Comparative effects of variable versus conventional volume-controlled one-lung ventilation on gas exchange and respiratory system mechanics in thoracic surgery patients: A randomized controlled clinical trial

BACKGROUND

Mechanical ventilation with variable tidal volumes (V-VCV) has the potential to improve lung function during general anesthesia. We tested the hypothesis that V-VCV compared to conventional volume-controlled ventilation (C-VCV) would improve intraoperative arterial oxygenation and respiratory system mechanics in patients undergoing thoracic surgery under one-lung ventilation (OLV).

METHODS

Patients were randomized to V-VCV (n = 39) or C-VCV (n = 39). During OLV tidal volume of 5 mL/kg predicted body weight (PBW) was used. Both groups were ventilated with a positive end-expiratory pressure (PEEP) of 5 cm H2O, inspiration to expiration ratio (I:E) of 1:1 (during OLV) and 1:2 during two-lung ventilation, the respiratory rate (RR) titrated to arterial pH, inspiratory peak-pressure ≤ 40 cm H2O and an inspiratory oxygen fraction of 1.0.

RESULTS

Seventy-five out of 78 Patients completed the trial and were analyzed (dropouts were excluded). The partial pressure of arterial oxygen (PaO2) 20 min after the start of OLV did not differ among groups (V-VCV: 25.8 ± 14.6 kPa vs C-VCV: 27.2 ± 15.3 kPa; mean difference [95% CI]: 1.3 [-8.2, 5.5], P = 0.700). Furthermore, intraoperative gas exchange, intraoperative adverse events, need for rescue maneuvers due to desaturation and hypercapnia, incidence of postoperative pulmonary and extra-pulmonary complications, and hospital free days at day 30 after surgery did not differ between groups.

CONCLUSIONS

In thoracic surgery patients under OLV, V-VCV did not improve oxygenation or respiratory system mechanics compared to C-VCV. Ethical Committee: EK 420092019.

TRIAL REGISTRATION

at the German Clinical Trials Register: DRKS00022202 (16.06.2020).

One-lung ventilation with fixed and variable tidal volumes on oxygenation and pulmonary outcomes: A randomized trial

OBJECTIVE

Test the hypothesis that one-lung ventilation with variable tidal volume improves intraoperative oxygenation and reduces postoperative pulmonary complications after lung resection.

BACKGROUND

Constant tidal volume and respiratory rate ventilation can lead to atelectasis. Animal and human ARDS studies indicate that oxygenation improves with variable tidal volumes. Since one-lung ventilation shares characteristics with ARDS, we tested the hypothesis that one-lung ventilation with variable tidal volume improves intraoperative oxygenation and reduces postoperative pulmonary complications after lung resection.

DESIGN

Randomized trial.

SETTING

Operating rooms and a post-anesthesia care unit.

PATIENTS

Adults having elective open or video-assisted thoracoscopic lung resection surgery with general anesthesia were randomly assigned to intraoperative ventilation with fixed (n = 70) or with variable (n = 70) tidal volumes.

INTERVENTIONS

Patients assigned to fixed ventilation had a tidal volume of 6 ml/kgPBW, whereas those assigned to variable ventilation had tidal volumes ranging from 6 ml/kg PBW ± 33% which varied randomly at 5-min intervals.

MEASUREMENTS

The primary outcome was intraoperative oxygenation; secondary outcomes were postoperative pulmonary complications, mortality within 90 days of surgery, heart rate, and SpO2/FiO2 ratio.

RESULTS

Data from 128 patients were analyzed with 65 assigned to fixed-tidal volume ventilation and 63 to variable-tidal volume ventilation. The time-weighted average PaO2 during one-lung ventilation was 176 (86) mmHg in patients ventilated with fixed-tidal volume and 147 (72) mmHg in the patients ventilated with variable-tidal volume, a difference that was statistically significant (p < 0.01) but less than our pre-defined clinically meaningful threshold of 50 mmHg. At least one composite complication occurred in 11 (17%) of patients ventilated with variable-tidal volume and in 17 (26%) of patients assigned to fixed-tidal volume ventilation, with a relative risk of 0.67 (95% CI 0.34-1.31, p = 0.24). Atelectasis in the ventilated lung was less common with variable-tidal volumes (4.7%) than fixed-tidal volumes (20%) in the initial three postoperative days, with a relative risk of 0.24 (95% CI 0.01-0.8, p = 0.02), but there were no significant late postoperative differences. No other secondary outcomes were both statistically significant and clinically meaningful.

CONCLUSION

One-lung ventilation with variable tidal volume does not meaningfully improve intraoperative oxygenation, and does not reduce postoperative pulmonary complications.

Association between mechanical power during one-lung ventilation and pulmonary complications after thoracoscopic lung resection surgery: a prospective observational study

BACKGROUND

The role of mechanical power on pulmonary outcomes after thoracic surgery with one-lung ventilation was unclear. We investigated the association between mechanical power and postoperative pulmonary complications in patients undergoing thoracoscopic lung resection surgery.

METHODS

In this single-center, prospective observational study, 622 patients scheduled for thoracoscopic lung resection surgery were included. Volume control mode with lung protective ventilation strategies were implemented in all participants. The primary endpoint was a composite of postoperative pulmonary complications during hospital stay. Multivariable logistic regression models were used to evaluate the association between mechanical power and outcomes.

RESULTS

The incidence of pulmonary complications after surgery during hospital stay was 24.6% (150 of 609 patients). The multivariable analysis showed that there was no link between mechanical power and postoperative pulmonary complications.

CONCLUSIONS

In patients undergoing thoracoscopic lung resection with standardized lung-protective ventilation, no association was found between mechanical power and postoperative pulmonary complications.

TRIAL REGISTRATION

Trial registration number: ChiCTR2200058528, date of registration: April 10, 2022.

Effect of a 3D-printed reconstruction automated matching system for selecting the size of a left double-lumen tube: a study protocol for a prospective randomised controlled trial

INTRODUCTION

Lung isolation is primarily accomplished using a double-lumen tube (DLT) or bronchial blocker. A precise and accurate size of the DLT is a prerequisite for ensuring its accurate placement. Three-dimensional (3D) reconstruction technology can be used to accurately reproduce tracheobronchial structures to improve the accuracy of DLT size selection. Therefore, we have developed automatic comparison software for 3D reconstruction based on CT data (3DRACS). In this study, we aimed to evaluate the efficiency of using 3DRACS to select the DLT size for endobronchial intubation in comparison with using the 'blind' DLT intubation method to determine the DLT size, which is based on height and sex.

METHODS AND ANALYSIS

This is a prospective, single-centre, double-blind randomised controlled trial. In total, 200 patients scheduled for lung resection using a left DLT will be randomly allocated to the 3D group or the control group at a 1:1 ratio. A 3DRACS will be used for the 3D group to determine the size of the DLT, while in the case of the control group, the size of the DLT will be determined according to patient height and sex. The primary outcome is the success rate of placement of the left DLT without fibreoptic bronchoscopy (FOB). The secondary outcomes include the following: successful intubation time, degree of pulmonary atrophy, grade of airway injury, oxygenation during one-lung ventilation, postoperative sore throat and hoarseness, and number of times FOB is used.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from our local ethics committee (approval number: SCCHEC-02-2022-155). Written informed consent will be obtained from all participants before randomisation, providing them with clear instructions about the purpose of the study. The results will be disseminated through peer-reviewed publications and conferences.

TRIAL REGISTRATION NUMBER

NCT06258954.

Impact of One-Lung Ventilation on Oxygenation and Ventilation Time in Thoracoscopic Heart Surgery: A Comparative Analysis with Median Thoracotomy

BACKGROUND One-lung ventilation is the separation of the lungs by mechanical methods to allow ventilation of only one lung, particularly when there is pathology in the other lung. This retrospective study from a single center aimed to compare 49 patients undergoing thoracoscopic cardiac surgery using one-lung ventilation with 48 patients undergoing thoracoscopic cardiac surgery with median thoracotomy. MATERIAL AND METHODS This single-center retrospective study analyzed patients who underwent thoracoscopic cardiac surgery based on one-lung ventilation (experimental group, n=49). Other patients undergoing a median thoracotomy cardiac operation were defined as the comparison group (n=48). The oxygenation index and the mechanical ventilation time were also recorded. RESULTS There was no significant difference in the immediate oxygenation index between the experimental group and comparison group (P>0.05). There was no significant difference for the oxygenation index between men and women in both groups (P>0.05). The cardiopulmonary bypass time significantly affected the oxygenation index (F=7.200, P=0.009). Operation methods (one-lung ventilation thoracoscopy or median thoracotomy) affected postoperative ventilator use time (F=8.337, P=0.005). Cardiopulmonary bypass time (F=16.002, P<0.001) and age (F=4.384, P=0.039) had significant effects on ventilator use time. There was no significant effect of sex (F=0.75, P=0.389) on ventilator use time. CONCLUSIONS Our results indicated that one-lung ventilation thoracoscopic cardiac surgery did not affect the immediate postoperative oxygenation index; however, cardiopulmonary bypass time did significantly affect the immediate postoperative oxygenation index. Also, one-lung ventilation thoracoscopic cardiac surgery had a shorter postoperative mechanical ventilation use time than did traditional median thoracotomy cardiac surgery.

[Effects of Rhodiola rosea injection on intrapulmonary shunt and blood IL-6 and TNF-α levels during single lung ventilation in patients undergoing radical resection of esophageal cancer]

OBJECTIVE

To explore the effects of Rhodiola rosea injection on pulmonary shunt and serum interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels during single lung ventilation in patients undergoing radical resection of esophageal cancer.

METHODS

Forty-six patients undergoing radical operation for esophageal cancer were randomized equally into control group and Rhodiola rosea injection group. In the Rhodiola group, 10 mL of Rhodiola rosea injection was added into 250 mL of normal saline or 5% glucose solution for slow intravenous infusion, and normal saline of the same volume was used in the control group after the patients entered the operation room. At T0, T1 and T3, PaO2 of the patient was recorded and 2 mL of deep venous blood was collected for determination of serum TNF-α and IL-6 levels. The incidence of postoperative atelectasis of the patients was recorded.

