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1.
J Card Surg ; 26(6): 591-5, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21995559

RESUMEN

OBJECTIVES: Renal transplant recipients have high mortality from cardiac causes and are frequently in need of coronary interventions. Surgical coronary revascularization is associated with significant morbidity and mortality in this patient population. This study was undertaken to evaluate outcomes of on-pump versus off-pump revascularization in renal transplant recipients. METHODS: We retrospectively reviewed 43 renal transplant recipients who underwent surgical coronary revascularization with functioning allografts. Revascularization was performed on-pump [coronary artery bypass grafting (CABG)] in 21 patients and off-pump [off-pump coronary artery bypass (OPCAB)] in 22 patients. RESULTS: Preoperative characteristics did not differ between the two groups except for age and incidence of prior sternotomy. Total operative time and transfusion requirements were similar. The on-pump group received a higher number of bypass grafts (p = 0.03). Overall 30-day, one-year, five-year, and eight-year survival was 90%, 76%, 61%, and 32% for CABG group, and 95%, 86%, 62%, and 48% for OPCAB group (p = 0.53). The postoperative peak creatinine was higher in the CABG patients than in OPCAB patients (p = 0.04). At discharge, there was no difference in mean creatinine between the two groups. The rate of return to permanent dialysis after revascularization was similar (28% for CABG and 22% for OPCAB, p = 0.73). There was no difference in dialysis-free survival up to eight-years postrevascularization (p = 0.63). CONCLUSIONS: Despite higher mortality risk, surgical coronary revascularization can be performed safely in renal transplant recipients. OPCAB resulted in no improvement in patient survival or renal allograft function compared to on-pump revascularization.


Asunto(s)
Puente de Arteria Coronaria/métodos , Enfermedad de la Arteria Coronaria/cirugía , Fallo Renal Crónico/cirugía , Trasplante de Riñón , Causas de Muerte/tendencias , Puente de Arteria Coronaria Off-Pump/métodos , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/mortalidad , Masculino , Persona de Mediana Edad , Pennsylvania/epidemiología , Estudios Retrospectivos , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
2.
COPD ; 7(3): 186-91, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20486817

RESUMEN

ABSTRACT The association of osteoporosis with COPD is well established, but the relationship between systemic inflammatory mediators and bone metabolism has not been explored. Plasma samples from 40 COPD patients awaiting lung transplantation were analyzed for 27 inflammatory mediators using a multiplex protein array. C-telopeptide type I collagen (CTx), a marker of bone resorption, was measured with ELISA, and N-terminal procollagen propeptide (P1NP), a marker of bone formation, was ascertained with a radioimmunoassay. Associations between inflammatory mediators versus CTx and P1NP with adjustments for steroid and bisphosphonate use were determined. Mean age was 59 years (+/- 6) and FEV(1) was 23.5% (+/- 8.3%) predicted. Ninety-five percent of the subjects had low bone mineral density measured by dual x-ray absorptiometry (DXA). Tumor necrosis factor alpha and interleukin 4 were positively associated with CTx and P1NP. RANTES and eotaxin were inversely associated with CTx and P1NP. Interleukin 2 and interferon gamma were also directly associated with P1NP. Biologically plausible systemic mediators are associated with bone metabolism in patients with severe COPD, offering potential insight into risk factors and underlying mechanisms of bone disease. Furthermore, they may be useful in monitoring disease activity, and serve as targets for biological therapy.


Asunto(s)
Huesos/metabolismo , Mediadores de Inflamación/sangre , Interleucina-4/sangre , Osteoporosis/sangre , Enfermedad Pulmonar Obstructiva Crónica/sangre , Factor de Necrosis Tumoral alfa/sangre , Absorciometría de Fotón , Adulto , Anciano , Biomarcadores/sangre , Colágeno Tipo I/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/etiología , Procolágeno , Pronóstico , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Radioinmunoensayo , Estudios Retrospectivos , Factores de Riesgo
3.
Transplantation ; 86(2): 342-7, 2008 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-18645500

RESUMEN

BACKGROUND: The hallmark of humoral rejection is the presence of subendothelial C4d in the allograft. A simultaneous determination of vascular C4d with soluble C4d in broncho-alveolar lavage fluid (BAL) and circulating anti-human leukocyte antigen (HLA) antibodies (HLA-Ab) has not been reported in lung transplantation. METHODS: Forty-two consecutive lung-transplant patients were included in this cross-sectional study. The presence and specificity of HLA-Ab was determined at the same frequency with transbronchial biopsies. Soluble C4d levels were measured by enzyme-linked immunosorbent assay in all 42 patients. In a subgroup of 32 patients with available timely matched paraffin-embedded tissue sections, the vascular C4d deposition was also assessed. RESULTS: The presence of HLA-Ab in 16 patients was associated with biopsy-proven acute rejection (10/16 vs. 3/16, P<0.01) and increased immunosuppression (13/16 vs. 4/16, P<0.005). Pulmonary function was also decreased in patients with HLA-Ab (mean forced expiratory volume in 1 second=49%) when compared with the control group (mean forced expiratory volume in 1 second=66%, P<0.05). Nine patients exhibited specific vascular C4d deposition and in eight of nine (89%) cases HLA-Ab were detected, versus 8 of 23 (35%) in C4d-negative patients (P<0.05). Soluble C4d in BAL was highly (>0.5 microg/mL) elevated in patients with HLA-Ab and vascular C4d and was moderately (0.2 microg/mL) increased in patients with antibodies but C4d-negative. In contrast, only a slight elevation of soluble C4d (<0.1 microg/mL) was detected in patients without HLA-specific antibodies. CONCLUSIONS: The association of HLA-specific antibodies with vascular C4d deposition and soluble C4d in BAL, in addition to the reduced pulmonary function, might constitute a diagnostic triad for antibody-mediated rejection in lung transplant patients.


