From the Guidelines
The management algorithm for aspiration under anesthesia begins with immediate recognition and positioning the patient with the head down in a lateral position to allow drainage of aspirated material, as recommended by the most recent guidelines. The incidence of pulmonary aspiration is low, with a reported incidence of 1 in 7000, and morbidity and deaths are very much lower, at 1 in 1700 and 1 in 100,000, respectively 1.
Key Steps in Management
- Immediately administer 100% oxygen and perform tracheal suctioning to remove visible material.
- Intubate the patient if not already done to secure the airway and provide positive pressure ventilation.
- Bronchoscopy should be considered for removal of particulate matter.
- Monitor oxygen saturation, respiratory parameters, and obtain a chest X-ray to assess the extent of aspiration.
- Bronchodilators such as albuterol (2.5-5 mg nebulized) should be administered for bronchospasm.
- Corticosteroids are not routinely recommended unless there is significant bronchospasm.
- Prophylactic antibiotics are generally not indicated unless signs of infection develop.
- If bacterial pneumonia is suspected, empiric antibiotics covering oral flora should be initiated (such as ampicillin-sulbactam 3g IV every 6 hours or clindamycin 600mg IV every 8 hours).
Prevention
Prevention through proper fasting guidelines, rapid sequence induction in high-risk patients, and use of prokinetics or antacids in emergency situations remains the best approach to managing this potentially serious complication, as the fear of aspiration should not lead to excessive pre-operative food and fluid restriction 1. The management of tracheal extubation is also crucial, as it is a critical step during emergence from general anesthesia, and guidelines for the management of tracheal extubation in adult peri-operative practice have been established 1. However, the management of aspiration under anesthesia should prioritize the patient's safety and well-being, and the algorithm should be tailored to the individual patient's needs and circumstances.
From the Research
Aspiration Under Anaesthetic Algorithm
The management algorithm for aspiration under anesthesia involves several key steps to minimize the risk of regurgitation and aspiration.
- Control of gastric contents through preoperative starvation is a universally accepted method 2.
- Application of cricoid pressure and control of the airways are also crucial in preventing aspiration 2.
- In patients with a high risk of aspiration, rapid sequence induction and intubation (RSI) should be performed, with optimal drug pre-treatment using antacids, proton pump inhibitors, or H2 blockers 3.
- Consistent pre-oxygenation with an FIO2 of 1.0 and an oxygen flow > 10 l/min using a completely sealing respiratory mask with capnography should take 3-5 minutes 3.
- Fast enough deep anesthesia and muscle relaxation can be achieved by a combination of opioid, hypnotic, and muscle relaxation, with options including propofol, thiopental, etomidate, ketamine, and rocuronium or succinylcholine as muscle relaxants 3.
Risk Factors for Aspiration
Several factors contribute to the likelihood of aspiration, including:
- Urgency of surgery
- Airways problems
- Inadequate depth of anesthesia
- Use of the lithotomy position
- Gastrointestinal problems
- Depressed consciousness
- Increased severity of illness
- Obesity 2.
- A gastric content with a pH less than 2.5 and a gastric volume of 0.4 ml kg-1 also predispose to aspiration pneumonia 2.
Management of Aspiration
In case of aspiration, intensive medical monitoring and fiber-optic bronchoscopy should be performed, depending on the degree of severity, and an X-ray thorax image or a CT scan should be performed if symptoms arise 3.
- Emergency extracorporeal membrane oxygenation may be used to treat massive aspiration during anesthesia induction 4.
- Aspiration pneumonitis resulting from positional change during procedural sedation can be managed without oral endotracheal intubation, with careful monitoring and supportive care 5.
- Parenteral and enteral antacids, such as omeprazole and sodium citrate, can be used as premedication to prevent regurgitation and aspiration in urgent surgery 6.