hospital acquired infections

1. Nosocomial infections or
Hospital acquired infections
Welcome to the
hospital!
Bugs are waiting
for you!!!

2. • Any clinical infection that was neither
present nor was in its incubation period
when the patient is admitted in a hospital.
• The term "nosocomial" comes from two
Greek words: "nosus" meaning "disease" +
"komeion" meaning "to take care of." It is
now synonymous with hospital-acquired.

3. • Nosocomial infections may also make their
appearance after discharge from the hospital,
if the patient was in the incubation period at
the time of discharge.
• If someone in a hospital slips and breaks their
hip, could that be a nosocomial fracture of
the femur? No way. The only things that are
nosocomial these days are infections.

4. • One of the earliest records of hospital
infections are found the famous writings of
physician Charaka and surgeon Sushuruta
(400 B.C.) who
have emphasized the
need for prevention
of infection in
clinical practice.

5. WHY ARE NOSOCOMIAL INFECTIONS
COMMON?
• Patients with infections or carriers of pathogenic
microorganisms are admitted
• Hospitals house large numbers of people whose
immune systems are often in a weakened state.
• Medical staff move from patient to patient,
providing a way for pathogens to spread.
• Many medical procedures bypass the body's natural
protective barriers.
• Increased incidence of antibiotic resistance.
• Decreased bed spacing

6. Epidemiology & Burden
• Nosocomial infections occur in about 5-10
percent of hospital admissions, worldwide.
In India, the nosocomial infection rate is
alarming and is estimated at about 30-35
percent of all hospital admissions.
• According to WHO average of 8.7% of
hospital patients have nosocomial
infections.
• At any time, over 1.4 million people
worldwide suffer from NCI

7. NOSOCOMIAL INFECTIONS IN INDIA
• Frequency is 1 in every 4 patients admitted
into the Hospital.
• 1/3rd of all such infections are preventable.
• Responsible for more mortality than any
other form of accidental death.

8. NOSOCOMIAL INFECTIONS IN
DEVELOPED NATIONS
• In U.S. around 1.7 million HAI’s occur each year
and 99,000 people lose their lives.
• In Europe around 25,000 deaths occur each year.
• Overall there are about 2 million annual cases of
HAI’s in developed nations.
• Frequency of HAI’s in developed nations is 5-
10%.
• It accounts for annual cost of $4.5 - $11 billions
in U.S.

9. • Rates vary between countries, within the
country, within the districts and sometimes
even within the hospital itself, due to
1) complex mix of the patients
2) aggressive treatment
3) local practices

10. CONSEQUENCES OF NOSOCOMIAL
INFECTIONS
1. Prolongation of hospital stay:
Varies by site, greatest with pneumonias and
wound infections
2. Additional morbidity
3. Mortality increases - in order - LRI, BSI, UTI
4. Long-term physical &neurological consequences
5. Direct patient costs increased-
Escalation of the cost of care

13. TYPES BY ORIGIN
1.Patients own flora - Endogenous (50%)
Auto-Infection
( Greatest source of potential danger)
2.Environment - Exogenous(50%)
(Air-5%; Instruments-10%)
Another Patient/Staff - Cross Infection (35%)

14. Pathological agents – important
nosocomial pathogens
• Bacteria (most common nosocomial
pathogens):
Commensal bacteria - Staphylococcus
epidermidis, Escherichia coli
Pathogenic bacteria - Staphylococus aureus,
M.R.S.A, Streptococcus, Clostridium, . E. coli,
Proteus, Klebsiella, Enterobacter,
Pseudomonas , Legionella , VRE

15. • Viruses: hepatitis B and C viruses ,RSV, rotavirus, and
enteroviruses .Other viruses such as C.M.V, HIV, Ebola,
influenza viruses, herpes simplex virus, and varicella-
zoster virus
• Parasites and Fungi:
Many of tham are opportunistic organisms and cause
infections during extended antibiotic treatment and severe
immunosuppression (Candida albigans, Aspergillus spp.,
Cryptococcus neoformans, Cryptosporidium, Pneumocystis
carini, Toxoplasma pneumoniae).
Sarcoptes scabies (scabies) is an ectoparasite – outbreaks
In health care facilities.

16. MECHANISMS OF TRANSMISSION
1) Contact: direct (person-person), indirect (transmission
through an intermediate object-- contaminated instruments
---Cross transmission
2) Airborne: organisms that have a true airborne phase as
pattern of dissemination (TB, Varicella)
3) Common-vehicle: common animate vehicle as agent of
transmission (ingested food or water, blood products, IV
fluids)
4) Droplet: brief passage through the air when the source and
patient are in close proximity
5) Arthropod

17. ICUs Are Dangerous Places!!!
• The sickest patients are placed in proximity
• AB are given empirically in large doses
• Devices are everywhere (often pts have 3, 4 or
more)
• Frequent use of invasive devices
• Staff busy caring for very ill pts
• Staff move from one pt to other without
washing hands
• Longer ICU stay prolonging the risk of exposure
• Space limitations