Asunto(s)
Lavado Broncoalveolar , Complemento C4b/química , Antígenos HLA/química , Trasplante de Pulmón/métodos , Fragmentos de Péptidos/química , Adulto , Anciano , Biopsia , Líquido del Lavado Bronquioalveolar , Femenino , Rechazo de Injerto , Humanos , Isoanticuerpos/química , Pulmón/patología , Masculino , Persona de Mediana Edad
4.
Transpl Immunol ; 15(3): 235-40, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16431292

RESUMEN

BACKGROUND: The influence of ABCB1 (MDR1) polymorphisms on tacrolimus dosing has been questioned in previous studies with contradictory findings, possibly due to the association between CYP3A5 polymorphisms and tacrolimus dosing. The objective of this study was to assess the effect of ABCB1 haplotypes from 3 distinct polymorphic sites on the tacrolimus level/dose [L/D] in lung transplant patients limited to CYP3A5 *3/*3 non-expressors. METHOD: A total of 91 lung transplant patients treated primarily with tacrolimus and prednisone were enrolled, and clinical information on drug dosing and blood levels was collected. The [L/D] was calculated for patients receiving tacrolimus at 1, 3, 6, 9 and 12 months post transplant. ABCB1 polymorphisms at C1236T, G2677T, and C3435T were assessed by PCR amplification and DNA sequencing. Haplotypes were estimated by Arlequin ver.2.00. Haplotype effects on tacrolimus [L/D] were assessed by two-way ANOVA. RESULTS: Of the 10 haplotypes, CGC, TTT and CGT accounted for 44.1%, 40.7% and 7.6% of the total haplotypes, respectively. The tacrolimus [L/D] value in the CGC-CGC patients was significantly lower than in patients with CGC-TTT and TTT-TTT genotypes at the first month (mean [L/D]=1.45 versus 3.10 and 3.97 ngxmL(-)(1) /mg/day), and throughout the first post transplant year. CONCLUSION: This study demonstrates that ABCB1 haplotypes derived from three common polymorphisms are associated with tacrolimus dosing in lung transplant patients when eliminating the confounder CYP3A5 genotype.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Inmunosupresores/administración & dosificación , Trasplante de Pulmón , Transportadores de Anión Orgánico/genética , Polimorfismo Genético , Tacrolimus/administración & dosificación , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Adulto , Citocromo P-450 CYP3A , Sistema Enzimático del Citocromo P-450/biosíntesis , Femenino , Haplotipos , Humanos , Masculino , Transportadores de Anión Orgánico/metabolismo , Factores de Tiempo
5.
J Thorac Cardiovasc Surg ; 130(2): 528-37, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16077423

RESUMEN

OBJECTIVES: Acute and chronic rejection remain unresolved problems after lung transplantation, despite heavy multidrug immunosuppression. In turn, the strong immunosuppression has been responsible for mortality and pervasive morbidity. It also has been postulated to interdict potential mechanisms of alloengraftment. METHODS: In 48 lung recipients we applied 2 therapeutic principles: (1) recipient pretreatment with antilymphoid antibody preparations (Thymoglobulin [SangStat, Fremont, Calif] or Campath [alemtuzumab; manufactured by ILEX Pharmaceuticals, LP, San Antonio, Tex; distributed by Berlex Laboratories, Richmond, Calif]) and (2) minimal posttransplant immunosuppression with tacrolimus monotherapy or near-monotherapy. Our principal analysis was of the events during the critical first 6 posttransplant months of highest immunologic and infectious disease risk. Results were compared with those of 28 historical lung recipients treated with daclizumab induction and triple immunosuppression (tacrolimus-prednisone-azathioprine). RESULTS: Recipient pretreatment with both antilymphoid preparations allowed the use of postoperative tacrolimus monotherapy with prevention or control of acute rejection. Freedom from rejection was significantly greater with Campath than with Thymoglobulin (P = .03) or daclizumab (P = .05). After lymphoid depletion with Thymoglobulin or Campath, patient and graft survival at 6 months was 90% or greater. Patient and graft survival after 9 to 24 months is 84.2% in the Thymoglobulin cohort, and after 10 to 12 months, it is 90% in the Campath cohort. There has been a subjective improvement in quality of life relative to our historical experience. CONCLUSION: Our results suggest that improvements in lung transplantation can be accomplished by altering the timing, dosage, and approach to immunosuppression in ways that might allow natural mechanisms of alloengraftment and diminish the magnitude of required maintenance immunosuppression.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Antineoplásicos/uso terapéutico , Suero Antilinfocítico/uso terapéutico , Rechazo de Injerto/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Trasplante de Pulmón/inmunología , Tacrolimus/uso terapéutico , Adulto , Anciano , Alemtuzumab , Anticuerpos Monoclonales Humanizados , Femenino , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Prednisona/uso terapéutico , Análisis de Supervivencia , Resultado del Tratamiento
6.
Ann Thorac Surg ; 100(6): 2330-3, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26652524

RESUMEN

Although extracorporeal membrane oxygenation (ECMO) has been used frequently as a bridge to primary lung transplantation, active centers are conservative with this approach in patients requiring redo lung transplantation. We report the use of extracorporeal carbon dioxide removal, using the Hemolung respiratory assist system, as a prolonged bridge to lung transplantation, and the first use of the Hemolung as a bridge to redo lung transplantation. Hemolung support improved the patient's clinical status and allowed redo lung transplantation.


