Bilateral Lung Ventilation Research Articles

489. EVALUATION OF THE ONCOLOGICAL QUALITY OF MINIMALLY INVASIVE TRANSCERVICAL OESOPHAGECTOMY (MICE) USING A CADAVERIC MODEL

Abstract Background Nodal involvement is a well-known factor of poor prognosis for esophageal cancer, but the extent of the lymph node dissection, or the number of the dissected lymph nodes, remains controversial questions. Western guidelines (ESMO and NCCN) suggest accomplishing esophagectomy with en-bloc two-field lymphadenectomy. Minimally Invasive transCervical oEsophagectomy (MICE) is a novel technique for the minimally invasive treatment of esophageal cancer. In the literature, the radicality of this procedure still remains unknown, as evidenced by studies conducted in Eastern countries. This descriptive study explores feasibility of MICE in Western countries using a cadaveric model. Methods A cadaver study was conducted in a real operating room setting, with bilateral lung ventilation induced to replicate a real-life situation. Mediastinal dissection was carried out via single port left transcervical mediastinoscopy. Subsequently, a right thoracoscopy in prone position was performed to access the clearance of the fatty tissue at the anatomical boundaries of the lymph node stations. The finalization of the dissection of the lower mediastinum via transhiatal approach was not performed because it was not in the aim of the study. The extent and the radicality of the dissection were evaluated by an independent external expert. Results Results indicated effectiveness of MICE in dissecting lymph nodes around the lower and middle esophagus, as well as at the subcarinal station. At the upper esophagus level, harvesting was complete on the left side but some residual tissue was found on the right-side at the right recurrent laryngeal nerve and on the right pleura, this result was attributed to technical difficulty. Conclusion The findings suggest that MICE is adequate in accomplish a complete dissection of lymph nodes around the mediastinal esophagus, including a complete subcarinal dissection, adhering to Western lymphadenectomy standards. Further descriptive study on cadaver will help to understand if a more extensive lymphadenectomy is achievable.

Single-Lung Ventilation in Infants for Surgical Repair of Coarctation of The Aorta Without Cardiopulmonary Bypass.

To investigate the effect of improving the operative field and postoperative atelectasis of single-lung ventilation (SLV) in the surgical repair of coarctation of the aorta (CoA) in infants without the use of cardiopulmonary bypass (CPB). This was a retrospective cohort study. The clinical data of 28 infants (aged 1 to 4 months, weighing between 4.2 and 6 kg) who underwent surgical repair of CoA without CPB from January 2019 to May 2022 were analyzed. Fourteen infants received SLV with a bronchial blocker (Group S), and the other 14 infants received routine endotracheal intubation and bilateral lung ventilation (Group R). In comparison to Group R, Group S exhibited improved exposure of the operative field, a lower postoperative atelectasis score (P<0.001), reduced prevalence of hypoxemia (P=0.01), and shorter durations of operation, mechanical ventilation, and ICU stay (P=0.01, P<0.001, P=0.03). There was no difference in preoperative information or perioperative respiratory and circulatory indicators before SLV, 10 minutes after SLV, and 10 minutes after the end of SLV between the two groups (P>0.05). Intraoperative bleeding, intraoperative positive end-expiratory pressure (PEEP), and systolic pressure gradient across the coarctation after operation were also not different between the two groups (P>0.05). This study demonstrates that employing SLV with a bronchial blocker is consistent with enhanced operative field, reduced operation duration, lower prevalence of intraoperative hypoxemia, and fewer postoperative complications during the surgical repair of CoA in infants without the use of CPB.

Dual Image Navigation to Secure Surgical Margins in Thoracoscopic Segmentectomy.

