Computational Requirements for Modeling Thermal Conduction in Polymeric Phase-Change Materials: Periodic Hard Spheres Case.

This research focuses on modeling heat transfer in heterogeneous media composed of stacked spheres of paraffin as a perspective polymeric phase-change material. The main goal is to study the requirements of the numerical scheme to correctly predict the thermal conductivity in a periodic system composed of an indefinitely repeated configuration of spherical particles subjected to a temperature gradient. Based on OpenFOAM, a simulation platform is created with which the resolution requirements for accurate heat transfer predictions were inferred systematically. The approach is illustrated for unit cells containing either a single sphere or a configuration of two spheres. Asymptotic convergence rates confirming the second-order accuracy of the method are established in case the grid is fine enough to have eight or more grid cells covering the distance of the diameter of a sphere. Configurations with two spheres can be created in which small gaps remain between these spheres. It was found that even the under-resolution of these small gaps does not yield inaccurate numerical solutions for the temperature field in the domain, as long as one adheres to using eight or more grid cells per sphere diameter. Overlapping and (barely) touching spheres in a configuration can be simulated with high fidelity and realistic computing costs. This study further extends to examine the effective thermal conductivity of the unit cell, particularly focusing on the volume fraction of paraffin in cases with unit cells containing a single sphere. Finally, we explore the dependence of the effective thermal conductivity for unit cells containing two spheres at different distances between them.

Validation of the Achievement Emotions Questionnaire for Experimental Science Education (AEQ-S).

The Achievement Emotions Questionnaire (AEQ), based on the control-value theory of achievement emotions, has been used in many fields of knowledge and has been translated into many languages. The main objective of this study was to adapt and validate it for the experimental sciences. A sample of 491 participants aged between 11 and 17 years (M = 13.73, SD = 1.19) from secondary schools in different localities in the provinces of Huelva and Lanzarote, Spain was used. The results obtained from the various statistical analyses showed that the questionnaire was valid and reliable. The main contribution of the work presented is to broaden the field of application of a test on emotions, AEQ-S, to experimental sciences. The AEQ-ES will allow us to learn the emotional profiles of students, thus providing information to teachers, and will be very useful for future research aimed at the study of emotions in experimental sciences.

Expression of the inflammasome components and its relationship with cardiovascular risk markers in people living with HIV-1 / Expresión de los componentes del inflamasoma y su relación con los marcadores de riesgo cardiovascular en personas con infección por HIV-1

Introduction: HIV-1 infection induces a chronic inflammatory state in which inflammasomes participate. The increase in inflammatory parameters is higher in individuals with active viral replication (progressors) than in those with viral control (HIV-1 controllers). This process triggers metabolic alterations related to changes in the lipid profile, which could increase the risk of cardiovascular events, even in patients with antiretroviral therapy. Objective: To establish whether there was a correlation between the expression of inflammasome components and cardiovascular risk markers in HIV-1 controllers and progressors with or without antiretroviral therapy. Materials and methods: We studied 13 HIV-1 controllers and 40 progressors (19 without antiretroviral therapy and 31 with therapy) and evaluated in them classic markers of cardiovascular risk. Using RT-PCR we quantified the expression of inflammasome components (NLRP1, NLRP3, NLRC4, AIM2, ASC, IL-1ß, IL-18, and caspase-1), TLR2, TLR4, TGF-ß, and IL-10. Results: Progressors with antiretroviral therapy had an increased expression of TLR2, TLR4, and IL-18 compared to HIV-1 controllers. They also showed high levels of triglycerides and VLDL, which positively correlated with the expression of the inflammasome components NLRP1, NLRP3, NLRC4, AIM2, ASC, and caspase-1. Conclusion: Progressors receiving antiretroviral therapy exhibited an increased expression of the inflammasome components, which correlated with the levels of triglycerides and VLDL. This supports the role of inflammation in cardiovascular risk during HIV-1 infection.

