Systemic Conditions that May Affect Oral Surgery (lecture 1)

stable angina pectoris

chest pain caused by ischemic heart disease - O2 supply to myocardium < O2 demand.

Usually due to coronary artery disease.

Infrequent pain occurs predictably following exertion & is relieved by rest or nitroglycerin.

R & L coronary arteries, L anterior descending artery, circumflex artery

The 4 coronary arteries that may be damaged in ischemic heart disease.

aortic stenosis

narrowing of the aorta that may cause myocardial ischemia.

coronary embolization

obstruction of coronary artery by a clot (may be formed by coronary thrombosis) or other object, resulting in myocardial ischemia.

older men (over 40)

Most vulnerable age group for angina pectoris.

substernal, epigastric, retrosternal (radiating to L arm, back, shoulder, neck, mandible)

Locations for the pain during angina pectoris.

B blockers, Ca channel blockers

Drugs used for angina pectoris to decrease HR & contractility and to increase vasodilation.

nitroglycerin

Vasodilator that relieves pain effectively for stable angina.

unstable (pain is more frequent and requires medication to relieve)

If pain occurs at rest, then the angina is classified as (stable/unstable).

Avoid elective tx.

0.04 mg (about 2.35 cartridges of 1:100,000 LA)

Epinephrine limitation for pts with angina pectoris. Keep epinephrine low to decrease myocardial oxygen demand.

benzodiazepine (Triazolam, diazepam)

Drugs that decrease anxiety before surgery. Use as part of anxiety reduction protocol.

nasal cannula (delivers O2 @ 3 mL/min) , nitroglycerin (vasodilator)

2 tools for increasing a pt's O2 supply (helps prevent/relieve angina pectoris)

Both should be readily available for a pt with a history of myocardial infarctions.

In the case of an episode of angina pectoris, give pt a dose of nitrate every ___5_______ minutes. If a __3rd______ (number) dose is needed, call EMS and assume a myocardial infarction is occurring.

In the case of an episode of angina pectoris, give pt a dose of nitrate every __________ minutes. If a ________ (number) dose is needed, call EMS and assume a myocardial infarction is occurring.

myocardial infarction

Necrosis of heart muscle b/c of ischemia.

Risk factors include smoking, high cholesterol/blood pressure/weight, diabetes, stress.

Damaged tissue is prone to dysrhythmias.

Unlike angina, pain is NOT relieved by rest, nitrates, or O2.

hypotension (drop in blood pressure; pt turns clammy & gray)

During a myocardial infarction, expect (hyper/hypo)tension.

1 month

After an uncomplicated myocardial infarction, defer elective surgery for at least _________________.

Follow 0.04 mg epinephrine limitation.

Complex MI are associated with heart failure, dysrhythmia, & inflammatory pericarditis - defer surgery if symptoms exist for longer than this time period.

aspirin

Medication that reduces clotting effects & reduces risk of coronary thrombus. Use for pts with history of ischemic heart disease.

Do not have low risk pts stop taking it. Have high risk pts stop taking it 5-7 days before surgery to minimize bleeding risk.

congestive heart failure

failure of disease myocardium to deliver the cardiac output needed by the body (or when a healthy heart can't meet extreme demand), resulting in a buildup of blood in vascular beds.

Follow 0.04 mg epinephrine limitation.

dyspnea

difficulty breathing - symptom of congestive heart failure

orthopnea

difficulty breathing when lying down - symptom of congestive heart failure

ascites

abnormal accumulation of fluid in the abdomen - symptom of congestive heart failure.

decrease blood pressure

Goal of many tx for congestive heart failure. May use ACE inhibitors, ARBs, beta blockers, diuretics, or low sodium diet.

Over 130 systolic or 80 diastolic

definition of hypertension

90/60

Below this BP reading is considered hypotension

180 systolic, 120 diastolic (add up to 300 or more)

Definition of a hypertensive crisis.

