RESUMO
OBJECTIVES: Prolonged pleural effusion/chylothorax (PPE/C) is a less investigated complication following paediatric cardiac surgery, and its true incidence, risk factors and impact on postoperative outcomes are not well described. We aim to address these gaps in knowledge using data from a prospective, multicentre study. METHODS: Data on 9 post-operative morbidities (unplanned reinterventions, extracorporeal life support, necrotising enterocolitis, PPE/C, renal replacement therapy, major adverse events, acute neurological events, feeding issues and postsurgical infection) were prospectively collected at 5 UK centres between 2015 and 2017, following paediatric cardiac surgery. Incidence of PPE/C, associations with procedure types, and risk factors were described. Mortality (30-day and 6-month) and hospital length of stay (HLoS) were compared between those with isolated PPE/C, single non-PPE/C morbidity, no morbidity, multimorbidity PPE/C and non-PPE/C multimorbidity. RESULTS: A total of 3090 procedures (2861 patients) were included (median age, 228 days). There were 202 PPE/C (incidence of 6.5%), occurring at a median of 6 days postoperatively (interquartile range: 3-10). PPE/C was associated with excess early mortality only when complicating scenarios where at least 2 other post-operative morbidities occurred. On average PPE/C is associated with 8 more HLoS days, but the relative impact is greatest when comparing isolated PPE/C with no morbidity (P < 0.001), whereas in multimorbidity scenarios, PPE/C does not significantly contribute to an increase of HLoS. CONCLUSIONS: Addition of PPE/C increases mortality but not HLoS in multimorbidity and HLoS only in single morbidity scenarios. This reinforces the important role of prevention, early detection and management of PPE/C in complex situations.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Quilotórax , Derrame Pleural , Complicações Pós-Operatórias , Humanos , Masculino , Fatores de Risco , Feminino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Lactente , Derrame Pleural/epidemiologia , Derrame Pleural/etiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Estudos Prospectivos , Pré-Escolar , Quilotórax/epidemiologia , Quilotórax/etiologia , Incidência , Recém-Nascido , Criança , Tempo de Internação/estatística & dados numéricos , Reino Unido/epidemiologiaRESUMO
OBJECTIVES: Children with CHD are at heightened risk of neurodevelopmental problems; however, the contribution of acute neurological events specifically linked to the perioperative period is unclear. AIMS: This secondary analysis aimed to quantify the incidence of acute neurological events in a UK paediatric cardiac surgery population, identify risk factors, and assess how acute neurological events impacted the early post-operative pathway. METHODS: Post-operative data were collected prospectively on 3090 consecutive cardiac surgeries between October 2015 and June 2017 in 5 centres. The primary outcome of analysis was acute neurological event, with secondary outcomes of 6-month survival and post-operative length of stay. Patient and procedure-related variables were described, and risk factors were statistically explored with logistic regression. RESULTS: Incidence of acute neurological events after paediatric cardiac surgery in our population occurred in 66 of 3090 (2.1%) consecutive cardiac operations. 52 events occurred with other morbidities including renal failure (21), re-operation (20), cardiac arrest (20), and extracorporeal life support (18). Independent risk factors for occurrence of acute neurological events were CHD complexity 1.9 (1.1-3.2), p = 0.025, longer operation times 2.7 (1.6-4.8), p < 0.0001, and urgent surgery 3.4 (1.8-6.3), p < 0.0001. Unadjusted comparison found that acute neurological event was linked to prolonged post-operative hospital stay (median 35 versus 9 days) and poorer 6-month survival (OR 13.0, 95% CI 7.2-23.8). CONCLUSION: Ascertainment of acute neurological events relates to local measurement policies and was rare in our population. The occurrence of acute neurological events remains a suitable post-operative metric to follow for quality assurance purposes.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Complicações Pós-Operatórias , Humanos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Feminino , Masculino , Estudos Prospectivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Lactente , Fatores de Risco , Pré-Escolar , Incidência , Cardiopatias Congênitas/cirurgia , Criança , Tempo de Internação/estatística & dados numéricos , Reino Unido/epidemiologia , Recém-Nascido , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/epidemiologiaRESUMO