Introducción. La infección por el HIV-1 induce un estado de inflamación crónico en el que participan los inflamasomas. El incremento de los parámetros inflamatorios es mayor en individuos con replicación viral activa que en aquellos con control de la replicación viral. Este proceso desencadena alteraciones metabólicas relacionadas con cambios en el perfil lipídico, lo cual podría incrementar el riesgo de eventos cardiovasculares, incluso en pacientes con terapia antirretroviral. Objetivo. Establecer si existe correlación entre la expresión de los componentes de los inflamasomas y los marcadores de riesgo cardiovascular en individuos con control de la replicación viral y en aquellos con replicación viral activa con terapia antirretroviral o sin ella. Materiales y métodos. Se estudiaron 13 individuos con control de la replicación viral y 40 con replicación viral activa (19 sin terapia antirretroviral y 31 con terapia). Se evaluaron los marcadores clásicos de riesgo cardiovascular y se cuantificó mediante RT-PCR la expresión de los componentes de los inflamasomas (NLRP1, NLRP3, NLRC4, AIM2, ASC, IL-1ß, IL-18 y caspasa-1), TLR2, TLR4, TGF-ß e IL-10. Resultados. Se observó que los pacientes con replicación viral activa y con terapia antirretroviral presentaron un incremento en la expresión de TLR2, TLR4 e IL-18, comparados con los controladores del HIV-1. Además, mostraron grandes valores de triglicéridos y lipoproteína de muy baja densidad (Very Low Density Lipopretein, VLDL), lo que se correlaciona positivamente con la expresión de los componentes de los inflamasomas NLRP1, NLRP3, NLRC4, AIM2, ASC y caspasa-1. Conclusión. El aumento en la expresión de los componentes de los inflamasomas en los individuos con replicación viral activa y con terapia antirretroviral se correlacionó con las concentraciones de triglicéridos y VLDL, lo que sugiere el papel de la activación inmunitaria y la terapia antirretroviral en el riesgo cardiovascular.

Predicting Substance Use from Religiosity/Spirituality in Individuals with Cystic Fibrosis.

Religiosity and spirituality predict lower alcohol and other substance use in community samples of adolescents and adults. However, the roles of religiosity and spirituality in substance use have not been examined in individuals with cystic fibrosis (CF). Adults with CF (n = 123) completed measures of spirituality, religiosity, and substance use. Clinical measures of illness severity (e.g., BMI and  %FEV1) were obtained from participants' medical records. Substance use rates for alcohol, tobacco, and marijuana were lower in this sample than those seen in the general population. Of the measured BMMRS subscales, spiritual experiences and religious commitment were significant predictors of lower alcohol use. These results suggest that personal factors of religiosity and spirituality are more important for substance use in adults with CF than participation in religious service and events or adoption of religious practices.

Reciprocal Links Between Physical Health and Coping Among Adolescents With Cystic Fibrosis.

OBJECTIVE: Adolescents with cystic fibrosis (CF) often face a unique set of difficulties and challenges as they transition to adulthood and autonomy while also managing a progressive illness with a heavy treatment burden. Coping styles have been related to changes in physical health among youth with chronic illness more generally, but the directionality of these links has not been fully elucidated. Therefore, the objective of this study was to evaluate bidirectional links between coping styles and physical health indicators among adolescents with CF over time. METHODS: Adolescents (N = 79, 54% female) recruited from inpatient and outpatient CF clinics at two sites completed questionnaires assessing secular and religious/spiritual coping styles at two time points (18 months apart, on average). Health indicators including pulmonary functioning, nutritional status, and days hospitalized were obtained from medical records. RESULTS: More frequent hospitalizations predicted lower levels of adaptive secular coping over time. However, poorer pulmonary functioning predicted higher levels of positive religious/spiritual coping. The number of days hospitalized was related to adaptive secular coping and negative religious/spiritual coping. CONCLUSIONS: Among youth with CF, physical health functioning is more consistent in predicting coping strategies than the reverse. Poorer pulmonary functioning appears to enhance adaptive coping over time, suggesting resilience of adolescents with CF, while more frequent hospitalizations may inhibit the use of adaptive coping strategies. Findings support the use of interventions aimed at promoting healthy coping among hospitalized adolescents with CF.

Religious coping and psychosocial adjustment in patients with cystic fibrosis.

The role of religious coping (RC) in psychosocial outcomes and health-related quality of life (HRQoL) in adults with cystic fibrosis has not been addressed. Multivariate regressions evaluated the effects of baseline RC on depressive and anxiety symptoms and HRQoL at 3-month follow-up in 123 adult cystic fibrosis patients. Higher positive RC attenuated the effects of perceived stress on greater depressive and anxiety symptoms. Negative RC predicted less vitality and social HRQoL, as well as more digestion symptoms. Positive RC may buffer the impact of stress on patients' psychological distress, whereas negative RC may contribute to lower health-related quality of life.

