Lung transplantation for cystic fibrosis: a single center experience of 100 consecutive cases

Telemonitoring: An opportunity in cystic fibrosis lung transplant recipients

Introduction

Telemedicine has been successfully employed in a wide range of conditions, such as such as chronic lung disease and COVID-19. This study evaluate the role of telemonitoring for the early diagnosis of acute lung allograft dysfunction in cystic fibrosis adults who underwent lung transplant (LuTx). Quality of life and functional level achieved during a 12 months follow up were assessed.

Methods

Patients were randomized into two groups; control group received traditional hospital-based follow-up, whereas patients in the intervention group received, on top of standard care, a telemonitoring device, with a pulse oximeter and a spirometer integrated. Telemonitoring data were digitally transmitted to our centre.

Results

Sixteen patients were enrolled in each group. No statistically significant difference was found between the two groups in terms of incidence of allograft dysfunction, time from onset of symptoms to diagnosis and time of occurrence from LuTx. Moreover, both groups achieved similar quality of life and functional level. With reference to the telemonitoring group: 1) hospital reported data were consistent with those being remotely registered; 2) adherence to telemonitoring decreased during the follow up; 3) the majority of patients reported a high degree of satisfaction.

Conclusion

The COVID19 pandemic highlighted the necessity to investigate alternative practices to treat chronically ill individuals. Telemonitoring is a valuable tool to improve quality care to LuTx recipients.

Predictors of long intensive care need after lung transplantation

BACKGROUND

While expected need for intensive care after lung transplantation (LTx) does not normally affect organ allocation, it would be useful to estimate whether intensive care capacity is limited. The aim of this study was to assess factors available before LTx to identify predictors of prolonged intensive care unit (ICU) length of stay (LOS) after LTx.

METHODS

All bilateral LTx recipients excluding re-transplantation and multi-organ transplantation at Oslo University Hospital from 2000 to 2013 were included (n = 277). Predictive factors for ICU LOS were identified using pre- and perioperative variables.

RESULTS

Univariate analyses showed that recipients with pulmonary arterial hypertension, young age, female gender, low body height, low pretransplant actual total lung capacity (aTLC), and recipients who received an oversized donor lung were at risk for long ICU LOS. Patients with emphysema had lower risk of long ICU LOS. In multivariate analyses, a lower aTLC (p < .001) and a higher mean pulmonary artery pressure (mPAP) (p = .004) predicted prolonged ICU LOS.

CONCLUSIONS

We found that small recipient lung volume and high mPAP were predictors for prolonged ICU LOS. Our observations may be useful in planning use of resources in LTx, particularly in times of limited intensive care resources.

A pragmatic behavior-based habit index for adherence to nebulized treatments among adults with cystic fibrosis

BACKGROUND

Habit, a psychological process that automatically generates urges to perform a behavior in associated settings, is potentially an important determinant of medication adherence. Habit is challenging to measure because, as a psychological construct, it cannot be directly observed. We describe a method of using routinely available objective adherence data from electronic data capture (EDC) to generate a behavior-based index of adherence habit and demonstrate how this index can be applied.

METHODS TO GENERATE THE HABIT INDEX

Our proposed habit index is a "frequency in context" measure. It estimates habit as a multiplicative product of behavior frequency (generated from weekly percentage adherence) and context stability (inferred from time of nebulizer use). Although different timescales can be used, we chose to generate weekly habit scores since we believe that this is the most granular level at which context stability can be reasonably calculated.

AN APPLICATION OF THE HABIT INDEX

A hallmark of habit is to predict future behavior, hence we used time series method to cross-correlate the habit index with nebulizer adherence in the subsequent week among 123 adults with cystic fibrosis (52, 42.3% female; median age 25 years) over a median duration of 153 weeks (IQR 74-198 weeks). The mean cross-correlation coefficient (R) between the habit index and subsequent adherence was 0.40 (95% CI 0.36-0.44). Adjusting for current adherence, the unstandardized regression coefficient (B) for the habit index was 0.30 (95% CI -1.04 to 1.65).

