How to Set Up a Sterile Field: Nursing Skills & Sterile Technique

Infection control refers to systematic measures to prevent and control infection spread in healthcare settings. Infection is defined as entry and multiplication of microorganisms (bacteria, viruses, fungi) in the body, which can be acute or chronic, symptomatic or asymptomatic. Modes of transmission include contact, droplet, airborne, vector-borne, and food/water-borne. The chain of infection consists of: Encounter (contact), Colonization (entry and multiplication), Penetration (tissue invasion), Spread (dissemination), and Resolution (immune response). Breaking any link prevents infection. Types include local, systemic, primary, secondary, acute, chronic, nosocomial, cross-infection, opportunistic, and subclinical. Risk factors include age, poor nutrition, low immunity, chronic diseases, stress, poor hygiene, skin breaks, invasive procedures, environmental factors, lack of immunization, smoking, and socioeconomic status.

The chain of infection consists of six interconnected components that explain how diseases spread. Infectious agents are microorganisms like bacteria and viruses that cause disease. The reservoir is where pathogens live and multiply, such as contaminated water, food, or surfaces. The portal of exit is how pathogens leave the reservoir, like through contaminated water or food. Mode of transmission describes how pathogens travel between locations, including direct contact or indirect contact through contaminated mediums. The portal of entry is how pathogens enter a host's body, such as through ingestion or skin contact. Finally, host susceptibility determines whether infection occurs, depending on the individual's immune system strength. Infection control aims to break this chain at any point to prevent disease transmission.

Infection control is the systematic prevention of disease transmission in healthcare settings through understanding the chain of infection (agent, reservoir, portal of exit, mode of transmission, portal of entry, and susceptible host) and implementing appropriate interventions at each link. The chain of infection includes: the infectious agent (bacteria, viruses, fungi, or parasites), the reservoir (source of the pathogen), the portal of exit (how the pathogen leaves the reservoir), the mode of transmission (how the pathogen travels), the portal of entry (how the pathogen enters a new host), and the susceptible host. Breaking any link in this chain prevents infection transmission. Key infection control methods include cleaning (removing visible dirt), disinfection (using chemical agents like phenol or iodine), and sterilization (complete elimination of all microorganisms using methods like autoclaving at 121-123°C for 29 minutes, ethylene oxide gas, or radiation). Medical asepsis (standard precautions) applies outside operating rooms, while surgical asepsis (sterile technique) is used during surgical procedures.

The chain of infection consists of five infectious agents (fungi, bacteria, viruses, protozoa, and rickettsia), reservoir hosts, portal of exit, mode of transmission (direct or indirect contact), portal of entry, and susceptible host; infection control requires breaking this chain through standard precautions including hand-washing, sanitization (reducing pathogens to safe level), disinfection (destroying pathogens), and sterilization (complete destruction of all microorganisms), with healthcare workers required to follow CLIA 1988 standards for proper attire and conduct.

The chain of infection consists of six essential components: infectious agent (the microorganism causing disease), reservoir (where the microorganism lives and multiplies), portal of exit (how the microorganism leaves the reservoir), mode of transmission (how the infection spreads), portal of entry (how the microorganism enters the host), and susceptible host (a person who can become infected). Understanding this chain is fundamental to infection control, as breaking any link prevents disease transmission. Transmission-based precautions (contact, droplet, and airborne) are applied based on the mode of transmission, with contact precautions requiring gloves and gowning, droplet precautions requiring surgical masks, and airborne precautions requiring N95 respirators and negative pressure rooms.

Proper hand scrubbing decreases the risk of surgical site infections by approximately 92 percent. The duration of scrubbing varies depending on several factors including whether it's the first scrub of the day, the type of scrub brush being used, and whether a waterless cleanser or traditional soap-and-water cleanser is employed. A typical scrub may last anywhere from three to ten minutes. Newer or less experienced scrubbers should spend more time at the sink than others, as they are statistically more likely to make errors. It is advisable to finish scrubbing slightly after the attending to avoid appearing rushed or insufficiently prepared.

