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

Efficacy of Height-Based Formula to Predict Insertion Depth of Left-Sided Double Lumen Tube. A Prospective Observational Study

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04329416
Enrollment
65
Registered
2020-04-01
Start date
2019-05-07
Completion date
2020-03-15
Last updated
2020-04-01

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Left-sided Double Lumen Tube, One Lung Ventilation, Thoracic Surgery

Brief summary

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.

Detailed 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.

Interventions

OTHERPredicted depth of insertion

A left-sided double-lumen tube was introduced beyond the vocal cords when the train-of-four stimulation of the ulnar nerve revealed 1 or 2 twitches, the stylet was removed, the double-lumen tube was rotated 90° counterclockwise and then advanced blindly to the predicted depth of insertion.

OTHEROptimized depth of insertion

The optimal position of the double-lumen tube, defined as the inflated endobronchial cuff is placed in the left main bronchus just below the carina without herniation, which was confirmed using a flexible bronchoscope in both supine and lateral decubitus positions.

OTHERAdjustment of depth of insertion

If the endobronchial cuff was placed too deeply or too proximal, subsequently, the double-lumen tube was withdrawn or advanced, respectively, using the flexible bronchoscope until the optimum position of the double-lumen tube was achieved.

Sponsors

King Saud University
CollaboratorOTHER
Imam Abdulrahman Bin Faisal University
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE

Intervention model description

A prospective observational single-center open-label study

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

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

Design outcomes

Primary

MeasureTime frameDescription
The rate of optimum position of the double-lumen tubefor 15 minutes after double-lumen tube insertionThe rate of optimum position of a left-sided DLT without further adjustments, defined as the inflated endobronchial cuff is placed in the left main bronchus just below the carina without herniation

Secondary

MeasureTime frameDescription
The initial depth of insertionfor 15 minutes after double-lumen tube insertionThe initial depth of insertion, was measured using the external centimeter markings on the DLT's lumen at the level of incisors
Position of the double-lumen tube with the flexible bronchoscopefor 15 minutes after double-lumen tube insertionThe position of the DLT with the flexible bronchoscope would be rated either (1) optimally placed, (2) too far out, or (3) too far in
The need for bronchoscopic adjustmentsfor 15 minutes after double-lumen tube insertionIf the endobronchial cuff was placed too deeply or too proximal, subsequently, the DLT was withdrawn or advanced, respectively, using the flexible bronchoscope until the optimum position of the DLT was achieved. The optimizing maneuvers were recorded
The final correct depth of insertionfor 15 minutes after double-lumen tube insertionthe final correct depth of insertion, defined as the distance from the distal opening of the bronchial lumen to the corner of the mouth, was measured with a flexible bronchoscope passing through the bronchial lume
Time to final correct double-lumen tube positioningfor 25 minutes after double-lumen tube insertionTime to final correct DLT positioning from time of laryngoscopy was recorded
The calculated predicted depth of insertionimmediately before induction of general anesthesiaThe predicted insertion depth of the DLT was calculated using the formula \[0.249 x (BH) 0.916\] using an application an application on the smart phone
Changes in mean arterial blood pressurefor 25 minutes after double-lumen tube insertionPostintubation changes in mean arterial blood pressure was recorded
Changes in peripheral oxygen saturationfor 25 minutes after double-lumen tube insertionPostintubation changes in peripheral oxygen saturation was recorded
Degree of lung collapsefor 30 minutes after start of surgerydegree of lung collapse was rated as excellent, good, poor, or very poor
The incidence of soreness of throatfor 24 hours after start of surgeryPatients were asked about the occurrence and severity of postoperative sore throat
The incidence of mucosal injuryfor 40 minutes after double-lumen tube insertionThe incidence of mucosal injury using the flexible bronchoscope was reported after intubation using the double-lumen tube
Changes in heart ratefor 25 minutes after double-lumen tube insertionPostintubation changes in heart rate was recorded

Countries

Saudi Arabia

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026