Current situation of management of spontaneous pneumothorax in Japan: A cross-sectional cohort study.

BACKGROUND: Limited epidemiological information is available on spontaneous pneumothorax. To address this gap, the Japan Society for Pneumothorax and Cystic Lung Disease (JSPCLD) conducted a nationwide retrospective survey to investigate the current epidemiology of spontaneous pneumothorax in Japan. METHODS: In this study, we conducted a retrospective cross-sectional cohort study to demonstrate the clinical features of spontaneous pneumothorax in one year from April 2019 to March 2020, compare patient characteristics and treatment outcomes between primary (PSP) and secondary spontaneous pneumothorax (SSP), and investigate the risk factors associated with in-hospital mortality among patients with SSP. RESULTS: A total of 1784 patients from 28 institutions were enrolled in the study, with PSP observed in 956 cases (53.6%) and SSP in 817 cases (45.8%). The age distribution showed a biphasic peak caused by the different peaks between PSP and SSP. In-hospital mortality occurred in 42 cases (2.4%) among all patients, with 0 cases (0%) in PSP and 42 cases (5.1%) in SSP. Multivariable analyses revealed that interstitial pneumonia as an underlying disease (odds ratio: 2.4700, 95% confidence interval: 1.1100 to 5.4800, p = 0.0269), performance status≧3 (odds ratio: 7.3900, 95% confidence interval: 3.1900 to 17.2000, p < 0.0001), and lower value of serum albumin on admission (odds ratio: 0.4060, 95% confidence interval: 0.2140 to 0.7690, p = 0.0057) were significantly associated with in-hospital mortality among patients with SSP. CONCLUSIONS: SSP patients with poor baseline conditions are at a higher risk for in-hospital mortality. It is crucial to provide close and meticulous management for SSP patients with compromised conditions.

A retrospective multi-institutional survey of characteristics of surgically treated spontaneous hemopneumothorax patients.

OBJECTIVE: The Japan Society for Pneumothorax and Cystic Lung Disease conducted a nationwide retrospective survey to identify correlations between the timing of surgical intervention and the incidence of transfusion, and to examine the factors contributing to the need for transfusion among clinical features in surgically treated spontaneous hemopneumothorax (SHP) patients. METHODS: We analyzed the characteristics and perioperative results of patients with SHP who underwent thoracoscopy or thoracotomy between April 2009 and March 2019. RESULTS: From 17 institutions, 171 cases were enrolled in this study. Receiver-operating characteristic curve analyses for the incidence of transfusion and waiting time before the operation revealed an area under the curve of 0.54 (95% confidence interval [CI] 0.44-0.64). Therefore, we did not compare the clinical features using a cutoff value of waiting time before the operation. More than 80% of the patients underwent surgical treatment within 24 h from admission. Multivariate analysis revealed that the total volume of hemorrhage was the only significant factor contributing to the incidence of transfusion (p = 0.00011, odds ratio: 0.03, 95% CI 0.0051-0.18). Moreover, multivariate analyses revealed that the waiting time before the operation was a contributing factor for prolonged total hospitalization (p < 0.0001, estimated regression coefficient: 0.036, 95% CI 0.027-0.045). CONCLUSION: In SHP patients, a reduction in the waiting time before the operation significantly contributed to not the avoidance of transfusion but a reduction in total hospitalization time. In addition, transfusion was performed depending on the volume of blood loss.

[Acute Mediastinitis].

Acute mediastinitis is a deep thoracic infection. In particular, descending necrotizing mediastinitis (DNM) is serious and potentially fatal, however, the initial symptoms are often not severe. It is caused by prolonged oropharyngeal or odontogenic infections such as pharyngitis, tonsillitis, and dental caries. The most common pathogens are Gram-positive cocci and anaerobes, and patients often have underlying medical conditions such as diabetes mellitus, steroid use, and chronic renal failure. Surgical drainage is necessary for treatment, and surgery should be performed as soon as possible after diagnosis. The mortality rate of DNM was initially reported to be more than 40%, but has improved to less than 20% in recent years. Proper judgment and appropriate surgery have contributed to the improvement of the life-saving rate.

