3- acute respiratory failure Flashcards
what are some upper respiratory tract infections?
- common cold = coryza
- sore throat = pharyngitis/laryngitis
- sinusitis
- epiglottitis
why do you get a cold in winter?
virus proliferates during cold weather and winter time that gives you the cold
what can be done to test what type of infection you’ve got?
viral throat swab = can tell if got influenza A, influenza B or covid very quickly (within an hour) = these 3 are very infectious
what is good and bad about PCR?
good as multiplies numbers so test is very sensitive and specific
bad as can’t differentiate between alive & dead virus so result can remain positive if infection settled
- this is why history & symptoms are important as if clinical suspicion and positive test than high probability but if no clinical suspicion + positive test then low probability
what are some signs + symptoms of strep throat?
exudate, pus, sore throat, dysphagia, dysphonia
what are tonsillitis signs + symptoms?
swollen tonsils, erythematous, dysphagia, dysphonia
what scoring system can be used to try and help determine if antibiotics needed?
FeverPAIN
- Fever
- Purulence (pus)
- Attended rapidly (to hospital within 3 days of symptoms onset)
- Severely inflamed tonsils
- No cough or coryza
0 or 1 = 18% chance of isolating strep
2 or 3 = 40% chance of isolating strep
4 or 5 = 65% chance of isolating strep
what is quinsy?
a complication of tonsillitis, a peritonsillar abscess
= can be drained (used to be a lot) but has artery close by so have to be aware of internal carotid artery
what is epiglottitis?
infection of epiglottis = used to kill lots of babies + children = very frightening but luckily happens less now due to vaccine
what is management of epiglottitis?
- Historically this was most commonly associated with Haemophilus Influenza B
- Most cases are now caused by other bacteria - typically strep pneumonia/pyogenes, or staph aureus.
you should secure the airway with ET tube (you only get one go at this)
then, urgent administration of IV antibiotics – ceftriaxone, vancomycin, or clindamycin.
what is common cold- coryza infection of and how does it spread?
acute viral infection of nasal passages = Spread by droplets and fomites (fomites are lighter that stay in air, droplets heavy and drop into things)
what are complications of common cold?
- sinusitis
- acute bronchitis
what are common viruses causing common cold?
- Adenovirus
- Rhinovirus
- Respiratory Syncytial Virus = can be life threatening
- 30% Coronaviruses
what are symptoms of sinusitis?
- frontal headache
- retro-orbital pain
- maxillary sinus pain
- tooth ache
what helps sinusitis?
= it’s self limiting so mostly just gets better by itself in around 10 days but it can be soothed by washing out with salt water, nasal decongestant like oxymetazoline or Pseudo-ephedrine (decongestant medicine)
- sometimes antibiotics are needed
when is sinusitis dangerous?
fungal sinusitis is very bad - eats up to your brain
what is diphtheria?
= inflammation of mucous membranes
- Life threatening due to toxin production which causes sepsis
*not seen much in UK, used to not see at all due to vaccination but now seeing again due to absence of vaccination
what is a key characteristic of diphtheria?
pseudomembrane = characterized by the formation of a dense, gray debris layer composed of a mixture of dead cells, fibrin, RBCs, WBCs, and organisms
what is incubation time of rhinoviruses and group A streptococci?
1-5 days
what is incubation time of influenza + parainfluenza viruses?
1-4 days
what is incubation time of RSV + covid?
7 days
what is incubation time of diphtheria?
1-10 days
what is incubation time of epstein barrr virus?
4-6 weeks
what drug can be given in hospitals to shorten incubation times?
tamiflu = shortens by half a day which doesn’t sound like much but over big group, frees up beds
what is an example of lower respiratory tract infection?
- acute bronchitis
what is acute bronchitis?
swelling of bronchi- had a cold that went down to chest (often preceded by cold)
= not life-threatening
what are clinical features of acute bronchitis?
- productive cough
- fever - minority of cases
- normal chest examination
- normal chest x-ray
- may have transient wheeze (because of narrowing of airways)
what is tracheitis?
infection of trachea, very painful cough that burns in middle of chest
what is treatment of acute bronchitis?
- most people get better quickly themselves (self-limiting). can have paracetamol and plenty of fluids
- antibiotics not indicated
*can lead to specific morbidity in patients with chronic lung disease or immunosuppressed etc etc
what questions should be asked in COPD exacerbation to help determine whether infective exacerbation?
- Increased sputum production
- Increased sputum purulence
- More wheezy
- Breathlessness
on examination, what should be looked to for to help determine whether infective exacerbation of COPD?