May be asymptomatic.

Consult PCP before elective surgery, avoid IV with Na+, limit epinephrine to 0.04 mg

stage 1 hypertension

130-139/80-89 blood pressure

stage 2 hypertension

>160/>100 blood pressure.

Wait 5 min & reassess.

1 month, premed is NOT usually necessary (same for coronary artery stent)

For a coronary artery bypass graft, delay elective surgery for at least ____________, and antiobiotic prophylaxis (is/is not) necessary.

premed is necessary for prosthetic heart valves.

For cardiac valve replacement, premed (is/is not) necessary

False (keep the pt on anti-clotting meds to avoid a stent thrombosis)

For high-risk pts, consider cessation of aspirin 5-7 days prior to surgery.

T/F: For a pt with a coronary artery stent, stop antiplatelet aggregation therapy (aspirin) or vit K antagonists (Coumadin) before surgery to make sure the pt does not bleed too much.

The stent itself may be impregnated with a drug.

4-6 weeks; 6-12 months (wait this long before elective surgery)

A bare metal stent requires ____________ for endothelialization, while a 2nd-generation drug-eluting stent requires __________________ for endothelialization but are less vulnerable to restenosis (artery narrowing again).

Greatest risk of restenosis occurs during endothelialization of the stent.

thienopyridine (Plavix)x, aspirin

Dual antiplatelet therapy required for coronary stents. Do NOT discontinue before surgery - need to minimize risk of thrombosis & restenosis.

plavix (thienopyridine)

Drug that prevents ADP from binding to platelets (P2Y12ADP receptor antagonist), thereby stopping platelet aggregation during clotting.

NOT monitored with INR or PT test.

Monitor with aggregometry & VASP phosphorylation test.

ischemic stroke

The more common form (87%) of stroke. Occurs as a result of a blocked cerebral vessel caused by a thrombus (stationary clot) or embolus (mobile clot).

Unilateral numbness/weakness, confusion, impaired speaking/seeing/walking/balance

hemorrhagic stroke

The less common form of stroke caused by cerebral arterial bleeding. Hypertension, trauma, or anticoagulation can cause this.

Watch for sudden, severe headache, confusion, nausea, vomiting, neck/shoulder pain, seizures, and loss of consciousness.

6 mo

after a stroke, delay elective surgery for ________________.

False (premed is generally used for pts with prosthetic heart valves)

T/F: Pts with internal cardiac defibrillators and pacemakers must take premed to prevent bacteria from colonizing the prosthesis.

cardiac defibrillator (automatic internal cardiac defibrillator)

Device that monitors malignant tachyarrhythmias & stops them with an electric shock.

High freq electromagnetic interference may inhibit the device, while low freq electromagnetic interference may activate it (watch out for MRIs, shivering, cell phones, and magnets)

pacemaker

Device that detects heart rhythm and signals the heart to beat if the SA or AV node fails.

aspirin & NSAIDS

drugs that can trigger an asthma attack.

B2 agonist (e.g. albuterol)

mechanism of action of an asthma inhaler (bronchodilation).

Can also use corticosteroids.

-umab

Suffix for biologic medication (injected human monoclonal antibodies) used as targeted drug therapy for asthma - reduce inflammation & improve breathing

COPD (chronic obstructive pulmonary disease)

Disease that obstructs airflow in lungs b/c of either chronic bronchitis or emphysema.

Look for dyspnea (hard to breathe) during exercise, thick mucous, coughing, respiratory infections, barrel chests, wheezing, and pursed lips while exhaling.

Treat w/bronchodilators, corticosteroids, or supplemental O2.

chronic bronchitis

Cause of COPD - onset around 50 yrs, mucous-laden cough, "blue bloater" (overweight & hypoxic), high PCO2 and low PO2, frequent respiratory infections

emphysema

Distension & loss of elasticity of alveoli resulting in COPD.

