Respiratory Flashcards
CF, asthma, LRTI, upper airway obstruction, URTI, pleural effusion, FB, TB, whooping cough, OSA
Cystic fibrosis
Autosomal recessive-chromosome 7-defective chloride ion channel. Commonest mutation delta F508. Parents with a CF child have 50% chance of next child being a carrier and 25% chance of them having CF
Path: abnormal ion transport so in airways cilia impaired + mucus secretions retained, intestines thick meconium, pancreatic ducts blocked, excessive NaCl in sweat due to abnormal function of sweat gland
CF: in the neonate meconium ileus (vomiting, distention, failure to pass), prolonged jaundice; infancy growth faltering/recurrent chest infection/malabsorption/steatorrhoea; young children bronchiectasis/rectal prolapse/nasal polyps/sinusitis; older children/adults allergic bronchopulmonary aspergillosis/DM/cirrhosis/portal HTN/distal intestinal obstruction/pneumothorax/recurrent haemoptysis/male infertility
Diagnosis: newborn blood spot test, sweat test for [NaCl], confirm with genetic testing
Management: chest PT at least BD to clear secretions (young children parents do percussion + postural drainage, older children controlled deep breathing exercises + PT devices), nebulised hypertonic saline/DNAse to reduce mucus viscosity, azithromycin (reduces exacerbations), regular IV Abx for severe infections, oral pancreatic replacement therapy (creon), high calorie diet, fat-soluble vitamin supplements (ADEK)
Complications: diabetes, liver disease, distal intestinal obstruction (helped by laxatives), atypical chest infections (often need segregation from other CF pt so they don’t pick up each other’s unusual organisms), males usually infertile (absence of vas deferences, can father children through intracytoplasmic sperm injection), psychological (is ultimately a fatal illness + management is gruelling)
Asthma-chronic
Path: genetic + environment + atopy –> bronchial oedema/mucus/infiltration with cells like eosinophils etc –> bronchial hyper responsiveness –> reversible airway obstruction –> symptoms
CF: sx worse at night/early morning, non-viral triggers, interval symptoms between acute exacerbations, personal/FH of atopic disease, respond to asthm therapy. Suspect in kids with >1 occasion of wheeze esp if interval symptoms present. Usually no signs between attacks, may have generalised wheeze/hyperinflation/prolonged expiration if bad; check for allergic rhinitis + eczema + signs of infection
Ix: clinical + skin prick testing if suspecting an allergy + PEFR/spirometry (PEFR less sensitive but most kids >5 can do it, spirometry depends, try response with bronchodilator)
Management of chronic asthma
Step up if having more sx, using reliever more than twice a week, night sx, exacerbations in past 6m (needing hospital or oral steroids)
- All-SABA (alone if infrequent short-lived wheeze)
- Regular preventer with v low dose ICS, or LRTA if <5y
- Add on LRTA (if <5y) or LABA (if 5+y)
- If no response to LABA then stop it and increase ICS to low dose; if some response then continue + increase ICS to low dose; or also keep them both + add LRTA
- Increase ICS to medium dose or add a fourth drug e.g. SR theophylline. Refer to specialist!
- Daily low dose steroid + medium ICS + refer obv
General: allergen avoidance, smoke free home. In children pressured MDI + spacer preferred, face mask until they can breathe properly with spacer. Could try breath-actuated e.g. Autohaler (less coordination than an MDI without spacer), dry power inhaled (4+ years, need good inspiratory flow so not in severe), nebuliser in any age in an acute asthma
Prescribe with brand name so not given unfamiliar inhaler device
Acute asthma features by severity
Moderate:talk, sats >92%, PEFR >50% of best, RR (<40 for 2-5y, <30 for 5-12y, <25 for 12-18y), HR (<140 for 2-5y, <125 for 5-12y, <110 for 12-18y), increased WOB (neck muscle palpation best indicator)
Acute severe: sats <92%, PEFR 33-50%, can’t complete sentence in 1 breath/too breathless to talk or feed, HR >125 (>5y)/>140 (1-5y), RR >30 (>5y)/>40 (1-5y)
Life-threatening: sats <92%, PEFR<33%, silent chest (wheezing reduces with more obstruction), cyanosis, poor resp effort, hypotension, exhaustion, confusion
(fall in HR in life-threatening is pre-terminal)
Acute asthma management
Mild-moderate/at home: give one puff SABA every 30-60s, up to maximum to 10s. If severe sx continue giving whilst wait for help
If <94% sats with high flow O2
Bronchodilators: inhaled beta2 agonist (nebulised if severe), if needed mix with ipratropium bromide, repeated doses, consider adding magnesium sulphate
Oral steroids: up to 3d usually but obv depends on how long they recover over. IV if vomiting
2nd line treatment: single bolus of IV salbutamol if not responding to inhaled, consider aminophylline if max salbutamol + ipratropium used, consider IV magnesium sulphate
Bronchiolitis
Babies 1-9m mostly, annual winter epidemics, 80% caused by RSV (rest many viruses inc parainfluenza/influenza/rhinovirus/adenovirus). If >1 virus infecting them may be more severe
CF: coryza, dry wheezy cough, increasingly WOB, feeding difficulty, high RR+HR, signs of increased SOB, hyper inflated chest (prominent sternum, liver displaced down), fine end-inspiratory crackles. may lead to recurrent apnoeas