- Respiratory Distress
- Wheeze
- Coarse crackles
- May be cyanosed
- In advanced disease – (worsening) ankle oedema
what is treatment for infective exacerbation of COPD?
- antibiotic = doxycycline or amoxicillin
- bronchodilator inhalers
- short course of steroids - prednisolone
what additional tests should be done if infective COPD exacerbation sent to hospital?
- Measure arterial blood gases
- CXR to look for other diseases
- Give oxygen if hypoxaemic – refer to the oxygen lectures.
- Rest initially, then mobilise – start pulmonary rehab early
what is red hepatisation of lung in pneumonia?
red hepatisation due to the resemblance to liver tissue rather than lung tissue because too much blood and fluid and not enough light air like it should be
what are some signs of pneumonia?
- Pyrexia = fever
- Rigors = chills
- Herpes labialis = cold sores from herpes simplex virus
- Tachypnoea = rapid or shallow breathing
- Crackles = heard in auscultation
- Rub = abnormal heart sound in auscultation
- Cyanosis
- Hypotension
what is anorexia in context of symptoms?
loss of appetite
what is myalgia?
muscle pain or discomfort
what is arthralgia?
joint pain or discomfort
what is pleurisy?
pleuritis, inflammation of pleura
what is rigors?
chills
why is herpes labialis a symptom of infection?
it’s a reactivation of herpes simplex virus - stress can bring back as lies dormant in nerve root ganglia and is controlled by immune system so when stress or illness immune system no longer in control and virus travels along nerve and cold sores erupt
what does sputum colour indicate?
indicates whether someone has acute bacterial infection - darker = worse
what does pink frothy sputum mean?
pulmonary edema
what are important tests for investigating pneumonia?
- Blood culture
- Serology
- Arterial gases
- Full blood count
- Urea
- Liver function
- Chest X-ray = timing important as early on normal xray
what is CURB 65 score?
= severity score for community acquired pneumonia (to predict mortality)
C New onset of confusion
U Urea >7
R Respiratory rate >30/min
B Blood pressure Systolic <90 OR Diastolic <61
65 age 65 years or older
Score 1 point for each of above
what are the meaning of the scores of the CURB 65?
30 Day mortality:
0 - 0.6%
1 - 2.7%
2 - 6.8%
3 - 14.0%
4 - 27.8%
5 - 27.8%
*if got COPD you add 10% onto mortality
why does sepsis kill people?
if not perfusing end organs = sepsis
sepsis - acidosis - enzyme failure - failure of oxidative phosphory;ation
what are some other severity markers (not in CURB 65 score) of penumonia?
- Temperature < 35 or > 40
- Cyanosis PaO2 < 8 kPa
- WBC < 4 or > 30
- Multi-lobar involvement
what is management of community acquired pneumonia?
- Antibiotics = Amoxicillin or Doxycycline
- Oxygen = Maintain SaO2 94-98 % or 88-92 %
- Fluids
- Bed rest
- No smoking
when should you send sputum? when does it matter?
= don’t send for everyone but do for recurrent, severe, persistent or previously known to have persistent organs
when is staph aureus more prevalent cause of pneumonia?
in hospital + ICU
when are gram negative bacteria more likely causes of pneumonia?
hospital acquired pathogens, but can be found in patients with chronic lung disease (pseudomonas, in particular).
what can mycoplasma pneumonia cause?
Wide range of pathologies
- Pneumonia
- Hepatitis
- Immune thrombocytopenic purpura
- Autoimmune haemolytic anaemia
- Arthritis
what happens to cells in mycoplasma pneumonia?
- Cillial Dysfunction
- H2O2 production damages respiratory membranes (and erythrocytes)
= causing protracted paroxysmal cough (persistent and recurrent cough that occurs in sudden, violent bursts or episodes, lasting for an extended period of time)
when are IV antibiotics needed?
- oral route not available (vomiting or person has nothing by mouth)
- sensitivities (drug resistant organs = pseudomonas resistant to 1 oral antibiotic ciprofloxacin)
- deep seated infections = abscesses, bone, endocarditis, meningitis. when difficult to get high levels into skin e.g. obese
- first dose = rapid increase in plasma concentrations
what is general antibiotic stewardship?
try to give oral rather than IV; narrow spectrum rather than broad; short courses (usually) just as effective as longer courses (There are special cases where longer courses are necessary, like Lyme disease)
what scenarios is it important to send sputum test?
- Resistant organism suspected
- TB or NTM suspected
- Failure to improve on standard therapies
- High risk individuals
what does brown rusty sputum mean?
cancer
