A novel application of the Hyperflex™ tracheostomy tube for lung isolation in a patient with airway stoma after laryngectomy.

In patients who have undergone laryngectomy followed by permanent tracheostomy, managing the airway for one-lung ventilation during lung surgery may present a challenge for anaesthetists. This case report discusses a 45-year-old man with a permanent tracheostomy after a laryngectomy performed for laryngeal carcinoma 5 years ago. He was scheduled to undergo excision of a right bronchial mass for which one-lung ventilation was required. An adjustable Flange Hyperflex™ Tracheostomy tube (Bivona® Silicone Tracheostomy tube, Smiths Medical ASD, Inc., Gary, Indiana, USA) was used for this purpose and the tube was guided into the left main bronchus with a bronchoscope. Appropriate lung isolation was achieved using this technique, and there were no airway-related complications during or after the surgery. This case report shows that a Hyperflex™ tracheostomy tube can be successfully utilised in challenging airway scenarios in patients with a tracheostomy, where other options may not be feasible.

Resolvin E1 and Inhibition of BLT2 Signaling Attenuate the Inflammatory Response and Improve One-Lung Ventilation-Induced Lung Injury.

INTRODUCTION: One-lung ventilation (OLV) is a prevalently used technique to sustain intraoperative pulmonary function. Resolvin E1 (RvE1), a specialized pro-resolving lipid mediator, accelerates the resolution of inflammation in the lungs. However, its therapeutic effects on OLV-induced lung injury remain unclear. METHODS: We initially developed an OLV rat model and treated it with RvE1. Subsequently, we assessed the wet/dry ratio of the lung tissue, performed hematoxylin and eosin staining, and calculated the ratio of polymorphonuclear cells to white blood cells in the bronchoalveolar lavage fluid. Additionally, we assessed apoptosis, inflammatory factor levels, and lung permeability in the rat lung tissues in the RvE1 treated and untreated groups and explored the molecular mechanisms mediated by RvE1. RESULTS: Our results indicated that RvE1 alleviated lung injury and inflammation and improved lung tissue apoptosis and permeability in OLV rats. Moreover, RvE1 suppressed the expression of the BLT1/2 signaling pathway and its ligands. The use of BLT2 and BLT1 inhibitors (LY255283 and U-75302, respectively) enhanced RvE1's anti-inflammatory effects and reduced lung injury. Furthermore, synergistic treatment with the BLT2 inhibitor and RvE1 provided grater benefits by more effectively inhibiting the NF-kB, p38 MAPK, and ERK pathways. DISCUSSION: RvE1 and the inhibition of BLT2 signalling reduce the inflammatory response and mitigate OLV-induced lung injury. These findings suggest a novel therapeutic pathway for managing OLV-related complications.

Association between inspired oxygen fraction and development of postoperative pulmonary complications in thoracic surgery: a multicentre retrospective cohort study.

BACKGROUND: Limited data exist to guide oxygen administration during one-lung ventilation for thoracic surgery. We hypothesised that high intraoperative inspired oxygen fraction during lung resection surgery requiring one-lung ventilation is independently associated with postoperative pulmonary complications (PPCs). METHODS: We performed this retrospective multicentre study using two integrated perioperative databases (Multicenter Perioperative Outcomes Group and Society of Thoracic Surgeons General Thoracic Surgery Database) to study adult thoracic surgical procedures using one-lung ventilation. The primary outcome was a composite of PPCs (atelectasis, acute respiratory distress syndrome, pneumonia, respiratory failure, reintubation, and prolonged ventilation >48 h). The exposure of interest was high inspired oxygen fraction (FiO2), defined by area under the curve of a FiO2 threshold > 80%. Univariate analysis and logistic regression modelling assessed the association between intraoperative FiO2 and PPCs. RESULTS: Across four US medical centres, 141/2733 (5.2%) procedures conducted in 2716 patients (55% female; mean age 66 yr) resulted in PPCs. FiO2 was univariately associated with PPCs (adjusted OR [aOR]: 1.17, 95% confidence interval [CI]: 1.04-1.33, P=0.012). Logistic regression modelling showed that duration of one-lung ventilation (aOR: 1.20, 95% CI: 1.03-1.41, P=0.022), but not the time-weighted average FiO2 (aOR: 1.01, 95% CI: 1.00-1.02, P=0.165), was associated with PPCs. CONCLUSIONS: Our results do not support limiting the inspired oxygen fraction for the purpose of reducing postoperative pulmonary complications in thoracic surgery involving one-lung ventilation.