RESULTS

Compared with those in the control group, the patients receiving Rhodiola rosea injection had significantly higher PaO2 and Qs/Qt at T1 and T2 (P<0.05) and lower serum IL-6 and TNF-α levels at T3 (P<0.05). No significant difference in the incidence of postoperative atelectasis was observed between the two groups (P>0.05).

CONCLUSION

Rhodiola rosea injection before anesthesia induction can reduce intrapulmonary shunt during single lung ventilation, improve oxygenation, reduce serum IL-6 and TNF-α levels, and alleviate intraoperative lung injury in patients undergoing radical resection of esophageal cancer.

Laryngeal mask airway combined with bronchial blocker achieved 1-lung ventilation in a patient with bilateral vocal cord paralysis: A case report

INTRODUCTION

One-lung ventilation (OLV) is a commonly used technique to facilitate surgical visualization during thoracic surgical procedures. Double-lumen endotracheal tubes and one-lumen tracheal tube combined with bronchial blocker might lead to intubation-related laryngeal injury.

PATIENT CONCERNS

In the perioperative period, how to avoid further damage to the vocal cord while achieving OLV during operation is challenging work.

DIAGNOSIS

She was diagnosed with systemic lupus erythematosus, bilateral vocal cord paralysis, and lung tumor.

INTERVENTIONS

We used a combination of a laryngeal mask airway with bronchial blocker to avoid further damage to the vocal cord when achieving OLV.

OUTCOMES

At 1-month follow-up, she had fully recovered without obvious abnormalities.

CONCLUSION

When OLV was required for patients with bilateral vocal cord paralysis, a combination of a laryngeal mask airway with bronchial blocker was considered a better choice.

Facilitating Lung Collapse for Thoracoscopic Surgery Utilizing Endobronchial Airway Occlusion Preceded by Pleurotomy and One-minute Suspension of Two-lung Ventilation

OBJECTIVES

To assess when and whether clamping the double-lumen endobronchial tube (DLT) limb of the non-ventilated lung is more conducive to a rapid and effective lung deflation than simply allowing the open limb of the DLT to communicate with the atmosphere.

DESIGN

This was a single-center, single-blind, randomized, controlled trial.

SETTING

The trial was performed in a single institutional setting.

PARTICIPANTS

The participants were 60 patients undergoing elective video-assisted thoracoscopic surgery.

INTERVENTIONS

Patients were randomized to the open-clamp airway technique (OCAT group) or control group. Patients in the control group had one-lung ventilation initiated upon being placed in the lateral decubitus position. The OCAT group had two-lung ventilation maintained until the pleural cavity was opened with the introduction of a planned thoracoscopic access port to allow the operated lung to fall away from the chest wall. Thereafter, ventilation was suspended (temporarily ceased) for 1 minute before the DLT lumen of the isolated lung was clamped. The primary outcome of the trial was the time to complete lung collapse scored as determined from video clips taken during surgery. The secondary outcomes were (1) lung collapse score at 30 minutes after pleural incision, (2) surgeon satisfaction with surgery, and (3) intraoperative hypoxemia.

MEASUREMENTS AND MAIN RESULTS

The median time to reach complete lung collapse in the OCAT group was 10 minutes (odds ratio 10.0, 95% CI 6.3-13.7), which was much shorter than that of the control group (25 minutes [odds ratio 25.0, 95% CI 13.6-36.4]). The difference in complete lung collapse at 30 minutes between the 2 groups was significant (p < 0.001). The surgeon's satisfaction with surgery was higher in the OCAT group than in the control group (8.5 ± 0.2 vs 6.8 ± 0.2; p < 0.001). There was no difference regarding intraoperative hypoxemia.

CONCLUSIONS

Suspending ventilation of both DLT limbs for 1 minute after pleural cavity opening and then clamping the DLT lumen of the isolated lung resulted in a more rapid deflation of the surgical lung. This open-clamp airway technique is an effective technique for rapid surgical lung collapse during thoracoscopic surgery.

Effects of individualized positive end-expiratory pressure on intraoperative oxygenation in thoracic surgical patients: study protocol for a prospective randomized controlled trial

BACKGROUND

Intraoperative hypoxemia and postoperative pulmonary complications (PPCs) often occur in patients with one-lung ventilation (OLV), due to both pulmonary shunt and atelectasis. It has been demonstrated that individualized positive end-expiratory pressure (iPEEP) can effectively improve intraoperative oxygenation, increase lung compliance, and reduce driving pressure, thereby decreasing the risk of developing PPCs. However, its effect during OLV is still unknown. Therefore, we aim to investigate whether iPEEP ventilation during OLV is superior to 5 cmH2O PEEP in terms of intraoperative oxygenation and the occurrence of PPCs.

METHODS

This study is a prospective, randomized controlled, single-blind, single-center trial. A total of 112 patients undergoing thoracoscopic pneumonectomy surgery and OLV will be enrolled in the study. They will be randomized into two groups: the static lung compliance guided iPEEP titration group (Cst-iPEEP Group) and the constant 5 cmH2O PEEP group (PEEP 5 Group). The primary outcome will be the oxygenation index at 30 min after OLV and titration. Secondary outcomes are oxygenation index at other operative time points, PPCs, postoperative adverse events, ventilator parameters, vital signs, pH value, inflammatory factors, and economic indicators.

DISCUSSION

This trial explores the effect of iPEEP on intraoperative oxygenation during OLV and PPCs. It provides some clinical references for optimizing the lung protective ventilation strategy of OLV, improving patient prognosis, and accelerating postoperative rehabilitation.

TRIAL REGISTRATION

www.Chictr.org.cn ChiCTR2300073411 . Registered on 10 July 2023.

Hypoxemia in School-age Children Undergoing One-lung Ventilation: A Retrospective Cohort Study from the Multicenter Perioperative Outcomes Group

BACKGROUND

Risk factors for hypoxemia in school-age children undergoing one-lung ventilation remain poorly understood. The hypothesis was that certain modifiable and nonmodifiable factors may be associated with increased risk of hypoxemia in school-age children undergoing one-lung ventilation and thoracic surgery.

METHODS

The Multicenter Perioperative Outcomes Group database was queried for children 4 to 17 yr of age undergoing one-lung ventilation. Patients undergoing vascular or cardiac procedures were excluded. The original cohort was divided into two cohorts: 4 to 9 and 10 to 17 yr of age inclusive. All records were reviewed electronically for the primary outcome of hypoxemia during one-lung ventilation, which was defined as an oxygen saturation measured by pulse oximetry (Spo2) less than 90% for 3 min or longer continuously, while severe hypoxemia was defined as Spo2 less than 90% for 5 min or longer. Potential modifiable and nonmodifiable risk factors associated with these outcomes were evaluated using separate multivariable least absolute shrinkage and selection operator regression analyses for each cohort. The covariates evaluated included age, extremes of weight, American Society of Anesthesiologists Physical Status of III or higher, duration of one-lung ventilation, preoperative Spo2 less than 98%, approach to one-lung ventilation, right operative side, video-assisted thoracoscopic surgery, lower tidal volume ventilation (defined as tidal volume of 6 ml/kg or less and positive end-expiratory pressure of 4 cm H2O or greater for more than 80% of the duration of one-lung ventilation), and procedure type.

RESULTS

The prevalence of hypoxemia in the 4- to 9-yr-old cohort and the 10- to 17-yr-old cohort was 24 of 228 (10.5% [95% CI, 6.5 to 14.5%]) and 76 of 1,012 (7.5% [95% CI, 5.9 to 9.1%]), respectively. The prevalence of severe hypoxemia in both cohorts was 14 of 228 (6.1% [95% CI, 3.0 to 9.3%]) and 47 of 1,012 (4.6% [95% CI, 3.3 to 5.8%]). Initial Spo2 less than 98% was associated with hypoxemia in the 4- to 9-yr-old cohort (odds ratio, 4.20 [95% CI, 1.61 to 6.29]). Initial Spo2 less than 98% (odds ratio, 2.76 [95% CI, 1.69 to 4.48]), extremes of weight (odds ratio, 2.18 [95% CI, 1.29 to 3.61]), and right-sided cases (odds ratio, 2.33 [95% CI, 1.41 to 3.92]) were associated with an increased risk of hypoxemia in the older cohort. Increasing age (1-yr increment; odds ratio, 0.88 [95% CI, 0.80 to 0.97]) was associated with a decreased risk of hypoxemia.

CONCLUSIONS

An initial room air oxygen saturation of less than 98% was associated with an increased risk of hypoxemia in all children 4 to 17 yr of age. Extremes of weight, right-sided cases, and decreasing age were associated with an increased risk of hypoxemia in children 10 to 17 yr of age.

EDITOR’S PERSPECTIVE

One-lung Ventilation for Patients With Laryngo-tracheal Stenosis: A Case Report and Literature Review

Context

Laryngo-tracheal stenosis (LTS) is a relatively rare disease, and conventional methods have difficulty achieving one-lung ventilation (OLV) when an anatomical abnormality exists. Selecting an appropriate method for patients with LTS can ensure oxygenation, collapse the lung, and reduce damage.

Objective

The study intended to perform a comprehensive review of the literature and a systematic review to examine the characteristics and management of OLV for LTS patients.

Design

The research team performed a narrative review by searching the PubMed and China National Knowledge Infrastructure (CNKI) databases. The search used the keywords one-lung ventilation and tracheal stenosis. The team then performed a review, including the studies found in the search and the research team's own case study.

Setting

The study took place at the First Hospital of Jilin University in Changchun, Jilin, China.

Participant

The participant in the current case study was a 72-year-old, female patient with generalized tracheal narrowing.

Results

Nine participants achieved OLV through BB, with the anesthesiologist performing SLT and using extraluminal BB for six participants.

