Noninvasive Ventilation Interfaces in the Treatment of Acute Respiratory Insufficiency: A Critical Review

Background: Noninvasive ventilation (NIV) is an important therapeutic modality for the treatment of acute respiratory failure (ARF). In this review, we critically analyze randomized controlled trials on the most used NIV interfaces in the treatments of ARF. Methods: The searches were conducted in the Medline, Lilacs, PubMed, Cochrane, and Pedro databases from June to November 2021. The inclusion criteria were Randomized clinical trials (RCTs) published from 2016 to 2021 in Portuguese, Spanish, or English and involving adults (aged ≥ 18 years). The eligibility criteria for article selection were based on the PICO strategy: Population—Adults with ARF;Intervention—NIV Therapy;Comparison—Conventional oxygen therapy, high-flow nasal cannula (HFNC) oxygen therapy, or NIV;Outcome—improvement in ARF. The search for articles and the implementation of the inclusion criteria were independently conducted by two researchers. Results: Seven scientific articles involving 574 adults with ARF due to various causes, such as chest trauma, decompensated heart failure, coronavirus disease 2019 (COVID-19), and postoperative period, among others, were included. The interfaces cited in the studies included an oronasal mask, nasal mask, full-face mask, and helmet. In addition, some favorable outcomes related to NIV were reported in the studies, such as a reduction in the rate of orotracheal intubation and shorter length of stay in the ICU. Conclusions: The most cited interfaces in the treatment of ARF were the oronasal mask and the helmet.

Early respiratory complications after liver transplantation

The poor clinical conditions associated with end-stage cirrhosis,pre-existing pulmonary abnormalities,and high comorbidity rates in patients with high Model for End-Stage Liver Disease scores are all well-recognized factors that increase the risk of pulmonary complications after orthotopic liver transplantation(OLT)surgery.Many intraoperative and postoperative events,such as fluid overload,massive transfusion of blood products,hemodynamic instability,unexpected coagulation abnormalities,renal dysfunction,and serious adverse effects of reperfusion syndrome,are other factors that predispose an individual to postoperative respiratory disorders.Despite advances in surgical techniques and anesthesiological management,the lung may still suffer throughout the perioperative period from various types of injury and ventilatory impairment,with different clinical outcomes.Pulmonary complications after OLT can be classified as infectious or non-infectious.Pleural effusion,atelectasis,pulmonary edema,respiratory distress syndrome,and pneumonia may contribute considerably to early morbidity and mortality in liver transplant patients.It is of paramount importance to accurately identify lung disorders because infectious pulmonary complications warrant speedy and aggressive treatment to prevent diffuse lung injury and the risk of evolution into multisystem organ failure.This review discusses the most common perioperative factors that predispose an individual to postoperative pulmonary complications and these complications’early clinical manifestations after OLT and influence on patient outcome.

Risk factors and prognosis of critically ill cancer patients with postoperative acute respiratory insufficiency

