in a PBL program. Prescribing errors and deficits were found to be mainly associated with drug-related components. Further training and assessment of prescribing skills during the clerkship and internship period are needed to achieve mastery of this skill as a terminal competency of graduating physicians.

Bahrain↗
PubMed2003

Trends in ophthalmic antimicrobial utilization pattern in Bahrain between 1993 and 2000: a resurgence of chloramphenicol?

OBJECTIVES: The occurrence of aplastic anemia following topical administration of ophthalmic chloramphenicol is controversial and debated internationally. We have determined the influence of such debate on the utilization of ophthalmic chloramphenicol in Bahrain, through studying the utilization patterns of ophthalmic antimicrobial preparations by the Ministry of Health, with an emphasis on chloramphenicol, between 1993 and 2000. Cost-implications of these patterns are examined. MATERIAL AND METHODS: Information on the annual purchase of ophthalmic antimicrobial drug preparations and their unit price was obtained from the Directorate of Materials Management, Ministry of Health, and analyzed. RESULTS: In 1993, the 3 most commonly purchased ophthalmic antibacterial preparations were oxytetracycline 1% eye ointment (40.1%); sulfacetamide 10% and 20% eye drops (25.3%); and chloramphenicol 0.5% eye drops and 1% eye ointment (10.8%). In 2000, oxytetracycline remained the most frequently purchased preparation (33%), followed by chloramphenicol (21.2%). Between 1993 and 1999, chloramphenicol purchases fluctuated between 10% to 16.4% with a remarkable increase to 21.2%, in 2000. Chloramphenicol accounted for 8.6% and 15.1% of cost of total ophthalmic preparations purchased in 1993 and 2000, respectively. CONCLUSION: Despite continued concerns of potential risks of ophthalmic chloramphenicol, this preparation is extensively utilized in Bahrain. We are of the opinion that for minor infections, chloramphenicol ophthalmic preparations should be replaced by safer alternatives. Further, we recommend that their use be reserved for ocular infections that are resistant to other antimicrobials, and that ophthalmologists, at the secondary care level, should supervise such treatment.

Administration, Topical↗
PubMed2002

Fenoldopam mesylate blocks reductions in renal plasma flow after radiocontrast dye infusion: a pilot trial in the prevention of contrast nephropathy.

BACKGROUND: Radiocontrast nephropathy (RCN) is a common source of acute renal failure in hospitalized patients and is associated with increased morbidity and mortality rates. Fenoldopam mesylate is a dopamine A1 receptor agonist that augments renal plasma flow (RPF) in patients with normotensive and hypertensive conditions. To determine whether fenoldopam mesylate attenuates reductions in RPF after contrast infusion, we conducted a double-blind, randomized, placebo-controlled pilot trial of fenoldopam mesylate in patients who underwent contrast angiography. METHODS: Fifty-one patients with chronic renal insufficiency (creatinine level, 2.0-5.0 mg/dL) who were undergoing contrast angiography were screened, and 45 patients were randomized to receive normal saline solution (1/2 NS) or 1/2 NS plus fenoldopam mesylate at 0.1 microg/kg/min at lease 1 hour before infusion with contrast dye. Serum creatinine level was measured at baseline and at 24, 48, and 72 hours after angiography. The primary endpoint was change in RPF 1 hour after contrast infusion. The secondary endpoint was incidence of RCN, defined as a 0.5 mg/dL or a 25% rise in serum creatinine level at 48 hours. RESULTS: RPF at 1 hour after angiography was 15.8% above baseline in the fenoldopam mesylate group compared with 33.2% below baseline in the 1/2 NS group (P <.05). The incidence rate of RCN at 48 hours was 41.0% in the 1/2 NS group versus 21% in the fenoldopam mesylate group (P =.148). Among patients with diabetes, the incidence rate of RCN tended to be higher in the 1/2 NS group compared with the fenoldopam mesylate group (64% vs 33%; P =.14). The peak serum creatinine level at 72 hours after contrast infusion was significantly higher at in the 1/2 NS group (creatinine level, 3.6 +/- 1.0 mg/dL) compared with the fenoldopam mesylate group (creatinine level, 2.8 +/- 0.35 mg/dL; P <.05). RPF was significantly (P <.0001) reduced in patients with RCN compared with patients in whom RCN did not develop. CONCLUSION: The results of this pilot trial suggest that fenoldopam mesylate is a promising prophylactic agent for RCN and that larger multicenter trials should be conducted to prove its efficacy.