Retrolaminar versus epidural block for postoperative analgesia after minor video-assisted thoracic surgery: a retrospective, matched, non-inferiority study.

BACKGROUND: The role of thoracic epidural analgesia (TEA) for postoperative analgesia after video-assisted thoracic surgery (VATS) is still controversial. Some studies have reported the efficacy of ultrasound-guided retrolaminar block (RLB) for the postoperative management of pain after chest wall surgery. The purpose of this study was to compare the postoperative analgesic efficacy and adverse effects of ultrasound-guided RLB with those of TEA in patients undergoing minor VATS procedures. METHODS: A total of 192 relevant records of patients were enrolled in this study. We reviewed electronic medical records of patients undergoing minor VATS procedures under general anesthesia. The primary outcome was the median differences in the numerical rating scale (NRS) scores during rest between the groups at the morning of postoperative day 1 (POD 1m). A propensity-matched analysis incorporating preoperative variables was used to compare the efficacy of postoperative analgesia in two groups. RESULTS: Overall, 94 patients were identified for analysis. Propensity score matching resulted in 47 patients in each group. There were no significant differences in the NRS scores between the two groups. The median differences in NRS scores during rest between the two groups at POD 1m were under 1, which indicates non-inferiority of RLB. There were no significant differences in the incidence of adverse effects and rescue dose of analgesic consumption between the two groups. CONCLUSIONS: The analgesic effects of continuous ultrasound-guided RLB were non inferior to those of TEA for minor VATS procedures.

Preliminary experimental outcomes of induced hypercapnia in treatment of obstinate singultus.

BACKGROUND: Our team found that abolishing the venous-arterial CO2 gradient can cease singultus (hiccups), in which the CO2 pressure in blood reaches no less than 50 mmHg. In order to precisely investigate the target level as a preliminary study, we made a combination gas consisting of 10% CO2 and 90% O2 to generate the conditions instantly and safely. METHODS: Thirty-five cases consisting of 26 patients with long-term chronic singultus were treated using the gas. The group consisted of 21 males and 5 females with mean singultus duration of 8.0±13.1 years. A standard oxygen mask was used for delivery of the gas to the patients, and patients breathed in the gas until they felt relief. The duration of the procedure was measured from the beginning to the point at which singultus ceased. A blood test was performed to measure the partial pressure of CO2 in venous blood at the point at which singultus ceased. RESULTS: Singultus ceased in all patients in a mean time of 5.3±1.5 minutes, with complete recurrence observed in two cases. The mean partial pressure of CO2 in the venous blood at the point the singultus stopped was 60.8±6.8 mmHg. No life-threatening complications were found in any patient. CONCLUSIONS: One of the definitive conditions for ceasing singultus is acute CO2 retention in the body, the target of which is around 60 mmHg of CO2 in venous blood. We believe that targeting acute hypercapnia can always stop singultus, although further neuroscientific investigation is necessary to reveal the physiological mechanism.

[Pulmonary Mucormycosis with Reversed Halo Sign on Computed Tomography of Patient with Leukemia].

The patient was a male in his 60s, who had undergone bone marrow transplantation because of lymphoblastic leukemia. He suffered from chest pain two weeks after the transplantation. A chest computed tomography(CT) showed reversed halo sign( RHS) in the right upper lobe of the lung. A bronchoscopic lung biopsy revealed mycelia, and the patient was diagnosed with pulmonary mucormycosis. Although antifungal drugs were administered, no significant improvements were observed. A right upper lobectomy of the lung was successfully performed, and no postoperative complications occurred. Pathological examination found nodular lesions with extensive necrotic foci inside, and inflammatory granulation tissue and mucormycosis with hyphae (+) were found through Grocott staining. RHS in leukemia patients with neutropenia is specific to pulmonary mucormycosis. Pulmonary mucormycosis is a life-threatening disease, and urgent treatment intervention including surgical treatment is advisable.

Pneumothorax in teenagers: reducing recurrence through resection of superior segment of lower lobe.