Conclusions

Several methods can successfully achieve OLV for patients with difficult airways, but the current research team found that a small, single-lumen tube (SLT) and extraluminal bronchial blocker (BB) may be a better choice for patients with tracheal stenosis.

The Year in Thoracic Anesthesia: Selected Highlights from 2022

This article reviews research highlights in the field of thoracic anesthesia. The highlights of this year included new developments in the preoperative assessment and prehabilitation of patients requiring thoracic surgery, updates on the use of devices for one-lung ventilation (OLV) in adults and children, updates on the anesthetic and postoperative management of these patients, including protective OLV ventilation, the use of opioid-sparing techniques and regional anesthesia, and outcomes using enhanced recovery after surgery, as well as the use of expanding indications for extracorporeal membrane oxygenation, specialized anesthetic techniques for airway surgery, and nonintubated video-assisted thoracic surgery.

Curious Case of Pediatric One-Lung Ventilation with Two Endotracheal Tubes: A Case Report

ABSTRACT

One-lung ventilation is indicated during thoracic surgery for visualization and exposure of surgical site. It is achieved with bronchial blockers, double-lumen endobronchial tube, single-lumen endotracheal tubes and Univent tube for infants and children. Fibreoptic bronchoscope is required for placing and confirming the correct position of these tubes. We report a perioperative management of safe conduct of one lung ventilation for a 6-year child undergoing left lower lobe lobectomy through C-MAC video laryngoscope guided two single lumen tubes in limited resource settings where paediatric-sized fibreoptic bronchoscope is unavailable.

One-lung ventilation with a bronchial blocker in thoracic patients

BACKGROUND

Lung isolation is a technique used in a multitude of surgeries to ensure single-lung ventilation with collapse of the contralateral lung, as to achieve improved access and visualization of relevant anatomical structures. Despite being accepted and having favorable outcomes, bronchial blockers (BBs) are not to this day the main device of choice among anaesthesiologists.

METHODS

In this retrospective and descriptive study, we analyzed the safety and efficacy of a BB in all types of thoracic surgeries in our centre between 2015 and 2022, excluding patients with massive hemoptysis or empyema, or who had undergone a prior pneumonectomy.

RESULTS

One hundred and thirty-four patients were intervened due to lung cancer (67.9%), respiratory disease (23.9%), and non-respiratory disease (8.2%) undergoing lung surgeries (65.7%), pleural and mediastinal surgeries (29.9%), chest wall surgeries (3.0%) and other surgeries (1.5%). In most cases, lung collapse was considered excellent (63.9%) or good (33.1%) with only 4 cases (3.0%) of poor lung collapse. More than 90% of patients did not present intraoperative or immediate postoperative complications. No statistically significant differences were found between lung collapse and the demographic, clinical or BB-related variables (p > 0.05). However, we found a significatively higher proportion of excellent lung collapses in VATS surgeries and lateral decubitus positioning, as well as a significatively less proportion of poor lung collapses (p < 0.05). Moreover, there was a significantly higher proportion of excellent lung collapses when the BB was placed in the left bronchus (p < 0.05).

CONCLUSIONS

With these results, in our experience BBs constitute an effective alternative, capable of achieving pulmonary collapse in all kinds of thoracic procedures with satisfactory safety rates due to their minimal complications.

Effects of dexmedetomidine on pulmonary function in patients receiving one-lung ventilation: a meta-analysis of randomized controlled trial

BACKGROUND

Mechanical ventilation, particularly one-lung ventilation (OLV), can cause pulmonary dysfunction. This meta-analysis assessed the effects of dexmedetomidine on the pulmonary function of patients receiving OLV.

METHODS

The Embase, PubMed, MEDLINE, Cochrane Library, ClinicalTrials.gov, and Chinese Clinical Trial Registry databases were systematically searched. The primary outcome was oxygenation index (OI). Other outcomes including the incidence of postoperative complications were assessed.

RESULTS

Fourteen randomized controlled trials involving 845 patients were included in this meta-analysis. Dexmedetomidine improved the OI at 30 (mean difference [MD]: 40.49, 95% CI [10.21, 70.78]), 60 (MD: 60.86, 95% CI [35.81, 85.92]), and 90 min (MD: 55, 95% CI [34.89, 75.11]) after OLV and after surgery (MD: 28.98, 95% CI [17.94, 40.0]) and improved lung compliance 90 min after OLV (MD: 3.62, 95% CI [1.7, 5.53]). Additionally, dexmedetomidine reduced the incidence of postoperative pulmonary complications (odds ratio: 0.44, 95% CI [0.24, 0.82]) and length of hospital stay (MD: -0.99, 95% CI [-1.25, -0.73]); decreased tumor necrosis factor-α, interleukin (IL)-6, IL-8, and malondialdehyde levels; and increased superoxide dismutase levels. However, only the results for the OI and IL-6 levels were confirmed by the sensitivity and trial sequential analyses.

CONCLUSIONS

Dexmedetomidine improves oxygenation in patients receiving OLV and may additionally decrease the incidence of postoperative pulmonary complications and shorten the length of hospital stay, which may be related to associated improvements in lung compliance, anti-inflammatory effects, and regulation of oxidative stress reactions. However, robust evidence is required to confirm these conclusions.

A Clinical Comparison of 2 Bronchial Blockers Versus Double-Lumen Tubes for One-Lung Ventilation

OBJECTIVES

To compare the quality of lung collapse, time, and number of attempts required to achieve lung isolation, and incidence of intraoperative malpositioning between the EZ blocker (EZB), Fuji Uniblocker (UB), and the left-sided double lumen tube (DLT).

DESIGN

Prospective, randomized clinical trial.

SETTING

Single tertiary-level, university-affiliated hospital.

PARTICIPANTS

Eighty-nine patients undergoing elective open thoracotomies or video-assisted thoracoscopic surgery.

INTERVENTIONS

The 89 patients were randomized to receive a DLT, UB, or EZB for one-lung ventilation.

MEASUREMENTS AND MAIN RESULTS

The quality of lung collapse at the time of pleural opening and 10 and 20 minutes thereafter were assessed by the surgeon using the Lung Collapse Score (LCS; 0 = no lung collapse to 10 = best lung collapse). The time and number of attempts required to achieve lung isolation and the number of repositions required during surgery were measured. Tracheobronchial tree measurements were performed by radiologists from preoperative computed tomography imaging. The surgeon remained blinded to the type of device used. Twenty-nine patients were randomized to the DLT group and 30 patients to each of the EZB and UB groups. The LCSs among the groups at pleural opening and 10 minutes after pleural opening were not significantly different (p = 0.34 and p = 0.08, respectively). However, at 20 minutes after the pleural opening, the LCSs were significantly different among groups (p = 0.02), with median scores being significantly lower for DLT (9 [IQR 8-9]) than for EZB (9 [IQR 9-10]; p = 0.04) and UB (9.5 [IQR 9-10]; p = 0.02). Lung isolation was achieved fastest in the DLT group (p < 0.01). The frequency of difficult placement did not significantly differ among groups, although it occurred most frequently in UB (n = 7; 23.3%). Intraoperative repositioning also occurred most often with the UB (n = 15; 50.0%). The EZB had the greatest number of cases requiring >2 repositions (n = 4, 13.3%). There were no differences between preoperative airway measurements and time to isolation or incidence of intraoperative repositioning among the groups.

CONCLUSIONS

The LCS was comparable among the 3 devices until 20 minutes after pleural opening, when better scores were obtained in the bronchial blocker groups. Lung isolation was achieved fastest with the DLT. The EZB had the highest incidence of cases requiring >2 intraoperative repositions, mostly occurring in R-sided surgery. For L-sided surgery, the EZB performed equally to the UB. This suggests that using the EZB for R-sided video-assisted thoracoscopic surgery may be suboptimal. Preoperative airway dimensions did not correlate with time to achieve isolation or incidence of intraoperative malpositioning.

Airway management for a patient with tracheobronchomegaly undergoing lobectomy: a case report

BACKGROUND

Tracheobronchomegaly (TBM) is a rare disorder mainly characterized by dilatation and malacia of the trachea and major bronchi with diverticularization. This will be a great challenge for airway management, especially in thoracic surgery requiring one-lung ventilation. Using a laryngeal mask airway and a modified double-lumen Foley catheter (DFC) as a "blocker" may achieve one-lung ventilation. This is the first report introducing this method in a patient with TBM.

CASE PRESENTATION

We present a 64-year-old man with TBM receiving left lower lobectomy. Preoperative chest computed tomography demonstrated a prominent tracheobronchial dilation and deformation with multiple diverticularization. The most commonly used double-lumen tube or bronchial blocker could not match the distorted airways. After general anesthesia induction, a 4# laryngeal mask was inserted, through which the modified DFC was positioned in the left main bronchus with the guidance of a fiberoptic bronchoscope. The DFC balloon was inflated with 10 ml air and lung isolation was achieved without any significant air leak during one-lung or two-lung ventilation. However, the collapse of the non-dependent lung was delayed and finally achieved by low-pressure artificial pneumothorax. The surgery was successful and the patient was extubated soon after the surgery.

CONCLUSIONS

Using a laryngeal mask airway with a modified double-lumen Foley catheter acted as a bronchial blocker could be an alternative method to achieve lung isolation.

Comparing the effectiveness of single-lumen high-frequency positive pressure ventilation with double-lumen endobronchial tube for the anesthesia management of endoscopic thoracic sympathetic blockade surgery

OBJECTIVES

In this trial, we aimed to compare anesthetic effectiveness of single lumen tube (SLT) for tracheal intubation with high-frequency positive pressure ventilation (HFPPV) versus classic double lumen tube (DLT) for tracheal intubation in endoscopic thoracic sympathetic blockade surgery.

DESIGN

This was a prospective randomized controlled clinical study.

SETTING

The study was single-centered and conducted in a university hospital.

PARTICIPANTS

There were 135 endoscopic thoracic sympathetic blockade patients in this study.

