From the Guidelines
Nitrous oxide (N2O) anesthesia should be used with caution during splenorenal shunt surgery due to the risk of intraoperative hemorrhage and the potential for N2O to expand air-filled spaces.
Considerations for N2O Anesthesia
- The presence of an unpredictable and often extensive network of esophagogastric varices and other spontaneous pressurized portosystemic shunts around the portal and splenic veins renders intra-abdominal surgeries challenging because of the risk of intraoperative hemorrhage 1.
- Surgical management should be considered only at centers with substantial experience with operating in the setting of pressurized varices, such as liver transplant centers 1.
- The use of N2O anesthesia may not be directly addressed in the provided evidence, but its potential to expand air-filled spaces could exacerbate the risk of intraoperative hemorrhage in patients with portal hypertension.
- Alternative anesthetic techniques should be considered to minimize the risk of complications, and the decision to use N2O anesthesia should be made on a case-by-case basis, taking into account the individual patient's risk factors and the expertise of the surgical team.
- In centers with appropriate experience, surgical shunt creation could be considered, and the anesthetic technique should be tailored to the individual patient's needs 1.
From the FDA Drug Label
WARNING: Administration of Nitrous Oxide may be hazardous or contraindicated For use only by or under the supervision of a licensed practitioner who is experienced in the use and administration of Nitrous Oxide and is familiar with the indications, effects, dosages, methods, and frequency and duration of administration, and with the hazards, contraindications and side effects, and the precautions to be taken.
The FDA drug label does not provide specific considerations for using nitrous oxide (N2O) anesthesia during splenorenal shunt surgery. The label provides general warnings and precautions for the use of nitrous oxide, but does not address its use in this specific surgical context 2.
From the Research
Considerations for Using Nitrous Oxide (N2O) Anesthesia
General Considerations
- Nitrous oxide has been used for over 160 years for the induction and maintenance of general anesthesia 3.
- It is commonly used as part of a technique using other anesthetic gases, intravenous agents, or both 3.
- The use of nitrous oxide may be associated with adverse effects such as low blood oxygen levels, compromised immune system, impaired cognition, postoperative cardiovascular complications, bowel obstruction from distention, and possible respiratory compromise 3.
Specific Considerations for Splenorenal Shunt Surgery
- There is limited evidence specifically addressing the use of nitrous oxide anesthesia during splenorenal shunt surgery.
- However, studies have investigated the use of nitrous oxide in general anesthesia for various surgical procedures, including its effects on postoperative nausea and vomiting (PONV) 4, 5, cardiovascular risk 6, and procedural sedation in pediatric populations 7.
- The decision to use nitrous oxide anesthesia during splenorenal shunt surgery should be based on individual patient factors, such as pre-existing medical conditions and risk of postoperative complications.
Potential Risks and Benefits
- Potential benefits of using nitrous oxide anesthesia include rapid induction and recovery, low cost, and low rate of cardiorespiratory complications 3.
- Potential risks include increased incidence of pulmonary atelectasis, PONV, and cardiovascular complications 3, 4, 6.
- The use of nitrous oxide may be reasonable in patients with pre-existing poor pulmonary function or at high risk of postoperative nausea and vomiting 3.