Should lung transplant recipients routinely perform airway clearance techniques? A randomized trial

Alterations in Pulmonary Physiology with Lung Transplantation

Lung transplant is a treatment option for patients with end-stage lung diseases; however, survival outcomes continue to be inferior when compared to other solid organs. We review the several anatomic and physiologic changes that result from lung transplantation surgery, and their role in the pathophysiology of common complications encountered by lung recipients. The loss of bronchial circulation into the allograft after transplant surgery results in ischemia-related changes in the bronchial artery territory of the allograft. We discuss the role of bronchopulmonary anastomosis in blood circulation in the allograft posttransplant. We review commonly encountered complications related to loss of bronchial circulation such as allograft airway ischemia, necrosis, anastomotic dehiscence, mucociliary dysfunction, and bronchial stenosis. Loss of dual circulation to the lung also increases the risk of pulmonary infarction with acute pulmonary embolism. The loss of lymphatic drainage during transplant surgery also impairs the management of allograft interstitial fluid, resulting in pulmonary edema and early pleural effusion. We discuss the role of lymphatic drainage in primary graft dysfunction. Besides, we review the association of late posttransplant pleural effusion with complications such as acute rejection. We then review the impact of loss of afferent and efferent innervation from the allograft on control of breathing, as well as lung protective reflexes. We conclude with discussion about pulmonary function testing, allograft monitoring with spirometry, and classification of chronic lung allograft dysfunction phenotypes based on total lung capacity measurements. We also review factors limiting physical exercise capacity after lung transplantation, especially impairment of muscle metabolism. © 2023 American Physiological Society. Compr Physiol 13:4269-4293, 2023.

Preoperative risk factors for successful extubation or not after lung transplantation

Background

The purpose of this study was to uncover preoperative risk factors for extubation failure or re-intubation for patients undergoing lung transplant (LTx).

Methods

We performed a retrospective case-control study of LTx from our center between January 2017 and March 2019. Demographic and preoperative characteristics were collected for all included patients. Univariable analysis and multivariable logistic regression were used to analyze risk factors of postoperative unsuccessful extubation following LTx.

Results

Among 107 patients undergoing first LTx investigated, 74 (69.16%) patients who were successfully liberated from mechanical ventilation (MV), and 33 (30.84%) patients who were unsuccessful extubation, which 18 (16.82%) patients suffered from reintubation. associated preoperative factors for unsuccessful extubation following LTx included preoperative extracorporeal membrane oxygenation (ECMO) support [OR =4.631, 95% confidence interval (CI): 1.403–15.286, P=0.012], the preoperative ability of independent expectoration (OR =4.517, 95% CI: 1.498–13.625, P=0.007), the age older than 65-year-old (OR =4.039, 95% CI: 1.154–14.139, P=0.029), and receiving the double lung and heart-LTx (OR =3.390, 95% CI: 0.873–13.162, P=0.078; and OR =16.579, 95% CI: 2.586–106.287, P=0.012, respectively). Further, we investigated the preoperative predicted factors for reintubation. Only the preoperative ECMO remained a significant predictor of re-intubation (OR =4.69, 95% CI: 1.56–15.286, P=0.012).

Conclusions

Preoperative independent sputum clearance, preoperative ECMO, older than 65-year-old, and double lung or heart-LTx were four independent risk factors for unsuccessful extubation. Moreover, preoperative ECMO was the only independent risk factor for reintubation.

Inhaled hypertonic saline after pediatric lung transplant-Caution required?

Management of pulmonary infection following lung transplant is multifaceted and includes respiratory physiotherapy. Inhaled hypertonic saline (HTS) has been introduced as an adjunct to physiotherapy in pediatric transplant patients. There are no published studies investigating the use of HTS in this population. This study aimed to evaluate the effect of inhaled HTS, in the acute post-operative period, in pediatric lung transplant patients. A retrospective case-note review was completed at a single UK pediatric transplant center. An intervention group who received HTS was compared to a historical control group. Participants were frequency matched for age, gender, and diagnosis (14 per group); median age in years was 13.7(IQR 12.7-15.3) in the controls and 14.8(IQR 12.4-16.1) in the intervention group. Primary outcome was the requirement of invasive and non-invasive ventilation. Secondary outcomes included oxygen use and length of stay. Median days of invasive ventilation were shorter in the control group (1, 95% CI 1-1) compared to the intervention group (2, 95% CI 1-2.5) (P < .05). Days of non-invasive ventilation and oxygen were higher in the HTS group, but this was not statistically significant. The controls displayed shorter median length of stay (23 days, 95% CI 20-24) compared to the intervention group (31 days, 95% CI 24.5-39) (P < .05). The results of this small study provide uncertainty regarding the safety of inhaled hypertonic saline after lung transplant. There was a trend of poorer acute outcomes in patients who received HTS. However, the findings should be interpreted with caution and further investigation using larger samples is required.