[Analysis of Influencing Factors of Complications for CT-guided 
Percutaneous Lung Biopsy].

BACKGROUND: Computed tomography guided percutaneous lung biopsy (CT-PLB) is a widely used method for the diagnosis of lung lesions. However, it is invasive, and the most common complications are pneumothorax and pulmonary hemorrhage, which can be life-threatening in severe cases. Therefore, the aim of this study is to analyze the independent risk factors affecting the occurrence of different complications of CT-PLB, so as to reduce the incidence of complications. METHODS: The 605 patients with complete clinical data who underwent CT-PLB in our hospital from May 2018 to December 2019 were retrospectively analyzed. According to the location of the lesions, they were divided into subpleural group and non-subpleural group. The patients were divided into pneumothorax group, pulmonary hemorrhage group, pneumothorax with pulmonary hemorrhage group and non-pneumothorax/pulmonary hemorrhage group according to the complications. The risk factors affecting the incidence of different complications and the independent risk factors of each complication were analyzed. RESULTS: The incidence of pneumothorax was 34.1%, the incidence of pulmonary hemorrhage was 28.1%, and the incidence of pneumothorax complicated with pulmonary hemorrhage was 10.8% (63 cases). The independent risk factor affecting the incidence of subpleural pneumothorax was lesion size (P=0.002). The independent risk factors affecting the occurrence of pneumothorax in the non-subpleural group were plain scan CT value (P=0.035), length of needle through lung tissue (P=0.003), and thickness of needle through chest wall (P=0.020). Independent risk factors affecting the occurrence of pulmonary hemorrhage in the non-subpleural group were length of needle through lung tissue (P<0.001), △CT value of needle travel area (P=0.001), lesion size (P=0.034) and body position (P=0.014). The independent risk factors affecting the co-occurrence of pneumothorax and pulmonary hemorrhage were the length of needle through lung tissue (P<0.001) and the △CT value of needle travel area (P<0.001). CONCLUSIONS: CT-PLB is a safe and effective diagnostic method, which of high diagnostic value for lung lesions. Selecting the appropriate puncture program can reduce complications such as pneumothorax and pulmonary hemorrhage, and improve diagnosis and treatment efficiency.

Inhaled bronchodilators for the prevention and treatment of chronic lung disease in preterm infants.

BACKGROUND: Chronic lung disease (CLD) occurs frequently in preterm infants and is associated with respiratory morbidity. Bronchodilators have the potential effect of dilating small airways with muscle hypertrophy. Increased compliance and tidal volume, and decreased airway resistance, have been documented with the use of bronchodilators in infants with CLD. Therefore, bronchodilators are widely considered to have a role in the prevention and treatment of CLD, but there remains uncertainty as to whether they improve clinical outcomes. This is an update of the 2016 Cochrane review. OBJECTIVES: To determine the effect of inhaled bronchodilators given as prophylaxis or as treatment for chronic lung disease (CLD) on mortality and other complications of preterm birth in infants at risk for or identified as having CLD. SEARCH METHODS: An Information Specialist searched CENTRAL, MEDLINE, Embase, CINAHL and three trials registers from 2016 to May 2023. In addition, the review authors undertook reference checking, citation searching and contact with trial authors to identify additional studies. SELECTION CRITERIA: We included randomised and quasi-randomised controlled trials involving preterm infants less than 32 weeks old that compared bronchodilators to no intervention or placebo. CLD was defined as oxygen dependency at 28 days of life or at 36 weeks' postmenstrual age. Initiation of bronchodilator therapy for the prevention of CLD had to occur within two weeks of birth. Treatment of infants with CLD had to be initiated before discharge from the neonatal unit. The intervention had to include administration of a bronchodilator by nebulisation or metered dose inhaler. The comparator was no intervention or placebo. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane. Critical outcomes included: mortality within the trial period; CLD (defined as oxygen dependency at 28 days of life or at 36 weeks' postmenstrual age); adverse effects of bronchodilators, including hypokalaemia (low potassium levels in the blood), tachycardia, cardiac arrhythmia, tremor, hypertension and hyperglycaemia (high blood sugar); and pneumothorax. We used the GRADE approach to assess the certainty of the evidence for each outcome. MAIN RESULTS: We included two randomised controlled trials in this review update. Only one trial provided useable outcome data. This trial was conducted in six neonatal intensive care units in France and Portugal, and involved 173 participants with a gestational age of less than 31 weeks. The infants in the intervention group received salbutamol for the prevention of CLD. The evidence suggests that salbutamol may result in little to no difference in mortality (risk ratio (RR) 1.08, 95% confidence interval (CI) 0.50 to 2.31; risk difference (RD) 0.01, 95% CI -0.09 to 0.11; low-certainty evidence) or CLD at 28 days (RR 1.03, 95% CI 0.78 to 1.37; RD 0.02, 95% CI -0.13 to 0.17; low-certainty evidence), when compared to placebo. The evidence is very uncertain about the effect of salbutamol on pneumothorax. The one trial with usable data reported that there were no relevant differences between groups, without providing the number of events (very low-certainty evidence). Investigators in this study did not report if side effects occurred. We found no eligible trials that evaluated the use of bronchodilator therapy for the treatment of infants with CLD. We identified no ongoing studies. AUTHORS' CONCLUSIONS: Low-certainty evidence from one trial showed that inhaled bronchodilator prophylaxis may result in little or no difference in the incidence of mortality or CLD in preterm infants, when compared to placebo. The evidence is very uncertain about the effect of salbutamol on pneumothorax, and neither included study reported on the incidence of serious adverse effects. We identified no trials that studied the use of bronchodilator therapy for the treatment of CLD. Additional clinical trials are necessary to assess the role of bronchodilator agents in the prophylaxis or treatment of CLD. Researchers studying the effects of inhaled bronchodilators in preterm infants should include relevant clinical outcomes in addition to pulmonary mechanical outcomes.

