When the PD Patient Needs Surgery
WHEN THE PD PATIENT NEEDS SURGERY
by Michael Rezak, MD, PHD
Special consideration must be given to those individuals with PD who require any type of surgical intervention. The stress that surgical procedures can impose affects PD management, and although most patients with PD will not encounter difficulties, knowledge of potential problems may help to preclude their development. If problems do arise, being forewarned will allow prompt recognition, treatment and resolution. In the paragraphs that follow, I will address the questions most frequently asked by patients who are about to undergo surgical procedures. These questions (and answers) will also address some of the potential complications seen in PD patients undergoing surgery. I will not address questions related to neurosurgical procedures used to treat PD (issues related to deep brain surgery (DBS) are discussed in the Summer 2003 issue of this newsletter).
Q: WHEN SHOULD PD MEDICATIONS BE DISCONTINUED PRIOR TO SURGERY AND HOW SOON CAN THEY BE RESTARTED AFTER SURGERY?
A: It is my practice to encourage my patients to continue taking all PD medications up to 3 hours before surgery. The exception to this is selegiline (Eldepryl®), which I discontinue 2-3 weeks before surgery in order to avoid any possible interaction with certain narcotic analgesics. PD medications are restarted as soon as the individual can swallow safely. Unfortunately, there are no dopaminergic PD medications that are available for administration via intravenous, intramuscular or by rectal routes. If the patient is recovering from gastrointestinal surgery, I recommend giving the medications through a nasogastric tube which should be clamped for about thirty to forty-five minutes after the medicine is delivered to allow absorption. It should be noted that anticholinergic drugs ( such as Cogentin®) are currently available in intravenous formulations, and apomorphine (a potent dopamine receptor agonist) should also be available in the near future.
Q: WHAT ARE THE DANGERS IN DELAYING THE RESTARTING OF DOPAMINERGIC MEDICATIONS?
A: Post-operative recovery can be difficult under any circumstances; however, with the additional burden that PD imposes, resumption of optimal motor function as soon as possible is of paramount importance to minimize any of the following potential problems:
First, delay in reinitiating PD medications will compromise motor function, including those of the respiratory (breathing) and pharyngeal (swallowing) muscles. Compromise of respiratory muscle function can lead to poor cough and restriction of movement of the respiratory muscles (limiting deep breaths). Additionally, swallowing problems can develop or worsen without PD meds, thus increasing the risk of aspiration. These problems, taken together with the decreased ability to move about will make the common post-operative complication of pneumonia much more likely without PD medications. Secondly, the rigidity and bradykinesia brought on by lack of PD medications leads to decrease movement and thereby increases the post-operative risk of developing blood clots in the legs (deep venous thrombosis) related to the sluggish blood flow. Mobilization, a major goal following surgery of any kind, is made considerably more difficult without medication, thus further delaying rehabilitation. Finally, a rare but potentially life threatening condition known as neuroleptic malignant syndrome (NMS) must be a concern whenever dopaminergic drugs are abruptly discontinued. In NMS, mental status changes, rigidity, tremor, fever, and autonomic instability can lead to a life-threatening condition. If recognized early, treatment can be life saving.
Q: SHOULD A PD PATIENT DO ANYTHING SPECIAL PRE-OPERATIVELY TO MAXIMIZE THE POSSIBILITY OF A GOOD RECOVERY?
A: Of course, obtaining general medical clearance prior to surgery is the standard of care. Additionally, I recommend that some patients undergo a formal video swallowing evaluation as well as obtain pulmonary function tests so that baseline measures can be obtained, and thus appropriate planning for potential postoperative difficulties be instituted. Also, common medications that may alter bleeding need to be discontinued such as vitamin E, aspirin and Gingko Biloba. Maintaining good hydration and appropriate nutritional status as well as optimizing overall conditioning before surgery, maximizes the potential for a good recovery.
Q: WHAT MEDICATIONS SHOULD BE AVOIDED FOLLOWING SURGERY?
A: Needless to say, all drugs that block dopaminergic function need to be avoided. Post-operative nausea is extremely common and medications such as Reglan®, Compazine®, and Phenergan® are often considered first line medications to treat this problem. By their very nature all of these medications will worsen PD symptoms and should therefore be avoided. If treatment of nausea and vomiting is required, the drug of choice for PD patients is Zofran®. Zofran's mechanism of action does not involve altering dopaminergic function. Zofran® can be given intravenously as well as orally. Post-operative confusion and agitation are other situations where dopamine blocking agents are often employed. Older neuroleptic drugs such as Haldol® and closely related drugs should be avoided. The newer so called "atypical neuroleptics" such as Risperdal® and Zyprexa® also have a deleterious effect on the motor symptoms of PD. The drugs of choice for the treatment of post-operative delirium are Seroquel® and Clozaril®, both of which are very effective and usually have insignificant negative effects on PD symptoms.
Q: WHY ARE SO MANY PEOPLE WITH PD CONFUSED AFTER SURGERY?
A: Post-operative confusion (delirium) is usually due to a number of factors in the PD patient. Certainly, as the age of the patient increases, post-operative mental status changes become more likely. Additional factors that may play a role in post-operative delirium include pre-existing dementia, anesthetic and pain medications, change in environment and the unfamiliar medical staff. Optimal management of this situation requires treatment of the delirium without compromising motor function. Thus, as noted above, by using drugs such as Seroquel® or Clozaril®, mental status can often be treated without lowering PD medications, which can then preserve motor function. The approach of lowering PD medications to treat post-operative mental status changes usually results in marked worsening of motor status and places the patient at greater risk of aspiration, blood clots, pneumonia and further deconditioning, all of which retard recovery.
Q: SHOULD THE SURGEON TALK TO THE NEUROLOGIST BEFORE THE PROCEDURE?
A: It is not enough to have a surgeon skilled in performing a particular procedure. It is also important for the surgeon to have a good grasp of the potential difficulties that PD can impose prior to undergoing surgery. The need for on-time administration of medications as well as a knowledge of which medications to avoid are just a few of the issues that need to be understood in order to maximize the potential for a good outcome. Being prepared for post-operative changes in medication responses (unexpected dyskinesias and prolonged "off" episodes) can be more effectively dealt with when there is awareness of these potential problems. I therefore often recommend that at least a brief conversation between the surgeon and neurologist takes place so that potential pitfalls can be identified and avoided.
Dr. Rezak is the Medical Director of the APDA National Young Onset Center as well as the Director of the Movement Disorders Center and Co-Director of the Deep Brain Stimulation Program of the Neurosciences Institute at Central DuPage Hospital in Winfield, IL. Dr. Rezak is also on the Speaker's Bureau for Allergan, Novartis, Medtronic, Teva, and GlaxoSmithKline.