Acute Kidney Injury↗
PubMed2001

Recruitable patency of the internal mammary artery graft.

A 46-year-old man underwent two coronary bypass operations and three percutaneous interventions over a period of 18 years. A non-functioning internal mammary artery (IMA) graft, was observed shortly after the second surgery. This graft was anastomosed to the left anterior descending (LAD) that had adequate flow from an older vein graft placed during the first surgery. Over the ensuing 8 years, the IMA graft regained patency after progressive occlusive disease in the competing vein graft.

Angioplasty, Balloon, Coronary↗
PubMed2001

Antihypertensive drug prescription trends at the primary health care centres in Bahrain.

PURPOSE: To determine the antihypertensive drug prescribing pattern by primary care physicians in patients with uncomplicated essential hypertension; to identify whether such pattern of prescription is appropriate and in accordance with international guidelines for pharmacotherapy of hypertension; and to estimate the impact of such prescriptions on cost of treatment. METHODS: A prescription-based survey among patients with uncomplicated essential hypertension was conducted in seven out of a total of 18 health centres in Bahrain. The relevant data for our study was collected using cards, designed for chronically-ill patients. RESULTS: A total of 1019 male and 1395 female (62.9%) out of 3838 of the study population were on monotherapy, whereas 596 male and 828 female (37.1%) were on antihypertensive combination therapy. Among the monotherapy category, the various antihypertensive drugs used were as follows: beta-blockers (58.8%), angiotensin converting enzyme (ACE) inhibitors (14.2%), calcium channel blockers (11.1%), diuretics (8.1%) and alpha-methyldopa (7.0%). With respect to overall utilization pattern, beta-blockers were the most frequently prescribed (65.5%), diuretics ranked second (27.4%), followed by ACE inhibitors (20.6%), calcium channel blockers (19.9%) and alpha-methyldopa (8.5%). Within each class of antihypertensives used, the most frequently used individual agents were as follows: (a) among beta-blockers 97.7% used atenolol; (b) among the diuretics, indapamide (35.4%), hydrochlorothiazide (HCTZ) (32.7%), HCTZ in combination with triamterene (25.7%), and chlorthalidone (4.6%); (c) among the ACE inhibitors, captopril (44.9%), enalapril (29.7%), and lisinopril (19.0%); (d) among the calcium channel blockers, nifedipine (98.2%). Significant age- and gender-related differences in prescribing patterns were seen. Short-acting nifedipine monotherapy was inappropriately prescribed in a significant number of patients above the age of 50 years. ACE inhibitors accounted for approximately two-thirds of the total antihypertensive drug expenditure, although these drugs represent only one-fifth of overall antihypertensives used. There is a trend towards excessive use of expensive thiazide-like diuretics such as indapamide which seems to be unjustifiable practice, particularly in a study population free from diabetic hypertensive patients. CONCLUSIONS: The general pattern of antihypertensive utilization appears to be in accordance with the guidelines of WHO and the Joint National Committee issued in the 1990s. The trends of prescribing of antihypertensives were in favour of conventional ones such as the beta blockers and diuretics, and the introduction of newer classes of antihypertensives had a generally minimal impact on the prescribing profile. Almost two-thirds of the patients were treated with monotherapy. A disproportionately large percentage of antihypertensive drug cost was due to overt use of ACE inhibitors, and indapamide, instead of thiazide diuretics. The use of short-acting calcium channel blockers especially in the elderly is unjustifiable.

