Swallowing and laryngeal complications in lung and heart transplantation: Etiologies and diagnosis

A Phase 1, Open-Label, Randomized, Two-Part Study in Healthy Adult Volunteers to Evaluate the Bioavailability of the Maribavir Powder for Oral Suspension, as Well as Food Effect and Impact of Rabeprazole

The relative bioavailability and impact of food and the proton pump inhibitor rabeprazole on the pharmacokinetics of a maribavir powder-for-oral-suspension formulation was investigated in a Phase 1 open-label study in healthy adult volunteers. A single 200-mg maribavir dose was administered as the commercial tablet (Treatment A), powder formulation (Treatment B), or powder formulation with a high-fat/high-calorie meal (Treatment C) in Part 1, and as the powder formulation alone (Treatment D) or following administration of rabeprazole 20 mg once daily for 5 days (Treatment E) in Part 2. Maribavir maximum plasma concentration following Treatment B was 18% lower versus Treatment A, whereas the area under the concentration-time curve (AUC) from time 0 to the last quantifiable concentration or infinity were similar. Maribavir maximum plasma concentration, AUC from time 0 to the last quantifiable concentration, and AUC from time 0 to infinity were reduced by 42%, 18%, and 18% (Treatment C vs Treatment B), and by 51%, 30%, and 11% (Treatment E vs Treatment D), respectively. A clinically significant reduction in maribavir exposure is not expected when maribavir powder formulation is taken with food or proton pump inhibitors. Participants assessed the powder for oral suspension as easy to swallow and having an acceptable taste/texture. Safety profiles for maribavir formulations in this study were consistent with those previously published.

Incidence and Risk Factors for Clinically Significant Oropharyngeal Dysphagia After Lung Transplantation

Aspiration is one of many risk factors for chronic lung allograft dysfunction, which continues to limit survival in lung transplant recipients. Oropharyngeal dysphagia (OPD) occurring after lung transplant surgery increases the risk of antegrade aspiration. While the incidence and risk factors for OPD have been well described in cardiac surgery, there is less known in the lung transplant population. The aim of this retrospective, single-center study was to determine the incidence of clinically significant OPD in lung transplant recipients and to identify patient and procedural risk factors for OPD in this population. A total of 158 lung transplant recipients who underwent postoperative fiberoptic endoscopic evaluation of swallowing (FEES) were included in the study. The incidence of OPD was 67.1% (106/158) with 29.8% (47) having a complete absence of swallowing function. Female sex, cardiopulmonary bypass, duration of intubation, and an increased number of transesophageal echocardiography (TEE) clips were associated with OPD. The incidence of OPD in this study is consistent with the limited data available in lung transplant literature, and higher than that of general cardiac surgery. An increased number of acquired TEE clips is a novel OPD risk factor in this population and a modifiable target for future intervention.

Effect of Food, Crushing of Tablets, and Antacid Coadministration on Maribavir Pharmacokinetics in Healthy Adult Participants: Results From 2 Phase 1, Open-Label, Randomized, Crossover Studies

The effect of food composition, tablet crushing, and antacid coadministration on maribavir pharmacokinetics was assessed in 2 Phase 1 studies in healthy adults. In the first, a single maribavir 400-mg dose was administered under fasting conditions, with a low-fat/low-calorie or a high-fat/high-calorie meal. In the second, a single maribavir 100-mg dose was administered under fasting conditions, as a crushed tablet, or as a whole tablet alone or with an antacid. The 90% confidence intervals of the geometric mean ratios were within 80%-125% for area under the concentration-time curve (AUC), but not for maximum plasma concentration (Cmax) for low-fat/low-calorie and high-fat/high-calorie meals versus fasting or for whole tablet with antacid versus whole tablet alone. The 90% confidence intervals of the geometric mean ratios for AUC and Cmax were within 80%-125% for crushed versus whole tablet. Maribavir median time to Cmax value in plasma under fed conditions was delayed versus fasting conditions, but there was no statistical difference for crushed versus whole tablet or with versus without antacid. As the antiviral efficacy of maribavir is driven by AUC but not Cmax, findings suggest that maribavir can be administered with food or antacids or as a crushed tablet.

