Rupture of the left main-stem bronchus by the tracheal portion of a double-lumen endobronchial tube

Double lumen tube: Size and insertion depth

Double lumen tubes (DLTs) are most commonly used to achieve one lung ventilation (OLV) in most thoracic surgical procedures unless contraindicated. Left-sided DLT (LDLT) is most commonly used nowadays for most thoracic surgical procedures. Though, the use of LDLT dates long back in history, two clinical and technical issues are yet to be resolved. The first issue is the ideal size of DLT which is defined as that which provides near-complete seal of the bronchial lumen without cuff inflation. There are no guidelines in literature which help in selecting the size of DLT. However, general consensus among thoracic anesthesiologists recommends the use of smaller sizes to avoid airway trauma. In our practice and for the last few years, we are using smaller size LDLT 35 F for females and 37 F for males with minimal airway trauma and had encouraging results. The second issue is the insertion depth of the LDLT. We have introduced a height-based formula to predict the insertion depth of LDLT with encouraging results. However, even with the use of the formula, we still recommend the use of fiberoptic bronchoscopic confirmation method for final positioning of the LDLT.

Lung separation in adult thoracic anesthesia

Thoracic anesthesia is mainly the world of OLV during anesthesia. The indications for OLV, classified as absolute or relative are more representative of the new concepts in OLV: It includes either the separation or the isolation of the lungs. Modern DLTs are most widely employed worldwide to perform OLV including the concept of one lung separation. Endobronchial blockers are a valid alternative to DLTs, and they are mandatory in the education of lung separation and in case of predicted difficult airways as they are the safest approach (with an awake intubation with an SLT through a FOB). Every general anesthesiologist should know how to insert a left-sided DLT, but he/she should also have in his technical luggage and toolbox, basic knowledge and minimal expertise with BBs, this option being considered a suitable alternative, particularly in emergency situation where the patient is already intubated and/or in case of difficult airways. One should keep in mind that extubation or re-intubation after DLT might be difficult too, and additional intubation tools are necessary for the safety conditions.

Comparison between computerized tomography-guided bronchial width measurement versus conventional method for selection of adequate double lumen tube size

Background:

Selection of adequate size double lumen tube (DLT) is complicated by marked inter-individual variability in morphology and dimensions of tracheobronchial tree. Computerized tomography (CT)-guided left bronchus width measurement has been used to predict adequate size DLT in European and Singapore population; however, no such data exist for Indian population who are racially different. We compared the effect of DLT size selection based on CT-guided bronchial width measurement to the conventional method of DLT selection on the adequacy of both lungs isolation and on the safety margin of right-sided DLT.

Methods:

Fifty-five adults scheduled to undergo thoracotomy were enrolled in this prospective observational study. An appropriate size left- or right-sided DLT with outer diameter 0.5–1 mm smaller than the CT-measured bronchial width was selected for the isolation of lungs. Adequacy of separation was checked using fiberoptic bronchoscope. The safety margin of selected right-sided DLT size was calculated from CT-measured right upper lobe bronchus width and diameter of right upper lobe ventilation slot of the DLT.

Results:

Adequate separation of lungs was achieved in 92.7% of studied population, 90.9% in males, and 95.4% in females. Among these, 54.9% patients required different sized DLT as compared to conventional method. Overall safety of margin of right-sided DLTs was comparable between two methods of DLT selection (median [IQR] 4.8 (3.5–6.8) vs. 6.59 (3.5–7.8), P = 0.317). DLT size with adequate isolation of lung correlated with height, tracheal width (TW) on chest X-ray, and age of the patients. A formula to calculate DLT size based on these variable was derived.

Conclusion:

CT-measured bronchial width predicts the appropriate DLT size better than conventional method. In the absence of CT scan facility, patient height, age, and chest X-ray TW may be used to predict DLT size with reasonable accuracy.

