The management of medical and surgical problems in Parkinson's disease

 Introduction

Parkinson's disease (PD) affects people of all ages. Although 20% may be diagnosed under the age of 50, the usual age of onset is between the sixth and eighth decades. With the advent of levodopa therapy 30 years ago, people now live with this disease for 20 to 30 years. As a result, physicians are seeing an increasingly aging population with PD often with concurrent acute or chronic medical and surgical problems. These individuals often have well-controlled PD, and an aggressive approach is appropriate when treating these problems as the outcome can be rewarding. In spite of this, the literature covering their concurrent medical and surgical problems is limited.

Patients with PD do not die as a direct result of their PD but are more likely to succumb to complications associated with immobility or other conditions.

Gorell and colleagues[1] reviewed the death certificates issued in Michigan between 1970 (when levodopa became available) and 1990 and compared underlying causes of death in two populations, one of which had PD listed as a contributing cause of death. They found PD patients more likely to die of stroke, pneumonia, and influenza, less likely to die of cancer, chronic obstructive lung and liver disease, and no more likely to die from diabetes mellitus or heart disease than patients in the other group. They speculated that cerebrovascular disease was more common in patients with PD because these patients were likely under the care of a neurologist who would diagnose and report it, thus leading to a reporting bias.

Increased risk of death from pneumonia or influenza is understandable because patients with advanced PD are immobile, rigid, and debilitated. These patients have reduced lung function and are also at increased risk for fractures, most often of the hip.

A full review of the anesthesiological management of PD and sexual function in PD are beyond the scope of this article; please see the "Suggested reading" list at the end of this article for more information on these topics.

Medical problems

Medical problems in the management of PD fall into two main categories. The first category is how medical conditions and their treatment affect patients with PD. The second is how PD and the disability associated with it can affect concurrent medical problems.

 Hypertension

One of the most frequent problems encountered in PD patients already treated with antihypertensives and/or diuretics is the development of symptomatic hypotension when antiparkinson drugs are introduced. Dopaminergic drugs lower blood pressure. In this setting the antihypertensive can be reduced or stopped. The blood pressure of treated hypertensive patients should be measured regularly, both lying (5 minutes) and standing (3 minutes) as antiparkinson drugs are initiated. Besides the acute changes, blood pressure can fall as a result of the weight loss so often associated with advancing PD. Patients with weight loss should not only be referred to a nutritionist but also have their blood pressure monitored.

Hillen and colleagues[2] found that subclinical (decrease of systolic BP >15 mm Hg) hypotension was associated with unexplained dizziness in elderly parkinsonian patients.

 Heart disease

A cardiac consultation is recommended for patients with severe or recent heart disease before initiating antiparkinson therapy for several reasons. Daniel and Mauro,[3] in a review of extrapyramidal syndromes caused by calcium channel blockers, report that flunarizine and cinnarizine in particular should be used with caution because of their propensity for inducing or worsening extrapyramidal syndromes. Our centre has seen this effect in PD patients taking calcium channel blockers.

Lees[4] reported increased cardiac mortality in patients with PD taking levodopa and selegeline. There is also a report of selegeline-induced atrial fibrillation in a patient with PD.[5] Dopamine agonists may worsen or cause cardiac arrhythmias, exacerbate angina, and are contraindicated in patients who have had recent myocardial infarction.[6]

 Osteoarthritis and gout

Treatment for PD improves mobility, which can exacerbate osteoarthritis, causing painful joints. Paradoxically, improved mobility increases the risk for falls and fractures.[6] Painful osteoarthritis exacerbates PD symptoms. Levodopa therapy may occasionally precipitate gout, which responds well to treatment.[7]

 Genitourinary

PD patients most commonly experience urinary problems related to frequency and urgency. It is challenging to determine whether a patient has a surgical problem, such as prostate hypertrophy, or whether the symptoms are related to autonomic dysfunction for which surgery is not only unhelpful, but can also exacerbate the problem.[8] In a retrospective study of postoperative complications in PD patients undergoing surgery unassociated with their PD, Pepper and Goldstein[9] found that these patients were significantly more likely to develop urinary tract infections.