BACKGROUND:This study aimed to investigate the risk factors and outcome of critically ill cancer patients with postoperative acute respiratory insufficiency.METHODS:The data of 190 critically ill cancer patients with postoperative acute respiratory insufficiency were retrospectively reviewed.The data of 321 patients with no acute respiratory insufficiency as controls were also collected.Clinical variables of the first 24 hours after admission to intensive care unit were collected,including age,sex,comorbid disease,type of surgery,admission type,presence of shock,presence of acute kidney injury,presence of acute lung injury/acute respiratory distress syndrome,acute physiologic and chronic health evaluation(APACHE Ⅱ) score,sepsis-related organ failure assessment(SOFA),and PaO_2/FiO_2 ratio.Duration of mechanical ventilation,length of intensive care unit stay,intensive care unit death,length of hospitalization,hospital death and one-year survival were calculated.RESULTS:The incidence of acute respiratory insufficiency was 37.2%(190/321).Multivariate logistic analysis showed a history of chronic obstructive pulmonary diseases(P=0.001),surgeryrelated infection(P=0.004),hypo-volemic shock(P<0.001),and emergency surgery(P=0.018),were independent risk factors of postoperative acute respiratory insufficiency.Compared with the patients without acute respiratory insufficiency,the patients with acute respiratory insufficiency had a prolonged length of intensive care unit stay(P<0.001),a prolonged length of hospitalization(P=0.006),increased intensive care unit mortality(P=0.001),and hospital mortality(P<0.001).Septic shock was shown to be the only independent prognostic factor of intensive care unit death for the patients with acute respiratory insufficiency(P=0.029,RR:8.522,95%CI:1.243-58.437,B=2.143,SE=0.982,Wald=4.758).Compared with the patients without acute respiratory insufficiency,those with acute respiratory insufficiency had a shortened one-year survival rate(78.7%vs.97.1%,P<0.001).CONCLUSION:A history of chronic obstructive pulmonary diseases,surgery-related infection,hypovolemic shock and emergency surgery were risk factors of critically ill cancer patients with postoperative acute respiratory insufficiency.Septic shock was the only independent prognostic factor of intensive care unit death in patients with acute respiratory insufficiency.Compared with patients without acute respiratory insufficiency,those with acute respiratory insufficiency had adverse shortterm outcome and a decreased one-year survival rate.

Atypical respiratory complications of dengue fever

In last decade,dengue has emerged as one of the most important vector born disease.With increasing cases,uncommon presentations and complications are now commonly recognized.Here,we report two cases of rare pattern of respiratory involvement in dengue:acute respiratory distress syndrome and bronchiolitis with respiratory failure.

Innovative integration of lung ultrasound and wearable monitoring for predicting pulmonary complications in colorectal surgery:A prospective study

BACKGROUND Postoperative pulmonary complications(PPCs)are common in patients who undergo colorectal surgery.Studies have focused on how to accurately diagnose and reduce the incidence of PPCs.Lung ultrasound has been proven to be useful in preoperative monitoring and postoperative care after cardiopulmonary surgery.However,lung ultrasound has not been studied in abdominal surgeries and has not been used with wearable devices to evaluate the influence of postoperative ambulation on the incidence of PPCs.AIM To investigate the relationship between lung ultrasound scores,PPCs,and postoperative physical activity levels in patients who underwent colorectal surgery.METHODS In this prospective observational study conducted from November 1,2019 to August 1,2020,patients who underwent colorectal surgery underwent daily bedside ultrasonography from the day before surgery to postoperative day(POD)5.Lung ultrasound scores and PPCs were recorded and analyzed to investigate their relationship.Pedometer bracelets measured the daily movement distance for 5 days post-surgery,and the correlation between postoperative activity levels and lung ultrasound scores was examined.RESULTS Thirteen cases of PPCs was observed in the cohort of 101 patients.The mean(standard deviation)peak lung ultrasound score was 5.32(2.52).Patients with a lung ultrasound score of≥6 constituted the high-risk group.High-risk lung ultrasound scores were associated with an increased incidence of PPCs after colorectal surgery(logistic regression coefficient,1.715;odds ratio,5.556).Postoperative movement distance was negatively associated with the lung ultrasound scores[Spearman’s rank correlation coefficient(r),-0.356,P<0.05].CONCLUSION Lung ultrasound effectively evaluates pulmonary condition post-colorectal surgery.Early ambulation and respiratory exercises in the initial two PODs will reduce PPCs and optimize postoperative care in patients undergoing colorectal surgery.

Effect of sedation on short-term and long-term outcomes of critically ill patients with acute respiratory insufficiency

