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J Parameshwar

Publications and source records attributed to J Parameshwar.

At least 19 recordsLinked to original sources
PubMed2003

Atrial septostomy in the treatment of severe pulmonary arterial hypertension.

BACKGROUND: Atrial septostomy (AS) may improve symptoms and haemodynamics in patients with severe pulmonary arterial hypertension (PAH). METHODS: Twenty AS performed in 17 patients with severe progressive PAH (13 primary pulmonary hypertension, two collagen vascular disease, one thromboembolic disease, one vaso-occlusive disease) were analysed. Seven patients were in NYHA class III and 10 in NYHA IV. Fifteen patients were on long term prostanoid treatment. AS was performed under fluoroscopy using graded balloon technique. RESULTS: AS improved clinical symptoms and increased the cardiac index from 1.8 to 2.2 l/min/m(2) and systemic oxygen transport from 263.2 to 329.6 ml/min/m(2) (p<0.001). Procedure related complications included one non-fatal atrial puncture and one unsuccessful septal puncture. Four patients died within 1 week of surgery from uncontrolled tachyarrhythmia (n=1), severe hypoxaemia (n=1), and multiorgan failure (n=2). One further patient died after voluntarily discontinuing renal dialysis. Twelve patients are alive 5-17 months after the operation with five patients undergoing heart-lung transplantation. There were no differences in haemodynamic and functional parameters between the non-survivors and the mid term survivors. However, the non-survivors were significantly older (52 v 36 years, p<0.01) and had a significantly lower creatinine clearance rate (70 ml/min v 48 ml/min, p<0.05). CONCLUSION: Atrial septostomy improves clinical symptoms, cardiac index, and systemic oxygen transport and has the potential to influence the prognosis in selected cases of severe PAH.

Adolescent↗
PubMed2001

Improved outcome with organs from carbon monoxide poisoned donors for intrathoracic transplantation.

BACKGROUND: The success of intrathoracic organ transplantation has lead to a growing imbalance between the demand and supply of donor organs. Accordingly, there has been an expansion in the use of organs from nonconventional donors such as those who died from carbon monoxide poisoning. We describe our experience with 7 patients who were transplanted using organs after fatal carbon monoxide poisoning. METHODS: A retrospective study of the 1,312 intrathoracic organ transplants between January 1979 and February 2000 was completed. Seven of these transplants (0.5%) were fulfilled with organs retrieved from donors after fatal carbon monoxide poisoning. There were six heart transplants and one single lung transplant. The history of carbon monoxide inhalation was obtained in all of these donors. RESULTS: Five of 6 patients with heart transplant are alive and well with survival ranging from 68 to 1,879 days (mean, 969 +/- 823 days). One patient (a 29-year-old male) died 12 hours posttransplant caused by donor organ failure. The patient who had a right single lung transplant did well initially after the transplant, but died after 8 months caused by Pneumocystis carinii pneumonia. All those recipients who were transplanted from carbon monoxide poisoned donors and ventilated for more than 36 hours, survived for more than 30 days. Moreover, these donors were assessed and optimized by the Papworth donor management protocol. CONCLUSIONS: Carbon monoxide poisoned organs can be considered for intrathoracic transplantation. In view of the significant risk of donor organ failure, a cautious approach is still warranted. Ideally, the donor should be hemodynamically stable for at least 36 hours from the time of poisoning and on minimal support. A formal approach of invasive monitoring and active management further improves the chances of successful outcome.

Adult↗
PubMed2000

Randomized trial of blood eosinophil count monitoring as a guide to corticosteroid dosage adjustment after heart transplantation.

