Wound Assessment Part 2 Assessing the Wound for

Wound Assessment: Part 2 Assessing the Wound for Infection Dot Weir, RN, CWON, CWS

Objectives 1. Discuss the spectrum of bioburden in open wounds. 2. Describe the evolution of a biofilm 3. Name the steps in obtaining a meaningful wound culture

The Skin as Protection • Provides mechanical barrier to the invasion of bacteria and other pathogens into the deeper tissues • Skin oils, lipids and sweat help prevent invasion of bacteria into tissue • The skin surface is a relatively acidic environment (p. H 4 -6. 6), not supportive of bacterial growth • Skin cells shed into the environment keeping the bacteria at a tolerable level Stotts NA. Bioburden Infection, In: Baranoski S, Ayello EA. Wound Care Essentials, Practice Principles, 4 th edition, 2016 Lippincott Williams & Wilkins, Philadelphia

Defining Bioburden • Degree of microbial contamination or microbial load; the number of microorganisms contaminating an object 1 - Assumed to be quantified relative to the object • In wound management and wound healing, often a statement to the presence of bacteria on a wound as well as a qualitative descriptor of the bacterial status of the wound • As a result, it has also become a term used to document and consequently rationalize and support the use of various treatment alternatives - Specifically dressings and devices known to impact surface wound bacteria, such as antiseptics, antimicrobial dressings, and modalities such as ultrasound 1. Stedman’s Medical Dictionary

Describing Bacteria • Bacteria are described in a number of ways • • Shape Gram Stain Need, or lack of need, for oxygen Mode of growth

Shape • Great variation but 3 basic shapes Coccus: round or ball shaped Rod or bacillus: cylindrical Spirillum or spirochete: spiral shaped cylinder

Gram Stain • Staining technique for the early identification of bacteria Gram-positive cells have thick walls which will uptake crystal violet Gram-negative cells have thinner walls, do not hold violet dye, and retain counter-stained red color

Aerobic vs. Anaerobic • Do they require oxygen to survive? O 2 vs. O 2 © Dot Weir - Used with permission

Microbial States in Wounds • Contamination • • Colonization • • Presence of replicating organizations in the wound; no host immune response Critical Colonization/ Locally Infected • • Presence of non-replicating organizations in the wound; no host immune response Replicating organizations competing for resources, begin to see changes in the wound; biofilm forming; host tissue reaction Infection • Presence of replicating organizations in the wound with a host immune response © Dot Weir - Used with permission

What Does This Look Like? Sterile Infected Contaminated Colonized Critically Colonized

Critical Colonization • Presence of bacteria on the wound • Healing process compromised • No standard signs of infection • May delay healing via bacterial competition with tissue cells for oxygen and nutrients, production of bacterial toxins and inflammatory mediators • Also referred to as “locally infected” (vs. spreading infection)

Potential Signs of Critical Colonization • Granulation tissue • Color • Friability • Absent or abnormal • Odor – subtle or dramatic change • Failure to heal • Increased/high exudate levels in the presence of granulation tissue • Wounds attempt to “flush out” foreign particles or chemicals

Bacterial Growth • Planktonic: free floating, individual cells that work independently • Wound cultures are testing for planktonic growth • Most topical antimicrobial agents target planktonic growth • Antibiotics are developed to target specific sites to kill them • Easily transferred from one surface to another • Skin to wound • Contamination from outside source

Biofilms • Complex communities of bacteria (and other organisms) that adhere to solid surfaces (e. g. catheters) • Embedded in an extracellular polymeric substance • Have ability to survive in hostile environments • Contain different structures including channels in which circulation of nutrients can occur • Possess unique ability to communicate • Reduced metabolic activity leading to reduced metabolic needs • Systemic and most topical antibacterial/ antimicrobial agents cannot impact or kill

Predisposing Conditions that Contribute to Infections… • Damage of stratum corneum allowing for bacterial penetration • High concentration of bacteria • Immunocompromised host • Type of bacteria • Disruption of blood supply to the area • A favorable environment for bacteria • Moisture • oxygen/lack ©of oxygen • necrotic debris

Infection: Definition Invasion by and multiplication of pathogenic microorganisms in a bodily part or tissue, which may produce subsequent tissue injury and progress to overt disease through a variety of cellular or toxic mechanisms. http: //medical-dictionary. thefreedictionary. com/infection © Accessed 3/17/13