BACKGROUND: Spontaneous pneumothorax in young patients is characterized by a high recurrence rate. We retrospectively investigated causes of recurrence and effective surgical methods to improve this statistic, in particular through resection of the superior segment of the lower lung lobe (S6a). METHODS: From April 2011 to September 2017, we performed 146 operations for 126 lateral side pneumothoraces in patients 20 years of age or younger (105 males and 7 females, mean age 17.2 years) at our institution. Two groups-one with patients who underwent both apical bullectomy and S6a resection (the S6a group), and the other with patients who underwent only apical bullectomy with apical reinforcement using an absorbable mesh sheet (the AB group)-were statistically compared in terms of recurrence rate. RESULTS: A significant difference was found between the S6a group and the AB group in terms of the number of S6a recurrences (0 vs. 8 cases, respectively; P=0.025), although there was no significant difference between the two groups in terms of the total recurrence rate (16.1% vs.18.6%, respectively). Pathological examination revealed that 55 of the 56 (98.2%) S6a specimens already contained asymptomatic, non-ruptured bullae or microscopic bullous lesions at the time of the initial operation. CONCLUSIONS: In addition to the apex, the S6a often involves lesions responsible for pneumothorax recurrence. To reduce this recurrence in teenage patients, we suggest that S6a resection be concomitantly performed in the initial operation-even if there are no macroscopically visible blebs on the S6a.

Medullar impairment resolves hiccups.

BACKGROUND: In a previous article we reported the time that hiccups stop as the instant when CO2 levels in both expiratory gas (EtCO2) and inspiratory gas (InspCO2) reach approximately 50 mmHg. To support our findings, in this article we aim to clarify the precise values of the CO2 level in arterial blood (PaCO2) and venous blood (PvCO2) during plastic bag rebreathing. METHODS: A healthy male volunteer was asked to perform a rebreathing experiment using a 20 L air-filled plastic bag. During the experiment, his blood oxygen saturation level (SpO2), EtCO2 and InspCO2 were measured until the volunteer gave up. PaCO2 and PvCO2 were measured at the following four points: P0, when the rebreathing started; P1, when both EtCO2 and InspCO2 indicated the same value; P2, when both reached 50 mmHg; and P3, when SpO2 dropped to 90%. RESULTS: InspCO2 increased from the beginning and showed the same value as EtCO2 at P1. PaCO2 at P1 was almost the same value as both InspCO2 and EtCO2. After P1, InspCO2, EtCO2 and PaCO2 increased at the same rate, and at P2, they reached the level of PvCO2. After P2, all four markers continued to show the same value as they gradually increased. CONCLUSIONS: Creating conditions inside the body in which PaCO2 increases to the same level as PvCO2 will stop hiccups consistently. Although other physiological pathways to stop hiccups may exist, for a successful outcome it is important that the balance of power between the cerebellum and the medulla is drastically altered.

CO2 retention: The key to stopping hiccups.

BACKGROUND: While investigating the mechanisms behind hiccups, our team discovered what could be the sufficient physiological conditions for terminating even persistent cases. METHODS: To investigate the role of CO2 retention, a healthy male volunteer was asked to perform three kinds of rebreathing experiments using different materials: (I) a 20 L air-filled plastic bag, (II) a 20 L air-filled plastic bag with a 1.5 × 1.5 cm hole and (III) a 20 L oxygen-filled plastic bag. During each experiment, CO2 level upon expiration (EtCO2 ) and inspiration (InspCO2 ) were measured until the volunteer gave up. Once the safety of this manoeuvre was demonstrated with the volunteer, we performed the technique using the materials from experiment (I) on two actual patients with persistent hiccups. RESULTS: In experiments (I) and (III), InspCO2 increased from the beginning and reached almost the same level as EtCO2 after 90 seconds. Both levels continued simultaneously increasing, finally reaching 56 mm Hg in (I) and 79 mm Hg in (III), respectively. In (II), both increased; however, after 120 seconds, EtCO2 plateaued at 47 mm Hg and InspCO2 at 37 mm Hg. In the actual patients, both CO2 levels reached the same value of 35.9 mm Hg at 60 seconds and 37.0 mm Hg at 90 seconds, and hiccups stopped at 195 seconds and at 359 seconds when EtCO2 reached 50 mm Hg and 53 mm Hg, respectively. CONCLUSION: The study determined that to successfully obstruct the mechanisms causing hiccups, it is necessary that the level of InspCO2 not only increases at the same level as EtCO2 , but also reaches approximately 50 mm Hg.