A Comparison of Conventional Rotating Method and Non-Rotating Method for Double-Lumen Tube Insertion Using a Customized Rigid J-Shaped Stylet for One-Lung Ventilation: A Randomized Controlled Trial.

Background: The conventional double-lumen tube (DLT) insertion method requires a rotatory maneuver that was developed using direct laryngoscopy and may not be optimal for video laryngoscopy. This study compared a new non-rotatory maneuver with the conventional method for DLT insertion using video laryngoscopy. Methods: Patients scheduled for thoracic surgery requiring one-lung ventilation were randomly assigned to either the rotating (R) or non-rotating (NR) method groups. All patients were intubated using a customized rigid J-shaped stylet, a video laryngoscope, and a left-sided silicone DLT. The conventional rotatory maneuver was performed in the R group. In the NR group, the stylet was inserted with its tip oriented anteriorly (12 o'clock direction) while maintaining the bronchial lumen towards the left (9 o'clock direction). After reaching the glottic opening, the tube was inserted using a non-rotatory maneuver, maintaining the initial orientation. The primary endpoint was the intubation time. Secondary endpoints included first-trial success rate, sore throat, hoarseness, and airway injury. Results: Ninety patients (forty-five in each group) were included. The intubation time was significantly shorter in the NR group compared to the R group (22.0 [17.0, 30.0] s vs. 28.0 [22.0, 34.0] s, respectively), with a median difference of 6 s (95% confidence interval [CI], 3-11 s; p = 0.017). The NR group had a higher first-attempt success rate and a lower incidence of sore throats. Conclusions: The non-rotatory technique with video laryngoscopy significantly reduced intubation time and improved first-attempt success rate, offering a viable and potentially superior alternative to the conventional rotatory technique.

Repercussions of SARS-CoV-2 infection on intrapulmonary shunt in patients undergoing one-lung ventilation.

BACKGROUND: Hypoxic pulmonary vasoconstriction is the most important regulatory mechanism by which right-to-left shunts decrease during one-lung ventilation (OLV), but the effects of pulmonary microarterial thrombosis and impaired HPV after SARS-CoV-2 infection on intrapulmonary shunt during OLV remain unknown. The aim of this study was to observe the changes of intrapulmonary shunt in patients undergoing thoracoscopic partial pneumonectomy at different periods after SARS-CoV-2 infection compared with patients without SARS-CoV-2 infection history. METHODS: A total of 80 patients who underwent elective thoracoscopic partial lung resection and were classified as American Society of Anaesthesiologists (ASA) grades I-II were selected and divided into 4 groups (n = 20 in each group): patients not infected with SARS-CoV-2 (Group A), patients infected with SARS-CoV-2 for 5-8 weeks (Group B), patients infected with SARS-CoV-2 for 9-12 weeks (Group C), and patients infected with SARS-CoV-2 for 13-16 weeks (Group D). For all patients, the same anaesthesia method was adopted, and anaesthesia was maintained with propofol, remifentanil, and cisatracurium. Radial artery and mixed venous blood gases were measured at 10 min of two-lung ventilation (TLV), 15 min of one-lung ventilation (OLV15), and 30 min of OLV (OLV30) in the lateral recumbent position to calculate the intrapulmonary shunt. Multiple linear regression analysis was employed to investigate the association between intrapulmonary shunt and SARS-CoV-2 infection. RESULTS: Qs/Qt at TLV was significantly higher in Groups B and C than in Group A (P < 0.05), and PaO2 at TLV was significantly lower in Groups B and C than in Group A (P < 0.05). Qs/Qt values at OLV15 and OLV30 were significantly higher in Group B, C or D than in Group A (P < 0.05), and PaO2 values at OLV15 and OLV30 were significantly lower in Groups B, C or D than in Group A (P < 0.05). Multiple linear regression analysis revealed that SARS-CoV-2 infection (95%CI -4.245 to -0.679, P = 0.007) was an independent risk factor for increased intrapulmonary shunt during TLV, while SARS-CoV-2 infection (95%CI 0.124 to 3.661, P = 0.036), exacerbation of COVID-19 clinical classification (95%CI -5.203 to -1.139, P = 0.003), and persistent symptoms (95%CI -12.122 to -5.522, P < 0.001) were independent risk factors for increased intrapulmonary shunt during OLV after SARS-CoV-2 infection. CONCLUSION: SARS-CoV-2 infection increased intrapulmonary shunt and reduced oxygenation. Although oxygenation improved at TLV after 13-16 weeks of infection, intrapulmonary shunt and oxygenation under OLV took longer to recover. TRIAL REGISTRATION: Chinese Clinical Trial Registry, Retrospectively registered, Full date of first registration: 17/05/2023, Registration number: ChiCTR2300071539.

