Uniportal approach as an alternative to the three-portal approach to video-assisted thoracic surgery for primary spontaneous pneumothorax

BackgroundIn recent years, uniportal video-assisted thoracic surgery (U-VATS) has been used for primary spontaneous pneumothorax (PSP). This study compared the perioperative outcomes of U-VATS and three-port VATS (3P-VATS) and sought to determine the risk factors for postoperative recurrence.MethodsFrom October 2010 to February 2017, 232 patients with PSP undergoing surgical treatment were enrolled in this study. The patients were divided into two groups: U-VATS (n=161) and 3P-VATS (n=71) depending on the period of surgery. Retrospective analysis of the perioperative results and the risk factors for recurrence was performed.ResultsBoth the operation time and duration of postoperative drainage were initially longer in the U-VATS group, but the difference gradually decreased such that ultimately there was no significant difference compared to the 3P-VATS group (P=0.10 and P=0.12, respectively). The duration of postoperative hospital stay and postoperative recurrence rate were not different between the two groups (P=0.084 and P=0.44, respectively). By multivariate analysis, the age (HR, 0.42, 95% CI: 0.24−0.72, P<0.01) and number of bullae (single vs. multiple: HR, 0.03, 95% CI: 0.002−0.54, P=0.02) were risk factors for recurrence.ConclusionsThe perioperative results and recurrence rate did not differ between the U-VATS and 3P-VATS groups, thereby demonstrating the non-inferiority of U-VATS. Postoperative risk factors for PSP recurrence were patient age and the number of bullae. Additional treatment may be needed to reduce recurrence in young patients with multiple bullae. Clinical registration number: The Institutional Review Board of Maebashi Red Cross Hospital (no. 2019-21).     

Chronic exposure to carbon monoxide in two elderly patients using a kotatsu,a traditional Japanese charcoal‐based heater

We report on two elderly patients with cognitive impairments, for whom chronic carbon monoxide (CO) exposure was suspected based on elevated carboxyhaemoglobin levels in their serum. On their initial visits, cognitive impairment and brain magnetic resonance imaging findings in both patients were compatible with the diagnosis of Alzheimer's‐type dementia. However, after discontinuation of the use of a kotatsu, a charcoal‐based heater, their serum carboxyhaemoglobin levels normalized and their physical symptoms resolved. Their cognitive function also slightly improved. The causal relationship between physical symptoms and cognitive impairment after chronic CO poisoning is uncertain; however, it is possible that chronic exposure to low CO levels exacerbated the clinical manifestation in our patients.     

Exercise responses during endurance testing at different intensities in patients with COPD

Endurance time on submaximal exercise tests is a sensitive measure in detecting changes after medical intervention and is used as an outcome in clinical trials, although there has been little discussion regarding the appropriate intensity. Therefore, we investigated whether there were differences in exercise responses between endurance tests at high versus moderate intensity, and analyzed which test was more appropriate. Thirty-seven patients with chronic obstructive pulmonary disease participated in the study. They performed cycle endurance tests at high and moderate submaximal workloads representing 80% and 60% of the maximum work rate reached on progressive cycle ergometry, respectively. Each type of exercise test was performed after inhaling salbutamol 400 microg, ipratropium bromide 80 microg or an identical placebo. Endurance time on the 80% endurance test was much shorter than on the 60% endurance test. The coefficients of variation for the endurance time were lower on the 80% test. Statistically significant improvements in the endurance time after bronchodilators in comparison to placebo were found only on the 80% test. When using the endurance time as an outcome, the high intensity endurance test is preferable to the moderate intensity endurance test, as the high intensity test demonstrated shorter exercise time, less variability and higher sensitivity.     

A simple and static preservation system for shipping retinal pigment epithelium cell sheets

The ability to move cells and tissues from bench to bedside is an essential aspect of regenerative medicine. In this study, we propose a simple and static shipping system to deliver tissue‐engineered cell sheets. Notably, this system is electronic‐device‐free and simplified to minimize the number of packing and opening steps involved. Shipping conditions were optimized, and application and verification of the system were performed using human iPS cell‐derived or fetal retinal pigment epithelium (RPE) cell sheets. The temperature of the compartments within the insulated container was stable at various conditions, and filling up the cell vessel with medium effectively prevented turbulence‐induced mechanical damage to the RPE cell sheets. Furthermore, no abnormal changes were observed in RPE morphology, transepithelial electrical resistance, or mRNA expression after transit by train and car. Taken together, our simple shipping system has the potential to minimize the costs and human error associated with bench to bedside tissue transfer. This specially designed regenerative tissue shipping system, validated for use in this field, can be used without any special training. This study provides a procedure for easily sharing engineered tissues with the goal of promoting collaboration between laboratories and hospitals and enhancing patient care.     

Pelvic lymphocyst infection associated with maternally inherited diabetes mellitus

A 45-year-old woman with 20-year history of diabetes mellitus was admitted to our hospital because of high fever and abdominal pain. Radical hysterectomy and bilateral pelvic lymphadenectomy had been performed 4 months before admission for invasive cervical cancer. On admission, elastic hard tumors were palpable in the lower abdomen. Laboratory examination showed positive C-reactive protein (CRP), anemia and renal dysfunction. Computed tomography (CT) revealed several lymphocysts in the pelvis. She was diagnosed with infection of pelvic lymphocysts. Since her mother also had diabetes associated with deafness, we examined mitochondrial DNA in leukocytes and detected an A to G transition at the nucleotide position of 3243 (A3243G mutation). She was diagnosed as maternally inherited diabetes mellitus and deafness (MIDD). Puncture of the cysts followed by administration of antibiotics resulted in marked improvement of symptoms and laboratory findings. This is a rare case of pelvic lymphocyst infection in a patient with a mitochondrial disorder. Although the exact mechanism of infection is not clear, MIDD may represent an unusual risk factor for infection, and further investigation is necessary to assess the influence of mitochondrial dysfunction on the immune system. Pelvic lymphocyst infection should be considered in the differential diagnosis of abdominal pain and fever in patients with MIDD after abdominal surgery.     

Retroperitoneal schwannoma between the inferior vena cava and the abdominal aorta resected by laparoscopic surgery: A case report

A 22‐year‐old woman presented with backache. Imaging analysis revealed a retroperitoneal tumor, 40 mm in diameter, surrounded by the abdominal aorta, inferior vena cava, caudate lobe of liver, and the left renal vein. The tumor consisted of multilocular cystic parts, and a solid part showed contrast enhancement. The possibility of malignancy could not be excluded, so we planned a laparoscopic tumorectomy. After placement of a transjugular vascular sheath for an occlusion balloon catheter in the inferior vena cava, the operation was performed with six ports. There was a strong fibrotic adhesion between the tumor and the abdominal aorta, with other weak adhesions. The tumor was successfully resected by a laparoscopic operation with minimal bleeding. The histopathological diagnosis was a benign schwannoma. This case demonstrates that a retroperitoneal tumor adjacent to major vessels can be resected safely by laparoscopic surgery if the surgeon is especially careful of the possibility of accidental bleeding.