WHAT IS PREMEDICATION?
Surgery is a delicate procedure, and anesthesia is an integral part of it. Surgery in its different forms is invasive to several degrees, and painful. Cutting into the body would normally cause extreme pain that could send the patient into shock, and maybe even death
Anesthesia modulates that pain by muting, reducing and even removing it entirely, putting the patient in a more relaxed state of unconsciousness so that the surgery can be carried out without hitches.
Pre-medication is medication given to act synergistically with the anesthetic agents, usually given before the anesthetic is administered. It prepares the patient for anesthesia and reduces the risk of side-effect from the use of anesthetic agents.
Pre-medication is usually given between 1-3 hours before anesthesia is administered. The practice is fading because of increasingly specific and less risky anesthetic agents, short recovery time (like in outpatient surgery) and personal preference by patients. The choice of medication will depend on the patient’s medical history, the type of anesthesia to be used in surgery, and the patient’s peculiar needs.
WHY IS PREMEDICATION GIVEN?
- As an agent to optimize and enhance anesthesia
- To relieve anxiety and stress
- To create optimal conditions for surgery
- To ease anesthesia-induced nausea and vomiting
- To reduce the risk of vagal reaction to anesthesia, especially when the patient is intubated.
- To relieve acute, short-term pain before surgery.
- To induce gastric emptying and prevent regurgitation during surgery.
TYPES OF PRE-MEDICATION
Analgesics: Non-steroidal anti-inflammatory agents (NSAIDS) and opioids can be given for patient’s relaxation and comfort. These are given with caution, especially when administering opioids, to reduce the risk of respiratory suppression later in surgery. Analgesics are given to relieve acute pain and make the patient more comfortable before surgery. They can, however, inducenausea and cause vomiting. Their benefits should be carefully weighed against the potential risks.
Anti-emetics: Emesis (vomiting) is an unpleasant side-effect of some anesthetic agents, particularly antihistamines and hyoscine. An anti-emetic can be given to the patient to prevent this side effect and to induce gastric emptying when it is necessary.
When the surgery involves a high risk or regurgitation, Anti-emetics help to reduce the risk and prevent complications.
Anti-vagal: Some anesthetic agents can induce bradycardia (abnormally slow heartbeat), especially ketamines. In this case, an anti-vagal compound like hyoscine can be given to prevent bradycardia action after administration of the anesthetic agent.Hyoscine also reduces salivation, which could interfere with intubation and cause the patient to choke. It can also induce amnesia.
The side effect of dry mouth though could become a problem for the patient as the mouth needs lubrication to prevent injuries by intubation.
Sedatives: Before benzodiazepines or mild opioids are given to patients who are anxious about having surgery, they should be reassured and put at ease first. Sedatives should be given as a last resort.
To induce amnesia: A deeper state of amnesia will mean that the patient will not need a high dose of anesthetics. This can be achieved by pre-medication, putting the patient deeper under and reducing the attendant risks.