CONCLUSION

We have described a pragmatic method to infer "habit" from adherence data routinely captured with EDC and provided proof-of-principle evidence regarding the feasibility of this concept. The continuous stream of data from EDC allows the habit index to unobtrusively assess "habit" at various time points over prolonged periods, and hence the habit index may be applicable in habit formation studies.

Survival After Lung Transplant for Cystic Fibrosis in Italy: A Single Center Experience With 20 Years of Follow-up

OBJECTIVES

Lung transplantation is currently the only treatment for end-stage respiratory failure in patients with cystic fibrosis (CF). In this study we retrospectively analyzed our experience since the start of the transplantation program in 1996 with focus on survival analysis.

METHODS

All patients with CF who underwent lung transplant at our center were included (1996-2016). Survival analysis after lung transplant was performed using the Kaplan-Meier estimate, comparing by sex and by 4 eras (1996-2000, 2001-2005, 2006-2010, and 2011-2016).

RESULTS

In a 20-year period, 243 patients with CF were listed for lung transplant; 123 patients (61 male, 62 female) underwent transplant, and 85 died while waiting for donor organs. The mean (SD) and median age at transplant was 27.7 (8.7) years and 26.9 years (range, 9.1 - 52.1 years), respectively. Mean (SD) forced expiratory volume in the first second was 27.6 (9.7)% predicted; 115 patients (92.0%) were pancreatic insufficient, and 43 patients (34.0%) had CF-related diabetes. Removing patients with CF who died within the first 3 postoperative months, the mean (SD) and median survival after transplant were 8.2 (5.7) years and 7.5 years (range, 3 months-20 years), respectively. Overall post-lung transplant 1-year survival was 93.6%, 5-year survival was 71.4%, 10-year survival was 53.6%, 15-year survival was 36.7%, and 20-year survival was 31.6%. We found no difference in survival between sex (P = .22) and among the 4 eras (P = .56).

CONCLUSIONS

Survival after lung transplant in our single center is similar to international data.

Using different methods to process forced expiratory volume in one second (FEV 1) data can impact on the interpretation of FEV 1 as an outcome measure to understand the performance of an adult cystic fibrosis centre: A retrospective chart review

Background: Forced expiratory volume in one second (FEV 1) is an important cystic fibrosis (CF) prognostic marker and an established endpoint for CF clinical trials. FEV 1 is also used in observation studies, e.g. to compare different centre's outcomes. We wished to evaluate whether different methods of processing FEV 1 data can impact on a centre's outcome. Methods: This is a single-centre retrospective analysis of routinely collected data from 2013-2016 which included 208 adults with CF. Year-to-year %FEV 1 change was calculated by subtracting best %FEV 1 at Year 1 from Year 2 (i.e. negative values indicate %FEV 1 decline), and compared using Friedman test. Three methods were used to process %FEV 1 data. First, %FEV 1 calculated with Knudson equation was extracted directly from spirometer machines. Second, FEV 1 volume were extracted then converted to %FEV 1 using clean height data and Knudson equation. Third, FEV 1 volume were extracted then converted to %FEV 1 using clean height data and GLI equation. In addition, %FEV 1 decline calculated using GLI equation was adjusted for baseline %FEV 1 to understand the impact of case-mix adjustment. Results: There was a trend of reduction in %FEV 1 decline with all three data processing methods but the magnitude of %FEV 1 decline differed. Median change in %FEV 1 for 2013-2014, 2014-2015 and 2015-2016 was -2.0, -1.0 and 0.0 respectively using %FEV 1 in Knudson equation whereas the median change was -1.1, -0.9 and -0.3 respectively using %FEV 1 in the GLI equation. A statistically significant p-value (0.016) was only obtained when using %FEV 1 in Knudson equation extracted directly from spirometer machines. Conclusions: Although the trend of reduction in %FEV 1 decline was robust, different data processing methods yielded varying results when %FEV 1 decline was compared using a standard related group non-parametric statistical test. Observational studies with %FEV 1 decline as an outcome measure should carefully consider and clearly specify the data processing methods used.

