Question

Opioid free anaesthesia.

Hint:

Opioid-free anaesthesia can reduce opioid-related side effects and improve recovery times, but requires careful management of alternative analgesics.

Answer 1

Step 1: Introduction to Opioid-Free Anaesthesia (OF.
Opioid-free anaesthesia (OF refers to a technique of anaesthesia where opioids (such as morphine, fentanyl, and remifentanil) are avoided in the perioperative period. Instead, the anaesthetic plan focuses on the use of alternative agents to achieve analgesia, hypnosis, and muscle relaxation. This approach aims to reduce the side effects and complications associated with opioids, such as nausea, vomiting, respiratory depression, and postoperative ileus.
Step 2: Components of Opioid-Free Anaesthesia.
(1) General Anaesthesia Without Opioids:
- Inhaled anaesthetics (e.g., sevoflurane, desflurane) or IV anaesthetics (e.g., propofol) are used for induction and maintenance of anaesthesia.
- The analgesic effect is achieved using non-opioid drugs, including NSAIDs (non-steroidal anti-inflammatory drugs), acetaminophen, local anaesthetics, and ketamine.
(2) Use of Ketamine:
- Ketamine, an NMDA receptor antagonist, is often used in opioid-free anaesthesia for its analgesic and amnesic properties. It provides significant pain relief and can prevent central sensitization, which is important in major surgeries.
- Ketamine is also known for its cardioprotective and neuroprotective effects, making it particularly useful in patients with cardiovascular instability or neurological conditions.
(3) Alpha-2 Agonists (Dexmedetomidine):
- Dexmedetomidine, an alpha-2 adrenergic agonist, is used to achieve sedation and analgesia without respiratory depression. It has a sympatholytic effect, reducing blood pressure and heart rate, and it also provides analgesic effects by inhibiting norepinephrine release in the central nervous system.
(4) Regional Anaesthesia:
- Techniques such as epidural anaesthesia, spinal anaesthesia, or peripheral nerve blocks can provide effective pain relief in major surgeries, reducing or eliminating the need for opioids.
Step 3: Advantages of Opioid-Free Anaesthesia.
(1) Reduced Postoperative Nausea and Vomiting (PONV):
- By avoiding opioids, OFA significantly reduces the incidence of nausea and vomiting, which are common opioid-related side effects.
(2) Faster Recovery:
- Opioid-free anaesthesia is associated with faster recovery times, particularly in terms of gastrointestinal function, as opioids are known to cause postoperative ileus.
(3) Improved Respiratory Function:
- Avoiding opioids can reduce the risk of respiratory depression, leading to better postoperative oxygenation and a lower incidence of respiratory complications.
(4) Decreased Risk of Opioid Dependence:
- Reducing opioid use in the perioperative period may help mitigate the risk of opioid dependence or misuse, especially in patients with a history of substance abuse.
Step 4: Challenges of Opioid-Free Anaesthesia.
(1) Need for Alternative Analgesics:
- Effective analgesia may be difficult to achieve in some cases without opioids, requiring higher doses of non-opioid analgesics or the use of additional agents such as ketamine or local anaesthetics.
(2) Increased Cost and Complexity:
- The use of alternative agents like ketamine and dexmedetomidine may increase costs and complexity of anaesthesia management.