What are the risks of surgery in Parkinson patients?

Written by Dr. A. Lieberman
http://www.parkinsonresearchfoundati...572&Itemid=107

What are the risks of surgery, any surgery, including brain surgery, in Parkinson patients?

What are the risks of anesthesia in Parkinson patients?

This is an update of a previous paper by Dr. Lieberman - Updated February 25 2007

Everyday, people with PD, like people without PD, face surgery. This includes relatively minor surgery such as tooth extraction, biopsy of a mole, biopsy of a breast, biopsy of a prostrate, colonoscopy, cataract surgery. This includes major surgery such as coronary artery by-pass, removal of a cancerous lung, or kidney, or pancreas, repair of a ruptured aneurysm, or surgery on the back or neck for a herniated disc and/or spinal stenosis. In addition, people with PD are more likely, than people without PD to undergo surgery for a broken hip or shoulder (as a result of a fall) or deep brain stimulation (DBS).

Surgery, although painless because of anesthesia, places major physical and psychological stresses on a person. These include the stress of Anesthesia, Surgery, and the stress of Parkinson Disease. The stress consists of the
psychological stress of anticipation, of fear, of uncertainty, with a person worrying:

1. If the tumor, if it is cancer surgery, is benign or malignant? If the surgeon can remove all of the tumor or only part of it? If a second or a third operation will be needed? If the surgery will go well or if there will be complications? If the surgeon can remove all of the tumor or only part of it? If a second or a third operation will be needed? If the surgery will go well or if there will be complications?
2. There is the stress of the post-operative period, the stress after the surgery with a person worrying: If there will be pain and if the pain can be controlled? If he or she will have to be on a respirator, or will need a feeding tube, or kidney dialysis? If he or she will need a blood transfusion and if a blood transfusion or transfusions are needed will there be complications such as AIDS. If he or she will be scarred or disfigured? If he or she will be in a coma?

Modern day anesthesia and surgery are relatively safe and patients who in the recent past were too sick or too old to have surgery because of failing hearts, or lungs, or kidneys, or advanced age are able to undergo surgery. But because they have failing hearts, or lungs, or kidneys, or are advanced in age, they are more vulnerable to complications. In addition the types of surgery being done today: deep brain stimulation, removal of formerly inoperable tumors, organ transplants, replacement of entire hips and knees, are more complicated, require sophisticated anesthesia and monitoring, and are more likely to result in complications with the best and most experienced surgeons and anesthesiologists and in the most advanced hospitals

Patients and families are aware of the sophistication and specialization of surgeons: neurosurgeons who operate only on aneurysms or brain tumors or who do only DBS. Cardiac surgeons, lung surgeons, belly surgeons, cancer surgeons. Orthopedic surgeons who only replace hips or knees. Patients and families are less aware of the sophistication and specialization of anesthesiologists and their fields: cardiac anesthesia, neurosurgical anesthesia, obstetrical anesthesia, orthopedic anesthesia, and pediatric anesthesia.

Anticipation, fear, uncertainty, worry are psychological stresses and through the ANS, abbreviated ANS can be changed into physical stresses.

The ANS can constrict (narrow) blood vessels and decrease the blood supply to the heart, the brain, the kidney, the skin. The constriction of blood vessels to the heart and brain can make a person more vulnerable to a heart attack or stroke. Constriction of blood vessels to the skin results in a cold, clammy, unpleasant feeling. Can raise blood pressure increasing the risk of heart attack or stroke. Some PD patients, about 25%, have orthostatic or postural hypotension (a drop in blood pressure on sitting or standing-up) related to an insufficiency of the ANS). And some of these patients have supine hypertension (a marked increase in blood pressure upon lying down). These patients may be more prone to rises and falls of blood pressure during surgery.

The ANS can increase the heart rate, increasing the risk of abnormal heart rhythms. Some PD patients are on a class of drugs called anti-cholinergic drugs including Artane, Cogentin, and Kemadrin. Some are on anti-depressant or sleep promoting or muscle relaxant drugs that have anti-cholinergic properties such as the class of drugs called Tri-cyclic anti-depressants, drugs such as Elavil. All drugs with anti-cholinergic properties (so called because the block the action of a naturally occurring chemical called acetylcholine) can increase the heart rate.

