Optimal Depth for Esophageal Stethoscope

NCT ID: NCT05552092

Last Updated: 2024-08-22

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 40 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-11-26
• Study Completion Date: 2025-08-31

Brief Summary

The purpose of the present study was to evaluate the optimal insertion depth of an esophageal stethoscope with a thermistor for core temperature monitoring.

Detailed Description

Monitoring core temperature is crucial for maintaining normothermia during general anesthesia. During anesthesia, an esophageal stethoscope with a thermistor for monitoring esophageal temperature is frequently used.

There are several researches on the depth or position of the esophageal stethoscopes, but there is only limited information (known as about 40-45 cm or T8-T9).

The purpose of the present study was to evaluate the optimal insertion depth of an esophageal stethoscope with a thermistor for core temperature monitoring.

Conditions

Surgery

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: OTHER
• Blinding Strategy: NONE

Study Groups

Experimental

The patients with ASA class 1-2 (20-65 years old) who are undergoing elective surgery with supine or lithotomy position, without position change, scheduled to last more than 90 min.

Group Type: EXPERIMENTAL

Esophageal temperature monitoring according to the depth

Intervention Type: DEVICE

Core temperatures will be measured with a tympanic thermometer as a reference. When the tympanic membrane (TM) temperature is constant after measuring three consecutive times at 10 seconds intervals, the temperature will be assumed as the core body temperature.

Initially, the esophageal stethoscope (ES) will be inserted to a depth of 45 cm from the incisor. After 30 minutes of monitoring, when the changes in the body temperatures stabilized, initial temperatures of the TM and ES thermistor will be assessed.

After 5 minutes, ES will be taken out 2 cm back, and the temperatures of each site will be measured when the temperature change of the ES thermistor stabilized below 0.1°C. Eventually, the depth of ES will be changed from 45 to 27 cm with a 2 cm interval, and the temperature at each position will be measured.

Anatomical landmark

Intervention Type: OTHER

For the further evaluation of the optimal insertion depth of GDT, anatomical landmarks such as distance from the cricoid cartilage to the carina (CCD) and distance from the carina to the intervertebral disc between T8 and T9 (CDD) will be measured using an electronic caliper on a preoperative chest X-ray.

Interventions

Esophageal temperature monitoring according to the depth

Core temperatures will be measured with a tympanic thermometer as a reference. When the tympanic membrane (TM) temperature is constant after measuring three consecutive times at 10 seconds intervals, the temperature will be assumed as the core body temperature.

Initially, the esophageal stethoscope (ES) will be inserted to a depth of 45 cm from the incisor. After 30 minutes of monitoring, when the changes in the body temperatures stabilized, initial temperatures of the TM and ES thermistor will be assessed.

After 5 minutes, ES will be taken out 2 cm back, and the temperatures of each site will be measured when the temperature change of the ES thermistor stabilized below 0.1°C. Eventually, the depth of ES will be changed from 45 to 27 cm with a 2 cm interval, and the temperature at each position will be measured.

Intervention Type: DEVICE

Anatomical landmark

For the further evaluation of the optimal insertion depth of GDT, anatomical landmarks such as distance from the cricoid cartilage to the carina (CCD) and distance from the carina to the intervertebral disc between T8 and T9 (CDD) will be measured using an electronic caliper on a preoperative chest X-ray.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• The patients with ASA class 1-2 (20-65 years old) who are undergoing elective surgery with supine or lithotomy position, without position change scheduled to last more than 90 min.

Exclusion Criteria

• anatomical abnormality with the upper airway
• risks of a difficult airway
• abnormal central anatomical structures such as airway, diaphragm, or spine on the chest X-ray
• history of disease or surgery on the stomach or esophagus
• risks of bleeding or coagulopathy on the preoperative laboratory results
• obese patients with BMI over 30
• contraindication to insertion of ES for the surgery
• who did not take a standing chest PA X-ray before surgery
• position change during the surgery
• open chest surgery

• Minimum Eligible Age: 20 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Chosun University Hospital

OTHER

Sponsor Role: lead

Responsible Party

Ki Tae Jung

Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Ki Tae Jun, M.D., Ph.D.

Role: STUDY_DIRECTOR

Chosun University Hospital

Locations

Chosun University Hospital

Gwangju, , South Korea

Countries

South Korea

References

Wang M, Singh A, Qureshi H, Leone A, Mascha EJ, Sessler DI. Optimal Depth for Nasopharyngeal Temperature Probe Positioning. Anesth Analg. 2016 May;122(5):1434-8. doi: 10.1213/ANE.0000000000001213.

Reference Type: RESULT

PMID: 26974019 (View on PubMed)

Other Identifiers

ET_Position

Identifier Type: -

Identifier Source: org_study_id