INTERVENTIONS

The patients were randomly allocated either to DLT (n = 67) or SLT (n = 68) groups. In SLT group, the ventilator setting was kept with frequencies that range from 1 to 1.8 Hz (60-110/min). Data regarding anesthesia duration, surgery duration, difficult intraoperative lung deflation, postoperative atelectasis, postoperative pain, postoperative pneumothorax were recorded and compared. All patients were operated by a single experienced surgeon under general anesthesia provided by the same anesthesia team.

MEASUREMENTS AND MAIN RESULTS

Both groups were age and gender matched. Among all recorded variables, only anesthesia time was found to be close to statistical significance (P = .059, favoring single lumen). All other parameters were found to be similar between groups. (P < .05).

CONCLUSION

We reported that DLT and single lumen tracheal intubation were equally effective for lung deflation during surgery, and SLT with HFPPV ventilation mode during endoscopic thoracic sympathetic blockade surgery provided the surgeon with an adequate and clean workspace with shorter onset of anesthesia. We may suggest the HFPPV technique for uncomplicated surgery groups or where sufficient conditions for DLT cannot be provided in the operating room.

Propofol Versus Remimazolam on Cognitive Function, Hemodynamics, and Oxygenation During One-Lung Ventilation in Older Patients Undergoing Pulmonary Lobectomy: A Randomized Controlled Trial

OBJECTIVES

To investigate the effects of remimazolam on postoperative cognitive function, intraoperative hemodynamics, and oxygenation in older patients undergoing lobectomy.

DESIGN

A prospective, double-blind, randomized, controlled study.

SETTING

A university hospital.

PARTICIPANTS

Eighty-four older patients with lung cancer who underwent lobectomy, aged ≥65 years.

INTERVENTIONS

Patients were divided randomly into the remimazolam (group R) and propofol (group P) groups. Group R underwent remimazolam anesthesia induction and maintenance, whereas group P underwent propofol anesthesia induction and maintenance. Cognitive function was assessed with neuropsychological tests 1 day before surgery and 7 days after surgery. The Clock Drawing Test, Verbal Fluency Test (VFT), Digit Symbol Switching Test (DSST), and Auditory Verbal Learning Test-Huashan (AVLT-H) assessed visuospatial ability, language function, attention, and memory, respectively. The systolic blood pressure (SBP), heart rate, mean arterial pressure (MAP), and cardiac index were recorded 5 minutes before induction of anesthesia (T0), 2 minutes after sedation (T1), 5 minutes after intubation with two-lung ventilation (T2), 30 minutes after one-lung ventilation (OLV) (T3), 60 minutes after OLV (T4), and at the end of surgery (T5), and the incidences of hypotension and bradycardia were recorded. The PaO2, oxygenation index (OI), and intrapulmonary shunt (Qs/Qt) were assessed at T0, T2, T3, T4, and T5. The levels of S-100β and interleukin 6 were measured by enzyme-linked immunosorbent assay at T0, T5, 24 hours after surgery (T6), and on day 7 after surgery (T7).

MEASUREMENTS AND MAIN RESULTS

The VFT, DSST, immediate recall AVLT-H, and short-delayed recall AVLT-H scores were significantly higher in group R than in group P on day 7 after surgery (p < 0.05). The SBP and MAP at T2 to T5 were significantly higher in group R than in group P, the incidence of hypotension was significantly lower in group R (9.5%) than in group P (35.7%) (p = 0.004), and remimazolam significantly reduced the dose of phenylephrine used (p < 0.05). The PaO2 and OI at T4 were significantly higher in group R than in group P, and Qs/Qt was significantly lower in group R than in group P. The levels of S-100β at T5 were significantly lower in group R than in group P (p < 0.05).

CONCLUSION

The results showed that remimazolam (versus propofol) may lessen the degree of short-term postoperative cognitive dysfunction measured by standard neuropsychological tests, better optimize intraoperative hemodynamics, and lead to improved oxygenation during OLV.

Modified technique for endobronchial blocker placement in pediatric patients undergoing thoracic surgery

BACKGROUND

One lung ventilation (OLV) in small children can be achieved using an Arndt endobronchial blocker (AEBB), but it presents challenges. OLV during thoracic procedures provides better surgical conditions and postoperative outcomes.

AIM

To report a novel technique to improve placement and repositioning of an extraluminal AEBB for OLV.

MATERIAL AND METHODS

We describe how an angled wire is successfully used for extraluminal AEBB placement in pediatric thoracic procedures.

DISCUSSION

Since 2017, we have successfully used this technic in over 50 infants and toddlers and overcome challenges of the classic OLV in this age group.

CONCLUSIONS

The described technique allows for fast, safe, and reliable OLV while maintaining the ability to reposition the AEBB.

Recommendations and considerations for speeding the collapse of the non-ventilated lung during single-lung ventilation in thoracoscopic surgery: a literature review

Video-assisted thoracoscopic thoracic surgery has the advantages of less physical damage, less postoperative pain, and a rapid recovery. Therefore, it is widely used in the clinic. The quality of nonventilated lung collapse is the key point of thoracoscopic surgery. Poor lung collapse on the operative side damages surgical exposure and prolongs the process of surgery. Therefore, it is important to achieve good lung collapse as soon as possible after opening the pleura. Over the past two decades, there have been reports of advances in research on the physiological mechanism of lung collapse and several kinds of techniques for speeding up lung collapse. This review will inform the advances of each technique, make recommendations for reasonable implementation and discuss their controversies and considerations.

Left-Sided Double-Lumen Tube vs EZ-Blocker for One-Lung Ventilation in Thoracic Surgery: A Systematic Review and Meta-Analysis

Background. The EZ-Blocker is the newest generation of bronchial blocker and offers a potential alternative to left-sided double lumen tubes for lung isolation and one-lung ventilation during thoracic surgery. Methods. Databases were searched for randomized controlled trials comparing left-sided double lumen tube to the EZ-Blocker for one-lung ventilation during thoracic surgery. The time for placement, incidence of intraoperative displacement, and surgeons' rating of lung collapse quality were designated as coprimary outcomes. The safety profiles of the two devices, including the incidence of airway trauma and post-extubation discomfort were also examined. Results. Six randomized controlled trials (495 patients) were analyzed. Compared to the EZ-Blocker, the left-sided double lumen tube was faster to place by a weighted mean difference of [95% CI] of -61.24 seconds [-102.48, -20.00] (P = .004) and was much less likely to become displaced during lung isolation with an odds ratio [95% CI] of .56 [.34, .91] (P = .02). The left-sided double lumen tube and the EZ-Blocker provided similar surgeon-rated quality of lung isolation. Although the left-sided double lumen tube caused a greater degree of post-extubation sore throat, there was a similar incidence of carinal trauma and post-extubation hoarseness compared to the EZ-Blocker. Conclusion. Our analysis suggests that the left-sided double lumen tube can be placed more quickly and is less prone to intraoperative displacement compared to the EZ-Blocker; the quality of lung collapse is similar. Thus, evidence appears to support the continued utilization of the left-sided double lumen tube for routine thoracic surgery requiring one-lung ventilation.

Choosing the correct-sized adult double-lumen tube: Quest for the holy grail

Appropriate size selection of double-lumen tubes (DLTs) for one-lung ventilation (OLV) in adults is still a humongous task. Several important factors are to be considered like patient height, gender, tracheal diameter, left main bronchial diameter, and cricoid cartilage transverse diameter. In addition to radiological assessment of the airway diameters, the manufacturing details of the particular DLT being used also play a significant role in size selection. Optimal positioning of the appropriately sized DLT is indispensable to avoid complications like airway trauma, cuff rupture, hypoxemia, and tube displacement. It is imperative to know whether the one-size-fits-all dictum holds for DLT size selection as claimed by certain studies. Further randomized studies are required for crystallizing standard protocols ascertaining the correct DLT size. This systematic review article highlights the various parameters employed for DLT size selection and explores the newer DLTs used for adult OLV.

Assessing Provider Adherence To A Lung Protective Ventilation Protocol In Patients Undergoing Thoracic Surgery Using One-Lung Ventilation

Patients undergoing one-lung ventilation (OLV) are at risk for lung injury leading to postoperative pulmonary complications (PPCs). Lung protective ventilation (LPV) challenges traditional anesthetic management by using lower tidal volumes, individualized positive end-expiratory pressure (PEEP), and recruitment maneuvers (RMs). LPV reduces driving pressure when properly applied, which reduces the incidence of PPCs. An LPV protocol was developed and implemented for this study for patients undergoing one-lung ventilation. Knowledge and confidence were measured prior to, immediately following, and 12 weeks after an educational offering and distribution of cognitive aids. Clinical data were collected 12 weeks prior to implementation, immediately after implementation, and again at 12 weeks post-implementation. There was a significant increase in provider knowledge regarding LPV (P = .015). A significant adherence to monitoring driving pressures (P < .05) was observed at 12 weeks post-implementation. There were increases in adherence to each component (tidal volume, PEEP, RM, and FiO₂) as well as overall adherence (P = .356). Implementation of the protocol resulted in increased adherence to lung protective strategies, including a statistically significant decrease (P < 0.05) in driving pressure which has been shown to reduce complications in patients having thoracic surgery with OLV.

Association between body mass index and difficult intubation with a double lumen tube: A retrospective cohort study

STUDY OBJECTIVE

Obesity, defined by the World Health Organization as body mass index (BMI) ≥ 30.0 kg/m², is associated with adverse outcomes and challenges during surgery. Difficulties during endotracheal intubation, occur in 3-8% of procedures and are among the principal causes of anesthetic-related morbidity and mortality. Endotracheal intubation can be challenging in obese patients due to an array of anatomic and physiologic factors. Double lumen tubes (DLTs), the most commonly used airway technique to facilitate anatomic isolation of the lungs for one lung ventilation. However, DLTs can be difficult to properly position and are also more likely to cause airway injuries and bleeding when compared to conventional single lumen tubes. We investigated the association between BMI and difficult tracheal DLT intubation.