Asunto(s)
Oxigenación por Membrana Extracorpórea/instrumentación , Trasplante de Pulmón , Insuficiencia Respiratoria/terapia , Adulto , Diseño de Equipo , Humanos , Masculino , Factores de Tiempo
7.
J Heart Lung Transplant ; 23(5): 541-6, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15135368

RESUMEN

BACKGROUND: Our previous studies demonstrated that cytokine gene polymorphisms are related to acute rejection in pediatric heart transplantation; a decreased tumor necrosis factor (TNF)-alpha production genotype combined with an increased or intermediate interleukin (IL)-10 production genotype was associated with the smallest incidence of acute rejection. The objective of this study was to determine whether cytokine genotypes TNF-alpha, IL-10, IL-6, interferon-gamma, and transforming growth factor beta were associated with acute persistent rejection after lung transplantation. METHODS: Cytokine genotyping was performed in 119 adult lung transplantation recipients who underwent surveillance transbronchial biopsies during their first year after transplantation. We categorized recipients with acute persistent rejection if they had 2 consecutive biopsy specimens at >/=Grade A2 despite anti-rejection treatment. We performed cytokine genotyping using the polymerase chain reaction-sequence specific primers technique, with a commercially available kit. RESULTS: We analyzed the IL-10 genotype in 116 patients. For the increased IL-10 production genotype, 7 of 20 patients (35%) were persistent rejecters. In comparison, 57 of 96 patients (59%) with intermediate or decreased IL-10 production genotype had acute persistent rejection (p = 0.046). For IL-10 haplotypes associated with intermediate IL-10 production, 30 of 45 patients with GCC/ACC haplotype (67%) had acute persistent rejection compared with 10 of 22 patients with GCC/ATA (45%). In the patients with intermediate IL-10 production, 17 of 22 (77%) with IL-10 GCC/ACC and IL-6 G/C had acute persistent rejection, whereas only 2 of 7 patients (29%) with IL-10 GCC/ATA and IL-6 G/G had acute persistent rejection (p = 0.018). CONCLUSIONS: In lung transplant recipients, the increased IL-10 production genotype protects against acute persistent rejection when compared with the intermediate or decreased IL-10 production genotypes. The intermediate IL-10 production genotype in lung transplant recipients can be differentiated into 2 haplotype responses, with the GCC/ACC haplotype associated more with acute persistent rejection. In lung transplant recipients, the immunomodulatory effects of IL-6 are differentiated in the G/C and G/G alleles in conjunction with IL-10 haplotypes, with G/C being associated with more acute persistent rejection in conjunction with the IL-10 GCC/ACC haplotype. Future pharmacogenomic models may incorporate these associations with acute persistent rejection in lung transplant recipients to formulate individualized therapeutic regimens.


Asunto(s)
Rechazo de Injerto/genética , Interleucina-10/biosíntesis , Trasplante de Pulmón , Enfermedad Aguda , Femenino , Genotipo , Haplotipos , Humanos , Interferón gamma/biosíntesis , Interleucina-6/biosíntesis , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Factor de Crecimiento Transformador beta/biosíntesis , Factor de Necrosis Tumoral alfa/biosíntesis
8.
J Clin Pharmacol ; 44(2): 135-40, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14747421

RESUMEN

Tacrolimus is a potent immunosuppressive agent used in lung transplantation and is a substrate for both P-glycoprotein (P-gp, encoded by the gene MDR1) and cytochrome (CYP) P4503A. A previous study by the authors identified a correlation between the tacrolimus blood level per dose with CYP3A5 and MDR1 gene polymorphisms in pediatric heart transplant patients. The objective of this study was to confirm the influence of these polymorphisms on tacrolimus dosing in adult lung transplant patients. Adult lung transplant patients who had been followed for at least 1 year after lung transplantation were studied. Tacrolimus blood level (ng/mL) per dose (mg/day) at 1, 3, 6, 9, and 12 months after transplantation was calculated as [L/D]. DNA was extracted from blood. MDR1 3435 CC, CT, and TT; MDR1 2677 GG, GT, and TT; and CYP3A5*1 (expressor) and *3 (nonexpressor) genotypes were determined by PCR amplification, direct sequencing, and sequence evaluation. Eighty-three patients were studied. At 1, 3, 6, 9, and 12 months after the transplant, a significant difference in [L/D] was found between the CYP3A5 expressor versus nonexpressor genotypes (mean +/- SD of 1.49 +/- 0.88 vs. 3.11 +/- 4.27, p = 0.01; 1.23 +/- 0.82 vs. 3.44 +/- 8.97, p = 0.05; 1.32 +/- 0.96 vs. 3.81 +/- 6.66, p = 0.005; 0.95 +/- 1.19 vs. 3.74 +/- 5.98, p = 0.0015; and 0.45 +/- 0.2 vs. 3.76 +/- 6.75, p = 0.0001, respectively). MDR1 G2677T and C3435T genotypes had only minimal effects on [L/D] at 1 and 3 months after transplantation. This study confirms the relationship of CYP3A5 polymorphisms to tacrolimus dosing in organ transplant patients. CYP3A5 expressor genotypes required a larger tacrolimus dose to achieve the same blood levels than the CYP3A5 nonexpressors at all time points during the first posttransplant year. This was not uniformly true for MDR1. The authors therefore conclude that tacrolimus dosing in adult lung transplant patients is associated with CYP3A5 gene polymorphisms.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Inmunosupresores/administración & dosificación , Trasplante de Pulmón , Polimorfismo Genético , Tacrolimus/administración & dosificación , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Secuencia de Bases , Citocromo P-450 CYP3A , Relación Dosis-Respuesta a Droga , Femenino , Expresión Génica , Genes MDR , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
9.
J Thorac Cardiovasc Surg ; 147(1): 270-5, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23177121

