cardiovascular DISEASE, RESPIRATORY DISEASE AND THE ORAL CAVITY Flashcards
How is infective endocarditis prevented?
Prophylactic antibiotics. Only given to very particular people (immunocompromised, people with prosthetic heart valves, rheumatic heart disease)
Which cardiac conditions require antibiotic prophylaxis?
Prosthetic cardiac valve, including transcatheter implanted prosthesis or homograft
Prosthetic material used for cardiac valve repair such as annuloplasty rings and chords
Previous Infective endocarditis
Congenital heart disease only if it includes (Unrepaired cyanotic defects, or repaired defects with residual defects at or adjacent to site of prosthetic patch or device)
Rheumatic heart disease (high risk patients)
What should you consider when giving AB prophylaxis?
The risk of giving the antibiotic,
The risk of the patient developing endocarditis from the procedure,
The risk of a potential adverse outcome if the patient does develop endocarditis.
What should be done for patietns with cardiac abnormalities regardless of if AN prophy is indicated?
All patients with cardiac abnormalities should be reminded to practice good oral hygiene and have regular dental check-ups (Minimum 6 monthly)
Refer for investigation of unexplained fever ASAP
What is the difference between pharmacokinetic and pharmacodynamic drug interaction?
Pharmacodynamic interactions are those that modify the pharmacological effect of a drug without altering its concentration in the tissue fluid. This means that the effect of one drug is changed by the presence of another drug at the same molecular site.
Pharmacokinetic interactions are are those that alter the concentration of a drug that reaches its site of action. Therefore, one drug alters the concentration of another drug in the system (either an increase or decrease). This modification could occur at any phase of the drugs life inside you absorption, distribution, metabolism or excretion of the drug
How does aspirin work?
Aspirin inactivates COX enzymes required for thromboxane and prostaglandin synthesis.
Irreversibly inhibits COX1 and modifies enzymatic activity of COX2.
How do NSAIDs and Aspirin interact?
NSAIDs antagonise aspirin (competitive agonist)
Shared binding site on COX-1 on platelet
Patient studies show that >3 days ibuprofen negates cardioprotective effect of aspirin
If you absolutely NEED to give NSAIDs to someone one aspirin what is the best NSAID to give?
Naproxen
What is clopidogrel used for?
It is an antiplateley drug used in primary care. Given to prevent thrombosis after placement of coronary stent.
What are the adverse outcomes of using clopidogrel with NSAIDs?
When a patient takes aspirin or clopidogrel with NSAIDs there is a chance of gastric bleeding proportional to time on NSAIDs.
Unclear whether clopidogrel exerts independent injuries effect on GI mucosa or whether merely induces bleeding in already damaged mucosa (NSAIDs damage mucosa and combined antiplatelet effects)
How can adverse effects of combining clopidogrel, aspirin or NSAIDs be prevented?
PPIs can be prescribed to provide gastric protection.
What interactions besides NSAIDs does clopidogrel have?
Macrolide antibiotics
Azole antifungals
Due to cyp450 inhibition
How does warfarin work?
The mode of action is the inhibition of vitamin K‑dependent clotting factors factors II, VII, IX and X.
What interactions does warfarin have that should be noted?
One potential interaction is with broad spectrum antibiotics where Vitamin K depletion can occur. This depletion ultimately has a detrimental effect on the clotting cascade as without Vitamin K to much Warfarin is biologically active potentially increasing a patient INR.
Metronidazole: This drug comprises over 20% of all drugs prescribed by GDPs and thus there is a relatively high potential for an interaction. There have been several reports of significant bleeding in patients taking warfarin with concomitant use of metronidazole
Macrolide antibiotics: Evidence suggests that increases in INR are detected in patients who were previously stabilised on warfarin, when simultaneously given a macrolide
Azole antifungals: there are now several reports of oral miconazole gel interacting with warfarin in the systemic circulation, confirming that the gel can be absorbed with potentially harmful interactions
NSAIDs and aspirin: Compete with plasma binding proteins leading to more pharmacologically active warfarin causing much higher INR.
How can the interaction of warfarin with ABs be managed?
Monitor INR if AB is taken for >5 days
Avoid in susceptible patients
What theory explains metronidazole’s interaction with warfarin?