Comparison of efficacy and safety of different suction pressure for speeding non-ventilated lung collapse in uniport video-assisted thoracoscopic surgery: a randomized-controlled trial.

BACKGROUND: The bronchial suction has been applied in speeding lung collapse. Low suction pressure may not speed lung collapse, but high pressure causes occult lung injury. The aim of the study was to explore efficacy and safety of different suction pressure for speeding lung collapse. METHODS: Eighty-four subjects undergoing uniport video-assisted thoracoscopic surgery (VATS) were randomly assigned for non-suction (Group 0), -10 cmH2O suction pressure (Group - 10), and - 30 cmH2O suction pressure (Group - 30). The primary outcome were the lung collapse scores (LCS) at 0 min (T0) after the visualization of the lung using a 10-point visual analogue scale and area under the curve (AUC) of LCS over time. The secondary outcomes included disconnection from the ventilator, the assessment of occult lung injury using NOS-3 expression, histologic scores of lung injury, and lung W/D weight ratio, intraoperative hypoxemia, the incidence of perioperative pulmonary complications. RESULTS: Both the LCS at T0 and AUC analysis showed that compared with Group 0, Group - 10 and Group - 30 significantly achieved good lung collapse (P < 0.05), but no difference between Group - 10 and Group - 30. Four patients in Group 0 were treated with disconnection maneuver. The assessment of occult lung injury showed no differences. CONCLUSIONS: Applying - 10 cmH2O suction pressure for 1 min when pleural incision is a relatively safe method to promote lung collapse without the occurrence of occult lung injury. TRIAL REGISTRATION: Chinese Clinical Trial Registry number, ChiCTR2200062991. Registered on 26/08/2022.

Effect of optimizing cerebral oxygen saturation on postoperative delirium in older patients undergoing one-lung ventilation for thoracoscopic surgery.

OBJECTIVES: This randomized controlled trial investigated whether the regional cerebral oxygenation saturation (rScO2)-guided lung-protective ventilation strategy could improve brain oxygen and reduce the incidence of postoperative delirium (POD) in patients older than 65 years. METHODS: This randomized controlled trial enrolled 120 patients undergoing thoracic surgery who received one-lung ventilation (OLV). Patients were randomly assigned to the lung-protective ventilation group (PV group) or rScO2-oriented lung-protective ventilation group (TPV group). rScO2 was recorded during the surgery, and the occurrence of POD was assessed. RESULTS: The incidence of POD 3 days after surgery-the primary outcome-was significantly lower in the TPV group (23.3% versus 8.5%). Meanwhile, the levels of POD-related biological indicators (S100ß, neuron-specific enolase, tumor necrosis factor-α) were lower in the TPV group. Considering the secondary outcomes, both groups exhibited a lower oxygenation index after OLV, whereas partial pressure of carbon dioxide and mean arterial pressure were significantly increased in the TPV group. In addition, minimum rScO2 during surgery and mean rScO2 were higher in the TPV group than in the PV group. CONCLUSION: Continuous intraoperative monitoring of brain tissue oxygenation and active intervention measures guided by cerebral oxygen saturation are critical for improving brain metabolism and reducing the risk of POD.

Goal-Directed Fluid Therapy Using Pulse Pressure Variation in Thoracic Surgery Requiring One-Lung Ventilation: A Randomized Controlled Trial.