Surgical hand scrub involves: (1) Wet hands and forearms with water. (2) Apply antiseptic agent (chlorhexidine or iodine-based solution). (3) Scrub hands and forearms for 3-5 minutes (6 minutes total: 3 minutes per hand). (4) Scrub all surfaces: palms, backs of hands, between fingers, under fingernails, and wrists. (5) Scrub forearms up to the elbows. (6) Rinse hands and forearms thoroughly. (7) Dry hands and forearms with sterile towels. (8) Keep hands elevated above elbows to prevent recontamination. (9) Use sterile towels to turn off faucet.

Surgical hand scrub is a critical infection prevention procedure that removes debris and transient microorganisms from nails, hands, and forearms, reducing resident microbial count to a minimum; the technique involves removing all jewelry, washing hands and arms with antimicrobial soap for 6 minutes using a systematic approach where hands are kept higher than arms to prevent contamination, rinsing in one direction from fingertips to elbows, and drying with a sterile towel before gowning and gloving, with key rules including never touching non-sterile surfaces after scrubbing and avoiding common mistakes like entering the OR without a mask or wearing street shoes.

This section covers hand hygiene before aseptic procedures. Hand hygiene includes: (1) Using hydroalcoholic solutions (gel or liquid), (2) Following the 7 steps of hand hygiene, (3) Friction time of 20-30 seconds, (4) Using soap and water only if hands are visibly soiled (40-60 seconds), (5) Removing jewelry (except wedding rings), (6) Short fingernails without nail polish or fake nails, (7) Clean forearms. Hand hygiene before aseptic procedures is NOT equivalent to surgical hand scrub. Surgical hand scrub uses soap and water with 16 steps and 2-5 minutes duration. Hand hygiene is indicated before patient contact, after patient contact, after exposure to body fluids, and after contact with patient environment.

To perform a proper surgical hand scrub, wet hands and arms with water at a comfortable temperature while keeping fingers above elbows, apply Hibiclens scrub to a sterile sponge to create a thick lather, use the bristled side to scrub fingertips and nails with at least 30 strokes per hand, then use the sponge side to clean the palm and back of hands and each finger individually with at least 10 strokes per side, scrub wrists and arms up to 2 cm above elbows, and if fingers drop below elbows at any point, restart the entire process.

The correct sequence for donning PPE is: hand hygiene, gown, mask/respirator, goggles/face shield, gloves; for doffing: gloves, goggles/face shield, gown, mask/respirator, hand hygiene. When donning, always select appropriate PPE based on transmission-based precautions (droplet, airborne, or contact), and when doffing, remove contaminated items first while keeping clean areas intact, always removing respirators outside the patient's room after closing the door and performing hand hygiene immediately.

Proper PPE donning sequence is gown first, then mask/respirator, followed by goggles/face shield, and finally gloves, with hand hygiene performed before and during the process; the doffing sequence reverses this order (gloves, gown, face shield/goggles, mask/respirator), with critical emphasis on avoiding contact with contaminated outer surfaces and performing hand hygiene at each step to prevent infection transmission.

The correct sequence for donning (wearing) PPE is: (1) Gown first, (2) Mask, (3) Goggles/Face Shield, (4) Gloves last. The correct sequence for doffing (removing) PPE is: (1) Gloves first, (2) Gown, (3) Eye protection, (4) Mask and respirator last. This sequence prevents self-contamination during removal.

This video teaches nursing students the correct sequence for donning PPE (gown, mask, goggles, gloves) and two methods for doffing PPE to prevent cross-contamination: the CDC-approved method (remove gloves first, then goggles, then gown by pulling forward while keeping hands inside, then mask) and a more practical clinical method (remove gown first, then gloves over gown); students should practice by applying shaving cream to the outside of their PPE to verify they don't contaminate themselves during removal.

When putting on PPE, follow reverse alphabetical order with one exception: the mask is put on second. The correct sequence is: gown, mask, goggles, gloves. When removing PPE, follow alphabetical order: gloves, goggles, gown, mask. This sequence ensures maximum protection while minimizing contamination risks. The mask is put on second during donning because it is the most critical barrier for respiratory protection.