Insertion Depth of Left-sided Double-lumen Tube: a New Predictive Formula

Imam Abdulrahman Bin Faisal University

Status: Completed

Conditions: Left-sided Double Lumen Tube; One Lung Ventilation; Thoracic Surgery

Treatments: Other: Predicted depth of insertion; Other: Adjustment of depth of insertion; Other: Optimized depth of insertion

Study type: Interventional

Funder types: Other

Identifiers

NCT04329416

E-18-3064

Details and patient eligibility

About

The authors developed a formula for predicting the accurate depth of DLT insertion into the appropriate bronchus based on height as follows [The predicted insertion depth of left DLT (cm) equals 0.249 × (BH)0.916] [R]. That pilot study showed comparable correlations between five formulae [Brodsky et al, Bahk and Oh R, Takita et al, Chow et al, Lin]. However, that formula developed has not been validated yet.

We hypothesized that previously published formula would predict the accurate depth of left-sided DLT insertion. We aimed to investigate the efficacy of this formula to estimate the optimum insertion depth of the DLT using a flexible bronchoscope and decrease the incidence of DLT displacement into the appropriate bronchus, the need for bronchoscopic adjustment, and complications including soreness of throat and mucosal injury.

Full description

Accurate placement of the double-lumen tube [DLT], the commonly used tool to provide one-lung ventilation during thoracic surgery, is a real challenge for the thoracic anesthesiologists. Optimal DLT depth, defined as the blue endobronchial cuff below the carina, would decrease the incidence of obstructing the trachea and the contralateral bronchus (Brodsky). Additionally, deep insertion of the bronchial cuff of the DLT would obstruct the upper lobe bronchus (Brodsky). The careful adjustment of the depth and optimal positioning of the DLT using a flexible fiberoptic bronchoscope need a skilled anesthesiologist to reduce the time to DLT intubation. (Charles D. Boucek et al)

There are several methods have been described to predict the proper depth of DLT insertion. Chow et al. documented the validity of the developed formula based on the clavicular-to-carinal distance of trachea and height in 78% of patients studied. Brodsky et al. demonstrated that a height-and-gender-based formula could predict the depth of DLT insertion. Liu et al. reported an accurate depth of DLT insertion in 90% of patients studied measuring the distance between the vocal cord and carina according to the chest CT.

Enrollment: 65 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Underwent thoracic surgery
• Using a left-sided double-lumen tube for one-lung ventilation

Exclusion criteria

• Anticipated or known difficult airway
• Refuse to sign the consent
• Withdraw the consent

Trial design

Primary purpose: Other

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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65 participants in 1 patient group

Predicted depth of insertion

Other group

Description:

The predicted insertion depth of the DLT was calculated using the formula \[0.249 x (BH) 0.916\] before induction of anesthesia using an application on the smartphone

Treatment:

Other: Optimized depth of insertion

Other: Predicted depth of insertion

Other: Adjustment of depth of insertion