Skin Deep

Burns

100

List 4 general causes of burns

1. Thermal 2. Chemical 3. Radiation 4. Electrical

200

ANZBA criteria for referral (4)

Burns greater than 10% Total Body Surface Area (TBSA) Burns of Special Areas - Face, Hands, Feet, Genitalia, Perineum and Major Joints Full Thickness burns greater than 5% TBSA Electrical burns Chemical burns Burns with an associated inhalation injury Circumferential burns of the limbs or chest Burns at the extremes of age - children and the elderly. Burn injury in patients with pre-existing medical disorders which could complicate management, prolong recovery or affect mortality Any burn patient with associated trauma

300

How are burns classified? Explain.

1st degree - epidermis 2nd degree: superficial partial thickness - extends into superficial (papillary) dermis 2nd degree: deep partial thickness - extends into deep (reticular) dermis 3rd degree: full thickness - extends into entire dermis 4th degree: extends through entire skin, and into underlying fat, muscle and bone

400

A patient (M, 38 yo) came in with severe burns throughout his right leg. This is his vitals: BP 100/70, RR 20/min, HR 140/min reg, Temp 35.9°C, SaO2: 94% 6L via mask, Wt 80kg. Work out how much IV fluid should be given to this patient in the first 8 hour.

2880 mL

Systemic infections, SIRS, sepsis and septic shock

100

Gram-positive bacteria is more a common cause than gram-negative bacteria T/F?

T

200

What does a septic screen commonly involve?

Urinalysis – to rule out UTI, abdominal CT scan, CXR – to rule out pneumonia, FBC, CRP (raised in inflammation and infection), blood cultures

300

The principle of early management for septic shock involves fluid resuscitation. If the patient remains hypotensive, what should you do next?

Vasopressors – Indications: • Hypotension not responsive to fluid • Life threatening hypotension – Agents: • Noradrenaline • Adrenaline • Dobutamine –> tissue hypoperfusion despite adequate fluid resuscitation and blood pressure

400

What is SIRS and what are the criteria for SIRS?

Systemic Inflammatory Response Syndrome. Criteria - two or more of the following: - Temp >38C or <36C - HR >90 - RR >20 - PaCO2 <4.3 kPa - WBC >12000 cells/mm3 or <4000 cells/mm3 or >10% immature (band) forms

Antimicrobial therapy

100

Which class of antibiotic is mostly associated with nephrotoxicity and ototoxicity? Example?

Aminoglycosides e.g. Gentamicin

200

mrsa infection is commonly treated with vancomycin. What is the mechanism of action of vancomycin?

Inhibits cell wall synthesis by binding to peptide chain rather than the PBP. This binding of vancomycin to the D-Ala-D-Ala prevents cell wall synthesis in two ways. It prevents the synthesis of the long polymers of N-acetylmuramic acid (NAM) and N-acetylglucosamine (NAG) that form the backbone strands of the bacterial cell wall, and it prevents the backbone polymers that do manage to form from cross-linking with each other.

300

What are the 3 major mechanisms of antimicrobial resistance?

– Destruction or inactivation of the drug • eg Beta-Lactamases – Prevention of penetration of drug to target site • Efflux pumps; tetracycline resistance • Alterations in porin characteristics – Alteration of antimicrobial target site • eg alterations in Penicillin Binding Proteins

400

List three classes of antibiotics that targets bacterial protein synthesis. What does each target?

1. Aminoglycosides - 30s subunit of ribosome 2. Tetracyclines - 30s subunit of ribosome 3. Macrolides - 50s subunit of ribosome

Health-care associated infections; post-operative fever

100

What are the most common causes of post-op fever?

Urine (UTI), Surgical site infection, Pneumonia, IV cannula-associated infection, DVT/PE

200

What are the common pathogens in hospital acquired pneumonia?

Enteric gram –ve bacilli (E coli, klebsiella) Pseudomonas aeroginosa Staph Aureus

300

Classification of Surgical Wounds (3)

1. Clean – No inflammation encountered; respiratory, alimentary and genitourinary tract not entered – e.g. mastectomy, hip replacement 2. Clean-contaminated – GI, GU or resp. tracts entered without significant spillage – e.g. laryngectomy, uncomplicated appendicectomy 3. Contaminated – Gross spillage from GI tract; entrance into GU or biliary tract in the presence of infected urine or bile. Traumatic wounds, or any wound in which pus is encountered – e.g. large bowel resection

400

List 4 common multi resistant organisms. In what condition does each infection normally occur?

1. nmMRSA - boils, severe sepsis, community acquired pneumonia 2. mMRSA - surgical site infections, IV lines, ventilator associated pneumonia 3. VRE - UTI, BSI from IV lines in chemo patients, liver abscess and BSI in liver transplant 4. ESBL (extended spectrum beta lactamase) E. coli - UTI/urosepsis, Biliary sepsis, Neutropenic sepsis