Video-assisted thoracoscopic surgery (VATS) segmentectomy is being increasingly used for the management of non-small cell lung cancer. For non-palpable lesions, surgeons frequently find difficulty in ensuring a sufficient surgical resection margin. The purpose of this study was to evaluate the role of intraoperative dual image navigation in combination with the infrared thoracoscopy with intravenous injection of indocyanine green (IRT-ICG) method and intraoperative computed tomography (CT) in detecting oncological margins. This study involved 34 consecutive patients who underwent both IRT-ICG and intraoperative CT-assisted thoracoscopic segmentectomy between October 2017 and July 2021. The intersegmental line on the visceral pleura was visualized using the IRT-ICG method. The intersegmental line was marked by clipping, and an intraoperative CT scan was performed under bilateral lung ventilation. Intraoperative CT or three-dimensional CT reconstruction images were used by surgeons to confirm the correct anatomic segmental border and to secure a sufficient resection margin. A well-defined intersegmental line was observed in 91.2% of patients. In eight cases, the surgeon needed to make some modifications to the resection line to secure a sufficient surgical margin. The mean surgical margin assessed on gross examination by the pathologist was 23.4±9.0 mm. Complete resection was achieved in all patients using this approach. Intraoperative dual image navigation combined with the IRT-ICG method and intraoperative CT scan enables surgeons to perform definitive VATS segmentectomy for non-palpable lesions.

66 SHORT-TERM RESULTS OF RADICAL SURGERY FOR ESOPHAGEAL CANCER WITHOUT THORACOTOMY

Abstract In recent years, surgery without thoracotomy for esophageal cancer has been reported by performing mediastinoscope and laparoscope-assisted esophagectomy. It is reported that this procedure reduces pulmonary complications. Methods Since June 2018, we introduced this surgical operation for esophageal cancer patients using mediastinoscope without thoracotomy. The patient was placed in a supine position and tilts head slightly to the right with bilateral lung ventilation. The upper mediastinal dissection, using a left cervical approach, was performed with a single-port mediastinoscopic technique using LigaSure™ Maryland. But the lymph nodes along the right recurrent laryngeal nerve (RLN) were dissected under direct vision using a right cervical approach. And then, the operation and the course after the operation were examined. Results We experienced 14 cases of surgery by February 2020 and have experienced only one pulmonary complication in the course of the surgery. This case had a left recurrent nerve palsy as a complication after surgery. For this reason, aspiration was combined, but it improved immediately. There were 2 patients that lung cancer and COLD (Chronic Obstructive Pulmonary Disease), but pneumonia did not occur. Suture failure was very high frequent. However, this complication decreased over time. Conclusion We reported that pneumonia after esophageal cancer surgery deteriorates the prognosis. Suppression of pneumonia by this operation formula can be expected to improve the prognosis.

Airway Bleeding After Double-Lumen Tube Placement

A 78-YEAR-OLD, 45-kg, 165-cm woman, with a history of breast cancer treated with chemoradiation, and esophageal diverticulum, presented for robotic-assisted diverticulectomy. After anesthetic induction, a 37Fr left-sided, double-lumen tube (DLT) was placed without difficulty, and placement was confirmed with fiberoptic bronchoscopy. The tracheal tissue was noted to be mottled throughout. After the patient was placed in the left lateral decubitus position, the DLT position was confirmed once again, and single-lung ventilation was initiated, with inflation of the bronchial cuff with 2.5 mL of air and clamping of the tracheal limb. After entry and insufflation of the right chest, 3-5 mL of blood were noted to be emanating from the tracheal lumen, and the surgeon noted poor lung isolation. Fiberoptic evaluation noted sanguineous secretions, which, despite lavage, failed to identify an obvious cause of bleeding, and slow bleeding persisted. In an attempt to improve single-lung isolation, an additional 2 mL of air were added to the bronchial cuff. After addition of air to the bronchial cuff, bleeding ceased and no additional significant issues occurred during the rest of the surgical procedure. After completion of the surgery, bilateral lung ventilation was reinstated and the authors repositioned the patient supine. Given the lack of obvious bleeding source and the mottled appearance of the tracheal tissue, bronchoscopy was performed for pulmonary toilet and further evaluation. The DLT was exchanged for an 8.5-mm endotracheal tube under direct visualization. The following findings (Fig 1, Fig 2) were noted. What is the diagnosis? Fig 2Bronchoscopic view from the left main stem showing full thickness injury in the membranous portion of the bronchus. Anterior surface of esophagus is visible through defect (yellow star). View Large Image Figure Viewer Download Hi-res image

The Comparison Between Bronchial Occlusion and Artificial Pneumothorax for Thoracoscopic Lobectomy in Infants

