Two-lung ventilation with artificial pneumothorax on cerebral desaturation and early postoperative cognitive outcome: a randomized controlled trial.

BACKGROUND: The effect of two lung ventilation (TLV) with carbon dioxide artificial pneumothorax on cerebral desaturation and postoperative neurocognitive changes in elderly patients undergoing elective minimally invasive esophagectomy (MIE) is unclear. OBJECTIVES: The first aim of this study was to compare the effect of TLV and one lung ventilation (OLV) on cerebral desaturation. The second aim was to assess changes in early postoperative cognitive outcomes of two ventilation methods. METHODS: This prospective, randomized, controlled trial enrolled patients 65 and older scheduled for MIE. Patients were randomly assigned (1:1) to TLV group or OLV group. The primary outcome was the incidence of cerebral desaturation events (CDE). Secondary outcomes were the cumulative area under the curve of desaturation for decreases in regional cerebral oxygen saturation (rSO2) values below 20% relative to the baseline value (AUC.20) and the incidence of delayed neurocognitive recovery. RESULTS: Fifty-six patients were recruited between November 2019 and August 2020. TLV group had a lower incidence of CDE than OLV group [3 (10.71%) vs. 13 (48.14%), P = 0.002]. TLV group had a lower AUC.20 [0 (0-35.86) % min vs. 0 (0-0) % min, P = 0.007], and the incidence of delayed neurocognitive recovery [2 (7.4%) vs. 11 (40.7%), P = 0.009] than OLV group. Predictors of delayed neurocognitive recovery on postoperative day 7 were age (OR 1.676, 95% CI 1.122 to 2.505, P = 0.006) and AUC.20 (OR 1.059, 95% CI 1.025 to 1.094, P < 0.001). CONCLUSION: Compared to OLV, TLV had a lower incidence of CDE and delayed neurocognitive recovery in elderly patients undergoing MIE. The method of TLV combined with carbon dioxide artificial pneumothorax may be an option for these elderly patients. Chinese Clinical Trial Registry (identifier: ChiCTR1900027454).

Cardiorespiratory impact of intrathoracic pressure overshoot during artificial carbon dioxide pneumothorax: a randomized controlled study.

BACKGROUND: The aim of this study is to evaluate cardiovascular and respiratory effects of intrathoracic pressure overshoot (higher than insufflation pressure) in patients who underwent thoracoscopic esophagectomy procedures with carbon dioxide (CO2) pneumothorax. METHODS: This prospective research included 200 patients who were scheduled for esophagectomy from August 2016 to July 2020. The patients were randomly divided into the Stryker insufflator (STR) group and the Storz insufflator (STO) group. We recorded the changes of intrathoracic pressure, peak airway pressure, blood pressure, heart rate and central venous pressure (CVP) during artificial pneumothorax. The differences in blood gas analysis, the administration of vasopressors and the recovery time were compared between the two groups. RESULTS: We found that during the artificial pneumothorax, intrathoracic pressure overshoot occurred in both the STR group (8.9 mmHg, 38 times per hour) and the STO group (9.8 mmHg, 32 times per hour). The recorded maximum intrathoracic pressures were up to 58 mmHg in the STR group and 51 mmHg in the STO group. The average duration of intrathoracic pressure overshoot was significantly longer in the STR group (5.3 ± 0.86 s) vs. the STO group (1.2 ± 0.31 s, P < 0.01). During intrathoracic pressure overshoot, a greater reduction in systolic blood pressure (SBP) (5.6 mmHg vs. 1.1 mmHg, P < 0.01), a higher elevation in airway peak pressure (4.8 ± 1.17 cmH2O vs. 0.9 ± 0.41 cmH2O, P < 0.01), and a larger increase in CVP (8.2 ± 2.86 cmH2O vs. 4.9 ± 2.35 cmH2O, P < 0.01) were observed in the STR group than in the STO group. Vasopressors were also applied more frequently in the STR group than in the STO group (68% vs. 43%, P < 0.01). The reduction of SBP caused by thoracic pressure overshoot was significantly correlated with the duration of overshoot (R = 0.76). No obvious correlation was found between the SBP reduction and the maximum pressure overshoot. CONCLUSIONS: Intrathoracic pressure overshoot can occur during thoracoscopic surgery with artificial CO2 pneumothorax and may lead to cardiovascular adverse effects which highly depends on the duration of the pressure overshoot. TRIAL REGISTRATION: Clinicaltrials.gov ( NCT02330536 ; December 24, 2014).