Infection: Clinical Picture • • • Swelling Induration Erythema Warmth Pain Odor

Assessment of Bacterial Burden © Dot Weir - Used with permission

Diagnosis • Diagnosing infection is a clinical skill and not a microbiologic technique • Culturing doesn’t tell you whether you have an infection or not; it identifies the organism and appropriate antibiotic • The culture is important but also need to focus on the host (the patient) and the wound environment

Method of Wound Culture • Biopsy • Aspiration • Swab © Dot Weir - Used with permission

Quantitative Tissue Biopsy • Historically the “gold standard” or at least best practice • Painful (may need anesthetic) • Skill intensive © Dot • Used more in research than clinical practice • >105 colony forming units (CFU) per gram of tissue considered to be infected © Dot Weir - Used with permission

Aspiration • Goal: obtain fluid for specimen below the surface of the wound • Skin is prepped (alcohol) • Needle inserted, fluid aspirated • Apply to swab

Improve Swab Technique • Thoroughly rinse wound surface with nonpreserved saline/cleaner • • Don’t swab through dressing residue, old exudate, necrotic tissue, blood Choose area that is free of non-viable tissue if possible Don’t bother with dry surfaces Place in carrier, transport ASAP

Methods of Swab Culture • Z Stroke • Levine’s Technique © Dot Weir - Used with permission • Goal is to get sampling of organisms on or in surface tissues of the wound • Necrotic tissue harbors large numbers of bacteria so should be avoided

Methods of Swab Culture • Z Stroke • • Less optimal Likely to pick up organism from necrotic tissue if present, skin edges © Dot Weir - Used with permission

Levine’s Technique • Surface swab of a one cm 2 area of healthy tissue in the wound • Press into wound to obtain fluid 1 cm area

Levine’s Technique

Location, Location… © Dot Weir - Used with permission • • Aim for clean area of the wound Avoid touching necrotic tissue © Dot Weir - Used with permission

Culture Reporting • Need to have the most information available to make sound decisions for treatment • Know the hospital/labs method of reporting cultures • • Gram Staining: automatically done or need to order separately? Qualitative Semi-quantitative Quantitative © Dot Weir - Used with permission

Culture Reporting • Gram Staining • • Provides early information as to the bacterial species likely to be present on the wound (not 100%) Also may indicate host response • Presence of white blood cells © Dot Weir - Used with permission

Culture Reporting • Qualitative Cultures: Presence of bacteria and antibiotic activities only © Dot Weir - Used with permission

Culture Reporting • Semi-quantitative cultures: Dish divided into 4 quadrants, serially streaked, and the number of quadrants with growth is reported © Dot Weir - Used with permission 1+ 2+ 4+ 3+ © Dot Weir - Used with permission

Culture Reporting • Quantitative cultures: provides actual colony forming units per gram of tissue of the bacteria identified in the wound. Usually needs tissue biopsy to determine. © Dot Weir - Used with permission

Key Nursing Concepts Ø Ø Ø Ø Assessment Caring Communication Ethics Evidence-based practice Infection Control Pain Patient Education Prevention Self Care Deficit Safety Tissue Integrity

Key Nursing Diagnoses Ø Potential for Alteration in Skin Integrity Ø Potential for Alteration in Tissue Integrity Ø Impaired Skin Integrity Ø Impaired Tissue Integrity Ø Oral Mucous Membranes, Altered Ø Knowledge Deficit r/t Ø Self Care Deficit r/t

Key Nursing Practice Issues • Registered Nurses (RN) assess wounds; Licensed Practice Nurses monitor wounds per state nurse practice acts • Accurate wound assessment and documentation is foundation for evaluating attainment of progress towards goal of care • Early recognition of a change in the bacterial load on an open wound is critical to prevent deeper infection • When culturing needed, attention to detail and getting a meaningful, usable culture is essential

Websites for Further Information on Wounds - Association for the Advancement of Wound Care www. aawc 1. org - Canadian Association for Wound Care www. cawc. net - National Pressure Ulcer Advisory Panel www. npuap. org - World Union of Wound Healing Societies www. wuwhs. org - Wound Ostomy Continence Nurses Society www. wocn. org

www. Why. Wound. Care. com