Postoperative pain in thoracic surgery: re-evaluating the benefits of VATS when coupled with epidural analgesia.

BACKGROUND: In order to evaluate the reduced postoperative pain of complete video-assisted thoracoscopic surgery (cVATS), a study was conducted to compare acute postoperative pain between cVATS and open thoracotomy employing continuous epidural analgesia (EA). METHODS: A total of 62 patients, 49 males and 13 females with a mean age of 54.8 years, who had undergone thoracic surgery at our institution from November 2013 to June 2015 were enrolled in this study. We statistically investigated differences in the intensity of postoperative pain between cVATS with or without EA and between cVATS and open thoracotomy under EA. The degree of pain was measured using a visual analog scale, nine times for three days after the surgery. RESULTS: The mean postoperative pain scores were stronger in the cVATS without EA group than in the group treated with EA at every single observation point, although there were no significant differences. When employing EA, no significant differences were found between cVATS and open thoracotomy. CONCLUSIONS: The use of EA may overshadow the benefits of using cVATS over open thoracotomy.

A teleconference with three-dimensional surgical video presentation on the 'usual' Internet.

Endoscopic surgery employing three-dimensional (3D) video images, such as a robotic surgery, has recently become common. However, the number of opportunities to watch such actual 3D videos is still limited due to many technical difficulties associated with showing 3D videos in front of an audience. A teleconference with 3D video presentations of robotic surgeries was held between our institution and a distant institution using a commercially available telecommunication appliance on the 'usual' Internet. Although purpose-built video displays and 3D glasses were necessary, no technical problems occurred during the presentation and discussion. This high-definition 3D telecommunication system can be applied to discussions about and education on 3D endoscopic surgeries for many surgeons, even in distant places, without difficulty over the usual Internet connection.

Ten cases of resected solitary pulmonary metastases arising from gastric cancer.

BACKGROUND: Because carcinomatous lymphangitis and carcinomatous pleuritis are the usual forms of metastasis associated with gastric cancer, resection of solitary pulmonary metastases arising from gastric cancer is rarely performed. To clarify the characteristics of pulmonary metastases from gastric cancer, we investigated patients who underwent resection of metastatic solitary lung tumors arising from gastric cancer. METHODS: Between October 2003 and October 2012, 10 patients underwent pulmonary metastasectomy for metastatic gastric cancer at our institution. We retrospectively evaluated features of the primary gastric cancer and the clinicopathological features of the pulmonary metastases in these cases. RESULTS: 70% of the patients had stage II disease. Lymphatic invasion was observed in all cases of primary gastric cancer. The method of pulmonary resection was partial resection in 5 cases, segmentectomy in 1, and lobectomy in 4. On histopathological examination, immunohistochemical staining was negative for thyroid transcription factor-1 and napsin A in all cases. Patients who underwent resection of pulmonary metastases arising from gastric cancer had a good prognosis: the 4-year survival rate was 75%. CONCLUSIONS: Carefully chosen patients have a good opportunity to obtain benefits from resection of pulmonary metastases arising from gastric cancer.

Efficacy of arginine supplementation for the treatment of air leakage.

BACKGROUND: Recently, the role of the amino acid arginine in wound healing has been emphasized. We studied whether postoperative enteral arginine supplementation can contribute to the resolution of prolonged air leakage after lung resections. METHODS: 42 patients undergoing lung resection at our institutions from 2009 to 2012 were enrolled in this study. In these patients, continuous air leakage in the expiratory phase was identified on the day of surgery and on the following day. The patients were divided into 2 groups; the first group included 21 patients consuming 3 packs of an arginine supplement beverage daily postoperatively, and the second group (control) included 21 patients who did not consume any additional supplements. The durations of air leakage and chest tube drainage were compared between the two groups. RESULTS: The mean durations of air leakage and chest tube drainage were shorter in the arginine supplementation group (4.4 vs. 6.7 days, p = 0.010; 6.5 vs. 8.3 days, p = 0.042, respectively). CONCLUSION: Postoperative enteral arginine supplementation may contribute to stopping air leaks after lung surgery.

Outcomes of surgery in lung cancer patients with schizophrenia.

