1. Hypokalaemia Normal levels in blood: 3.5 – 5.0mmol/L (Jones, 2011)

2. Hypokalaemia: symptoms Palpitations Skeletal muscle weakness – cramps Paralysis, paraesthesias Constipation Nausea, vomiting Abdominal cramp Polyuria, nocturia, polydispepsia Psychosis, delerium, hallucinations Depression

3. Physical findings consistent with severe hypokalaemia (Garth et al., 2009) Ileus Hypotension Ventricular arrhythmia Cardiac arrest Bradycardia or tachycardia Premature atrial or ventricular beats Hypoventilation, respiratory distress Respiratory failure Lethargy Decreased muscle strength Decreased tendon reflexes Cushingoid appearence: oedema

4. Hypokalaemia: causes (Garth et al., 2009) Renal losses and leukemia GI losses – Diarrhoea and vomiting – Enema, laxative use – Ileal loop Medications – Diuretics – Beta adrenergic agonists – Steroids Transcellular shift – Insulin – Alkalosis Malnutrition – Decreased intake inc. Anorexia nervosa – Parenteral nutrition

5. Hypokalaemia: investigations (Garth et al., 2009) Serum K+ level <3.5mmol/L Creatinine Magnesium Digoxin use? – Hypokalemia can potentiate digitalis induced arrythmia ECG – T wave flattening – QT prolongation – ST segment depression – Ventricular and atrial arrythmia Thyroid function: TSH, free T3, free T4 ABC Cardiac monitoring

6. Hypokalemia: treatment (The Merck Manual; online) 1) oral potassium – Mild to moderate hypokalemia (2.5-3.5mmol/L) – Large dose = GI irritation so give divided doses – Wax impregnated preps better tolerated than liquid preps – take with or after food 2) IV potassium – Severe hypokalemia: ECG changes or severe symptoms – K+ solution irritate peripheral veins – Concentration should not be more than 40mmol/L 3) If Hypokalemia induced arrythmia can give more than 40mmol/L must use central vein or multiple peripheral veins MUST HAVE CONTINUOUS CARDIAC MONITORING AND HOURLY SERUM POTASSIUM Do not use glucose preparation due to insulin interference (may decrease K+ levels further) Normally between 100-120mmol/L K+ in 24 hours Regular Mg and Ca levels

7. Toxic megacolon (Devuni et al., 2009) a.k.a Toxic Megacolon: clinical term for acute toxic colitis “toxic colitis” preferred as possible without megacolon dilatation Potentially lethal Systemic toxicity Colonic dilatation = transverse colon >6cm

8. Toxic colitis (Devuni et al., 2009) 1 st criterion = x ray 2 nd criterion = any 3 of: – Fever – Tachycardia >120bpm – Leukocytosis 3 rd criterion = any 1 of: – Dehydration – Altered mental state – Electrolyte abnormality – hypotension

9. Toxic colitis (Devuni et al., 2009) Inflammatory causes – Ulcerative colitis, Crohn’s disease, pseudomembranous colitis Infectious colitis – Salmonella, Shigella, Compylobacter, Yesinia, C. Diff., Entanoeba Histolytica, Cytomegalovirus Other causes – Radiation colitis, ischaemic colitis, nonspecific colitis secondary to chemotherapy, complication of collangeous colitis (rare)

10. Toxic colitis: Investigations (Devuni et al., 2009) Nutrition & coagulation panel (group & save) in case surgery Imaging – x-ray then CT: loss of colinic haustrations, possible thumbprinting Other – ESR, CRP (usually increased). Nb. These findings are supportive not specific Do not do barium studies due to risk of perforation CBC counts Abdominal x-rays every 12 hours

11. Treatment of toxic colitis (Devuni et al., 2009) 1) reduce colonic distortion 2) correct fluid and electrolyte imbalance 3) treat toxemia and precipitating factors Fluid and electrolyte replenishment should be aggressive at first Start broad spectrum IV antibiotic e.g. Ampicillin Stop all meds that reduce colonic mobility e.g. Narcotics, antidiarrhoeals, anticholinergics Bowel rest consider NG tube. Can use long suction tube but needs fluro placement Start IV steroids –IV hydrocortisone for pts on steroids Rolling techniques to redistribute gas Cyclosporin A: last choice before surgery or if surgery not viable because hideous side effects

12. Toxic colitis: surgical intervention (Devuni et al., 2009) Early surgical consultation Consider if no improvement following 48-72 hrs with medical therapy Perform surgical resection Subtotal colectomy preferred: – Patient very ill; shorter procedure – Possibilty of ileoanal pouch formation – Approx. 50% Crohn’s patients no rectum involvement

13. Toxic colitis: surgical intervention (Devuni et al., 2009) Complications: Perforation after dilatation has reduced – Peritonitis not obvious if steroid use If only do med management = poor prognosis Surgical intervention before perforation = excellent results

14. Toxic colitis: patient education(Devuni et al., 2009) Patient Education: Nutrition (increase K+: bananas, peaches) IBD (Crohn’s + ulcerative colitis) Ostomy usually permanent – stoma care team

15. Toxic colitis: Nursing Priorities Careful and frequent monitoring Manual BP and pulse especially if GI patient: monitoring for bleeds (Christine Whitehead lecture – if patient tachy, monitor for BP drop - call doctor!) Fluid balance – I/O X-rays Repeat K bloods +Mg & Ca NG tube placement Rolling techniques Stoma care team involvement/referral if surgery an option Patient education

16. References Devuni et al., (2009; online @ medscape). Toxic Megacolon: Clinical presentation http://emedicine.medscape.com/article/181054- overviewhttp://emedicine.medscape.com/article/181054- overview Garth, D. Et al (2009; online @ medscape). Hypokalemia in Emergency Medicine: Clinical Presentation. http://emedicine.medscape.com/article/767448-overview http://emedicine.medscape.com/article/767448-overview Jones, H. (2011) Nursing and Health – Medical Abbreviations & Normal Ranges: Survival Guide. Pearson Education Ltd. Merck Manual (online) Disorders of potassium concentration: electrolyte disorders http://www.merckmanuals.com/professional/endocrine_and_meta bolic_disorders/electrolyte_disorders/disorders_of_potassium_con centration.html?qt=disorder%20potassium&alt=sh http://www.merckmanuals.com/professional/endocrine_and_meta bolic_disorders/electrolyte_disorders/disorders_of_potassium_con centration.html?qt=disorder%20potassium&alt=sh