If urinary problems are severe, multiple system atrophy should be considered and a neurology consult is recommended.

Reproductive issues in women

Women with PD may have premenstrual symptoms. Quinn and Marsden[10] reported on 11 women with increased symptoms coinciding with their menstrual cycles. Adjustments can be made to the antiparkinson regimen for a few days before the start of menstruation. Increased immobility requires an increase in antiparkinson treatment, and increased dyskinesia requires a reduction in dosage.[10]

 Pregnancy in PD

It is safe for women with young-onset PD to become pregnant. Hagell and colleagues[11] reported on 34 pregnancies in 28 women with PD. They note that healthy pregnancies are unlikely to be reported, creating a bias toward abnormal outcomes. Of the 27 pregnant PD patients on treatment, one on amantadine miscarried. The Vancouver Hospital Movement Disorder Clinic has monitored three pregnancies in two patients taking antiparkinson agents. One dystonia patient remained on trihexyphenidyl to 60 mg a day through two pregnancies. Another took levodopa-carbidopa (Sinemet) throughout her second pregnancy. Both delivered full-term healthy babies; neither reported a worsening of their symptoms.

Information on breastfeeding is limited. Amantadine enters breast milk,[12] and dopamine agonists suppress lactation. Thulin and colleagues[13] have measured levodopa levels in the breast milk of a nursing mother with PD. They found a subtherapeutic amount of levodopa in the milk, but admit that the data are not unequivocal. The benefits of breastfeeding should be weighed against the effects of maternal fatigue and disrupted sleep on symptoms. The Vancouver Movement Disorder Clinic recommends that patients not breastfeed.

 Menopause

Perimenopausal women may have symptoms that exacerbate their PD. A positive association has been found between estrogen use and lower disease severity in women with early untreated PD.[14] Marder and colleagues[15] suggested that hormone replacement therapy might reduce the risk of dementia in women with PD. These were, however, unblinded, retrospective studies. Many perimenopausal women with PD are uninformed about the risks or merits of hormone replacement therapy. If women are encountering distressing symptoms associated with menopause, their PD symptoms will worsen, and hormone replacement therapy may be helpful.

Medications that can induce or exacerbate parkinsonism

Some of the drugs listed in the Table not only worsen existing PD symptoms, but have the potential for inducing parkinsonism, leading to misdiagnosis. A complete drug history is important before making a diagnosis of idiopathic PD. If the offending drug can be withdrawn, symptoms should resolve. Though most physicians recognize that the antipsychotics can induce a Parkinson-like condition, many are not aware that antiemetics such as metoclopramide (Maxeran) have similar effects. PD-induced nausea should be treated with domperidone when associated with dopaminergic drugs. Dimenhydrinate (Gravol) can be used for other causes of nausea.

Encephalopathies

Acute confusional states are a common occurrence in late-stage PD. Although these are covered elsewhere in this issue, several discrete medication-induced problems need emphasis here.

Amantadine, a glutamate antagonist, is excreted almost completely unmetabolised through the kidneys and is contraindicated in patients with renal impairment.[12,16] However, it can cause a rebound confusional state if stopped abruptly.[17]

Ditropan, frequently used for bladder problems, may induce or worsen confusion due to its anticholinergic properties.

Ciproflexcin, potentiates ropinerol (ReQuip) and can precipitate confusion.

Non steroidal anti-inflammatory drugs can cause confusion in the elderly[18] and the Compendium of Pharmaceuticals and Specialties lists worsening of parkinsonism as a rare side effect of indomethacin. The Vancouver Hospital Movement Disorder Clinic admitted a PD patient who became mute and confused with worsening of his PD when prescribed indomethacin. He recovered following the withdrawal of the drug.

Demerol, often given postoperatively for pain control, frequently induces an acute confusional state in parkinsonian patients with no history of confusion or psychosis. PD patients tolerate morphine better if a narcotic is needed.

Surgery and Parkinson's disease

Little has been written about surgical problems in PD patients. In the recent textbook, Principles of Surgery (Schwartz, 1998), only two references are made to PD: one describes ablative surgery for PD; the other lists PD as one of many causes of constipation and slowed GI motility.