[Risk factors for intraoperative hypoxemia during monopulmonary ventilation: an observational study]

BACKGROUND

Left double-lumen endotracheal tubes have been widely used in thoracic, esophageal, vascular, and mediastinal procedures to provide lung separation. Lacking clear objective guidelines, anesthesiologists usually select appropriately sized double-lumen endotracheal tubes based on their experience with 35 and 37Fr double-lumen endotracheal tubes, which are the most commonly used. We hypothesized the patients with a left main bronchus of shorter length (<40mm) had a greater chance of experiencing desaturation during one lung ventilation, due to obstruction in the orifice of the left upper lobe with the bronchial tube.

METHODS

We included 360 patients with a left double-lumen intubated between September 2014 and August 2015. The patient's age, sex, height, weight, and underlying disease were recorded along with type of surgical procedure and the desaturation episodes. In addition, the width of the trachea and the width and length of the left bronchus were measured using computed tomography.

RESULT

Patients with a left main bronchus length of less than 40mm who underwent intubation with a left double-lumen endotracheal tubes had significantly higher incidence of desaturation (Odds Ratio (OR: 8.087)) during one-lung ventilation. Other related factors of patients identified to be at risk of developing hypoxia were diabetes mellitus (OR: 5.368), right side collapse surgery (OR: 4.933), and BMI (OR: 1.105).

CONCLUSIONS

We identified that patients with a left main bronchus length of less than 40mm have a great chance of desaturation, especially if other desaturation risk factors are present.

Lung Isolation in the Patient With a Difficult Airway

One-lung ventilation is routinely used to facilitate exposure for thoracic surgical procedures and can be achieved via several lung isolation techniques. The optimal method for lung isolation depends on a number of factors that include (1) the indication for lung isolation, (2) anatomic features of the upper and lower airway, (3) availability of equipment and devices, and (4) the anesthesiologist's proficiency and preferences. Though double-lumen endobronchial tubes (DLTs) are most commonly utilized to achieve lung isolation, the use of endobronchial blockers offer advantages in patients with challenging airway anatomy. Anesthesiologists should be familiar with existing alternatives to the DLT for lung isolation and alternative techniques for DLT placement in the patient with a difficult airway. Newer technologies such as videolaryngoscopy with or without adjunctive fiberoptic bronchoscopy may facilitate intubation and lung isolation in difficult airway management.

Risk factors for intraoperative hypoxemia during monopulmonary ventilation: an observational study

Background

Left double-lumen endotracheal tubes have been widely used in thoracic, esophageal, vascular, and mediastinal procedures to provide lung separation. Lacking clear objective guidelines, anesthesiologists usually select appropriately sized double-lumen endotracheal tubes based on their experience with 35 and 37 Fr double-lumen endotracheal tubes, which are the most commonly used. We hypothesized the patients with a left main bronchus of shorter length (<40 mm) had a greater chance of experiencing desaturation during one lung ventilation, due to obstruction in the orifice of the left upper lobe with the bronchial tube.

Methods

We included 360 patients with a left double-lumen intubated between September 2014 and August 2015. The patient's age, sex, height, weight, and underlying disease were recorded along with type of surgical procedure and the desaturation episodes. In addition, the width of the trachea and the width and length of the left bronchus were measured using computed tomography.

Result

Patients with a left main bronchus length of less than 40 mm who underwent intubation with a left double-lumen endotracheal tubes had significantly higher incidence of desaturation (Odds Ratio (OR: 8.087)) during one-lung ventilation. Other related factors of patients identified to be at risk of developing hypoxia were diabetes mellitus (OR: 5.368), right side collapse surgery (OR: 4.933), and BMI (OR: 1.105).

Conclusions

We identified that patients with a left main bronchus length of less than 40 mm have a great chance of desaturation, especially if other desaturation risk factors are present.

Rupture of Left Main Bronchus Associated with Radiotherapy-induced Bronchial Injury and Use of a Double-lumen Tube in Oesophageal Cancer Surgery

We report a case of rupture of the left main bronchus in a female patient with oesophageal carcinoma, who had received thoracic radiotherapy preoperatively. Endotracheal intubation was achieved with a left-sided double-lumen tube. After almost three hours of intubation and one and half hours of one-lung ventilation, bronchial injury was detected. Immediate surgical repair of the membranous part of the bronchus was undertaken, as well as completion of the oesophagectomy. Radiotherapy-induced damage to the bronchus was thought to have contributed to the rupture. The presentation, diagnosis and management of intraoperative bronchial rupture are discussed.