Evaluation of Differences in Metabolic and Immunologic Markers and Cardiovascular Risk in HIV-1 Patients / Evaluación de la relación entre marcadores metabólicos, inmunológicos y de riesgo cardiovascular en pacientes con VIH-1 / Avaliação da relação entre marcadores metabólicos, imunológicos e de risco cardiovascular em pacientes com HIV-1

Introduction:hiv infection induces an exacerbated chronic inflammatory response, which triggers met-abolic disorders and cardiovascular diseases; however, there are individuals, known as hiv controllers, who do not have typical progression markers. As cardiovascular risk tests are not accurate on hiv-1 infected patients, the study of metabolic and inflammatory parameters in individuals with different patterns of progression could contribute to the definition of predictors of cardiovascular disease in this population. The aim of this study was to compare hiv controllers and hiv progressors (with and without antiretroviral therapy) as well as with healthy controls in order to explore differences and correlations in metabolic and inflammatory biomarkers associated with cardiovascular risk. Materials and methods:This was a cross-sectional analytical study which included 63 individuals infected with hiv-1 classified as hiv controllers or progressors (with or without antiretroviral therapy), and a healthy control group. The following parameters were determined: carotid intima-media thickness (cimt); cardiovascular risk scores; lipid profile, fasting glucose, high-sensitivity crp, D-dimer, sCD14, sCD163, il-6, and il-18. Data were compared with Anova or Kruskal­Wallis, and correlations were evaluated by the Spearman coef-ficient. Results: While there were no significant differences in Framingham, dad or cimt values, hiv con-trollers exhibited lower triglycerides levels when compared with hiv progressors. No differences were observed in markers, such as high-sensitivity crp, il-6, il-18, and sCD163, among the groups. The median hdl value was higher in hiv progressors on antiretroviral therapy, and cimt in hiv controllers was nega-tively correlated with sCD14. Conclusion:hiv controllers have a different cardiovascular profile than hivprogressors according to their values in metabolic and immunological biomarkers

Introducción: la infección por vih-1 induce una respuesta inflamatoria crónica exacerbada que desencadena alteraciones metabólicas y cardiovasculares; sin embargo, algunos individuos "controladores" no presentan los marcadores de progresión típicos. Dado que las pruebas que evaluan el riesgo cardiovascular carecen de precisión en pacientes con vih-1, el estudio de parámetros inflamatorios en individuos con diferente progresión podría aportar a la definición de predictores de enfermedad cardiovascular en esta población. El objetivo es explorar diferencias y correlaciones en biomarcadores metabólicos e inflamatorios asociados con riesgo cardiovascular, comparando individuos controladores y progresores con y sin terapia antiviral. Materiales y métodos: estudio analítico transversal con 63 individuos infectados por vih-1, clasificados en controladores y progresores (con terapia antiviral y sin esta), y controles sanos. Se midió el grosor de la íntima media carotidea (cimt), puntajes de riesgo cardiovascular y cuantificación de perfil lipídico, glucemia en ayunas, pcr ultrasensible, dímero D, sCD14, sCD163, il-6 e il-18. Se realizó comparación por Anova o Kruskal-Wallis y correlación por coeficiente de Spearman. Resultados: no hubo diferencias significativas en índices de Framingham, dad o cimt, pero los individuos controladores presen-taron menores valores de triglicéridos, comparados con los progresores. No se observaron diferencias en pcr ultrasensible, il-6, il-18, y sCD163, entre los grupos estudiados. La mediana del hdl fue mayor en los progresores con terapia antiviral y el cimt en los controladores se correlacionó negativamente con sCD14. Conclusión: los individuos controladores presentan un perfil cardiovascular diferente a los individuos progresores, de acuerdo con los biomarcadores metabólicos e inmunológicos evaluados