Adolescent↗
PubMed2001

Rational pharmacotherapy of hypertension in the elderly: analysis of the choice and dosage of drugs.

OBJECTIVES: To determine in older people with uncomplicated hypertension: (a) the pattern of prescribing of antihypertensives; (b) the extent of physicians' adherence to recommendations on dosage for antihypertensive combinations; (c) whether prescribing practice conforms with recommended therapeutic guidelines; and (d) the frequency of prescribing of other drugs which have the potential to alter the efficacy of antihypertensive agents. METHODS: A survey of prescribing in older patients with uncomplicated hypertension in primary care setting of Bahrain was conducted. RESULTS: Of the 432 (56.5%) patients on monotherapy, 192 (44.4%) were treated with beta-blockers, 87 (20.1%) with calcium channel blockers (CCBs), 53 (12.3%) with alpha-methyldopa, 47 (10.9%) with diuretics, 46 (10.6%) with angiotensin converting enzyme (ACE) inhibitors, and 7 (1.6%) with hydralazine. Of the 1146 patients on mono- or combination therapies, 434 (56.8%) were treated with beta-blockers, 244 (31.9%) with diuretics, 211 (27.6%) with CCBs, 139 (18.2%) with ACE inhibitors, 103 (13.5%) with alpha-methyldopa 8 (1.0%) with brinerdine and 7 (0.9%) with hydralazine. In the 332 (43.5%) patients on combination therapy, 15 different two- and three-antihypertensive drug combinations were prescribed: a diuretic with a beta-blocker (37.2%) and a beta-blocker with either a CCB (20.9%) or an ACE inhibitor (12.4%) were the most popular two-drug regimens. The most commonly prescribed triple drug regimens were a diuretic and a beta-blocker plus either a CCB (26.1%) or an ACE inhibitor (17.4%) and diuretic plus an ACE inhibitor and a CCB (15.2%). Daily dosage of beta-blockers, ACE inhibitors and alpha-methyldopa were somewhat high in a considerable proportion of patients on both mono- and combined therapies. A substantial proportion (9.7%) of patients on monotherapy were treated with immediate release nifedipine. CONCLUSION: The pharmacotherapy of hypertension in elderly patients was found in some instances not to conform to recommended guidelines. For certain classes of antihypertensive agent such as beta-blockers, ACE inhibitors and alpha-methyldopa, neither the principles of geriatric pharmacology nor of antihypertensive combination therapy, and in particular, the need to reduce daily dosage, were followed. The use of immediate release nifedipine in the elderly is irrational, and instead, the use of long-acting dihydropyridine CCBs should be considered. The results of long-term randomized clinical trials published during the last decade have had a minimal impact on clinical practice of primary care physicians in Bahrain.

Aged↗
PubMed2001

Prescribing patterns and therapeutic implications for diabetic hypertension in Bahrain.

OBJECTIVE: To determine drug prescription patterns and the extent of conformity with World Health Organization/international Society of Hypertension (WHO/ISH) guidelines in diabetic hypertension. DESIGN: Retrospective prescription-based survey. SETTING: Seven primary-care health centers, comprising approximately one-third of primary-care health centers in Bahrain. PATIENTS: Patients with type 2 diabetes and hypertension. MAIN OUTCOME MEASURE: The prescribing pattern of antihypertensive and antidiabetic drugs. RESULTS: Among a study sample of 1,463 patients with type 2 diabetes and hypertension, antidiabetic agents were prescribed as monotherapy in the following descending order: glyburide, gliclazide, insulin, and metformin. As combinations, sulfonylureas plus metformin was most popular, followed by metformin plus insulin, and sulfonylureas plus insulin. Sulfonylurea and metformin with insulin was rarely used. There was no significant difference in prescribing of glyburide and metformin between the elderly and young middle-aged diabetic patients; many patients older than 65 years were treated with a beta-blocker along with a long-acting sulfonylurea. Both as monotherapy and in overall use, beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, and calcium-channel blockers were most often prescribed. Among 35.5% patients treated with antihypertensive combinations, various two- and three-drug combinations of beta-blockers, ACE inhibitors, calcium-channel blockers, and diuretics were often used. The proportion of patients taking atenolol 100 mg/d was higher with combination regimens. Hydrochlorothiazide 25 mg or equivalent thiazide diuretics were extensively used. CONCLUSIONS: The prescribing pattern of antihypertensives in diabetic hypertension differs in many instances from WHO/ISH guidelines, especially regarding the choice of antihypertensive drugs and their combinations. The appropriateness of antidiabetic drug choice is questionable in relation to the antihypertensive used.