Using different methods to process forced expiratory volume in one second (FEV 1) data can impact on the interpretation of FEV 1 as an outcome measure to understand the performance of an adult cystic fibrosis centre: A retrospective chart review

Background: Forced expiratory volume in one second (FEV 1) is an important cystic fibrosis (CF) prognostic marker and an established endpoint for CF clinical trials. FEV 1 is also used in observation studies, e.g. to compare different centre's outcomes. We wished to evaluate whether different methods of processing FEV 1 data can impact on centre outcome. Methods: This is a single-centre retrospective analysis of routinely collected data from 2013-2016 among 208 adults. Year-to-year %FEV 1 change was calculated by subtracting best %FEV 1 at Year 1 from Year 2 (i.e. negative values indicate fall in %FEV 1), and compared using Friedman test. Three methods were used to process %FEV 1 data. First, %FEV 1 calculated with Knudson equation was extracted directly from spirometer machines. Second, FEV 1 volume were extracted then converted to %FEV 1 using clean height data and Knudson equation. Third, FEV 1 volume were extracted then converted to %FEV 1 using clean height data and GLI equation. In addition, year-to-year variation in %FEV 1 calculated using GLI equation was adjusted for baseline %FEV 1 to understand the impact of case-mix adjustment. Results: Year-to-year fall in %FEV 1 reduced with all three data processing methods but the magnitude of this change differed. Median change in %FEV 1 for 2013-2014, 2014-2015 and 2015-2016 was -2.0, -1.0 and 0.0 respectively using %FEV 1 in Knudson equation whereas the median change was -1.1, -0.9 and -0.3 respectively using %FEV 1 in the GLI equation. A statistically significant p-value (0.016) was only obtained when using %FEV 1 in Knudson equation extracted directly from spirometer machines. Conclusions: Although the trend of reduced year-to-year fall in %FEV 1 was robust, different data processing methods yielded varying results when year-to-year variation in %FEV 1 was compared using a standard related group non-parametric statistical test. Observational studies with year-to-year variation in %FEV 1 as an outcome measure should carefully consider and clearly specify the data processing methods used.

Sedation with Propofol for Bronchoscopy in Cystic Fibrosis Lung Transplant Recipients

INTRODUCTION

Flexible fiberoptic bronchoscopy (FFB) plays an important role in the surveillance of cystic fibrosis (CF) patients after lung transplantation (LTx). With rapid onset and clearance, propofol provides a safe and efficient method for sedation during FFB, yet sedation requirements for CF patients are not well described.

OBJECTIVES

Due to pharmacokinetic differences for other classes of drugs in CF patients, this study was performed to examine propofol requirements for sedation during bronchoscopy in lung transplant recipients with CF.

METHODS

A single-center retrospective cohort study was performed to examine propofol sedation requirements during outpatient surveillance. FFB procedures with transbronchial biopsy (TBB) in post-LTx recipients between 2009 and 2014 were conducted.

RESULTS

A total of 40 FFB procedures with TBB were performed 20 CF (11 females), 20 non-CF (11 females). Mean (± SD) age was 25.6 ± 9.2 (range 13-42) years and 22.2 ± 10.8 (range 11-39) years for the CF and non-CF groups, respectively. Propofol requirements were significantly higher in the CF patients compared to the non-CF patients. Mean (± SD) propofol dose for CF patients was 334 ± 86 versus 214 ± 88 mg for non-CF patients (p < 0.001). Mean (± SD) propofol dose per weight (mg/kg) was 6.5 ± 2.1 for CF patients versus 3.8 ± 1.6 for non-CF patients (p < 0.001).

CONCLUSIONS

Compared to a non-CF cohort, CF lung transplant recipients required higher dosages of propofol for sedation during FFB with TBB.

Lung Transplantation in Cystic Fibrosis and the Impact of Extracorporeal Circulation

INTRODUCTION

Lung disease is the major cause of death among cystic fibrosis (CF) patients, affecting 80% of the population. The impact of extracorporeal circulation (ECC) during transplantation has not been fully clarified. This study aimed to evaluate the outcomes of lung transplantation for CF in a single center, and to assess the impact of ECC on survival.