Introdução: a infecção pelo hiv-1 induz resposta inflamatória crônica exacerbada, que desencadeia alte-rações metabólicas e doenças cardiovasculares; no entanto, existem indivíduos, chamados controlado-res, que não possuem os marcadores de progressão típicos. Tendo em vista que os testes que avaliam o risco cardiovascular carecem de precisão em pacientes com hiv-1, o estudo de parâmetros metabólicos e inflamatórios em indivíduos com diferentes padrões de progressão pode contribuir para a definição de preditores de doença cardiovascular nessa população. O objetivo é explorar diferenças e correlações em biomarcadores metabólicos e inflamatórios associados ao risco cardiovascular, comparando indiví-duos controladores e progressores submetidos ou não à terapia antiviral. Materiais e métodos: Estudo analítico transversal que incluiu 63 indivíduos infectados pelo hiv-1, classificados como controladores e progressores (com e sem terapia antiviral), além de grupos controle saudáveis. Realizou-se a medição da espessura da íntima média da carótida (cimt), pontuações de risco cardiovascular; e quantificação do perfil lipídico, glicemia em jejum, pcr ultrassensível, dímero d, sCD14, sCD163, il-6 e il-18. A comparação foi feita por Anova ou teste de Kruskal-Wallis e a correlação pelo coeficiente de Spearman. Resultados.Embora não tenha havido diferenças significativas nos índices de Framingham, dad ou cimt, os indivíduos controladores apresentaram valores de triglicerídeos mais baixos, em comparação com os progressores. Não foram observadas diferenças em marcadores como pcr ultrassensível, il-6, il-18 e sCD163, entre os grupos estudados. O hdl médio foi maior em indivíduos progressores em terapia antiviral, e o cimtem indivíduos controladores foi negativamente correlacionado com o sCD14. Conclusão: os indivíduos controladores apresentam um perfil cardiovascular diferente dos indivíduos progressores, de acordo com os biomarcadores metabólicos e imunológicos avaliados

Implementation of a successful eradication protocol for Burkholderia Cepacia complex in cystic fibrosis patients.

BACKGROUND: Infection with Burkholderia cepacia complex (Bcc) results in a heterogeneous clinical course ranging from asymptomatic colonization of the airways to fulminant respiratory failure in patients with cystic fibrosis (CF). Early eradication of Pseudomonas aeruginosa improves clinical outcomes. The efficacy and clinical outcomes following implementation of an eradication protocol for Bcc are less well understood. METHODS: We developed and implemented a single center Bcc eradication protocol that included an intensive combination of intravenous, inhaled, and oral antibiotic therapies based on in vitro sensitivities. We conducted a retrospective cohort analysis of clinical outcomes compared to patients with chronic Bcc infection. RESULTS: Six patients were identified as having a newly acquired Bcc colonization and were placed on the eradication protocol. Sequential sputum samples after completion of the protocol demonstrated sustained clearance of Bcc in all patients. Lung function and nutritional status remained stable in the year following eradication. CONCLUSION: Clearance of Bcc from sputum cultures using a standardized protocol was successful at one year and was associated with clinical stability.

Interprofessional simulation training improves knowledge and teamwork in nursing and medical students during internal medicine clerkship.

Simulation is effective at improving healthcare students' knowledge and communication. Despite increasingly interprofessional approaches to medicine, most studies demonstrate these effects in isolation. We enhanced an existing internal medicine curriculum with immersive interprofessional simulations. For ten months, third-year medical students and senior nursing students were recruited for four, 1-hour simulations. Scenarios included myocardial infarction, pancreatitis/hyperkalemia, upper gastrointestinal bleed, and chronic obstructive pulmonary disease exacerbation. After each scenario, experts in medicine, nursing, simulation, and adult learning facilitated a debriefing. Study measures included pre- and post-tests assessing self-efficacy, communication skills, and understanding of each profession's role. Seventy-two medical students and 30 nursing students participated. Self-efficacy communication scores improved for both (medicine, 18.9 ± 3.3 pretest vs 23.7 ± 3.7 post-test; nursing, 19.6 ± 2.7 pretest vs 24.5 ± 2.5 post-test). Both groups showed improvement in "confidence to correct another healthcare provider in a collaborative manner" (Δ = .97 medicine, Δ = 1.2 nursing). Medical students showed the most improvement in "confidence to close the loop in patient care" (Δ = .93). Nursing students showed the most improvement in "confidence to figure out roles" (Δ = 1.1). This study supports the hypothesis that interdisciplinary simulation improves each discipline's self-efficacy communication skills and understanding of each profession's role. Despite many barriers to interprofessional simulation, this model is being sustained.

