CARDIAC ARRHYTHMIAS<br />MEDICAL CONSIDERATIONS<br />Stress associated with dental treatment or excessive amounts of injected epinephrine may produce life threatening cardiac arrhythmias in susceptible dental patients. Patients with existing arrhythmias are at risk at dental office In addition, patients at risk for developing an arrhythmia also may be in danger in dental office if they are not identified and measures are not taken to minimize stressful situations that can produce an arrhythmia. Other patients may have their arrhythmias under control by drugs or pacemaker but require special considerations when receiving dental treatment.<br />Prevention of medical complications.<br />Patients with a history of palpations, dizziness, or syncope may have a cardiac arrhythmia and should be evaluated by a physician before a dental treatment. Patients with an irregular cardiac rhythm should be referred for medical evaluation. Elderly patients with a regular heart rate that varies in intensity with respiration should be referred for evaluation of possible sinus arrhythmias & sinus node disease.<br />Precautions include <br />
Consider the underlying cardio vascular disorder.
Patients with underlying cardiovascular disease must be identified carefully & managed as indicated by the nature of the cardiac problem.
Reduce patient anxiety. Any increase in sympathetic tone can precipitate an arrhythmia. Premedication with a short acting benzodiazepine: triazolam 0.125-0.25 mg, diazepam: valium 5 mg ,oxazepam: serax 5mg, on the night before the appointment & 5mg one hour before the appointment may be used. Nitrous oxide-oxygen inhalation sedation can be initiated. An open, honest approach with the patient to explain the procedure is important.
Minimize stressful situations. Patients with coronary atherosclerotic heart disease, ischemic heart disease, or congestive heart failure should be managed to prevent or minimize acute exacerbation of these conditions that might trigger significant arrhythmias.
Avoid excessive amounts of vasoconstrictive agents & local anesthetic considerations. The use of more than two cartridges (3.6ml) of anesthetic (containing 0.036 mg of epinephrine) is not advised for any given appointment. 1.100,000 epinephrine i.e., only a very low amount is usually used. I patients with severe arrhythmias and for short appointments use of a local anesthetic without epinephrine may be the optimal choice. Vasoconstrictors must not be used in gingival packing material for crown impressions or to control local bleeding. Intraosseous & periodontal intraligamentary injections of local anesthetics containing vasoconstrictors should be avoided. Additionally, caution should be taken when using local anesthetics containing Vasoconstrictors with patients taking digitalis.
Avoid general anesthesia: patients susceptible to developing cardiac arrhythmias should not be given general anesthesia in the dental office.
Be careful in using electrical equipment: during the medical consultation for patients with a pacemaker, the risk for electromagnetic interference from electric equipment used in the dental office. Patients with a new well shielded generator are at low risk however patients with low shielding may be at high risk. Electro surgery units can be a risk to all patients with pacemakers, and their use in these patients is not recommended.
Alter anti coagulant regimen necessary. Patients with arrhythmias may be receiving anticoagulant therapy & clinicians should determine prothrombin time ratio or the internationalized normalized ratio levels before surgery. The anticoagulant regimen need not be altered for most dental procedures. If the prothrombin time ratio is 2.5 or less or the international normalized ratio is 3.5 or less, most dental procedures can be performed without alteration of the anticoagulant regimen and use of only local methods of homeostasis.
Refer for diagnosis & management any patient identified as having signs & symptoms suggesting the presence of cardiac arrhythmiaEstablish the current status for a patient with an arrhythmia under medical treatment & the type & severity of the arrhythmia.For patients with pace makers, determine the following: Type of pacemaker, type of arrhythmia being treated, need for prophylactic antibiotic, degree of shielding provided for generator & types of electrical equipment that should be avoided.Establish whether the patient with atrial fibrillation is being treated with warfarin sodium (Coumadin) to prevent atrial thrombosis & determine the way the dosage should be altered by physician.Establish the presence & current status of any underlying condition that may be the cause of arrhythmia.<br />
Monitor for digitalis intoxication. Patients at risk for digitalis toxicity should be monitored carefully. Patients with arrhythmias medicated with digitalis may be susceptible to digitalis toxicity if they are elderly or have hypothyroidism, renal dysfunction, dehydration, hypokalemia, hypomagnesaemia or hypocalcaemia. Patients with electrolytic imbalances are more susceptible to digitalis toxicity because of the heightened sensitivity of heart to these changes accompanying certain arrhythmias. Therapeutic doses of digitalis are 0.5-2.0 ng/ml. levels greater than 2.5 ng/ml may result in digitalis toxicity. Patient’s medications and dosages should be monitored.
DENTAL MANAGEMENT-MEDICAL CONSULTATION<br />Undetected arrhythmiaRapid or slow pulse rateIrregular pulse rhythmAssociated symptoms: Palpations Dizziness Syncope Angina DyspneaSusceptibility to development of arrhythmia during Dental treatment History of ischemic heart disease History of valvular heart disease History of thyroid disease History of obstructive pulmonary diseaseUnder medical treatment for arrhythmia Antiarrhythmic medication use Implanted pacemaker.<br />PATIENT IDENTIFICATION<br />