The use of a bronchial blocker compared with a double-lumen tube for single-lung ventilation during minimally invasive direct coronary artery bypass surgery

The Use of a Bronchial Blocker Compared With a Double-Lumen Tube for Single-Lung Ventilation During Minimally Invasive Direct Coronary Artery Bypass Surgery Jo¨rg Ender, MD, Andreas M. Bury, MD, J. Raumanns, MD, S. Schlu¨nken, MD, H. Kiefer, MD, W. Bellinghausen, MD, and A. Petry, MD Objective: To investigate whether a bronchial blocker (BB) placed through a routinely used single-lumen tube (SLT) to achieve 1-lung ventilation is appropriate in patients undergoing a minimally invasive direct coronary artery bypass (MIDCAB) operation. Design: Clinical trial. Setting: University hospital. Participants: Patients scheduled for elective MIDCAB operation (n ⴝ 159). Interventions: Group A was treated with a left-sided double-lumen tube (DLT) and served as the control group. Group B was intubated with a routinely used SLT in combination with a BB. Measurements and Main Results: The following data were collected: (1) time required for placement of each tube, (2) ventilation pressures, (3) lung compliance, (4) dislocations of the DLT or BB, (5) effectiveness of lung collapse, and (6) PaO2 and fraction of inspired oxygen. In 4 patients (4%) of group B, the BB could not be placed within an acceptable time so

that 155 patients (50 patients in group A, 105 patients in group B) were statistically analyzed. Statistically significant differences during 1-lung ventilation were found for peak and mean inspiratory pressure (p < 0.001 and p < 0.05), dynamic and static lung compliance (p < 0.05), and dynamic lung compliance change (p < 0.01). No statistical significance was found for intubation time (p > 0.05) and PaO2 and fraction of inspired oxygen (p > 0.05). Lung collapse was insufficient in 1 patient of group A (2%) and in 2 patients of group B (2%). Conclusion: To achieve 1-lung ventilation during a MIDCAB procedure, the use of a BB combined with an SLT is an appropriate technique as an alternative to the commonly used DLT. Copyright 2002, Elsevier Science (USA). All rights reserved.

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and propofol, 150 to 300 mg/h. Routine monitoring included a 5-channel electrocardiogram, pulse oximetry, invasive arterial blood pressure, and central venous pressure. Both groups were volume-controlled ventilated with a tidal volume of 8 to 10 mL/kg during 2-lung ventilation (TLV) and during OLV. Breaths per minute were adjusted to achieve normocapnia or mild hypocapnia, controlled by end-expiratory capnography and arterial blood gas analysis. Group A was intubated with a left-sided DLT in the routine fashion. Correct placement was controlled with a fiberoptic bronchoscope (Pentax, Japan). Just before opening of the pleura by the surgeon, the bronchial part of the DLT was clamped so that the left lung collapsed. At the end of surgery, the DLT was changed to an SLT to facilitate respiratory weaning in the intensive care unit. Patients in group B were treated with a commonly used HiLo-SLT and a 6-French (F) BB. The Ruesch BB is a 6-F, 100-cm-long, flexible plastic catheter with a spherical (ie, total cuff length nearly equal to midcuff diameter) balloon at the distal end. The BB balloon can be filled with up to 5 mL of air. The swivel adapter is equipped with 1 free port through which the BB and a fiberoptic bronchoscope can be advanced. The port is sealed by a standard plastic cap, which further fixes the BB into position. The coaxial port is connected to the HiLotube and the nearly 90° angled port for connection to the respirator (Figs 1 and 2). This BB originally was developed for bronchography. It has a balloon on the tip and a small inner lumen for injection of the contrast agent. The inner lumen is too small to allow for effective suctioning. In this study, the BB was inserted into the left mainstem bronchus, then inflated, preventing ventilation of the left lung. The SLT was introduced with a 90° counterclockwise rotation after passing the vocal cords so that the distal end of the SLT was directed toward the left mainstem bronchus. After lubrication with a medical-silicone spray, the BB was placed under fiberoptic control by a swivel adapter through the inner lumen of the SLT into the left mainstem bronchus. Just before skin incision and after ventilation with a fraction of inspired oxygen (FIO2) of 1, the SLT was disconnected from the respirator (Cato, Dra¨ger, Germany) for about 15 seconds, allowing both lungs to collapse. The BB was inflated under fiberoptic control with ⱕ5 mL of air until sufficient blockage of the left mainstem bronchus was achieved, preventing reinsufflation of the left lung after reconnection to