To compare the difference between single-lung ventilation with bronchial occlusion and double-lung ventilation with carbon dioxide artificial pneumothorax for thoracoscopic lobectomy in infants. This was a retrospective study. It was done in a teaching hospital. Between March 2017 and April 2020, a total of 72 infants underwent thoracoscopic lobectomy in the authors' hospital. Twenty-one patients received single-lung ventilation with bronchial occlusion, and 51 patients received carbon dioxide (CO2) artificial pneumothorax. The patient data included the endotracheal tube length, surgical exposure, intraoperative blood loss, and surgery duration. The mean arterial pressure (MAP), central venous pressure (CVP) and peak inspiratory pressure (Ppeak), partial pressure of oxygen in arterial blood (PaO2), and partial pressure of carbon dioxide in arterial blood (PaCO2) were measured at four points: time of bilateral lung ventilation before the thoracic surgery (T0), 10 minutes after the surgery started (T1), 30 minutes after the surgery started (T2), 60 minutes after the surgery started (T3), and 10 minutes after the surgery was over (T4). Compared to artificial pneumothorax, the bronchial occlusion group has the following advantages: the surgical exposure was better, the surgery duration was shorter, there was less intraoperative bleeding, and the duration of tracheal intubation was shorter (p < 0.05); bronchial occlusion resulted in a lower MAP but a higher CVP in infants at T1, T2, and T3 (p < 0.05) than the artificial pneumothorax group and resulted in a lower PaCO2 and higher PaO2 at T2, T3, and T4 (p < 0.05). There was no significant difference in Ppeak between the two groups (p > 0.05). Compared with CO2 artificial pneumothorax, bronchial occlusion is more favorable for thoracoscopic lobectomy in infants.

Novel universally applicable technique for performing bilateral transcervical mediastinoscopic-assisted transhiatal laparoscopic esophagectomy: a truly minimally invasive procedure

The procedure of mediastinoscopic-assisted transhiatal esophagectomy (MATE) is only performed in a few institutions, despite this being the ultimate form of minimally invasive surgery for performing esophagectomy for esophageal and esophagogastric cancer in that it entails no chest wall trauma. We have developed a novel, universally applicable, surgical procedure for performing bilateral transcervical mediastinoscopic-assisted transhiatal laparoscopic esophagectomy (BTC-MATLE) that is an improvement on standard MATE surgery for esophageal and esophagogastric cancer. The patient is placed in a supine position under general anesthesia with bilateral lung ventilation. BTC-MATLE combined with mediastinoscopic and transhiatal laparoscopic esophagectomy with total mediastinal lymph node dissection are performed synchronously. After lymph node dissection along both recurrent laryngeal nerves through bilateral cervical skin incisions, bilateral transcervical mediastinoscopic esophagectomy is performed to avoid collision outside the cervical region and ensure operability even in patients with narrow mediastimun. Laparoscopic gastric mobilization and subsequent lower esophageal mobilization meet the bilateral transcervical mediastinoscopic esophagectomy at the border of the middle and lower third of the esophagus. The gastric tube is pulled up into the cervical region via a posterior mediastinal route and anastomosed in the neck. BTC-MATLE was performed on 16 high-risk patients (Charlson Comorbidity Index ≥ 3 in 14 patients and two octogenarians with complex comorbidities). Median operation time and postoperative hospital stay were 231min and 15days, respectively. R0 resection was achieved in 15 patients (94%), and there were no in-hospital deaths. BTC-MATLE, a procedure for performing minimally invasive esophagectomy, is likely to become the applicable form of MATE surgery for esophageal and esophagogastric cancer, even in high-risk patients because it is truly minimally invasive and has excellent short-term outcomes.

Cadaveric evaluation of fluoroscopy-assisted placement of one-lung ventilation devices for video-assisted thoracoscopic surgery in dogs.

