ID Flashcards
What are the positive acute phase reactants
CRP, ferritin, fibrinogen, hepcinin, amyloid A
What are the negative acute phase reactants
Albumin, transferrin, antithrombin
What is iron with holding - when would you see it
Acute infection
Drop in transferrin (prevent bacteria getting iron - they can scavenge from transferrin and macrophages)
Rise in ferritin because of fall in transferrin
Rise in hepcidin - causes reduced uptake of iron from gut and release of iron from cells (hepcidin regulates ferroportin)
Over long time this mechanism causes anaemia bc iron isnt absorbed, moved out of cells or transported
What needs to be checked when starting a pt on a macrolide
LFTs and stop statin
macrolides are P450 inhibitors
What is CURB 65
Confusion Urea >7 Respiratory rate >30 BP <90 / 60 >65
What is the management of CAP based on curb65 score
0-1 consider home management
2 consider admission / closer home monitoring
3 admit
What is the antibiotic management based on curb 65
0-2 PO amox plus/ or clarithyromycin ; 2nd line PO doxcy or levofloxacin
3-5 IV amox plus/ or IV clarithyromycin
If legionella pneumophila
1st line: PO/IV Levofloxacin or Clarithromycin
Complications of pneumonia
ARDS Pneumothorax Emphyema Pleural effusion PE Lung abscess Sepsis
Common and atypical pathogens for CAP
Strep pneumoniae
atypical - mycoplasma pneumoniae, legionella, chlamydia pneumoniae
Criteria for hospital acquired pneumonia
> 48 hours after hospital admission
pseduomonas more likely organism
klebsiella
bacteroides
Investigations for pneumonia
Sputum culture and PCR
Urinalysis for legionella antigens
What is the criteria for ARDS
CXR - bilateral infiltrates (normal heart size)
Acute onset (1 week)
Refractory hypoxaemia
Pulmonary wedge pressure <19 mmHg
What are red flags for ARDS
Diffuse fine crackles, non cardiogenic pulmonary oedema (on XR)
What is the main differential for ARDS
Cardiogenic pulmonary oedema (HF)
Features of HF on an XRay
A - alveolar odema B - Kerley B lines C - cardiomegaly D - dilated prominent upper lobe veins E - pleural effusions
What is an important consideration when considering whether NIV is appropriate for a pts
Secretions
Consciousness
Severe hypoxaemia
What are absolute contraindications to NIV
Facial burns/ trauma
Vomiting
Fixed obstruction upper airway
Recent facial upper airway surgery
what are the different levels of oxygen therapy and indications
Nasal cannula - 24-50% o2
Simple mask - 24-60% o2
Venturi mask - 24 - 60% o2 - COPD when need to know specificially what FiO2 being delivered
Non-rebreather + bag - 60-80% O2
What considerations should you think of before starting oxygen therapy
Acutely unwell - non rebreather + bag to get highest oxygen delivered
Risk of type 2 respiratory failure (COPD) - venturi lowest 28% - 4 L O2 until ABG results
What are the indications for noninvasive ventilation
Type 1 or 2 RF
If a patient has a NEWS of >3 what should you do
Sepsis screening tool ASAP
What size is petechiae
<3mm
What is the first step of management in suspected meningitis
IV ceftriaxone
Other investigations shouldnt delay giving antibiotics
What is the management of suspected meningitis
IV Ceftriaxone 2-4g daily, dose at the higher end of the recommended range used in severe cases.
Abx should be given within 1 hour
Symptoms of meningitis
Headache
Photophobia
Neck stiffness
N/ V
What type of antibiotics if ceftriaxone
Cephalosporin
What is the overlap of penicillin and cephalosporin allergies
Both beta lactams
0.5-6.5% of patients with penicillin allergy will also be allergic to other Beta-Lactams such as cephalosporins.
For this reason, patients with only a mild penicillin allergy (not anaphylaxis) should be given cephalosporins and be monitored closely for any drug reactions.
For patients with anaphylaxis to penicillin suspected of having acute bacterial meningitis, empirical guidelines state they should be given chloramphenicol 25mg/kg 6 hourly.
When should you do a lumbar puncture in suspected meningitis
Patient not in shock
In patients with suspected meningitis (with no signs of shock or severe sepsis) LP should ideally be performed within 1hr of admission to hospital. Treatment should be commenced immediatly after the LP. If delays to LP are anticipated this should not delay treatment which should be given straight after blood cultures and within the hour.
In patients who are unstable with rapidly evolving sepsis &/or rash, LP should not be performed at this time. Treatment should be given immediatly.
What bloods would you request for an unstable patient with suspected meningitis
full blood count, C-reactive protein, coagulation screen, blood cultures, meningococcal PCR and blood glucose
How do you determine if it is safe to do an LP
CT head if: - Focal neurological signs - Presence of papilloedema - Continuous or uncontrolled seizures - GCS <12 Lumbar puncture should not be performed in those with an uncorrected coagulopathy or those with evidence of skin infection near the site of the lumbar puncture.
What are the commonest causes of meningitis in adults
Streptococcus pneumoniae
Neisseria meningitidis
What should you consider in patients over 65 with suspected meningitis
Listeria
Include amoxicillin in treatment