PURPOSE: There are very few reports regarding the outcome of lung cancer surgery in patients with schizophrenia, and the clinical features of such patients are still unclear. METHODS: From 2004 to 2012, 11 lung cancer patients (six male, five female; mean age, 62.7 years) with schizophrenia underwent lung resections at our institutions. All patients had been institutionalized because they were unable to live independently at home. We retrospectively evaluated their postoperative clinical outcomes and long-term results. RESULTS: Ten of the 11 patients had comorbidities, such as diabetes mellitus and chronic obstructive pulmonary disease. Preoperatively, two patients had a history of treatment for other primary cancers in other organs, and one was on hemodialysis. A lobectomy was performed in nine patients, a segmentectomy in one, and a partial resection in one. There were no hospital deaths. The postoperative morbidity included two cases of pneumonia, one of atelectasis, and one of prolonged air leakage lasting more than 7 days. Wandering was postoperatively observed in two patients; one of these fell and fractured the left femur. At the time of our investigation, two patients were deceased, and the overall 5-year survival rate was 74.1 %. CONCLUSIONS: The postoperative morbidity and long-term results of schizophrenic patients with lung cancer were acceptable. Therefore, even in patients with schizophrenia, surgical treatment for lung cancer should be recommended when deemed to be necessary.

Medical teleconferencing with high-definition video presentation on the 'usual' Internet.

Although medical teleconferences on advanced academic networks have been common (Telemed J E Health 15:112-117, 1; Asian J Endosc Surg 3:185-188, 2; Surg Today 41:1579-1581, 3; Telemedicine development center of Asia. http://www.aqua.med.kyushu-u.ac.jp/eg/index.html . Accessed 6 March 2013, 4), reports regarding 'usual' Internet teleconferences or tele-lectures employing a telecommunication system for business use are very rare. Medical teleconferences and tele-lectures on the Internet were held three times between our institutions and other institutions, using the 'HD Com' made by Panasonic (HD Com. http://panasonic.biz/com/visual/ . Accessed 6 March 2013, 5), which is a high-definition telecommunication system for business tele-meeting. All of our medical telecommunications were successfully completed without any troubles. This system allows for all kinds of presentations using personal computers to be made from each station, so that discussions with high-definition surgical video presentation, which has recently been developed, could be effortlessly established despite the distance between institutions. Unlike telecommunication using advanced academic networks, this system can run without any need for specific engineering support, on the usual Internet. Medical telecommunication employing this system is likely to become common among ordinary hospitals in the near future.

Frequency of multiple primary cancers in the lung and other organs in hemodialysis patients.

OBJECTIVE: We examined whether cancers frequently occur in hemodialysis patients, and therefore, investigated the features and outcomes of hemodialysis patients who had undergone surgery for non-small cell lung cancer. METHODS: Between 1995 and 2011, 14 hemodialysis patients with lung cancer (8 males and 6 females) with a mean age of 67.0 years successfully underwent pulmonary resection at our institution. We investigated the 5-year survival rate and causes of death. The occurrence of multiple primary cancers in our patients and other lung-cancer patients reported in the articles were statistically compared by Chi-square test. A p value <0.05 was considered to be statistically significant. RESULTS: The 5-year survival rate was 47.3 %, and six patients had died before our investigation. Four of the six had died of non-cancerous diseases related to hemodialysis. Five of 14 patients had a history of other primary cancers in other organs, and this incidence rate of multiple primary cancers was significantly higher than in other lung-cancer patients (p = 0.0071). CONCLUSION: The frequency of cancer in hemodialysis patients can be underestimated because of their early deaths by non-cancerous diseases. However, the incidence rate of multiple primary cancers may represent a unique characteristic of such patients.

Off-the-job training for VATS employing anatomically correct lung models.

