Comparing Arndt and Tappa Endobronchial Blocker During Pediatric One Lung Ventilation

A Prospective Randomized Trial Comparing the Application of Arndt and Tappa Endobronchial Blocker During Pediatric One Lung Ventilation

This study aims to evaluate the efficacy and ease of placement of two different endobronchial blockers(Arndt and Tappa blocker) for pediatric patients undergoing thoracotomy. Time from laryngoscopy to successful insertion of the blocker by an experienced anaesthetist will be recorded and the difficulty of placement of the blocker will be assesed. We plan to evaluate the lung collapse and also observe the effect of two different bronchial blockers on patients' ventilation and oxygenation and adverse events such as desaturation, failed one lung ventilation.Our primary outcome is the time from laryngoscopy to successful insertion of the bronchial blocker by an experienced anaesthetist. Our secondary outcomes are effects of two different bronchial blockers on lung isolation score, ease of placement of the bronchial blocker, mechanical ventilation parameters (tidal volume, respiratory rate, peak airway pressure, plateau pressure, compliance), intraoperative blood gas analysis (paO2, pCO2, saO2, lac), frequency of malposition after successful blocker placement, surgical exposure and complications.

Many techniques for one lung ventilation exist including the use of double-lumen tubes, endotracheal tubes and bronchial blockers. The choice of lung isolation technique depends on the age, the size of the patient, experience of the anaesthetist and type of the surgery. The use of double lumen tube for one lung ventilation is very common. However, it may be challenging and hazardous in some cases such as pediatric patients, patients with tracheostomy, difficult airway scenarios. Endobronchial blockers can be used for these cases. Bronchial blockers have high-volume,low-pressure balloons so they are less likely to cause damage to the airway mucosa while achieving a successful lung isolation. Arndt blocker has a low-pressure, high-volume balloon, a multiport airway adapter and a guide loop. On the other hand, Tappa bronchial blocker has an auto inflation balloon, and a high volume low pressure cuff. It also has 'Tappa angle' which is designed as per human anatomy which makes it easier to insert. In our study, we aim to compare the efficacy and ease of placement of Arndt and Tappa blocker for pediatric one lung ventilation. Our primary outcome is the time from laryngoscopy to successful insertion of the bronchial blocker by an experienced anaesthetist. Secondary outcomes are effects of two different bronchial blockers on lung isolation score, ease of placement of the bronchial blocker, mechanical ventilation parameters (tidal volume, respiratory rate, peak airway pressure, plateau pressure, compliance), intraoperative blood gas analysis (paO2, pCO2, saO2, lac), frequency of malposition after successful blocker placement, surgical exposure and complications. The difficulty of placement of the blocker will be assesed by a 5-point scale (1:very easy, 5:impossible) and the lung collapse will be evaluated by using a 10-point scale (10: complete collapse).

Arndt endobronchial blocker, Tappa endobronchial blocker, Pediatrics, One lung ventilation, Thoracic Surgery

After orotracheal intubation, Tappa endobronchial blocker will be inserted using a broncoscope by an experienced anaesthetist. Time from laryngoscopy to successful placement of the endobronchial blocker will be recorded.

After orotracheal intubation, Arndt endobronchial blocker will be inserted using a broncoscope by the experienced anaesthetist. Time from laryngoscopy to successful placement of the endobronchial blocker will be recorded.

After intubation, the Tappa bronchial blocker will be advanced either through the intubation tube or outside the tube using a fiberoptic broncoscope. Once the position of the blocker is confirmed, the cuff of the blocker will be inflated with 1-3 mL of air. Since Tappa blocker has an autoinflation system, the anaesthetist can both inflate the cuff with one hand and operate the fiberoptic broncoscope at the same time.

After intubation, the endobronchial blocker will be passed through a multiport airway adapter that is placed at the proximal end of the tracheal tube.The fiberoptic broncoscope will be passed through the port and then through the guidewire loop at the end of the blocker. The bronchial blocker and the broncoscope will be advanced as a single unit into the target part of a right or left lung. The broncoscope will be withdrawn into the trachea and the blocker cuff will be inflated and the position of the blocker will be confirmed using the fiberoptic broncoscope. The wire loop will be removed after correct placement of the blocker. Once the guide wire is removed, the blocker can't be replaced.

Time from laryngoscopy to correct insertion of the bronchial blocker by an experienced anaesthetist will be recorded.

Lung collapse will be assesed at 5,10,15,and 20 minutes after pleural opening using a 10-point scale by the surgeon. 1 point refers to the inflated lung and 10 point refers to a completely collapsed lung.

The anaesthetist will rate the difficulty of placement of the bronchial blocker using a 5-point scale, 1 point being very easy and 5 points being impossible to insert.

Frequency of malposition of the bronchial blocker after successful bronchial blocker placement will be recorded if the blocker displaces.

Inclusion Criteria: Pediatric patients undergoing thoracic surgery American Society of Anesthesiology Class 1-2-3 Exclusion Criteria: Denial of patients or parents Coagulopathy With preexisting cardiac dysfunction Wtih history of renal and/or hepatic dysfunction

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One lung ventilation strategies for infants and children undergoing video assisted thoracoscopic surgery

Successful one-lung ventilation by blocking the right intermediate bronchus in a 7-year-old child: a case report