OR A MINIMALLY invasive direct coronary artery bypass (MIDCAB) operation, 1-lung ventilation (OLV) is required to create optimal conditions for the surgeon. In clinical practice the use of a double-lumen endobronchial tube (DLT) is the method of choice to achieve OLV.1 Alternative methods, such as Univent tubes,2 Fogarty occlusion catheter,3 or Foley catheter,4 are described as case reports in the literature. This study compares the use of a bronchial blocker (BB) placed through a routinely used single-lumen tube (SLT) in patients scheduled for a MIDCAB procedure with the DLT technique. METHODS Following the guidelines of the local ethics committee, 159 patients scheduled for elective MIDCAB operations were enrolled in this prospective, clinical observation study from September 1998 until October 1999. Two groups were created: The first 50 patients (group A), who served as the control group, were treated with a left-sided polyvinylchloride DLT (Mallinckrodt, Hennef, Germany) in the routine manner. The next 109 patients (group B) were intubated with a conventional HiLo-SLT (Mallinckrodt, Hennef, Germany) and a BB (Ruesch, Boeblingen, Germany), which was placed through the inner lumen of the SLT into the left mainstem bronchus. After premedication with 25 to 50 mg of clorazepate dipotassium orally the evening before and 7.5 mg of midazolam on the day of surgery, routine induction of anesthesia was done with sufentanil, midazolam, and pancuronium for muscle relaxation. Anesthesia was maintained with a continuous infusion of sufentanil, 100 to 250 ␮g/h,

From the Department of Anesthesia and Intensive Care II, Heartcenter, University of Leipzig, Leipzig, Germany. Address reprint requests to Jo¨rg Ender, MD, Klinik fu¨r Ana¨sthesie und Intensivmedizin, Park-Krankenhaus Leipzig-Su¨dost, Stru¨mpellstrasse 41, 04289 Leipzig, Germany. E-mail: ender.cakai@ parkkrankenhaus-Leipzig.de Copyright 2002, Elsevier Science (USA). All rights reserved. 1053-0770/02/1604-0012$35.00/0 doi:10.1053/jcan.2002.125144 452

KEY WORDS: 1-lung ventilation (OLV), bronchial blocker (BB), double-lumen tube (DLT), minimally invasive direct coronary artery bypass (MIDCAB) surgery

Journal of Cardiothoracic and Vascular Anesthesia, Vol 16, No 4 (August), 2002: pp 452-455

BRONCHIAL BLOCKER FOR LUNG VENTILATION DURING MIDCAB SURGERY

453

Cl stat ⫽ tidal volume 共mL兲/Plat. 共cm H 2 O兲 ⫾ PEEP 共cm H 2 O兲 where PIP is peak inspiratory pressure, PEEP is positive end-expiratory pressure, and Plat. is inspiratory plateau pressure. Dislocations of the DLT and the BB were confirmed by fiberoptic assessment after placing the patients in a semioblique position. A DLT or BB was considered malpositioned if it had to be moved ⬎1.5 cm to correct the position. The effectiveness of the lung collapse was ascertained by the heart surgeon; lung collapse was defined as sufficient after attaining a condition of near-total lung collapse, allowing for an undisturbed preparation of the left mammary artery. Intraoperatively the lowest arterial oxygen partial pressure (PaO2) during OLV was related to the FIO2 for calculating PaO2/FIO2. SPSS 8.0 (SPSS, Inc., Chicago, IL) for Windows was used for statistical evaluation. The following data were statistically compared using the Mann-Whitney U test: time required to position each tube, peak and mean inspiratory pressure, and PaO2/FIO2. The Student t-test for independent samples was used to analyze static and dynamic lung compliance; p ⬍ 0.05 was considered to be statistically significant. RESULTS Fig 1.

Correct placement of the BB.

the respirator. At the end of surgery the BB was deflated and withdrawn to achieve TLV again. The following parameters were noted: (1) time required for placement of each tube, (2) ventilation pressures, (3) dynamic and static lung compliance, (4) dislocation of the DLT or BB after initial correct placement, (5) effectiveness of lung collapse, and (6) PaO2 and FIO2. Time required for intubating the patients with the DLT or SLT/BB included direct laryngoscopy, fiberoptic control, and placement of each tube and BB into the desired position. Ventilation pressures (peak, mean, and plateau pressure) were calculated by the respirator. Dynamic lung compliance (CLdyn) and static lung compliance (Clstat) were calculated as follows: CL dyn ⫽ tidal volume 共mL兲/PIP 共cm H 2 O兲 ⫾ PEEP 共cm H 2 O兲

Fig 2.

