Gastric motility and emptying assessment by magnetic resonance imaging after lung transplantation: correlation with gastric emptying scintigraphy.

PURPOSE: Gastroparesis is a frequent gastrointestinal complication after lung transplantation. Although gastric emptying scintigraphy (GES) is the standard technique to evaluate gastroparesis, magnetic resonance imaging (MRI) can also assess gastric motility and emptying. This study compared the results obtained by these two modalities. METHODS: Twenty-two lung transplant recipients underwent MRI and GES after ingesting a small pancake as a test meal. Parameters assessed on MRI included antral peristaltic wave velocity and frequency, and the ratios of gastric content volume at 15 and 35 min. GES parameters included retention rates (RR) in the stomach at 30, 60, and 120 min (RR30, RR60, and RR120) and half-time of emptying (T1/2) calculated by exponential curve fitting. Correlations between MRI and GES results were evaluated. RESULTS: Peristaltic wave velocity showed significant moderate negative correlations with RR120 (r = - 0.58, p < 0.05) and T1/2 (r = - 0.60, p < 0.05), indicating an association between reduced velocity and prolonged gastric emptying. Gastric content volume ratios on MRI showed significant moderate positive correlations with RR30 (r = 0.46, p < 0.05), RR60 (r = 0.60, p < 0.01), and T1/2 (r = 0.60, p < 0.01). There were no significant correlations between peristaltic wave frequency and GES parameters. MRI and GES parameters did not differ significantly between the six patients with and the 16 without upper gastrointestinal symptoms. CONCLUSIONS: MRI-based determinations of gastric motility and gastric emptying correlate with GES-based gastric emptying in lung transplant recipients, suggesting that MRI is useful for evaluating patients with gastroparesis.

Lung allocation score and health-related quality of life in Japanese candidates for lung transplantation.

OBJECTIVES: The lung allocation score (LAS) system has been implemented to reduce waiting list time and mortality in the USA, but it remains uncertain how the LAS would reflect the impairment in health-related quality of life (HRQOL), which is another lung transplantation treatment goal to be improved in addition to survival. We thus investigated the relationships of the LAS with mortality and HRQOL in Japanese lung transplantation candidates. METHODS: One hundred and two candidates for lung transplantation at Kyoto University Hospital between 2009 and 2013 were consecutively recruited to participate in this study. Their physiological measurements of pulmonary function and 6-min walking distance, as well as patient-reported measurements of HRQOL, dyspnoea and psychological status, were assessed. RESULTS: Among these 102 patients, 22 died during a mean follow-up of 11.6 months. The LAS was significantly correlated to mortality (P = 0.0026), although other physiological measurements were not. However, regarding its relationship with HRQOL, correlation coefficients between the LAS, Medical Outcomes Study 36-item short form and St George's Respiratory Questionnaire (SGRQ) were relatively low, with the highest at 0.31. Multivariate analyses showed that the LAS was less significantly related to the SGRQ total score than dyspnoea, and psychological status. CONCLUSIONS: The LAS was significantly related to mortality in lung transplant candidates in Japan, while, despite its multidimensional scoring, its relationship with health-related quality of life was only weak. Their severity assessment system may be more focused on patients' health and symptoms.

Forced oscillation technique as a non-invasive assessment for lung transplant recipients.

We usually use spirometry for the medical follow-up of respiratory mechanics after lung transplantation. However, especially in the first few post-operative weeks, it is easily affected by postoperative pain and the patient's co-operation during forced breathing effort. To avoid missing out on assessing pulmonary function, we perform non-invasive forced oscillation techniques on the patients who cannot perform forced breathing maneuvers. In this paper, we discuss the application of forced oscillation techniques on a patient with suspicion of acute lung rejection, whose spirometry could not be correctly performed and seemed to be unreliable. The respiratory impedance measurements had good correlation with the patient's clinical symptoms before and after steroid therapy. Thus, postoperative pulmonary function follow-up using forced oscillation technique was useful in assessing peripheral airway condition in critically ill patients, and may be able to detect acute rejection.