The ANS can constrict, narrow, the airways and/ or can increase the respiratory rate, thus increasing the risk of asthmatic attacks or post-operative lung complications such as edema (fluid) or pneumonia. A PD patient who has shortness of breath because of PD may be more vulnerable to these complications.

The ANS can increase the tremor or dyskinesia of a person with PD. Although the tremor or dyskinesia will disappear during anesthesia it can re-appear, and if marked, can complicate the healing process. Thus a hip that has been replaced may not be as stabile in a PD patients whose legs are trembling or moving involuntarily because of anesthesia.

The ANS can increase the anxiety and depression already present in people with PD, can increase the risk of some of the complications noted above.

The ANS can, in some PD patients, contribute to periods of post-operative agitation, confusion, delusions, disorientation, and hallucinations called Intensive Care Unit (abbreviated ICU) psychosis sun-downing. PD patients who suffer from dementia or who have had a history of agitation, confusion, delusions, disorientation and hallucinations on PD drugs are more vulnerable to these complications.

In addition to the psychological stress there are physical stresses including: Inserting, during general anesthesia, a breath tube through the throat and into the lungs and connecting it to a respirator. Inserting, if necessary, monitors into veins and arteries.

Administering a curare-like agent, a muscle relaxant, to paralyze the muscles, allowing more complicated surgery to be performed. Some PD patients, particularly patients with advanced PD may have more difficulty recovering from the effects of the muscle relaxant. Muscle relaxants, curare-like paralyzing agents, are NOT the same as muscle relaxants prescribed by for pain and inflammation. The muscle relaxants prescribed for pain and inflammation are NOT related to curare, do NOT cause paralysis, and share a name, not the physical properties of muscle relaxants administered during surgery.

Administering an anesthetic agent, either a narcotic, or a gas, to achieve a sufficient degree of anesthesia to allow the surgery to be performed. Certain PD drugs, selegiline and rasagaline (Azilect) block an enzyme in the body called MAO-B. There have been reports of adverse interactions between selegiline and certain narcotics, especially Demerol. As a rule it is recommended that all MAO- A inhibitors (drugs administered for certain types of depression) and MAO-B inhibitors be stopped at least two week before elective surgery. In emergency surgery the surgeon and anesthesiologist must deal with the potential problem as necessary.

Administering drugs, anti-hypertensives, drugs that lower blood pressure. If the blood pressure goes to high, administering drugs, called pressors, if the blood pressure drops too low. In PD patients with ANS insufficiency, with supine hypertension, extra care must be taken.

Administering fluids, balanced solutions of electrolytes (sodium, potassium, chloride, and bicarbonate), and/ or blood if the blood and fluid loss from the surgery requires it while monitoring the patient too make certain the patient is neither over-loaded with fluid (resulting in congestion and edema) neither dehydrated.

Cutting through skin, muscle, joints, joints, ligaments, and organs.
Drilling, when necessary, through bone.

Handling, manipulating, pulling, and tugging arteries, organs, nerves, and veins that were not meant to be handled or manipulated or pulled or tugged.
Re-arranging the body’s architecture such as creating connections between arteries, organs, ducts, and tubes that never existed removing and replacing organs or parts of organs.

Thyroid hormone, steroid hormones, epinephrine (adrenalin) and norepinephrine (noradrenalin) from the adrenal gland speed up bodily processes, increasing metabolism, resulting in a greater need for oxygen, for blood flow, for processing and removal of waste products such as carbon dioxide, nitrous oxide, and urea: products that if not removed cause problems.

For the PD patient the psychological and physical stress may require additional PD drugs, drugs that the patient cannot receive because his stomach and bowels may, temporarily, not be functioning after the surgery.

Several factors can affect the activity of anesthetics including the sex, the age, the patient’s height and weight ( body size), the presence of heart, lung, liver, or kidney disease, the use of concurrent drugs. Several studies demonstrate that managing pain before it begins, is of significant benefit. Analgesia is more effective when given before a painful procedure. The duration of anesthesia produced by the anesthetic should coincide with the expected duration of the surgery.

The duration of analgesia produced by the analgesic should coincide with the expected duration and intensity of the post-operative pain caused by the surgery. If surgery was done under general anesthesia, and the surgery is over, the paralysis from the muscle relaxant may persist. There is debate as to whether such paralysis is more likely to persist (for a few additional hours) in people with PD. As a rule, with exceptions, in patients with amyotrophic lateral sclerosis (Lou Gehrig disease) and in other disorders where there is atrophy and wasting of muscles, the paralysis from the relaxant may persist (for a few additional hours or days).