METHODS

We performed a retrospective observational study of all trasplanted CF patients in a single center between 1992 and 2011. During this period, 64 lung transplantations for CF were performed.

RESULTS

Five- and 10-year survival of trasplanted patients was 56.7% and 41.3%, respectively. Pre-transplantation supplemental oxygen requirements and non-invasive mechanical ventilation (NIMV) do not seem to affect survival (P=.44 and P=.63, respectively). Five- and 10-year survival among patients who did not undergo ECC during transplantation was 75.69% and 49.06%, respectively, while in those did undergo ECC during the procedure, 5- and 10-year survival was 34.14% and 29.87%, respectively (P=.001). PaCO₂ is an independent risk factor for the need for ECC.

CONCLUSIONS

The survival rates of CF patients undergoing lung transplantation in our hospital are similar to those described in international registries. Survival is lower among patients receiving ECC during the procedure. PaCO₂ is a risk factor for the need for ECC during lung transplantation.

Reemergence of Lower-Airway Microbiota in Lung Transplant Patients with Cystic Fibrosis

RATIONALE

Chronic lung infections are a hallmark of cystic fibrosis; they are responsible for progressive airway destruction and ultimately lead to respiratory death or the requirement for life-saving bilateral lung transplant. Furthermore, recurrent isolation of airway pathogens such as Pseudomonas aeruginosa in the allograft after transplant is associated with adverse outcomes, including bronchiolitis obliterans syndrome and acute infections. Little information exists on the impact of bilateral lung transplant on the lower-airway microbiota.

OBJECTIVES

To compare, at a microbiome and single-pathogen level (P. aeruginosa), the bacterial communities in pre- and post-transplant samples.

METHODS

We retrospectively accessed our biobank of sputum samples and sputum-derived bacterial pathogens for patients who had matched samples, including those who were clinically stable before transplant, those who had a pulmonary exacerbation before transplant, and those who had pulmonary exacerbation after transplant. We used 16S ribosomal RNA gene sequencing to characterize the lower-airway microbiome of 14 adult transplant patients with cystic fibrosis. Genotyping and phenotyping of P. aeruginosa isolates from 12 of these patients with matched isolates was performed.

MEASUREMENTS AND MAIN RESULTS

Although α-diversity (richness and evenness) of patient microbiomes was similar before and after transplant, β- diversity (core microbiome composition) measures stratified patients evenly into two groups with more similar and more dissimilar communities. P. aeruginosa strains isolated before transplant were found to reemerge in 11 of 12 patients; however, phenotypic variation was observed.

CONCLUSIONS

These findings indicate that recolonization by P. aeruginosa after transplant is almost always strain specific, suggesting a within-host source. The polymicrobial colonization of the airways after transplant does not always reflect the pretransplant sputum microbiota.

Lobar lung transplantation from deceased donors: a valid option for small-sized patients with cystic fibrosis

BACKGROUND

Small-sized patients with cystic fibrosis usually face long waiting times for a suitable lung donor. Reduced-size lung transplantation (LTx) was promoted to shorten waiting times. We compared donor and recipient characteristics and outcome in lobar ([L]) versus full-size ([FS]) lung recipients.

METHODS

Between July 1, 1991, and February 28, 2011, 535 isolated LTx were performed, including 74 in cystic fibrosis patients (8 L, 66 FS). Patients were followed up until September 2012.

RESULTS

[L] recipients were younger, smaller, and lighter. Sex, waiting times, and donor data (age, sex, height, weight, PaO2/FiO2, and ventilation time) were comparable. Cardiopulmonary bypass was used more often in [L]; cold ischemia was comparable for first lung but longer in [L] for second lung; implantation times were comparable. In-hospital mortality rate was 0% in [L] versus 3% in [FS]. Both intensive care unit and hospital stay were longer in [L]. Grade 3 primary graft dysfunction was more pronounced in [L] at T0 and at T48. FEV1 increased significantly in both groups from preoperative value. Bronchiolitis obliterans syndrome was absent in [L] and diagnosed in 18 patients in [FS], accounting for 6 of 15 late deaths. All [L] are still alive. No differences in survival were found between the groups.