A total of 159 patients were enrolled in the study. In 4 patients (4%) in group B, the BB could not be placed within an acceptable time so that 155 patients (50 patients in group A and 105 patients in group B) with a mean age of a 61 ⫾ 11 years scheduled for elective MIDCAB procedures were statistically analyzed. The demographic data were comparable in both groups (Table 1). In group A, the following DLTs were used: 35 F in 7 cases (7 women), 37 F in 17 cases (4 women, 13 men), 39 F in 25 cases (25 men), and 41 F in 1 case (1 man). The BB was advanced in 11 patients through a 7.0 F (11 women), in 7 patients (7 women) through a 7.5 F, in 66 patients (8 women, 58 men) through an 8.0 F, in 20 patients (20 men) through an 8.5 F, and in 1 patient (1 man) through a 9.0 F HiLo-tube into the left mainstem bronchus.

BB inserted through an SLT via a swivel adapter.

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ENDER ET AL

Table 1. Demographic Data of Groups A and B A (DLT, n ⫽ 50)

Age (y) Sex Female Male Height (cm) Weight (kg) EF (%)

B (BB, n ⫽ 105)

Total (n ⫽ 155)

61 ⫾ 12

62 ⫾ 11

61 ⫾ 11

11 (22%) 39 (78%) 171 ⫾ 8 79 ⫾ 11 61 ⫾ 15

26 (25%) 79 (75%) 172 ⫾ 8 79 ⫾ 13 59 ⫾ 15

37 (24%) 118 (76%) 172 ⫾ 8 79 ⫾ 13 60 ⫾ 15

difficult, and 8 DLTs (16%) had to be withdrawn approximately 2 cm; in 4 of these 8 patients, cuff hernia occurred. In 2 cases in group B (2%) and in 1 case in group A (2%), the lung collapse was insufficient. Concerning the PaO2/FIO2, there were no significant differences found between the groups (p ⬎ 0.05). In group A, the decrease of PaO2/FIO2 after lung isolation was approximately 70% versus 62% (not significant) in group B (Table 3). DISCUSSION

NOTE. Data are expressed as mean ⫾ SD. Abbreviation: EF, ejection fraction.

In both groups, there were nearly the same mean tidal volumes during TLV (BB, 621 ⫾ 85 mL v DLT, 634 ⫾ 71 mL) and OLV (BB, 536 ⫾ 102 mL v DLT, 497 ⫾ 84 mL). No significant differences were found regarding the median times for intubation and correct placement (group A, 3.0 minutes v group B, 2.0 minutes). Table 2 shows the recorded ventilation pressures during TLV and OLV expressed as median and 25th and 75th percentiles in both groups. The peak and mean inspiratory pressures during OLV were significantly higher in the DLT group (p ⬍ 0.001 and p ⬍ 0.05), whereas no significant differences were seen in the plateau pressures during OLV. The dynamic lung compliance during TLV was nearly identical in both groups (group A, 43.04 ⫾ 12.36 cm H2O v group B, 43.17 ⫾ 11.12 cm H2O). During OLV in group B, dynamic lung compliance was higher than in group A (group B, 29.34 ⫾ 7.92 cm H2O v group A, 24.25 ⫾ 8.1 cm H2O). This difference was significant (p ⬍ 0.01). Dynamic lung compliance decrease after lung isolation was statistically significantly higher in group A (group A, 18.78 ⫾ 10.12 mL/cm H2O v group B, 13.96 ⫾ 7.39 mL/cm H2O; p ⬍ 0.01). The static lung compliance in group B (30.82 ⫾ 13.26 mL/cm H2O) was significantly higher (p ⬍ 0.05) than in group A (25.59 ⫾ 8.08 mL/cm H2O) during OLV, whereas no significant difference was found during TLV (group A, 55.36 ⫾ 10.7 mL/cm H2O v group B, 44.79 ⫾ 13.18 mL/cm H2O). No major intraoperative complications were seen. In 4 patients in group B (4%), the BB could not be placed into the left mainstem bronchus. These patients were excluded from the study and treated with a DLT in the routine manner. In 7 patients (7%) in group B, the BB initially was placed in the right mainstem bronchus, but correction under fiberoptic control was possible in each patient without any problems. Two BBs (2%) dislocated intraoperatively. In 4 patients (8%) in group A, the DLT placement in the left mainstem bronchus was

