Comparing Endotracheal Tube Cuff Pressure in Laparoscopic Abdominal Surgery: Saline vs. Air Inflation

A Comparative Analysis of Elevated Endotracheal Tube Cuff Pressure Incidence in Elective Laparoscopic Abdominal Surgery: Saline vs. Air Inflation

In this study, the investigators aim to compare the incidence of cuff pressure increase between endotracheal tubes inflated with air or saline during elective laparoscopic abdominal surgery under general anesthesia with N2O. This prospective observational study will be conducted on 60 patients aged 18-65 with ASA physical status I-II undergoing elective laparoscopic abdominal surgery under general anesthesia. Patients are randomly assigned to two groups: one group has tubes inflated with air (Group H, n=30), while the other group has tubes inflated with saline (Group S, n=30). The cuff pressure is continuously monitored using a pressure transducer attached to the cuff via a three-way tap. Anesthesia maintenance is achieved with sevoflurane and oxygen/N2O (%40/%60) in both groups. The intervention is performed whenever the cuff pressure exceeds 20 mmHg for >30 seconds during the CO2 insufflation of the abdomen, and the pressure is reduced. The number of interventions is recorded as the primary outcome of the study. The cuff pressure is measured before and after insufflation and after the patients are placed in Trendelenburg and reverse Trendelenburg positions.

Study Overview

• Status: Completed
• Conditions: Endotracheal Intubation
• Intervention / Treatment: Procedure: Endotracheal intubation using an endotracheal tube with cuff inflated with saline; Procedure: Endotracheal intubation using an endotracheal tube with cuff inflated with air

Detailed Description

The study is designed as prospective and observational research, which takes place at the Balcalı Hospital of Çukurova University between July 2023 and October 2023. After obtaining written informed consent from the participants and approval from the Çukurova University Clinical Research Ethics Committee (Date: 13.07.2023 and Decision no: 186/10), a total of 60 patients, aged between 18-65, with ASA 1-2 risk category, and expected surgical duration of 30-120 minutes, are included in the study for elective laparoscopic abdominal surgery. The exclusion criteria include neuropsychiatric diseases, muscle diseases, significant cardiovascular and respiratory system diseases, upper respiratory tract infection within the past 14 days, morbid obesity, alcohol or substance dependence, history of bronchospasm, expected difficult intubation, history of tracheostomy, and laryngeal diseases or surgery. After informing the patients about the procedure and obtaining written consent, intravenous (IV) access is established in the preoperative preparation room after an 8-hour fasting period. No premedication is administered. Once the patients are transferred to the operating room, standard anesthesia monitoring including electrocardiography (ECG), non-invasive blood pressure, peripheral oxygen saturation (SpO2), and end-tidal CO2 (EtCO2) are applied. Following 3 minutes of preoxygenation with 100% oxygen, anesthesia induction is performed with a 2 mg/kg IV propofol. TOF (train-of-four) monitor calibration is performed to assess the level of muscle relaxation. Subsequently, 0.6 mg/kg of rocuronium IV is administered for neuromuscular blockade. Fentanyl 1 mcg/kg IV is given during anesthesia induction. Endotracheal intubation (ETI) is performed using a high-volume, low-pressure cuffed endotracheal tube (ETT) with an internal diameter of 7-7.5 mm for female patients and 8-8.5 mm for male patients, once the TOF measurement reaches 0. The intubation procedure is carried out by an experienced anesthesiologist using a Macintosh laryngoscope. According to the randomization table created with a computer program, patients who are randomly selected after endotracheal intubation have the APL valve of the anesthesia machine adjusted to a pressure of 20 cmH20, ensuring that there is no air leakage sound from the patient's mouth during ventilation. The ETT cuffs of patients in Group H are inflated with air, while those in Group S are inflated with saline. The cuff pressure is continuously monitored using a pressure transducer connected to the cuff balloon through a three-way stopcock. The transducer set is filled with saline to ensure no air is present. It is connected to a three-way stopcock at the desired measurement point level. All connections are taped to prevent disconnection and leaks, and a "For Respiratory Use Only" label is affixed to enhance patient safety. The pressure calibration on the patient monitor is adjusted according to the sternal notch level of the patient, and the cuff pressure value is measured in mmHg. After ETT placement, ventilation of the patient is set as volume-controlled ventilation with a tidal volume of 6-8 ml/kg, frequency of 10-12/min, and EtCO2 of 35-45 mmHg. An esophageal temperature measurement probe is placed to monitor body temperature. Maintenance of anesthesia for all patients is achieved using a gas mixture of sevoflurane and oxygen/nitrous oxide (40%/60%). When the TOF value is 2 during the maintenance of muscle relaxation, rocuronium 0.15 mg/kg is administered intravenously. Nasogastric tubes are placed in all patients. 45 minutes before the completion of the surgery, tramadol 2 mg/kg IV and paracetamol 1 g IV are administered to provide postoperative analgesia. In cases where the intracuff pressure exceeds 20 mmHg for more than 30 seconds during CO2 insufflation, intervention is performed using a three-way stopcock and syringe to reduce the pressure to 18 mmHg, and the number of interventions is recorded. The highest intracuff pressure, ventilator peak pressure, plateau pressure, and PEEP are recorded every 15 minutes during the first minute after CO2 insufflation. In cases where the intracuff pressure exceeds 20 mmHg for more than 30 seconds during this period, intervention is performed to reduce the pressure to 18 mmHg using a three-way stopcock and syringe. The number of interventions is recorded. Additionally, the intracuff pressures before and after the patients are placed in the reverse Trendelenburg and Trendelenburg positions are recorded. At the end of the surgery, 0.04 mg/kg neostigmine IV and 0.01 mg/kg atropine IV are administered to reverse the effects of muscle relaxation. The patients are extubated when they respond adequately to verbal stimuli and the train-of-four (TOF) value is 90% or above. Once sufficient muscle strength and airway safety are ensured, the patients are transferred from the operating room to the postoperative recovery unit.

