New telemetric system for daily pulmonary function surveillance of lung transplant recipients

Clinical Decision Support Systems Used in Transplantation: Are They Tools for Success or an Unnecessary Gadget? A Systematic Review

Although clinical decision support systems (CDSSs) have been used since the 1970s for a wide variety of clinical tasks including optimization of medication orders, improved documentation, and improved patient adherence, to date, no systematic reviews have been carried out to assess their utilization and efficacy in transplant medicine. The aim of this study is to systematically review studies that utilized a CDSS and assess impact on patient outcomes. A total of 48 articles were identified as meeting the author-derived inclusion criteria, including tools for posttransplant monitoring, pretransplant risk assessment, waiting list management, immunosuppressant management, and interpretation of histopathology. Studies included 15 984 transplant recipients. Tools aimed at helping with transplant patient immunosuppressant management were the most common (19 studies). Thirty-four studies (85%) found an overall clinical benefit following the implementation of a CDSS in clinical practice. Although there are limitations to the existing literature, current evidence suggests that implementing CDSS in transplant clinical settings may improve outcomes for patients. Limited evidence was found using more advanced technologies such as artificial intelligence in transplantation, and future studies should investigate the role of these emerging technologies.

Content, Mechanism, and Outcome of Effective Telehealth Solutions for Management of Chronic Obstructive Pulmonary Diseases: A Narrative Review

Telehealth (TH) solutions for Chronic Obstructive Pulmonary Disease (COPD) are promising behavioral therapeutic interventions and can help individuals living with COPD to improve their health status. The linking content, mechanism, and outcome of TH interventions reported in the literature related to COPD care are unknown. This paper aims to summarize the existing literature about structured TH solutions in COPD care. We conducted an electronic search of the literature related to TH solutions for COPD management up to October 2023. Thirty papers presented TH solutions as an innovative treatment to manage COPD. TH and digital health solutions are used interchangeably in the literature, but both have the potential to improve care, accessibility, and quality of life. To date, current TH solutions in COPD care have a variety of content, mechanisms, and outcomes. TH solutions can enhance education as well as provide remote monitoring. The content of TH solutions can be summarized as symptom management, prompt physical activity, and psychological support. The mechanism of TH solutions is manipulated by factors such as content, mode of delivery, strategy, and intensity. The most common outcome measures with TH solutions were adherence to treatment, health status, and quality of life. Implementing effective TH with a COPD care bundle must consider important determinants such as patient's needs, familiarity with the technology, healthcare professional support, and data privacy. The development of effective TH solutions for COPD management also must consider patient engagement as a positive approach to optimizing implementation and effectiveness.

A comparison of clinic and home spirometry as longtudinal outcomes in cystic fibrosis

Background

The COVID-19 pandemic has accelerated the transition to telehealth, including the use of home spirometry in cystic fibrosis. Evaluating the accuracy and precision of longitudinal home spirometry is a requisite for telehealth-based research. This secondary analysis of a CF study (eICE) evaluates whether there are cross-sectional or longitudinal differences between home and clinic spirometry.

Methods

Participants age ≥14 years with ppFEV₁>25 were recruited from 2011-2015, issued a home spirometer, and asked to complete spirometry efforts twice per week for one year. Clinic spirometry was collected at baseline and every three months. Cross-sectional differences between clinic spirometry and the closest home spirometry measurement were analyzed. Longitudinally, we apply 5 methods to analyze the precision of home spirometry, and differences between clinic vs. home data.

Results

Home spirometry is estimated to be 2.0 (95% CI: 0.3, 3.5) percentage points lower than clinic spirometry cross-sectionally. Longitudinally, the estimates of 12-month change in home spirometry varied by analysis method from -2.6 to -1.0 ppFEV₁/ year, with precision markedly different. However, home spirometry change estimates were qualitatively similar to the clinic results: -3.0 ppFEV₁/year (95% CI: -4.1, -1.9).

Conclusions

To leverage the potential cost, feasibility and convenience of home spirometry, the differences with clinic spirometry must be acknowledged. Significantly lower ppFEV₁ in home devices shows that direct comparison to clinic spirometers may induce a spurious change from baseline, and additional variability in home devices impacts statistical power. The effect of coaching, setting, and equipment must be understood to use and improve home spirometry in CF.