The principal advantage of a DLT is that it offers the capability of separate access to either side of the lungs for suctioning, fiberoptic bronchoscopy, or different ventilation strategies, without much manipulation of the tube or the cuff. Use of the DLT protects a healthy lung from blood or other secretions coming from the injured lung. In MIDCAB surgery patients, these advantages are nonessential, however, because a controlled lung collapse is required only to achieve optimal conditions for preparation of the left internal thoracic artery and to perform the anastomosis to the left anterior descending artery. No lung injury is expected, and separate lung access should not be demanded. The use of an SLT combined with the BB is an approprate alternative. In this study, there were no differences between the groups concerning the time required for initial tube placement and effectiveness of lung collapse. In 4 patients in group B, the BB could not be advanced into the left mainstem bronchus, although abnormal airways were not the reason. These patients could be intubated with a DLT. Otherwise, there were no further difficulties in advancing the BB into the correct position. In the literature, many case discussions reported that use of a HiLo-tube and BB was the last option used to achieve OLV, owing to problems in correctly positioning the DLT.4-7 The use of a wire-guided endobronchial blocker in those patients has been reported.8 In the authors’ opinion, the use of a HiLo-tube and BB is a fast and safe method to achieve OLV in elective operations because no airway complications should be anticipated. Ginsberg9 drew an analogous conclusion, after conducting ⬎200 thoracotomies using a Fogarty occlusion catheter. Regarding tube sizes of SLTs and DLTs, the following should be noted. The advantage of the SLT is that its lumen has a better inner-to-outer diameter relationship compared with the DLT (ie, small DLT sizes already have relatively bigger outside diameters). Hannallah et al10 found that the lumen of DLT sizes 35F through 41F (Sheridan, Argyle, NY) correspond regarding inner diameter and air flow resistance to HiLo-tubes (Sheridan,

Table 2. Ventilation Pressures of Group A and Group B During OLV and TLV A (DLT, n ⫽ 50) 25th Percentile

PIP (cm H2O) MIP (cm H2O) Plat. (cm H2O)

Median

B (BB, n ⫽ 105) 75th Percentile

25th Percentile

Median

75th Percentile

TLV

OLV

TLV

OLV

TLV

OLV

TLV

OLV

TLV

OLV

TLV

OLV

16.8 5.0 13.0

24.0 8.0 19.75

20.0 7.0 16.0

27.0* 9.0* 23.0

23.0 9.0 21.0

30.3 11.0 28.0

16.8 5.0 14.0

20.0 6.3 18.0

19.0 6.0 16.0

24.0* 8.0* 21.5

22.0 8.0 19.0

27.0 10.0 25.0

Abbreviations: PIP, peak inspiratory pressure; MIP, mean inspiratory pressure; Plat., inspiratory plateau pressure. *P ⬍ 0.05 (statistically significant).

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Table 3. PaO2/FIO2 Between Group A and Group B During OLV and TLV

PaO2/FIO2

A (TLV, n ⫽ 50)

A (OLV, n ⫽ 50)

B (TLV, n ⫽ 105)

B (OLV, n ⫽ 105)

370 (270-495)

110 (90-150)

325 (238-472)

125 (80-153)

NOTE. Data are expressed as median (25th to 75th percentile).

Argyle, NY) sizes 6.0 to 7.0 mm (inside diameter). The outside diameter of the Univent tubes is large as well.11 The disadvantage of tubes with such an inner-to-outer diameter relationship is that there is a greater risk for tracheal traumas,12-14 and they cause an increased pulmonary air flow resistance and ventilation pressure.10 Breathing becomes harder, causing a more difficult weaning.15 Although air flow resistance using the modern DLT is lower than with the previously used red rubber DLTs, the air flow resistance in SLTs is considerably decreased.16 These effects can explain the present results concerning the lower ventilation pressures and higher lung compliance values in the BB group during TLV and OLV. Dislocation after correct placement can be a life-threatening complication in OLV. In this study, there were relatively few dislocations (2% in the BB group v 8% in the DLT group). Klein et al17 found, in more than one third of 200 blind intubated DLTs, dislocations of ⬎0.5 cm after correct tube placement and after positioning the patients for thoracotomy. Dislocations of the tubes can be viewed after placing the patient in a lateral decubitus position or after manipulations of the mainstem bronchus during thoracic surgery; however, perioperative tube movement18 cannot be prevented, even by cuff

