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Vivek N Ahya

Publications and source records attributed to Vivek N Ahya.

10 recordsLinked to original sources

Effects of lung allocation score on waiting list rankings and transplant procedures.

The effect of the new lung allocation score on ranking of patients on the waiting list and the number of transplants performed is not known. We assessed this effect on our lung transplant program and conducted a simulation of lung transplants for the first few months of the new system, using the old waiting lists. Patients with idiopathic pulmonary fibrosis had improved rankings and patients with emphysema had worse rankings, but the number of transplants for each disease category did not change significantly compared with the simulated transplants.

Algorithms↗

Multiple variables affecting blood usage in lung transplantation.

BACKGROUND: A few publications have reported on the role of variables affecting blood component usage during lung transplantation. METHODS: Transfusion records for lung transplantation patients at the Hospital of the University of Pennsylvania (November 1991 to July 2004) were reviewed. Bivariate analyses and regression models were used to correlate usage of packed red blood cells (RBC), fresh-frozen plasma (FFP) and platelets (PLT) with variables such as disease, number of pulmonary lobes (1 or 2), cardiopulmonary bypass (CPB) status and time on bypass. RESULTS: Among 376 patients examined during the study period, blood product usage (in units) was significantly higher in double- than in single-lung recipients (RBC, 5.76 vs 1.21; FFP, 5.55 vs 1.10; PLT, 1.15 vs 0.16; p < 0.001). Patients on CPB also used significantly more units (RBC, 8.28 vs 1.45; FFP, 9.70 vs 0.73; PLT, 1.86 vs 0.14; p < 0.001), correlating with time on bypass. Patients transplanted for Eisenmenger syndrome (ES) and cystic fibrosis (CF) received significantly more blood products than those transplanted for other diseases (RBC, ES = 17.91 vs CF = 7.31 vs all others <2.00; FFP, ES = 19.18 vs CF = 5.72 vs others <2.00; PLT, ES = 4.73 vs CF = 1.22 vs others <0.40; p < 0.001). A regression model identified variables predictive of blood product usage, including the number of lungs transplanted, CPB status, disease and patient age. CONCLUSIONS: Patients receiving double-lung transplantations, on CPB, or transplanted for ES and CF exhibited a very highly statistically significant demand (p < 0.001) for more blood products. Additional selected variables differentially predicted usage. These data will help transplant surgeons and transfusion medicine specialists better anticipate and prepare blood products for use in lung transplantation.

Adult↗

The effect of primary graft dysfunction on survival after lung transplantation.

RATIONALE: Primary graft dysfunction is a severe acute lung injury syndrome after lung transplantation. Long-term outcomes of subjects with primary graft dysfunction have not been studied. OBJECTIVES: We sought to test the relationship of primary graft dysfunction with both short- and long-term mortality using a large registry. METHODS: We used data collected on 5,262 patients in the United Network for Organ Sharing/International Society of Heart and Lung Transplantation registry between 1994 and 2000. We assessed outcomes in all subjects; to assess potential bias from the effects of early mortality, we also evaluated subjects who survived at least 1 year, using Cox proportional hazards models with time-varying covariates. MAIN RESULTS: The overall incidence of primary graft dysfunction was 10.2% (95% confidence intervals [CI], 9.2, 10.9). The incidence did not vary by year over the period of observation (p = 0.22). All-cause mortality at 30 days was 42.1% for primary graft dysfunction versus 6.1% in patients without graft dysfunction (relative risk = 6.95; 95% CI, 5.98, 8.08; p < 0.001); among subjects who died by 30 days, 43.6% had primary graft dysfunction. Among patients surviving at least 1 year, those who had primary graft dysfunction had significantly worse survival over ensuing years (hazard ratio, 1.35; 95% CI, 1.07, 1.70; p = 0.011). Adjustment for clinical variables including bronchiolitis obliterans syndrome did not change this relationship. CONCLUSION: Primary graft dysfunction contributes to nearly half of the short-term mortality after lung transplantation. Survivors of primary graft dysfunction have increased risk of death extending beyond the first post-transplant year.

Cause of Death↗

Hemodynamics and survival of patients with portopulmonary hypertension.

It is not known whether patients with pulmonary arterial hypertension associated with portal hypertension (portopulmonary hypertension (PPHTN) have different disease characteristics from those of patients with other forms of pulmonary arterial hypertension. We performed a retrospective cohort study of patients with PPHTN and patients with pulmonary arterial hypertension that was idiopathic, familial, or associated with anorexigen use (IPAH) to determine whether hemodynamics or survival were different between these groups. We included consecutive patients who underwent initial pulmonary artery catheterization and vasodilator testing at our center between January 1997 and May 2001 and who were followed until January 2004. Patients with PPHTN (N = 13) had a higher cardiac index and lower pulmonary vascular resistance than patients with IPAH (N = 33) (P < or = 0.001). Right atrial pressure and pulmonary artery pressure were similar between the groups. Patients with PPHTN had a higher risk of death in multivariate analysis (hazard ratio: [HR] = 2.8, 95% CI 1.04-7.4; P = 0.04). These findings were not affected by adjustment for differences in laboratory values, hemodynamics, or therapy. In conclusion, patients with PPHTN have a higher risk of death than that of patients with IPAH, despite having a higher cardiac index and lower pulmonary vascular resistance. Future studies of the specific mechanisms of and therapy for pulmonary arterial hypertension should focus on the distinctions between the different forms of this disease.

Adult↗

Noninfectious pulmonary complications after lung transplantation.