Artificial pneumothorax improves radiofrequency ablation of pulmonary metastases of hepatocellular carcinoma close to mediastinum.

BACKGROUND: To investigate the feasibility, safety and efficacy of percutaneous radiofrequency ablation (RFA) of pulmonary metastases from hepatocellular carcinoma (HCC) contiguous with the mediastinum using the artificial pneumothorax technique. METHOD: A total of 40 lesions in 32 patients with pulmonary metastases from HCC contiguous with the mediastinum accepted RFA treatment from August 2014 to May 2018 via the artificial pneumothorax technique. After ablation, clinical outcomes were followed up by contrast enhanced CT. Technical success, local tumor progression (LTP), intrapulmonary distant recurrence (IDR), and adverse events were evaluated. Overall survival (OS) and local tumor progression free survival (LTPFS) were recorded for each patient. RESULTS: The tumor size was 1.4 ± 0.6 cm in diameter. RFA procedures were all successfully performed without intra-ablative complications. Technical success was noted in 100% of the patients. Five cases of LTP and 8 cases of IDR occurred following the secondary RFA for treatment. Slight pain was reported in all patients. No major complications were observed. The 1, 2, and 3-year LTPFS rates were 90.6, 81.2, and 71.8%, and the 1, 2, and 3-year OS rates were 100, 100 and 87.5%, respectively. CONCLUSION: Artificial pneumothorax adjuvant RFA is a feasible, safe, and efficient method for treatment of pulmonary metastases from HCC contiguous with the mediastinum.

Efficacy of artificial pneumothorax under two-lung ventilation in video-assisted thoracoscopic surgery for esophageal cancer.

BACKGROUND: One-lung ventilation (OLV) is the standard and widely applied ventilation approach used in video-assisted thoracoscopic surgery for esophageal cancer (VATS-e). To address the disadvantages of OLV with respect to difficulties in intubation and induction, as well as the risk of respiratory complications, two-lung ventilation (TLV) with artificial pneumothorax has been introduced for use in VATS-e. However, no studies have yet compared TLV and OLV with postoperative infection and inflammation in the prone position over time postoperatively. Here, we investigated the efficacy of TLV in patients undergoing VATS-e in the prone position. METHODS: Between April 2010 and December 2016, 119 patients underwent VATS-e under OLV or TLV with carbon dioxide insufflation. Clinical characteristics, surgical outcomes, and postoperative outcomes, including oxygenation and systemic inflammatory responses, were compared between patients who underwent OLV and those who underwent TLV. RESULTS: Clinical characteristics other than pT stage were comparable between groups. The TLV group had shorter thoracic operation time than the OLV group. No patients underwent conversion to open thoracotomy. The PaO2/FiO2 ratios of the TLV group on postoperative day (POD) 5 and on POD7 were significantly higher than those of the OLV group. C-reactive protein levels on POD7 were lower in the TLV group than in the OLV group. There were no significant differences with respect to postoperative complications between the OLV and TLV groups. In the TLV group, the white blood cell count on POD7 was significantly lower than that in the OLV group; body temperature showed a similar trend immediately after surgery and on POD1. CONCLUSIONS: In this study, we demonstrated that, compared with OLV, TLV in the prone position provides better oxygenation and reduced inflammation in the postoperative course. Accordingly, TLV might be more useful than OLV for ventilation during esophageal cancer surgery.

Artificial pneumothorax: a safe and simple method to relieve pain during microwave ablation of subpleural lung malignancy.