In our pilot study, we observed that the total number of interventions 30 minutes after insufflation differed significantly between the saline group (mean = 2.31) and the air group (mean = 4.01), with a standard deviation of 1.68. To ensure a 95% power and a significance level of 0.05%, we determined that a sample size of 27 patients per group (total of 57 patients) was necessary. To account for potential data loss, we included 60 patients in the study.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey
  • Adana, Turkey, 01130
    • Department of Anesthesiology, Cukurova University Faculty of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• aged 18-65,
• American Society of Anesthesiologists physical status 1 or 2
• Expected surgery time of 30-120 minutes,
• Scheduled for elective laparoscopic abdominal surgery

Exclusion Criteria:

• neuropsychiatric disease
• muscle disease
• serious cardiovascular and respiratory system disease
• upper respiratory tract infection in the last 14 days
• morbid obesity
• alcohol or substance addiction
• history of bronchospasm
• expectation of difficult intubation
• history of tracheostomy
• history of laryngeal disease or surgery.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Saline Group; Anesthesia machine's APL valve will be adjusted to a pressure of 20 cmH20, and during ventilation with a balloon, the endotracheal tube cuffs will be inflated with saline in such a way that there will be no leakage sound from the patient's mouth.	Procedure: Endotracheal intubation using an endotracheal tube with cuff inflated with saline; After endotracheal intubation, the endotracheal tube cuff is inflated with saline
Placebo Comparator: Air Group; Anesthesia machine's APL valve will be adjusted to a pressure of 20 cmH20, and during ventilation with a balloon, the endotracheal tube cuffs will be inflated with air in such a way that there will be no leakage sound from the patient's mouth.	Procedure: Endotracheal intubation using an endotracheal tube with cuff inflated with air; After endotracheal intubation, the endotracheal tube cuff is inflated with air

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The number of intervention	The number of interventions required to correct intracuff pressure	15 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Peak Airway pressure	Peak airway pressure during the intraoperative period is measured in cmH2O.	15 minutes

Collaborators and Investigators

• Sponsor: Cukurova University

Publications and helpful links

General Publications

• Armstrong J, Jenner P, Poulose S, Moppett IK. The effect of saline versus air for cuff inflation on the incidence of high intra-cuff pressure in paediatric MicroCuff(R) tracheal tubes: a randomised controlled trial. Anaesthesia. 2021 Nov;76(11):1504-1510. doi: 10.1111/anae.15493. Epub 2021 Apr 23.

Study record dates

Study Major Dates

• Study Start (Actual): September 27, 2023
• Primary Completion (Actual): December 12, 2023
• Study Completion (Actual): December 12, 2023

Study Registration Dates

• First Submitted: September 26, 2023
• First Submitted That Met QC Criteria: October 16, 2023
• First Posted (Actual): October 18, 2023

Study Record Updates

• Last Update Posted (Estimated): December 13, 2023
• Last Update Submitted That Met QC Criteria: December 12, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: ETTSVA

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No