This article reviews several important noninfectious pulmonary complications that threaten survival, pulmonary function, and quality of life after lung transplantation. Topics reviewed include primary graft dysfunction (PGD), native lung hyperinflation, anastomotic complications, phrenic nerve injury, pleural complications, lung cancer, pulmonary toxicity associated with immunosuppressive medications, and exercise limitation.

Humans↗

Renal and vestibular toxicity due to inhaled tobramycin in a lung transplant recipient.

Chronic rejection is the major hurdle to long-term survival after lung transplantation. Endobronchial infection with Pseudomonas aeruginosa is common in patients with chronic rejection and this may further contribute to deterioration of the allograft. Inhaled tobramycin is commonly used to treat P aeruginosa airways infection in patients with cystic fibrosis. The safety of inhaled tobramycin in transplant recipients, however, has not been established. We describe the first report of a lung transplant recipient who developed renal failure and vestibular injury after receiving inhaled tobramycin. We review the literature regarding the safety of inhaled tobramycin and discuss potential mechanisms that may promote systemic toxicity in transplant recipients.

Administration, Inhalation↗

Serum protein electrophoresis abnormalities in adult solid organ transplant patients with post-transplant lymphoproliferative disorder.

Post-transplant lymphoproliferative disorder (PTLD) is an Epstein-Barr virus (EBV) associated malignancy that occurs in the setting of pharmacologic immunosuppression used after organ transplantation. The presence of monoclonal gammopathy (MG) after organ transplantation is a risk factor for the development of PTLD. We retrospectively explored the characteristics of serum protein electrophoresis (SPEP) in 38 adult solid organ transplant patients with biopsy proven PTLD and SPEP. Twenty-three (61%) had MG with nine (24%) showing multiple MG. Background gammaglobulin levels were abnormal in 13 (34%) patients with five (13%) and eight (21%) having polyclonal hypergammaglobulinemia or hypogammaglobulinemia, respectively. Hypogammaglobulinemia was correlated with the presence of MG (p = 0.01) and polymorphic B-cell hyperplasia histology (p = 0.01). No correlation between SPEP findings and overall survival were noted. With median follow-up of 116 wk (range 2-261 wk), 21 (55%) patients are alive with 20 (53%) in complete remission. Response to reduction in immunosuppression was correlated with improved overall survival (262 wk vs. 68 wk, p = 0.003). Persistence of MG after complete response of the PTLD did not predict relapse. There is a high incidence of MG and gammaglobulin abnormalities in patients with PTLD.

Adult↗

Impact of primary graft failure on outcomes following lung transplantation.

STUDY OBJECTIVES: Primary graft failure (PGF) is a severe acute lung injury syndrome that occurs following lung transplantation. We compared the clinical outcomes of patients who developed PGF with those who did not. METHODS: We conducted a retrospective cohort study including 255 consecutive lung transplant procedures. PGF was defined as (1) diffuse alveolar opacities developing within 72 h of transplantation, (2) an arterial partial pressure of oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio of < 200 beyond 48 h postoperatively, and (3) no other secondary cause of graft dysfunction. PGF was tested for acceptance with 30-day and all-cause hospital mortality rates, overall survival, hospital length of stay (HLOS), duration of mechanical ventilation, and best 6-min walk test (6MWT) distance achieved within 12 months. SETTING: Academic medical center. RESULTS: The overall incidence of PGF was 11.8% (95% confidence interval [CI], 7.9 to 15.9%). The all-cause mortality rate at 30 days was 63.3% in patients with PGF and 8.8% in patients without PGF (relative risk [RR], 7.15; 95% CI, 4.34 to 11.80%; p < 0.001). A total of 73.3% of patients with PGF died during hospitalization vs 14.2% of patients without PGF (RR, 5.18%; 95% CI, 3.51 to 7.63; p < 0.001). The median HLOS in 30-day survivors was 47 days in patients with PGF vs 15 days in those without PGF (p < 0.001), and the mean duration of mechanical ventilation was 15 days in patients with PGF vs 1 day in those without PGF (p < 0.001). By 12 months, a total of 28.5% of survivors with PGF achieved a normal age-appropriate 6MWT distance vs 71.4% of survivors without PGF at 12 months (p = 0.014). The median best 6MWT distance achieved within the first 12 months was 1,196 feet in patients with PGF vs 1,546 feet in those without PGF (p = 0.009). CONCLUSIONS: PGF has a significant impact on mortality, HLOS, and duration of mechanical ventilation following lung transplantation. Survivors of PGF have a protracted recovery with impaired physical function up to 1 year following transplantation.

Exercise Test↗

Pulmonary complications of solid organ and hematopoietic stem cell transplantation.

The ability to successfully transplant solid organs and hematopoietic stem cells represents one of the landmark medical achievements of the twentieth century. Solid organ transplantation has emerged as the standard of care for select patients with severe vital organ dysfunction and hematopoietic stem cell transplantation has become an important treatment option for patients with a wide spectrum of nonmalignant and malignant hematologic disorders, genetic disorders, and solid tumors. Although advances in surgical techniques, immunosuppressive management, and prophylaxis and treatment of infectious diseases have made long-term survival an achievable goal, transplant recipients remain at high risk for developing a myriad of serious and often life-threatening complications. Paramount among these are pulmonary complications, which arise as a consequence of the immunosuppressed status of the recipient as well as from such factors as the initial surgical insult of organ transplantation, the chemotherapy and radiation conditioning regimens that precede hematopoietic stem cell transplantation, and alloimmune mechanisms mediating host-versus-graft and graft-versus-host responses. As the population of transplant recipients continues to grow and as their care progressively shifts from the university hospital to the community setting, knowledge of the pulmonary complications of transplantation is increasingly germane to the contemporary practice of pulmonary medicine.

Hematopoietic Stem Cell Transplantation↗