BACKGROUND: Microwave ablation has been extensively used for eliminating pulmonary tumors; however, it is usually associated with severe pain under local anesthesia. Decreasing the power and shortening the ablation time can help to relieve the pain; however, this leads to incomplete ablation and an increasing recurrence rate. This research aims to employ an artificial pneumothorax to increase both the curative effect and pain relief during the ablation procedure. MATERIAL AND METHODS: From July 2013 to January 2015, nine patients presenting with 10 subpleural lung tumors (age: 44-78 years) with a high possibility of severe pain underwent the artificial pneumothorax during microwave ablation. The pain assessment scores and complications induced by the artificial pneumothorax were recorded and analyzed by a CT scan follow-up. RESULTS: The tumors of the nine patients were eliminated successfully using microwave ablation with artificial pneumothorax under local anesthesia. The pain caused by the ablation was relieved to a great extent with an average rate of 94.66% (range: 63.3%-100%) and all tumors were ablated completely. No severe complications occurred after the operation. CONCLUSIONS: The artificial pneumothorax is a reliable therapy to improve the curative effect of microwave ablation under local anesthesia by relieving the pain of the patients.

Impact of artificial capnothorax on coagulation in patients during video-assisted thoracoscopic esophagectomy for squamous cell carcinoma.

BACKGROUND: Compared with the lung isolation using double-lumen endobronchial tube intubation, the artificial capnothorax using single-lumen endotracheal tube intubation has shown to be a safe, more convenient, and cost-effective procedure for thoracoscopic esophagectomy. However, the impact of capnothorax on coagulation is not well defined. Herein, we evaluate the impact of a capnothorax on coagulation and fibrinolysis in patients who undergoing thoracoscopic esophagectomy. METHODS: Between March 2014 and August 2014, 24 patients underwent thoracoscopic esophagectomies for esophageal cancer with the procedure of artificial capnothorax (group P); we also performed 24 thoracoscopic esophagectomy cases without using capnothorax (group N). The demographics and arterial blood gas, as well as the parameters of coagulation and fibrinolysis, of the two groups were analyzed. RESULTS: The pH value of group P after CO2 insufflation was significantly lower than in group N (P < 0.05), and the partial pressure of carbon dioxide (PaCO2) was significantly increased compared with group N (P < 0.05). The R and K values after CO2 insufflation were significantly longer than before anesthesia (P < 0.05), and both α angle and MA value after CO2 insufflation were significantly lower than those before anesthesia (P < 0.05). No significant differences in R value, K value, α angle, or MA value were observed between pre-anesthesia and termination of capnothorax. No significant difference in LY30 data was found between different groups (P > 0.05). CONCLUSION: Artificial capnothorax in patients receiving endoscopic resection of esophageal carcinoma had a significant impact on coagulation. These patients showed significant impairments in coagulation not observed in patients without artificial capnothorax.

Bilateral Endoscopic Lung Volume Reduction in Patients with Severe Emphysema.

Reducing hyperinflated areas in chronic obstructive pulmonary disease, either surgically or endoscopically, leads to improvement of functional parameters. It is unclear if bilateral treatment with endobronchial valves (EBV) aiming at total lobar occlusion is beneficial. The aim of this study was to assess the results after staged bilateral endoscopic treatment with EBV. This is a retrospective analysis of patients with severe airflow obstruction, who were treated bilaterally with EBV in two stages, aiming at subsequent atelectasis. Pre- and postintervention lung function parameters, the 6-minute walk test (6-MWT), complications, and follow-up were recorded. Sixteen patients were treated bilaterally in two stages. There was an overall improvement in lung function from baseline to second-treatment follow-up with an increase in FEV1 (23.57-29.21% of predicted) and a decrease in residual volume (299.21-240.10% of predicted) and total lung capacity (140.78-128.71% of predicted). The 6-MWT improved up to 54 m. After each procedure, 9 of 16 patients (56.25%) developed an atelectasis of the target lobe. Overall, pneumothorax occurred in 8 of 32 procedures (25%). No patient died. Patients benefitted from the first EBV treatment. The second treatment did not lead to marked improvements compared to the first treatment. Bilateral lung volume reduction with valves is possible; however, the current results seem not to justify bilateral valve treatment as a routine approach.