CONCLUSIONS

Although hindered by a higher incidence of primary graft dysfunction, L-LTx is a viable option with excellent survival and pulmonary function comparable to FS-LTx.

Inflammation, oxidative stress, and cardiovascular disease risk factors in adults with cystic fibrosis

Cystic fibrosis (CF) represents one of a number of localized lung and non-lung diseases with an intense chronic inflammatory component associated with evidence of systemic oxidative stress. Many of these chronic inflammatory diseases are accompanied by an array of atherosclerotic processes and cardiovascular disease (CVD), another condition strongly related to inflammation and oxidative stress. As a consequence of a dramatic increase in long-lived patients with CF in recent decades, the specter of CVD must be considered in these patients who are now reaching middle age and beyond. Buttressed by recent data documenting that CF patients exhibit evidence of endothelial dysfunction, a recognized precursor of atherosclerosis and CVD, the spectrum of risk factors for CVD in CF is reviewed here. Epidemiological data further characterizing the presence and extent of atherogenic processes in CF patients would seem important to obtain. Such studies should further inform and offer mechanistic insights into how other chronic inflammatory diseases potentiate the processes leading to CVDs.

Pulmonary hypertension survival effects and treatment options in cystic fibrosis

PURPOSE OF REVIEW

This review discusses the current impact of pulmonary hypertension on the outcome and treatment of cystic fibrosis (CF).

RECENT FINDINGS

Pulmonary hypertension is commonly encountered in advanced lung diseases such as CF. The prevalence of pulmonary hypertension in CF patients varies based on disease severity and methodology used for diagnosis. Chronic alveolar hypoxia is the most likely cause. The majority of recent studies have shown worse survival in CF patients who develop pulmonary hypertension. The impact of pulmonary hypertension-specific therapies on symptomatology and outcomes in CF patients has not been well studied.

SUMMARY

Pulmonary hypertension is common in patients with CF and it occurs largely because of hypoxemia. The presence of pulmonary hypertension in patients with CF is likely associated with worse outcome; however, it remains unknown whether treatment with pulmonary hypertension-specific therapies would be beneficial.

Intra-operative extracorporeal membrane oxygenation use in pediatric lung transplantation--the Zurich experience

There is a lack of data regarding use of ECMO in children undergoing lung transplantation. We evaluated our experience of ECMO in pediatric lung transplant recipients. All patients (<18 yr) who underwent lung transplants between 1997 and 2011 were included (17 children; nine males; median age 16 yr), and the use of intra-operative ECMO evaluated. Transplant procedures were carried out with intra-operative ECMO in seven children (all bilateral lung transplants). Demographics of ECMO and non-ECMO patients were comparable. One child was already on ECMO pre-operative. Lung graft size reduction was undertaken in five ECMO and four non-ECMO cases, respectively. Five patients were taken off ECMO intra-operatively; the other patients were weaned off ECMO within 48 h post-operatively. Three-months survival was 100%. By 12 months post-transplantation, one patient each died in the ECMO and in the non-ECMO group. At the end of the study, six of seven ECMO cases were still alive (median survival 48.5 months); one patient required a retransplant at 53 months. Our small case series suggests that lung transplant procedures can be safely carried out in selected children on intra-operative ECMO support; however, our pediatric experience regarding this scenario is very limited but probably almost unique.

Aktueller Stand der Lungentransplantation

Die Lungentransplantation ist eine akzeptierte Behandlungsmethode für ausgewählte Patienten mit Lungenerkrankungen im Endstadium. Durch die Transplantation können die Überlebenszeit und die Lebensqualität der Betroffenen verbessert werden. Sowohl pulmonale als auch nichtpulmonale Komplikationen beeinträchtigen die Kurz- und die Langzeitergebnisse. Entscheidend bei der Therapie dieser Komplikationen sind das frühzeitige Erkennen und die schnelle Behandlung zur Verhinderung von sekundären Folgekomplikationen. Dieser Beitrag gibt einen Überblick über die häufigsten Probleme der Lungentransplantation, die im peri- und postoperativen Verlauf auftreten können.

