Sending Samples Kim Wilson Matron Infection Prevention UHMB

Sending Samples Kim Wilson, Matron, Infection Prevention UHMB] 12/03/2012

Introduction • What kind of samples do you send? • WHY?

Use of the Laboratory • • Blood Culture CSF Aspirates Sputum Swabs Urines Enterics • • Doctor “ “ Nurse “ “ “

A Few Myths • The laboratory diagnoses infection • The specimen always gets to the lab • Microbiology is instantaneous – Things take time to grow – Useful information before formal report • All laboratory reports are right • All laboratory reports require action

A Few Truths • We can easily grow bacteria from any body surface, but what does it mean? • The microbiology report only says what’s there, not what it means

What Can We Look For? 2 important concepts: n INFECTION • Bacteria are causing harm • Antibiotics MAY be required n COLONISATION • Bacteria are NOT causing harm • Antibiotics are NOT required • These are CLINICAL concepts that are assessed at the bedside, not in the laboratory. • Treat patients not bits of paper

How Does Infection Arise? • Contact with organism • Organism overcomes body defences (virulence, impaired defences) – – – – Malnutrition Immunocompromised Debility Diabetes Surgery Devices Antibiotics

Defining Infection SYSTEMIC SIGNS • Fever • Shock • Markers Neutrophilia, ESR, CRP LOCAL SIGNS • Pain • Swelling • Heat • Red Inflammation is not necessarily infection

Using the Laboratory • Blood Culture – Confirmation of sepsis - Not diagnosis – Care in collection - Contamination • Sputum – Invariably contaminated - Limited value – Aspirates / Endoscopy • Urine – Contamination Common – Bacteriuria is very common – and is not significant • Swabs – Colonisation

Collecting a Sample • Blood Culture ANTT • Urine MSU • Sputum Fresh • Swab From the wound bed

Why are samples not tested? Mainly • Labelling – either or both label and pot incomplete (or blank) • Mismatched form and pot (2 people) • No clinical indication identified Other issues • Wound swabs no identified location • DOB /NHS number/RTX do not match

The sooner we get it the better!

Thank you