Lobar Collapse Therapy Using Endobronchial Valves as a New Complementary Approach to Treat Cavities in Multidrug-Resistant Tuberculosis and Difficult-to-Treat Tuberculosis: A Case Series.

BACKGROUND: The poor treatment outcomes of multidrug-resistant tuberculosis (TB) and the emergence of extensively drug-resistant TB and extremely and totally drug-resistant TB highlight the urgent need for new antituberculous drugs and other adjuvant treatment approaches. OBJECTIVES: We have treated cavitary tuberculosis by the application of endobronchial one-way valves (Zephyr®; Pulmonx Inc., Redwood City, Calif., USA) to induce lobar volume reduction as an adjunct to drug treatment. This report describes the feasibility, effectiveness and safety of the procedure. METHODS: Patients with severe lung destruction, one or more cavities or those who were ineligible for surgical resection and showed an unsatisfactory response to standard drug treatments were enrolled. During bronchoscopy, endobronchial valves were implanted in the lobar or segmental bronchi in order to induce atelectasis and reduce the cavity size. RESULTS: Four TB patients and 1 patient with atypical mycobacteriosis were treated. The mean patient age was 52.6 years. Complete cavity collapses were observed on CT scans in 4 of the 5 cases. All patients showed improvements in their clinical status, and sputum smears became negative within 3-5 months. There were no severe short- or long-term complications. The valves were removed in 3 of the 5 patients after 8 months on average; there was no relapse after 15 months of follow-up. CONCLUSION: These data suggest that endobronchial valves are likely to be useful adjuncts to the treatment of therapeutically difficult patients. More data are required to confirm our findings.

Computed Tomography-guided Radiofrequency Ablation for Sub-diaphragm Hepatocellular Carcinoma: Safety and Efficacy of Inducing an Artificial Pneumothorax.

We retrospectively evaluated the safety and efficacy of artificial pneumothorax induction to perform computed tomography (CT)-guided radiofrequency ablation (RFA) for sub-diaphragm hepatocellular carcinomas (HCCs). From June 2008 to October 2010 at our institution, 19 HCCs (16 patients) were treated using CT-guided RFA after artificial pneumothorax induction. A 23-G needle was inserted into the liver surface at a site of 2 connected pleurae without lung tissue. After a small amount of air was injected, the pleural space widened, creating a small pneumothorax. Additional air was insufflated via a newly inserted 18-G cannula to raise the lung away from the planned puncture line for RFA. The electrode was then advanced transthoracically. Ablation was performed using a cool-tip electrode with manual impedance control mode. The injected air was then aspirated as much as possible. Artificial pneumothorax was successfully induced in all cases. The average total volume of injected air in each case was 238ml. No artificial pneumothorax-related complication occurred; lung injury occurred in one case during RF electrode insertion. No local progression occurred during follow-up. Recurring HCCs were observed in eight patients. Artificial pneumothorax induction is safe and effective for CT-guided RFA of sub-diaphragm HCCs, which are difficult to locate on US.

An alternative method to achieve one-lung ventilation by surgical pneumothorax in difficult lung isolation patient: a case report.

It is challenging to establish one-lung ventilation in difficult airway patients. Surgical pneumothorax under spontaneous breathing to obtain well-collapsed lung is a feasible method for thoracic surgery. A 76-year-old man with right empyema was scheduled for decortication. The patient had limited mouth opening due to facial cellulitis extending from the left cheek to neck. Generally, lung isolation is achieved by double-lumen endotracheal tube or bronchial blocker. Double-lumen tube insertion is difficult for patients with limited mouth opening and right-side placement of bronchial blocker usually causes insufficient deflation. We introduce an alternative lung isolation technique by surgical pneumothorax under spontaneous breathing simply with an endotracheal tube placement. This technique has never been applied into the management of difficult one-lung ventilation. By this method, we provide an ideal surgical condition with safer, less time-consuming, and less skill-demanding anesthesia. It would be an alternative choice for management of one-lung ventilation in the difficult lung isolation patient.