During this time the patient remains on a respirator or ventilator and is watched closely in an ICU (an Intensive Care Unit). Succinyl choline, a particular muscle relaxant, may in patients with Lou Gehrig disease and other disorders with marked atrophy and wasting of muscles result in high blood levels of potassium (called hyperkalemia).

As a rule, with exceptions, this should not be a problem in PD: unless there is marked atrophy and wasting of muscles. High blood levels of potassium if NOT treated promptly can lead to erratic heart beats and death.

A special problem for PD patients who undergo major surgery under general anesthesia, especially bowel surgery, is their inability to take anti-PD drugs by mouth. Parcopa, carbidopa/ levodopa, which dissolves in the mouth, may or may not be absorbed in a bowel that, in essence, is not working. The rotigotine (Neupro) patch may be used if the patient cannot take medication by mouth.

As a rule, with exceptions, PD patients who have had PD for 5 years and under, can usually tolerate several days without anti-PD drugs. As a rule, with exceptions, PD patients who have had PD for 10 years or longer cannot, usually, tolerate 3 or more days without anti-PD drugs.

As a rule, with exceptions, PD patients who had PD for between 5 and 10 years, fall between the two extremes. As a rule, with exceptions, in most PD patients, including patients who have had major bowel surgery, anti-PD drugs by mouth can be restarted within 48 hours. In those patients who cannot be re-started on anti-PD drugs by mouth, Apokyn, an anti-PD drugs can be given by injection or the rotigotine patch may be used.

As a rule, with exceptions, the consequences of NOT taking PD drugs in people with advanced PD is increased rigidity, decreased movement, decreased ability of the lungs to properly ventilate the body, increased secretions with inability to clear the secretions with the risk of pneumonia.
In addition, there is the risk of a neuroleptic malignant syndrome (abbreviated NMS).

The main risk to people with PD who undergo major or minor surgery under general, regional, or local anesthesia is similar to people without PD of a similar age. As a rule, with exceptions, the risk is the risk of the co-morbid conditions: the presence of heart, lung, or kidney disease independent of PD. As a rule, with exceptions, people with PD, especially advanced PD, may have more problems with swallowing and respirations. A report (see abstract below) suggests that heart failure is more common in people with advanced PD than in comparably aged people without PD.

The hearts of people with or without PD who undergo general anesthesia are subject to multiple stresses and complications. Thus a person whose heart was previously compensated, may decompensate after surgery leading to increased morbidity and mortality. Each year, approximately 30 million people in the United States undergo non cardiac surgery.

Approximately one third of PD patients have heart disease or major heart risk factors. Estimated rates of serious heart complications vary from 1-10%. The incidence of heart complications during and after surgery are increased 10- to 50-fold in people who have had previous heart complications. The effects of general anesthesia on the heart include changes in arterial pressure, in venous pressures, in cardiac output, in heart rhythms, in vascular resistance, and in heart muscle contractility.

In addition, gas anesthetics, intravenous narcotic anesthesia, and muscle relaxants can sensitize he heart muscle by increasing circulating catecholamines (epinephrine and norepinephrine)and this combined with increasing catecholamines from the stress of surgery can increase the risk of ventricular arrhythmias (potentially fatal heart rhythms).

People, especially PD people who have orthostatic or postural hypotension and/ or supine hypertension related to an impaired autonomic nervous system must be certain to speak to the anesthesiologist before the surgery and apprise the anesthesiologist of the PD person’s problem with blood pressure. As a rule, inserting a tube into the trachea before anesthesia raises blood pressure by 20 to 30 mm of mercury, while general anesthesia lowers arterial pressures by 20-30%.

Approximately 40% of people who are aware they have high blood pressure are either not treated or inadequately treated. Poorly controlled high blood pressure is associated with an increased incidence of heart attack, arrhythmia, and stroke. People with high blood pressure are at a higher risk for labile blood pressure (swing between high and low pressure) and for hypertensive emergencies during surgery and immediately following surgery. People, including people with PD, should continue taking their anti-hypertensive drugs throughout the period before the surgery.