Extracorporeal photopheresis to attenuate decline in lung function due to refractory obstructive allograft dysfunction

BACKGROUND

This study was designed to prospectively evaluate the efficacy of extracorporeal photopheresis (ECP) to attenuate the rate of decline of FEV₁ in lung transplant recipients with refractory bronchiolitis obliterans. Due to an observed higher than expected early mortality, a preliminary analysis was performed.

STUDY DESIGN AND METHODS

Subjects from 10 lung transplant centres were assigned to ECP treatment or to observation based on spirometric criteria, with potential crossover for those under observation. The primary endpoint of this study was to assess response to ECP (i.e., greater than a 50% decrease in the rate of FEV₁ decline) before and 6 months after initiation of ECP. Mortality was also evaluated 6 and 12 months after enrolment as a secondary endpoint.

RESULTS

Of 44 enrolled subjects, 31 were assigned to ECP treatment while 13 were initially assigned to observation on a non-random basis using specific spirometric inclusion criteria (seven of the observation patients subsequently crossed over to receive ECP). Of evaluable patients, 95% of patients initially assigned to treatment responded to ECP with rates of FEV₁ decline that were reduced by 93% in evaluable ECP-treated patients. Mortality rates (percentages) at 6 and 12 months after enrolment was 32% and 41%, respectively. The most common (92%) primary cause of death was respiratory or graft failure. Significantly (p = 0.002) higher rates of FEV₁ decline were observed in the non-survivors (-212 ± 177 ml/month) when compared to the survivors (-95 ± 117 ml/month) 12 months after enrolment. In addition, 18 patients with bronchiolitis obliterans syndrome (BOS) diagnosis within 6 months of enrolment had lost 38% of their baseline lung function at BOS diagnosis and 50% of their lung function at enrolment.

CONCLUSIONS

These analyses suggest that earlier detection and treatment of BOS should be considered to appreciate improved outcomes with ECP.

Home Monitoring for Lung Transplant Candidates

Home monitoring by lung transplant recipients has been effective for early detection of clinical problems. This study used an electronic diary for home monitoring by lung transplant candidates to improve communication between candidates and the transplant team. Candidates were randomized into control (52 subjects following standard telephone reporting procedures) and intervention (67 subjects using an electronic diary to record and transmit a range of health-related measures) groups. Outcome measures were monitoring adherence and level of communication (for monitor acceptability and utilization), hospital length of stay after transplantation and survival at 4 months (for clinical effectiveness). Subjects used the diary without difficulty and with good adherence. Subjects and coordinator contacts were similar between groups; intervention group subjects were positive regarding contact based on diary use. There were no significant differences in clinical outcomes between groups. Changing diary questions might improve the effectiveness of electronic monitoring for lung transplant candidates.

Using mobile health technology to deliver decision support for self-monitoring after lung transplantation

BACKGROUND

Lung transplant recipients (LTR) experience problems recognizing and reporting critical condition changes during their daily health self-monitoring. Pocket PATH(®), a mobile health application, was designed to provide automatic feedback messages to LTR to guide decisions for detecting and reporting critical values of health indicators.

OBJECTIVES

To examine the degree to which LTR followed decision support messages to report recorded critical values, and to explore predictors of appropriately following technology decision support by reporting critical values during the first year after transplantation.

METHODS

A cross-sectional correlational study was conducted to analyze existing data from 96 LTR who used the Pocket PATH for daily health self-monitoring. When a critical value is entered, the device automatically generated a feedback message to guide LTR about when and what to report to their transplant coordinators. Their socio-demographics and clinical characteristics were obtained before discharge. Their use of Pocket PATH for health self-monitoring during 12 months was categorized as low (≤25% of days), moderate (>25% to ≤75% of days), and high (>75% of days) use. Following technology decision support was defined by the total number of critical feedback messages appropriately handled divided by the total number of critical feedback messages generated. This variable was dichotomized by whether or not all (100%) feedback messages were appropriately followed. Binary logistic regression was used to explore predictors of appropriately following decision support.

RESULTS

Of the 96 participants, 53 had at least 1 critical feedback message generated during 12 months. Of these 53 participants, the average message response rate was 90% and 33 (62%) followed 100% decision support. LTR who moderately used Pocket PATH (n=23) were less likely to follow technology decision support than the high (odds ratio [OR]=0.11, p=0.02) and low (OR=0.04, p=0.02) use groups. The odds of following decision support were reduced in LTR whose income met basic needs (OR=0.01, p=0.01) or who had longer hospital stays (OR=0.94, p=0.004). A significant interaction was found between gender and past technology experience (OR=0.21, p=0.03), suggesting that with increased past technology experience, the odds of following decision support to report all critical values decreased in men but increased in women.