Onset at 60 yrs, "pink puffer" (skinny barrel chest & difficulty expelling air), few respiratory infections, low levels of mucous, normal PCO2 and low PO2, no hypoxia

corticosteroids

Anti-inflammatory medications for asthma & COPD that may cause adrenal suppression as a side effect.

C (do NOT give high dose O2 since pt relies on low arterial PO2 to stimulate breathing. A higher arterial PO2 will decrease the pt's drive to breathe)

For a pt with COPD, which of the following should NOT be done?

A. Sit pt semi-upright to help remove mucus.

B. Stop any respiratory depressant drugs

C. Give lots of supplemental O2.

D. Have a bronchodilator on hand.

high PCO2 for normal pts, low PO2 for COPD drives respiration.

Normal pts rely on (pCO2/PO2) to stimulate breathing, but COPD pts rely on (pCO2/PO2) to drive respiration.

hyperkalemia (high K+)

Complication of chronic kidney disease that can impair heart function.

6-24 mg/dl

normal range for blood urea nitrogen test (BUN). Higher levels can indicate kidney disease.

1.3 mg/dl

A creatinine level above this may indicate kidney disease.

Creatinine is a byproduct of protein metabolism removed from circulation by the kidney.

heparin

Anticoagulant that is gone from the pt's bloodstream several hrs after dialysis - this is why it's best to wait to do surgery the day AFTER dialysis.

True (transplant pts are often on immunosuppression drugs)

T/F: Consider antibiotic prescription for pts with renal transplant.

gingival hypertrophy

Oral side effect often caused by immunosuppressive drugs taken by pts with transplants.

jaundice (icterus)

Symptom of hepatic disease that presents as yellow scleras as bilirubin builds up in the blood.

II, VII, IX, X

4 vitamin K dependent clotting factors - production is decreased during hepatic disease, leading to increased prothrombin time.

thrombocytopenia

Portal hypertension during hepatic disease can result in an enlarged spleen (hypersplenism) that reduces the number of platelets, leading to this condition.

antiseizure

What type of medications are these? Phenotyoin (dilantin), carbamazepine (Tegretol), levetiracetam (Keppra), clonazepam (Klonapin), gabapentin (Neurontin).

Use anxiety-reduction protocol.

hyperthyroidism

Excess T3 & T4 - often results in goiter.

Treat with radioactive iodine (kills thyroid cells) or thyroidectomy. Watch out for high pulse and BP. Limit epinephrine.

Grave's disease

Hyperthyroidism resulting from autoimmune disease. Usually seen in younger women; entire thyroid enlarges.

Look for exophthalmos (bug eyes) and hypermetabolic state.

nodular goiter

The most common type of thyroid lesion. Seen in older women. Abnormal cell growths form lump(s) in enlarged thyroid gland.

thyroid storm

Sudden release of T3/T4 after stress, infection, or catecholamine release. Presents as high systolic BP, tachycardia, fever, delirium, & restlessness.

2nd trimester

Ideal time of pregnancy for oral surgery if surgery can't be delayed until after birth.

Keep radiographs to a minimum.

Don't recline pt all the way supine to avoid pressure on inferior vena cava & bladder.

inferior vena cava (hypotension/tachycardia), bladder (urinary urgency)

2 anatomical structures that may be compressed if a pregnant woman is reclined too far for too long during treatment.

beta blockers, Ca channel blockers, nitrates, aspirin

4 medications used for ischemic heart disease.

Ideally pt should not halt medication before, during, or after surgery

ACE inhibitors, ARBs (angiotensin receptor blockers; may be combined with Neprilysin inhibitor)

2 classes of drugs that optimize heart fxn by promoting vasodilation & decreasing blood pressure.

Use for pts with congestive heart failure.

digoxin

drug that increases contractile force of heart & slows electrical conduction through the AV node.

Useful for pts with congestive heart failure.

hypertensive urgency

A hypertensive crisis (180/120 or higher) that does NOT cause acute organ damage.