Establishment of stellate ganglion block in mice.

BACKGROUND: There have been no reports on the successful implementation of stellate ganglion block (SGB) in mice. OBJECTIVES: This study aims to investigate a new method for implementing SGB in mice by placing them in a supine position with abducted upper limbs and touching the trachea and sternoclavicular joint with the hand. METHODS: Fifty BABL/C mice, 8-10 weeks, were selected and randomly divided into four groups: control group (n = 5); SGB-R group (n = 15); SGB-L group (n = 15); and SGB-L + R (group n = 15). SGB was administered with 0.15% ropivacaine solution in a volume of 0.1 mL. The control group received equal volumes of saline. Horner's syndrome, heart rate, and complications such as brachial plexus block, vascular injury, pneumothorax, local anesthetic toxicity, and death were observed. RESULTS: Horner's syndrome developed in 100% of SGB surviving mice; no difference was seen in the time to onset (100.4 ± 13.4 vs 96.7 ± 12.4, mean ± SD, seconds) and duration (264.1 ± 40.5 vs 296.3 ± 48.0, mean ± SD, min) of Horner's syndrome in the left and right SGB (P > 0.05). Compared with the control group (722 [708-726], median [IQR], bpm), the heart rate was significantly slowed down in the right SGB (475 [451.5-491], median [IQR], bpm) (P < 0.05). While the heart rate was slowed down after performing the left SGB, the difference was not statistically significant (P > 0.05). The overall complication rate was 18.4%, with a brachial plexus block rate of 12.3%, a vascular injury rate of 4.6%, and a mortality rate of 1.5%, as well as no local anesthetic toxicity (includes bilateral implementation of SGB) or pneumothorax manifestations were found. CONCLUSIONS: This method allows for the successful implementation of SGB in a mouse model.

Comparison of laser guidance and freehand hook-wire for CT-guided preoperative localization of pulmonary nodules.

