Combination Anesthesia

Using a combination of spinal and general anesthesia can take advantage of the benefits of each and limit the side effects. If a spinal anesthetic is used in addition to a general anesthetic, the amount of general anesthesia required is quite small, because the patient is already numb from the waist down and not receiving any stimulation from the surgery. Therefore, the patient can receive the benefits of spinal anesthesia, such as decreased blood loss, decreased chance of blood clot formation in the deep veins, and post-operative pain control, as well as achieve the safety benefits of general anesthesia, i.e., maintaining adequate ventilation and oxygenation. After the procedure, the patient that has had a combined anesthetic usually wakes up quickly with less of the "hangover" effects of general anesthesia. There is also less irritation to the lungs from the anesthetic agents, resulting in less chance of breathing difficulties and pneumonia afterwards.

There is one increased risk of combined anesthesia and that is an increased chance of having a transient drop in blood pressure. This occurs because of the pooling of the blood in the deep veins caused by the spinal anesthetic, combined with the usual transient drop in blood pressure on induction of general anesthesia. This can usually be avoided in patients with normal cardiovascular systems by maintaining adequate hydration and fluids intravenously. In patients with compromised cardiovascular systems, however, this combination technique may be contraindicated. In these cases, a spinal procedure can be performed, but the narcotics instilled only for postoperative pain management, skipping the anesthetic agent that might cause problems when combined with the general.