Gastrointestinal complications in pediatric lung transplant recipients: Incidence, risk factors, and effects on patient outcomes

BACKGROUND

Gastrointestinal (GI) complications in lung transplant recipients can occur any time during the post-operative period, leading to prolonged morbidity and mortality. Despite the negative association between GI complications and patient outcomes, little is known about their incidence and risk factors for their development in pediatric lung transplant recipients.

METHODS

We performed a retrospective chart review at one pediatric tertiary center to describe the frequency of GI complications in lung transplant recipients. We identified potential risk factors for the diagnosis of gastroparesis, gastroesophageal reflux disease (GERD) and aspiration in the post-transplant period. Lastly, we investigated the association of these complications with mortality and graft survival.

RESULTS

84.3% of lung transplant recipients experienced at least one GI complication in the post-transplant period. Gastroparesis (52.9%), GERD (41.2%), and oropharyngeal dysphagia/laryngeal penetration (33.3%) were the most common complications diagnosed. Post-operative opioid exposure was a risk factor for gastroparesis, with the odds increasing 3.0% each day a patient was prescribed opioids (p = .021). The risk of death or retransplant in individuals who experienced gastroparesis was 2.7 times higher than those not diagnosed with gastroparesis (p = .027).

CONCLUSION

Exposure to opioids in the post-operative period is a risk factor for gastroparesis and a prolonged hospitalization placed patients at risk for aspiration. Gastroparesis was associated with increased patient mortality and graft failure, while aspiration and GERD had no effect on long term outcomes. Future prospective studies investigating the relationship between opioid use and the development of a gastroparesis are necessary to improve patient outcomes.

Heart Transplantation-Postoperative Considerations

Heart transplantation (HT) remains the best treatment of patients with severe heart failure who are deemed to be transplant candidates. The authors discuss postoperative management of the HT recipient by system, emphasizing areas where care might differ from other cardiac surgery patients. Working together, critical care physicians, heart transplant surgeons and cardiologists, advanced practice providers, pharmacists, transplant coordinators, nursing staff, physical therapists, occupational therapists, rehabilitation specialists, nutritionists, health psychologists, social workers, and the patient and their loved ones partner to increase the likelihood of a successful outcome.

Prevalence and clinical predictors of dysphagia after heart transplantation

INTRODUCTION

Dysphagia is a common complication after heart transplantation (HTPL), but few studies exist on dysphagia after HTPL, and the prevalence is unknown. The objective of our current study was to establish the prevalence and risk factors for dysphagia after HTPL and to classify its characteristics through Videofluoroscopic Swallowing Studies (VFSS).

METHODS

The recipients of HTPL carried out at a single center from January 2011 to November 2019 were assessed retrospectively. Dysphagia was evaluated by a bedside swallowing exam and VFSS to evaluate for evidence of aspiration. The duration of ventilator and preoperative extracorporeal membrane oxygenation (ECMO) support, intensive care unit, hospital stay, the progress of oral feeding after surgery, the presence of a tracheostomy, and vocal cord palsy were analyzed. On the third and seventh days following surgery, we looked at the relationship between risk factors and oral feeding progress, respectively. Additionally, we contrasted these risk variables with the no penetration/aspiration (PA) group and the PA group on VFSS.

RESULTS

Among the study cohort of 421 patients, 222 (52.7%) patients had access to oral feeding on the third day of surgery. The number of patients who underwent VFSS due to clinically suspected dysphagia was 96 (22.8%). Of these, 54 (56.2%) had aspiration or penetration (PA group), while 42 (43.8%) had no abnormal findings (No-PA group). In the multivariable regression model, preoperative ECMO support, vocal cord abnormalities, tracheostomy, and emergent need for HTPL were identified as independent risk variables for oral feeding progress on postoperative days (PODs) 3 and 7. Among these factors, preoperative ECMO support had the highest odds ratio (OR) at PODs 3 (OR: 4.73, CI: 1.997, 11.203, p < .001) and 7 (OR: 5.143, CI: 2.294, 11.53, p < .001).