Effects of combining transarterial chemoembolization with percutaneous microwave coagulation therapy for hepatocellular carcinoma abutting the diaphragm.

OBJECTIVE: This study aims to explore the clinical effectiveness of a combination therapy of transarterial chemoembolization (TACE) and percutaneous microwave coagulation therapy (PMCT) in treating hepatocellular carcinoma (HCC) abutting the diaphragm. MATERIAL AND METHODS: Six cases with HCC were treated with TACE followed by PMCT one month later with the aid of artificial pneumothorax. RESULTS: CT/MRI revealed complete necrosis in the tumor lesions and the treated tumor margins (≥ 5 mm). Serum alpha-fetoprotein (AFP) levels markedly declined in patients who originally had higher serum AFP levels. Postoperative complications such as fever, mild hepatic dysfunction and pleural effusion were alleviated within a short period of time. All patients were closely monitored through follow-up; all patients survived, except for one patient who received a liver transplantation. CONCLUSIONS: As lesions are either invisible or poorly visible in sonography, determining an effective treatment for HCC abutting the diaphragm remains a particular challenge. TACE and PMCT combined therapy with the aid of artificial pneumothorax proved to be an available treatment option.

[DIFFERENTIATED TACTICS OF VIDEOTHORACOSCOPIC DIAGNOSIS OF THE PLEURAL EXUDATE SYNDROME].

Differentiated tactics of diagnostic videothoracoscopy (VTHS) in a pleural exudate syndrome, which ought to be treated with hydrothorax elimination and artificial pneumothorax creation, was proposed. Further roentgenological investigation permits to create a plan for the operation conduction and a certain anesthesia application. Criteria for the operation planning and the anesthesiological support choice were elaborated. Results of VTHS conduction in 261 patients in Department of Thoracic Surgery were analyzed. The differentiated tactics for the VTHS performance application have had saved the patients from the unnecessary endotracheal narcosis conduction, and reduced a pharmacological load on a patient, as well as a rate of contraindications for the operation usage and the stationary treatment duration.

Ultrasound-guided pneumothorax induction prior to local anaesthetic thoracoscopy.

Local anaesthetic thoracoscopy (LAT) is performed by a growing number of respiratory physicians in the context of an expanding population with pleural disease. Most LATs occur in patients with moderate to large effusions where the presence of fluid allows safe access to the pleural space. Patients with little or no fluid, but other features concerning for pleural disease, are usually investigated by surgical means. Advanced LAT practitioners can also provide this service through pneumothorax induction, although there is little published data on the safety or efficacy of this technique. We present data from a series of 77 consecutive patients in whom ultrasound-guided pneumothorax induction and LAT were attempted. 67 procedures (87.0%) were successful, with the most common histopathological diagnoses being chronic pleuritis (58.2%) and mesothelioma (16.4%). No adverse events were reported secondary to the procedure. These findings demonstrate the utility of this approach and should inform future practice and guidelines.

The effects of cardiopulmonary bypass on pulmonary function during robotic cardiac surgery.

BACKGROUND: We aimed to investigate the effects of cardiopulmonary bypass (CPB) on pulmonary function under the conditions of one-lung ventilation (OLV) and carbon dioxide pneumothorax in robotic cardiac surgery. METHODS: Ninety-eight patients underwent robotic cardiac surgery using the da Vinci Surgical System, including 58 on-pump surgeries and 40 off-pump surgeries. Respiratory parameters and arterial blood gases were assessed at the following time points: 25 min after the induction of anesthesia under two-lung ventilation (T1), 25 min after OLV (T2), 25 min after the termination of CPB under OLV in the on-pump group or 25 min after the main surgery intervention in the off-pump group (T3) and 20 min before the end of surgery (T4). Dynamic lung compliance (Cdyn), alveolar-arterial PO2 difference (PA-aDO2), oxygenation index (OI) and artery-alveolar O2 pressure ratio (a/A) were calculated. RESULTS: No significant differences in pulmonary function parameters between T2 and T3 were observed in the off-pump group. However, in the on-pump group, compared with those at T2, PETCO2, Ppeak, PaCO2 and PA-aDO2 at T3 were higher, whereas SpO2, Cdyn, PaO2, OI and a/A were lower (p<0.05). Comparisons between the two groups at T3 indicated that SpO2, Cdyn, PaO2, OI and a/A were higher, while Ppeak, PaCO2 and PA-aDO2 were lower in the off-pump group (p<0.01). CONCLUSIONS: In robotic cardiac surgery under the conditions of OLV and carbon dioxide pneumothorax, CPB worsened pulmonary function and tolerance to OLV and carbon dioxide pneumothorax.