RESUMEN

OBJECTIVES: Cardiovascular complications are a major cause of morbidity and mortality among renal transplant recipients. This study assessed perioperative risk factors for mortality and long-term outcomes in renal transplant recipients who underwent cardiac surgery. METHODS: From 1999 to 2010, 92 renal transplant recipients with a functioning allograft underwent cardiac surgery at our institution. Cardiac procedures included coronary artery bypass grafting (43 patients, 46%), isolated valve surgery (17 patients, 18%), combined coronary artery bypass grafting and valve surgery (18 patients, 19%), and aortic procedures (7 patients, 7%). RESULTS: Transient renal failure requiring dialysis occurred in 20 of 92 patients (21%), with 3 not recovering renal function and returning to a permanent dialysis regimen while in the hospital. After cardiac surgery 30-day, 1-year, 5-year, and 8-year survival rates were 89%, 72%, 47%, and 30%, respectively. Freedom from dialysis was 90% after 1 year, 66% after 5 years, and 49% after 8 years. Risk factors for 30-day mortality were age > 65 years, left ventricle ejection fraction < 35%, and a combined cardiac procedure. Pulmonary hypertension and diabetes were risk factors for death from a cardiac cause after discharge. Diabetes, dyslipidemia, preoperative use of an intra-aortic balloon pump, postoperative creatinine > 2 mg/dL, and transient renal failure requiring dialysis were associated with a permanent dialysis requirement after cardiac surgery. CONCLUSIONS: Cardiac surgery in patients receiving renal transplant who have functioning allograft has acceptable outcomes. If combined procedures are required, patients should be carefully considered. Transient postoperative renal impairment, even if resolved at discharge, increases the risk for allograft failure during long-term follow-up.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Supervivencia de Injerto , Trasplante de Riñón/efectos adversos , Insuficiencia Renal/etiología , Anciano , Procedimientos Quirúrgicos Cardíacos/mortalidad , Femenino , Tasa de Filtración Glomerular , Supervivencia de Injerto/efectos de los fármacos , Humanos , Inmunosupresores/uso terapéutico , Estimación de Kaplan-Meier , Trasplante de Riñón/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Selección de Paciente , Modelos de Riesgos Proporcionales , Recuperación de la Función , Diálisis Renal , Insuficiencia Renal/mortalidad , Insuficiencia Renal/fisiopatología , Insuficiencia Renal/terapia , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
10.
J Heart Lung Transplant ; 33(7): 741-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24726683

RESUMEN

BACKGROUND: Delayed chest closure (DCC) after lung transplantation is a viable option to be taken in the cases of prolonged cardiopulmonary bypass time, prolonged ischemic time, coagulopathic problems or oversized donor lung grafts. Decision-making for DCC in the operating room remains challenging to surgeons, because the impact of DCC on outcomes after lung transplantation has not yet been fully elucidated. METHODS: We performed a retrospective review of 90 lung transplantations with DCC and 783 cases with primary chest closure to clarify the reasons for DCC, complications of DCC, and the risk factors for adverse outcomes. RESULTS: The 30- and 90-day mortality in the DCC group was 7.8% and 9.9%, respectively. Early post-operative bleeding and severe primary graft dysfunction (PGD) were higher in the DCC group (p<0.05). In multivariate analysis, prolonged cardiopulmonary bypass use (>4 hours), post-operative extracorporeal oxygen requirement and use of a DCC technique with open skin and retracted ribs were significantly associated with mortality (p<0.05), whereas prolonged duration of DCC was not. In a matched cohort study to compare the results of a DCC technique with skin closure to similarly matched controls with primary closure, DCC contributed to significantly decreased incidence of severe PGD (9.6% vs. 26%, p<0.05), leading to an improved post-transplant survival and functional status as compared with primary closure. CONCLUSIONS: Our technical approaches to prevent possible problems in DCC cases are described. DCC can be safely performed with acceptable procedure-related risks. DCC should not be considered a sub-optimal option after lung transplantation.


Asunto(s)
Trasplante de Pulmón/métodos , Evaluación de Resultado en la Atención de Salud , Toracotomía/métodos , Técnicas de Cierre de Heridas , Adulto , Puente Cardiopulmonar , Estudios de Cohortes , Femenino , Humanos , Pulmón/patología , Pulmón/cirugía , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Isquemia Tibia
11.
Transplantation ; 98(8): 903-8, 2014 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-24825527

RESUMEN

BACKGROUND: A shortage of donors has compelled the use of extended-criteria donor organs in lung transplantation. The purpose of this study was to evaluate the impact of using older donors on outcomes after lung transplantation using current protocols. METHODS: From January 2003 to August 2009, 593 lung transplants were performed at our institution. We compared 87 patients (14.7%) who received lungs from donors aged 55 years or older with 506 patients who received lungs from donors less than 55 years old. We also examined risk factors for mortality in recipients of lungs from older donors. RESULTS: The incidence of major complications including severe primary graft dysfunction and early mortality rates were similar between the groups. However, posttransplant peak FEV1 was lower in the patients who received lungs from older donors (71.7% vs. 80.7%, P<0.05). In multivariate analysis, recipient pulmonary hypertension (transpulmonary pressure gradient >20 mm Hg) and prolonged intraoperative cardiopulmonary bypass were significant risk factors for mortality in the recipients of lungs from older donors. CONCLUSIONS: This large, single-center experience demonstrated that transplanting lungs from donors older than 55 years did not yield worse short- or long-term outcomes as compared with transplanting lungs from younger donors. However, transplanting lungs from older donors into recipients with pulmonary hypertension or recipients who required prolonged cardiopulmonary bypass increased the risk for mortality. Although lungs from older donors should not be excluded because of donor age alone, surgeons should carefully consider their patient selection criteria and surgical plans when transplanting lungs from older donors.


