Preanaesthetic Medication Overview

Preanaesthetic Medication

• Aims to make anesthesia more pleasant and safe
• Used to reduce anxiety and apprehension, using benzodiazepines like diazepam, lorazepam, or midazolam, which have a wide safety margin
• Acts on the limbic system to reduce anxiety
• Prevents vagal bradycardia and reduces salivary secretions with antimuscarinic agents like atropine or glycopyrrolate (glycopyrrolate preferred due to potency, minimal CNS effects, and less tachycardia)
• Relieves pre- and postoperative pain with opioid analgesics (morphine, pethidine, or fentanyl)
• Limitations of opioids include respiratory depression, hypotension, nausea, vomiting, constipation, biliary spasm, and bronchospasm in asthmatics. NSAIDs like diclofenac can also be used
• Anti-emetic effect can be achieved with Metoclopramide, domperidone, or ondansetron
• Prevents acid secretion and stress ulcers with H2-blockers (ranitidine) or proton-pump inhibitors (omeprazole)
• Hastens gastric emptying with prokinetic drugs like metoclopramide or domperidone to prevent aspiration pneumonia

Conscious Sedation

• Level of CNS depression where a patient does not lose consciousness but can communicate and cooperate during the procedure/treatment
• Indications include uncooperative and anxious patients