PURPOSE: In VATS surgery, precise preoperative localization is particularly crucial when dealing with small-diameter pulmonary nodules located deep within the lung parenchyma. The purpose of this study was to compare the efficacy and safety of laser guidance and freehand hook-wire for CT-guided preoperative localization of pulmonary nodules. METHODS: This retrospective study was conducted on 164 patients who received either laser guidance or freehand hook-wire localization prior to Uni-port VATS from September 1st, 2022 to September 30th, 2023 at The First Affiliated Hospital of Soochow University. Patients were divided into laser guidance group and freehand group based on which technology was used. Preoperative localization data from all patients were compiled. The localization success and complication rates associated with the two groups were compared. The risk factors for common complications were analyzed. RESULTS: The average time of the localization duration in the laser guidance group was shorter than the freehand group (p<0.001), and the average CT scan times in the laser guidance group was less than that in the freehand group (p<0.001). The hook-wire was closer to the nodule in the laser guidance group (p<0.001). After the localization of pulmonary nodules, a CT scan showed 14 cases of minor pneumothorax (22.58%) in the laser guidance group and 21 cases (20.59%) in the freehand group, indicating no statistical difference between the two groups (p=0.763). CT scans in the laser guidance group showed pulmonary minor hemorrhage in 8 cases (12.90%) and 6 cases (5.88%) in the freehand group, indicating no statistically significant difference between the two groups (p=0.119). Three patients (4.84%) in the laser guidance group and six patients (5.88%) in the freehand group had hook-wire dislodgement, showing no statistical difference between the two groups (p=0.776). CONCLUSION: The laser guidance localization method possessed a greater precision and less localization duration and CT scan times compared to the freehand method. However, laser guidance group and freehand group do not differ in the appearance of complications such as pulmonary hemorrhage, pneumothorax and hook-wire dislodgement.

Pneumothorax, pneumomediastinum and subcutaneous emphysema as respiratory complications of COVID-19.

BACKGROUND: Pneumothorax, pneumomediastinum and subcutaneous emphysema are respiratory complications of Coronavirus disease 2019 occurring with noteworthy frequency in patients especially with severe disease. They can be life-threatening and often complicate patient managment. METHODS: This was a retrospective, observational study of patients admitted in Nepal Armed Police Force hospital from 13/05/2020 to 28/12/2021 diagnosed with pneumothorax, pneumomediastinum or subcutaneous emphysema singly or in combination. Data were collected from clinical charts, imaging records and electronic medical records of Severe Acute Respiratory Syndrome Coronavirus-type 2 positive patients 18 years and older. The frequency and type of the defined complications, the inflammatory markers and ventilatory parameters just prior to their diagnosis, the duration of hospitalization and ICU admission and in-hospital mortality rate were studied. RESULTS: Out of 4013 COVID-19 patients admitted in the hospital during the period, a total of 28 patients were observed to develop the complications, the overall incidence being 0.7% among hospitalized patients and 5.6% among ICU patients. The proportion of subcutaneous emphysema (64.3%) was highest followed by pneumomediastinum (46.4%) and then pneumothorax (39.3%) existing singly or in combination among the 28 patients, where four patients developed the complications spontaneously. Mean Positive End Expiratory Pressure of 12.1±2.6 cmH2O and Peak Inspiratory Pressure or Pressure Support of 30.9±10.3 cmH2O were observed for patients under positive pressure ventilation. Most of the patients who developed the complications (78.6%) died during treatment. CONCLUSIONS: Pulmonary air leak complications occur frequently in COVID-19 patients treated with or without positive pressure ventilation signifying increased disease severity, risk of ICU admission and high mortality rate. Hence, clinicians should be vigilant of these complications in all patients affected with COVID-19 and institute timely management.

Medical and surgical management of pneumothorax in diving and hyperbaric chambers.

The presence of a pneumothorax within a pressurized chamber represents unique diagnostic and management challenges. This is particularly the case in the medical and geographic remoteness of many chamber locations. Upon commencing chamber decompression, unvented intrapleural air expands. If its initial volume and/or degree of chamber pressure reduction is significant enough, a tension pneumothorax will result. Numerous reports chronicle failure to diagnose and manage in-chamber pneumothorax with resultant morbidity and one fatal outcome. Such cases have occurred in both medically remote and clinically based settings. This paper reviews pneumothorax and tension pneumothorax risk factors and clinical characteristics. It suggests primary medical management using the principle of oxygen-induced inherent unsaturation in concert with titrated chamber decompression designed to prevent intrapleural air expanding faster than it contracts. Should this conservative approach prove unsuccessful, and surgical venting becomes necessary or otherwise immediately indicated, interventional options are reviewed.