18. RISK FACTORS
• Extremes of age
• Sex (females with UTI)
• Malnutrition
• Use of antibiotics
• Diabetes, and causes of immunosuppression
• Altered mental status
• Surgery
• ICU setting, endotracheal intubation with
mechanical ventilation

19. Sites of NCI with their incidence
• Average Incidence - 5% to 10%, but maybe up
to 28% in ICU
1) Urinary Tract Infection - usually catheter
related -28%
2) Surgical Site Infection or wound infection -
19%
3) Pneumonia -17%
4) Blood Stream infection - 7% to 16%
5) Others – GIT, CNS- 10 to 20%

22. AGE RANKS OF NCIs
Ranks in
infants
1) SKIN
2) LRI
3) BSI
4) UTI
5) SWI
Ranks in
children
1) SKIN
2) LRI
3) BSI
4) UTI
5) SWI
Ranks in
adults
1) UTI
2) LRI
3) SWI
4) BSI

23. Nosocomial Urinary Tract Infections

24. URINARY TRACT INFECTIONS
• Most common site of NI
• Affects (5%) of admissions
• 80% related to urinary catheters
• Associated with 2/3 of cases of
nosocomial gram negative
bacteremias.

25. PATHOGENESIS
• Major risk factors:
• 1) pathogenic bacteria in
periurethral area
• 2) indwelling urinary catheter
– Duration catheterization
• Bacterial factors:
– properties which favor
attachment to uroepithelium,
catheters
• Bladder trauma decreases local
host defenses
Urinary (Foley) Catheter

26. TREATMENT
• Is this a UTI vs asymptomatic bacteruria?
– Use clinical judgement
- urine WBC- pyuria
- bacterial colony counts > 103
- clinical signs/symptoms
• No antibiotic treatment for bacteruria
- resolves with catheter removal
• Empiric therapy typically initiated pending microbiologic
results

27. Surgical Site Infections

28. SURGICAL SITE INFECTIONS
• (2nd most common)
• Incisional infections
– Infection at surgical site
– Within 30 days of surgery
– Involves skin, subcutaneous tissue, or muscle above
fascia
– Accompanied by:
• Purulent drainage
• Dehiscence of wound
• Organism isolated from drainage
• Fever, erythema and tenderness at the surgical site

29. SSI: Superficial

30. SURGICAL SITE INFECTIONS
• Deep surgical wound infection
– Occurs beneath incision where operation took place
– Within 30 days after surgery if no implant, 1 year if
implant
– Infection appears to be related to surgery
– Occurs at or beneath fascia with:
• Purulent drainage
• Wound dehiscence
• Abscess or evidence of infection by direct exam
• Clinical diagnosis

31. SSI: Deep

32. SURGICAL SITE INFECTIONS
• Risk of infection dependent
upon:
–Contamination level of wound
–Length of time tissues are
exposed
–Host resistance

33. PATHOGENS ASSOCIATED WITH SWI
Pathogen % of Isolates
S. aureus 17
Enterococci 13
Coag - Staph 12
E. coli 10
P. aeruginosa 8
Enterobacter 8
P. mirabilis 4
K. pneumoniae 3
Streptococci 3

34. Treatment
• Surgical-site infections (SSIs) should be managed
with a combination of surgical care and
antibiotic therapy. Antibiotic coverage should be
modified once culture results are available.
• Severe infections such as streptococcal gangrene
and extensive tissue necrosis need aggressive
surgical intervention. For these kinds of
infections, antibiotics alone may not work.

35. Nosocomial Pneumonia

36. NOSOCOMIAL PNEUMONIA
• Lower respiratory tract infection
• Develops during hospitalization
• Not present or incubating at time of
admission
• Does not become manifest in the
first 48-72 hours of admission

37. EPIDEMIOLOGY
• 13-18% of nosocomial infections
• 6-10 episodes/1000 hospitalizations
• Leading cause of death from NI
• Economic consequences
–prolongation of hospital stay 8-9
days

38. Nosocomial Pneumonia
• Cumulative incidence = 1-3% per day of intubation
• Early onset (first 3-4 days of mechanical ventilation)
– Antibiotic sensitive, community organisms
(S. pneumoniae, H. influenzae, S. aureus)
• Late onset
– Antibiotic resistant, nosocomial organisms (MRSA, Ps.
aeruginosa, Acinetobacter spp, Enterobacter spp)

39. Multiresistant bacteria are a problem
in VAP
7.7S. pneumoniae
% of all isolatesOrganism
3.1MSSA
8.4H. influenzae
11.8A. baumannii
11.8MRSA
31.7P. aeruginosa
Rello J. Am J Respir Crit Care Med 1999; 160:608-613.
(n = 321 isolates from 290 episodes)

40. DIAGNOSIS AND TREATMENT
• Clinical diagnosis
- fever, change in O2, change in sputum, CXR
• Microbiologic Confirmation
– Suctioned Sputum sample
– Bronchoscopy with brochoalveolar lavage
• Empiric antibiotic-
Rx based on previous cultures, usual
hospital flora and susceptibilities