Background: Intraoperative fluid management based on pulse pressure variation has shown potential to reduce postoperative pulmonary complications (PPCs) and improve clinical outcomes in various surgical settings. However, its efficacy and safety have not been assessed in patients undergoing thoracic surgery with one-lung ventilation. Methods: Patients scheduled for pulmonary lobectomy using uniportal video-assisted thoracic surgery approach were randomly assigned to two groups. In the PPV group, fluid administration was guided by the pulse pressure variation parameter, while in the near-zero group, it was guided by conventional hemodynamic parameters. The primary outcome was the partial pressure of oxygen (PaO2)/ fraction of inspired oxygen (FiO2) ratio 15 min after extubation. The secondary outcomes included extubation time, the incidence of postoperative pulmonary complications in the first three postoperative days, and the length of hospital stay. Results: The PaO2/FiO2 ratio did not differ between the two groups (364.48 ± 38.06 vs. 359.21 ± 36.95; p = 0.51), although patients in the PPV group (n = 44) received a larger amount of both crystalloids (1145 ± 470.21 vs. 890 ± 459.31, p = 0.01) and colloids (162.5 ± 278.31 vs 18.18 ± 94.68, p = 0.002) compared to the near-zero group (n = 44). No differences were found in extubation time, type and number of PPCs, and length of hospital stay. Conclusions: PPV-guided fluid management in thoracic surgery requiring one-lung ventilation does not improve pulmonary gas exchange as measured by the PaO2/FiO2 ratio and does not seem to offer clinical benefits. Additionally, it results in increased fluid administration compared to fluid management based on conventional hemodynamic parameters.

Effects of Dexmedetomidine in Improving Oxygenation and Reducing Pulmonary Shunt in High-Risk Pediatric Patients Undergoing One-Lung Ventilation for Thoracic Surgery: A Double-Blind Randomized Controlled Trial.

Background and objectives Pediatric thoracic surgery has unique considerations due to the immaturity of the respiratory system anatomically and physiologically, which presents technical and pharmacological considerations, including the very common technique of one-lung ventilation (OLV), which causes serious complications in children. Therefore, we investigated the effects of dexmedetomidine on oxygenation and pulmonary shunt fraction (Qs/Qt) in high-risk pediatric patients undergoing OLV for thoracic surgery. This randomized controlled trial aimed to investigate dexmedetomidine's effect on the partial pressure of arterial oxygen (PaO2) and pulmonary shunt fraction (Qs/Qt). Methods A total of 63 children underwent thoracic surgery with OLV and were divided into two groups. The dexmedetomidine group (group Dex, n = 32) received dexmedetomidine (0.4 µg/kg/hour), and the placebo group (group placebo, n = 31) received normal saline. Two arterial and central venous blood samples were taken for arterial and venous blood gas analysis at four time points: T1 (10 minutes after mechanical ventilation of total lung ventilation), T2 (10 minutes after OLV), T3 (60 minutes after OLV), and T4 (20 minutes after the end of OLV). At these intervals, the following parameters were measured: PaO2, Qs/Qt, mean arterial pressure (MAP), heart rate (HR), and peak inspiratory pressure (PIP). Results The two groups had no significant differences in FEV1/FVC and baseline pulmonary shunt fraction (Qs/Qt). Dexmedetomidine significantly improved PaO2 compared with placebo during OLV (T2 and T3). There was a significant decrease in Qs/Qt compared with placebo during OLV (T2, T3, and T4). There was a decrease in PIP compared with placebo during OLV (T2 and T3). No statistically significant differences in MAP or HR were observed between the groups. Conclusion Infusion of dexmedetomidine during OLV in high-risk pediatric thoracic surgery reduces shunt and pulmonary shunt fraction Qs/Qt, improves PaO2 and body oxygenation, reduces PIP and pressure load, and maintains hemodynamic stability (MAP, HR).

Peri-Operative Anesthetic Management of Left Atrial-Esophageal Fistula.

Atrial-esophageal fistulas are rare and potentially fatal complications that can occur from radiofrequency ablation for the treatment of atrial fibrillation. Due to the proximity of the right atrium to the esophagus, thermal injuries can involuntarily lead to connections between the heart and esophagus. In this case study, a 67-year-old male developed an atrial-esophageal fistula following atrial fibrillation ablation. After discharge, the patient first presented with melena with a range of complications including aspiration, fever, atrial fibrillation, and neurological symptoms. The fistula was repaired promptly after diagnosis requiring meticulous planning by the anesthesia and surgical teams. The major consideration from anesthesiology was providing adequate oxygenation during one-lung ventilation via continuous positive airway pressure on the non-dependent lung. This case also highlights the need for recognizing and managing potential complications associated with catheter ablation procedures. A thorough understanding of these rare but critical events is essential for optimizing patient outcomes and minimizing mortality rates, and physicians and healthcare professionals must remain vigilant regarding such complications.