BACKGROUND: The present study aimed to determine the short-term and long-term outcomes of critically ill patients with acute respiratory insuffi ciency who had received sedation or no sedation.METHODS: The data of 91 patients who had received mechanical ventilation in the first 24 hours between November 2008 and October 2009 were retrospectively analyzed. These patients were divided into two groups: a sedation group(n=28) and a non-sedation group(n=63). The patients were also grouped in two groups: deep sedation group and daily interruption and /or light sedation group.RESULTS: Overall, the 91 patients who had received ventilation ≥48 hours were analyzed. Multivariate analysis demonstrated two independent risk factors for in-hospital death: sequential organ failure assessment score(P=0.019, RR 1.355, 95%CI 1.051–1.747, B=0.304, SE=0.130, Wald=50483) and sedation(P=0.041, RR 5.015, 95%CI 1.072–23.459, B=1.612, SE=0.787, Wald=4.195). Compared with the patients who had received no sedation, those who had received sedation had a longer duration of ventilation, a longer stay in intensive care unit and hospital, and an increased in-hospital mortality rate. The Kaplan-Meier method showed that patients who had received sedation had a lower 60-month survival rate than those who had received no sedation(76.7% vs. 88.9%, Log-rank test=3.630, P=0.057). Compared with the patients who had received deep sedation, those who had received daily interruption or light sedation showed a decreased in-hospital mortality rate(57.1% vs. 9.5%, P=0.008). The 60-month survival of the patients who had received deep sedation was signifi cantly lower than that of those who had daily interruption or light sedation(38.1% vs. 90.5%, Log-rank test=6.783, P=0.009).CONCLUSIONS: Sedation was associated with in-hospital death. The patients who had received sedation had a longer duration of ventilation, a longer stay in intensive care unit and in hospital, and an increased in-hospital mortality rate compared with the patients who did not receive sedation. Compared with daily interruption or light sedation, deep sedation increased the in-hospital mortality and decreased the 60-month survival for patients who had received sedation.

Effect of Right Supine Tracheal Extubation on Respiratory Complications and Airway Pressure in the Waking Period of General Anesthesia in Pediatric Stomatology

Objective: The purpose of this study was to investigate the effect of right supine endotracheal intubation on respiratory complications and airway pressure of general anesthesia, and to provide guidance for clinical application. Methods: Seventy-two children who received oral treatment under general anesthesia from November 2020 to November 2021 in Yantai Stomatological Hospital were randomly divided into three groups, 24 cases in each group. All three groups of children entered the PACU after the surgery. The children in Group I were extubated in the supine position, the children in Group II were immediately changed to the right decubitus after extubation in the horizontal position, and the children in Group III were extubated in the right decubitus. HR, MAP and SpO2 of T1 (the time point at the beginning of surgery), T2 (the time point at 1 hour after surgery), T3 (the time point after extubation), T4 (the time point at 1 minute after extubation), T5 (the time point at 3 minutes after extubation) in the three groups were observed, t1 (operation time) and t2 (the time of leaving the PACU) were recorded. The airway pressure (P1) in the recumbent position and the airway pressure (P2) in the right decubitus position before extubation were recorded in Group III. The number of sputum suction and complications after extubation were counted. Results: The t2 in Group III was shorter than that in Groups I and II, and the number of sputum suction in Group III was less than that in Groups I and II (P < 0.05). The HR at T3, T4 and T5 in Group III was lower than that in Group I, and the HR at T4 and T5 was lower than that in Group II (P < 0.05). There were significant differences in the incidence of respiratory complications among the three groups (P < 0.05). The incidence of asphyxia, bucking and glossocoma postoperative agitation in Group III was significantly lower than that in Group I, and the incidence of asphyxia and choking was lower than that in Group II (P < 0.05). The incidence of glossoptosis in Group II was significantly lower than that in Group I (P < 0.05). In Group III, the airway pressure P2 in the right decubitus position during endotracheal intubation was higher than that of P1 in the supine position during endotracheal intubation (P < 0.05). The 95% Confidence Interval (CI) of airway pressure difference was 1.416 - 1.834 cmH2O. Conclusion: For children undergoing intraoral therapy under general anesthesia, tracheal extubation in the right decubitus position can improve the circulation fluctuation before and after extubation, reducing the number of sputum suction and respiratory tract-related complications, and can shorten the departure time. The body position change during the tracheal intubation will slightly increase the airway pressure, but the supine position after extubation can better ensure the smooth spontaneous breathing of children, which can provide the reference for clinical application.