Pneumothorax during manned chamber operations: A summary of reported cases.

In-chamber pneumothorax has complicated medically remote professional diving operations, submarine escape training, management of decompression illness, and hospital-based provision of hyperbaric oxygen therapy. Attempts to avoid thoracotomy by combination of high oxygen partial pressure breathing (the concept of inherent unsaturation) and greatly slowed rates of chamber decompression proved successful on several occasions. When this delicate balance designed to prevent the intrapleural gas volume from expanding faster than it contracts proved futile, chest drains were inserted. The presence of pneumothorax was misdiagnosed or missed altogether with disturbing frequency, resulting in wide-ranging clinical consequences. One patient succumbed before the chamber had been fully decompressed. Another was able to ambulate unaided from the chamber before being diagnosed and managed conventionally. In between these two extremes, patients experienced varying degrees of clinical compromise, from respiratory distress to cardiopulmonary arrest, with successful resuscitation. Pneumothorax associated with manned chamber operations is commonly considered to develop while the patient is under pressure and manifests during ascent. However, published reports suggest that many were pre-existing prior to chamber entry. Risk factors included pulmonary barotrauma-induced cerebral arterial gas embolism, cardiopulmonary resuscitation, and medical or surgical procedures usually involving the lung. This latter category is of heightened importance to hyperbaric operations as an iatrogenically induced pneumothorax may take as long as 24 hours to be detected, perhaps long after a patient has been cleared for chamber exposure.

An 88-Year-Old Woman With Pneumothorax and Black Pleural Effusion.

CASE PRESENTATION: An 88-year-old woman was admitted to our hospital with the sudden onset of dyspnea after eating. The patient had undergone nephrectomy for a left renal tumor 24 years previously. The patient had been prescribed ferrous citrate for iron-deficiency anemia. She complained of appetite loss a few days before admission but had no abdominal pain. CT scan showed no abnormalities in the lungs but a mass in the liver.

Prospective Observation Study for Primary Spontaneous Pneumothorax: Incidence of and Risk Factors for Postoperative Neogenesis of Bullae.

PURPOSE: Details of the neogenesis of bullae (NOB), which causes recurrent primary spontaneous pneumothorax (PSP) following bullectomy, have not been reported and risk factors for NOB remain unclear. We aimed to clarify the details of NOB. METHODS: We conducted a prospective study using three computed tomography (CT) examinations performed 6, 12, and 24 months after bullectomy to identify the incidence of and risk factors for NOB. We enrolled 50 patients who underwent bullectomy for PSP. RESULTS: After excluding 11 patients who canceled the postoperative CT examination at 6 months after bullectomy, only 39 patients were analyzed. The incidence of NOB at 6, 12, and 24 months after bullectomy was 38.5%, 55.2%, and 71.2%, respectively. The rate of NOB in the operated lung was almost 2 times higher than that in the contralateral nonoperative lung. Male sex, multiple bullae on preoperative CT, long stapling line (≥7 cm), deep stapling depth (≥1.5 cm), and heavier resected sample (≥5 g) were suggested to be risk factors for NOB. CONCLUSIONS: We recognized a high incidence of postoperative NOB in PSP patients. Bullectomy itself seems to promote NOB. Postoperative NOB occurs frequently, especially in patients who require a large-volume lung resection with a long staple line.

The sensitivity of a neck CT scan in detecting pneumothoraces in nonpenetrating trauma.