CONCLUSIONS

The majority of LTR responded appropriately to mobile technology-based decision support for reporting recorded critical values. Appropriately following technology decision support was associated with gender, income, experience with technology, length of hospital stay, and frequency of use of technology for self-monitoring. Clinicians should monitor LTR, who are at risk for poor reporting of recorded critical values, more vigilantly even when LTR are provided with mobile technology decision support.

A randomized controlled trial comparing health and quality of life of lung transplant recipients following nurse and computer-based triage utilizing home spirometry monitoring

BACKGROUND

Lung transplantation is now a standard intervention for patients with advanced lung disease. Home monitoring of pulmonary function and symptoms has been used to follow the progress of lung transplant recipients in an effort to improve care and clinical status. The study objective was to determine the relative performance of a computer-based Bayesian algorithm compared with a manual nurse decision process for triaging clinical intervention in lung transplant recipients participating in a home monitoring program.

MATERIALS AND METHODS

This randomized controlled trial had 65 lung transplant recipients assigned to either the Bayesian or nurse triage study arm. Subjects monitored and transmitted spirometry and respiratory symptoms daily to the data center using an electronic spirometer/diary device. Subjects completed the Short Form-36 (SF-36) survey at baseline and after 1 year. End points were change from baseline after 1 year in forced expiratory volume at 1 s (FEV1) and quality of life (SF-36 scales) within and between each study arm.

RESULTS

There were no statistically significant differences between groups in FEV1 or SF-36 scales at baseline or after 1 year.: Results were comparable between nurse and Bayesian system for detecting changes in spirometry and symptoms, providing support for using computer-based triage support systems as remote monitoring triage programs become more widely available.

CONCLUSIONS

The feasibility of monitoring critical patient data with a computer-based decision system is especially important given the likely economic constraints on the growth in the nurse workforce capable of providing these early detection triage services.

Rationale and design of a randomized trial of home electronic symptom and lung function monitoring to detect cystic fibrosis pulmonary exacerbations: the early intervention in cystic fibrosis exacerbation (eICE) trial

BACKGROUND

Acute pulmonary exacerbations are central events in the lives of individuals with cystic fibrosis (CF). Pulmonary exacerbations lead to impaired lung function, worse quality of life, and shorter survival. We hypothesized that aggressive early treatment of acute pulmonary exacerbation may improve clinical outcomes.

PURPOSE

Describe the rationale of an ongoing trial designed to determine the efficacy of home monitoring of both lung function measurements and symptoms for early detection and subsequent early treatment of acute CF pulmonary exacerbations.

STUDY DESIGN

A randomized, non-blinded, multi-center trial in 320 individuals with CF aged 14 years and older. The study compares usual care to a twice a week assessment of home spirometry and CF respiratory symptoms using an electronic device with data transmission to the research personnel to identify and trigger early treatment of CF pulmonary exacerbation. Participants will be enrolled in the study for 12 months. The primary endpoint is change in FEV1 (L) from baseline to 12 months determined by a linear mixed effects model incorporating all quarterly FEV1 measurements. Secondary endpoints include time to first acute protocol-defined pulmonary exacerbation, number of acute pulmonary exacerbations, number of hospitalization days for acute pulmonary exacerbation, time from the end of acute pulmonary exacerbation to onset of subsequent pulmonary exacerbation, change in health related quality of life, change in treatment burden, change in CF respiratory symptoms, and adherence to the study protocol.

CONCLUSIONS

This study is a first step in establishing alternative approaches to the care of CF pulmonary exacerbations. We hypothesize that early treatment of pulmonary exacerbations has the potential to slow lung function decline, reduce respiratory symptoms and improve the quality of life for individuals with CF.

Automatic event detection in lung transplant recipients based on home monitoring of spirometry and symptoms

OBJECTIVE

The goal of this study was to develop, implement, and test an automated decision system to provide early detection of clinically important bronchopulmonary events in a population of lung transplant recipients following a home monitoring protocol.

SUBJECTS AND METHODS

Spirometry and other clinical data were collected daily at home by lung transplant recipients and transmitted weekly to the study data center. Decision rules were developed using wavelet analysis of declines in spirometry and increases in respiratory symptoms from a learning set of patient home data and validated with an independent patient set.

