Ultrasound and CT guided measurement of cricoid cartilage diameter may effectively determine size of DLT in thoracic surgery: Study

Accurate airway management is crucial in thoracic surgeries, especially those involving lung resections. Achieving ideal lung isolation is vital for patient safety and surgical effectiveness. While double-lumen tubes (DLTs) are now the standard for lung isolation, the task of selecting the right DLT size remains difficult. Recent research paper investigates the use of ultrasonography (USG) and computed tomography (CT) in measuring cricoid cartilage diameter for objective double-lumen tube (DLT) sizing in thoracic surgeries. The study involves a randomized comparative trial of 120 adult patients undergoing thoracic surgery, grouped into USG, CT, and conventional DLT size determination based on height and gender. The primary outcomes were appropriateness of DLT size, degree of lung collapse, and sore throat. The results indicated improved accuracy of DLT sizing based on cricoid cartilage diameter, with significantly lower rates of inappropriate sizes and better outcomes in lung collapse and sore throat in the USG and CT groups compared to the conventional group.

Methodology and Tool Exploration

The research discusses the challenges of selecting the correct DLT size for thoracic surgeries, a vital aspect of airway management. Factors such as patient height, gender, tracheal diameter, left main bronchial (LMB) diameter, and cricoid cartilage transverse diameter play significant roles in DLT size selection. Ultrasonography and computed tomography are explored as tools for accurately measuring the cricoid cartilage diameter, with advantages such as quick, convenient, safe, and radiation-free assessment of airway anatomy. The study is based on a single-center trial with 120 adult patients, and the primary inclusion criteria were patients undergoing thoracic surgery requiring single-lung ventilation, excluding those with anticipated difficult airways. The results showed that DLT sizing based on cricoid cartilage diameter improved accuracy, with significantly lower rates of inappropriate sizes in the USG and CT groups compared to the conventional group. Lung collapse was also better in the USG and CT groups, with significantly lower rates of sore throat in these groups compared to the conventional group. The study underscores the superiority of USG and CT in DLT measurement over the conventional group, and the compatibility of USG with real-time, non-invasive, and cost-effective measurements. The paper acknowledges the limitations of the study, such as being a single-center trial and not examining other anatomical parameters that may influence DLT size selection. However, the study's results indicate that ultrasonography and computed tomography-guided measurement of cricoid cartilage diameter is a reliable and effective method compared to the conventional method for determining the size of a double-lumen tube in thoracic surgery.

Key Points

- The study focused on the use of ultrasonography (USG) and computed tomography (CT) to measure cricoid cartilage diameter for objective double-lumen tube (DLT) sizing in thoracic surgeries.

- The research involved a randomized comparative trial of 120 adult patients undergoing thoracic surgery, categorized into USG, CT, and conventional DLT size determination based on height and gender, with the primary outcomes being appropriateness of DLT size, degree of lung collapse, and sore throat.

- The article discussed the callenges of selecting the correct DLT size for thoracic surgeries, considering factors such as patient height, gender, tracheal diameter, left main bronchial (LMB) diameter, and cricoid cartilage transverse diameter.

- Ultrasonography and computed tomography were explored as tools for accurately measuring the cricoid cartilage diameter, with advantages including quick, convenient, safe, and radiation-free assessment of airway anatomy. - The results showed improved accuracy of DLT sizing based on cricoid cartilage diameter, with significantly lower rates of inappropriate sizes and better outcomes in lung collapse and sore throat in the USG and CT groups compared to the conventional group.

- The study acknowledged limitations such as being a single-center trial and not examining other anatomical parameters that may influence DLT size selection, but concluded that ultrasonography and computed tomography-guided measurement of cricoid cartilage diameter is a reliable and effective method for determining the size of a double-lumen tube in thoracic surgery.

Reference -

Mathew RM, Gautam S, Raman R, Rai A, Srivastava VK, Singh MK. Evaluating the precision of ultrasound versus computed tomography‑guided measurement of cricoid cartilage diameter for double‑lumen tube selection in thoracic surgery: A randomised comparative study. Indian J Anaesth 2024;68:896‑901