CONCLUSION

We identified the prevalence and potential risk factors for postoperative dysphagia in this retrospective analysis of 421 heart transplant recipients. The pathophysiology of postoperative dysphagia was multifactorial, and it was more common than the incidence after general cardiothoracic surgery.

Utilization of Instrumentation in Swallowing Assessment of Surgical Patients during COVID-19

The aim of this study is to describe a measured return to instrumental dysphagia assessments for our vulnerable surgical patient population, such that best practice patterns could be resumed and our staff kept safe from transmission of COVID-19. A retrospective medical record review provided data on clinical practice patterns of swallowing assessment in an at-risk surgical patient population. Outcomes of this study support protocols that allow clinicians to safely resume the use of instrumental assessment and return to best practice in dysphagia assessment for our surgical patient population.

A prospective examination of swallow and cough dysfunction after lung transplantation

OBJECTIVES

Swallow and cough dysfunction are possible surgical complications of lung transplantation (LT). We examined voluntary cough strength, sensorimotor reflexive cough integrity, and swallow-related respiratory rate (RR) across swallowing safety and aspiration response groups in recovering LT recipients.

METHODS

Forty-five LT recipients underwent flexible endoscopic evaluation of swallowing indexed by the validated Penetration Aspiration Scale. RR before and after a 3-ounce water drinking task was measured. Voluntary and reflexive cough screening were performed to index motor and sensory outcomes. T-tests, one-way ANOVAs, and chi-square (odds ratios) were used.

RESULTS

60% of patients exhibited laryngeal penetration (n = 27) and 40% demonstrated tracheal aspiration (n = 18); 72% (n = 13) demonstrated silent aspiration. Baseline RR was higher in aspirators versus non-aspirators (26.5 vs. 22.6, p = 0.04) and in silent aspirators compared to non-silent aspirators (27.9 vs. 20.7, p = 0.01). RR change post-swallowing did not differ between aspiration response groups; however, it was significantly higher in aspirators compared to non-aspirators (3 vs. -2, p = 0.02). Compared to non-silent aspirators, silent aspirators demonstrated reduced voluntary cough peak expiratory flow (PEF; 166 vs. 324 L/min, p = 0.01). PEF, motor and urge to cough reflex cough ratings did not differ between aspirators and non-aspirators. Silent aspirators demonstrated a 7.5 times higher odds of failing reflex cough screening compared to non-silent aspirators (p = 0.07).

CONCLUSIONS

During the acute recovery period, all LT participants demonstrated some degree of unsafe swallowing and reduced voluntary cough strength. Silent aspirators exhibited elevated RR, reduced voluntary cough physiologic capacity to defend the airway, and a clinically distinguishable blunted motor response to reflex cough screening.

Esophageal Dysfunction in Post-lung Transplant: An Enigma

The prevalence of lung transplants has increased over the years, albeit with a low survival rate amongst all solid organ transplants, including liver and heart transplantation. Microaspiration is one of the primary mechanisms that has been implicated in the pathogenesis of lung injury following lung transplants. Of late, esophageal dysfunction such as gastroesophageal reflux and esophageal hypercontractility is often noted post-lung transplant. However, reflux is associated with chronic allograft lung injury such as bronchiolitis obliterans syndrome, which is one of the predictors for long-term survival in this specialized population. Its role in acute lung injury post-lung transplant is still being explored. This review critically examines the salient points which provide the current understanding of the characteristics, pathophysiology, and implications of esophageal dysfunction following lung transplant.

Postoperative management of children after lung transplantation

Pediatric lung transplantation is a highly specialized treatment option at a select few hospitals caring for children. Advancements in surgical and medical approaches in the care of these children have improved their care with only minimal improvement in outcomes which remain the lowest of all solid organ transplants. A crucial time period in the management of these children is in the perioperative period after performance of the lung transplant. Supporting allograft function, preventing infection, maintaining fluid balance, achieving pain control, and providing optimal respiratory support are all key factors required for this highly complex pediatric patient population. We review commonly encountered complications that these patients often experience and provide strategies for management.