- Anesthesia Overview
- Preoperative Medical Exam
- Anesthesia Risks and Side Effects
- Spinal Headache
Anesthesia is the control of pain during medical procedures by the utilization of medications to block pain or the perception of pain. It can range from total lack of awareness called general anesthesia to lack of awareness of a part of the body through regional or local anesthesia.
An anesthesiologist is a physician who has received specialized training in the use of anesthesia drugs and techniques. An anesthesiologist may be assisted by a CRNA (certified nurse anesthetist). A CRNA is a registered nurse who has attended a two year nurse anesthesia training program. Our CRNAs always work under the supervision of an anesthesiologist.
Any type of anesthesia includes some risk; however, advances in anesthesia have made it quite safe while minimizing side effects and making patients comfortable. These advances have opened surgical options for many patients who otherwise would not be candidates for surgery. There are some health conditions that will increase your chance of problems from anesthesia, but working closely with your physician will decrease your risk.
There are four types of anesthesia:
General Anesthesia - Medication administered through an IV causing loss of consciousness. Often times the insertion of a breathing tube is necessary to maintain normal breathing during the procedure.
Regional Anesthesia – A section of the body is temporarily made numb by an injection of local anesthesia (numbing medicine) around nerves. This may be combined with sedation or general anesthesia, depending on the procedure. Often this can also be used for postoperative pain control.
Sedative Anesthesia – IV medication is administered to help with deep relaxation while still able to respond to commands and physical stimulation.
Local Anesthesia – Numbs on a small area of skin or tissue by injection.
*General Anesthesia – General anesthesia means you will be completely unconscious during surgery. Under general anesthesia the patient feels nothing and remembers nothing about the procedure. This anesthesia is given through an IV or mask, or both. Sometimes children are afraid of the injections so they are given anesthesia in the mask and then the IV is inserted after they are asleep.
*Surgery with General Anesthesia - Upon entering the operating room, the anesthesiologist will set up heart, blood pressure and breathing monitors. The anesthesia is administered through the IV. Since general anesthesia can impair normal breathing sometimes assistance is needed. Once the patient is asleep a breathing tube may be inserted. During the procedure the anesthesia team is there to monitor the vital signs and administer medication as needed. The breathing tube is usually removed as the patient is awakening. Most patients will not remember this breathing tube; however, a mild sore throat that lasts one to days can occur.
You may be asked by your surgeon to be evaluated by your family practitioner or internist prior to surgery. This evaluation will determine if you are in optimal physical condition to undergo anesthesia and surgery. It will also provide important information which will help your anesthesiologist to determine the best type of anesthetic to offer you and to assess the need for any special monitoring techniques during surgery.
If you have heart disease, please ask your doctor to forward the results of any recent studies (stress tests, cardiac catheterization, echocardiogram, etc) in addition to their pre-op evaluation for review by the anesthesiologist. Occasionally, a visit to the cardiologist may be necessary. Other specialist consultations or tests may be requested to ensure that you are in the best possible condition for surgery.
Appropriate blood tests will be determined individually for each patient. Women of child bearing age will need a pregnancy test before elective surgery.
Try to reduce caffeine intake before surgery to avoid withdrawal headaches. Cutting down on cigarette use will help reduce your risk of pulmonary complications. Ideally, one should quit smoking 6 weeks before surgery but even 48 hours of smoking cessation has been proven to be beneficial.
Patients undergoing procedures with any type of anesthesia should arrive in the OR with an empty stomach. Anesthetic medications may depress the cough reflex and allow any regurgitated material to enter the lungs where it may cause a severe reaction known as "aspiration pneumonia."
For adults, no food or non-clear liquids (juice with pulp, milk, coffee with cream, etc.) should be consumed for at least 8 hours prior to surgery because these take longer to pass out of the stomach and can cause greater damage if they should enter the lungs. Clear liquids, such as water, black coffee, plain tea, or apple juice can be taken up to 2 hours before surgery. Any intake of non-clear liquid or food within 8 hours of surgery may cause your surgery to be delayed or rescheduled.
Please call your anesthesiologist for guidelines concerning infants and children.
Most medications can be taken the morning of surgery with a sip of water. The following is a broad guideline for some common medications. If you have a specific question, please call you doctor or call the hospital and ask for the Department of Anesthesia or the anesthesiologist on call.