Adrenergic beta-Antagonists↗
PubMed2001

Pathophysiology of radiocontrast nephropathy and use of fenoldopam for its prevention.

There are no proven therapeutic agents for the prevention or treatment of acute renal failure. Radiocontrast agents induce intense vasoconstriction in the renal medulla, which is hypoxic even in normal physiologic states, thereby aggravating the imbalance of medullary oxygen supply and demand. Fenoldopam specifically increases blood flow to the renal medulla through selective agonism of dopamine-1 receptors and has been found to prevent radiocontrast nephropathy in several investigations, including one randomized, double-blind, placebo-controlled trial.

Acute Kidney Injury↗
PubMed2001

Design and rationale of CONTRAST--a prospective, randomized, placebo-controlled trial of fenoldopam mesylate for the prevention of radiocontrast nephropathy.

Radiocontrast-induced nephropathy develops in approximately 10% to 20% of patients following administration of iodine-based dye and is one of the most prognostically detrimental complications that invasive cardiologists and radiologists encounter. Preexisting renal dysfunction and diabetes mellitus are two of the most powerful predictors of the likelihood of developing acute renal insufficiency after contrast delivery. To date, only adequate preprocedural hydration and postprocedural hydration to offset dehydration from contrast-induced diuresis have been shown to be effective in preventing this condition. Fenoldopam mesylate, a systemic vasodilator currently FDA-approved for short-term, in-hospital management of severe hypertension, has been shown to increase renal plasma flow in patients with and without chronic renal insufficiency. As a selective agonist of the dopamine-1 receptor, fenoldopam may preserve outer medullary renal blood flow and thereby attenuate radiocontrast-induced nephropathy. Small studies with fenoldopam prior to iodine-based dye administration have demonstrated low rates of radiocontrast nephropathy, and a larger, randomized trial has found that renal blood flow 1 hour after angiography rose in the fenoldopam group compared to a decline in the placebo group. The CONTRAST study has been designed to determine whether fenoldopam is indeed effective in diminishing the occurrence of radiocontrast-induced nephropathy.

Acute Kidney Injury↗
PubMed2000

Patterns of utilization of antihypertensive drug combinations in Bahrain: do they conform with international guidelines?

OBJECTIVES: To explore the prescribing pattern and rationale of antihypertensive combination drug therapy at the level of primary health care centers; and to analyze the extent of physicians' adherence to dosage range of antihypertensives in combination regimens as recommended by Guidelines Subcommittee of WHO/ISH 1999. SUBJECTS, MATERIAL AND METHODS: A prescribing survey of antihypertensive combination regimens among patients with uncomplicated essential hypertension was conducted in 7 out of a total of 18 health centers in Bahrain. The relevant data for our study was collected using cards designed for chronically ill patients. RESULTS: A total of 2414 hypertensive patients (62.9%), of a 3838 study population, were on monotherapy, whereas 1414 (37.1%) were on antihypertensive combination therapy. Among those who were treated with drug combinations, 85.1% (n = 1212) received two-drug, 14.2% (n = 202) received three-drug and four- and five-drug regimens were used by 0.6% and 0.07%, respectively. Prescription analysis revealed that 17 different two- and three-antihypertensive drug combinations were prescribed for each category. The four major two-drug regimens were ranked in the following order: a beta-blocker with a diuretic (40.4%) used more frequently in females than in males (p < 0.0001), a beta-blocker with a calcium channel blocker (19.7%), a beta-blocker with an ACE inhibitor (12.8%) and a diuretic with an ACE inhibitor (7.3%) - used more frequently in males than in females (p = 0.001, 0.01, and 0.028, respectively). The most frequently prescribed three-drug regimens were diuretic and a beta-blocker plus either an ACE inhibitor (30.7%) or a calcium channel blocker (22.3%), beta-blocker plus an ACE inhibitor and a calcium channel blocker (16.3%), and a diuretic plus an ACE inhibitor and a calcium channel blocker (11.4%). There was no gender-related difference among triple-drug regimens. There was a trend towards using high doses of the beta-blocker atenolol, ACE inhibitors and methyldopa. CONCLUSION: The prescribing patterns of some practising physicians were analyzed in terms of conformity with guidelines of combination of drugs and dosages. The use of antihypertensive combination therapy and the doses of individual drugs in combination regimens seem to be partly non-compliant with guidelines issued by WHO recommendations; this is illustrated by excessive prescription of some irrational combinations, as well as limited prescription of some rational combinations. In addition, a tendency to use high doses of certain classes of antihypertensive combinations was observed.