BACKGROUND: The trauma-related pneumothorax is a common intrathoracic injury and can go undetected with detrimental outcomes. Chest computed tomography (CT) investigation in low- to middle-income countries (LMIC) is not always readily available during emergency situations and increased workloads. However, alternative investigations all have limitations in including pneumothoraces. Patients may have trauma indications for CT of the head and neck. The neck CT scan may hold an extra potential advantage in pneumothorax detection. This study aimed to assess its sensitivity in pneumothorax detection in nonpenetrating trauma. METHODS: A retrospective study was conducted from 1 January 2016 to 31 December 2021. All adult patients sustaining nonpenetrating injuries, and investigated with chest and neck CT scans were included. The chest CT scan was the gold standard against,which the neck CT scan was compared to determine the accuracy of pneumothorax detection. Stata version 16 was used for descriptive statistical analysis, and a p-value of 0.05 was considered statistically significant. RESULTS: One thousand ninety three were eligible for evaluation; 204 (18.66%) pneumothoraces were detected on chest CT scans, 200 (98.0%) of which were also detected on the neck CT scan, producing a sensitivity of 98.0% (95% CI 95.1-99.5%) and a specificity of 100% (95% CI 99.6-100%). Most pneumothoraces were detected at T1 level (45.09%), followed by T2 (43.62%). CONCLUSION: The neck CT scan has demonstrated high sensitivity and specificity in pneumothorax detection. Thus, it may be used as an additional tool for those who could not receive or do not need a formal chest CT but have an indication for neck CT scans.

Endobronchial valves for emphysema and persistent air-leak: 10-year experience in an Asian country.

BACKGROUND: Endobronchial valve (EBV) therapy, a validated method for bronchoscopic lung volume reduction (BLVR) in severe emphysema, has been explored for persistent air-leak (PAL) management. However, its effectiveness and safety in the Asian population require further real-world evaluation. In this study, we assessed the outcomes of treatment with EBV within this demographic. METHODS: We conducted a retrospective analysis of medical records from 11 Korean centers. For the emphysema cohort, inclusion criteria were patients diagnosed with emphysema who underwent bronchoscopy intended for BLVR. We assessed these patients for clinical outcomes of chronic obstructive pulmonary disease. All patients with PAL who underwent treatment with EBV were included. We identified the underlying causes of PAL and evaluated clinical outcomes after the procedure. RESULTS: The severe emphysema cohort comprised 192 patients with an average age of 70.3 years, and 95.8% of them were men. Ultimately, 137 underwent treatment with EBV. Three months after the procedure, the BLVR group demonstrated a significant improvement in forced expiratory volume in 1 s (+160 mL vs. +30 mL; P = 0.009). Radiographic evidence of lung volume reduction 6 months after BLVR was significantly associated with improved survival (adjusted hazard ratio 0.020; 95% confidence interval 0.038-0.650; P = 0.010). Although pneumothorax was more common in the BLVR group (18.9% vs. 3.8%; P = 0.018), death was higher in the no-BLVR group (38.5% vs. 54.5%, P = 0.001), whereas other adverse events were comparable between the groups. Within the subset of 18 patients with PAL, the predominant causes of air-leak included spontaneous secondary pneumothorax (44.0%), parapneumonic effusion/empyema (22.2%), and post-lung resection surgery (16.7%). Following the treatment, the majority (77.8%) successfully had their chest tubes removed. Post-procedural complications were minimal, with two incidences of hemoptysis and one of empyema, all of which were effectively managed. CONCLUSIONS: Treatment with EBV provides substantial clinical benefits in the management of emphysema and PAL in the Asian population, suggesting a favorable outcome for this therapeutic approach.

[Catamenial pneumothorax with persistent air leak].

Catamenial pneumothorax is a spontaneous recurrent pneumothorax that occurs in women of reproductive age and in temporal relationship with the menses. It usually occurs within 24 hours before or 72 hours after the start of the menstrual cycle; however, multiple variations have been described in terms of the temporal relationship. To date, it is considered a rare condition; this may be justified by the limited available knowledge on this disease leading to misdiagnosis. Often, making a diagnosis of catamenial pneumothorax is complicated; it mainly depends on the medical history; also, it may be a surgical or histopathological diagnosis. Management strategies for catamenial pneumothorax may include combinations of hormonal therapy, pleurodesis, lung parenchyma resection, and diaphragm resection/repair. The aim of reporting this atypical case of catamenial pneumothorax is to highlight the relevance of having the adequate knowledge on this entity so it does not go unnoticed despite its apparent low incidence.

Methods of measurement for pneumothorax in pediatric patients: a systematic review.