RESULTS

Using forced expiratory volume in 1 s or symptoms, the detection captured the majority of events (sensitivity, 80-90%) at an acceptable level of false alarms. On average, detections occurred 6.6-10.8 days earlier than the known event records.

CONCLUSIONS

This approach is useful for early discovery of pulmonary events and has the potential to decrease the time required for humans to review large amount of home monitoring data to discover relatively infrequent but clinically important events.

Telehealth Interventions for Management of Chronic Obstructive Lung Disease (COPD) and Asthma

The authors systematically collated, classified, and evaluated the evidence of intervention studies from recent systematic reviews about the effects of telehealth interventions on COPD and asthma care. Eight electronic databases were searched. Eligible articles were those published between 2001 and 2011 in English. Eleven review articles are included. Asthma and COPD are better controlled when patients use interactive technological tools to monitor their chronic disease. The effects of telehealth interventions on emergency department attendance, specific quality of life, and mortality remained less certain. Only some reviews mentioned if the cost-effectiveness was systematically analyzed. Telehealth promises to be a highly effective intervention in managing chronic lung diseases while also potentially reducing some of the economic burdens of asthma and COPD. New directions in telehealth developments, implementations, and evaluations should be made, in which the exchange of health information should not be over simplified, but rather reflect the different socio-cultural practices of population groups and individuals.

Significance of patient self-monitoring for long-term outcomes after lung transplantation

BACKGROUND

Lung transplant (LTx) recipients' adherence to regular self-monitoring of lung function (SMLF) is important in maintaining health. This study investigated patients' behavior based on electronic monitoring (EM) and compared these findings with self-reported data.

METHODS

This single-center study included 269 patients following LTx. Patients reported on adherence regarding SMLF, and data were compared to electronically stored measurements for the last three months prior to self-reporting.

RESULTS

Non-adherence was 59.4% based on EM for a total of 22,052 measurements performed. Main reported reasons for non-adherence were forgetfulness (22%), lack of time (19%), and good self-perception of health status (19%). Determinants for non-adherence were patients constraining beliefs (p ≤ 0.0001), low perceived support from the transplant center (p ≤ 0.008), a history of infections (p ≤ 0.014) and rejections (p ≤ 0.043), and bronchiolitis obliterans (p ≤ 0.006). Multiple logistic regression revealed low-perceived support from the transplant center (OR 3.22; 95% CI 1.32-7.83; p < 0.01), and lack of support from patient organizations (OR 2.19; 95% CI 1.02-4.72; p < 0.04) as independent predictors for non-adherence.

CONCLUSIONS

LTx recipients had some difficulties maintaining SMLF on a daily basis. Non-adherence regarding lung function monitoring may provide a clinically relevant estimate of suspect cases for critical events impacting outcomes after LTx.

Cost analysis of home monitoring in lung transplant recipients

OBJECTIVES

The University of Minnesota has maintained a home monitoring program for over 10 years for lung and heart-lung transplant patients. A cost analysis was completed to assess the impact of home monitoring on the cost of post-transplant medical care.

METHODS

Clinical information gathered with the monitoring system includes spirometry, vital signs, and symptom data. To estimate the impact of this system on medical costs, we completed a retrospective analysis of the effects of home monitoring on the cost of post-lung transplant medical care. The cost analysis used multivariate linear regression with inpatient, outpatient, and total medical care costs as the dependent variables. The independent variables for the regression include home monitoring adherence, underlying disease, ambulatory diagnostic group mapping variables, transplant type, and patient demographics.

RESULTS

The multivariate regression of the overall cost results predicts a 52.4 percent reduction in total costs with 100 percent patient adherence; this rate includes a 72.24 percent reduction in inpatient costs and a 46.6 percent increase in outpatient costs. The actual first year average patient adherence was 74 percent.

CONCLUSIONS

Adherence to home monitoring increases outpatient costs and reduces inpatient costs and provides an overall cost savings. The break-even point for patient adherence was 25.28 percent, where the net savings covered the cost of home monitoring. This is well within the actual first year adherence rates (74 percent) for subjects in the lung transplant home monitoring program, providing a net savings with adherence to home monitoring.

Systematic review of home telemonitoring for chronic diseases: the evidence base

OBJECTIVE

Home telemonitoring represents a patient management approach combining various information technologies for monitoring patients at distance. This study presents a systematic review of the nature and magnitude of outcomes associated with telemonitoring of four types of chronic illnesses: pulmonary conditions, diabetes, hypertension, and cardiovascular diseases.