We previously selected and defined nine important post-operative morbidities linked to paediatric cardiac surgery, and prospectively measured their incidence following 3090 consecutive operations. Our aim was to study the impact of these morbidities on family functioning and parental quality of life over 6 months in a subset of cases. As part of a prospective case matched study in five of the ten children's cardiac centers in the UK, we compared outcomes for parents of children who had a 'single morbidity', 'multiple morbidities', 'extracorporeal life support (ECLS)' or 'no morbidity'. Outcomes were evaluated using the PedsQL Family impact module (FIM) at 6 weeks and 6 months post-surgery. Outcomes were modelled using mixed effects regression, with adjustment for case mix and clustering within centers. We recruited 340 patients with morbidity (60% of eligible patients) and 326 with no morbidity over 21 months. In comparison to the reference group of 'no morbidity', after adjustment for case mix, at 6 weeks parent health-related quality of life (HRQoL) and total FIM sores were lower (worse) only for ECLS (p < 0.005), although a higher proportion of parents in both the ECLS and multi-morbidity groups had low/very low scores (p < .05). At 6 months, parent outcomes had improved for all groups but parent HRQoL and total score for ECLS remained lower than the 'no morbidity' group (p < .05) and a higher proportion of families had low or very low scores in the ECLS (70%) group (p < .01). Post-operative morbidities impact parent HRQoL and aspects of family functioning early after surgery, with this impact lessening by 6 months. Families of children who experience post-operative morbidities should be offered timely psychological support.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Qualidade de Vida , Criança , Humanos , Qualidade de Vida/psicologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Morbidade , Pais/psicologia , Incidência , Inquéritos e QuestionáriosRESUMO
OBJECTIVES: To explore whether postoperative morbidities after pediatric cardiac surgery affected children's health-related quality of life (HRQOL) at 6 months, through potentially modifiable parental psychological factors. DESIGN: We undertook a mediation analysis, to explore the causal pathway, based on data from a prospective, case-matched cohort study. PATIENTS: Six hundred sixty-six children undergoing cardiac surgery. SETTING: Five centers in the United Kingdom. INTERVENTIONS: No intervention. MEASUREMENTS AND MAIN RESULTS: Cases of morbidity were identified early after pediatric cardiac surgery, and matched controls with no morbidities were identified at discharge. Four mediators were assessed at 6 weeks after surgery, using the PedsQL Family Impact Module (Parent HRQOL and Family Function) and the PHQ-4 (Anxiety and Depression). The study outcome of child HRQOL was assessed at 6 months with the PedsQL. Of 666 children, 408 (65% of those surviving) contributed to the primary outcome. Children who had extracorporeal life support (ECLS) ( n = 11) ( p < 0.05) and multiple morbidities ( n = 62) ( p < 0.01) had worse 6-month HRQOL than those with a single morbidity ( n = 125) or no morbidity ( n = 209). After adjustment for case mix complexity and sociodemographic variables, there were significant indirect effects of parent HRQOL at 6 weeks, on the PedsQL Total Score (ECLS, -5.1 [-8.4 to -1.8]; p = 0.003; multiple morbidities, -2.1 [-3.7 to -0.5]; p = 0.01), PedsQL Physical Score (ECLS, -5.1 [-8.7 to -1.4]; p = 0.007; multiple morbidities, -2.1 [-3.8 to -0.4]; p = 0.016), and PedsQL Psychosocial Score (ECLS: -5.3 [-8.7 to -1.8); p = 0.003; multiple morbidities, -2.2 [-3.9 to -0.5]; p = 0.01). The proportion of the total effect of ECLS and multiple morbidity on the study outcomes mediated through parent HRQOL ranges between 18% and 61%. There was no evidence that the other three mediators had indirect effects on the study outcome. CONCLUSIONS: Parental HRQOL at 6 weeks after surgery contributes to child HRQOL at 6 months, among those with the severest types of morbidity, and as such should be a target for future interventions.
Assuntos
Análise de Mediação , Qualidade de Vida , Criança , Humanos , Qualidade de Vida/psicologia , Estudos de Coortes , Estudos Prospectivos , Pais/psicologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Inquéritos e QuestionáriosRESUMO
New tools are needed to support pre-exposure prophylaxis (PrEP) adherence for human immunodeficiency virus (HIV) prevention, including those that enable real-time feedback. In a large, completed PrEP trial, adequate urine tenofovir levels measured using a novel immunoassay predicted HIV protection and showed good sensitivity and specificity for detectable plasma tenofovir.
Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Fármacos Anti-HIV/uso terapêutico , Emtricitabina/uso terapêutico , HIV , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Imunoensaio , Adesão à Medicação , Tenofovir/uso terapêuticoRESUMO
OBJECTIVE: Unplanned reintervention (uRE) is used as an indicator of patient morbidity and quality of care in pediatric cardiac surgery. We investigated associated factors and early mortality after uREs. METHODS: Morbidity data were prospectively collected in 5 UK centers between 2015 and 2017; uRE included surgical cardiac, interventional transcatheter cardiac, permanent pacemaker, and diaphragm plication procedures. Mortality (30-day and 6-month) in uRE/no-uRE patients was reported before and after matching. Predicted 30-day mortality was calculated using the Partial Risk Adjustment in Surgery score. RESULTS: A total of 3090 procedures (2861 patients) were included (median age, 228 days). There were 146 uREs, resulting in an uRE rate of 4.7%. Partial Risk Adjustment in Surgery score, 30-day mortality and 6-month mortality in uRE and no-uRE groups were 2.4% versus 1.3%, 8.9% versus 1%, and 17.1% versus 2.4%, respectively. After matching, mortality at 6 months remained higher in uRE compared with no-uRE (12.2% vs 1.4%; P = .02; 74 pairs). In the uRE group, 21 out of 25 deaths at 6 months occurred when at least 1 additional postoperative complication was present. In multivariable analysis, neonatal age (P = .002), low weight (P = .009), univentricular heart (P < .001), and arterial shunt (P < .001) were associated with increased risk of uRE, but Partial Risk Adjustment in Surgery score was not (only in univariable analysis). CONCLUSIONS: uREs are a relatively frequent complication after pediatric cardiac surgery and are associated with some patient characteristics, but not the Partial Risk Adjustment in Surgery risk score. Early mortality was higher after uRE, independent of preoperative factors, but linked to other postoperative complications.
Assuntos
Procedimentos Cirúrgicos Cardíacos/mortalidade , Cardiopatias Congênitas/cirurgia , Complicações Pós-Operatórias/cirurgia , Reoperação/mortalidade , Adolescente , Fatores Etários , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/mortalidade , Humanos , Lactente , Recém-Nascido , Masculino , Complicações Pós-Operatórias/mortalidade , Estudos Prospectivos , Indicadores de Qualidade em Assistência à Saúde , Reoperação/efeitos adversos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Reino UnidoRESUMO
BACKGROUND: Most children now survive cardiac surgery, and the focus of quality improvement initiatives has shifted toward more complex outcome measures. The aim of this investigation was to study the impact of early postoperative morbidities on parent-reported patient quality of life and parental anxiety or depression over 6 months. METHODS: This prospective case-matched cohort study was conducted in 5 UK children's cardiac centers. Measures of impact for patient categories of "single morbidity," "multiple morbidities," and "extracorporeal life support (ECLS)" were compared with "no morbidity." The measures used were the Pediatric Quality of Life Inventory (PedsQL) and the 4-item Patient Health Questionnaire (PHQ-4) at 6 weeks and 6 months postoperatively. The study modeled the outcomes using mixed effects regression, adjusting for case mix and clustering within centers. RESULTS: The study included 666 patients who underwent operation at a median age of 81 days (interquartile range, 10 to 325 days). At 6-week follow-up, significant adjusted differences to the reference group with no morbidity were found for total PedsQL scores, which were lower in patients with ECLS (P = .01), multiple morbidities (P < .001), and a single morbidity (P = .04), as well as the proportion of parents with anxiety and depression, which were higher in the group with multiple morbidities (P = .04 and P = .01, respectively). At 6 months, measures had improved in all morbidity groups. The only significant adjusted difference in the reference group was for physical PedsQL scores in ECLS (P = .04) and multiple morbidities (P < .01). CONCLUSIONS: Patient and parent well-being are strongly influenced by postoperative morbidities early after surgery, with improvement by 6 months. Family psychological support and holistic rehabilitation are vital for children who experience postoperative morbidities.
Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Saúde Mental , Pais/psicologia , Complicações Pós-Operatórias/epidemiologia , Qualidade de Vida , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Morbidade/tendências , Complicações Pós-Operatórias/psicologia , Período Pós-Operatório , Estudos Prospectivos , Reino Unido/epidemiologiaRESUMO
OBJECTIVE: Early mortality rates for paediatric cardiac surgery have fallen due to advancements in care. Alternative indicators of care quality are needed. Postoperative morbidities are of particular interest. However, while health impacts have been reported, associated costs are unknown. Our objective was to calculate the costs of postoperative morbidities following paediatric cardiac surgery. DESIGN: Two methods of data collection were integrated into the main study: (1) case-matched cohort study of children with and without predetermined morbidities; (2) incidence rates of morbidity, measured prospectively. SETTING: Five specialist paediatric cardiac surgery centres, accounting for half of UK patients. PATIENTS: Cohort study included 666 children (340 with morbidities). Incidence rates were measured in 3090 consecutive procedures. METHODS: Risk-adjusted regression modelling to determine marginal effects of morbidities on per-patient costs. Calculation of costs for hospital providers according to incidence rates. Extrapolation using mandatory audit data to report annual financial burden for the health service. OUTCOME MEASURES: Impact of postoperative morbidities on per-patient costs, hospital costs and UK health service costs. RESULTS: Seven of the 10 morbidity categories resulted in significant costs, with mean (95% CI) additional costs ranging from £7483 (£3-£17 289) to £66 784 (£40 609-£103 539) per patient. On average all morbidities combined increased hospital costs by 22.3%. Total burden to the UK health service exceeded £21 million each year. CONCLUSION: Postoperative morbidities are associated with a significant financial burden. Our findings could aid clinical teams and hospital providers to account for costs and contextualise quality improvement initiatives.
Assuntos
Procedimentos Cirúrgicos Cardíacos/economia , Custos Hospitalares/estatística & dados numéricos , Complicações Pós-Operatórias/economia , Adolescente , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Feminino , Cardiopatias Congênitas/economia , Cardiopatias Congênitas/cirurgia , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Análise de Regressão , Reino Unido/epidemiologiaRESUMO
Short-term survival after paediatric cardiac surgery has improved significantly over the past 20 years and increasing attention is being given to measuring and reducing incidence of morbidities following surgery. How to best use routinely collected data to share morbidity information constitutes a challenge for clinical teams interested in analysing their outcomes for quality improvement. We aimed to develop a tool facilitating this process in the context of monitoring morbidities following paediatric cardiac surgery, as part of a prospective multi-centre research study in the United Kingdom.We developed a prototype software tool to analyse and present data about morbidities associated with cardiac surgery in children. We used an iterative process, involving engagement with potential users, tool design and implementation, and feedback collection. Graphical data displays were based on the use of icons and graphs designed in collaboration with clinicians.Our tool enables automatic creation of graphical summaries, displayed as a Microsoft PowerPoint presentation, from a spreadsheet containing patient-level data about specified cardiac surgery morbidities. Data summaries include numbers/percentages of cases with morbidities reported, co-occurrences of different morbidities, and time series of each complication over a time window.Our work was characterised by a very high level of interaction with potential users of the tool, enabling us to promptly account for feedback and suggestions from clinicians and data managers. The United Kingdom centres involved in the project received the tool positively, and several expressed their interest in using it as part of their routine practice.
Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Indicadores de Qualidade em Assistência à Saúde/estatística & dados numéricos , Pré-Escolar , Comportamento Cooperativo , Humanos , Comunicação Interdisciplinar , Morbidade , Equipe de Assistência ao Paciente , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Design de Software , Análise de Sobrevida , Reino UnidoRESUMO
OBJECTIVES: Given the current excellent early mortality rates for paediatric cardiac surgery, stakeholders believe that this important safety outcome should be supplemented by a wider range of measures. Our objectives were to prospectively measure the incidence of morbidities following paediatric cardiac surgery and to evaluate their clinical and health-economic impact over 6 months. DESIGN: The design was a prospective, multicentre, multidisciplinary mixed methods study. SETTING: The setting was 5 of the 10 paediatric cardiac surgery centres in the UK with 21 months recruitment. PARTICIPANTS: Included were 3090 paediatric cardiac surgeries, of which 666 patients were recruited to an impact substudy. RESULTS: Families and clinicians prioritised:Acute neurological event, unplanned re-intervention, feeding problems, renal replacement therapy, major adverse events, extracorporeal life support, necrotising enterocolitis, postsurgical infection and prolonged pleural effusion or chylothorax.Among 3090 consecutive surgeries, there were 675 (21.8%) with at least one of these morbidities. Independent risk factors for morbidity included neonatal age, complex heart disease and prolonged cardiopulmonary bypass (p<0.001). Among patients with morbidity, 6-month survival was 88.2% (95% CI 85.4 to 90.6) compared with 99.3% (95% CI 98.9 to 99.6) with none of the morbidities (p<0.001). The impact substudy in 340 children with morbidity and 326 control children with no morbidity indicated that morbidity-related impairment in quality of life improved between 6 weeks and 6 months. When compared with children with no morbidities, those with morbidity experienced a median of 13 (95% CI 10.2 to 15.8, p<0.001) fewer days at home by 6 months, and an adjusted incremental cost of £21 292 (95% CI £17 694 to £32 423, p<0.001). CONCLUSIONS: Evaluation of postoperative morbidity is more complicated than measuring early mortality. However, tracking morbidity after paediatric cardiac surgery over 6 months offers stakeholders important data that are of value to parents and will be useful in driving future quality improvement.
Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Cardiopatias/cirurgia , Complicações Pós-Operatórias/epidemiologia , Adolescente , Fatores Etários , Procedimentos Cirúrgicos Cardíacos/mortalidade , Criança , Pré-Escolar , Feminino , Cardiopatias/diagnóstico , Cardiopatias/mortalidade , Humanos , Incidência , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Auditoria Médica , Multimorbidade , Complicações Pós-Operatórias/diagnóstico , Estudos Prospectivos , Indicadores de Qualidade em Assistência à Saúde , Retratamento , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Reino Unido/epidemiologiaRESUMO
OBJECTIVE: Given excellent 30-day survival for pediatric cardiac surgery, other outcome measures are important. We aimed to study important early postoperative morbidities selected by stakeholders following a rigorous and evidenced-based process, with a view to identifying potential risk factors. METHODS: The incidence of selected morbidities was prospectively measured for 3090 consecutive pediatric cardiac surgical admissions in 5 UK centers between October 2015 and June 2017. The relationship between the candidate risk factors and the incidence of morbidities was explored using multiple regressions. Patient survival, a secondary outcome, was checked at 6 months. RESULTS: A total of 675 (21.8%) procedure episodes led to at least 1 of the following: acute neurologic event, unplanned reoperation, feeding problems, renal replacement therapy, major adverse events, extracorporeal life support, necrotizing enterocolitis, surgical infection, or prolonged pleural effusion. The highest adjusted odds ratio of morbidity was in neonates compared with children, 5.26 (95% confidence interval, 3.90-7.06), and complex heart diseases (eg, hypoplastic left heart), 2.14 (95% confidence interval, 1.41-3.24) compared with low complexity (eg, atrial septal defect, P < .001 for all). Patients with any selected morbidity had a 6-month survival of 88.2% (95% confidence interval, 85.4-90.6) compared with 99.3% (95% confidence interval, 98.9-99.6) with no defined morbidity (P < .001). CONCLUSIONS: Evaluation of postoperative morbidity provides important information over and above 30-day survival and should become a focus for audit and quality improvement. Our results have been used to initiate UK-based audit for 5 of these 9 morbidities, co-develop software for local monitoring of these morbidities, and parent information about these morbidities.
Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Cardiopatias/cirurgia , Complicações Pós-Operatórias/epidemiologia , Adolescente , Fatores Etários , Procedimentos Cirúrgicos Cardíacos/mortalidade , Criança , Pré-Escolar , Feminino , Cardiopatias/diagnóstico , Cardiopatias/mortalidade , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Auditoria Médica , Multimorbidade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/terapia , Estudos Prospectivos , Indicadores de Qualidade em Assistência à Saúde , Retratamento , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Reino Unido/epidemiologiaRESUMO
BACKGROUND: Morbidity is defined as a state of being unhealthy or of experiencing an aspect of health that is "generally bad for you", and postoperative morbidity linked to paediatric cardiac surgery encompasses a range of conditions that may impact the patient and are potential targets for quality assurance. METHODS: As part of a wider study, a multi-disciplinary group of professionals aimed to define a list of morbidities linked to paediatric cardiac surgery that was prioritised by a panel reflecting the views of both professionals from a range of disciplines and settings as well as parents and patients. RESULTS: We present a set of definitions of morbidity for use in routine audit after paediatric cardiac surgery. These morbidities are ranked in priority order as acute neurological event, unplanned re-operation, feeding problems, the need for renal support, major adverse cardiac events or never events, extracorporeal life support, necrotising enterocolitis, surgical site of blood stream infection, and prolonged pleural effusion or chylothorax. It is recognised that more than one such morbidity may arise in the same patient and these are referred to as multiple morbidities, except in the case of extracorporeal life support, which is a stand-alone constellation of morbidity. CONCLUSIONS: It is feasible to define a range of paediatric cardiac surgical morbidities for use in routine audit that reflects the priorities of both professionals and parents. The impact of these morbidities on the patient and family will be explored prospectively as part of a wider ongoing, multi-centre study.
Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/mortalidade , Cardiopatias Congênitas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Criança , Consenso , Humanos , Morbidade , Pediatria , Garantia da Qualidade dos Cuidados de Saúde , Sociedades Médicas , Reino UnidoRESUMO
The detection of 6-acetylmorphine (6-AM) in urine by immunoassay methods is challenging due to its short half-life and its similarity in structure to many commonly abused opiates that are often present at very high concentrations in urine. Current 6-AM homogeneous enzyme immunoassays use lyophilized reagents because of the instability of 6-AM in water or lack of the required specificity due to high cross-reactivity with morphine. A new 6-AM rFab-based homogeneous enzyme immunoassay (HEIA) has been developed with highly improved specificity. Using a cutoff concentration of 10 ng/mL, morphine or morphine glucuronides did not produce a positive signal up to 300,000 or 1,000,000 ng/mL, respectively. Assay imprecision (n = 80) was less than 1.5% using four replicates per day for 20 days over the range 0-20 ng/mL. Cross-reactivity with structurally related or non-related compounds was assessed at concentrations up to 1,000,000 ng/mL. Interferences from endogenous compounds at ±25% cutoff were also performed at the concentrations ranging from 100,000 to 500,000 ng/mL. The effect of varied pH values on assay performance at ±25% cutoff was investigated; no false-positive or false-negative results were observed between pH 4 and -11. Based on the analysis of 149 authentic urine samples, the accuracy of the 6-AM HEIA compared with LC-MS-MS was 100%. These results demonstrated that rFab can be suitable for traditional HEIA with desired detection sensitivity and stability.
Assuntos
Técnicas Imunoenzimáticas , Fragmentos de Imunoglobulinas/química , Derivados da Morfina/urina , Analgésicos Opioides/urina , Cromatografia Líquida , Meia-Vida , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Morfina/urina , Sensibilidade e Especificidade , Manejo de Espécimes , Detecção do Abuso de Substâncias , Espectrometria de Massas em TandemRESUMO
Buprenorphine is now increasingly prescribed as an alternative to methadone for the treatment of heroin addiction. Because of its potency (dosage usages from 0.2 mg to 8 mg), the drug concentrations in body fluids are normally very low. Here, we report the first recombinant glucose-6-phosphate dehydrogenase (G6PDH)-based homogeneous immunoassay (EMIT-type assay) for free buprenorphine and free norbuprenorphine in urine. The antibody used in this assay cross-reacts nearly identically with buprenorphine and norbuprenorphine and, at the same time, has less than 1% cross-reactivity with a wide range of commonly prescribed opiates, particularly those structurally related compounds such as morphine, codeine, and dihydrocodeine. More importantly, this assay has a low detection limit of 1 ng/mL for buprenorphine or norbuprenorphine. Further evaluation of this technique using gas chromatography-mass spectrometry (GC-MS) of authentic urine samples demonstrated that the accuracy of the assay is greater than 95%. Because this assay is designed to measure the free drugs in urine, it resulted in simplification for GC-MS or liquid chromatography-MS confirmation methods that did not require urine hydrolysis before solid-phase or liquid-liquid extraction.