The use of ETView endotracheal tube for surveillance after tube positioning in patients undergoing lobectomy, randomized trial

The ETView tracheoscopic ventilation tube (TVT) is a tracheal tube (TT) incorporating a video camera and a light source in its tip. The view from the tip appears continuously on a portable monitor in the anesthesia area. We evaluated the effectiveness and usefulness of the single/double ETView TVT in monitoring the tracheal tube position during general anesthesia undergoing video-assisted thoracoscopic lobectomy.Eighty-three patients with pulmonary bullae (American Society of Anesthesiologists (ASA) I-III) undergoing lobectomy, with general anaesthesia, were included. Patients were randomly assigned to 3 groups, based on the tube ETView double-lumen tube (VDT), ETView single-lumen tube (VST), or traditional double lumen tube (DT).All 83 patients' intubations were successful to achieve 1-lung ventilation: 74 patients at the first attempt (22/26 in VDT, 26/28 in VST, 26/29 in DT group) and 9 patients at the second attempt. The time to achieve 1-lung ventilation with the VDT was 58.5 ± 21.5 (mean ± SD) seconds, the VST was 38.2 ± 10.1 (mean ± SD) seconds, and the DT group was 195.5 ± 40.3 (mean ± SD) seconds. During operations, the ETView tubes provided continuous airway visualization in all patients; a good view was obtained in 24/25 patients in VDT/VST, moderate in 4/12 patients in VDT/VST, and poor in 1/1 patients in VDT/VST. When the patient left the postanesthesia care unit, all had sore throat and 26/15/25 patients in VDT/VST/DT group had hoarseness. All had good outcomes of the surgical operations.We found the ETView tube to be helpful in the endotracheal intubation and continuous surveillance of tube position in patients with video-assisted thoracoscopic lobectomy. The ETView single lumen endotracheal tube had fewer associated complications and is superior to the 2 double-lumen tubes.

One-Lung Anesthesia Update

One-lung ventilation is used during a variety of cardiac, thoracic, and major vascular procedures. Endobronchial tubes, bronchial blockers, and occasionally, single-lumen tubes are used to isolate the lungs. Patients with difficult airways and pediatric patients provide special challenges for lung isolation. Finally, intraoperative hypoxia and hypercarbia in patients with intrinsic lung disease frequently complicate one-lung anesthesia. The concepts and controversies in lung isolation techniques are discussed.

Comparison between transthoracic lung ultrasound and a clinical method in confirming the position of double-lumen tube in thoracic anaesthesia. A pilot study

OBJECTIVE

To compare the ability of lung ultrasound and a clinical method in the confirmation of a selective bronchial intubation by left double-lumen tube in elective thoracic surgery.

MATERIAL AND METHODS

A prospective and blind, observational study was conducted in the setting of a university hospital operating room assigned for thoracic surgery. A single group of 105 consecutive patients from a total of 130, were included. After blind intubation, the position of the tube was confirmed by clinical and ultrasound assessment. Finally, the fiberoptic bronchoscopy confirmation as a reference standard was used to confirm the position of the tube. Under manual ventilation, by sequentially clamping the tracheal and bronchial limbs of the tube, clinical confirmation was made by auscultation, capnography, visualizing the chest wall expansion, and perceiving the lung compliance in the reservoir bag. Ultrasound confirmation was obtained by visualizing lung sliding, diaphragmatic movements, and the appearance of lung pulse sign.

RESULTS

The sensitivity of the clinical method was 84.5%, with a specificity of 41.1%. The positive and negative likelihood ratio was 1.44 and 0.38, respectively. The sensitivity of the ultrasound method was 98.6%, specificity was 52.9%, with a positive likelihood ratio of 2.10 and a negative likelihood ratio of 0.03. Comparisons between the diagnostic performance of the 2 methods were calculated with McNemar's test. There was a significant difference in sensitivity between the ultrasound method and the clinical method (P=.002). Nevertheless, there was no statistically significant difference in specificity between both methods (P=.34). A p value<.01 was considered statistically significant.