CT Manifestations of Lung Changes and Complications in Patients with Severe Acute Respiratory Syndrome

Objective:To investigate the rol e of CT scanning in diagnosing severe acute respiratory syndrome(SARS). Methods: One hundred and twelve times of spiral CT scanning, 106 t imes on the chest with standard pulmonary and mediastinal window, 5 on the brain and once on the abdomen, were performed in 82 patients (37 males and 45 females ) of SARS. Results: Bilateral shadows showed in 66 patients (80.48%) and unil ateral shadow in 16 (19.52%). The lung CT findings were sub pleural focal con solidation in 26 patients (31.70%), flaky cloudy opacity in 53 (64.63%), large a rea consolidation in 9 (10.97%), ground glass blurry shadow in 31 (37.80%), a lveolar substantive shadow in 14 (17.07%) and interstitial changes in 16 (19.51% ). The pulmonary CT signs of SARS were relatively characterized by: (1) The lesi ons tending to multiply occur, mostly to be bilaterally distributed and commonly involved in the lower lung field. (2) The lung shadows mostly showed as sub pleural focal consolidation, flaky cloudy shadow, large area consolidation, grou nd glass blurry shadow, and often accompanied with signs of broncho inflat ion. (3) Having opacified nodular shadows in the alveolar cavities. (4) Rapid pr ogressions or changes on the size, amount, and distribution of the lesions likel y to be found in dynamic observation of chest X ray and CT scanning, i.e., ma rkedly dynamic changes found within 24 to 48 hrs. Lesions with these characteris tics may be recognized as pulmonary changes possibly induced by SARS. Complicati ons were found in 6 patients (7.31%), including tuberculosis of lung and brain a ccompanied with pneumomediastinum in one patient, secondary infection of lung in 2, pneumothorax in 1, pulmonary fungus in 1, and pyothorax in 1.Conclusion: CT scanning is a sensitive method for diagnosis of SAR S, by which more accurate assessment of the abnormal changes of lung and occurre nce of complications in SARS patients can be made.

Does Obstructive Sleep Apnea (OSA) Increase the Risk of Post-Operative Respiratory Complications after Bariatric Surgery?

Background: OSA affects up to quarter of general population. It is associated with morbid obesity with a higher morbidity and mortality rates. STOP Bang questionnaire is a validated method for OSA screening. OSA patients are at high risk of developing airway obstruction, cardiac events, congestive heart failure, stroke and desaturation post operatively. The aim of this study is to evaluate adverse respiratory events in patients undergoing bariatric surgery in relation to risk of OSA using Stop Bang questionnaire. Methods: This prospective double cohort study was conducted in Tanta University Hospital from Marchto August 2017. During the preoperative assessment, STOP-BANG questionnaire was performed. After extubation, patients were transferred to PACU unit. Respiratory complications were assessed thereafter. Based on STOP-BANG score, patients were divided into two groups, high risk of OSA with STOP-BANG > 3 (Group I) and low risk of OSA with STOP-BANG Results: 104 patients were included in this study. Group I had more comorbidities in the form of CAD (15% versus 2%, P 0.001). Higher number of respiratory complications was noted in high-risk group (31 patients, 59%) compared to (24 patients, 46%) in group II yet, it was not significant. Conclusion: Obese patients with STOP-BANG score > 3 undergoing bariatric surgery are associated with hypertension, dyslipidemia, CAD, and renal insufficiency. High-risk OSA obese patients are at higher risk of developing respiratory compilations like inability to breathe deeply and hypoxia in postoperatively.

Recent Progress in the Study of Respiratory Complications Correlated with TACE for HCC

Due to the insidious clinical symptoms of early hepatocellular carcinoma (HCC), most of the patients diagnosed at intermediate-to-advanced stage HCC, and they lost the opportunity for curative treatment. Comprehensive interventional therapy plays an important role in prolonging the median survival of patients with intermediate-to-advanced stage HCC, among which transcatheter hepatic artery chemoembolization (TACE) is the most commonly used minimally invasive treatment. However, TACE may cause many postoperative complications such as liver function damage, biliary tract injury, upper gastrointestinal bleeding. Among them, TACE-related respiratory complications have been reported in a few articles, which are extremely rare but serious, and there are still many uncertainties about their occurrence mechanisms and risk factors. This article is aim to focus on the research progress of the respiratory complications of TACE, thus making progress on TACE-treatment aftercare.