Asunto(s)
Trasplante de Pulmón , Donantes de Tejidos , Adulto , Factores de Edad , Anciano , Puente Cardiopulmonar , Femenino , Volumen Espiratorio Forzado , Humanos , Trasplante de Pulmón/efectos adversos , Trasplante de Pulmón/mortalidad , Masculino , Persona de Mediana Edad , Factores de Riesgo , Trasplante Homólogo , Resultado del Tratamiento
12.
J Thorac Cardiovasc Surg ; 145(4): 1065-1071, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23332185

RESUMEN

BACKGROUND: Preoperative extracorporeal membrane oxygenation (ECMO) is a risk factor for poor outcome and currently considered a contraindication to lung transplantation. The lung allocation score system was introduced in May 2005 and prioritizes lung allocation to those with the greatest respiratory impairment. The purpose of this study is to determine whether ECMO as a bridge to lung transplantation is an acceptable option to support those in respiratory failure until donor lungs become available in the lung allocation score era. METHOD: A retrospective review of 715 consecutive lung transplants performed between May 2005 and September 2011 was conducted using a prospectively collected institutional registry database. Twenty-four lung transplants (3.4%) were performed in the 31 patients with attempted pretransplant ECMO; 7 patients who received ECMO patients did not survive or were deemed unfit for transplantation. These patients were compared with a control group of 691 patients who did not receive pretransplant ECMO. RESULTS: The duration of pretransplant ECMO was 171 ± 242 hours (median, 91 hours). Venovenous ECMO was used for respiratory failure in 15 patients, whereas venoarterial ECMO was used for circulatory collapse due to pulmonary hypertension in 9 patients. Patients in the retransplant ECMO group were younger (46 ± 15 years vs 57 ± 14 years, P < .01) compared with the control group, with no difference in recipient gender (male/female: 10/14 vs 380/311), donor age (33 ± 14 years vs 36 ± 15 years), or donor gender (male/female: 10/14 vs 352/339). Emphysema was less common (1, 4% vs 260, 38%, P < .01), and cystic fibrosis (5, 21% vs 72, 10%, P = .09), redo lung transplant (3, 13% vs 28, 4%, P = .08), and bronchiectasis (2, 8% vs 6, 1%, P = .03) were more common in the pretransplant ECMO group. Patients in the pretransplant ECMO group had a significantly higher lung allocation score (87 ± 9 vs 44 ± 15, P < .01). All patients in the pretransplant ECMO group underwent double lung transplants on pump (cardiopulmonary bypass/ECMO), and single lung transplants were performed in 171 patients (25%) and pump was used in 243 patients (35%) in the control group. The cardiopulmonary bypass time was longer in the pretransplant ECMO group (277 ± 69 minutes vs 225 ± 89 minutes, P = .02), with no difference in ischemic time (343 ± 93 minutes vs 330 ± 98 minutes, P = .54). Cadaveric lobar lung transplants were performed because of the urgency to overcome size mismatch with an oversized donor more frequently in 25% (n = 6, no mortality with the longest follow-up at 6 years) of patients in the pretransplant ECMO group versus 0.3% (n = 2) of patients in the control group (P < .01). Post-transplant ECMO was used for primary graft dysfunction in 13 patients (54%) in the pretransplant ECMO group and 41 patients (6%) in the control group (P < .01). The median hospital stay was 46 days in the pretransplant ECMO group versus 27 days in the control group (P = .16). The actuarial survivals after lung transplants at 1, 3, 6, 12, and 24 months were 96%, 88%, 83%, 74%, and 74%, respectively, in the pretransplant ECMO group, and 97%, 94%, 90%, 83%, and 74%, respectively, in the control group (P = .787). CONCLUSIONS: Although the incidence of primary graft dysfunction requiring post-transplant ECMO is higher and the hospital stay is longer in patients receiving pretransplant ECMO, the graft survival is good (2-year survival, 74%). ECMO is efficacious as a bridge to lung transplantation with good post-lung transplant outcomes.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Trasplante de Pulmón , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Estudios Retrospectivos
13.
Transplantation ; 95(3): 513-8, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23202531

RESUMEN

BACKGROUND: When selecting a donor for lung transplantation, it is generally believed that the best outcomes occur when the donor has no smoking history. Because we experienced unexpected adverse outcomes after transplant of lungs from teenaged donors with no smoking history, this study revisited the effects of donor smoking history in relation to age on transplant outcomes. METHODS: We conducted a retrospective review of 532 consecutive lung transplants performed at our institution. Most donors (293, 55%) had a history of smoking; 239 donors were nonsmokers. The smoking donors were further subgrouped based on consumption (<20, 20-40, or >40 pack-years). The nonsmoking donors were subgrouped by age (<20 years or ≥20 years). Recipients' characteristics and outcomes were compared. RESULTS: The recipients of lungs from donors with a smoking history showed better 5-year survival than recipients of lungs from nonsmokers (65.8% vs. 48.3%, P<0.05), but recipients of lungs from heavy smokers (>40 pack-years smoking history) exhibited a significantly higher incidence of severe primary graft dysfunction and higher short- and long-term mortality than the recipients of lungs from donors who smoked less. Surprisingly, recipients of lungs from teenaged donors with no smoking history exhibited a higher morbidity and mortality than recipients of lungs from adult nonsmoking donors but did not exhibit decreased posttransplant forced expiratory volume in 1 sec. CONCLUSIONS: In this large, single-center experience, the absence of smoking history in the donor did not result in better long-term outcomes after lung transplantation. Potential problems with lungs from teenaged donors with no smoking history were suggested.


