1. Prevention, Screening, Immunization
Forewarned is forearmed

2. Prevention
 Primary- avoids development of disease
 Secondary- early disease detection to
prevent emergence of symptoms &
progression of disease
 Tertiary- reduces impact of an
established disease by restoring
function & reducing complications

3. Tiers of preventive intervention
 Universal- addresses entire population
 Selective- focuses on groups at higher
risk of developing problem based on
age, gender, F/H, economic status
 Indicated- screening to identify
individuals with early symptoms/signs

4. Leading causes of death
 Hypertension
 Smoking
 High cholesterol
 Malnutrition
 STD
 Overweight & obesity
 Physical inactivity
 Alcohol
 Pollution
 Unsafe water & poor sanitation

5. Good habits
 Adequate physical activity
 Moderate intensity aerobic exercise x >30 mins./day, 5 d./wk.
 Vigorous intensity aerobic exercise x >20 mins./day, 3 d./wk.
 Diet
 Emphasize whole grain, fruits, vegetables, low-fat dairy
 Limit saturated fat, cholesterol, sugar, salt
 Maintain weight
 BMI- 18.5-24.9 Kg./metre square
 Waist circumference- M<35 inches/90 cm., F<32 inches/80cm.
 Avoid harmful drinking (alcohol)
 M>14/wk. & >4 per occasion; F>7/wk. & >3 per occasion
 Abstinence from tobacco or tobacco smoke
You increase your age by at least 10 years
3

6. Screening
 Strategy used in a population to detect a
disease in individuals without symptoms or
signs of that disease
 Leads to early diagnosis for intervention
 Test used must have high sensitivity and
specificity; to avoid underdiagnosis,
overdiagnosis, false sense of security or
undue panic
 Has associated cost

7. Biases
 Lead time bias, no survival benefit
 Length time bias in detecting slow growing
cancers that do not change survival
 Selection bias- who is screened
 Overdiagnosis bias- picking harmless
diseases
 Avoiding bias- no randomized controlled trial
for want of time and money

8. Principles of screening- WHO
 Important health problem
 Treatable
 Availability of facilities
 Latent stage of disease
 Available & acceptable test
 Cost to individual & society
 A continuous process

9. USPSTF recommendations
 Hypertension- all adults >18 q 1-2 yrs.
 Cholesterol- M>35, F>45 q 5 yrs.
 Diabetes- all hypertensives
 Osteoporosis- F>65
 Breast cancer- 50-74, M’graphy q 2 yrs.
 Cervix cancer- Pap smear in sexually active
women; q year x 3  q 3 years
 Colon cancer- 50-75, FOBT/S’scopy/C’scopy

10. USPSTF contd.
 Harmful drinking- ask & counsel
 Tobacco use- ask & intervene
 Diet & physical activity- counsel
 Hepatitis B- screen in pregnancy
 HIV- screen those at risk
 Folic acid & Iron supplements in pregnancy

11. Screening- no benefit
 CAD
 CVA/Stroke
 DM
 COPD
 (routine) Lab testing
 CA-125 & US for Ca. Ovary
 Lung cancer

12. Vaccination
 Administration of vaccine (foreign
antigenic material) to produce immunity
 Specific and rapid immune response
 Most effective and cost-effective
method of preventing infectious disease
 Edward Jenner- 1796- Cowpox vaccine
 Smallpox eradicated-1977

13. Vaccination- types
 Heat/formaldehyde inactivated virus,
booster shots required to reinforce
 Live attenuated (low virulence) virus,
can’t be used in immunocompromised
 Virus-like particle derived from
structural proteins of a virus
 Subunit vaccine (bacteria/virus),
elicits weakest immune response

14. Vaccination- children
 BCG
 OPV/IPV
 DTP/DTaP
 Rotavirus
 Hib
 Hep. B
 MMR
 Varicella- Chickenpox
 Influenza, Meningo. & Pneumococcal, Hep. A

15. Vaccination- adult
 Td booster- q 10 years
 HPV- 3 doses before 26 years
 Varicella- 2 doses
 MMR- 1 or 2 doses
 Influenza- annually
 Pneumococcal- 1 dose
 Hepatitis B- 3 doses (no booster reqd.)

16. Preoperative evaluation
 Medical history
 Indication for Sx
 Drug allergies/intolerances
 Known medical problems & their current status
 Current medications
 Cardiac/Pulmonary/Functional status
 Possibility of symptomatic anemia or pregnancy
 h/o surgery & anesthesia
 Physical exam
 Wt., Ht., Vitals, Cardio-pulmonary, other pertinent exam

17. Preoperative investigation
 Hb- h/o anemia/recent blood loss
 Potassium- on digoxin/diuretics/ACEI/ARB
 Coag. studies- known hist., on anticoag.,
need for postop. anticoagulants
 CxR- s/s of new/unstable cardiopulm. disease
 ECG- s/s of new/unstable cardiac disease, no
ECG within last 1 yr. in pts. of DM/HT/CHF,
chest pain/smoking/PVD/morbid obesity

18. Preoperative antibiotics
 Single dose preoperative antibiotic- assuming
an uncomplicated procedure
 Administered within 1 hour of incision
 Readministered every 3 hours during
prolonged procedure
 Antibiotic to target anticipated organism-
Cefazolin suffices in majority
 Additional coverage in complicated,
contaminated, dirty procedures