Cardiopulmonary crisis caused by bronchial blocker malposition in a patient with aberrant tracheal anatomy: a case report.

BACKGROUND: Double-lumen tubes (DLTs) and bronchial blockers (BBs) can be used to establish one-lung ventilation (OLV) for thoracic surgery. BBs are a good alternative when DLTs are not suitable or patients have difficult airways. However, BBs are more prone to malposition, leading to adverse events. CASE PRESENTATION: We present a 68-year-old male patient who was scheduled for thoracoscopic left lower lobectomy. The patient was not expected to have airway malformation preoperatively. When the DLT could not be inserted into the bronchus after general anesthesia induction, we used a BB to perform OLV. During surgery, malposition of the BB resulted in the development of an "incomplete balloon valve", leading to a cardiopulmonary crisis. CONCLUSIONS: Previewing chest computed tomography scans to assess the airway anatomy before thoracic surgery is essential. Three-dimensional reconstruction of the airway can provide a more intuitive assessment of airway anatomy. During OLV with BBs, we should pay attention to balloon malposition to prevent cardiopulmonary crises.

Anesthetic Management of Thoracoscopic Pulmonary Cystectomy in a Patient With Fontan Circulation and Disturbed Lung Inflation During Leakage Testing: A Case Report.

Congenital heart disease may require multiple cardiac surgeries during childhood. Subsequent non-cardiac surgeries increase the perioperative bleeding and hypoxia because of changes in circulation. An 18-year-old male patient with a history of multiple cardiac interventions, including Fontan surgery, underwent a thoracoscopic right lung suture and coverage for recurrent right spontaneous pneumothorax under general anesthesia with one lung ventilation (OLV). The superior dorsal and inferior lobes, which were inflatable before surgery, failed to expand during leakage testing. The trachea's condition was examined using a flexible bronchoscope, and no obstructions were found. A thoracic drainage catheter was inserted, and the lower lobe was dilated from outside the body using negative pressure control in a sealed environment. In the patient with previously treated Fontan circulation, both lungs were expanded by inserting a thoracic catheter during thoracoscopic right lung suture and maintaining negative external pressure.

Effects of starting one lung ventilation and applying individualized PEEP right after patients are placed in lateral decubitus position on intraoperative oxygenation for patients undergoing thoracoscopic pulmonary lobectomy: study protocol for a randomized controlled trial.

BACKGROUND: For patients receiving one lung ventilation in thoracic surgery, numerous studies have proved the superiority of lung protective ventilation of low tidal volume combined with recruitment maneuvers (RM) and individualized PEEP. However, RM may lead to overinflation which aggravates lung injury and intrapulmonary shunt. According to CT results, atelectasis usually forms in gravity dependent lung regions, regardless of body position. So, during anesthesia induction in supine position, atelectasis usually forms in the dorsal parts of lungs, however, when patients are turned into lateral decubitus position, collapsed lung tissue in the dorsal parts would reexpand, while atelectasis would slowly reappear in the lower flank of the lung. We hypothesize that applying sufficient PEEP without RM before the formation of atelectasis in the lower flank of the lung may beas effective to prevent atelectasis and thus improve oxygenation as applying PEEP with RM. METHODS: A total of 84 patients scheduled for elective pulmonary lobe resection necessitating one lung ventilation will be recruited and randomized totwo parallel groups. For all patients, one lung ventilation is initiated the right after patients are turned into lateral decubitus position. For patients in the study group, individualized PEEP titration is started the moment one lung ventilation is started, while patients in the control group will receive a recruitment maneuver followed by individualized PEEP titration after initiation of one lung ventilation. The primary endpoint will be oxygenation index measured at T4. Secondary endpoints will include intrapulmonary shunt, respiratory mechanics, PPCs, and hemodynamic indicators. DISCUSSION: Numerous previous studies compared the effects of individualized PEEP applied alone with that applied in combination with RM on oxygenation index, PPCs, intrapulmonary shunt and respiratory mechanics after atelectasis was formed in patients receiving one lung ventilation during thoracoscopic surgery. In this study, we will apply individualized PEEP before the formation of atelectasis while not performing RM in patients allocated to the study group, and then we're going to observe its effects on the aspects mentioned above. The results of this trial will provide a ventilation strategy that may be conductive to improving intraoperative oxygenation and avoiding the detrimental effects of RM for patients receiving one lung ventilation. TRIAL REGISTRATION: www.Chictr.org.cn ChiCTR2400080682. Registered on February 5, 2024.