DESIGN

Retrospective cohort study.

SETTING

Operating room.

PATIENTS

We analyzed electronic records of adults having cardiac and thoracic surgery requiring general anesthesia and endotracheal intubation with DLT at the Cleveland Clinic between 2008 and 2021.

MEASUREMENTS

BMI, preoperative airway abnormalities and difficult intubation, defined as more than one intubation attempt, was assessed using multivariable logistic regression.

MAIN RESULTS

Among 8641 analyzed anesthetics requiring DLT, 1459 (17%) were difficult intubations. After adjusting for confounders, each 5 kg/m² increase in BMI was associated with a marginal increase of difficult intubation, odds ratio (OR) 1.06 (95% Confidence Interval [CI]: 1.002, 1.11; P = 0.040). Difficult intubation was not associated with airway abnormalities, estimated OR 0.85 (95% CI: 0.62, 1.17; P = 0.321). There was no interaction between known airway abnormalities and BMI (P = 0.894).

CONCLUSIONS

Difficult intubations with DLT remain common, but BMI is a weak predictor thereof. For example, an increase in BMI from 20 to 40 kg/m² corresponds to an increase in average absolute risk for difficult intubation from 16 to 19%, which probably is not clinically meaningful.

Two-lung ventilation in video-assisted thoracoscopic esophagectomy in prone position: A systematic review

Esophageal cancer surgery is still carrying a high risk of morbidity and mortality. That is why some anesthesia strategies have tried to reduce those postoperative complications. In this systematic review performed in accordance with the PRISMA-S guidelines (PROSPERO (ID: CRD42022310385)), we aimed to investigate the safety and advantages of two-lung ventilation (TLV) over one-lung ventilation (OLV) in minimally invasive esophagectomy (MIE) in the prone position. Seven trials, with a total number of 1710 patients (765 patients with TLV versus 945 patients with OLV) were included. Postoperative mortality and morbidity rates were similar between TLV and OLV when realised for esophagectomy. Interestingly, we observed no difference in changes in intraoperative respiratory parameters, operative duration, thoraco-conversion rate, number of harvested lymph nodes, postoperative heart rate and respiratory rate between TLV and OLV. TLV brings better results in terms of intraoperative oxygen arterial pressure (PaO₂) during the thoracic time, postoperative oxygenation, PaO2 on inspired fraction of oxygen (FiO₂) ratio, duration of thoracic surgery, preoperative time, blood loss, temperature on postoperative day-1, and C-reactive protein dosage. Our study highlighted the safety of TLV for MIE in prone position when compared to OLV. Interestingly, we found better intra and postoperative ventilation parameters. The choice of ventilation modality did not influence clinical outcome after surgery and the quality of oncological resection. Large randomised controlled trials are needed to confirm these results.

Intraoperative surprise evidence of bronchial rent during lung surgery: a case report

Among multiple causes of tracheobronchial rent, most common is iatrogenic factor. Whenever there is surprise evidence of bronchial wall tear while doing lung surgery, tracheal tube extubation and postoperative management pose a challenge. We report a 16-year-old girl, weighing 27kg, a case of pulmonary Koch's who presented with hydropneumothorax on left side. She had a prolonged course on mechanical ventilation, was gradually weaned off and extubated in intensive care unit (ICU) with implantable cardioverter defibrillator (ICD) in-situ. However, chest X-ray continued to show loss of bronchovascular markings and high-resolution computed tomography (HRCT) thorax revealed multiple cavitatory lesions, hydropneumothorax from upper to lower lobe, ground glass opacities on left side and mediastinal shift towards right side. Hence, she was posted for left lung decortication. Decortication was done using one lung ventilation protocol with 28 Fr left sided double-lumen endobronchial tube (DLT). While checking for leaks before closure, it was noted that exhaled tidal volume was unacceptably low and a rent on left main bronchus of around 2x2 cm with scarred borders was detected. The rent was repaired with tissue patch suturing by the surgeons. After the procedure, DLT was exchanged with endotracheal tube (ETT) no 6. Patient was managed with elective ventilation post-operatively in ICU for 48 hours and extubated uneventfully. A vigilant monitoring of vital parameters and close communication with surgeons is important for detecting and managing any perioperative complication during lung surgery. Elective ventilation could play a significant role for healing a big rent in trachea-bronchial area.

Hypoxemia in Young Children Undergoing One-lung Ventilation: A Retrospective Cohort Study

BACKGROUND

One-lung ventilation in children remains a specialized practice with low case numbers even at tertiary centers, preventing an assessment of best practices. The authors hypothesized that certain case factors may be associated with a higher risk of intraprocedural hypoxemia in children undergoing thoracic surgery and one-lung ventilation.

METHODS

The Multicenter Perioperative Outcomes database and a local quality improvement database were queried for documentation of one-lung ventilation in children 2 months to 3 yr of age inclusive between 2010 and 2020. Patients undergoing vascular or other cardiac procedures were excluded. All records were reviewed electronically for the presence of hypoxemia, oxygen saturation measured by pulse oximetry (Spo2) less than 90% for 3 min or more continuously, and severe hypoxemia, Spo2 less than 90% for 5 min or more continuously during one-lung ventilation. Records were also assessed for hypercarbia, end-tidal CO2 greater than 60 mmHg for 5 min or more or a Paco2 greater than 60 on arterial blood gas. Covariates assessed for association with these outcomes included age, weight, American Society of Anesthesiologists (Schaumburg, Illinois) Physical Status 3 or greater, duration of one-lung ventilation, preoperative Spo2 less than 98%, bronchial blocker versus endobronchial intubation, left operative side, video-assisted thoracoscopic surgery, lower tidal volume ventilation (tidal volume less than or equal to 6 ml/kg plus positive end expiratory pressure greater than or equal to 4 cm H2O for more than 80% of the duration of one-lung ventilation), and type of procedure.

RESULTS

Three hundred six cases from 15 institutions were included for analysis. Hypoxemia and severe hypoxemia occurred in 81 of 306 (26%) patients and 56 of 306 (18%), respectively. Hypercarbia occurred in 153 of 306 (50%). Factors associated with lower risk of hypoxemia in multivariable analysis included left operative side (odds ratio, 0.45 [95% CI, 0.251 to 0.78]) and bronchial blocker use (odds ratio, 0.351 [95% CI, 0.177 to 0.67]). Additionally, use of a bronchial blocker was associated with a reduced risk of severe hypoxemia (odds ratio, 0.290 [95% CI, 0.125 to 0.62]).

CONCLUSIONS

Use of a bronchial blocker was associated with a lower risk of hypoxemia in young children undergoing one-lung ventilation.

EDITOR’S PERSPECTIVE

Individualized positive end-expiratory pressure (PEEP) during one-lung ventilation for prevention of postoperative pulmonary complications in patients undergoing thoracic surgery: A meta-analysis

BACKGROUND

Positive end-expiratory pressure (PEEP) is an important part of the lung protection strategies for one-lung ventilation (OLV). However, a fixed PEEP value is not suitable for all patients. Our objective was to determine the prevention of individualized PEEP on postoperative complications in patients undergoing one-lung ventilation.

METHOD

We searched the PubMed, Embase, and Cochrane and performed a meta-analysis to compare the effect of individual PEEP vs fixed PEEP during single lung ventilation on postoperative pulmonary complications. Our primary outcome was the occurrence of postoperative pulmonary complications during follow-up. Secondary outcomes included the partial pressure of arterial oxygen and oxygenation index during one-lung ventilation.

RESULT

Eight studies examining 849 patients were included in this review. The rate of postoperative pulmonary complications was reduced in the individualized PEEP group with a risk ratio of 0.52 (95% CI:0.37-0.73; P = .0001). The partial pressure of arterial oxygen during the OLV in the individualized PEEP group was higher with a mean difference 34.20 mm Hg (95% CI: 8.92-59.48; P = .0004). Similarly, the individualized PEEP group had a higher oxygenation index, MD: 49.07mmHg, (95% CI: 27.21-70.92; P < .0001).

CONCLUSIONS

Individualized PEEP setting during one-lung ventilation in patients undergoing thoracic surgery was associated with fewer postoperative pulmonary complications and better perioperative oxygenation.

Case reports of one-lung ventilation using Fuji Uniblocker bronchial blockers for infants under one-year-old in uniportal video-assisted thoracoscopic surgery

INTRODUCTION

Uniportal video-assisted thoracoscopic surgery (VATS) for various pulmonary diseases provides advantages of less postoperative pain and earlier post-operative recovery over traditional open surgery. The inherent limitation of this surgical modality in manipulation of surgical instruments renders intra-operative one-lung ventilation a requisite to increase the substantially restricted working space and thus visibility of the surgical filed.

PATIENT CONCERNS

Patient 1, an 8-month-old, 9-kg, and 70 cm-in-height male infant was diagnosed as congenital pulmonary airway malformation (CPAM) over left lower lobe.Patient 2, a 9-month-old, 8-kg and 72 cm-in-height male infant was diagnosed as CPAM over right lower lobe.Patient 3, an 8-month-old, 8-kg and 67 cm-in-height female infant was diagnosed as CPAM over left lower lobe.This facilitating one-lung ventilation yet was rarely conducted in infants under one year of age for the extremely small body size, the unavailability of dedicated tools, and therein the very tough techniques demanded.

DIAGNOSIS

Infants with congenital cystic adenomatoid malformation.

INTERVENTIONS

Here we report three infants of less than one year of age in whom one-lung ventilation was successfully achieved by intraluminal use of 5-Fr Fuji Uniblocker Bronchial Blocker devices and in turn assisted the completion of uniportal VATS for congenital cystic adenomatoid malformation in unilateral lungs.

OUTCOMES

Three infants received VATS under uniblocker smoothly. Patient 1 had two episode of balloon dislodgement and desaturation and solved by re-insertion. And he had subglottic tracheal stenosis which treatment with laser coagulation. Patient 2 had overall blood loss 80 ml. Patient 3 had one episode of desaturation after stapling the bronchus and fiberoptic bronchoscope revealed obstruction by blood and secretion which solved by suction.