We evaluated our simulated major lung resection employing anatomically correct lung models as "off-the-job training" for video-assisted thoracic surgery trainees. A total of 76 surgeons voluntarily participated in our study. They performed video-assisted thoracic surgical lobectomy employing anatomically correct lung models, which are made of sponges so that vessels and bronchi can be cut using usual surgical techniques with typical forceps. After the simulation surgery, participants answered questionnaires on a visual analogue scale, in terms of their level of interest and the reality of our training method as off-the-job training for trainees. We considered that the closer a score was to 10, the more useful our method would be for training new surgeons. Regarding the appeal or level of interest in this simulation surgery, the mean score was 8.3 of 10, and regarding reality, it was 7.0. The participants could feel some of the real sensations of the surgery and seemed to be satisfied to perform the simulation lobectomy. Our training method is considered to be suitable as an appropriate type of surgical off-the-job training.

Medical teleconference about thoracic surgery using free Internet software.

Surgical teleconferences using advanced academic networks are becoming common; however, reports regarding Internet teleconferencing using free software packages such as Skype, USTREAM, and Dropbox are very rare. Teleconferences concerning mainly surgical techniques were held five times between Fukuoka University Hospital and other institutions from April to September 2010. These teleconferences used Skype and USTREAM as videophones to establish communication. Both PowerPoint presentations and surgical videos were made. These presentation files were previously sent to all stations via mail, e-mail, or Dropbox, and shared. A slide-show was simultaneously performed following the presenter's cue in each station. All teleconferences were successfully completed, even though there were minor instances of the Skype link being broken for unknown reasons during the telecommunication. Internet surgical teleconferences using ordinary software are therefore considered to be sufficiently feasible. This method will become more convenient and common as the Internet environments advance.

Does pneumothorax occurrence correlate with a change in the weather?

PURPOSE: There has been speculation that weather changes correlate with the incidence of spontaneous pneumothorax, although this has not been verified. Moreover, there are no significant data available on the meteoropathic pneumothorax in Asia. The aim of this study was to investigate the possible correlation and to compare our results to those of the United States and Europe. METHODS: From January 2000 to December 2009, 317 spontaneous pneumothorax cases with clear dates of onset were treated in our institution. Using the meteorological data of Fukuoka, Japan, the days with and without an occurrence of pneumothorax were statistically compared in terms of atmospheric pressure, the amount of precipitation, temperature, humidity, hours of sunshine, and occurrence of a typhoon and lightning. RESULTS: Multivariate analysis revealed that a decrease in the hours of sunshine, an increase in mean temperatures 2 days before the incidence, and the days following a day with lightning were all significantly correlated with the occurrence of pneumothorax (P = 0.2 days before the incidence, and the days following a day with lightning were all significantly correlated with the occurrence of pneumothorax (P = 0.0083, 0.0032, 0.0351, respectively). However, typhoons, as an "unusual" weather condition, did not influence the incidence of pneumothorax (P = 0.983). CONCLUSIONS: Our results show strong similarities with reports from European countries despite the different climates. We conclude that the occurrence of pneumothorax appears to correlate with some weather conditions in Japan.

Clinical outcome after pulmonary resection for lung cancer patients on hemodialysis.

BACKGROUND: The number of operations for patients with malignant tumors receiving long-term hemodialysis has been increasing; however, there are only few reports about pulmonary resection for the patients with lung cancer. METHODS: Between 1995 and 2009, 11 hemodialysis patients (6 men, 5 women; mean age, 66.4 years) with non-small cell lung cancer underwent pulmonary resection at our institution. We retrospectively evaluated their postoperative clinical outcomes and long-term results. RESULTS: The underlying kidney conditions included nephrosclerosis in 3, diabetic nephropathy in 3, glomerulonephritis in 1, and polycystic kidney in 1; 3 patients had undergone nephrectomy. The median duration of hemodialysis preoperatively was 5.0 years. Three patients had been treated for previous carcinoma. The histopathologic diagnoses were adenocarcinoma in 9 patients and squamous cell carcinoma in 2. Procedures included lobectomy in 9, pneumonectomy in 1, and wedge resection in 1. There were no in-hospital deaths. Postoperative morbidity included 2 cases of pneumonia and 1 of chylothorax. At the time of our investigation, 6 patients were dead; 2 of cancer and 4 of noncancer causes. The overall 5-year survival rate of 11 patients was 28.0%. CONCLUSIONS: Hemodialysis is not a contraindication to lung resection, despite the high morbidity rate. Surgical treatments, including lobectomy, remain one of effective treatments for patients on hemodialysis with lung cancer.