METHODS

A comprehensive literature search was conducted on Medline and the Cochrane Library to identify relevant articles published between 1990 and 2006. A total of 65 empirical studies were obtained (18 pulmonary conditions, 17 diabetes, 16 cardiac diseases, 14 hypertension) mostly conducted in the United States and Europe.

RESULTS

The magnitude and significance of the telemonitoring effects on patients' conditions (e.g., early detection of symptoms, decrease in blood pressure, adequate medication, reduced mortality) still remain inconclusive for all four chronic illnesses. However, the results of this study suggest that regardless of their nationality, socioeconomic status, or age, patients comply with telemonitoring programs and the use of technologies. Importantly, the telemonitoring effects on clinical effectiveness outcomes (e.g., decrease in the emergency visits, hospital admissions, average hospital length of stay) are more consistent in pulmonary and cardiac studies than diabetes and hypertension. Lastly, economic viability of telemonitoring was observed in very few studies and, in most cases, no in-depth cost-minimization analyses were performed.

CONCLUSION

Home telemonitoring of chronic diseases seems to be a promising patient management approach that produces accurate and reliable data, empowers patients, influences their attitudes and behaviors, and potentially improves their medical conditions. Future studies need to build evidence related to its clinical effects, cost effectiveness, impacts on services utilization, and acceptance by health care providers.

Telemetric Monitoring of Pulmonary Function After Allogeneic Hematopoietic Stem Cell Transplantation

BACKGROUND

Late-onset noninfectious pulmonary complications (LONIPC) are both frequent and severe after allogeneic hematopoietic stem cell transplantation (HSCT). The high mortality rate (40-80%) may be related to delayed diagnosis. We assessed the use of telemetric home surveillance of pulmonary function for early diagnosis of LONIPC in transplant recipients.

METHODS

This prospective study monitored pulmonary function in 37 allogeneic HSCT recipients. About 3 months after HSCT, they received a portable spirometer that measured forced vital capacity, forced expiratory volume per second, and midexpiratory flow 25-75 (MEF25-75). Data were transmitted twice weekly by telephone. Conventional plethysmography confirmed any significant deterioration (>20%).

RESULTS

Thirteen episodes of spirometric deterioration were detected by telemetry in 11 patients during a median 17-month (4-41) follow-up period after transplantation. In these cases, examinations including spirometry, high-resolution thoracic computed tomography and bronchoalveolar lavage diagnosed LONIPC in eight episodes in seven patients (cumulative incidence 23.4%, SE 0.08, at month 24 after transplant): bronchiolitis obliterans (BO, n=3), interstitial pneumonia (IP, n=4), or both BO and IP (n=1). Five episodes improved and three were stabilized with increased immunosuppressive therapy. At the last follow-up, of the seven patients with LONIPC, one successfully stopped immunosuppressive therapy, two were receiving low-dose mycophenolate mofetil, and four were receiving low-dose corticosteroid therapy. There were no cases of respiratory failure and no patient died from LONIPC.

CONCLUSION

Telemetric home monitoring of pulmonary function is a useful procedure for early diagnosis of LONIPC before clinical pulmonary symptoms and may improve outcome after allogeneic HSCT.

The design of an Internet-based system to maintain home monitoring adherence by lung transplant recipients

Regimen adherence is a key factor in the success of home monitoring of lung transplant recipients. Patients generally adhere satisfactorily with home spirometry in the short-term, but adherence tends to decline over time. Telehealth and Internet technology provide new methods to address this issue. The unique contribution of the Adherence Enhancement Internet Program (AEIP) is the integration of multiple adherence enhancement strategies operating in a unified approach to the adherence problem, while meshing all user groups to facilitate interactions. This Internet-based program focused on promoting subject specific strategies was developed to maintain the initial high levels of adherence beyond the first year post transplant. The program provides more immediate subject feedback related to home monitoring data, reminders from the patient's health care providers, educational material, and guidance in dealing with subject specific barriers to maintaining adherence. It also simplifies communication between patients and health care providers, and supports providers in certain patient care tasks. A feasibility trial involving 12 lung transplant recipients demonstrated that subjects were able to use the AEIP with little training, found it acceptable, and were generally enthusiastic regarding it as a tool to maintain or enhance adherence.