CONCLUSION

In conclusion, OLV in infants undergoing uniportal VATs could be successfully achieved by Fuji 5 Fr Uniblocker bronchial blockers for as long as 4 hours, as exemplified by our three cases, and balloon poor sealing and dislodgment can be immediately solved by bronchoscope-guided re-positioning without compromising surgical proceeding or outcome.

A case of one-lung ventilation using a single-lumen tube placed under fiberoptic bronchoscopic guidance in a 4-year-old child: A case report

RATIONALE

One-lung ventilation (OLV) is essential for adequate visualization and exposure of the surgical site via a videoscopic approach. Although many instruments facilitating OLV are available, the choice is limited in pediatric patients.

PATIENT CONCERNS

A 4-year-old female (weight: 18.6 kg, height: 100 cm) was admitted via our pediatric outpatient clinic because of recurrent hemoptysis, 2 weeks in duration. She had no medical or surgical history.

DIAGNOSIS

Contrast-enhanced computed tomography (CT) revealed a 4.5-cm-diameter mass in the left, lower lung lobe. She was diagnosed with a congenital pulmonary airway malformation (CPAM).

INTERVENTIONS

She was scheduled for emergency lobectomy via video-assisted thoracoscopic surgery (VATS). To ensure successful VATS, OLV was essential. As our hospital lacked a small-diameter fiberoptic bronchoscope and a proper bronchial blocker, we decided to use single-lumen tube (SLT) with adult fiberoptic bronchoscope.

OUTCOMES

We performed successful bronchoscopic-guided OLV using a SLT. We aligned the tube to the right upper lobar bronchus and Murphy eye to prevent obstruction of the right upper lobe bronchus. At the end of surgery, the endotracheal tube lumen had been narrowed by blood clots, we decided to exchange the tracheal tube. The tube was immediately exchanged. After re-intubation, the pulse oximetry (SpO2) then gradually increased.

LESSONS

Appropriate preparation and careful management should be considered to perform OLV in pediatric patients without significant complications.

Extraluminal bronchial blocker placement using both nostrils for lung isolation in a patient with limited mouth opening: A CARE-compliant case report

RATIONALE

The establishment of lung isolation is often particularly challenging for the anesthesiologist in patients with difficult airway. Usually, orotracheal intubation with double lumen tube is the commonly used technique for achieving 1 lung anesthesia. Whereas, in patients with limited mouth opening and restricted cervical mobility, this technique becomes extremely difficult and hazardous. We report a case in which bronchial blocker placement was succeeded via both nostrils in a difficult airway due to restricted mouth opening.

PATIENT CONCERNS

A 50-year-old, non-smoking female with a painless mass in the left upper lobe. She had a 10-year history of ankylosing spondylitis and squamous cell carcinoma of the floor of the mouth after 5 operations 4 years previously.

DIAGNOSES

Left upper lobe adenocarcinoma, ankylosing spondylitis and oral squamous cell carcinoma.

INTERVENTIONS

To achieve 1 lung anesthesia, both nostrils were used for extraluminal bronchial blocker placement.

OUTCOMES

Initially, oral intubation was selected for establishing a patent airway but failed. Then switched to nasal canal for insertion, after several attempts, a conventional nasal intubation tube (internal diameter 6.0 mm) was placed via 1 nostril under topical anesthesia, with the aid of a flexible fiberoptic bronchoscope, and a bronchial blocker was advanced to the desired position via the other nostril.

LESSONS

In difficult airway with limited mouth opening and restricted cervical mobility, multidisciplinary experts participated discussion is a prerequisite for contemplating a scientific plan. Preoperative computed tomography scan and 3-dimensional computed tomography reconstruction would be helpful in detecting the narrowest part of airway conduit and determining a safe, reliable, and feasible airway program.

A Prospective, Ex Vivo Trial of Endobronchial Blockade Management Utilizing 3 Commonly Available Bronchial Blockers

BACKGROUND

Lung isolation with bronchial blockers is a well-described and accepted procedure, often described for use during the management of massive hemoptysis. Recommendations for balloon inflation are sparse, with some advocating for saline whereas other suggest air, including the manufacturers. We sought to evaluate the optimal method for balloon inflation in an ex vivo trial.

METHODS

We performed a prospective trial utilizing 3 commercially available bronchial blockers commonly described for use in lung isolation and massive hemoptysis management. We utilized the Arndt Endobronchial Blocker (Cook Medical), the Cohen Tip Deflecting Endobronchial Blocker (Cook Medical), and the Fogarty Venous Thrombectomy Catheter (Edwards LifeSciences). Balloon size and deflation assessment were tested within 3 different scenarios comparing air versus saline.Welch t test was performed to compare means between groups, and a generalized estimating equation model was utilized to compare balloon diameter over time to account for correlation among repeated measures from the same balloon.

RESULTS

All 3 endobronchial blocker systems were observed in triplicate. During free-standing balloon inflation, all 3 endobronchial systems displayed a greater degree of balloon deflation over time with air as opposed to saline (P < .001). Within a stent-based model, inflation with air of all 3 endobronchial systems, according to manufacturer recommendations, demonstrated significantly decreased time until fluid transgression occurred when compared to a saline model (P < .001). Within a stent-based model, inflation with air, according to clinical judgment, demonstrated significantly decreased time until fluid transgression in the Arndt (P = .016) and the Fogarty (P < .001) system, but not the Cohen (P = .173) system, when compared with saline.

CONCLUSIONS

The utilization of saline for balloon inflation during bronchial blockade allows for more consistent balloon inflation. The use of saline during balloon inflation appears to delay passive, spontaneous balloon deflation time when compared to air during a model of endobronchial blockade. The approach of saline inflation should be tested in humans to demonstrate the overall applicability and validity of the current findings.

Effects of bronchial blockers on one-lung ventilation in general anesthesia: A randomized controlled trail

BACKGROUND

Double-lumen bronchial tubes (DLBT) and bronchial blockers (BB) are commonly used in the anesthesia for clinical thoracic surgery. But there are few systematic clinical comparisons between them. In this study, the effects of BB and DLBT on one-lung ventilation (OLV) are studied.

METHODS

The 200 patients with thoracic tuberculosis undergoing thoracic surgery, were randomly assigned to group A (DLBT) and group B (BB). Intubation time, hemodynamic changes (mean arterial pressure [MAP], heart rate [HR]), and arterial blood gas indicators (arterial partial pressure of carbon dioxide [PaCO2], arterial partial pressure of oxygen [PaO2], airway plateau pressure [Pplat], and airway peak pressure [Ppeak]) at 4 time points were recorded. Complications such as hoarseness, pulmonary infection, pharyngalgia, and surgical success rate were also evaluated postoperatively.

RESULTS

Intubation times were shorter in group B. Both MAP and HR in group A were significantly higher 1 minute after intubation than before, but also higher than those in group B. PaO2 levels were lower in both groups during (OLV) than immediately after anesthesia and after two-lung ventilation (TLV), with PaO2 being lower after 60 minutes of OLV than after 20 minutes of OLV. Furthermore, at both points during OLV, PaO2 was lower in group A than in group B. No significant differences in PaCO2 were found between the 2 groups. Ppeak and Pplat were increased in both groups during OLV, with both being higher in group A than in group B. The incidence of postoperative hoarseness, pulmonary infection, and pharyngalgia were lower in group B. There was no significant difference in the success rate of operation between the 2 groups.

CONCLUSIONS

Compare with using DLBT, implementation of BB in general anesthesia has less impact on hemodynamics, PaO2 and airway pressures, and achieves lower incidence of postoperative complication.

Will ultrasound replace the stethoscope?: a case report on neonatal one-lung ventilation

Background and objectives

One-lung ventilation and selective intubation in neonates can be challenging due to intrinsic physiological specificities and material available. Ultrasound (US) is being increasingly used in many extents of anaesthesiology including confirmation of endotracheal tube position.

Case report

We present a case report of a neonate proposed for pulmonary lobectomy by thoracoscopy in which lung exclusion was confirmed by ultrasound.

Conclusion

US is a rapid, more sensitive and specific method than auscultation to evaluate tracheal intubation and lung exclusion.

Successful blind lung isolation with the use of a novel double-lumen endobronchial tube in a patient undergoing lung transplantation with massive pulmonary secretion: A case report

RATIONALE

Precise lung isolation technique with visual confirmation is essential for thoracic surgeries to create a safe and clear surgical field. However, in certain situations, such as when patients have massive pulmonary secretion or when the fiberoptic bronchoscopy (FOB) is not applicable, lung isolation has been performed blindly.

PATIENT CONCERN

A 52-year-old woman, whose airway was unable to visualize with FOB due to massive pulmonary secretion, was presented for bilateral sequential lung transplantation. Extracorporeal membranous oxygenation, tracheostomy, and mechanical ventilation were applied to the patient for 39 days preoperatively as a bridge for lung transplantation.

DIAGNOSIS

Patient was diagnosed with an idiopathic pulmonary fibrosis and obesity.

INTERVENTION

Initially, height-based blind positioning with a conventional double-lumen endobronchial tube (DLT) failed to ventilate the patient properly, and the confirmation of DLT positioning with FOB was impossible due to massive pulmonary secretion. Therefore, a novel DLT (ANKOR DLT) that has one more cuff, located at a point between the distal opening of the tracheal lumen and the starting point of bronchial cuff, than conventional DLT was used for the lung isolation in the patient.

OUTCOMES

After the completion of lung graft, FOB finding showed that the ANKOR DLT was optimally positioned at the tracheobronchial tree of the patient, and its depth was 2.5 cm shallower than that of the conventional tube.

LESSONS

ANKOR DLT would be a feasible choice to achieve successful blind lung isolation when the use of FOB is impossible to achieve the optimal lung isolation.

