11. Nosocomial infection Flashcards
what % of hospitalised patient acquire infection whilst being there
5-10%
what % of hospital acquired infections (HAI) are bacterial and viral
95% bacterial
5% viral and parasites
what proportion of COVID-19 patients contracted the disease from hospital in the first wave
1/10
what is the most common HAI
surgical site infection
what % of HAIs does sepsis make up
3-5%
what are the 2 sources of infection
exogenous
endogenous
what is an exogenous source of infection
- direct inoculation of organism into patient without colonisation
what is an endogenous source of infection
- infections that are caused by already colonising microorganisms
describe and give an example of early endogenous infection
s. pneumoniae -> host already had this flora present prior to hospitalisation
describe and give an example of late endogenous infection
MRSA - hospital flora which first colonise the patients body and then cause infection
what surgical device is responsible for the highest cases and mortality of pateitns
respiratory therapy = respirators
define comorbidities
another disease that may compromise the treatment of another
give an example of a comoribidity
necrotising fasciitis and diabetes
explain necrotising fasciitis
necrotic flesh dies
symptoms: excessive pain, hard skin, swelling
bullae are formed and bleeding into the skin occurs
risk factors for necrotising fascitis include diabetes - impaired vascular and immune function
what type of necrotising fasciitis are most cases
type 1
caused by mix of gram neg and gram pos bacteria
describe necrotising fasciitis as a result of clostridial infection
produces 2 deadly toxins that cause platelet aggregation and RBC destruction
bacteria ferment in the wound and result in gas-gangrene
what do other types of necrotising fasciitis affect
extremities in young, healthy adults with history of injury
in burn units, what % of deaths are caused by infection
61%
why are burn victims predisposed to complications
burn wounds induce metabolic and inflammatory alterations
what pathogen become prominent following the invention of air conditioning systems
legionella
how can infections be transmitted in hospitals
poor hand hygeine lack of properly sterilised instruments air conditioning indirect contact environment/ food
study: Semmelweis
- mortality caused by post partum infection decreased from what to what following hand washing
decreased from 13.1%
to 2.4%
Why does having diabetes affect necrotising fasciitis
Diabetes = reduced blood flow to extremities
Harder to mobilise the immune system = reduced function
More difficult to combat other infections such as necrotising fasciitis