CONCLUSION

Lung ultrasound was superior to the clinical method in confirming the adequate position of the left double-lumen tube. On the other hand, in confirming the misplacement of the tube, differences between both methods could not be ensured.

Which device should be considered the best for lung isolation: double-lumen endotracheal tube versus bronchial blockers

PURPOSE OF REVIEW

This review is a clinical comparison between double-lumen endotracheal tubes and bronchial blockers to determine which device is considered the best for lung isolation.

RECENT FINDINGS

Double-lumen endotracheal tubes and bronchial blockers have been found to be clinically equivalent in terms of performance in providing lung collapse for patients with normal airways. In the last five years, however, numerous reports have indicated a preference for the use of bronchial blockers in patients with airway abnormalities. For nonthoracic anesthesiologists who have limited experience in thoracic anesthesia cases, none of the devices (double-lumen tubes or bronchial blockers) have been shown to provide any advantage while in use due to a high incidence of unrecognized malpositions. Overall, each device provides advantages depending upon the case, such as absolute lung separation with a double-lumen endotracheal tube or the use of a bronchial blocker in a difficult airway for a patient requiring lung isolation.

SUMMARY

Double-lumen endotracheal tubes and bronchial blockers should be part of the armamentarium of every anesthesiologist involved in lung isolation techniques and every device should be tailored to specific case needs.

Optimal depth of insertion of left-sided double-lumen endobronchial tubes cannot be predicted from body height in below average-sized adult patients

BACKGROUND AND OBJECTIVE

The optimal depth of insertion of left-sided double-lumen endobronchial tubes is strongly correlated with body height in average-sized adults. However, this relationship has not been studied in below average-sized adult patients. We investigated whether or not there is a clinically useful relationship in below average-sized adult patients.

METHODS

One hundred and ninety six consecutive adult patients undergoing thoracic surgery under one-lung anaesthesia (body height < or = 155 cm) were included in this study. Left-sided double-lumen tubes were inserted under the guidance of a fibre-optic bronchoscope. Optimal depth was defined as the proximal surface of the bronchial cuff positioned just below the carina.

RESULTS

There was a statistically significant positive correlation between body height and the optimal depth of insertion (r = 0.61, P < 0.0001); however, the correlation coefficient was low. The actual optimal depth of insertion of one patient was even 4.5 cm shorter than that obtained from the equation.

CONCLUSION

Although there was a statistically significant correlation between body height and the optimal depth of insertion of left sided double lumen tubes in adult patients of short stature (< or = 155 cm), clinical application of the equation is not warranted and these tubes should be inserted under direct vision with a fibre-optic bronchoscope.

Progress in lung separation

The progress in lung separation technology has allowed anesthesiologists to become skillful in fiberoptic bronchoscopy techniques and to provide excellent lung exposure in thoracic surgery patients. Given the availability of two technologies--DLTs (right-sided and left-sided) and bronchial blocker technology (TCBU, Arndt, and Cohen--every case that requires lung collapse and OLV should receive the benefit of these devices. Because of its greater margin of safety, a left-sided DLT is the more common device used in lung separation. If any contraindication to placing a left-sided DLT exists, a right-sided DLT is an option for any specific situation (eg, left lung transplantation). For a patient who requires lung separation and presents with the dilemma of a difficult or abnormal airway, bronchial blockers offer more advantages. Regardless of the device used, the optimal position of these devices (DLTs and bronchial blockers) is achieved best with the use of fiberoptic bronchoscopy techniques first in supine and then in lateral decubitus position or whenever repositioning of the device is needed.

Bilateral pneumothoraces, pneumomediastinum, pneumoperitoneum, pneumoretroperitoneum, and subcutaneous emphysema following intubation with a double-lumen endotracheal tube for thoracoscopic anterior spinal release and fusion in a patient with idiopathic scoliosis

Recently, thoracoscopic approaches to the spine have taken on greater clinical applications in the treatment of spinal deformity with generally good results. However, the steep learning curve must be ascended by the surgeon and may lead to complications early in one's experience. There also exists a learning curve for the anesthesiologist to become adept at obtaining single lung ventilation and managing this throughout the operative procedure. We report a case of an 11-year-old patient with severe scoliosis who developed air in both chest cavities, mediastinum, peritoneum, retroperitoneum, and subcutaneous tissue after intubation with a double-lumen endotracheal tube. The patient remained hemodynamically stable throughout this period, and bilateral chest tubes were placed. The patient remained on the ventilator for 24 hours and was extubated without sequelae. Complications from a thoracoscopic approach to the spine for deformity are most often attributed to the learning curve of the surgeon; however, the entire operative team becomes exposed to the challenges of performing this procedure. This report documents a life-threatening complication of air throughout the chest, mediastinum, abdomen, and subcutaneous tissues in a patient with severe scoliosis.