The PD drugs selegiline and rasagiline (Azilect), drugs that block the enzyme MAO-B, may, in some people interfere with the metabolism of narcotics. This MAY include the narcotic anesthetics such as fentanyl, sufentanil or alfentanil. Selegiline and rasagiline have been reported to interfere with the metabolism of meperedine (Demerol) used not for anesthesia, but for treating post-operative pain. The interaction of selegiline and rasagiline and meperedine may in an increase in PD symptoms. Although selegiline and rasagiline have has been continued in some patients undergoing emergency surgery using narcotic anesthesia (abstract below) it is recommended that selegiline be stopped at least 2 weeks before elective surgery. In cases of emergency surgery, the anesthesiologist must be made aware of the fact that the PD patient is using selegiline. What is true for selegiline is doubly true for people with or without PD who are taking a class of anti-depressant drugs that blocks, inhibits the enzyme MAO A.

Local anesthesia (anesthetizing a small region), regional anesthesia, spinal and epidural anesthesia do not require muscle relaxants, do not require intubation (insertion of tube into the trachea) and , in general, are less physically stressful although, in many patients, they are more psychological stressful than general anesthesia: It is easier, psychologically, to think of sleeping through an operation than to imagine being awake during the operation. However, local, regional, spinal and epidural anesthesia have their own potential problems.

Thus epidural and spinal anesthetics cause dilatation of arteries and veins by blocking the outflow of the sympathetic part of the ANS, thus decreasing cardiac output. To offset this effect, the surgeon may volume load (administer fluids intravenously) to the patient before surgery. However, this can increase the risk of congestive heart failure after the surgery. In a person with PD who has marked tremor or marked dyskinesia, these may increase during surgery with local or regional anesthesia. This possibility should be discussed with the anesthesiologist and the surgeon to determine whether this may or may not be a problem.

Drugs such as anti-cholinergics, tranquilizers, or sedatives are given as anesthetic pretreatment for a variety of reasons. The primary goal of pretreatment with the majority of these drugs is to minimize anxiety or excitement of the patient. Some drugs may be used to ease the transition to the first plane(s) of anesthesia, to decrease the amount of anesthetic agent, to prevent vomiting, or to control secretions.

Deciding the type of anesthesia is made by the anesthesiologist, the surgeon and the patient. The decision is made after taking a medical history and doing a thorough examination. Factors contributing to the choice of anesthesia include the patient's attitude and affect. Some patients want to be "asleep" for the duration of the surgery, fearing any pain or the chance of hearing what is being said during surgery.

Some patients are afraid of general anesthesia and of having a tube stuck down their throat. If the patient does not want general anesthesia and insists upon intravenous sedation it is possible that the level of anesthesia may not be adequate for the procedure, especially if the procedure is long and complications develop.

The mortality rate following non cardiac surgery increases with worsening cardiac class (see American Society Anesthesiology classification below), and/ or the presence of lung congestion. The perioperative- mortality rate is as a rule, with exceptions, more dependent on the person’s condition at the time of surgery than on the myocardial depressant effects of the anesthesia.
People with or without PD who are on anti-coagulants, coumadin, must report this to the anesthesiologist and surgeon. As a rule coumadin should be discontinued 4-5 days before elective surgery. People at high risk for embolic events including people with phlebitis, with atrial fibrillation, with aortic stenosis, with artificial heart valves are usually admitted to the hospital before surgery and started on intravenous heparin.

The above is general information so you, the patient, can have an intelligent discussion with the anesthesiologist and surgeon. The decision on the type of anesthesia: local, regional, spinal, general with narcotics, muscle relaxants, and/ or inhaled gases will be based on the type of procedure, the duration of the procedure, the probability of post-operative complications.

Factors that will be considered include the severity of the underlying PD. As a rule, with exceptions, the severity is determined by the severity of the underlying PD, the presence or absence of dementia, and the presence or absence of co-morbid conditions such as high blood pressure, fluctuating blood pressure, heart disease, lung disease, liver disease and kidney disease. In addition the PD and non PD drugs may be factors. As a rule, with NO exceptions, ask to speak to the anesthesiologist who will be giving the anesthesia and make certain he or she understand PD and the drugs you are taking for PD.

Definitions

Analgesia: relief from pain

Anesthesia, Local: loss of sensation in a limited body area. A variety of local anesthetic drugs are available including lidocaine and bupivicaine are used for dental procedures, for biopsies. Loss of sensation in a limited body area. A variety of local anesthetic drugs are available including lidocaine and bupivicaine. Used for dental procedures, for biopsies.

