Infection Control and Sterile Technique

Standard precautions are the baseline practices applied to all patients, regardless of their diagnosis or perceived risk. Treat all blood, body fluids, secretions, and excretions as if they contain bloodborne pathogens (HIV, HBV, HCV) or other infectious agents. Core precautions: (1) Hand hygiene: wash hands with soap and water after visible soiling, or use alcohol-based sanitizer for routine contact (before and after patient contact, before clean/aseptic procedures, after body fluid exposure). (2) Gloves: wear when touching blood, body fluids, mucous membranes, non-intact skin, or contaminated items; change after each patient. (3) Mask and eye protection: wear if splash of blood/body fluid is possible. (4) Gown: wear if clothing is likely to soil. (5) Safe injection practices: use a sterile needle for each injection, never reuse needles, dispose in sharps containers. (6) Respiratory etiquette: cover mouth and nose with tissue when coughing/sneezing, dispose of tissue, perform hand hygiene. These simple practices prevent the vast majority of healthcare-associated infections (HAIs) and protect staff and patients. Studies show compliance rates are often low (<50%), so vigilance and peer monitoring are essential.

Precautions are added layers for specific patients with known or suspected infections requiring isolation beyond standard precautions. Contact precautions: for infections spread by direct skin-to-skin contact or by contaminated surfaces (MRSA, C. difficile, norovirus, monkeypox). Use gloves and gown for patient contact, avoid touching environment, limit contact. Droplet precautions: for infections spread by respiratory droplets over short distances (influenza, measles, pertussis, scarlet fever). Use surgical mask and eye protection if within 3–6 feet of patient, keep patient's door closed, limit transport outside room. Airborne precautions: for infections spread by tiny airborne particles that float on air currents (tuberculosis, measles, varicella). Use N95 respirator (fitted mask), place patient in negative-pressure room (air flows in, not out), limit non-essential personnel, use appropriate PPE for all entries, restrict patient movement outside room. Some infections require combination precautions (contact + droplet, or droplet + airborne). The key is matching precautions to transmission route: contact precaution won't stop TB, droplet precaution won't stop C. difficile spores.

Hand hygiene is the single most effective way to prevent infection. Technique: wet hands with water, apply soap, rub vigorously for 20 seconds (count to 20, or sing 'Happy Birthday' twice), working between fingers, under nails, and wrists, then rinse with water. For waterless sanitizer: apply enough to wet hands, rub vigorously for 20 seconds, let air-dry (don't wipe with tissue). When to wash: (1) before eating, drinking, touching face, or using restroom; (2) after touching blood, body fluids, or non-intact skin; (3) after handling contaminated items; (4) before and after patient contact; (5) before clean or aseptic procedures; (6) after touching patient's surroundings. Compliance is low (~50%) in busy units, so regular audits and peer feedback improve rates. Gloves do NOT eliminate the need for hand hygiene — gloves contain small tears, and skin flora contaminate hands during removal. Some infections (C. difficile spores, norovirus) survive alcohol-based sanitizers, so soap and water is necessary; sanitizer is adequate for most other pathogens and is faster, so use it for routine contact when there's no visible soiling.

A sterile field is a workspace where all items are aseptic (free from disease-causing bacteria). Maintain sterility by: (1) Opening sterile packages on a clean, dry surface using aseptic technique (open tape flap away from your body, let contents drop gently onto the field or into your gloved hands, never reach across the field). (2) Keeping the field dry; moisture allows bacteria to migrate. (3) Keeping all items that touch the field sterile (sterile gloves, sterile instruments, sterile gauze, sterile solutions). (4) Never touching the field with non-sterile hands or items. What breaks sterility: (1) Touching the sterile field with non-sterile hands or gloves; (2) A non-sterile item (your pen, your watch, a non-sterile instrument) touching the field; (3) Moisture from the environment dripping onto the field; (4) Reaching across the field with non-sterile arms; (5) Turning your back to the field (you cannot see it, and someone or something might contaminate it); (6) Talking over the field (respiratory droplets contaminate it). If the field is broken, discard all items and start fresh with new sterile supplies. If you're unsure whether something is sterile, treat it as non-sterile.

High-risk procedures: any involving needles, lancets, or sharp instruments that pierce skin and may contact blood. Examples: venipuncture (phlebotomy), IV insertion, injections, finger-stick glucose testing, surgical procedures, and dental work. Prevention: (1) Never recap needles by hand (the leading cause of needlestick injury). After use, immediately place the needle in a sharps container at point of use. (2) Use safety-engineered devices (retractable needles, blunt cannulas, self-capping syringes) when available. (3) Do not pass sharps from hand to hand; place them on a sterile surface for the other person to pick up. (4) Keep sharps containers within arm's reach so you don't carry sharps across the unit. (5) Fill sharps containers only 2/3 full so they don't overflow and cause spills. (6) Never put sharps in regular trash. (7) If you have a needlestick, immediately wash with soap and water, report to occupational health, identify the source patient if possible, and test for bloodborne pathogens (baseline, then follow-up testing at 6 weeks, 3 months, 6 months for HIV/HBV/HCV). Post-exposure prophylaxis (PEP) for HIV must start within hours; HBV vaccine may be indicated.

MDROs are bacteria resistant to multiple antibiotics, making infections harder or impossible to treat. Common hospital MDROs: MRSA (methicillin-resistant Staphylococcus aureus), VRE (vancomycin-resistant enterococcus), ESBL-producing gram-negatives, C. difficile, and carbapenem-resistant organisms (CROs). These organisms are spread by contact with colonized or infected patients or contaminated surfaces. Prevention: (1) Hand hygiene (especially important for C. difficile, which is not killed by alcohol-based sanitizers; use soap and water). (2) Contact precautions: gloves and gown for all patient contact, avoid touching environment, clean equipment after use. (3) Dedicated equipment: if possible, use dedicated blood pressure cuffs, stethoscopes, and other equipment for MDRO patients so you don't contaminate other patients' equipment. (4) Environmental cleaning: use EPA-registered disinfectants approved for the specific organism (C. difficile requires bleach solutions or sporicidal agents). (5) Screening: some hospitals screen high-risk patients (intensive care, long-term care, recent hospitalization) and implement precautions preemptively. (6) Antibiotic stewardship: use antibiotics only when indicated and for the shortest effective duration to reduce selective pressure that enables MDRO emergence.

Donning (putting on) sequence: (1) Hand hygiene first. (2) Gown: tie at back, cover the back of your body. (3) Mask or N95: secure around nose and mouth (fit-test for N95 annually and perform seal check before use — exhale, feel for air leaks; if you feel air at edges, readjust). (4) Goggles or face shield: secure over eyes and face. (5) Gloves: don sterile gloves if an aseptic procedure, or non-sterile if isolation care (pull gloves over gown cuffs so they cover the gown). Doffing (removal) sequence (reverse order to avoid contaminating yourself): (1) Gloves: pinch the outside of one glove near the wrist, peel it off inside-out, hold the removed glove in your gloved hand, then peel the second glove inside-out over the first, and discard in biohazard bag. (2) Goggles/face shield: handle by the strap, not the face-contact surface. (3) Gown: unfasten ties, peel away from shoulders, turn it inside-out and fold inward, discard in biohazard bag. (4) Mask/N95: pinch the tie or elastic, do not touch the face-contact surface. (5) Hand hygiene immediately after. If you touch your face, a non-sterile surface, or contaminated equipment during doffing, start over with clean PPE. Doffing is where many contaminations occur, so go slowly and think through each step.