Analysis of the impact of ERAS-based respiratory function training on older patients’ability to prevent pulmonary complications after abdominal surgery

BACKGROUND In China,as the population grows older,the number of elderly people who have died from respiratory problems has increased.AIM To investigate whether enhanced recovery after surgery(ERAS)-based respiratory function training may help older patients who had abdominal surgery suffer fewer pulmonary problems,shorter hospital stays,and improved lung function.METHODS The data of 231 elderly individuals having abdominal surgery was retrospectively analyzed.Based on whether ERAS-based respiratory function training was provided,patients were divided into ERAS group(n=112)and control group(n=119).Deep vein thrombosis(DVT),pulmonary embolism(PE),and respiratory tract infection(RTI)were the primary outcome variables.Secondary outcome variables included the Borg score Scale,FEV1/FVC and postoperative hospital stay.RESULTS The percentage of 18.75%of ERAS group participants and 34.45%of control group participants,respectively,had respiratory infections(P=0.007).None of the individuals experienced PE or DVT.The ERAS group’s median postoperative hospital stay was 9.5 d(3-21 d)whereas the control groups was 11 d(4-18 d)(P=0.028).The Borg score decreased on the 4th d following surgery in the ERAS group compared to the 2nd d prior(P=0.003).The incidence of RTIs was greater in the control group than in the ERAS group among patients who spent more than 2 d in the hospital before surgery(P=0.029).CONCLUSION ERAS-based respiratory function training may reduce the risk of pulmonary complications in older individuals undergoing abdominal surgery.

Respiratory Complications of Measles in the Pediatric Ward of the Regional Hospital of Kindia/Guinea

Introduction: Measles is a highly contagious infectious disease caused by the measles virus belonging to the morbillivirus genus, the measles morbillivirus species and the Paramyxoviridae families. The aim was to study respiratory complications due to measles in children aged 1 to 15 in the pediatric ward of the Kindia regional hospital. Materials and Methods: A transversal descriptive study was carried out in the pediatrics department of the Kindia Regional Hospital from October 1, 2019, to March 31, 2020, on children aged 1 to 15 years hospitalized for measles with respiratory complications. Results: 53 cases of measles were recorded, i.e. 11.71% of hospital pathologies including 32 cases of respiratory complications, i.e. 60.38% with an M/F sex ratio of 1.66, male predominance of 62.5%, and a mean age of 4.10 ± 2.8 years. The outcome was favorable in 90.62% of our patients. The mortality was 9.38% with an average hospital stay of 6.8 ± 3.04 days. Conclusion: The respiratory complication of measles is a serious pathology due to the risk of mortality that it can cause, a consultation followed by rapid treatment can contribute to a reduction in complications and a faster cure.

Strategies to reduce pulmonary complications after esophagectomy

Esophagectomy,the surgical removal of all or part of the esophagus,is a surgical procedure that is associated with high morbidity and mortality.Pulmonary complications are an especially important postoperative problem.Therefore,many perioperative strategies to prevent pulmonary complications after esophagectomy have been investigated and introduced in daily clinical practice.Here,we review these strategies,including improvement of patient performance and technical advances such as minimally invasive surgery that have been implemented in recent years.Furthermore,interventions such as methylprednisolone,neutrophil elastase inhibitor and epidural analgesia,which have been shown to reduce pulmonary complications,are discussed.Benefits of the commonly applied routine nasogastric decompression,delay of oral intake and prophylactic mechanical ventilation are unclear,and many of these strategies are also evaluated here.Finally,we will discuss recent insights and new developments aimed to improve pulmonary outcomes after esophagectomy.