BACKGROUND: Increases in blood eosinophil counts (EOS) beyond 0.06 x 10(9)/liter precede treated heart allograft rejection. An oral prednisolone dose of 0.35 mg/kg/day usually suppresses EOS below this threshold. METHODS: We designed a randomized trial to compare our empirical protocol for steroid dose adjustment with a novel protocol guided by EOS monitoring during the first 3 months after heart transplantation. Eighty patients were randomized to either have their EOS reported and used for steroid dose adjustment (RG; n=40), or not reported (NG; n=40). RG patients had their steroid dosage increased if EOS exceeded 0.06 x 10(9)/liter. RESULTS: RG patients had an 83% lower risk of treated rejection (P=0.035) and lower median intravenous dose of methyl-prednisolone (P=0.017) than NG during the first 6 postoperative weeks. The proportion of diagnostic increases in EOS that were followed within 2 weeks by treated rejection was 42% greater in NG than RG (P=0.0001), compatible with a direct impact of EOS-guided prednisolone dose adjustment on the risk of subsequent rejection. Overall, RG had less than half the risk of rejection of any grade (P<0.001) and significantly more rejection-free biopsies than NG (P=0.001). The mean oral prednisolone dosage was significantly greater in RG than NG during the first (P=0.014) and second (P=0.001) 6 weeks of follow-up. This did not increase the incidence of serious steroid-related side effects. CONCLUSIONS: EOS monitoring is a simple, cheap, and effective means of optimizing steroid immunosuppression. Restriction of the EOS-guided steroid dosing protocol to periods of prolonged hospitalisation during the first 3 postoperative months should limit the requirement for higher prednisolone dosage without affecting immunosuppressive efficacy.

Adrenal Cortex Hormones↗
PubMed1999

Intravenous ganciclovir prophylaxis for cytomegalovirus in heart, heart-lung, and lung transplant recipients.

Cytomegalovirus (CMV) disease has had a significant clinical impact on the heart, heart-lung and lung transplant recipients in our centre. CMV disease has been so severe with CMV antibody-negative heart-lung transplant patients receiving organs from CMV antibody-positive donors (CMV-mismatched patients) that in 1986 we adopted the policy of not transplanting CMV-positive organs into CMV-negative heart-lung or lung recipients. In December 1992, we instituted a policy of providing intravenous ganciclovir (5 mg/kg twice a day for 28 days) during the immediate postoperative period for CMV-mismatched heart recipients and CMV antibody-positive heart-lung and lung patients, who have been the patients at greatest risk of severe CMV disease in our centre. A placebo group was not employed because of ethical considerations, ganciclovir having been shown to be effective for the treatment of CMV infections among transplant patients. Compared with a historical control group of patients receiving no prophylaxis, prophylactic ganciclovir reduced the incidence of CMV infection (39 % vs 91 %, P = 0.0006) and CMV disease (17 % vs 74 %, P = 0.0004) among CMV antibody-positive heart-lung recipients. Prophylactic ganciclovir did not significantly reduce the incidence of CMV infection or disease among heart or isolated lung recipients. Ganciclovir was well tolerated, with few adverse reactions. In the case of heart-lung transplant patients, one month of intravenous prophylactic ganciclovir significantly reduced the incidence of both CMV infection and disease when compared with patients who received no prophylaxis. With the lung transplant and heart transplant patients, there were no significant differences between the prophylaxis and nonprophylaxis groups, although there was a consistent trend towards less infection and disease in the prophylaxis groups.

Adolescent↗
PubMed1999

A prospective randomized trial of complete atrioventricular transplantation versus ventricular transplantation with atrioplasty.