Local and regional anesthesia with sedation offers flexibility in tailoring the degree of anesthesia to the needs of the patient. Procedures that once required patients to stay overnight in the hospital now are performed safely in office and outpatient surgical suites. The introduction of new anesthetic applications enables patients to undergo complex procedures as outpatients and then promptly and safely be discharged home. The choice and route of anesthesia administration is critical. If the patient upon discharge is alert, has minimal pain, and has no nausea or vomiting, then their surgical experience is a positive one.

Anesthesia Basal: a light level of general anesthesia usually produced by pre-anesthetic drugs. It serves as a basis for deeper anesthesia on administration of other drugs

Anesthesia, Epidural: anesthetic drug delivered into the space between the dura (the outer covering of the spinal cord) and arachnoid (the inner covering of the spinal cord). The anesthetic does NOT enter the spinal fluid, and the anesthetic area is localized. Used for delivering babies.

Anesthesia, General: complete unconsciousness

Anesthesia, Regional: insensibility in a larger, though limited, body area.

Anesthesia, Spinal: anesthetic drugs delivered into the spinal fluid through a spinal tap resulting in anesthesia usually up to be mid spine (at the level of the umbilicus). May be used for hip and knee replacements.

Anesthesia, Surgical: unconsciousness, accompanied by muscular relaxation to such a degree that surgery can be performed painlessly and without struggle on the part of the patient.

Anesthesia, Volatile: Includes gases such as halothane, enflurane, isoflurane, sevoflurane, and desflurane. These gases should be administered by a trained anesthesiologists in an operating room with adequate ventilation or scavenging systems. Precision vaporizers must be used for these gases because lethal concentrations can easily be reached using an open drop method.

Anti-cholinergic Drugs: Agents such as atropine and glycopyrrolate block parasympathetic nerve impulses to the heart, the lungs, the endocrine glands and the smooth muscle of the stomach, intestines, and balder. They prevent vaso-vagal reflexes, those reflexes , that can result in marked slowing of the heart. The anti-cholinergic drugs decrease salivary gland and bronchial secretions

Ketamine: a non-barbiturate, rapid-acting anesthetic used on both animals and humans. It is relatively easy to administer, can be given intravenously or intra muscularly. It is a sympathetic nervous system stimulant and may result in an increased heart rate and respiratory rate. It is often used in pediatric anesthesia, in dentistry, and psychotherapy (similar to but safer than barbiturates). Ketamine has a greater analgesic effect than propofol a similar drug. Ketamine is similar in structure to PCP or Angel Dust. Unfortunately it is being abused by some people as a "club drug," and is often distributed at "raves" and parties.

Adverse effects can range from rapture to paranoia to aggressive maniacal behavior. The effects of ketamine usually last an hour but can last for 4-6 hours. Large does can cause vomiting and convulsion. Patients on anti depressant drugs called MAO A inhibitors and PD patients on selegiline, an MAO B inhibitor should not be given ketamine. Because of the possibility of interaction between anti depressant drugs called SSRIs and ketamine, the surgeon and anesthesiologist MUST be informed of their use.

Malignant Hyperthermia (MH) is a relatively uncommon disorder, that is usually inherited, and usually has appeared at in the past (assuming the person had surgery in the past). MH first manifests itself, to the anesthesiologist, as an increase in end-tidal CO2. MH is characterized by the sudden onset of muscle rigidity, tachypnea (rapid breathing), tachycardia (rapid heart rate) and hyperthermia (rectal temperatures of up to 108oF), followed by dyspnea (difficulty breathing), cardiac arrhythmias, apnea and even death. Anesthesia particularly with inhaled gases such as halothane or isoflurane coupled with marked excitement have all been reported to trigger MH.

In many ways, MH resembles neuroleptic malignant syndrome (NMS) Emergency measures include stopping the anesthetic, cooling the body with ice water, and the intravenous administration of sodium bicarbonate and the muscle relaxant dantrolene

Narcosis: a drug-induced state of sedation in which the patient is oblivious to pain

Neuromuscular Blocking Drugs (muscle relaxants): Muscle relaxants, curare-like drugs, such as Succinyl-choline, can block the transmission of nerve impulses at the junction between nerves and muscles. Other muscle relaxants can block the transmission of nerve impulses in the spinal cord and in ganglia located between the spinal cord and the peripheral nerves. These drugs produce a profound paralysis of skeletal muscle without loss of consciousness. They are used as adjuncts in anesthesia to obtain more complete muscle relaxation without a deeper plane of anesthesia. Some of the drugs are depolarizing: their effects cannot be reversed (until the drug wears off) and some are non depolarizing: their effects can be reversed.