Pt should continue antihypertensive meds before & after tx.

hypertensive emergency

A hypertensive crisis (180/120 or higher) that involves life-threatening complications (acute organ damage): stroke, MI, kidney damage, or aortic dissection.

Pt should continue antihypertensive meds before & after tx.

coumadin

Vit K antagonist used as an antiplatelet aggregation drug.

chemotherapy (decreases endothelial hyperplasia), immunosuppressive (decreases inflammation)

The 2 categories of drugs used to coat drug-eluting stents (make up 90% of stents placed annually in the U.S.; the other 10% are bare).

The drug is impregnated into the framework of the drug-eluting stent, while the polymer coating of the stent controls the drug's release.

restenosis

Biggest risk of having a stent. Caused by thrombus (blood clot).

Best to delay elective tx until after endothilialization (6-12 mo. for drug-eluting stents)

thrombus

a blood clot attached to the interior wall of an artery or vein

embolus

A clot that breaks lose and travels through the bloodstream.

1. Allergens

2. Aspirin/NSAIDs

3. Occupational factors

4. Infections

5. Exercise

6. Stress

6 things that can trigger an asthma attack

leukotrienes

Inflammatory molecules whose release is triggered by airborne allergens. These molecules activate and attract neutrophils and eosinophils, promote bronchoconstriction, and increase mucus production (worsen asthma attacks).

epinephrine

Sympathomimetic amine that can alleviate asthma by triggering bronchodilation.

PCO2 (bronchitis --> high CO2 and low O2 b/c dyspnea inhibits gas exchange)

A pt with chronic bronchitis has a high (PCO2/PO2)

PO2 (emphysema --> low O2 and normal CO2 b/c damaged alveoli inhibit gas exchange but hyperventilation can maintain CO2 levels)

A pt with emphysema has a low (PCO2, PO2).

Normally not too severe relative to bronchitis.

alcohol withdrawal, fever, hypoglycemia, traumatic brain injury

4 causes for seizures.

May frequently have unknown cause.

PCO2

A pt with chronic bronchitis has a high (PCO2/PO2)

1. Coronary artery obstruction (spasm, stenosis, thrombus, embolus)

2. BP reduction (hypovolemic/hypotensive shock)

3. Anemia

4. Ventricular hypertrophy

List the 4 causes of ischemic heart disease (myocardium can't get enough O2)

prevention (get health hx)

Best tx for angina pectoris

exercise, anxiety (stress), pain

What situations increase myocardial oxygen demand, increasing the risk that a pt has an episode of angina pectoris?

1. Anxiety reduction protocol (benzodiazepine, non-pharmacologic, post-op instructions/expectations)

2. Profound LA

3. 0.04 mg epinephrine limitation

3 strategies for decreasing myocardial O2 demand.

1. Angina history

2. Chest pain (unstable angina)

3. Pain not relieved w/rest, nitrates, or O2

4. Dysrhythmia

5. Hypotension

6. Shock (turns cold, clammy, gray)

7. Denial (says everything is ok)

7 symptoms of an acute myocardial infarction.

Also may be observed when starting an OMFS exam.

1. hypertension

2. coronary artery disease

3. cardiomyopathy (diseased heart muscle)

4. valvular disease

5. congenital heart disease (structural defects)

5 causes of congestive heart failure

1. Fatigue

2. Dyspnea (difficulty breathing)

3. Orthopnea (difficulty breathing when lying down)

4. Paroxysmal nocturnal dyspnea

5. Pulmonary/pedal edema

6. Weight gain (fluid retention)

7. Ascites (distended abdomen)

7 symptoms of congestive heart failure.

Give supplemental O2, avoid supine position, & limit epinephrine.

supplemental O2, nitric oxide

Give these 2 things to a pt who is having a stroke (cerebral vascular accident)

1. Infection (viral hepatitis)

2. Substance abuse

3. Vascular congestion

3 causes of hepatic disease