Asunto(s)
Factores de Edad , Trasplante de Pulmón/mortalidad , Fumar/epidemiología , Donantes de Tejidos , Adulto , Anciano , Femenino , Rechazo de Injerto/epidemiología , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Fumar/fisiopatología , Tasa de Supervivencia , Resultado del Tratamiento
14.
Transplantation ; 96(4): 421-5, 2013 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-23736352

RESUMEN

BACKGROUND: Lung volume reduction surgery (LVRS) as a bridge to lung transplantation was first advocated in 1995 and published studies have supported the concept but with limited data. The risk-benefit tradeoffs of the combined procedure have not been thoroughly examined, although substantial information regarding LVRS has emerged. METHODS: Of 177 patients who underwent lung transplantation for end-stage emphysema between 2002 and 2009 at our center, 25 had prior LVRS (22 bilateral and 3 unilateral). Lung transplantation was performed 22.9±15.9 months after LVRS. We compared in-hospital morbidity, functional capacity, and long-term outcomes of patients who underwent LVRS before lung transplantation with a matched cohort of patients without prior LVRS to assess the influence of LVRS on posttransplantation morbidity and mortality. RESULTS: The incidence of postoperative bleeding requiring reexploration and the incidence of renal dysfunction requiring dialysis were higher in patients with LVRS before lung transplantation. Posttransplantation peak forced expiratory volume in 1 s was worse in patients with LVRS before lung transplantation (56.7% vs. 78.8%; P<0.05). Five-year survival was not significantly different (59.7% in patients with LVRS before lung transplantation vs. 66.2% in patients with lung transplantation alone). In multivariate analysis, age more than 65 years, prolonged cardiopulmonary bypass time, and severe pulmonary hypertension were significant predictors for mortality (P<0.05). CONCLUSIONS: Although LVRS remains a viable option as a bridge to lung transplantation in appropriately selected patients, LVRS before lung transplantation can impart substantial morbidity and compromised functional capacity after lung transplantation. LVRS should not be easily considered as a bridge to transplantation for all lung transplant candidates.


Asunto(s)
Trasplante de Pulmón/efectos adversos , Neumonectomía , Anciano , Estudios de Cohortes , Femenino , Humanos , Hipertensión Pulmonar/etiología , Trasplante de Pulmón/mortalidad , Trasplante de Pulmón/fisiología , Masculino , Persona de Mediana Edad , Neumonectomía/efectos adversos , Complicaciones Posoperatorias/etiología , Pronóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/cirugía , Enfisema Pulmonar/fisiopatología , Enfisema Pulmonar/cirugía , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
15.
Ann Thorac Surg ; 96(2): 451-6, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23773735

RESUMEN

BACKGROUND: With the implementation of the lung allocation score (LAS) system, an increased number of critically ill patients are considered for transplantation. However, LAS does not take size matching between donor and recipient lungs into consideration. Mortality on the waiting list is high (as high as 25%) for short-stature patients and for patients with restrictive lung disease. Here, we review our experience using cadaveric lobar lung transplantation as a surgical option in an attempt to decrease mortality while waiting. METHODS: We retrospectively reviewed patients with end-stage lung diseases and an LAS greater than 70 who underwent cadaveric lobar lung transplantation between 2010 and 2012 (n = 25) at our institution, a high-volume lung transplant center. Anatomic lobectomy was performed on all donor lungs before double lung transplantation. RESULTS: Median LAS was 85.6 (range, 72 to 94). Average waiting time after the patients' LAS was updated to greater than 70 was 10 days (range, 1 to 41). There were 2 in-hospital deaths. The 90-day and 1-year survivals were 88% and 76%, respectively. Patient major comorbidities included severe primary graft dysfunction requiring postoperative extracorporeal membrane oxygenation (7 patients), acute renal insufficiency (4 patients), and bleeding requiring reoperation (4 patients). No technical problems were identified, and repeated bronchoscopy demonstrated satisfactory healing of the bronchial stump after lobectomy. The average posttransplant peak for forced expiratory volume in 1 second was 85%. CONCLUSIONS: Our initial experience supports the option of lobar lung transplantation for critically ill patients whose opportunities for transplant are limited by their stature. Long-term functional studies are warranted.


Asunto(s)
Selección de Donante/normas , Trasplante de Pulmón/métodos , Adolescente , Adulto , Anciano , Humanos , Persona de Mediana Edad , Tamaño de los Órganos , Estudios Retrospectivos , Adulto Joven
16.
Ann Thorac Surg ; 93(5): 1592-7; discussion 1597, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22192755

RESUMEN

BACKGROUND: The lung allocation score (LAS) assigns organ allocation priority based on medical urgency and the likelihood of posttransplant survival. This study is a review of a single institutional experience for lung transplantation in the era of LAS. METHODS: We performed a retrospective review of 527 consecutive patients, from May 2005 to February 2010, who underwent lung transplant at our institution, comprising a high LAS group (LAS≥50, n=108) and a low LAS group (LAS<50, n=419). Kaplan-Meier and univariate analyses were performed to assess postoperative mortality as a primary outcome, and length of ventilator support and intensive care unit stay as secondary outcomes. Risk factors, including demographics, pulmonary status, and surgical and donor variables, were compared. Predictors of mortality were determined using a Cox proportional hazard model. RESULTS: Survivals after 30 days, 90 days, 1 year, and 3 years were 92.6%, 87.8%, 71.5%, and 52.0%, respectively, in the high LAS group, and 96.9%, 93.5%, 83.2%, and 73.9% in the low LAS group (p<0.001). The incidence of prolonged ventilator support and the need for tracheostomy were higher, and intensive care unit stay was longer in the high LAS group. In the high LAS group, ischemic time greater than 8 hours was an independent predictor for mortality (hazard ratio: 3.080; 95% confidence interval 1.101 to 8.161, p=0.032). CONCLUSIONS: Lung transplant in patients with high a LAS is associated with significantly decreased survival and increased complications compared with patients with a low LAS. Ischemic time greater than 8 hours is a significant predictor of death in patients with a high LAS.