Protective ventilation with high versus low positive end-expiratory pressure during one-lung ventilation for thoracic surgery (PROTHOR): study protocol for a randomized controlled trial

BACKGROUND

Postoperative pulmonary complications (PPC) may result in longer duration of in-hospital stay and even mortality. Both thoracic surgery and intraoperative mechanical ventilation settings add considerably to the risk of PPC. It is unclear if one-lung ventilation (OLV) for thoracic surgery with a strategy of intraoperative high positive end-expiratory pressure (PEEP) and recruitment maneuvers (RM) reduces PPC, compared to low PEEP without RM.

METHODS

PROTHOR is an international, multicenter, randomized, controlled, assessor-blinded, two-arm trial initiated by investigators of the PROtective VEntilation NETwork. In total, 2378 patients will be randomly assigned to one of two different intraoperative mechanical ventilation strategies. Investigators screen patients aged 18 years or older, scheduled for open thoracic or video-assisted thoracoscopic surgery under general anesthesia requiring OLV, with a maximal body mass index of 35 kg/m2, and a planned duration of surgery of more than 60 min. Further, the expected duration of OLV shall be longer than two-lung ventilation, and lung separation is planned with a double lumen tube. Patients will be randomly assigned to PEEP of 10 cmH2O with lung RM, or PEEP of 5 cmH2O without RM. During two-lung ventilation tidal volume is set at 7 mL/kg predicted body weight and, during OLV, it will be decreased to 5 mL/kg. The occurrence of PPC will be recorded as a collapsed composite of single adverse pulmonary events and represents the primary endpoint.

DISCUSSION

PROTHOR is the first randomized controlled trial in patients undergoing thoracic surgery with OLV that is adequately powered to compare the effects of intraoperative high PEEP with RM versus low PEEP without RM on PPC. The results of the PROTHOR trial will support anesthesiologists in their decision to set intraoperative PEEP during protective ventilation for OLV in thoracic surgery.

TRIAL REGISTRATION

The trial was registered in clinicaltrials.gov ( NCT02963025 ) on 15 November 2016.

A novel method of Uniblocker placement: extraluminal technique supported by trachea length measurement: A CONSORT-compliant article

BACKGROUND

The use of bronchial blockers has been increased for one-lung ventilation; however, the placement of bronchial blockers is time consuming. The objective of this study was to compare the novel extraluminal technique of Uniblocker placement supported by trachea length measurement on computerized tomography images with conventional intraluminal Uniblocker placement method.

METHODS

Seventy adult patients undergoing left side thoracic surgery were included in the study. All the patients were randomly assigned to one of two groups: conventional intraluminal intubation group (CV-IN group, n = 35) or extraluminal CT guided group (CT-EX group, n = 35). The primary endpoints were the optimal positions of Uniblocker and the injuries of bronchi and carina. The secondary outcomes included the time of Uniblocker placement, the adequacy of lung collapse, the incidences of Uniblocker displacement, sore throat, and hoarseness postoperative.

RESULTS

In the CV-IN group, 19 of 35 Uniblockers went to the left main-stem bronchus on the initial blind insertion and 15 of 35 Uniblockers were considered as in optimal depth, whereas in the CT-EX group, 32 of 35 Uniblockers went to the left main-stem bronchus on the initial blind insertion and 31 of 35 Uniblockers were considered as in optimal depth (P < .01). The incidence of bronchi and carina injuries was obviously lower in the CT-EX group (occurred in 1 of 35 cases) than that in the CV-IN group (occurred in 8 of 35 cases) (P < .05). The time of Uniblocker placement took 145.4 s in the CV-IN group and 85.4 s in the CT-EX group (P < .01). The malpositions of Uniblocker, the degree of pulmonary collapse and the adverse events postoperative such as sore throat and hoarseness were not significantly different between the two groups (P > .05).

CONCLUSION

The novel extraluminal technique of Uniblocker placement supported by trachea length measurement on computerized tomography images was proved to be more rapid, more accurate and less complications than conventional intraluminal Uniblocker placement method.

Transthoracic radiofrequency ablation for hepatic tumor located beneath the diaphragm under one-lung ventilation: A case report

RATIONALE

Radiofrequency ablation (RFA) has become the reliable, effective, and less invasive treatment for small primary or metastatic hepatic tumors. Hepatic tumors that located immediately beneath the diaphragm are difficult to treat with percutaneous RFA due to poor visualization by percutaneous ultrasonography and the close location of the heart or lung. A transthoracic approach has been proposed to be an alternative for hepatic tumors located beneath the diaphragm that are difficult to access by conventional percutaneous or laparoscopic approaches. There has been no report regarding the anesthetic management of the transthoracic RFA for hepatic tumor.

PATIENT CONCERNS

A 69-year-old female had undergone segmentectomy due to hepatocellular carcinoma 4 years ago.

DIAGNOSES

Newly developed hepatic tumor located in the liver dome and beneath the diaphragm was diagnosed by follow-up imaging study.

INTERVENTIONS

Because the tumor could not be identified by transabdominal ultrasonography (US), transthoracic approach for RFA under one-lung ventilation was planned. General anesthesia was induced with propofol and remifentanil via target-controlled infusion system and rocuronium was administered. Orotracheal intubation with double-lumen endotracheal tube was performed and position of the tube in the trachea was confirmed by bronchoscope. The RFA electrode was introduced percutaneously into the right pleural cavity, guided by visualization through the thoracoscope and inserted into the tumor after visualizing the tumor by US. Radiofrequency waves can be successfully administered through the needle.

OUTCOMES

We performed successfully RFA of the hepatic tumor through one-lung ventilation and transthoracic approach. At 5 days postoperatively, she was discharged in a stable condition without any complication.

LESSONS

Transthoracic RFA can be successfully performed under one-lung ventilation, optimal analgesia, and vigilant monitoring.

Role of surgical manipulation in lung inflammatory response in a model of lung resection surgery

OBJECTIVES

Lung resection surgery with one-lung ventilation leads to an inflammatory response. Surgical manipulation can play a key role in this response. Sevoflurane, a commonly used volatile anaesthetic, has a proven anti-inflammatory effect. Our main goal was to evaluate the segregated effect of surgical manipulation during lung resection surgery and the protective role of sevoflurane with regard to this response.

METHODS

Fifteen pigs underwent left thoracotomy for caudal lobectomy under general anaesthesia. The animals were divided into 3 groups: control, sevoflurane and sham. The animals in the sham group underwent left thoracotomy and one-lung ventilation over 120 min, without lobectomy. The animals in the sevoflurane group received anaesthetic maintenance with sevoflurane. The animals in the sham group and the control group received propofol during the procedure. Lung biopsies were collected before the procedure (left caudal lobe) and 24 h later (right mediastinal lobe and left upper lobe). The samples were stored to measure levels of inflammatory markers (IL-1, TNF-α and ICAM-1), apoptotic mediators (BAD, BAX, BCL-2 and Caspase-3), Syndecan-1, MicroRNAs 182, 145 and lung oedema.

RESULTS

Surgical manipulation increased the expression of inflammation (IL-1, TNF-α and ICAM-1) and proapoptotic mediators (BAX, BAD and Caspase-3). It also caused degradation of endothelial glycocalyx (Syndecan-1) and pulmonary oedema. Administration of sevoflurane reduced the elevation of inflammatory markers, degradation of glycocalyx and pulmonary oedema observed in the control group.

CONCLUSIONS

Surgical manipulation of the collapsed lung could increase the expression of inflammation and proapoptotic mediators and cause tissue damage in the form of pulmonary oedema. Sevoflurane could attenuate this molecular response and pulmonary oedema.

One-lung ventilation in a patient with a large mass on the glottis: A case report

RATIONALE

One-lung ventilation (OLV) is required during most thoracic surgeries to facilitate surgical visualization by collapsing the lung. Double-lumen tubes and bronchial blockers are two commonly used devices for OLV; however, it may be difficult to place two devices in patients with narrow inlets, such as those that have tumor-induced airway stenosis.

PATIENT CONCERNS

We report the case of an adult patient with a lung tumor that was growing rapidly and hemorrhaging; thus, a thoracotomy for lung resection should have been performed as early as possible. However, a large mass on the glottis obstructed the entry of the double-lumen tube or bronchial blocker. Therefore, the operation could not be performed because of the inability to provide one-lung ventilation via the conventional intubation method.

DIAGNOSES

Computed tomography (CT) revealed a lung tumor that was growing rapidly and preoperative bronchoscopy showed a large mass on the vocal cords.

INTERVENTIONS

After anesthesia induction, a Uniblocker and a small single lumen tube were intubated and the Uniblocker was inserted extraluminally of the single lumen tube. One-lung ventilation was achieved successfully in this patient.

OUTCOMES

The surgery proceeded uneventfully for 4 hours without any complications.

LESSONS

Extraluminal use of the Uniblocker and a small single lumen tube may be recommended for patients receiving OLV and who have narrow inlets, especially under emergency situations.

Effect of one-lung ventilation on end-tidal carbon dioxide during cardiopulmonary resuscitation in a pig model of cardiac arrest

Unrecognized endobronchial intubation frequently occurs after emergency intubation. However, no study has evaluated the effect of one-lung ventilation on end-tidal carbon dioxide (ETCO₂) during cardiopulmonary resuscitation (CPR). We compared the hemodynamic parameters, blood gases, and ETCO₂ during one-lung ventilation with those during conventional two-lung ventilation in a pig model of CPR, to determine the effect of the former on ETCO₂. A randomized crossover study was conducted in 12 pigs intubated with double-lumen endobronchial tube to achieve lung separation. During CPR, the animals underwent three 5-min ventilation trials based on a randomized crossover design: left-lung, right-lung, or two-lung ventilation. Arterial blood gases were measured at the end of each ventilation trial. Ventilation was provided using the same tidal volume throughout the ventilation trials. Comparison using generalized linear mixed model revealed no significant group effects with respect to aortic pressure, coronary perfusion pressure, and carotid blood flow; however, significant group effect in terms of ETCO₂ was found (P < 0.001). In the post hoc analyses, ETCO₂ was lower during the right-lung ventilation than during the two-lung (P = 0.006) or left-lung ventilation (P < 0.001). However, no difference in ETCO₂ was detected between the left-lung and two-lung ventilations. The partial pressure of arterial carbon dioxide (PaCO₂), partial pressure of arterial oxygen (PaO₂), and oxygen saturation (SaO₂) differed among the three types of ventilation (P = 0.003, P = 0.001, and P = 0.001, respectively). The post hoc analyses revealed a higher PaCO₂, lower PaO₂, and lower SaO₂ during right-lung ventilation than during two-lung or left-lung ventilation. However, the levels of these blood gases did not differ between the left-lung and two-lung ventilations. In a pig model of CPR, ETCO₂ was significantly lower during right-lung ventilation than during two-lung ventilation. However, interestingly, ETCO₂ during left-lung ventilation was comparable to that during two-lung ventilation.