Acute complications of spinal cord injuries

The aim of this paper is to give an overview of acute complications of spinal cord injury(SCI). Along with motor and sensory deficits, instabilities of the cardiovascular, thermoregulatory and broncho-pulmonary system are common after a SCI. Disturbances of the urinary and gastrointestinal systems are typical as well as sexual dysfunction. Frequent complications of cervical and high thoracic SCI are neurogenic shock, bradyarrhythmias, hypotension, ectopic beats, abnormal temperaturecontrol and disturbance of sweating, vasodilatation and autonomic dysreflexia. Autonomic dysreflexia is an abrupt, uncontrolled sympathetic response, elicited by stimuli below the level of injury. The symptoms may be mild like skin rash or slight headache, but can cause severe hypertension, cerebral haemorrhage and death. All personnel caring for the patient should be able to recognize the symptoms and be able to intervene promptly. Disturbance of respiratory function are frequent in tetraplegia and a primary cause of both short and long-term morbidity and mortality is pulmonary complications. Due to physical inactivity and altered haemostasis, patients with SCI have a higher risk of venous thromboembolism and pressure ulcers. Spasticity and pain are frequent complications which need to be addressed. The psychological stress associated with SCI may lead to anxiety and depression. Knowledge of possible complications during the acute phase is important because they may be life threatening and/ or may lead to prolonged rehabilitation.

Pathophysiology of pulmonary complications of acute pancreatitis

Acute pancreatitis in its severe form is complicated by multiple organ system dysfunction, most importantly by pulmonary complications which include hypoxia, acute respiratory distress syndrome, atelectasis, and pleural effusion. The pathogenesis of some of the above complications is attributed to the production of noxious cytokines. Clinically significant is the early onset of pleural effusion, which heralds a poor outcome of acute pancreatitis. The role of circulating trypsin, phospholipase A2, platelet activating factor, release of free fatty acids, chemoattractants such as tumor necrsosis factor （TNF）- alpha, interleukin （IL）-1, IL-6, IL-8, fMet-leu-phe （a bacterial wall product）, nitric oxide, substance P, and macrophage inhlbitor factor is currently studied. The hope is that future management of acute pancreatitis with a better understanding of the pathogenesis of lung injury will be directed against the production of noxious cytokines.

Pulmonary complications of transcatheter arterial chemoembolization for hepatocellular carcinoma

Transcatheter arterial chemoembolization(TACE) is an effective palliative intervention that is widely accepted for the management of hepatocellular carcinoma(HCC). Post-TACE pulmonary complications resulting in acute lung injury(ALI) or acute respiratory distress syndrome(ARDS) are rare events. Pulmonary complications after TACE are thought to be related to chemical injury subsequent to the migration of the infused ethiodized oil or chemotherapeutic agent to the lung vasculature, facilitated by arteriovenous(AV) shunts within the hyper-vascular HCC. We review herein the literature on pulmonary complications related to TACE for HCC. Post-TACE pulmonary complications have included pulmonary oil embolism, interstitial pneumonitis, chemical pneumonitis, ALI, ARDS, lipoid pneumonia, acute eosinophilic and neutrophilic pneumonia, bilious pleuritis, pulmonary abscess, pulmonary tumor embolism, and possibly pulmonary metastasis with HCC. The risk factors associated with post-TACE pulmonary complications identified in the literature include large hyper-vascular HCC with AV shunts, large-volume Lipiodol infusion, and embolization via the right inferior phrenic artery. However, the absence of known risk factors is not a guarantee against serious complications. An astute awareness of the potential post-TACE pulmonary complications should expedite appropriate therapeutic interventions and increase potential for early recovery.

Surgical complications in COVID-19 patients in the setting of moderate to severe disease

The coronavirus disease 2019(COVID-19)pandemic has had a considerable impact on the work of physicians and surgeons.The connection between the patient and the surgeon cannot be replaced by telemedicine.For example,the surgical staff faces more serious difficulties compared to non-surgical specialists during the COVID-19 pandemic.The primary concerns include the safest solutions for protecting healthcare staff and patients and the ability to provide adequate surgical care.Additionally,the adverse effects of any surgery delays and the financial consequences complicate the picture.Therefore,patients’admission during the COVID-19 pandemic should be taken into consideration,as well as preoperative measures.The COVID-19 situation brings particular risk to patients during surgery,where preoperative morbidity and mortality rise in either asymptomatic or symptomatic COVID-19 patients.This review discusses the recent factors associated with surgical complications,mortality rates,outcomes,and experience in COVID-19 surgical patients.