Nitrous oxide: a commonly used general anesthetic, can lower cardiac output by 15%. Narcotic anesthetics such as fentanyl, sufentanil, or alfentanil as a rule, with exceptions, result in less myocardial depression compared to inhaled anesthetics such as nitrous oxide. However, the narcotic anesthetics can dilate veins, reduce flow to the heart, and lower cardiac output. Patients who suffer from heart failure may be particularly sensitive to these changes.

Propofol or Diprivan: An intravenous sedative-hypnotic agent for use in the induction and maintenance of anesthesia or sedation. Intravenous doses of propofol produce hypnosis rapidly with minimal excitation, usually within 40 seconds from the start of an injection (the time for one arm-brain circulation). As with other rapidly acting intravenous anesthetic agents, the half-time of the blood-brain equilibration is approximately 1 to 3 minutes, and this accounts for the rapid induction of anesthesia. Pharmacodynamic properties of propofol are dependent upon the blood propofol concentrations. Steady state propofol blood concentrations are generally proportional to infusion rates, especially within an individual patient. Undesirable side effects such as cardiac or respiratory depression can occur at high levels.

Sedation: a mild degree of drowsiness in which the patient is awake but calm; larger doses of sedative drugs may lead to narcosis. Sedatives include barbiturates and benzodiazepines such as Ativan, Medazolam, and Valium.

Tranquilization: A state of behavioral change in which the patient is relaxed, unconcerned by its surroundings, and often, indifferent to minor pain. Tranquillizers include drugs called phenothiazines such as Thorazine. They include butyrophenones such as droperidol and haloperidol (Haldol). Phenothiazines and butyrophenones can, temporarily aggravate PD.

The distinction between tranquilizers and sedatives is one of language. One difference, however, is that tranquilizers at high doses can cause side effects without a loss of consciousness. Sedatives at high dose levels can cause a loss of consciousness, coma, that resembles anesthesia. Tranquilizers are calming and can reduce the amount of anesthetic drugs required for induction and maintenance of general anesthesia, thereby decreasing the undesirable side-effects of the anesthetic drugs. Tranquilizers also may enhance smooth anesthetic recoveries (usually in conjunction with analgesics).

Risk Classification of Surgical Procedures

High-risk: greater than 5% rate of peri operative death or heart attack. Includes heart valve surgery, peripheral vascular surgery, abdominal and thoracic aneurysms, any prolonged procedures with large amounts of blood loss involving the abdomen, thorax, head, and neck

Intermediate-risk: 1-5% rate of peri operative death or heart attack. Includes urologic, orthopedic, and uncomplicated abdominal, head, neck, and chest operations


Low-risk: less than 1% rate of peri operative death or heart attack. Includes cataract removal, endoscopy, breast surgery, biopsies.

Risk factors for death and heat attack include: a history of a previous heart attack, a history of arrhythmia, a history of congestive heart failure, a history of aortic stenosis. A patient who is 70 years or older, a patient who is in poor medical status, emergency surgery.

Risk Classification, American Society of Anesthesiologists
(an aid in estimating general health and clinical status of patients).

Class 1 - Healthy patient.
Class 2 - Mild-to-moderate systemic disease
Class 3 - Severe systemic disease that limits activity
Class 4 - Incapacitating and life-threatening systemic disease
Class 5 - Moribund with little chance of survival with or without surgery.
Class E - Patient undergoing emergency surgery

Stages of General Anesthesia
Stage I: Loss of pain without loss of consciousness or sense of touch. This stage exists from the moment of induction to the loss of consciousness. Respiration is unchanged, and the pupils may not change or exhibit moderate reflex dilation. Analgesia is present.

Stage II: Loss of consciousness to the onset of regular respiration. In this stage, the higher cerebral centers are depressed with loss or inhibition of the secondary centers. Excitement and struggling may occur.

Stage III: Loss of spontaneous respiration due to central respiratory paralysis from the action of the anesthetic agent.