Asunto(s)
Trasplante de Pulmón/mortalidad , Trasplante de Pulmón/métodos , Donantes de Tejidos/estadística & datos numéricos , Obtención de Tejidos y Órganos/estadística & datos numéricos , Adulto , Anciano , Análisis de Varianza , Estudios de Cohortes , Fibrosis Quística/diagnóstico , Fibrosis Quística/diagnóstico por imagen , Fibrosis Quística/mortalidad , Educación Médica Continua , Femenino , Estudios de Seguimiento , Rechazo de Injerto , Supervivencia de Injerto , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Enfermedad Pulmonar Obstructiva Crónica/cirugía , Fibrosis Pulmonar/diagnóstico , Fibrosis Pulmonar/mortalidad , Fibrosis Pulmonar/cirugía , Análisis de Regresión , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Ultrasonografía , Listas de Espera
17.
Ann Thorac Surg ; 92(4): 1226-31; discussion 1231-2, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21872213

RESUMEN

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is used occasionally as a bridge to lung transplantation. The impact on mid-term survival is unknown. We analyzed outcomes after lung transplant over a 19-year period in patients who received ECMO support. METHODS: From March 1991 to October 2010, 1,305 lung transplants were performed at our institution. Seventeen patients (1.3%) were supported with ECMO before lung transplant. Diagnoses included retransplantation (n = 6), pulmonary fibrosis (n = 6), cystic fibrosis (n = 4), and chronic obstructive pulmonary disease (n = 1). Fifteen patients underwent double lung transplant, one patient had single left lung transplant and one patient had a heart-lung transplant. Venovenous and venoarterial ECMO were implanted in eight and nine cases, respectively. Median duration of support was 3.2 days (range, 1 to 49 days). Mean patient follow-up was 2.3 years. RESULTS: Thirty-day, 1-year, and 3-year survivals were 81%, 74%, and 65%, respectively, for the supported patients and 93%, 78%, and 62% in the control group (p = 0.56). Two-year survival was not affected by ECMO type, with survival of five out of nine patients supported by venoarterial ECMO vs seven out of eight patients supported by venovenous ECMO (p = 0.17). At 1- year follow-up, allograft function for the ECMO-supported patients did not differ from the control group (forced expiratory volume in one second, 2.35 L vs 2.09 L, p = 0.39) (forced vital capacity, 3.06 L vs 2.71 L, p = 0.34). CONCLUSIONS: Extracorporeal membrane oxygenation as a bridge to lung transplantation is associated with higher perioperative mortality but acceptable mid-term survival in carefully selected patients. Late allograft function did not differ in patients who received ECMO support before lung transplant from those who did not receive ECMO.


Asunto(s)
Oxigenación por Membrana Extracorpórea/métodos , Trasplante de Pulmón/métodos , Cuidados Preoperatorios/métodos , Insuficiencia Respiratoria/terapia , Adulto , Estudios de Seguimiento , Supervivencia de Injerto , Trasplante de Corazón-Pulmón/métodos , Trasplante de Corazón-Pulmón/mortalidad , Humanos , Trasplante de Pulmón/mortalidad , Persona de Mediana Edad , Pennsylvania/epidemiología , Insuficiencia Respiratoria/mortalidad , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Factores de Tiempo , Trasplante Homólogo , Resultado del Tratamiento
18.
Ann Thorac Surg ; 92(6): 2125-31, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21982150

RESUMEN

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has been used to obtain rapid resuscitation and stabilization in advanced refractory cardiogenic shock (CS), but clear strategies to optimize outcomes and minimize futile support have not been established. METHODS: We retrospectively reviewed our experience with ECMO in patients with advanced refractory CS, after an acute myocardial infarct (AMI) compared with patients receiving ECMO after an acute decompensating chronic cardiomyopathy (CCM). RESULTS: Between January 2003 and February 2009, 33 patients required ECMO support for advanced refractory CS secondary to AMI (AMI-CS) and 9 patients were supported by ECMO in the presence of an acutely decompensated CCM (CCM-CS). Survival at 30 days, 1 and 2 years for patients with AMI-CS, was 64%, 48%, and 48% compared with 56%, 11%, and 11% at the same time points for those with CCM-CS (p = 0.05). In the AMI-CS group, 14 of 33 (42%) patients were weaned directly from ECMO after revascularization; 15 of 33 (45%) patients were bridged to ventricular assist device (VAD) support and subsequently either underwent heart transplantation (n = 6), were successfully weaned from VAD (n = 2) or died while on VAD support (n = 7). In the CCM-CS group, 7 patients were bridged to VAD support (77%), with 1 patient surviving after VAD weaning. CONCLUSIONS: Extracorporeal membrane oxygenation in advanced refractory AMI-CS is associated with acceptable outcomes in a well-selected population. The ECMO in patients with an acute decompensation of a chronic CM should be carefully considered, to avoid futile support.