Respiratory failure in the hematopoietic stem cell transplant recipient

The number of patients receiving hematopoietic stem cell transplantation(HSCT) is rapidly rising worldwide. Despite substantial improvements in peri-transplant care, pulmonary complications resulting in respiratory failure remain a major contributor to morbidity and mortality in the post-transplant period, and represent a major barrier to the overall success of HSCT. Infectious complications include pneumonia due to bacteria, viruses, and fungi, and most commonly occur during neutropenia in the early post-transplant period. Non-infectious complications include idiopathic pneumonia syndrome, periengraftment respiratory distress syndrome, diffuse alveolar hemorrhage, pulmonary veno-occlusive disease, delayed pulmonary toxicity syndrome, cryptogenic organizing pneumonia, bronchiolitis obliterans syndrome, and post-transplant lymphoproliferative disorder. These complications have distinct clinical features and risk factors, occur at differing times following transplant, and contribute to morbidity and mortality.

Surgical resection of a giant thymolipoma causing respiratory failure: A case report

BACKGROUND Thymolipoma is a rare benign tumor arising from the anterior mediastinal thymus and is composed of mature fatty tissue and interspersed nonneoplastic thymic tissue. This tumor accounts for only a small percentage of mediastinal masses, and the majority of them are asymptomatic and found incidentally. To date, fewer than 200 cases have been published in the world literature, of which most excised tumors weighed less than 0.5 kg and the largest weighed 6 kg.CASE SUMMARY A 23-year-old man presented with a complaint of progressive breathlessness for 6mo. His forced vital capacity was only 23.6% of the predicted capacity, and his arterial partial pressure of oxygen and carbon dioxide were 51 and 60 mmHg,respectively, without oxygen inhalation. Chest computed tomography revealed a large fat-containing mass in the anterior mediastinum that measured 26 cm × 20cm × 30 cm in size and occupied most of the thoracic cavity. Percutaneous mass biopsy revealed only thymic tissue without signs of malignancy. A right posterolateral thoracotomy was successfully performed to remove the tumor along with the capsule, and the excised tumor weighed 7.5 kg, which to our knowledge, was the largest surgically removed tumor of thymic origin. Postoperatively, the patient’s shortness of breath was resolved, and the histopathological diagnosis was thymolipoma. No signs of recurrence were observed at the 6-mo follow-up.CONCLUSION Giant thymolipoma causing respiratory failure is rare and dangerous. Despite the high risks, surgical resection is feasible and effective.

Extracorporeal membrane oxygenation for coronavirus disease 2019-associated acute respiratory distress syndrome:Report of two cases and review of the literature

BACKGROUND Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus-2,is a worldwide pandemic.Some COVID-19 patients develop severe acute respiratory distress syndrome and progress to respiratory failure.In such cases,extracorporeal membrane oxygenation(ECMO)treatment is a necessary life-saving procedure.CASE SUMMARY Two special COVID-19 cases—one full-term pregnant woman and one elderly(72-year-old)man—were treated by veno-venous(VV)-ECMO in the Second People’s Hospital of Zhongshan,Zhongshan City,Guangdong Province,China.Both patients had developed refractory hypoxemia shortly after hospital admission,despite conventional support,and were therefore managed by VV-ECMO.Although both experienced multiple ECMO-related complications on top of the COVID-19 disease,their conditions improved gradually.Both patients were weaned successfully from the ECMO therapy.At the time of writing of this report,the woman has recovered completely and been discharged from hospital to home;the man remains on mechanical ventilation,due to respiratory muscle weakness and suspected lung fibrosis.As ECMO itself is associated with various complications,it is very important to understand and treat these complications to achieve optimal outcome.CONCLUSION VV-ECMO can provide sufficient gas exchange for COVID-19 patients with acute respiratory distress syndrome.However,it is crucial to understand and treat ECMO-related complications.