New evidence in one-lung ventilation

Mechanical ventilation in thoracic surgery has undergone significant changes in recent years due to the implementation of the protective ventilation. This review will analyze recent ventilatory strategies in one-lung ventilation. A MEDLINE research was performed using Mesh term "One-Lung Ventilation" including randomized clinical trials, metanalysis, reviews and systematic reviews published in the last 6 years. Search was performed on 21st March 2017. A total of 75 articles were initially found. After title and abstract review 14 articles were included. Protective ventilation is not simply synonymous of low tidal volume ventilation, but it also includes routine use of PEEP and alveolar recruitment maneuver. New techniques are still in discussion namely PEEP adjustment, ratio inspiration:expiration, ideal type of anesthesia during one-lung ventilation and hypercapnic ventilation.

The effects of one-lung ventilation mode on lung function in elderly patients undergoing esophageal cancer surgery

The objective of the present study was to explore the effects of different one-lung ventilation (OLV) modes on lung function in elderly patients undergoing esophageal cancer surgery. A total of 180 consecutive elderly patients (ASA Grades I-II, with OLV indications) undergoing elective surgery were recruited in the study. Patients were randomly divided into 4 groups (n = 45). In Group A, patients received low tidal volume (VT < 8 mL/kg) + pressure controlled ventilation (PCV), low tidal volume (VT < 8 mL/kg) + volume-controlled ventilation (VCV) in Group B, high tidal volume (VT ≥ 8 mL/kg) + PCV in Group C and high tidal volume (VT ≥ 8 mL/kg) + VCV in Group D. Two-lung ventilation involved routine tidal volume (8-10 mL/kg) at a frequency of 12 to 18 times/min, and VCV mode. Clinical efficacy among 4 groups was compared. The partial pressure of end-tidal carbon dioxide (PetCO2) did not significantly differ among 4 groups (all P > .05), and the oxygenation index and SO2 in Group A were significantly higher than in the other groups (P < .05). The PetCO2, peak airway pressure (Ppeak), platform airway pressure (Pplat), and mean airway pressure (Pmean) in Group A were significantly lower than those in the other groups (all P < .05). However, airway resistance (Raw) among 4 groups did not significantly differ (all P > .05). The incidence of pulmonary infection, anastomotic fistula, ventilator-induced lung injury, lung dysfunction, difficulty weaning from mechanical ventilation, and multiple organ dysfunction in Groups A and B were lower than that in Groups C and D (all P < .05). The expression levels of IL-6, tumor necrosis factor-α, and C-reactive protein in lavage fluid in Group A were significantly lower than those in the other groups (all P < .05). OLV with low tidal volume (VT < 8 mL/kg) + PCV (5 cmH2O PEEP) improved lung function and mitigated inflammatory responses in elderly patients undergoing esophageal cancer surgery.

The History of One-Lung Anesthesia and the Double-Lumen Tube

One-lung anesthesia presents many practical, anatomical, and physiological challenges to the anesthetist in modern day practice. The techniques and equipment that we use today have developed slowly over the course of the last century. The idea of isolated lung ventilation came from bronchospirometry studies by pioneering physiologists as early as 1871, and some of their original equipment was adapted for clinical use in the 1930s. Anesthetic techniques have generally been developed to facilitate surgical advances, and the development of double-lumen tubes is no exception. The development of the double-lumen tube was sporadic and occurred mainly to allow more complex thoracic procedures, mostly associated with suppurative lung disease. Once the need for independent ventilation of the lungs was identified in clinical practice, pioneers of the technique developed their own methods and often their own equipment. This led to the ability of the anesthetist to be able to control ventilation to each lung, including collapse of the operative lung and protection of the isolated lung against contamination. As these anesthetics became more reliable, the surgical scope for one-lung anesthesia began to broaden, and today one-lung ventilation is used to facilitate thoracic surgery, mainly on the lung, but also esophageal, thoracic wall, and mediastinal surgical procedures.

Effect of low tidal volume with PEEP on respiratory function in infants undergoing one-lung ventilation

BACKGROUND

An increasing number of studies have shown that low tidal volume (TV) with positive end-expiratory pressure (PEEP) offers lung protection during one-lung ventilation (OLV). Considering the unique physiological characteristics of infants, we aimed to determine the feasibility and effect of low TV with PEEP in infants undergoing OLV during thoracoscopy.

PATIENTS AND METHODS

We randomized 60 infants to a conventional group (group I: TV, 8-10 ml/kg; RR, 23-45 bpm; PEEP, 0 cmH₂O) or a low TV with PEEP group (group II: TV, 5-7 ml/kg; RR, 23-45 bpm; PEEP, 4-6 cmH₂O). Arterial blood gas analyses were performed at four time points: 5 min of two-lung ventilation (TLV, T₀), and 20 min, 40 min, and 60 min of OLV (T₁, T₂, T₃); hemodynamic parameters (heart rate, mean blood pressure), temperature, as well as gas exchange (SpO₂ and P_ETCO₂) and ventilation parameters (FiO₂, PEEP, P_max) were recorded simultaneously. Lung compliance and shunt were also calculated.

RESULT

No significant difference was found between both groups at T₀. Compared with T₀, P_ETCO₂, P_max, PaCO₂, lactic acid, and intrapulmonary shunt volume (Qs/Qt) were increased while PaO₂ and respiratory system compliance (Cdyx) were decreased noticeably in both groups at T₁, T₂, and T₃. At T₁, T₂, and T₃, P_max and Qs/Qt were much lower while P_ETCO₂, PaCO₂, and Cdyx were higher in group II than in group I. There was no significant difference in lactic acid and PaO₂ measurements between the two groups at T₁, T₂, and T₃.

CONCLUSION

Low TV with PEEP could be an effective intraoperative ventilation strategy for infants undergoing OLV during video-assisted thoracoscopic surgery and may reduce the risk of lung injury. However, this strategy, as well as the influence of intraoperative hypercapnia on infants, needs further investigation.

A comparison of extraluminal and intraluminal use of the Uniblocker in left thoracic surgery: A CONSORT-compliant article

BACKGROUND

The aim of this study was to assess the feasibility and safety issues concerning extraluminal use of the Uniblocker for one-lung ventilation (OLV) in the left thoracic surgery.

METHODS

Forty patients undergoing elective left thoracic surgery were included in this study, and all patients were randomly allocated to extraluminal use of Uniblocker group (E group, n = 20) or intraluminal use of Uniblocker group (I group, n = 20). Time for intubation, time for verification of the correct position of Uniblocker, incidence of Uniblocker displacement, index of pulmonary collapse, mean arterial pressure, heart rate, peak airway pressure, oxygen saturation in two-lung ventilation, and 30 minutes after OLV, bronchial damage after OLV, sore throat, and hoarseness postoperative were recorded.

RESULTS

The time for positioning Uniblocker was 112.6 ± 31.2 seconds in intraluminal use group, whereas the time for positioning Uniblocker was significantly shorter in extraluminal use group (63.4 ± 15.8 seconds). The incidence of main bronchial injury, the time of intubation, the incidence of Uniblocker malposition after initial placement, the time of OLV, the degree of pulmonary collapse, mean arterial pressure, heart rate, peak airway pressure, oxygen saturation in two-lung ventilation, and 30 minutes after OLV, the incidence of sore throat and hoarseness postoperative have no statistical significance (P > .05).

CONCLUSION

Extraluminal use of the Uniblocker was proved to be a more rapid and more accurate method than conventional intraluminal use of the Uniblocker for OLV in left thoracic surgery.

COMPARATIVE ASPECTS OF RESPIRATORY SUPPORT VIA LARINGEAL AIR DUCTS AND ENDOTRACHEAL TUBE FOR VIDEO-ASSISTED ONKOTHORACIC OPERATIONS

GOAL

To improve patient 's recovery after video-assisted thoracoscopic lobectomies (VATSL) by laryngeal mask using.

METHODS

This is a comparative analysis of 74 patients underwent VATSL. In 37 patients anaesthesia consisted of sevoflurane and fentanyl, myorelaxant, respiratory support via independent ventilation of either lung. In another 37patient 's anaesthesia protocol included respiratory support performed via laryngeal mask, propofol infusion and epidural analgesia with ropivacaine 0,2% and fentanyl. During the operation in both groups we evaluated hemodynamic, arterial blood gases, leukocytes, glucose and cortisol blood level, time to consciousness restoration (Aldrete-score) and time to discharge from ICU and duration of hospital stay, frequency of complications.

RESULTS

Patients with ventilation through laryngeal mask showed a statistically lower stress-reaction, avoided bronchoscopy with BAL and frequency of complications. Duration of inhospital stay in patients with laryngeal mask was 7±1,3 days; in intubated patients was 11±3,2 days.

CONCLUSION

In case of ventilation through the laryngeal mask hyper dynamic state of circulation, glycemia, leukocytes, cortisol blood level and arterial blood pH were lower, whereas Pa CO₂ increase. The number of bronchoscopy with BAL and time to discharge from ICU and from hospital not having risk of postoperative complications --lower.