Metronidazole’s metabolism and its specific effect on warfarin are not as clearly defined. Metronidazole has been reported to have a stereoselective inhibition of S-warfarin metabolism which suggests possible inhibition of CYP2C9, the enzyme responsible for S-warfarin metabolism.7,8 Inhibition of CYP2C9 by metronidazole would delay metabolism of S-warfarin; this would lead to an enhanced anticoagulant effect and increase the potential for bleeding complications.
What are the clinical recommendations when metronidazole is absolutely unavoidable?
Liaison with the patient’s GMP is essential before any treatment and under no circumstances should the GDP modify the patient’s warfarin medication dosage.
Generally the doctor would reduce warfarin by approximately 1/3rd to 1/2 of current dose
When should INR be taken?
On the day or afternoon before the extraction.
Advise to keep NSAIDs to a minimum and report heavy/continuous bleeding.
What are the types of antihypertensive drugs that can be prescribed?
Diuretics
Calcium Channel Blockers
ACE inhibitors
beta-blockers
Angiotensin II antagonists
How do beta blockers and adrenaline interact?
When nonselective beta blockers are given they block the vasodilation action and the adrenaline given increases vasoconstriction. This leads to unopposed alpha vasoconstriction.
This can lead to hypertensive crisis. This isn’t true for most people but patients with BP above 200/115 should be given minimal anaesthetic.
What are the clinical recommendations with patients that have hypertension?
Track patient’s BP when suspected to be high
Routinely use infiltrations where possible.
When doing nerve blocks remember to aspirate and keep lidocaine dosage to less than 3 carpules.
Switch to adrenaline-free anaesthetics if more than 3 injections are required.
How do diuretics interact with NSAIDs?
Increased systolic pressure: Patients using diuretics for the treatment of hypertension an increase in the systolic pressure of 10mm could occur with short term the use of over the counter NSAIDs – ibrufen for example.
Congestive heart failure hospitalisation: 23.3 per 1,000 hospitalisations for Congestive Heart Failure were due to patients using diuretics with concomitant use of NSAIDs. (Heerdink et al 1998) Findings supported with more recent works (White 2007, Ejaz et al 2004)
Why do NSAIDs increased BP in patients on diuretics?
Prostaglandins are reduced leading to reduced renal perfusion: this decreased renal perfusion can cause trouble for patients who use diuretics for hypertension
How should patients deal with concomitant use of diuretics and NSAIDs?
Avoid long term use of NSAIDs and have patients monitor BP AM and PM.
What interactions do calcium channel blockers have in the dental setting?
Potential interaction with macrolide antibiotics: Calcium channel blockers like a plethora of drugs are metabolised by the liver isoenzyme P450 . Macrolide antibiotics are inhibitors of this enzyme causing an increase in the serum concentration of CCBs and a prolonged and dangerous hypotensive effect when patients take them together.
What clinical recommendation should be given far patients taking CCBs?
No macrolide antibiotics.
some reports of interaction with itraconazole, ketoconazole, and filidipine
Which dental procedures are low bleeding risk?
Supragingival scaling
Simple restorations
Orthodontic procedures
Periodontal probing
LA injections
Which dental procedures are high bleeding risk?
Extensive surgery
Apicoectomy
Alveolar surgery including bone removal
Multiple extractions
Periodontal flap surgery
What must be considered for patients following medical history?
Medication
Bleeding risk
TT and INR
WCC (Healing time affected by this)
Essential to have more than 0.5 WCC.
What are the recommendations with aspirin?
Do not cease because effects of cessation much longer to kick in than viable (7 day half life)
Warn of bruising
Local measures
What are the recommendations with clopidogrel?
Cannot tolerate aspirin don’t prescribe if patient isn’t already on it.
Do not stop clopidogrel without consulting the cardiologist.
DO NOT CEASE
COUNSEL REGARDING THE BRUISING
LOCAL MEASURES
What are the recommendations with warfarin?
Get detailed history including INR, dose/regime, and underlying medical conditions.
Organise INR afternoon before or morning of the procedure. <2.2 proceed, 2.2 - 4.0 tranexamic acid mouthwash, and >4 do not proceed
DO NOT CEASE WARFARIN
What novel oral anticoagulants are being used?
Dabigatran (Anti thrombin)
Rivaroxaban (Factor Xa inhibitor)
Apixaban (Factor Xa inhibitor)
What are the indications for dabigatran?