Effect of patient position on the success rate of placing triple-cuffed double lumen endotracheal tubes: a two-center interventional observational study.

Background: Double-lumen endotracheal tubes (DLT) are essential for one-lung ventilation during thoracic surgery. Bronchoscopy is crucial for correct placement of a DLT to avoid complications such as hypoxemia. This study evaluated the effectiveness of the triple-cuffed DLT (tcDLT) in the supine and lateral positions for correct placement without bronchoscopic guidance. Methods: This prospective observational study included 167 patients scheduled for elective thoracic surgery requiring one-lung ventilation. The incidence of successful placement of left-sided tcDLTs was compared between the supine and lateral decubitus positions under bronchoscopic surveillance. Successful tcDLT placement was defined as the placement of the proximal end of the bronchial cuff within 5 mm of the carina. Results: Among 153 patients who completed the study, the successful tcDLT placement rate in the lateral position (70.6%) was significantly higher than that in the supine position (50.3%). The rate of difference was 20.3% (95% confidence interval [CI], 10.6-29.9%). The extended successful placement rate, including slightly deeper placements, showed no significant differences between the positions (88.9%; 95% CI, 83.9‒93.9% in supine, 86.3%; 95% CI, 80.8‒91.7% in lateral). Conclusions: tcDLT facilitates correct tube placement in both the supine and lateral positions, with a higher lateral success rate. This finding supports the idea that tcDLTs offer a reliable alternative for lung separation when bronchoscopy is not feasible.

Anesthetic Management of Large Bronchogenic Cyst With Severe Tracheal Compression in Adults: A Case Report.

Bronchogenic cysts (BCs) are a congenital anomaly, forming fluid-filled sacs in the bronchial tree during fetal development, and are relatively rare in adults. Patients with large BCs in the mediastinum presenting with severe tracheal compression pose a significant challenge to anesthesiologists. The confined and narrow space of the mediastinum exacerbates the compression effect on surrounding structures, leading to potential respiratory or cardiovascular collapse during anesthesia and postoperatively. Herein, we report the stepwise anesthetic management of a patient with a BC in the paratracheal region of superior mediastinum, causing near-complete tracheal compression, scheduled for right posterolateral thoracotomy and tumor excision. The patient presented with dyspnea, chest pain, cough, and severe tracheal compression necessitating meticulous airway management. Utilizing awake fiberoptic intubation with a single-lumen endotracheal tube and one-lung ventilation facilitated by an EZ bronchial blocker, we successfully secured the airway, provided ideal surgical conditions through lung deflation, and ensured perioperative safety. This case underscores the crucial role of comprehending the underlying pathophysiology, anticipating complications, and meticulously planning, preparing, and executing strategies for airway management and perioperative care in patients with mediastinal masses leading to significant tracheal compression.

Effect of flow-optimized pressure control ventilation-volume guaranteed (PCV-VG) on postoperative pulmonary complications: a consort study.

BACKGROUND: Postoperative pulmonary complications (PPCs) after one-lung ventilation (OLV) significantly impact patient prognosis and quality of life. OBJECTIVE: To study the impact of an optimal inspiratory flow rate on PPCs in thoracic surgery patients. METHODS: One hundred eight elective thoracic surgery patients were randomly assigned to 2 groups in this consort study (control group: n = 53 with a fixed inspiratory expiratory ratio of 1:2; and experimental group [flow rate optimization group]: n = 55). Measurements of Ppeak, Pplat, PETCO2, lung dynamic compliance (Cdyn), respiratory rate, and oxygen concentration were obtained at the following specific time points: immediately after intubation (T0); immediately after starting OLV (T1); 30 min after OLV (T2); and 10 min after 2-lung ventilation (T4). The PaO2:FiO2 ratio was measured using blood gas analysis 30 min after initiating one-lung breathing (T2) and immediately when OLV ended (T3). The lung ultrasound score (LUS) was assessed following anesthesia and resuscitation (T5). The occurrence of atelectasis was documented immediately after the surgery. PPCs occurrences were noted 3 days after surgery. RESULTS: The treatment group had a significantly lower total prevalence of PPCs compared to the control group (3.64% vs. 16.98%; P = 0.022). There were no notable variations in peak airway pressure, airway plateau pressure, dynamic lung compliance, PETCO2, respiratory rate, and oxygen concentration between the two groups during intubation (T0). Dynamic lung compliance and the oxygenation index were significantly increased at T1, T2, and T4 (P < 0.05), whereas the CRP level and number of inflammatory cells decreased dramatically (P < 0.05). CONCLUSION: Optimizing inspiratory flow rate and utilizing pressure control ventilation -volume guaranteed (PCV-VG) mode can decrease PPCs and enhance lung dynamic compliance in OLV patients.