Accurate measurement of pneumothorax (PTX) size is necessary to guide clinical decision making; however, there is no consensus as to which method should be used in pediatric patients. This systematic review seeks to identify and evaluate the methods used to measure PTX size with CXR in pediatric patients. A systematic review of the literature through 2021 following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was conducted using the following databases: Ovid/MEDLINE, Scopus, Cochrane Database of Controlled Trials, Cochrane Database of Systematic Reviews, and Google Scholar. Original research articles that included pediatric patients (< 18 years old) and outlined the PTX measurement method were included. 45 studies were identified and grouped by method (Kircher and Swartzel, Rhea, Light, Collins, Other) and societal guideline used. The most used method was Collins (n = 16; 35.6%). Only four (8.9%) studies compared validated methods. All found the Collins method to be accurate. Seven (15.6%) studies used a standard classification guideline and 3 (6.7%) compared guidelines and found significant disagreement between them. Pediatric-specific measurement guidelines for PTX are needed to establish consistency and uniformity in both research and clinical practice. Until there is a better method, the Collins method is preferred.

Refractory Pneumothorax Due to Cystic Pulmonary Metastasis of a Lowgrade Endometrial Stromal Sarcoma: A Case Report.

Low-grade endometrial stromal sarcoma (LG-ESS) is a rare uterine neoplasm. Computed tomography (CT) revealed the presence of multiple small bilateral pulmonary nodules in a 58-year-old woman 1 year after surgery for LG-ESS; the clinical diagnosis was pulmonary metastasis. Hormone therapy with progesterone was initiated, after which most of the solid nodules disappeared and some transformed into cystic lesions. Seven years after hormone therapy, the patient experienced repeated pneumothorax. The cause of the pneumothorax was perforation of a metastatic focus within the wall of a small subpleural cyst that was not evident on CT images.

Intraoperative mechanical ventilation and incidence of pneumothorax in lymphangioleiomyomatosis.

Patients with lymphangioleiomyomatosis (LAM) are considered high risk for most surgeries and require specific anesthetic considerations mainly because of the common spontaneous pneumothorax (PTX). To explore whether intraoperative mechanical ventilation could increase the risk of PTX in those patients, we included 12 surgical patients with LAM in this study, of whom four (33.3%) experienced postoperative PTX. According to our results, patients with higher CT grade, poorer pulmonary function, and a history of preoperative PTX might be more likely to develop postoperative PTX. However, intraoperative mechanical ventilation did not show obvious influence, which might help clinicians reconsider the perioperative management of LAM patients.

Occult solitary fibrous tumour of the pleura presenting as recurrent spontaneous pneumothorax.

A woman in her 30s, non-smoker, presented at the emergency department two times because of spontaneous pneumothorax. The first episode was treated with small bore catheter drainage, while during the second episode-occurring only 1 week later-thoracoscopic talcage was attempted. The postoperative course was characterised by slow clinical and radiological resolution, and recurrence 3 days after discharge. Eventually, multiportal video-assisted thoracoscopic exploration identified an interfissural solid mass. Resection and further work-up revealed the diagnosis of 'low-risk' solitary fibrous tumour (SFT) stage pT1N0M0. The interdisciplinary tumour board advised no adjuvant therapy. A CT thorax was scheduled in 1 year for follow-up. The patient was discharged without complications and has had no recurrences of pneumothorax at 6 months of follow-up. This report shows that SFT can easily be missed on initial presentation and should be considered in the differential diagnosis of pneumothorax, especially when frequently recurring.

Unmasking a hidden culprit: late-presenting congenital diaphragmatic hernia beyond infancy: A case report and literature review.

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a rare congenital anomaly with abnormal diaphragm development, typically diagnosed prenatally or soon after birth. Late-presenting CDH presents diagnostic challenges due to nonspecific symptoms that can lead to misdiagnoses. METHODS: This report discusses a 35-month-old female initially presenting with predominant gastrointestinal symptoms and minimal respiratory distress. Initial radiographic findings suggested a left tension pneumothorax, prompting further investigation. RESULTS: Subsequent diagnostic efforts revealed a Bochdalek-type left CDH, with several abdominal organs herniated into the thoracic cavity. The case was managed through laparotomy, where herniated contents were successfully repositioned into the abdominal cavity. This intervention underscores the need for high clinical suspicion and the importance of distinguishing between similar presentations, such as tension pneumothorax and tension gastrothorax, which require different management strategies. CONCLUSION: The case illustrates the importance of considering CDH in differential diagnoses for older pediatric patients with atypical symptoms. Early recognition and appropriate management are key to improving patient outcomes.