Tracheobronchial injuries in childhood: review of two cases

Penetrating injuries of the tracheobronchial tree in children are very rare. With prompt diagnosis nonoperative treatment seems to be appropriate and safe without complications. Delayed diagnosis may result in surgical exploration with severe complications afterwards caused by poor condition at the time of intervention. Two children with penetrating tracheobronchial injuries were referred to our pediatric surgical center in the last 12 years. A 10-year-old boy suffered an iatrogenic penetrating injury of the tracheobronchial tree, and a 6-year-old boy a direct penetrating injury of the distal trachea in an agricultural accident. Cervical emphysema and bronchoscopy identified the lesion in these patients. Both of them could be treated conservatively without any sequelae.

Predicting the size of a double-lumen endobronchial tube using computed tomographic scan measurements of the left main bronchus diameter

We investigated the use of chest computer tomographic (CT) scan measurement of the left mainstem bronchial diameter to predict the correct left-sided double-lumen endobronchial tube (DLT) size in Asian patients who may require smaller DLT sizes. Fifty consecutive Asian adults aged 17-80 yr with preoperative chest CT scans undergoing elective thoracic surgery were entered into the study. The measurements of the left main bronchus diameter were made by using the electronic calipers of the spiral scanner to the nearest millimeter. The sizes of DLT selected were 32F, 35F, 37F, 39F, and 41F for left main bronchus diameters of <10 mm, 10 mm, 11 mm, 12 mm, and >12 mm, respectively. All DLT placements were confirmed and positioned by using fiberoptic bronchoscopy. The tracheas of all patients were successfully intubated with the predicted DLT sizes. Thirty-four patients (68%) were predicted to require smaller DLTs (37F or smaller). Six patients were correctly predicted to receive 32F DLTs. Twelve patients (24%) received an oversized DLT, but none received an undersized DLT. The overall positive predictive value for the male and female patients was 84.4% and 61.1%, respectively. Our study showed that CT scan measurements of the diameter of the left bronchus were especially useful in choosing smaller DLTs.

IMPLICATIONS

We used computer tomographic scans to measure the diameter of the left mainstem bronchus, then selected the size of the left-sided double-lumen endobronchial tube (DLT) accordingly. We found that we could predict the sizes of the DLT fairly accurately, especially the smaller DLTs.

Predicting the size of a double-lumen endobronchial tube based on tracheal diameter

We assessed whether using the tracheal diameter to predict the correct size of the left double-lumen endobronchial tube (DLT) could be used for our generally smaller sized Asian patients. Sixty-six consecutive adult patients under anesthesia for elective surgery requiring the use of a DLT were studied. The size of the left-sided DLT used was based on the width of patients' trachea measured from the preoperative posterior-anterior chest radiograph. The placement of the DLT was standardized and confirmed with fiberoptic bronchoscopy. The correct size of the DLT was the largest size tube inserted into the left bronchus with a small air leak detectable when the endobronchial cuff was deflated but not exceeding the recommended resting volume when inflated for lung isolation. Using this method of choosing our DLT, we found that an oversized DLT was often chosen especially among our female Asian patients. The overall positive predictive values for the male and female patients were 77.3% and 45.5%, respectively. We postulate that this could be due to our criteria for correct DLT size or that our local Asian patients, especially the females, were smaller and shorter.

IMPLICATIONS

This study assessed whether the correct double-lumen endobronchial tube size could be predicted from tracheal diameter measurements taken from the chest radiograph. We found that this method of choosing the double-lumen endobronchial tubes was not always reliable.