Respiratory system
Done By: Dr. Shaimaa Hmaid Conservative Dentistry Resident
Respiratory diseaseAsthma and COPD
1
Chronic obstructive pulmonary diseaseDefinition: COPD is a
chronic,slowly progressive,irreversible disease,charecterized by
breathlessness and wheeze,cough and sputum production .Is usually a
combination of chronic bronchitis,emphysema.
Chronic bronchitis:Definition:excessive production of mucus and
persistent cough with sputum production ,daily for 3 months in a
year for more than 2 consecutive years.Sputum stagnates and becomes
infected with S.pneumonae,M.catarrahlis,H.influenzae.
EmphysemaDefinition:Dilatation of air spaces distal to the
terminal bronchioles with destruction of the alveoli reducing the
area for air exchange.
Causes of COPD:SMOKINGEnvironmental pollutionDustOccupational
exposures to chemicalsDeficiency of the aniproteolytic enzyme alpha
1-antirypsin (rare)
Clinical features:Progressive dyspnea and low oxygen saturation
accumulation of carbon dioxide(hypercapnia)Acidosiseventual
respiratory failure or Rt.sided heart failure.Early morning mucoid
cough .
COPD is complicated by chronic hypoxemia with dyspnea on
effort.Mild at first ,then deteriorates to leave respiratory
cripples ,dyspneic at restSome pts with emphysema maintain normal
blood gases by Hyperventilation pink panter,pink puffer who is
severely breathless and pink from vasodilation caused by co2
retention .
Those with chronic bronchitis, fail to maintain hyperventilation
,lose the co2 drive ,become hypercapnic and hypoxic, but less
breathless.Chronic hypoxemia leads to central cyanosis and ankle
edema and raised jugular venous pressure gives rise to blue bloated
appearance ,for whom the respiratory drive is from low po2 and thus
o2 administration is contraindicated.
diagnosisChest radiographsRespiratory function tests(Spirometry
).Arterial blood gas estimation .FEV1 is typically reduced, and is
used to grade COPD. FEV1 and if less than 40% severe COPD.FEV1:FVC
if the ratio was less than 70% confirms airways obstruction.
managementStop smokingAntibiotics
amoxicillin,trimethoprim,tetracyclin.Immunization against
influenza.Mucolytics carbocisteineBronchodilators
ipratropimbromide,antimuscarinics oxitropium or beta agonist or
occasionally lowe dose inhaled or systemic corticosteroids or
theophylline.Long term oxygen therapySurgeryLung
transplantation
Dental aspectsUpright positionDifficult to use rubber damPt on
corticosteroids should be treated with precautions.Theophylline
interactions with
:epinephrine,clindamycin,clarithromycin,azithromycin,erythromycin,ciprofloxacin
may result in dangerously high levels of theophylline.L.A
preferred, but bilateral mandibular and palatal injections should
be avoided. Analgesia only if necessary and after preoperative
assessment.
Diazepam and midazolam are mild respiratory depressants should
not be used.G.A only if necessary.I.V barbiturates are totally
contraindicated.Pt may cough and contaminate other areas of the
lung if slightly anesthetized.Spirometry and carbon monoxide
perfusion are essential to assess respiratory function.
Preoperatively: cessation of smoking for at least 1 week
Respiratory infection must be eradicated, sputum should first be
sent for culture and sensivity, but antimicrobials such as
amoxicillin should be started without awaiting results. Ipratropium
can cause dry mouth
AsthmaCommon 2-5% of the population .MalesChildhood or early
adulthood.About half of patients developed it before the age of 10
years.
Its a state of bronchial hyper-reactivity causing:Paroxysmal
expiratory wheezingDyspneaCough
Generalized reversible bronchial narrowing is caused by:
excessive bronchial s.m tone ,edema and congestion, mucus
hypersecretion and diminished ciliary clearance.
Types of asthma Extrinsic
intrinsic
extrinsicAllergic asthmaTypical in children Precipitated
by:dust, animals, molds,antibiotics,NSAIDs, milk, eggs,fish,Fruit,
nuts and some antibiotics.Asymptomatic between attacks.Usually
patient develop other allergic diseases like eczema,hay fever ,drug
sensitivities.Tends to resolve in adult life.
Extrinsic Associated with overproduction of IgE on exposure to
allergens and release of mast cell products that cause bronchospasm
and oedema.Mediators: histamine,leukotrines
prostaglandins,bradykinins and PAF(platelet activating factor).
IntrinsicNot allergic.Mast cells instability and hyperresponsive
airways.Triggered by :Emotional stress-gastro-oesophageal
reflux-vagally mediated responses.
Both extrinsic and intrinsic could be initiated by the
following:Infections(viral,mycoplasmal or fungal)ExerciseEmotional
stress Food types(nuts, shellfish,strawberriesor milk)Food
additives(tartrazine)Drugs(NSAIDs,beta blockers,ACE
inhibitors,aspirin)Fumes including cigarette smoke.
Clinical featuresDyspneaCough WheezingLaboured expiration.
Children present with repeated colds with cough, malaise and
fever at night. Nasal polyps specially in aspirin sensitive
asthmatics.Rarely, a prolonged and often life-threatening attack
refractory to treatment starts and if this persist for more than 24
h, its termed status asthmaticus and potentially lethal.
General management Chest radiographs Spirometry(important) skin
tests , which may help to identify any allergens.Blood
examination(usually raised total IgE and specific IgE antibody
concentrations).Avoidance of identifiable irritants and allergens,
use of drugsHome use of peak flow meters allows patients to monitor
progress and detect any deterioration.
DrugsBeta 2 agonists (sulbutamol)Corticostroids, if there are
daily symptoms.Leukotriene receptor
antagonists(Zafirlukast)Omalizumab(a recombinant humanized
monoclonal anti IgE antibody ) decrease the symptoms.Systemic
steroids,oxygen and hospitalization in recalcitrant disease .
Dental aspects Ask pt to bring their medications.In severe
asthmatics..defer elective ttt.Allergy to penicillin maybe more
frequent .Theophylline interactions Patients On leuokotriene
modifying drugs may have prolonged INR and bleeding tendency
.Systemic steroids treatment brings with it the risks from steroid
complication, and operation are dangerous on such patient without
adequate preparation.
Avoid the following drugs :Aspirin increases zafirlukast
levels.NSAIDsSulphites in L.A If epinephrine containing local
analgesics are indicated, thy should be given with an aspirating
syringe, but contraindicated with pt on theophyline causes
dyrhythmiasConscious sedation :Relative analgesia with NO and
oxygen is preferable over IV sedation .
Sedatives are better to be avoided .G.A is best avoided Opioids
avoided
Dental aspectsOral manifestations :-The use of corticosteroid
inhalers causes oral and pharyngeal thrush and rarely
angina,bullosa haemorrhagica. -Beta 2 agonists and ipratropium
bromide causes dry mouth .-Anti-asthmatic drugs may Lower the
salivary pH -Periodontal inflammation is more in asthmatic patients
.-Gastro-oesophageal reflux is common with tooth erosion
Acute asthmatic attack Asthmatic attacks may be precipitated
by-Anxiety:gentle handling and reassurance..-drugs which
include:Asprin ,NSAIDsBarbituratesBeta blockers Mefanamic acid
Pentazocine Acrylic monomer Colophony and cyanocrylates .
Usually self-limiting or responds to the ptn usual drugs,..beta
agonist inhaler Status asthmaticus is potentially lethal
emergency.
Thank you