Surgical problems in PD are divided into two main categories. First, there are complications of PD that are treated surgically. Second, there is the pre-, peri-, and postoperative management of PD patients for all types of surgery.

 Orthopedic problems in PD

Fractures occur with higher incidence in PD patients than in age-matched controls.[1] In this 10-year, population-based study, 27% of PD patients experienced a new hip fracture. The greatest increase in risk is seen with femoral neck fractures. There are also increased shoulder fractures and frozen shoulders, although PD patients can sometimes present as "frozen shoulder." The increased risk of fracture is probably due to falls secondary to PD immobility and postural instability, rather than osteoporosis.[19]

 Gastrointestinal problems

Gastrointestinal motility is reduced in PD, leading to constipation.[20] As well, antiparkinson drugs can be constipating. Constipation is one of the most common problems PD patients encounter, and needs to be addressed at the time of diagnosis. Patients can have two kinds of constipation: hard, dry stools that are painful to pass due to slowed motility, and delayed emptying of a full bowel due to incoordination of rectal muscles.[21] The first responds to increased fluids, fibre, and stool softeners; the second can be relieved with suppositories. Prolonged constipation leads to surgical complications if it is not relieved. The Vancouver Hospital Movement Disorder Clinic is aware of several deaths in PD patients resulting from bowel obstruction leading to perforation. Three conditions can occur in PD patients: paralytic ileus, acute bowel obstruction secondary to impaction, or rarely, volvulus and pseudo-obstruction (Ogilvie's syndrome).[22,23]

General surgical management of PD patients

PD patients represent a management challenge in the surgical setting, needing extra attention and care.

 Preoperative care

For major surgery, some neurologists recommend withholding drugs for 8 hours to 12 hours prior to surgery.[24] Others feel that drugs can be taken up to the time of surgery with the smallest amount of liquid possible.[25]

 Perioperative care

PD patients should have local anesthesia or nerve blocks whenever possible to avoid the gastrointestinal and respiratory complications of general anesthesia and to allow them to continue to take their medication. If major surgery is planned, a nasogastric tube should be passed preoperatively to allow prompt resumption of antiparkinson medications in the event that the patient is allowed nil by mouth. There are, to date, no antiparkinson drugs that can be given parenterally or by suppository.[26]

 Postoperative care

The importance of prompt resumption of antiparkinsonian medications given as previously ordered cannot be overemphasized. If the patient is allowed nil by mouth and has a nasogastric tube, standard Sinemet can be crushed in a small amount of water and put down the tube, which is then clamped for 20 minutes.[27] Failure to do this delays recovery and increases the risk of postoperative complications and the patient's anxiety. Postoperative complications in unmedicated PD patients include aspiration pneumonia, thrombophlebitis, falls, fractures, and paralytic ileus. Upper airway obstruction has been reported,[26] particularly in unmedicated patients.

 Conclusion

Medical and surgical problems in PD patients need to be managed with consideration of the effects of both on the patient's PD, as well as the effects PD can have on the medical and surgical problems. Communication between all physicians involved in the management of these problems is important. The pre- and postsurgical management of PD patients should be planned not only by the surgeon and anesthetist, but also the physician who is prescribing the PD therapy.

Table. Drugs that induce or worsen parkinsonism

 Suggested reading

Basson R. Sexuality and Parkinson's disease. Parkinsonism Rel Disord 1996;2:177-187.

Mason LJ, Cojocaru TT, Cole DJ. Surgical intervention and anesthetic management of the patient with Parkinson's disease. Int Anesthesiol Clin 1996;34:133-150.PubMed Abstract

Pfeiffer, RF. Gastrointestinal dysfunction in Parkinson's disease. Clin Neurosci 1998;5:136-146.PubMed Abstract

Christopher Bozek MD, FRCPC, and Susan M. Calne, RN

Dr Bozek is a clinical instructor of neurology in the Division of Neurology at the University of British Columbia and is in private practice in Burnaby. Ms Calne is the coordinator of the Neurodegenerative Disorders Centre at UBC.