To evaluate the feasibility of fluoroscopy-assisted placement of one-lung ventilation (OLV) devices in dogs. Experimental study. Canine cadavers (n = 8) weighing between 20.2 and 37.4 kg. Thoracoscopic access with a two-port approach was established to evaluate bilateral lung ventilation patterns. Advancement of a left-sided Robertshaw double-lumen endobronchial tube (DLT) and the EZ-blocker (EZ) were evaluated under direct fluoroscopic guidance. Each dog also underwent bronchoscopy-assisted placement of an Arndt endobronchial blocker (EBB). Time to initial placement, success of creating complete OLV (after initial placement attempt and after up to two repositionings), and ease of placement score were recorded. Device position was evaluated bronchoscopically after each fluoroscopy-assisted placement attempt. Time to initial placement was significantly shorter for EZ than for DLT and EBB. The rate of successful placement after up to two repositioning attempts was 87.5%, 87.5%, and 100.0% on the right and 87.5%, 100.0%, 100.0% on the left for DLT, EZ, and EBB, respectively, and was not different between devices. Ease of placement scores were significantly higher for DLT compared with EZ and EBB on both the left and the right sides. Fluoroscopy-assisted placement of DLT and EZ appears feasible in canine cadavers. EZ-blocker placement was efficient and technically easier than DLT, but positioning must be adapted for dogs. Bronchoscopy-assisted placement of EBB remains highly successful. Fluoroscopy-assisted placement of EZ and DLT is a useful alternative to bronchoscopy-assisted placement of these OLV devices.

P2.16-41 Intraoperative Computed Tomography After Tumor Marking with Metal Clips for Non-Palpable Lung Tumors

Locating small, non-palpable lung tumors during video-assisted thoracoscopic surgery (VATS) is difficult. We report a simple method to identify such tumors during VATS, using intraoperative computed tomography (IO-CT). From 2015 to 2017, we performed IO-CT scans for patients who preoperatively seemed to have non-palpable lung tumors. We initially tried to locate these tumors by finger palpation through the thoracoscopic ports. IO-CT scans were performed after marking tumors with metal clips. For difficult-to-palpate tumors, tumor marking was based on the anatomical position as follows. First, we estimated the intercostal muscle that could best be used as a marker from preoperative CT. A needle was inserted along the caudal side of the intercostal muscle to make a slight “pin-point” depression in the parietal pleura. Next, under bilateral lung ventilation, the surface of the visceral pleura touching the parietal pleural needle depression was marked by a modern electrosurgical unit in SOFT COAG mode. Under unilateral lung ventilation again, metal clips were used to indicate the SOFT COAG marking. Intraoperative CT scans under bilateral lung ventilation and 3D-CT imaging allowed us to locate the tumor by reference to the clips. We performed wedge resections during VATS, based on the marking clips, using surgical staplers. We employed this procedure for a total of 20 tumors in 17 patients, whose mean age was 63.5 years (range: 34–78 years). Of the 20 tumors, 11 were in the right lung and 9 in the left lung; 8 were non-palpable and 12 were palpable; in preoperative CT, 7 were seen as pure ground-glass nodule (GGN) type, 2 were part-solid type, and 11 were pure solid type; pathologically, 10 were primary lung cancers, 7 were metastatic lung cancers and 3 were benign tumors. Mean tumor size was 7.1 mm and mean distance from the pleura was 7.2 mm. All tumors were identified intraoperatively by using IO-CT scans. All tumors were completely resected during VATS, with no intra-postoperative complications. IO-CT scans after tumor marking with metal clips during VATS can accurately locate non-palpable small sized lung tumors.

Safety Assessment for Thoracoscopic Day Case Surgery in Children with Congenital Pulmonary Malformation

No data exist evaluating the utilization and safety of outpatient thoracoscopy in children. The aim of this study was to investigate the safety of outpatient thoracoscopy and to assess parental opinions on the advantages and disadvantages of a pediatric thoracoscopy outpatient setting. A retrospective review of data from patients treated by thoracoscopy for congenital pulmonary malformation between 2013 and 2016 was performed. Study focused on patients who underwent outpatient thoracoscopy. All were placed in a flank position and underwent a three-port (5-mm optical trocar and two 5-mm trocars) thoracoscopy. Insufflation pressure required was 5 mmHg with bilateral lung ventilation. Pain control was provided with multimodal postoperative analgesia and the use of paravertebral block for regional analgesia. No drain was inserted. Outcomes of interest included 30-day overall morbidity, readmission, reoperation, and parental opinions through a phone call questionnaire. A total of 37 thoracoscopies were identified; 11 (30%) with a median age of 5.3 months (4.2-12.3) were performed as an outpatient procedure (10 sequestration, 1 bronchogenic cyst). Median operating time was 51 minutes (34-87). No conversion and no transfusion occurred. No complications occurred (no morbidity, no readmission, and no reoperation). According to parents' view the outpatient setting has no disadvantages. This first analysis of a small monocentric dataset demonstrates that pediatric patients can safely undergo thoracoscopy, an outpatient procedure, with a high rate of parental satisfaction.

