THE ADVANTAGES OF INTRAVENOUS (EVIPAN) ANAESTHESIA IN OPHTHALMIC SURGERY

Intravenous anesthetics are drugs administered parenterally to induce anesthesia or sedation. Propofol is a widely used agent formulated as a 1% emulsion in soybean oil, glycerol, and egg phosphatide. It induces rapid anesthesia primarily due to its rapid distribution from the bloodstream to target tissues and is metabolized in the liver. However, it can cause significant pain on injection and hypertriglyceridemia. Fospropofol, a water-based prodrug of propofol, lacks these adverse effects.

Intravenous regional anesthesia or the Bier block technique is used to anesthetize a specific limb or extremity. It uses exsanguinated or blood-drained vessels to transport local anesthetics or LAs to the peripheral nerve trunks. Lidocaine without vasoconstrictors like epinephrine is most commonly used for this technique. Other drugs used are prilocaine, ropivacaine, and chloroprocaine. Bupivacaine is not recommended for this technique due to its high cardiac toxicity.
One of the advantages of...

Epidural anesthetics are administered in the fat-filled epidural space, the outermost part of the spinal canal. This technique is commonly employed for pain management and anesthesia during lower abdomen and pelvis surgeries or labor and delivery.
Since epidural anesthetics can be infused through an epidural catheter, all types of drugs, including short-acting ones, can be administered. Chloroprocaine and lidocaine are examples of short and long-duration anesthetics, respectively. Bupivacaine...

Ophthalmic drug delivery faces major limitations due to poor absorption across the corneal membrane. This process is primarily driven by diffusion and is influenced by two main factors: the physicochemical properties of the drug and tear drainage. Most ophthalmic drugs, such as pilocarpine, epinephrine, atropine, and local anesthetics, are weak bases. They are typically formulated at an acidic pH to enhance chemical stability. However, this leads to high ionization, reducing their ability to...

Anesthesia is a medical procedure that uses drugs for CNS suppression to enable painless surgeries and procedures. The selection of anesthetics is influenced by their pharmacokinetic properties, side effects, and patient characteristics. Various types of anesthesia include general, local, regional, spinal, and inhalational.
General anesthesia induces unconsciousness in the whole body, while the others target specific areas or sensations. It is administered to minimize adverse effects, maintain...

Depending on the target organ, local anesthetics (LAs) can be administered via various routes. In surface anesthesia, LAs are applied directly to the surface of the skin or mucous membranes. It is widely used for topical skin numbing before venipuncture or minor surgical procedures. Commonly used surface local anesthetics are lidocaine or benzocaine sprays or creams. Surface anesthesia occurs within 5 minutes and lasts for about 60 minutes. One of the main disadvantages of topical anesthesia is...