[Optimization of intraoperative conditions in endoscopic biopsy of intrathoracic lymph nodes].

Conducted a retrospective analysis of the results transpleural (videothoracoscopic and videoassisted) biopsy of intrathoracic lymph nodes (ITLN) performed in 91 patients with hilar lymphadenopathy syndrome of various etiologiy for the period from 2003 to 2014. Endoscopic ITLN biopsy performed in the mediastinum in the high risk zone, so patients need to create adequate and safe intraoperative comfort, in particular, the position of lying on side, imposing artificial pneumothorax before surgery, one-lung ventilation, lifting the head end of the operating table at 300. These measures provide optimal con- ditions for handling and minimizing the frequency of intraoperative complications or prevention after surgery.

Robot-assisted thoracoscopic hybrid esophagectomy in the semi-prone position under pneumothorax.

We performed robot-assisted thoracoscopic hybrid esophagectomy using the da Vinci Surgical System and demonstrated the potential benefit of this minimally invasive lymphadenectomy. Between April 2010 and October 2011, four patients with intrathoracic esophageal cancer underwent hybrid esophagectomy in the semi-prone position using a 3-arm standard da Vinci and a conventional thoracoscopic maneuver. All thoracoscopic procedures were completed using a robot-assisted technique. Robot-assisted thoracoscopic esophagectomy in the semi-prone position is safe and technically feasible. A hybrid procedure that combined standard da Vinci with conventional thoracosopic maneuvers overcomes the difficulties associated with using a standard da Vinci.

Single-lung ventilation with carbon dioxide hemipneumothorax: hemodynamic and respiratory effects in piglets.

OBJECTIVES: Video-assisted thoracoscopic surgery (VATS) has become a standard procedure in pediatric surgery. To facilitate surgical access, the dependent lung has to collapse using intrathoracic carbon dioxide insufflation and/or single-lung ventilation. These procedures can induce hemodynamic deteriorations in adults. The potential impacts of single-lung ventilation in combination with capnothorax on hemodynamics in infants have never been studied before. AIM: We conducted a randomized experimental study focusing on hemodynamic and respiratory changes during single-lung ventilation with or without capnothorax in a pediatric animal model. METHODS: Twelve piglets were randomly assigned to receive single-lung ventilation with (SLV-CO(2) ) or without (SLV) capnothorax with an insufflation pressure of 5 mmHg for a period of two hours. Before, during, and after single-lung ventilation, hemodynamic and respiratory parameters were measured. RESULTS: Although mean arterial pressure remained stable during the course of the study and no critical incidents were monitored, cardiac index (CI) decreased significantly with SLV-CO(2) (baseline 3.6 ± 1.6 l · min(-1) · m(-2) vs 2.9 ± 1.1 l · min(-1) · m(-2) at 120 min, P < 0.05). Furthermore, global end-diastolic volume and intrathoracic blood volume (ITBV) decreased as well significantly with SLV-CO(2) , causing a significant between-group difference in ITBV (P < 0.05). CONCLUSIONS: Despite a decrease in CI and preload parameters, the combination of single-lung ventilation and low-pressure capnothorax was well tolerated in piglets and could justify further clinical studies to be performed in infants and children focusing on hemodynamic and respiratory changes during VATS.

[Two cases of diaphragmatic surgery in children under artificial pneumothorax].