Blood pressure medication - should be taken as usual the morning of surgery except for diuretics. (fluid pills) Diuretic medication should be skipped the morning of surgery. These include Lasix (furosemide), Hydrochlorthiazide (HCTZ), Lozol (Indapamide) and others.
Insulin – consult your physician
Oral diabetes medication – do NOT take on the morning of surgery.
Metformin, a diabetic medicine, must be stopped 24 hours before surgery. Please take note that metformin is in Metformin, Fortamet, Glucophage, Glucophage XR, Glumetza,Riomet, glipizide/metformin, glyburide/metformin, pioglitazone/metformin, repaglinide/metformin, rosiglitazone/metformin, saxagliptin/metformin, and sitagliptin/metformin.
Thyroid medication – can be taken
Heartburn or ulcer medication – acid blockers (Zantac, Prevacid, Pepcid, Axid, Prilosec) should be taken on the morning of surgery to reduce the risk of aspiration pneumonia. However, antacids like Maalox, Tums or Carafate should NOT be taken because they contain particulate material that may cause damage to the lungs if aspirated.
Aspirin – consult your doctor
Asthma inhalers – should be used the morning of surgery and brought to the hospital with you.
Whenever a person undergoes anesthesia, there are risks involved. These risks could range from relatively minor complications to life-threatening situations. With this in mind, an anesthesiologist along with a highly trained anesthesia care team will be assigned to each patient.
Some side effects include a sore or scratchy throat after general anesthesia, muscle aches, backache or soreness or bruising at needle insertion sites and infrequently a puffy or sore lip and tongue following surgery. The type of surgery, anesthetic medication, changes in blood pressure or other physiologic status as well as patients who are prone to motion sickness all interact and may contribute to nausea. There are a host of anti-nausea drugs that have reduced the occurrence of post-operative nausea. If you have experience post-operative nausea in the past, please make your anesthesia care team aware so they can give you preventive medications.
Serious or life-threatening complications following anesthetics seldom occur. Complications such as stroke, heart attack, severe lung problems or severe metabolic disturbances are rare.
The hallmark of a spinal headache is a headache that becomes very intense when you stand up and goes away or gets much better when you lie down. It may occur after a spinal or an epidural anesthetic or after a diagnostic lumbar puncture (spinal tap).
The cause of a spinal headache is the leakage of spinal fluid through a puncture site in the dura (the sac surrounding the spinal cord and spinal nerves. The brain and spinal cord "float" in a fluid filled sac and when that fluid is lost, the brain will "sag" due to gravity when in an upright posture. The traction created on surrounding structures caused the headache.
During a spinal anesthetic, the dura is purposely punctured to inject medicine into the spinal fluid. Significant leakage leading to a headache is rare because the needle used is very small and the tiny puncture site heals quickly and does not allow much leakage.
During an epidural anesthetic, the dura is usually not punctured, so a spinal headache is generally not possible. However, since the dura is very close to the epidural space it can accidentally be punctured during epidural placement (~1%). Since the epidural needle is larger then the spinal needle (to allow placement of the epidural catheter) significant leakage leading to a headache is more likely. The overall risk of a spinal headache after spinal or epidural anesthetic is about one in a hundred or less. The risks are small in the very young, highest in young adults, and declines as we age. Conservative measures include bed rest, increased fluid intake, caffeine and an abdominal binder. Spinal headaches will almost all resolve over time.
For severe spinal headache, a blood patch can be performed. A blood patch is a highly effective treatment for a spinal headache. About 90% of spinal headaches will be relieved within 5 to 30 minutes and will require no further treatment. The remaining 10% will require a second patch.
The patient is usually given a dose of IV antibiotics prior to the procedure. The patient is placed in the sitting position and the back is sterilely prepared with iodine or alcohol solutions. A needle or catheter is placed in the epidural space exactly as it would be for an epidural anesthetic Then a small amount of blood is sterilely withdrawn from the patients arm and injected into the epidural space. This blood will clot and "patch" the hole in the dural sac, preventing any further leaking of spinal fluid. It also slightly compresses the sac, "buoying" up the brain, thereby quickly relieving the headache. Since the patients own blood is used, there is no risk of introducing blood borne infections, such as AIDS and hepatitis. The patient can resume normal activities.