Prevent arterial and venous thrombosis post surgery (knee/hip replacement)
Prevent thromboembolism/stroke in non-valvular AF.
What are the indications for rivaroxaban and apixaban use?
Prevent arterial and venous thrombosis post surgery
Prevention of thromboembolism/stroke in non-valvular AF
Treatment of and prevention fo recurrent DVT and PE
How are low to moderate bleeding risk patients managed?
Similar management to warfarinised patient with INR <4
Do not cease drug
Coagulation screening is not routinely required but recommended.
Local measures for haemostasis
Multiple simple extractions are relatively safe (up to 3 teeth) Assess bleeding after tooth removal.
Defer elective procedures on patients who are on NOAC for short course.
With high risk rocedures how are NOACS used?
Discuss with physician managing anticoagulation
high TE risk - bridging anticoagulant is likely required.
Specialist or hospital setting may be needed
Coagulation screening required
With normal renal function the drug is temporarily ceased for 24 hours
If there is abnormal renal function the drug is temporarily ceased for 48 hours prior.
NOAC is restarted 48 - 72 hours after operation.
What should be done if there is local haemostatic failure?
Refer as emergency to hospital
How can bleeding be controlled locally?
Firm pressure
Assess blood loss
Infiltrate the site of bleeding with LA W/ vasoconstrictor
Pack w/ haemostatic agent
Suture bleeding point
Tranexamic acid protocol
Diathermy, cauterising agent
Arrange transport to emergency department
How is bleeding controlled during and after surgery?
Irrigate socket with TA using disposable syringe
Fill socket with loosely packed haemostatic agent.
Suture (1 per socket)
Get patient to bite on gauze soaked in TA.
After surgery:
Give patient MW/tablet with instructions on how to make and have them rinse.
Tranexemic acid mouthwash after
How should patients with coronary heart disease be treated?
Check medications
Ensure current condition is stable before elective dental procedures
Defer elective dental procedures for 3 months after MI, stent placement, or coronary artery bypass surgery.
Pacemakers or cardiac devices no problem.
How should patients with angina be treated?
Bring medications
Short appointments
Use relaxation techniques (sedation/anxiolytics)
Effective LA
When and how should pateitns with congestive heart failure be treated?
Dental treatment only if condition is stable
Short appointments
Head remains higher than the heart during treatment
Avoid NSAIDs
What is asthma?
Chronic inflammatory disorder of the airways associated with hyper-responsiveness of the lungs
How is asthma treated?
Preventers and relievers
Preventers include: Inhaled corticosteroids, long acting beta-2 agonists, oral prednisolone, and sodium cromoglycate
Relievers include short active beta-2 agonists, salbutamol, and terbutaline
How should patients be treated if they have asthma?
Avoid triggering asthma
Bring inhalers to apptmt
No in chair IV sedation
Adrenal crisis prevention
Aspirin and NSAIDs should be avoided and used cautiously
Pseudomembranous candidiasis is possible so keep that in mind.
Asthma attack during treatment should be treated as an emergency
What is COPD?
Chronic Obstructive Pulmonary Disease characterized by airway obstruction that is not fully reversible.
Usually combination of emphysema and airway damage.
Middle aged to elderly patients
Usually a history of smoking
What is obstructive sleep apneoa?
Disturbed sleep caused by episodes of apnoea (cessation of breathing)
and hypopnea (partial obstruction)
Can be mild (5 - 15), moderate (15 - 30), or severe (30+)
What are the concequences of obstructive sleep apnoea?
CVD (Coronary artery disease, MI, dangerous arrhythmias, hypertension, TIA)
Accidental death
Depression, and anxiety
How is obstructive sleep apnoea managed?
Behavioural intervention (weight loss, smoking cessation, alcohol avoidance, drug avoidance, and sleeping habit changes)
Treatment of nasal congestion
Tonsillectomy (UPPP)
CPAP
Mandibular advancement surgery
Orthognathic surgery
How can dentist treat obstructive sleep apnoea?
fabrication of mandibular advancement devices.
This has to be done with other health professionals
Should be some liason with specialist respiratory physician or sleep consultant
What are the AASM recomendation?
Sleep physicians prescribe the oral appliances
When prescribed qualified dentist makes custom titratable appliance
Sleep physician then conducts sleep study to assess MAD efficacy.