The feasibility and accuracy of the method for selecting the optimal size of double-lumen tube in thoracic surgery: a prospective, randomized controlled trial.

Double-lumen tubes (DLTs) are commonly used for one-lung ventilation (OLV) in thoracic surgery and the selection of an optimal size of DLTs is still a humongous task. The purpose of this study was to assess the feasibility and accuracy of the method for selecting an optimal size of DLTs in thoracic surgery. Sixty adult patients requiring a left side double-lumen tube (LDLT) for elective thoracoscopic surgery were included in this study. All patients were randomly allocated to the following two groups: Cuffs Collapsed group (CC group, n = 30) and Cuffs Inflated group (CI group, n = 30). In the Cuffs Collapsed group, the outer diameter of LDLT (the outer diameter of the tracheal and bronchial cuffs when they were collapsed as the outer diameter of the LDLT) matched with the inner diameter of the trachea and bronchus measured by the anesthesiologist on the chest CT slice; In the Cuffs Inflated group, the outer diameter of LDLT (the outer diameter of the tracheal and bronchial cuffs when they were inflated as the outer diameter of the LDLT) matched with the inner diameter of the trachea and bronchus measured by the anesthesiologist on the chest CT slice. The primary outcomes were the incidences of airway complications postoperative such as hoarseness and sore throat. The time of intubation and alignment, the incidences of LDLT displacement and adjustment, the peak airway pressure, the plateau airway pressure and the end-tidal carbon dioxide were also recorded. The incidences of airway complications postoperative such as sore throat and hoarseness were lower in the CI group than the CC group (P < 0.05), the intubation times was shorter in the CI group than the CC group (P < 0.05), while the peak airway pressure, the plateau airway pressure and the end-tidal carbon dioxide during two-lung ventilation and one-lung ventilation were no significant difference between two groups (P > 0.05). The method which matched the inner diameter of the trachea and bronchus measured on chest CT slice with the outer diameter of the tracheal and bronchial cuffs when they were inflated to select an appropriate size of LDLT can reduce the incidence of airway complications.Trials registration: Clinical Trials: gov. no. NCT05739318. Registered at https://classic.clinicaltrials.gov 22/02/2023.

A novel approach to calculate the required volume of air for bronchial blockers in young children.

INTRODUCTION: Bronchial blocker balloons inflated with small volumes of air increase balloon pressure, involving a risk of airway injury especially in young children. However, there are no established guidelines regarding the appropriate volumes of air required to provide safe bronchial occlusion. METHODS: This study aimed to introduce a novel method for calculating the amount of air required for safe bronchial blocker balloon occlusion for one lung anesthesia in young children. We included 79 pediatric patients who underwent video-assisted thoracoscopic surgery at our hospital. Preoperatively, the balloon pressure and corresponding diameter of 5F bronchial blockers inflated with different volumes of air were measured. Intraoperatively, bronchial diameters measured by computerized tomographic scans were matched to the ex vivo measured balloon diameters. The quality of lung isolation, incidence of balloon repositioning, and airway injury were documented. Postoperatively, airway injury was evaluated through fiberoptic bronchoscopy. RESULTS: Balloon pressure and balloon diameter showed linear and nonlinear correlations with volume, respectively. The median lengths of the right and left mainstem bronchi were median (interquartile range) range: 5.3 mm (4.5-6.3) 2.7-8.15 and 21.8 (19.6-23.4) 14-29, respectively. Occluding the left mainstem bronchus required <1 mL of air, with a balloon pressure of 27 cm H2O. The isolation quality was high with no case of mucosal injury or displacement. Occluding the right mainstem bronchus required a median air volume of 1.3 mL, with a median balloon pressure of 44 cm H2O. One patient had poor lung isolation due to a tracheal bronchus and another developed mild and transient airway injury. CONCLUSION: The bronchial blocker cuff should be regarded as a high-pressure balloon. We introduced a new concept for safe bronchial blocker balloon occlusion for one-lung ventilation in small children.