Physiologic Evaluation of Ventilation Perfusion Mismatch and Respiratory Mechanics at Different Positive End-expiratory Pressure in Patients Undergoing Protective One-lung Ventilation.

Arterial oxygenation is often impaired during one-lung ventilation, due to both pulmonary shunt and atelectasis. The use of low tidal volume (VT) (5 ml/kg predicted body weight) in the context of a lung-protective approach exacerbates atelectasis. This study sought to determine the combined physiologic effects of positive end-expiratory pressure and low VT during one-lung ventilation. Data from 41 patients studied during general anesthesia for thoracic surgery were collected and analyzed. Shunt fraction, high V/Q and respiratory mechanics were measured at positive end-expiratory pressure 0 cm H2O during bilateral lung ventilation and one-lung ventilation and, subsequently, during one-lung ventilation at 5 or 10 cm H2O of positive end-expiratory pressure. Shunt fraction and high V/Q were measured using variation of inspired oxygen fraction and measurement of respiratory gas concentration and arterial blood gas. The level of positive end-expiratory pressure was applied in random order and maintained for 15 min before measurements. During one-lung ventilation, increasing positive end-expiratory pressure from 0 cm H2O to 5 cm H2O and 10 cm H2O resulted in a shunt fraction decrease of 5% (0 to 11) and 11% (5 to 16), respectively (P < 0.001). The PaO2/FIO2 ratio increased significantly only at a positive end-expiratory pressure of 10 cm H2O (P < 0.001). Driving pressure decreased from 16 ± 3 cm H2O at a positive end-expiratory pressure of 0 cm H2O to 12 ± 3 cm H2O at a positive end-expiratory pressure of 10 cm H2O (P < 0.001). The high V/Q ratio did not change. During low VT one-lung ventilation, high positive end-expiratory pressure levels improve pulmonary function without increasing high V/Q and reduce driving pressure.

Intraoperative Computed Tomography Navigation During Thoracoscopic Segmentectomy for Small-sized Lung Tumors

Performance of thoracoscopic pulmonary segmentectomy for primary lung cancer or pulmonary metastases has recently increased. In patients with emphysema, identification of the intersegmental line is often difficult. For nonpalpable lesions, securing a sufficient surgical margin is more likely to be uncertain. The purpose of this study was to evaluate the efficacy of intraoperative computed tomography (CT) scan during video-assisted thoracoscopic surgery (VATS) pulmonary segmentectomy. This study included 12 patients who underwent intraoperative CT-assisted VATS segmentectomy between January 2015 and August 2016. After dividing the corresponding vessels and bronchi, the intersegmental line was marked by clipping, and intraoperative CT scan was performed under bilateral lung ventilation. The intraoperative CT or 3-dimensional CT reconstruction images were used by the surgeons to confirm the correct anatomical segmental border and to secure a sufficient resection margin. In all patients, the location of the lesions to be resected, the intersegmental border, and the surgical margins could be confirmed while performing VATS segmentectomy. Complete resection was achieved in all patients. Although the pathologic margins tended to be shorter than the surgical margins on intraoperative CT images, there was a strong correlation between these 2 variables (r = 0.963, P < 0.0001). Intraoperative CT scan during VATS segmentectomy was useful for identifying the location of nonpalpable lesions, confirming anatomical intersegmental borders and securing the resection margins. Intraoperative CT navigation could enable a more definitive VATS segmentectomy for nonpalpable lesions.

How to demarcate intersegmental plane with resected-segments inflation method using the slip knot technique in thoracoscopic anatomic segmentectomy.

Intersegmental demarcation line on the surface of the visceral pleura could not be found at thoracoscopic findings. The resected segments inflation (RSI) method has been reported as a useful technique for visualizing the intersegmental demarcation line during segmentectomy. Thoracoscopic anatomic segmentectomy is performed as follows: firstly, the pulmonary vein and artery of the segment planned for resection are dissected from the hilum in order to isolate the segmental bronchus located behind the pulmonary artery. Secondly, a monofilament non-absorbable suture is passed through the segmental bronchus, and a slip-knot is made outside the thorax. Thirdly, bilateral lung ventilation with pure oxygen is conducted. When the affected segment has inflated sufficiently, the slip knot suture is pulled and the segmental bronchus is ligated and collapse of the lung is made on reserved segments. Fourthly, as inflation of the affected segment and collapse of the reserved segments could be found, resection of intersegmental plane could be easily performed with the inflation-deflation line and the intersegmental pulmonary vein. If resected segmental bronchus could be identified, thoracoscopic segmentectomy with the slip-knot technique would be applicable. This slip-knot procedure is economical and is not need special instrument.