Extensive surgical and comprehensive postoperative medical management for cystic fibrosis chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis has a major impact on the quality of life of patients with cystic fibrosis (CF) and may contribute to progression of chronic lung disease. Despite multiple sinus surgeries, maxillary sinus involvement is a recurrent problem. The modified endoscopic medial maxillectomy (MEMM) permits debridement in the clinic, improves mucus clearance with nasal irrigations, and increases access for topical delivery of therapeutics. However, clinical outcomes of aggressive sinus surgery with regimented postoperative medical treatment have not been systematically evaluated. METHODS: CF patients completed the 22-Item Sinonasal Outcome Test questionnaires before sinus surgery (and bilateral MEMM) and at sequential postoperative visits. Objective measures included Lund-Kennedy endoscopic score and pulmonary function tests (forced expiratory volume at 1 second percent [FEV(1)%] predicted). Culture-directed antibiotic therapy, prednisone, and topical irrigations were initiated postoperatively. RESULTS: Twenty-two patients (mean age, 26.5 years; 4.9 prior sinus operations) underwent MEMM and sinus surgery. Symptom scores were significantly reduced at 60 days (primary outcome, 64.7 ± 18.4 presurgery versus 27.5 ± 15.3 postsurgery; p < 0.0001) and up to a year postoperatively (27.6 ± 12.6; p < 0.0001). Endoscopic scores were also reduced after surgery (10.4 ± 1.1 presurgery versus 5.7 ± 2.4 [30 days], 5.7 ± 1.4 [60 days], 5.8 ± 1.3 [120 days], and 6.0 ± 1.1 [1 year]; p < 0.0001)]. There were no differences in FEV(1)% predicted up to 1 year postoperatively, but hospital admissions secondary to pulmonary exacerbations significantly decreased (2.0 ± 1.4 versus 3.2 ± 2.4, respectively; p < 0.05). CONCLUSION: Prospective evaluation indicates sinus surgery with MEMM is associated with marked improvement in sinus disease outcomes. Additional studies are necessary to confirm whether this treatment paradigm is associated with improved CF pulmonary disease.

Salvaging the dehisced lung transplant bronchial anastomosis with homograft aorta.

This is a case of 50-year-old male who underwent left single lung transplantation for pulmonary fibrosis. He sustained a bronchial dehiscence with a pulmonary artery-bronchial fistula which was primarily repaired. One week later, there was complete bronchial dehiscence followed by a massive hemoptysis. At operation, following resection of necrotic donor bronchus there was a sizeable gap between donor and recipient bronchus, which was bridged with a cryopreserved aortic homograft. The homograft patch provided a satisfactory repair without malacia. The patient required retransplantation six months later for reasons unassociated with the repair. Homograft aorta proved useful material for salvaging the dehisced lung transplant bronchial anastomosis.

Polymorphisms in fatty acid binding protein 5 show association with type 2 diabetes.

Genes for the fatty acid binding proteins (FABP) family encode small 14-15 kDa cytosolic proteins and can be regulated during type 2 diabetes mellitus (T2DM) and obesity. This study compared association of single nucleotide polymorphisms (SNPs) in FABP1-5 with T2DM in different ethnic groups. Associations with T2DM of SNPs in these proteins were assessed in African American (AA), non-Hispanic White (NHW), and Hispanic American (HA) individuals. A total of 650 DNA samples were genotyped; control samples were obtained from Coriell's North American Human Variation Panel Repository (NAHVP) of apparently healthy individuals and T2DM cases were taken from the American Diabetes Association GENNID Study. The rs454550 SNP of FABP5 showed a significant association with T2DM in NHW (OR: 9.03, 95% CI: 1.13-71.73, p=0.014). Our analysis also identified a new FABP5 SNP (nSNP) that showed a significant association with T2DM in NHW (OR: 0.44, 95% CI: 0.19-0.99, p=0.045) and AA (OR: 0.17, 95% CI: 0.03-0.80, p=0.016). The Ala54Thr FABP2 polymorphism was significantly associated with T2DM in HA individuals only (OR: 1.85, 95% CI: 1.05-3.27, p=0.032). All other FABP SNPs did not show association with T2DM. These findings suggest a potential distinct role(s) of SNPs in FABP5 and FABP2 genes in T2DM in different populations.

Microbiology, safety, and pharmacokinetics of aztreonam lysinate for inhalation in patients with cystic fibrosis.

BACKGROUND: Aztreonam lysinate for inhalation (AI) is a novel monobactam formulation being investigated for pulmonary Pseudomonas aeruginosa infections in patients with cystic fibrosis (CF). METHODS: Pre-clinical studies investigated the pre- and post-nebulization activity of AI and its activity in the presence of CF sputum. A double-blind, placebo-controlled, dose-escalation trial determined pharmacokinetics and tolerability of AI in subjects with CF. Single daily escalating doses of AI 75, 150, or 225 mg, or placebo were self-administered using an eFlow Electronic Nebulizer. Sputum samples were collected up to 4 hr and blood samples up to 8 hr post-dose. RESULTS: AI activity against multiple CF isolates was retained after nebulization via eFlow, and activity was not inhibited by CF sputum. All 12 adult subjects and 11/12 adolescents tolerated all AI doses. One patient had an asymptomatic FEV1 decrease > 20% with the 150 mg dose. Median aztreonam sputum concentrations in adults 10 min after AI 75, 150, and 225 mg were 383, 879, and 985 microg/g, respectively. Median sputum concentrations in adolescents 10 min after AI 75, 150, and 225 mg were 324, 387, and 260 microg/g, respectively. Systemic exposure to AI was low. Plasma pharmacokinetics in adults receiving AI 75 mg were Cmax = 419 ng/g, Tmax = 0.99 hr, t1/2 = 2.1 hr. Aztreonam concentrations in sputum were at or above the MIC50 for at least 4 hr post-dose. CONCLUSION: These data support the continued development of AI for treatment of pulmonary infections in patients with CF.