The Hemodynamic Changes Induced by Lung Recruitment Maneuver to Predict Fluid Responsiveness in Children during One Lung Ventilation-A Prospective Observational Study.

BACKGROUND: The prediction of fluid responsiveness in critical patients helps clinicians in decision making to avoid either under- or overloading of fluid. This study was designed to determine whether lung recruitment maneuver (LRM) would have an effect on the predictability of fluid responsiveness by the changes of hemodynamic parameters in pediatric patients who were receiving lung-protective ventilation and one-lung ventilation (OLV). METHODS: A total of 34 children, aged 1-6 years old, scheduled for heart surgeries via right thoracotomy were enrolled. Patients were anesthetized and OLV with lung-protection ventilation settings was established, and then, positioned on left lateral decubitus. LRM and volume expansion (VE) were performed in sequence. Heart rate (HR), systolic arterial pressure (SAP), mean arterial pressure (MAP) diastolic arterial pressure (DAP), stroke volume (SV), stroke volume variation (SVV), and pulse pressure variation (PPV) were recorded via an A-line based monitor system at the following time points: before and after LRM (T1 and T2) and before and after VE (T3 and T4). An increase in stroke volume (SV) or mean arterial pressure (MAP) of ≥10% following fluid loading identified fluid responders. The predictability of fluid responsiveness by the changes of SV (ΔSVLRM) and MAP (ΔMAPLRM) after LRM and VE were statistically evaluated by receiver operating characteristic curves [area under the curves (AUC)]. RESULTS: SVs in all patients were significantly decreased after LRM (p < 0.01) and then, increased and returned to baseline after VE (p < 0.01). In total, 16 out of 34 patients who were fluid responders had significantly lower SV after LRM compared to that in fluid non-responders. The area under the receiver operating characteristic curves for ΔSVLRM was 0.828 (95% confidence interval [CI], 0.660 to 0.935; p < 0.001) and it indicated that ΔSVLRM was able to predict the fluid responsiveness of pediatric patients. MAPs in all patients were also decreased significantly after LRM, and 12 of them fell into the category of fluid responders after VE. Statistically, ΔMAPLRM did not predict fluid responsiveness when LRM was considered as an influential factor (p = 0.07). CONCLUSIONS: ΔSVLRM, but not ΔMAPLRM, showed great reliability in the prediction of the fluid responsiveness following VE in children during one-lung ventilation with lung-protective settings. TRIAL REGISTRATION: ChiCTR2300070690.

Unveiling the protective role of sevoflurane in video-assisted thoracoscopic surgery associated-acute lung injury: Inhibition of ferroptosis.

Acute lung injury (ALI) frequently occurs after video-assisted thoracoscopic surgery (VATS). Ferroptosis is implicated in several lung diseases. Therefore, the disparate effects and underlying mechanisms of the two commonly used anesthetics (sevoflurane (Sev) and propofol) on VATS-induced ALI need to be clarified. In the present study, enrolled patients were randomly allocated to receive Sev (group S) or propofol anesthesia (group P). Intraoperative oxygenation, morphology of the lung tissue, expression of ZO-1, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), superoxide dismutase (SOD), glutathione (GSH), Fe2+, glutathione peroxidase 4 (GPX4), and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/nuclear factor erythroid-2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway in the lung tissue as well as the expression of TNF-α and IL-6 in plasma were measured. Postoperative complications were recorded. Of the 85 initially screened patients scheduled for VATS, 62 were enrolled in either group S (n = 32) or P (n = 30). Compared with propofol, Sev substantially (1) improved intraoperative oxygenation; (2) relieved histopathological lung injury; (3) increased ZO-1 protein expression; (4) decreased the levels of TNF-α and IL-6 in both the lung tissue and plasma; (5) increased the contents of GSH and SOD but decreased Fe2+ concentration; (6) upregulated the protein expression of p-AKT, Nrf2, HO-1, and GPX4. No significant differences in the occurrence of postoperative outcomes were observed between both groups. In summary, Sev treatment, in comparison to propofol anesthesia, may suppress local lung and systemic inflammatory responses by activating the PI3K/Akt/Nrf2/HO-1 pathway and inhibiting ferroptosis. This cascade of effects contributes to the maintenance of pulmonary epithelial barrier permeability, alleviation of pulmonary injury, and enhancement of intraoperative oxygenation in patients undergoing VATS.