Chest tube removal at different gas flows in prolonged air leak: a randomized non-inferiority trial.

OBJECTIVES: To evaluate the safety and feasibility of removing drainage tubes at larger size of air leak in patients with prolonged air leak after pulmonary surgery. METHODS: Ninety-five patients who underwent pulmonary surgery with prolonged air leak in our centre were enrolled in this randomized controlled, single-centre, non-inferiority study. The drainage tube was clamped with a stable size of air leak observed over the last 6 h, which was quantified by gas flow rate using the digital drainage system. The control group (n = 48) and the study group (n = 46) had their drainage tube clamped at 0-20 ml/min and 60-80 ml/min, respectively. We continuously monitored clinical symptoms, conducted imaging and laboratory examinations, and decided whether to reopen the drainage tube. RESULTS: The reopening rate in the study group was not lower than that in the control group (2.08% vs 6.52%, P > 0.05). The absolute difference in reopening rate was 4.44% (95% confidence interval -0.038 to 0.126), with an upper limit of 12.6% below the non-inferiority margin (15%). There were significant differences in the length of stay [16.5 (13-24.75) vs 13.5 (12-19.25), P = 0.017] and the duration of drainage [12 (9.25-18.50) vs 10 (8-12.25), P = 0.007] between the control and study groups. No notable differences were observed in chest X-ray results 14 days after discharge or in the readmission rate. CONCLUSIONS: For patients with prolonged air leak, removing drainage tubes at larger size of air leak demonstrated similar safety compared to smaller size of air leak, and can shorten both length of stay and drainage duration. CLINICAL TRIAL REGISTRATION NUMBER: Name of registry: Gas flow threshold for safe removal of chest drainage in patients with alveolar-pleural fistula prolonged air leak after pulmonary surgery. Registration number: ChiCTR2200067120. URL: https://www.chictr.org.cn/.

An externally validated guide to anatomical interpretation using a direct-vision ('IRIS') feeding tube.

BACKGROUND & AIMS: Most of the 11.5 million feeding tubes placed annually in Europe and the USA are placed 'blind'. This carries a 1.6% risk that these tubes will enter the lung and 0.5% cause pneumothorax or pneumonia regardless of whether misplacement is identified prior to feeding. Tube placement by direct vision may reduce the risk of respiratory or oesophageal misplacement. This study externally validated whether an 'operator guide' would enable novice operators to differentiate the respiratory and alimentary tracts. METHODS: One IRIS tube was placed in each of 40 patients. Novice operators interpreted anatomical position using the built-in tube camera. Interpretation was checked from recorded images by consultant gastroenterologists and end-of-procedure checks using pH or X-ray checked by Radiologists and a consultant intensivist. RESULTS: The 40 patients were a median of 68y (IQR: 56-75), 70% male, mostly medical (65%), conscious (67.5%) and 70% had no artificial airway. Three tubes were removed due to failed placement. In the remaining 37 placements, novice operators identified the airway in 17 (45.9%) and airway + respiratory tract in 19 (51.4%), but redirected all these tubes into the oesophagus. By using direct vision to reduce the proportion of tubes near the airway or in respiratory tract from 0.514 to 0, operator discrimination between the respiratory and alimentary tracts was highly significant (0.514 vs 0: p < 0.0001, power >99.9% when significance = 0.05). In addition, organ boundaries (respiratory tract vs oesophagus, oesophagus vs stomach, stomach vs intestine) were identified in 100%. CONCLUSIONS: Novice operators, trained using the guide, identified all respiratory misplacements and accurately interpreted IRIS tube position. Guide-based training could enable widespread use of direct vision as a means to prevent tube-related complications.