Lung transplantation in patients with cystic fibrosis

Cystic fibrosis (CF) an autosomal recessive genetic disorder, affects many organs. The great majority of deaths occur due to respiratory failure after many years of chronic pulmonary infection. Despite recent progress in early detection by studies of genetic mutations and better understanding to treat nutritional and infectious states, lung transplantation is the CF treatment for most advanced cases. According to the International Society for Heart and Lung Transplantation (ISHLT) data, CF is the third most common reason for lung transplantation (16.8%) showing the best survival rate (60% at 5 years). We have described our experience in lung transplantation of CF patients between January 2000 and December 2011, reviewing medical charts of these patients were for gender, age, body mass index (BMI), comorbidities, disease duration, previous sputum gram stain, ischemic time, incidence of severe primary graft dysfunction (PGD Grade 3), intensive care unit (ICU) length of stay, and Kaplan-Meier survival. Among 150 lung transplantation, the 30 CF patients (20%) represented the second most common cause. The average age was 27.4 ± 9.2 years, with a slight predominance of males (n = 16; 53.3%). The average BMI was 18.9 ± 2.6. Most patients (60%) had pancreatic exocrine dysfunction. Also, 83.3% of patients showed a positive sputum culture for Pseudomonas, while Burkholderia cepacia was identified in only 4 patients (13.3%). The average time of the disease was 20.8 ± 9.7 years. All transplantation were bilateral with an average ischemic time of 472 ± 98.3 minutes and ICU length of stay of 9.9 ± 6.3 days. The survival rates at 1 and 5 years were 92% and 77%, respectively, corresponding to the best outcomes among underlying diseases, comparable with other worldwide series and better than the ISHLT reports. CF, the second most common cause for lung transplantation among our cases, showed the best survival rate among all causes. Our survival rate was comparable with other reports.

Comparative study of bronchial artery revascularization in lung transplantation

OBJECTIVE

Restoring dual blood supply to transplanted lungs by bronchial artery revascularization (BAR) remains controversial. We compared outcomes after lung transplantation performed with and without BAR.

METHODS

From December 2007 to July 2010, 283 patients underwent transplantation; 187 were 18 years or older, without previous or concomitant cardiac surgery. Of these patients, 27 underwent BAR in a pilot study to test success, safety, effectiveness, and teachability. A propensity score was generated to match BAR patients and 54 routine non-BAR patients. Follow-up was 1.3 ± 0.68 years.

RESULTS

BAR was angiographically successful in 26 (96%) of 27 patients. BAR and non-BAR patients had similar skin-to-skin time (P = .07) and postoperative hospital stays (P = .2), but more reoperations for bleeding (P = .002). Tracheostomy was performed in 9 (33%) of 27 BAR and 10 (19%) of 54 non-BAR patients (P = .2, log-rank). One BAR (3.7%) and 4 non-BAR (7.4%) patients required extracorporeal membrane oxygenation (P = .7). Airway ischemia was observed in 1 BAR (3.7%) versus 12 non-BAR (22%) patients (P = .03); anastomotic intervention was required in no BAR versus 8 non-BAR (15%) patients (P = .04). Hospital mortality was 1 of 27 versus 2 of 54 (P = .9). BAR patients had lower early biopsy tissue rejection grades (P = .008) and fewer pulmonary (P < .04) and bloodstream (P < .02) infections. Forced 1-second expiratory volume was similar (P > .2); 3 BAR versus 9 non-BAR patients developed bronchiolitis obliterans syndrome (BOS) (P = .14, log-rank). During follow-up, 4 BAR and 8 non-BAR patients died (P = .6, log-rank).

CONCLUSIONS

BAR is safe, with comparable early outcomes. Benefits of BAR include reduced airway ischemia and complications, lower biopsy tissue grades, fewer infections, and delay of BOS. A multicenter study is needed to establish these benefits.