Antihypertensive Agents↗
PubMed2000

The string phenomenon: an important cause of internal mammary artery graft failure.

Internal mammary arteries are the grafts of choice for coronary artery bypass because they are generally free of atherosclerosis and they have high patency rates as grafts. There are, however, increasing reports of graft failure due to diffuse or distal narrowing, known as the string phenomenon. From June 1999 to October 1999, we prospectively reviewed all cases of internal mammary artery angiography at our institution. Twenty-eight cases of internal mammary artery graft failure were identified (M:F, 15:13; mean age, 62 years) out of 261 patients who had undergone internal mammary artery grafting at any institution, including ours. The mean interval between coronary artery bypass and re-angiography was 35 months. There was evidence of competitive flow in 81% (22 of 27) of patients whose internal mammary grafts had developed the string sign. This observational study supports the hypothesis that competitive flow predisposes internal mammary grafts to the string phenomenon. Given the high frequency of competitive flow situations amongst patients with internal mammary artery graft failure, caution should be exercised in the anastomosis of the internal mammary artery to recipient vessels that are less than severely stenosed.

Cineangiography↗
PubMed1999

The effects of fenoldopam, a selective dopamine receptor agonist, on systemic and renal hemodynamics in normotensive subjects.

OBJECTIVE: Acute renal failure, frequently a consequence of renal vasoconstriction and subsequent renal ischemia, is a common problem for which no proven preventive or therapeutic agents exist. Fenoldopam is a new, selective, dopamine-1 receptor agonist that causes both systemic and renal arteriolar vasodilation. In hypertensive patients, fenoldopam rapidly decreases blood pressure, increases renal blood flow, and maintains or improves the glomerular filtration rate. We sought to determine a dose of fenoldopam that increases renal blood flow without inducing hypotension in normotensive patients and to explore the role of volume status (sodium replete vs. deplete) in these effects. DESIGN: Randomized, double-blind, placebo-controlled, cross-over study. SETTING: Clinical research unit. PATIENTS: Fourteen normal male volunteers. INTERVENTIONS: Renal plasma flow (para-aminohippurate clearance) and glomerular filtration rate (inulin clearance) were measured during three fixed, escalating doses of fenoldopam (0.03, 0.1, and 0.3 Lg/kg/min) on both a high-sodium and a low-sodium diet. MEASUREMENTS AND MAIN RESULTS: Fenoldopam significantly increased renal plasma flow in a dose-dependent manner compared with placebo: 670 + 148 vs. 576 + 85 mUmin at 0.03 iLg/kg/min; 777 + 172 vs. 579 + 80 mUmin at 0.1 tig/kg/min; and 784 + 170 vs. 592 + 165 mUmin at 0.3 ilg/kg/min (p < .05 fenoldopam vs. placebo at all three doses). Glomerular filtration rate was maintained. At the lowest dose (i.e., 0.03 ILg/kg/min), significant renal blood flow increases occurred without changes in systemic blood pressure or heart rate. At 0.1 and 0.3 Lgl/kg/ min, systolic blood pressure did not change, but diastolic blood pressure was slightly lower in the fenoldopam group than in the placebo group: 62.5 + 6.4 vs. 63.6 + 2.6 mm Hg, respectively, at 0.3 tg/kg/min (p < .05). None of the effects of fenoldopam were altered by volume status. CONCLUSIONS: Fenoldopam increased renal blood flow in a dose-dependent manner compared with placebo, and, at the lowest dose, significantly increased renal blood flow occurred without changes in systemic blood pressure or heart rate. These findings will be useful in designing future studies exploring the role of fenoldopam in preventing or treating renal failure in patients who are not hypertensive.

