Double-Lumen Endobronchial Tube Intubation in Patients with Difficult Airways Using Trachlight® and a Modified Technique

Abstract

We present a modified method for the insertion of double-lumen endobronchial tubes with Trachlight® in patients with difficult airways. We also discuss whether our method is applicable to smaller double-lumen endobronchial tubes.

In Brief

IMPLICATIONS: A Trachlight® can be used to guide a double-lumen endotracheal tube during intubation by cutting a small slit in the bronchial lumen just proximal to the pilot balloon tube.

Double-lumen endobronchial tubes (DLTs) are the lung separation technique of choice for thoracic surgery (¹). Although DLTs are frequently used in clinical practice, they can be challenging to place in patients with difficult airways. The Trachlight® (Laerdal Medical Corporation, NY) uses tracheal transillumination to facilitate intubation (²). We present two patients with difficult airways who were intubated with a DLT and Trachlight.

CASE REPORTS

Case 1

A 79-yr-old man was scheduled for an elective thoracocentesis. He weighed 45 kg and was 160 cm tall. His preoperative airway assessment revealed poor dentition, an interincisor gap (mouth opening) of <2 cm, and limited head-neck extension. There was a limited view of his posterior pharynx (Mallampati Class 3).

A difficult airway cart with a fiberoptic bronchoscope, a cricothyroidotomy kit, and a retrograde guidewire was in the operating room during the intubation. The DLT and Trachlight were prepared as follows. A 2-cm longitudinal incision was made in the bronchial lumen, just above the point where the bronchial cuff pilot tube emerges. The tip of the Trachlight wand was lubricated and inserted into the bronchial lumen via the opening just created. The Trachlight wand was then shaped, to the 90 degrees “hockey-stick” configuration (Fig. 1).

Figure 1.: The double-lumen tube (DLT) combined with Trachlight®.

Electrocardiogram electrodes, peripheral oxygen saturation, and noninvasive arterial blood pressure monitors were applied before induction. The patient was administered 100% oxygen via a facemask for 5 min. Anesthesia was then induced with fentanyl 100 μg and sodium thiopental 250 mg. After loss of consciousness, manual ventilation was provided via a facemask.

Given his poor dentition, mouth guards were used to cover both upper and lower incisors to minimize the possibility of tearing the DLT cuff. After administration of succinylcholine 60 mg, the DLT with Trachlight was placed in the patient's oropharynx. When the glow from the Trachlight could be seen in the midline of the thyroid prominence, we gently advanced the tip 1–2 cm until resistance was felt. The DLT was then held against the lips and the Trachlight stylet was retracted approximately 10 cm, followed by removal of the Trachlight wand. The DLT was rotated 90 degrees and advanced into the left mainstem bronchus. Tegaderm™ (3M Health Care, MN) adhesive tape was used to seal the cut opening to prevent air leakage. We verified the DLT position using a fiberoptic bronchoscope.

Case 2

A 74-yr-old man was scheduled for decortication due to a right hemothorax. He weighed 73 kg and was 157 cm tall. His preoperative airway assessment revealed poor dentition and a thyromental distance of <6 cm. Only his hard palate was visible on oral inspection (Mallampati Class 4). The DLT and Trachlight were prepared as described above.

Electrocardiogram electrodes, peripheral oxygen saturation, and noninvasive arterial blood pressure monitoring were placed, and the patient was administered 100% oxygen via a facemask for 5 min. Anesthesia was induced with fentanyl 100 μg and sodium thiopental 250 mg. After loss of consciousness, manual ventilation was provided via a facemask. Succinylcholine 80 mg was then administered, followed by direct laryngoscopy, which was confirmed as a Cormack Grade III view. After removal of the laryngoscope, the DLT with Trachlight was placed in the patient's oropharynx. Once translumination in the midline of the thyroid prominence was visualized, the DLT was advanced into the trachea. The Trachlight wand was removed and the tube was rotated 90 degrees and advanced into the left mainstem bronchus. We verified the DLT position with a fiberoptic bronchoscope.

DISCUSSION

Placement of a DLT can be challenging in patients with difficult airways. Intubation with the Trachlight is easy and inexpensive. The Trachlight has been advocated for patients who are unintubatable by direct or fiberoptic laryngoscopy. Hung et al. (³) used Trachlight in 265 patients with anticipated or unexpected difficult intubation. Tracheal intubation of all these patients was successful except in two patients who were grossly obese.

The use of muscle relaxants increases the success rate of tracheal intubation with the Trachlight. Masso et al. (⁴) compared the efficiency of Trachlight orotracheal intubation with and without muscle relaxation in patients with normal airway anatomy. Muscle relaxants increased the success rate, decreased intubation time, and resulted in fewer attempts during Trachlight orotracheal intubation. Hung et al. (³) used Trachlight with a muscle relaxant in anticipated or unexpected difficult intubation patients after controlled ventilation was secured.

Scanzillo and Shulman (⁵) used a lighted stylet to facilitate the placement of a DLT in patients who were difficult to intubate. Given that the DLT is much longer than the lighted stylet, they cut 2.5 cm off both lumina from a 37F DLT to allow the lighted stylet to reach the end of the tube. This technique cannot be used with the Trachlight, because the adult Trachlight wand is too thick to pass through the Y bifurcation of a Broncho-Cath DLT. Besides, the adult size Trachlight wand is too short (34 cm) to reach the distal end of a DLT.

Watanabe (⁶) describes a clever approach to using a Trachlight with a DLT. Although the Trachlight wand is shorter than the DLT, Watanabe combined two Trachlight wands to form a single longer wand, which could be modified to fit DLTs of different sizes. This approach has some inherent risks. First, the joined wands may come apart during removal. Second, the internal diameter of a DLT is narrowest at the Y bifurcation, and this varies with different manufacturers. The Trachlight wand is just able to pass through a 37F Broncho-Cath DLT, but could not pass through a 35F Broncho-cath DLT.

Our technique has some advantages. First, one does not have to cut off either lumina of the DLT, preserving structural integrity. Second, if a smaller DLT is required (such as a 32F or 28F), the wand can be changed from the adult size to child size to fit within the smaller bronchial lumen.

The bronchial cuff pilot tube of the Broncho-Cath DLT emerges at a length of 29 cm. In our modified method, the adult-sized Trachlight wand (34 cm) can be used in a Broncho-Cath DLT larger than 35F. The child-sized Trachlight wand (31 cm) can be used in a Broncho-Cath DLT larger the 28F. However, the infant-sized Trachlight wand (22 cm) is too short to incorporate any size of Broncho-Cath DLT (Table 1).

Table 1: The Relationship Between Trachlight® Wand Size and Broncho-Cath Double-Lumen Tube (DLT) Size With Our Modified Method

The Trachlight can be used in clinical settings where direct visualization is difficult, such as in the presence of blood or secretions. It is less invasive than retrograde intubation, which can result in infection, hematoma, or pneumomediastinum (⁷). Moreover, Trachlight is a better choice than direct laryngoscopy in patients with unstable dentition (⁸) as it will do less damage to a patient's teeth.

In conclusion, Trachlight intubation is a simple technique, easily learned, and may be useful when direct laryngoscope and fiberoptic laryngoscopy are difficult. It can also be used with a DLT with only a very minor modification to permit passage of the Trachlight.