Multi-organ transplantation: is there a protective effect against acute and chronic rejection?

BACKGROUND: Heart-lung transplantation (Tx) is known to offer a protective effect against acute cardiac rejection. This study was undertaken to evaluate acute and chronic heart and/or lung rejection in the setting of multiple-transplanted organs from the same donor compared with single-organ transplantation. METHODS: Acute (treated rejection episodes of heart or lungs) and chronic (allograft vasculopathy in hearts and bronchiolitis obliterans syndrome [BOS] in lungs) rejection events were analyzed in 348 heart transplant (H) recipients, 24 heart-lung (HL) recipients, 82 double-lung (L) recipients and 8 heart-kidney (HK) recipients >18 years of age, who were transplanted between 1990 and 2002. RESULTS: Survival at 3 years differed among groups as follows: HK, 100%; H, 82%; HL, 74%; and L, 70%. The probability of acute rejection within the first 3 months was higher in H recipients than in HL (81% vs 22%; p < 0.0001) or HK (81% vs 12%; p = 0.00009) recipients. Acute cardiac rejection occurred more frequently during the first 2 years in isolated H recipients compared with HL (2.8 vs 0.27 episodes; p < 0.0001) and HK (2.8 vs 0.54; p < 0.001) recipients. Acute lung rejection occurred more frequently in the first 2 years in L than HL (2.4 vs 1.0 episodes; p = 0.02) recipients. Chronic cardiac rejection (allograft vasculopathy) was more likely within 3 years after H compared with HL (32% vs 16%; p = 0.04) or HK (32% vs 0%; p = 0.14). The onset of chronic lung rejection (BOS) within 3 years was similar in HL and L recipients (39% vs 40%; p = 0.9). CONCLUSIONS: Recipients of multiple organs from a single donor undergo less acute rejection of the heart or lungs compared with isolated heart or lung transplant recipients. Cardiac allograft vasculopathy is decreased significantly when cardiac transplantation is combined with a lung allograft. A lower incidence of cardiac allograft vasculopathy is observed when cardiac transplantation is combined with a renal allograft, and may prove statistically significant when more cases have been accumulated. These phenomena may result from immune modulation of the recipient by simultaneous transplant of disparate tissues or introduction of immune-modulating hematopoietic elements.

The intensive care unit oxygen challenge should not be used for donor lung function decision-making.

BACKGROUND: The intensive care unit oxygen challenge is a routine screening test for donor lung function. An arterial PO2 of <300 mm Hg is generally considered evidence of inadequate pulmonary function that contraindicates the use of the lungs for transplantation. METHODS: Between December 1, 2001 and January 24, 2004, the intensive care unit oxygen challenge was compared with the PO2 in samples drawn from each pulmonary vein confluence in the operating room in 91 donors (182 donor lungs) after the lungs were fully inflated (FIO2 1.0). There were 62 males and 29 females, with a median age of 27.5 years (13.6 to 55.4 years). RESULTS: In 40 lungs, the pulmonary vein PO2 was >300 mm Hg, whereas the PO2 was <300 mm Hg on the last intensive care unit O2 challenge. The difference between the intensive care unit PO2 and the operating room pulmonary vein PO2 was greatest for donors with the lowest intensive care unit PO2. Of these 40 lungs, 8 were transplanted, all of whom had excellent graft function with a median intubation of 14.2 hours (6.1 to 23.8 hours). No patient sustained primary graft failure or an airway complication. CONCLUSIONS: The intensive care unit PO2 is an unreliable screening test for donor lung function, particularly when one lung is clear and the other is unclear radiographically. In this setting, intraoperative surgical assessment and pulmonary venous PO2 should be the basis for determining donor lung suitability. This strategy may provide an opportunity to increase donor lung availability.