inflation. The present study showed fewer tube dislocations, possibly because the MIDCAB patients were turned in a semioblique position so that no excessive pressures were exerted onto the tubes. Fiberoptic control should be done routinely, however.19 A further advantage of the use of a HiLo-tube and BB is that after the MIDCAB operation, the BB and swivel adapter can be withdrawn without changing the HiLo-tube so that the risk of tracheal trauma or lower respiratory tract infection secondary to tube exchange can be minimized. Easily intubated patients may become difficult to intubate because of laryngeal edema or trauma and secretion. Concerning the oxygenation index, the authors found no differences between the groups, although in the BB group both lung halves collapsed initially for about 10 seconds, in contrast to the DLT group, in which only 1 lung collapsed. Use of the BB is cost-effective. Further studies with use of a modified BB (which may be positioned more easily) may show even further significant benefits. The use of a HiLo-tube in combination with a BB shows no greater disadvantages in comparison with the commonly used DLT to achieve OLV. In particular, for MIDCAB operations, the routine use of a BB can be advocated.

REFERENCES 1. Wilson RS: Endobronchial intubation, in Kaplan JA: Thoracic Anesthesia (ed 2). New York, NY, Churchill Livingstone, 1991, pp 371-387 2. Hammer GB, Brodsky JB, Redpath JH: The Univent tube for single-lung ventilation in paediatric patients. Pediatr Anesth 2:55-57, 1998 3. Harvey SC, Alpert CC, Fishman RL: Independent placement of a bronchial blocker for single-lung ventilation: An alternative method for the difficult airway. Anesth Analg 83:1330-1331, 1996 4. Chen KP, Chan HC, Huang SJ: Foley catheter used as bronchial blocker for one-lung ventilation in a patient with tracheostomy—a case report. Acta Anaesthesiol Sin 33:41-44, 1995 5. Arndt GA, DeLessio ST, Kranner PW, et al: One-lung ventilation when intubation is difficult—presentation of a new endobronchial blocker. Acta Anesthesiol Scand 34:356-358, 1999 6. Garcia-Aguado R, Mateo EM, Onrubia VJ: Use of the Univent System tube for difficult intubation and for achieving one-lung ventilation. Acta Anaesthesiol Scand 40:765-767, 1996 7. Arndt GA, Buchinka S, Kranner PW: Wire-guided endobronchial blockade in a patient with a limited mouth opening. Can J Anesth 46:87-89, 1999 8. Arndt GA, Kranner PW, Rusy DA, et al: Single-lung ventilation in a critically ill patient using a fiberoptically directed wire-guided endobronchial blocker. Anesthesiology 90:1484-1486, 1999 9. Ginsberg RJ: New technique for one-lung anesthesia using an endobronchial blocker. J Thorac Cardiovasc Surg 82:542-546, 1981 10. Hannallah MS, Miller SC, Kurzer SI, et al: The effective diameter and airflow resistance of the individual lumens of left polyvinyl-

chloride double-lumen endobronchial tubes. Anesth Analg 82:867-869, 1996 11. Scheller MS, Kriett JM, Smith CM, et al: Airway management during anesthesia for double-lung transplantation using a single-lumen endotracheal tube with an enclosed bronchial blocker. J Cardiothorac Vasc Anesth 6:204-207, 1992 12. Wagner DL, Gammage GW, Wong ML: Tracheal rupture following the insertion of a disposable double-lumen endotracheal tube. Anesthesiology 63:698-700, 1985 13. Hassan A, Low DE, Ganado AL, et al: Tracheal rupture with disposable polyvinylchloride double-lumen endotracheal tubes. J Cardiothorac Vasc Anesth 6:208-211, 1992 14. Fitzmaurice BG, Brodsky JB: Airway rupture from doublelumen tubes. J Cardiothorac Vasc Anesth 3:322-329, 1999 15. Shapiro M, Wilson R, Casar G, et al: Work of breathing through different sized endotracheal tubes. Crit Care Med 14:1028-1031, 1986 16. Slinger PD, Lesiuk L: Flow resistances of disposable doublelumen, single-lumen, and Univent tubes. J Cardiothorac Vasc Anesth 12:142-144, 1998 17. Klein U, Karzai W, Bloos F, et al: Role of fiberoptic bronchoscopy in conjunction with the use of double-lumen tubes for thoracic anesthesia. Anesthesiology 88:346-350, 1998 18. Desiderio DP, Burt M, Kolker AC, et al: The effects of endobronchial cuff inflation on double-lumen endobronchial tube movement after lateral decubitus positioning. J Cardiothorac Vasc Anesth 11:595598, 1997 19. Benumof JL: The position of double-lumen tubes should be routinely determined by fiberoptic bronchoscopy. J Cardiothorac Vasc Anesth 7:513-514, 1993