An Urgent and Explosive Presentation - PowerPoint Presentation

Slide1

An Urgent and Explosive Presentation

Diane Williamson

Emergency Medicine Consultant

Addenbrooke’s

Hospital

October 6

th

ACCS Regional Training DaySlide2

Definitions

Diarrhoea

-

The frequent passage of unformed liquid stools (3 or more/day)Dysentery - Above plus blood or mucous in the stoolsAcute Gastroenteritis - Diarrhoeal disease of rapid onset characterised by nausea, vomiting, fever, abdominal painSlide3

Causes

Infections – Viral, bacterial, parasitic

Toxins

DrugsIBDMotility DisordersMalabsorption Food allergyNon-enteric – e.g. sepsisSlide4

Viral Gastroenteritis

Common

Benign and self-limiting for most

Life-threatening for othersSlide5

At Risk

Elderly

Infants

ImmunosuppressedConcomitant illnessSlide6

Epidemiology

Very high incidence

Leading cause of infant mortality worldwide

2 million hospital admissions>600 000 deathsBy age 3 effectively all children will become infected by the common agentsSlide7

Viral Gastroenteritis

Children – rotavirus most common (seasonal Nov to April)

Adults and children

rotavirus enterovirus adenovirus astrovirus (sporadic)

calicivirus

e.g.

norovirus

(outbreaks)

Faecal

-oral transmission of contaminated food and water

Norovirus

can be airborneSlide8

Pathophysiology

Virus enters villus enterocyte causing:

Osmotic

diarrhoea Structural damage to bowel mucosal villi causes maldigestion of carbohydrates and malabsorption of nutrients and waterSecretory diarrhoea Toxins (e.g. rotavirus NSP4) bind enterocyte causing causes Chloride ion secretionSlide9

Symptoms

Fever, malaise, fatigue, headache, lethargy

Abdominal pain and cramps

Nausea and vomitingLoss of appetiteWatery and frequent non-bloody stoolSlide10

Severity Assessment History

Deaths are caused by dehydration and acidosis

Frequency, quantity and duration of vomiting and

diarrhoeaOral intakeUrine outputWeight lossTravelSlide11

Severity Assessment Examination

Vital signs

Capillary refill

Mucous membranesReduced urine outputMental statusSevere abdominal tenderness or guarding suggest a surgical causeSlide12

Indications of bacterial infection

High fever

Bloody

diarrhoeaSevere abdominal pain(>6 stools/24 h)Slide13

Initial Investigations

Depend on severity – children and adults with minor symptoms need advice and reassurance, not investigation

In dehydrated or otherwise unwell patients

VBG – pH, electrolytes and glucoseUreaCreatinineAmylaseFBCConsider imagingSlide14

Specific Investigations

Rotavirus – stool antigen and antibody tests are available

Caliciviruses

(norovirus) – stool PCRC. difficile – stool C-diff and GDH toxinFaecal viral concentration correlates with duration and severity of illness and influences management and infection control measuresEarly stool sample is important – national stats are collected and Trust fined for in-hospital transmission beyond established thresholdsSlide15

Management

Oral hydration

IV hydration

Correct electrolyte disturbancesAntiemetics – generally not recommended but consider if symptoms prolongedConsider probiotics (some evidence for moderate symptom relief with Lactobacillus casei)Slide16

Prevention

Hand hygiene

Proper food handling

Clean water supplyRotavirus vaccineRotarix given at 8 and 12 weeks (liquid swallowed)Has prevented >70% of rotavirus cases6 years data, no safety concernsSlide17

Bacterial Gastroenteritis

Campylobacter

Clostridium

difficileE. coliSalmonellaShigellaV. choleraSlide18

Parasitic Causes

Entamoeba

hystoliticaGiardia lambliaCryptosporidiumSlide19

Reportable Diseases

Food poisoning

Infectious bloody

diarrhoeaReportable infectious agents (lab reports): Campylobacter Giardia lamblia Salmonella Shigella

Verocytotoxigenic

E coli

Vibrio choleraSlide20

Severe or Deteriorating PresentationsSlide21

Treat Shock

AB

C – access IV, IO

1L (Paed 20ml/kg) normal saline – reassess100ml (Paed 2ml/kg) 10% dextrose and infusionAntibiotics – treat sepsis Fluid replacement (remember to replace ongoing losses)Slide22

Electrolyte Disturbances

Hyponatraemia

(associated with administration of dilute oral rehydration fluids)

HypernatraemiaAcidosis – beware shifting potassium – as in DKA, K+ moves to extracellular space causing intracellular K+ depletion, review and replaceECG and monitor patient if K+ a concernSlide23

Hypokalaemia

K+ 3 - 3.5

mmol

/L: Start oral K+ replacement, or 20mmol KCl in 1000ml saline over 2-3 hoursK+ 2.5 – 3.0 mmol/L: Start 40 mmol/L over 4-6 hoursK+ <2.5 or ECG changes – prolonged QTc, Flat T-waves, high risk of arrhythmiaK+ <1.5mmol/L – paralysis, muscle weakness, apnoeaECG, cardiac monitor patients, consider

resusSlide24

Hyponatraemia

Na >125 mmol/L or mild symptoms

Rehydrate with 0.9% NaCl over 24 to 48 hours Recheck electrolytes 4 hourlySlide25

Hyponatraemia

Na <

125mmol/L

or severe symptomsRisks:Intracellular oedema, raised ICP, herniationWith rapid replacement and extracellular Na rise:Osmotic Demyelination Syndrome – duration is importantSlide26

Severe Hyponatraemia

Single

dose hypertonic saline over 1 hour

and review(e.g. 4ml/kg 3% saline up to 150ml)<48 hours duration, correct 1-2mEq/L/h for 4 hours to increase 4 to 6mEq/L, review

>48

hours duration,

as above but do

not exceed

0.5-1mEq/L/h and do not exceed 6 to 8mEq/L in 24 hours

Seizure

management – treat

hyponatraemia

and may have to repeat if seizures persist

Rapid

response/ICM

input for ongoing

managmentSlide27

Questions?