Ix: pulse oximetry. Only do CXR/blood gas if suspect resp failure
Admit if: apnoea reported/seen, persistent sats <90% OA, inadequate fluids (<75% of normal), severe resp distress (e.g. grunting, marked recessions)
M: supportive! Humidified O2 if low sats, monitor, may need NG/IV fluids. No evidence for other treatments tho salbutamol nebs often given. May need CPAP
Prognosis: most recover within 2w but up to 50% recur or get cough+wheeze again, tend to get worse before better
Comp: bronchiolitis obliterans (rare, permanent damage after adenovirus infection)
Prevention: IM palivizumab (monoclonal antibody to RSV) for high risk preterms (but v expensive + high NNTT)
Wheeze - asthma, viral or multiple trigger
Viral episodic wheeze: cause in most wheezy preschool children. Coryzal virus - narrowed + obstructed small airways. RF are maternal smoking + prematurity (not FH, atopy). Usually resolves by 5y as airways grow
Multiple trigger wheeze: preschool + school age. Triggers include viruses, cold air, dust, exercise. Many benefit from asthma preventer therapy, may get asthma astray grow
Atopic asthma: recurrent wheeze, sx between infections, evidence of allergy to inhaled allergens. Ig-E related, strongly a/w other things like eczema/food allergy + FH
Non-atopic asthma: small % of those with persistent wheeze
Pneumonia
Often no cause found, viruses more in younger children (esp RSV) + bacteria more in older (Mycoplasma pneumonia, Strep pneumonia), GBS in newborn from mother’s genital tract. Consider M TB. Hib used to be in younger kid but reduced w vaccine
CF: usually URTI, then fever cough rapid breathing lethargy poor feeding. Some have no cough. Neck/chest/abdo pain may be pleural irritation. Classic consolidation signs often absent in young children
Ix: CXR to confirm, NPA
M: admit if <92%/concerning features, supportive (analgesia for pain, O2 if low, correct dehydration). Abx depend on age + severity - newborn need IV broad spec, older infants oral amoxicillin/co-amoxiclav, >5y amoxicillin/erythromycin (Mycoplasma - erythromycin). Drain effusion if not resolving
Comp: pleural effusion, empyema, sepsis
Chronic lung infection
Persistent wet cough consider
Persistent bacterial bronchitis-H influenza or Moraxella. Give longer course Abs e.g. 4w + physio, as can cause bronchiectasis if untreated
Primary ciliary dyskinesia: impairs mucociliary clearance causing recurrent URTI+LRTI. CF recurrent productive cough, purulent nasal DC, chronic ear infections. 50% have dextrocardia + situs invertus (Kartagener syndrome)
Immunodeficienc: may p/w severe/unusual chest infections, secondary to illness/HIV/meds or primary e.g. IgG deficiency
Croup
Usual cause parainfluenza virus (can be others), most common in 2yos, most common in autumn. Onset over days
CF: coryza + fever, hoarseness, barking cough (due to tracheal oedema+collapse), harsh stridor, difficulty breathing with chest retraction, often worse at night
Categories:
- Mild: occasional barking cough, no stridor audible at rest, no/mild recessions, child happy and normal tbh
- Moderate: frequent barking cough, stridor audible at rest, suprasternal + intercostal recessions at rest, no/little distress
- Severe: frequent barking cough, prominent inspiratory/biphasic stridor at rest, marked recessions, sig distress/lethargy, tachycardia
M: oral dexamethasone/prednisolone, or nebulised budesonide; in severe nebulised adrenaline + oxygen
Acute epiglottitis
Swelling of epiglottis, a/w sepsis, no preceding coryza, onset over hours. Caused by Hib so rare now. V different management to croup so must diagnose.
most common in 1-6y
CF: v ill, high fever, soft inspiratory stridor, muffled/reluctant to speak, not able to drink, no cough/slight, increased WOB, child sits immobile + upright with mouth open to optimise airway: don’t examine throat-may precipitate total airway obstruction
M: urgent admission with anaesthetist + ENT surgeon. Intubate under GA + sepsis 6 + cefuroxime IV. Most recover in 2-3d, rifampicin for household contacts
Bacterial tracheitis
Pseudomembranous croup
Rare but serious, caused by S aureus usually
CF: high fever, appears v ill, rapidly progressive airway obstruction w copious thick secretions
M: IV Abx, +/- intubation + ventilation
Chronic stridor
Upper airway obstruction from a structural problem causing narrowing/collapse e.g. subglottic stenosis, laryngomalacia (floppy larynx) or external compression by LN/tumour
Coryza
Clear/mucopurulent dc, nasal blockage. M-paracetamol, ibuprofen. Cough may persist for up to 4w
Sore throats
Pharingitis: inflammation, tender local LN, usually viral but in older kids may be group A strep
Tonsillitis: intense inflammation of tonsils, often purulent exudate. Organism include group A beta haemolytic strep, viruses, EBV (IM). Can’t really tell if viral or bacterial but things ike headache/apathy/abdo pain/white exudate/cervical LN point to bacterial
M: fluids + rest, Pen V for 10d if likely bacterial (FeverPAIN score)
Avoid amoxicillin as can cause widespread macuopapular rash if its IM
Comps-hospital admission for rehydration, peri tonsillar abscess
