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What is a Spinal Anesthetic?

Spinal Anesthetics are commonly used as a form of Anesthesia for Surgery. The other common forms of Anesthesia are "General Anesthetics", "MAC Anesthetics", and "Local Anesthetics".

In a Spinal Anesthetic, Local Anesthetic medications are injected directly into the Spinal Fluid to anesthetize specific Spinal Nerves which are bathed by the Spinal Fluid. This results in a "numb area" of the part of the Body where Surgery is planned. For a General Anesthetic, medications are injected through an IV (intravenous line) to put a patient to sleep completely (unconscious). After that, a breathing machine (ventilator) will breathe for the patient. In a Spinal Anesthetic, patient usually do receive relaxing medications through an IV, however not for the purpose of putting the patient to sleep completely. A "MAC Anesthetic" (Monitored Anesthesia Care) relies on relaxing medications which are also injected through an IV. However in a MAC Anesthetic, patients may be unconscious, but continue to breathe on their own. A "Local Anesthetic" means that anesthetic medication is injected under the Skin to anesthetize a specific area of the Body.

Now that we have looked at the Anatomy, lets talk more about how a Spinal Anesthetic is done and how it works. The Anesthetist usually gives the patient a choice of a Spinal Anesthetic if they believe it is a good option for the type of planned Surgery. Spinal Anesthetics are usually only an option for Surgery below the bottom of our Breast Bone (abdomen, pelvis, rectum, legs, feet, etc.).

If a Spinal is an option, the Anesthetist typically informs the patient about "Risks and Benefits" of the Spinal compared to other Anesthetics (General, MAC, Local). The main risks are twofold: 1. The Spinal may not be an adequate Anesthetic for the Surgery, in which case a General Anesthetic may have to be given. 2. A patient receiving a Spinal Anesthetic may get a "Spinal Headache" afterwards. This type of headache results for the small hole the Spinal Needle leaves in the lining of the Spinal Fluid (dura). This small hole sometimes allow Spinal Fluid to leak which can result in a headache and nausea amongst other symptoms. Other risks to exist (bleeding, infection, etc.) but are less common.

The first step in performing a Spinal is for the patient to sit up or lie on their side and bend forward or curl up. This position separates the Vertebrae in the back and creates a larger opening for the Spinal Needle. After the skin is anesthetized, a Spinal Needle is placed through the Skin and advanced deeper through the Spinal Ligaments. Once the Needle has passed through these Ligaments, it will encounter the Spinal Fluid. This fluid is the target of the Spinal Anesthetic.

After the Spinal Needle is placed in the Spinal Fluid, anesthetic medication can be injected. The type of medication often depends on the type and length of Surgery. The amount of medication typically depends on the patient size and the length of Surgery. A commonly used Anesthetic is Bupivacaine (Marcaine). Sometimes, narcotic pain medications are added to the Anesthetic. Spinal Anesthetics can last for hours, depending on the type and amount of Anesthetic injected.

Spinal Anesthetics are generally safe and effective. However, they are the patients choice of Anesthetic. Some patients do not like the idea of having a Spinal Injection for fear of having back pain afterwards. Others do not like the idea of having a feeling of paralysis in their abdomen and legs during Surgery and a period if time afterwards. It is important to discuss all the pros and cons of the Anesthetic with the Anesthetist.