BACKGROUND: The standard technique of ventricular transplantation with atrioplasty (SOHT) distorts atrial anatomy. This may compromise diastolic ventricular function, impair atrioventricular valve competence and elevate resting ANP secretion. In contrast, complete atrioventricular anastomosis (CAVT) preserves atrial geometry. METHODS: We evaluated long term outcome in a prospective randomized trial of CAVT vs. SOHT. The primary outcome measures were peak oxygen uptake, atrioventricular valve regurgitation and ANP secretion. RESULTS: 58 recipients (median age 49 years; range 21-64) were consecutively randomized (29 CAVT; 29 SOHT). There were no differences in total ischaemic time, cardiopulmonary bypass time, postoperative bleeding or immunosuppression. Cardiopulmonary exercise tolerance testing was performed by 29 recipients at 742 to 1825 days. Pulmonary function was equivalent. Peak oxygen consumption expressed as a percentage of predicted maximum was 53.5% with CAVT and 63.8% with SOHT (p = 0.14). Echocardiography was performed on 41 recipients at 944 to 1665 days. There was less tricuspid regurgitation with CAVT (3/22 [13.6%] CAVT vs. 10/19 [52.6%] SOHT; p = 0.019). The incidence of mitral regurgitation was similar (5/22 [22.7%] CAVT vs. 4/19 [21.1%] SOHT; p = 0.803). Resting ANP secretion was assessed in 17 recipients at 1013 to 1812 days. All were hemodynamically stable and none had concurrent rejection. Resting ANP secretion was less with CAVT (CAVT: 283 pg/ml; SOHT: 521.4; p = 0.041). CONCLUSIONS: Peak oxygen consumption was not influenced by implantation technique. However, CAVT reduced the incidence of tricuspid regurgitation and attenuated the elevation in resting ANP secretion.

Adult↗
PubMed1999

Randomized, trough blood cyclosporine concentration-controlled trial to compare the pharmacodynamics of Sandimmune and Neoral in de novo lung transplant recipients.

The greater and more consistent absorption of cyclosporine from the microemulsion formulation (Neoral; Novartis Pharmaceuticals Ltd., Frimley, UK) when compared with that from the original form (Sandimmune; Novartis Pharmaceuticals Ltd., Frimley, UK) results in greater systemic exposure. Lung transplant recipients could particularly benefit from this enhanced exposure, but not at the expense of excessive cyclosporine toxicity. We compared the pharmacodynamics of Neoral and Sandimmune over the first postoperative year in 50 lung transplant recipients. Twenty-eight patients were randomly selected to receive Neoral and 22 to receive Sandimmune. Nine patients with cystic fibrosis (CF) were randomly selected independently (5, Neoral; 4, Sandimmune). Patients were maintained on similar trough blood cyclosporine concentrations (C0) throughout the 12-month follow-up. A limited blood sampling strategy was adopted to compare the pharmacokinetics of the two formulations at the end of weeks 1 to 4, and of weeks 13, 26, 39, 52. The influence of any difference between the pharmacokinetics of Neoral and Sandimmune on either efficacy or toxicity of the drug was investigated during the follow-up period. Patients in the Neoral and the Sandimmune groups were matched demographically. There were no differences in dose-normalized blood cyclosporine concentrations measured predose (C0) or 6 hours postdose between the two groups. However, the measurement at 2 hours postdose (C2) and the total AUC0-6 were significantly greater in the Neoral group in both CF and non-CF patients at all visits (p < 0.001). Non-CF patients required 9% lower doses of Neoral to achieve comparable C0 measurements to those patients receiving Sandimmune. However, patients with CF required 2 to 3 times the dose of both Neoral and Sandimmune to achieve the same C0 as non-CF patients. The linear rejection rate in the Sandimmune group was 1.87 episodes per patient year, which was similar to the rejection rate of 1.97 episodes per patient year in the Neoral group. Serial lung function, blood biochemistry and hematology, mortality and the incidence of severe renal dysfunction, hypertension, infection, seizures, and new-onset diabetes were all similar in the two groups. Despite equivalent C0, those in the Neoral group were consistently exposed to greater blood cyclosporine concentrations during the dosing interval than those in the Sandimmune group. This did not increase the incidence of serious cyclosporine-associated side effects or influence the rate of acute rejection either. When data from the Neoral and Sandimmune groups were combined, measurements of C0 but not C2 or C6 were associated with the risk of acute lung allograft rejection.

Adult↗