Acute Kidney Injury↗
PubMed1998

Acute renal allograft dysfunction secondary to suprarenal arterial stenosis: a case series and review of the literature.

Stenosis of vessels proximal to the renal artery is an unusual cause of allograft ischemia. We report four patients who had such 'suprarenal' arterial stenoses leading to graft dysfunction that was reversed with revascularization. We additionally review the existing literature on this entity, outline the etiologies of such stenoses, as well as discuss the surgical and non-surgical therapeutic options in patients with this uncommon cause of allograft dysfunction.

Acute Disease↗
PubMed1997

Polyomavirus-induced interstitial nephritis in two renal transplant recipients: case reports and review of the literature.

We present two case reports of renal polyomavirus infection leading to renal allograft dysfunction, review the literature of this entity, and discuss the role of specific immunosupressives. Histologically, the virus caused an interstitial infiltrate composed of plasma cells and lymphocytes, interstitial fibrosis, and tubular atrophy. Viral inclusions were seen within tubular cells on light microscopy. Electron microscopy showed viral particles of 40 to 50 nm in a characteristic paracrystalline array. Both patients had been on FK-506-based immunosuppression. In both patients, the virus appeared to clear histologically and renal function stabilized when the patients were converted to cyclosporine-based immunosuppression. Contrary to prior reports, our patients have not lost their grafts and continue to have stable, albeit reduced, graft function at 2.5 years and 4.5 years following the initial diagnosis of renal polyomavirus infection.

Acute Disease↗
PubMed1997

Low-molecular-weight heparin and abciximab for thrombo-occlusive saphenous vein graft disease. Report of 2 cases.

Both reoperation and alternative treatments for thrombo-occlusive disease of saphenous vein grafts have been fraught with a high rate of complications and a low rate of long-term success. We report 2 cases in which thrombo-occlusive saphenous vein graft disease was treated with the aid of abciximab during the intervention and with low-molecular-weight heparin for 7 to 12 days in an outpatient setting.

Abciximab↗
PubMed1988

Coronary artery anomalies: a review of more than 10,000 patients from the Clayton Cardiovascular Laboratories.

We reviewed the records of 10,661 patients who had undergone coronary angiography at the Clayton Foundation Cardiovascular Laboratories between 1 June 1974 and 15 March 1986, and identified major coronary artery anomalies in 83 adults. In addition, we included in our review 9 adults and 2 adolescents who had been referred for evaluation of anomalies documented elsewhere. Here we present the clinical and angiographic data for all 94 patients (76 men and 18 women). Most patients were men who presented with chest pain. The most common anomaly, found in 38 patients, was origin of left circumflex coronary artery from right coronary artery or right aortic sinus. In contrast to other studies, which have not shown increased incidence of coronary atherosclerosis in the anomalous circumflex artery, 71% of our patients with this anomaly had significant coronary atherosclerosis in the proximal portion of the anomalous vessel. The posterior course of the anomalous circumflex coronary artery may predispose this vessel to atherosclerosis in patients with coronary disease. The overall incidence of atherosclerotic disease in coronary arteries was 68% (64 of 94 patients) in the present study.

Journal Article↗