Effects of Different Inhaled Oxygen Concentrations on Lung Function in Older Patients After Laparoscopic Gastrointestinal Surgery Under General Anesthesia

China Medical University, China

Status and phase: Enrolling; Phase 4

Conditions: Oxygenation Index

Treatments: Drug: 80% Oxygen; Drug: 40% Oxygen

Study type: Interventional

Funder types: Other

Identifiers

NCT06359106

2024.3.1

Details and patient eligibility

About

This was a multicenter, prospective, parallel-grouping, randomized controlled clinical study comparing low FiO2 (40%) and high FiO2 (80%) levels in older patients undergoing laparoscopic gastrointestinal surgery.

Full description

This was a multicenter, prospective, parallel-grouping, randomized controlled clinical study comparing low FiO2 (40%) and high FiO2 (80%) levels in older patients undergoing laparoscopic gastrointestinal surgery. the investigators planned to enroll 1098 subjects aged > 65 years for laparoscopic gastrointestinal surgery at 19 clinical trial centers in China, randomized in a 1:1 ratio, to use two inhaled oxygen concentrations during surgery. All patients will be performed via the lung-protective ventilation strategy. The respiratory parameters are VT: 6-8ml/kg, PEEP: 6-8 cmh2O, RR: 1:2, and respiratory rate will be adjusted by maintaining a partial pressure of carbon dioxide at 35-45 mmHg. Manual lung recruitment maneuvers will be performed after tracheal intubation and before tracheal extubation. The main outcome measure was the oxygenation index on the postoperative 48h. The secondary outcome measures were the 7-day postoperative pulmonary complications and 30-day mortality rates et al.

Enrollment: 1,176 estimated patients

Sex: All

Ages: 65+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age not less than 65 years
• American Society of Anesthesiologists grades I-III
• No history of drug allergies or abnormal anesthesia.
• The duration of mechanical ventilation was expected to be more than 2 hours.
• Laparoscopic Gastrointestinal Surgery
• The preoperative oxygen saturation was not less than 94%.
• The patients will be planned to extubate in the operating room.

Exclusion criteria

• History of acute lung injury or acute respiratory distress syndrome (ARDS) within 3 months.
• Cardiac function Class IV (New York Heart Association classification)
• Chronic renal failure (renal cell filtration rate <30 ml min-11.73/m2), severe liver disease
• Patients with blurred consciousness and cognitive dysfunction
• Severe coagulation dysfunction.
• Without preoperative oxygen inhalation, blood oxygen level <94%, and severe pulmonary dysfunction
• Patients with endotracheal tubes were admitted to the intensive care unit (ICU) after surgery.
• Body mass index (BMI) >30kg/m2
• Inability to complete the study

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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1,176 participants in 2 patient groups, including a placebo group

Control: 80% Oxygen

Placebo Comparator group

Description:

Before anesthesia induction, the participants inhaled 100% oxygen through the mask for 3 minutes. After successful anesthesia induction, the fraction of inspired oxygen (FiO2) will be adjusted to 80%, and the total gas flow rate will be set at 2L/minute. All patients will receive treatment through the lung-protective ventilation strategy. The respiratory parameters are VT: 6-8mL/kg, positive end-expiratory pressure (PEEP), 6-8 cmH2O; RR: 1:2, and respiratory rate will be adjusted by maintaining a partial pressure of carbon dioxide at 35-45 mmHg. Manual lung recruitment maneuvers will be performed after tracheal intubation and before tracheal extubation. Blood will be collected for blood gas analysis within 48 hours after surgery.

Treatment:

Drug: 80% Oxygen

Experimental: 40% Oxygen

Experimental group

Description:

Before anesthesia induction, the participants inhaled 100% oxygen through the mask for 3 minutes. After successful anesthesia induction, FiO2 will be adjusted to 40%, and the total gas flow rate will be set at 2L/minute. All patients will receive treatment through the lung-protective ventilation strategy. The respiratory parameters are VT: 6-8mL/kg, positive end-expiratory pressure (PEEP), 6-8 cmH2O; RR: 1:2, and respiratory rate will be adjusted by maintaining a partial pressure of carbon dioxide at 35-45 mmHg. Manual lung recruitment maneuvers will be performed after tracheal intubation and before tracheal extubation. However, when intraoperative oxygen saturation is less than 94%, the manual lung recruitment maneuver will also be performed. Patients should transfer to 80% Oxygen group if intraoperative oxygen saturation less than 85%.Blood will be collected for blood gas analysis within 48 hours after surgery.

Treatment:

Drug: 40% Oxygen