Adherence to the Therapeutic Regimen in Heart, Lung, and Heart-Lung Transplant Recipients

Optimal outcome after heart, lung, and heart-lung transplantation can only be obtained if patients are supported in adhering to a lifelong therapeutic regimen. The transplant patient's therapeutic regimen consists of a lifelong medication regimen, including immunosuppressive drugs; monitoring for signs and symptoms related to complications; avoidance of risk factors for cardiovascular disease and cancer (ie, diet and exercise prescriptions, nonsmoking); avoidance of abuse/dependence of alcohol or illegal drugs, as well as attending regular clinical checkups. Nonadherence to all aspects of this regimen is substantial. Nonadherence has been related to negative clinical outcome in view of acute rejections, graft vasculopathy, higher costs, and mortality. This review focuses on the prevalence, correlates, and consequences of nonadherence to the therapeutic regimen in heart, lung, and heart-lung transplantation. The current state of the-art on adherence-enhancing interventions is reported. Priorities for future research are outlined.

Incomplete Event Documentation in Medical Records of Lung Transplant Recipients

Context

The medical record is frequently used in clinical studies as a source of information on illness events experienced by patients; however, it may be incomplete.

Objective

To estimate the extent of incompletely documented acute bronchopulmonary events in a transplant clinic medical record at a single university medical center, using home monitoring data.

Design, Setting, and Subjects

Trends in daily home monitoring data were compared to contemporaneous medical record documentation at 150 different times in 30 lung transplant recipients over 45 subject-years.

Outcome Measure

Proportion of acute bronchopulmonary illness events documented in clinic medical record.

Results

By using home monitoring data in a new way, we found that 40% of events actually suffered by lung recipients could not be ascertained to have occurred from the clinic medical record alone. All missed encounters occurred away from the transplant clinic, and involved hospitalizations and telephone prescriptions.

Conclusions

Using the clinic medical record alone to identify acute bronchopulmonary events in lung transplant recipients may result in missing 40% of events. This has important ramifications for studies relying on the medical record for acute event ascertainment in lung transplantation and possibly other chronic diseases.

Decision support for the triage of lung transplant recipients on the basis of home-monitoring spirometry and symptom reporting

Purpose The objective of this study was to develop and evaluate a computerized rule-based decision support algorithm for nursing triage of potential acute bronchopulmonary events in lung transplant recipients on the basis of home monitoring of spirometry and symptoms. Methods The algorithm automatically separates recipients into 2 groups: those who are stable or improving and those who should be "watched" further because of their potential for developing bronchopulmonary events according to their weekly home-monitoring measurements. A total of 155 recipients (82 females and 73 males) contributed 1944 weekly records for the training (420), testing (786), and prospective evaluation (738) data sets. Weekly records contained daily values of forced expiratory volume at 1 second and respiratory symptoms, which were the inputs for the triage rules. Results Sensitivity and specificity were greater than 90% for the prospective evaluation comparing the computer decision support system with the manual nurse review of the same home-monitoring reports. Conclusions Algorithm performance in identifying lung recipients who should be placed on a "watch" list for the potential to develop acute bronchopulmonary events is comparable to the standard human clinical review of the same weekly home-monitoring data.

Relevance of a portable spirometer for detection of small airways obstruction

While portable spirometers are increasingly used, little attention has been paid to test their validity for measurement of flows in small airways. The aim of this study was to compare the Spirotel portable spirometer to a laboratory spirometer (Jeager PFT), with regard to accuracy in measuring forced expiratory flows, and more specifically those influenced by small airways (FEF(25-75)). Fifty-nine children (mean age, 12 years; range, 7-17), were studied at baseline and after a bronchodilator inhalation. Spirometers were tested separately in a randomly designed order. A total of 117 sessions of flow-volume curves was performed with each spirometer. We obtained at least two acceptable and reproducible curves in 88% and 76% of the sessions, with the laboratory and the portable spirometers, respectively. Unacceptable curves were easily detected by visual inspection of flow-time and flow-volume waveforms. Agreement was excellent between spirometers for the measurement of all expiratory flows, both at baseline and postbronchodilator. More specifically, agreement between spirometers was as high for measurements of FEF(25-75) (intraclass correlation coefficients 0.97) as for proximal flows. High correlations were found between baseline expiratory flows measured by each spirometer (and expressed as percent of predicted values), both in large and small airways (P < 0.001). The portable spirometer was highly sensitive for detecting small airways obstruction, as compared to the laboratory spirometer. Finally, the magnitudes of bronchodilator-related flow changes were also highly correlated, both in large and small airways (P < 0.001 and P = 0.004, respectively). We conclude that the Spirotel portable spirometer is reliable for measurement of forced expiratory flows, in large and small airways, provided that all curve waveforms can be stored and available for visual inspection.