Asunto(s)
Cardiomiopatías/complicaciones , Oxigenación por Membrana Extracorpórea , Infarto del Miocardio/complicaciones , Choque Cardiogénico/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Corazón Auxiliar , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Choque Cardiogénico/mortalidad
19.
J Heart Lung Transplant ; 30(7): 743-54, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21420318

RESUMEN

BACKGROUND: Induction therapy with alemtuzumab, followed by lower than conventional intensity post-transplant immunosuppression (eg, tacrolimus monotherapy), has been associated with reduced morbidity and mortality in abdominal and heart transplantation. We examined 5-year outcomes in lung recipients receiving alemtuzumab in conjunction with reduced-intensity post-transplant immunosuppression (early lower-dose tacrolimus; lower-dose steroids, with or without mycophenolate mofetil), compared with lung recipients receiving other induction agents or no induction in association with post-transplant immunosuppression. METHODS: A retrospective analysis was performed using prospectively collected data from a single-site clinical database of 336 lung recipients (aged ≥ 18) who received allografts between 1998 and 2005, classified by induction type: alemtuzumab, 127; Thymoglobulin, 43; daclizumab, 73; and none, 93. Survival analyses examined patient and graft survival, and freedom from acute cellular rejection (ACR), lymphocytic bronchiolitis, obliterative bronchiolitis (OB), bronchiolitis obliterans syndrome (BOS), and post-transplant lymphoproliferative disorder (PTLD). RESULTS: Five-year patient and graft survival differed by group (p = 0.046, p = 0.038, respectively). Alemtuzumab patient/graft survival rates were 59%/59%. Survival rates were 60%/44% for Thymoglobulin, 47%/46% for no induction, and 44%/41% for daclizumab. Freedom from ACR, lymphocytic bronchiolitis, OB, and BOS differed by group (all values, p < 0.008); alemtuzumab recipients showed greater 5-year freedom from each outcome (30%/82%/86%/54%) than Thymoglobulin (20%/54%/62%/27%), daclizumab (19%/55%/70%/43%), and no-induction groups (18%/70%/69%/46%). The groups did not differ in PTLD rates (≥ 94% free of PTLD at 5 years; p = 0.864). Effects were unchanged after controlling for potential covariates. CONCLUSIONS: Alemtuzumab induction may be associated with improved outcomes in lung transplantation. Randomized controlled trials are needed to establish any effects of this agent.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Antineoplásicos/uso terapéutico , Rechazo de Injerto/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Trasplante de Pulmón/métodos , Adulto , Alemtuzumab , Anticuerpos Monoclonales Humanizados , Suero Antilinfocítico/uso terapéutico , Bronquiolitis/etiología , Daclizumab , Femenino , Estudios de Seguimiento , Rechazo de Injerto/prevención & control , Supervivencia de Injerto , Humanos , Inmunoglobulina G/uso terapéutico , Trasplante de Pulmón/efectos adversos , Trasplante de Pulmón/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
20.
J Heart Lung Transplant ; 30(5): 523-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21239188

RESUMEN

BACKGROUND: Single-nucleotide polymorphisms (SNPs) associated with active cytomegalovirus (CMV) infections after lung transplantation have not been identified. METHODS: SNPs associated with varying levels of interferon (IFN)-γ (+874T/A), tumor necrosis factor-α (-308G/A), interleukin-10 (-1082G/A, -819C/T, -592C/A) and interleukin-6 (-174G/C) were characterized for 170 Caucasian lung transplant recipients who received alemtuzumab induction and valganciclovir prophylaxis against CMV. RESULTS: Patients were followed for a median of 34 months post-transplant, and 66% (113 of 170), 24% (40 of 170) and 10% (17 of 170) had no CMV infection, CMV viremia and CMV disease, respectively. Median times to CMV viremia and disease were 7 and 10 months, respectively. For each gene, there was no significant deviation from Hardy-Weinberg equilibrium. Independent risk factors for the development of CMV disease were IFN-γ +874 T/T genotype (associated with high levels of IFN-γ production), CMV donor-positive/recipient-negative (D(+)/R(-)) serostatus and acute cellular rejection requiring augmented immunosuppression (p = 0.001, 0.003 and 0.049, respectively). The association between IFN-γ +874 T/T genotype and CMV disease was most striking among R(+) patients (p = 0.02). D(+)/R(-) serostatus was also a significant risk factor for CMV viremia (p = 0.0005). IFN-γ +874 T/T genotype was associated with significantly lower peak CMV viral loads (p = 0.03). There were no associations between tumor necrosis factor-α, interleukin-10 or interleukin-6 SNPs and CMV infections. CONCLUSION: A genetic predisposition to elevated IFN-γ levels may play a dual role in controlling active CMV infection among lung transplant recipients receiving alemtuzumab induction and valganciclovir prophylaxis, limiting the extent of viral replication in serum but increasing the risk of CMV disease.


Asunto(s)
Infecciones por Citomegalovirus/epidemiología , Interferón gamma/genética , Trasplante de Pulmón , Polimorfismo de Nucleótido Simple/genética , Complicaciones Posoperatorias , Población Blanca/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alemtuzumab , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Anticuerpos Antineoplásicos/farmacología , Anticuerpos Antineoplásicos/uso terapéutico , Antivirales/farmacología , Antivirales/uso terapéutico , Biomarcadores/sangre , Citomegalovirus/fisiología , Infecciones por Citomegalovirus/sangre , Infecciones por Citomegalovirus/prevención & control , Femenino , Estudios de Seguimiento , Ganciclovir/análogos & derivados , Ganciclovir/farmacología , Ganciclovir/uso terapéutico , Humanos , Inmunosupresores/farmacología , Inmunosupresores/uso terapéutico , Interferón gamma/sangre , Interleucina-10/sangre , Interleucina-10/genética , Interleucina-6/sangre , Interleucina-6/genética , Trasplante de Pulmón/inmunología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/genética , Valganciclovir , Carga Viral , Replicación Viral/efectos de los fármacos , Replicación Viral/fisiología , Adulto Joven
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