We reported two cases of thoracoscopic diaphragm repair in children. The first case was a 6-day old neonate undergoing thoracoscopic repair of congenital diaphragmatic hernia under general anesthesia. During operation, CO2 was insufflated with a pressure of 4 cmH2O into the thoracic cavity. Although end-tidal CO2 increased to 90 mmHg, Sp(O2) and blood pressure were maintained within normal ranges. The second case was a 20-month-old infant undergoing thoracoscopic repair of diaphragmatic laxity. During operation, end-tidal CO2 increased to around 50 mmHg. Sp(O2) and blood pressure were normal. But during the procedure, insufflation pressure increased up to 10 cmH2O accidentally and arterial blood pressure curve disappeared. Insufflation pressure was corrected quickly and the arterial blood pressure recovered to normal within 10 seconds. The physiological changes of CO2 insufflation in thoracic cavity is similar to tension pneumothorax and we must take care to keep insufflation pressure under 4 cmH2O.

Changes in respiratory mechanics of artificial pneumothorax two-lung ventilation in video-assisted thoracoscopic esophagectomy in prone position.

We aimed to clarify the changes in respiratory mechanics and factors associated with them in artificial pneumothorax two-lung ventilation in video-assisted thoracoscopic esophagectomy in the prone position (PP-VATS-E) for esophageal cancer. Data of patients with esophageal cancer, who underwent PP-VATs-E were retrospectively analyzed. Our primary outcome was the change in the respiratory mechanics after intubation (T1), in the prone position (T2), after initiation of the artificial pneumothorax two-lung ventilation (T3), at 1 and 2 h (T4 and T5), in the supine position (T6), and after laparoscopy (T7). The secondary outcome was identifying factors affecting the change in dynamic lung compliance (Cdyn). Sixty-seven patients were included. Cdyn values were significantly lower at T3, T4, and T5 than at T1 (p < 0.001). End-expiratory flow was significantly higher at T4 and T5 than at T1 (p < 0.05). Body mass index and preoperative FEV1.0% were found to significantly influence Cdyn reduction during artificial pneumothorax and two-lung ventilation (OR [95% CI]: 1.29 [1.03-2.24] and 0.20 (0.05-0.44); p = 0.010 and p = 0.034, respectively]. Changes in driving pressure were nonsignificant, and hypoxemia requiring treatment was not noted. This study suggests that in PP-VATs-E, artificial pneumothorax two-lung ventilation is safer for the management of anesthesia than conventional one-lung ventilation (UMIN Registry: 000042174).

CO2 artificial pneumothorax on coagulation and fibrinolysis during thoracoscopic esophagectomy.

BACKGROUND: CO2 artificial pneumothorax creates a sufficient operative field for thoracoscopic esophagectomy. However, it has potential complications and continuous CO2 insufflation may impede coagulation and fibrinolysis. We sought to compare the effects of CO2 artificial pneumothorax on perioperative coagulation and fibrinolysis during thoracoscopic esophagectomy. METHODS: We investigated patients who underwent thoracoscopic esophagectomy with (group P, n = 24) or without CO2 artificial pneumothorax (group N, n = 24). The following parameters of coagulation-fibrinolysis function: intraoperative bleeding volume; serum levels of tissue plasminogen activator (t-PA), plasminogen activator inhibitor (PAI-1), thromboelastogram (TEG), D-Dimer; and arterial blood gas levels were compared with two groups. RESULTS: Group P showed higher levels of PaCO2, reaction time (R) value and kinetics (K) value, but significantly lower pH value, alpha (α) angle and Maximum Amplitude (MA) value at 60 minutes after the initiation of CO2 artificial pneumothorax than group N ((P < .05, all). The t-PA level after CO2 insufflation for 60 minutes was significantly higher in group P than in group N (P < .05), but preoperative levels were gradually restored on cessation of CO2 insufflation for 30 min (P > .05). There was no significant difference in D-dimer. CONCLUSION: CO2 artificial pneumothorax during thoracoscopic esophagectomy had a substantial impact on coagulation and fibrinolysis, inducing significant derangements in pH and PaCO2. TRIAL REGISTRATION: The study was registered at the Chinese clinical trial registry (ChiCTR1800019004).