Comparison of Bayesian, classical, and heuristic approaches in identifying acute disease events in lung transplant recipients

This study compares a typical heuristic algorithm with classical and Bayesian regression models in ascertaining the presence of acute bronchopulmonary disease events in lung transplant recipients. These models attempt to predict whether an epoch will end in an event, based on the preceding two weeks of data. The data consist of 150 two-week epochs of daily to biweekly spirometry and symptom covariates for 30 subjects over 60 subject-years. Seventy-five 'event' epochs end on a day when an acute bronchopulmonary disease event is documented in the medical record; 75 randomly selected 'non-event' epochs end on a day when no event is documented. The data are partitioned by randomly assigning 15 subjects for training and the remaining 15 subjects for testing. For cross-validation, a second random partition is generated from the same data set. The statistical models are trained and tested on both partitions. For the heuristic algorithm, its historical event classifications on the same test cases are used. Classification performance on both partitions of all models is compared using receiver operating characteristic curves, sensitivity and specificity, and a Shannon information score. Data partition did not appreciably affect statistical model performance. All statistical models, unlike the heuristic algorithm, performed significantly different than chance (family significance < 0.05, Pearson independence chi-square, Bonferroni multiple correction), and better than the heuristic algorithm. The best models were Bayesian changepoint models. Through a clinically oriented discussion, a case classified by all of these algorithms is presented, suggesting the clinical usefulness of the Bayesian approach compared with the classical and heuristic approaches.

Home monitoring for lung transplant candidates

Home monitoring by lung transplant recipients has been effective for early detection of clinical problems. This study used an electronic diary for home monitoring by lung transplant candidates to improve communication between candidates and the transplant team. Candidates were randomized into control (52 subjects following standard telephone reporting procedures) and intervention (67 subjects using an electronic diary to record and transmit a range of health-related measures) groups. Outcome measures were monitoring adherence and level of communication (for monitor acceptability and utilization), hospital length of stay after transplantation and survival at 4 months (for clinical effectiveness). Subjects used the diary without difficulty and with good adherence. Subjects and coordinator contacts were similar between groups; intervention group subjects were positive regarding contact based on diary use. There were no significant differences in clinical outcomes between groups. Changing diary questions might improve the effectiveness of electronic monitoring for lung transplant candidates.

Bronchiolitis obliterans syndrome

BOS remains a difficult problem to control following lung transplantation, largely because of uncertainties regarding the underlying mechanisms that are responsible for it. Continued work on the pathogenesis of BOS is essential. The progressive nature and poor outlook when BOS stage 3 is reached indicates that current strategies should be focused on prevention and early intervention. There is a great need for randomized, controlled trials on intervention if the international transplant community is to make progress in this area.

Internet-based home monitoring of pulmonary function after lung transplantation

Home monitoring of spirometry has been advocated in lung transplant recipients for the early detection of acute infection and rejection of the allograft. We have developed a user-friendly, Internet-based telemonitoring system providing direct transmission of home spirometry to the hospital. In this prospective study, we assessed patient adherence with the monitoring, agreement between home and hospital spirometry, intrasubject coefficient of variation (CV) for FEV(1) and FEF(25-75), and sensitivity of these variables for the detection of acute complications. Twenty-two bilateral-lung and heart-lung transplant recipients were followed for a median of 473 d (range, 60-822), during which 13,833 measurements were obtained. Patient compliance was 55% for two measurements a day and 84% for one measurement a day. Agreement between home and hospital spirometry was within 4% for FEV(1) and 6% for FEF(25-75). Mean CV was 3.2% for FEV(1) and 7.5% for FEF(25-75). Using transbronchial lung biopsy and/or bronchoalveolar lavage as gold standards, the sensitivity of home spirometry was 63%, and 23% of true positives were detected by changes in FEF(25-75) alone. We conclude that home monitoring of pulmonary function in lung transplant recipients via the Internet is feasible and provides very reproducible data; yet it has only a mild sensitivity for the detection of acute allograft dysfunction.