ED08.01 Surgery of Early-Stage NSCLC

ED08.01 Surgery of Early-Stage NSCLC

Mediastinoscope and laparoscope-assisted esophagectomy.

Mediastinoscope-assisted transhiatal esophagectomy (MATHE) is a minimally invasive option for thoracic esophageal cancer with the potential benefit of decreasing pulmonary complications by avoiding one-lung ventilation or a transthoracic procedure. However, the conventional MATHE procedure is less radical than transthoracic esophagectomy due to operative view limitations and insufficient mediastinal lymphadenectomy. In upper mediastinal dissection, the conventional MATHE procedure only provides esophageal mobilization with or without lymph node sampling. We developed a novel MATHE procedure with en bloc mediastinal lymphadenectomy by introducing a single-port laparoscopic technique. The patient was placed in a supine position with bilateral lung ventilation. The upper mediastinal dissection, using a left cervical approach, was performed with a single-port mediastinoscopic technique. A laparoscope was used as a 'mediastinoscope'. The lymph nodes along the right recurrent laryngeal nerve (RLN) were dissected under direct vision using a right cervical approach. Bilateral cervical approaches were followed by hand-assisted laparoscopic transhiatal esophagectomy. A single-port technique provides a favorable expansion of the mediastinal space by carbon dioxide insufflation, and improves the visibility and handling in the deep mediastinum around the aortic arch, allowing for en bloc lymphadenectomy in the upper mediastinum including the subaortic arch lymph nodes. In addition, a hand-assisted laparoscopic transhiatal procedure allows for en bloc lymphadenectomy in the middle and lower mediastinum including the subcarinal and bilateral main bronchial lymph nodes. Cervical and transhiatal procedures were performed safely and carefully under video-assisted magnified vision according to the standardized procedure with an appropriate operative field expansion using retractors. Single-port MATHE is feasible as a novel minimally invasive surgery for esophageal squamous cell carcinoma (ESCC) or thoracic esophageal cancer.

Laryngeal clefts

Laryngeal clefts

Accurate lymphadenectomy along the recurrent laryngeal nerve based on precise positioning during thoracoscopic–laparoscopic oesophagectomy: A retrospective cohort study

AimLymph nodes along the recurrent laryngeal nerves (RLN) are considered to be highly involved in oesophageal squamous cell carcinoma patients, and radical dissection of these lymph nodes is recommended. The present study aimed to demonstrate the value of thoracoscopic–laparoscopic oesophagectomy (TLE) in radical lymphadenectomy along the bilateral RLN.Patients and MethodsFrom November 2010 to September 2012, 51 patients underwent TLE. The procedures during the radical lymphadenectomy along the bilateral RLN were done using ultrasonic scalpel with single‐lumen endotracheal tube intubation.ResultsThe lymph nodes along the RLN could be sufficiently removed with an extremely low incidence of RLN injury. The mean number of lymph nodes removed was 3.58 ± 2.59 along the right RLN, and 2.73 ± 1.66 along the left RLN. There were two types of origin for right RLN; the origin of the majority was adjacent to the right subclavian artery, and the origin of three cases was away from the right subclavian artery.ConclusionsTLE in combination with a single‐lumen tube, bilateral lung ventilation and semiprone position could be safely and efficiently applied in radical lymphadenectomy along the bilateral RLN. Ultrasonic scalpel could be safely used in lymphadenectomy along the RLN without increased heat injury of RLN.