41. Nosocomial Bloodstream Infections

42. NOSOCOMIAL BACTEREMIA
• 4th most frequent site of NI
• Attributable mortality 20%
• Primary
* IV access devices
* gram positives (S. aureus, CNS)
• Secondary
* dissemination from a distant site
* gram negatives

43. The CVC- is one of the most
commonly used catheters in
medicine
The CVC is typically placed
through a central vein such as
the IJ, Subclavian or femoral
The major risk factor is the Central Venous Catheter
(CVC)
These serve as
direct line for
microbial
bloodstream
invasion

44. PATHOGENESIS
• Direct innoculation
* during catheter insertion
• Retrograde migration
* skin→subcutaneous tunnel→fibrin sheath
at vein
• Contamination
* hub-catheter junction
* infusate

45. Nosocomial Bloodstream Infections
Rank Pathogen Percent
1 Coagulase-negative Staph 31.3%
2 S. aureus 20.2%
3 Enterococci 9.4%
4 Candida spp 9.0%
5 E. coli 5.6%
6 Klebsiella spp 4.8%
7 Pseudomonas aeruginosa 4.3%
8 Enterobacter spp 3.9%
9 Serratia spp 1.7%
10 Acinetobacter spp 1.3%

46. Treatment
• Antibiotics with coverage against gram-positive and
gram-negative organisms, including Pseudomonas,
should be empirically started and then tailored
according to susceptibility pattern of isolated
organisms.
• Antifungal therapy (eg, fluconazole, caspofungin,
voriconazole, amphotericin B)
• Antiviral therapy (eg, ganciclovir, acyclovir) can be
used in the treatment of suspected disseminated viral
infections.
• For most bacterial organisms, the duration of therapy
is 10-14 days after blood cultures become negative.

47. Prevention

48. Hand hygiene is the
single most important
measure for control
of nosocomial
infections

49. Why it is the single most important
measure??
Healthcare workers can get 100s to 1000s of
bacteria on their hands by doing simple tasks like:
• pulling patients up in bed
• taking a blood pressure or pulse
• touching a patient’s hand
• rolling patients over in bed
• touching the patient’s gown or bed sheets
• touching equipment like bedside rails, overbed
tables, IV pumps

50. Hand Hygiene Techniques
1. Alcohol hand rub
2. Routine hand wash 10-15 seconds
3. Aseptic procedures 1 minute
4. Surgical wash 3-5 minutes

52. Preventive measures:
• Proper means of disinfection and sterilisation (physical,
chemical and biological tests)
• Disposable instruments (cost/effectiveness!),
• Separation or/and exclusion of suspect sources (patients,
visitors),
• Strict rules in handling the bedclothes, meals and hospital
wastes,
• Proper means of disinfection of patient equipment

53. • Judicious use of Antimicrobial agents to prevent
MDR
• Place patients with a confirmed MDRO or
history of an MDRO in single-patient rooms.
• Gown and gloves worn upon entering room
• Use eye/face protection if risk of splatter/splash
is anticipated (e.g., patient is coughing or
sneezing or has trach)
• Avoid catheter when possible & discontinue
ASAP
• PROPHYLACTIC PREOPERATIVE ANTIBIOTICS

54. For pneumonia - Pulmonary toilet
• Change position q 2 hours
• Elevate head to 30-45 degrees
• Deep breathing, incentive spirometry
• Frequent suctioning
• Bronchoscopy to remove mucous plugging
For BSI
• Line removal should be considered if the line
is no longer needed

55. Environmental Measures
• Clean and disinfect high-touch surfaces :
(e.g. bedrails, faucet handles) and
equipment used in the patient’s
environment that may be contaminated
with pathogens
• Adequate ventilation systems
• Proper disposable of wastes

56. Hospital management measures
• Hospital management should establish a
multidisciplinary Infection Control Committee
• Identifying appropriate resources for a programme to
monitor infections and apply the most appropriate
methods for preventing infection
• Ensuring education and training of all staff through
support of programmes on the prevention of
infection in disinfection and sterilization techniques
• Bed spacing in general wards - 2.7m
• Bed spacing in ICU - 3.6 m

57. • The director of food services ensuring
appropriate handling and disposal of wastes
• The housekeeping service should maintain
high level of hygiene in the hospital
• Limiting the risk of endogenous infections by
minimizing invasive procedures.
• Periodically reviewing the status of
nosocomial infections and effectiveness of
interventions to contain them
• Making sure that all medical personnel are
immunised with hepatitis B vaccine.

58. Hospital-Acquired Infection Control
Committee(HAICC)
• Committee responsible for investigation hospital
acquired infection.
• Committee should be chaired by medical
superintendent, microbiologist as a control
officer, and heads of all department, blood
bank, microbiologist, medical record officer,
chief of nursing services and infection control
board as its members.
• Chief of all supporting services should be
included as invited members.

60. I may not have gone where I
intended to go, but I think I have
ended up
where I needed to be
Douglas Adams

61. The ultimate goal: patient safety