Plane 1: Respiration is regular with an increase in tidal volume. There is a loss of the vomiting, eyelid, and pharyngeal reflexes.
Plane 2: Respiration is regular but shallower. The eyeballs are fixed (central) and the pupil is in mid-dilation. There is a loss of the corneal, visceral, laryngeal, and cough reflexes. The large muscles are beginning to relax,
Plane 3: Progressive inter-costal muscle lag, in which diaphragmatic movement precedes the action of the intercostals. It ends with the cessation of inter-costal movement. The pupil is moderately dilated and all muscle tone (except diaphragmatic) is lost.
Plane 4: Complete inter-costal paralysis and breathing is diaphragmatic.

Evaluation of anesthetic effects:
Reflexes are absent and muscle tone is relaxed during surgical anesthesia. The anesthesiologist monitors the depth and rate of respiration - increase in depth and decrease in rate signifies surgical anesthesia. The anesthesiologist monitors the heart rate. An increase in rate during surgery may indicate more anesthesia is required, a decrease in rate may indicate less anesthesia is required. The anesthesiologist monitors body temperature. Too high or too low a temperature may have detrimental consequences.

Severity of Parkinson Disease
The severity of a person’s PD, a possible risk factor for surgery, can as a rule, with exceptions, be gauged by the duration of the person’s PD (as measured from the date the person was diagnosed):

Mild PD: duration of PD: 0 to 5 years

Moderate PD: duration of PD: 6 to 10 years

Advanced PD: duration 11 plus years.

The severity of the PD is less in the absence of autonomic nervous system insufficiency and dementia. The severity of the PD is more in the presence of autonomic nervous system insufficiency and dementia.

The Stage of PD, another measure of the severity of PD, is assessed using the Hoehn and Yahr Stage

In 1967, before L-dopa or levodopa, Drs Margaret Hoehn and Melvin Yahr began rating people with PD on a 6-point scale: 0, 1, 2, 3, 4, 5. In 1967, the Scale reflected the underlying state of their PD. L-dopa changed PD, symptoms receded and became masked or hidden. L-dopa, however, , doesn’t halt the progression of PD.

Thus, when a person with PD is rated, the rating reflects not the underlying PD, but your outward appearance. To rate the underlying PD state, L-dopa (in the form of carbidopa/ levodopa or Sinemet) must be stopped for at least one month. For most people with PD this is NOT impossible.

After 2 to 5 years many PD people fluctuate: the day consists of being "ON" (Sinemet working) followed by being "OFF" (Sinemet not working). If this is so the person with PD should be rated in both your "ON" and "OFF" state.

The Hoehn and Yahr Scale rates mobility. It does not rate anxiety, aberrant behavior, depression, dyskinesia, memory loss, difficulty thinking, or difficulty swallowing. In many people with PD these symptoms overshadow mobility. The Hoehn and Yahr Scale is NOT a Cancer Rating Scale: it is not a guide to treatment and outlook. However, despite its limits, the Scale has endured, attesting to its usefulness.


References
Hoehn MM, Yahr MD. Parkinsonism: onset, progression and mortality. Neurology (1967): 17: 427 - 442

The Movement Disorder Society Task Force on Rating Scales for Parkinson Disease. Movement Disorder Society Task Force Report on the Hoehn and Yahr Staging Scale: Status and Recommendations. Movement Disorders (2004): 10: 1020 - 1028

The Hoehn and Yahr Scale

Need for Antibiotics Before Surgery

According to the guidelines of the American Heart Association published in 1997, conditions in which antibiotics are recommended BEFORE a surgical procedure include the following circumstances and conditions.

Cyanotic congenital heart defect.

Deep brain stimulation, presence of a stimulator.

Hypertrophic cardiomyopathy.

Mitral valve prolapse, heart valve thickening.

Past history of infective endocarditis.

Presence of a cardiac pacemaker.

Presence of a prosthetic heart valve.

Surgically constructed systemic or pulmonary conduits, graft for an aneurysm

Very helpful post Carolyn. Potential surgical patients should review. I would consider highlighting specific areas that pertain your condition, and present a copy to their anesthesiologist and surgeon prior to the procedure. As a retired surgeon, I would have appreciated any information that would minimize potential complications.

For example, I take Rasagaline. 90% of my physician friends have never heard of the drug, let alone know it's potential side effects. This could cause significant drug interactions with certain anesthesics. I am shocked about how little they know about PD in general. It is naive to think that physicians know everything. If they did, there would much less work for lawyers (LOL).

Amen......and........Amen....!!!!!!!


Caya