Pulmonary Resection

Anatomic resections of the lung (including pneumonectomy and lobectomy) are the standard operative techniques employed to treat both neoplastic and nonneoplastic diseases of the lung. Preoperative evaluation is described. Once assessment of sufficient pulmonary reserve to tolerate the procedure is made, guidance is provided for anesthesia (bilateral or unilateral lung ventilation); placement of catheters; positioning in the lateral decubitus position; and type of incision to be made (posterior lateral thoracotomy or small incisions). Special intraoperative issues are also touched upon, especially resections that begin with the finding of benign- or malignant-appearing adhesions. The operative techniques are described for a right and left hilar dissection; a right and left upper lobectomy; a right middle lobectomy; a right lower lobectomy; and a right and left pneumonectomy. For each technique described, the chapter addresses the anatomical considerations of the pulmonary veins and arteries; the fissure between the upper and lower lobes; and the bronchi. Figures indicate the various steps of the hilar dissection and upper, middle, and lower lobectomy of both the right and left lung and a left pneumonectomy. This review contains 13 figures, 5 tables, and 6 additional readings.

Setting Individualized Positive End-Expiratory Pressure Level with a Positive End-Expiratory Pressure Decrement Trial After a Recruitment Maneuver Improves Oxygenation and Lung Mechanics During One-Lung Ventilation

We investigated whether individualized positive end-expiratory pressure (PEEP) improves oxygenation, ventilation, and lung mechanics during one-lung ventilation compared with standardized PEEP. Thirty patients undergoing thoracic surgery were randomly allocated to the study or control group. Both groups received an alveolar recruitment maneuver at the beginning and end of one-lung ventilation. After the alveolar recruitment maneuver, the control group had their lungs ventilated with a 5 cm·H2O PEEP, while the study group had their lungs ventilated with an individualized PEEP level determined by a PEEP decrement trial. Arterial blood samples, lung mechanics, and volumetric capnography were recorded at multiple timepoints throughout the procedure. The individualized PEEP values in study group were higher than the standardized PEEP values (10 ± 2 vs 5 cm·H2O; P < 0.001). In both groups, arterial oxygenation decreased when bilateral-lung ventilation was switched to one-lung ventilation and increased after the alveolar recruitment maneuver. During one-lung ventilation, oxygenation was maintained in the study group but decreased in the control group. After one-lung ventilation, arterial oxygenation was significantly higher in the study group (306 vs 231 mm·Hg, P = 0.007). Static compliance decreased in both groups when bilateral-lung ventilation was switched to one-lung ventilation. Static compliance increased significantly only in the study group (P < 0.001) after the alveolar recruitment maneuver and optimal PEEP adjustment. The alveolar recruitment maneuver did not decrease cardiac index in any patient. During one-lung ventilation, the improvements in oxygenation and lung mechanics after an alveolar recruitment maneuver were better preserved by ventilation by using individualized PEEP with a PEEP decrement trial than with a standardized 5 cm·H2O of PEEP.

Higher fraction of inspired oxygen in anesthesia induction does not affect functional residual capacity reduction after intubation: a comparative study of higher and lower oxygen concentration

Low fraction of inspired oxygen (FIO2) reduces the atelectasis area during anesthesia induction. However, atelectasis may occur during laryngoscopy and endotracheal intubation because lungs can collapse within a fraction of a second. We assessed the effects of ventilation with 100 and 40% oxygen on functional residual capacity (FRC) in patients undergoing general anesthesia. Twenty patients scheduled for elective open abdominal surgery were randomized into 40% oxygen (GI, n=10) and 100% oxygen (GII, n=10) groups and FRC was measured. Preoxygenation and mask ventilation with 40 and 100% oxygen were used in GI and GII, respectively. In both groups, 40% oxygen was used for anesthesia maintenance after intubation. Bilateral lung ventilation was performed with volume guarantee and low tidal volume (7ml/kg predicted body weight) using bilevel airway pressure. We measured FRC and blood gas in all patients during preoxygenation, after intubation, and during surgery. FRC decreased from during preoxygenation (GI 2380ml, GII 2313ml) to after intubation (GI 1569ml, GII 1586ml) and significantly decreased during surgery (GI 1338ml, GII 1417ml) (P<0.05). PaO2/FIO2 decreased from during preoxygenation (GI 419mmHg, GII 427mmHg) to after intubation (GI 381mmHg, GII 351mmHg) and significantly decreased during surgery (GI 333mmHg, GII 291mmHg) (P<0.05). No significant differences were found between the groups in both parameters. FRC significantly decreased from the awake state to surgery in both groups. FRC was not influenced by FIO2 elevation at anesthesia induction.