Topic 3: Introduction to prescription of intravenous fluids

Patient 1: Mrs Jaimee Jones

Case History:

25 yr female is day 1 post operative laparascopic appendicectomy and she is nil by mouth.

Past Medical History:

  • Asthma


  • Salbutamol 2 puffs PRN


  • Nil


  • BP 124/80
  • HR 85
  • RR 18
  • SpO2 99% RA
  • T 37.2C

Clinical examination:

  • Looks well,
  • JVPNE, MM dry
  • HSDNM,
  • Chest clear
  • Abdomen: Dressings on abdomen, distended, but soft, mildly tender. LL – no oedema.
  • Impression: Euvolemic

No blood tests available

Patient 2: Mrs Adele Sumwun

Case History:

75 yr female presents with acute on chronic renal failure, secondary to dehydration with ongoing vomiting and diarrhea.

Admission notes/ history of presenting complaint:

Mrs AS is 75 yr female who presents with acute on chronic renal failure, secondary to dehydration with ongoing vomiting and diarrhea.

For the past 3 days with cramping abdominal pain associated with diarrhea and vomiting. The diarrhea is loose, watery, unformed stools with no blood. She had buscopan to some effect. Vomiting was of initially ingested food, but is now watery, bile taste but no blood.

Past Medical History:

  • Chronic renal failure
  • Osteoporosis
  • Diabetes type II Medications:
  • Avapro 150/12.5 1 tab daily
  • Metformin 1g nocte
  • Calcitriol 0.25 micrograms daily


  • NKDA


  • BP: Lying 105/70
  • BP: Standing 85/65.
  • HR: 105 (SR),
  • RR: 20
  • SPo2: 97%
  • T: 37.6

Fluid Balance Chart

  • NS 1L q12h
  • Urine output 25-30mls/hour

Clinical examinations:

  • MM dry
  • JVPNE, seen at the base of the IJV at 45 degrees.
  • Skin turgor reduced
  • Weak pulse
  • Chest clear
  • Abdomen SNT
  • LL – no oedema.
  • Impression: Hypovolemic

Blood tests (hypovolaemic/dehydration)

Patient 3: Mr Harold Holter

Case History:

An 80yr male, with a background of congestive cardiac failure is nil by mouth day 1 post-laparotomy.

Clinical history/admission note:

  • Mr HH. 80 yr male
  • 2 day history of intense abdominal pain, nausea and vomiting
  • BNO in 5 days.
  • AXR- distended loops of bowel, with multiple fluid levels. No air in rectum.
  • 1 day post NG tube insertion- abdominal pain worsening with worsening distension
  • Large bowel obstruction – to theatre for laparotomy. Division of adhesions performed
  • Day 1 post laparotomy. Post op instructions: NBM
  • Mildly confused post op

Past Medical History:

  • CCF
  • IHD, AMI x 2 in 1999
  • COPD
  • HTN
  • High cholesterol
  • Diabetes
  • PVD
  • OA


  • Codeine


  • Captopril 150mg daily
  • Lasix 40mg daily
  • Lipitor 1 tab - Nocte
  • Novo mix 30 20 units BD
  • Panadol Osteo 1 tab BD
  • Pantoprazole 40mg daily


  • BP 180/70, HR 80- no postural drop
  • RR 23, SPO2 93%
  • T 37.4

Fluid Balance Chart

  • 5% Dextrose 1L q8h
  • UO 50mls/hour
  • Weight 100kg (normally 90kg)

Clinical examination

  • Bloated.
  • JVP elevated to angle of jaw
  • MM moist
  • Chest – crackles
  • Abdomen – distended, soft, some tenderness midline incision
  • LL – oedema to calves.
  • Sacral oedema.
  • Impression: Fluid overloaded

Blood tests (handout which demonstrates hyponatraemia)

Patient 4: Mr Cornelius Castle

Case History:

Mr CC is a 47 yr male with a colostomy; he is currently on total parenteral nutrition for malnutrition.

Clinical history/ admission information:

  • Mr CC is a 47 yr male who has a colostomy, formed in 2005.
  • Colostomy working adequately, no abdominal pain
  • He was admitted for malnutrition and total parenteral nutrition top up

Past Medical History:

  • Colon cancer with colostomy in 2005.
  • O.A






BP 100/90, HR 90 (no postural drop) Spo2 98%, RA, RR 17 A febrile

Fluid Balance Chart

  • TPN running ~ 60mls/hour
  • Has ileostomy ~ 250mls in bag
  • No IDC
  • Urine output 300ml over last 6 hours

Clinical Exam:

  • Looks well
  • Mucous membranes – moist
  • Chest clear
  • Abdomen soft
  • LL – no oedema
  • Impression: Euvolemic

Blood tests (handout that demonstrates hypokaleamia)

Patient 5: Mrs Momo Fooky

Case History:

Ms Momo Fooky is a 77 yr female who presents with dizziness, lethargy and witnessed fall at home. Clinical History: 5 day history of dizziness, lethargy and anorexia Today, stood up to go to bathroom with carer and collapsed, woke up on floor. Carer found her on ground and sat her up. She was coherent, orientated to time and place immediately after the fall. It was reported that she had not hit her head. There was no seizure like activity, any tongue biting or incontinence. The likely diagnosis was of syncope secondary to hypovolaemia.

Past medical history:

  • Hypertension
  • COPD
  • GORD
  • Migraine
  • Paroxysmal Atrial fibrillation
  • Diabetes


  • Frusemide 40mg daily (but occasionally takes 2 for ‘puffy ankles’)
  • Coversyl 2.5mg 1 daily
  • Pantoprazole 40mg daily
  • Warfarin
  • Gliclazide 80mg


  • Morphine


  • Lying SBP 110/60, HR 80
  • Sitting up SBP 803/58, HR 92
  • SpO2 95% on RA RR 20.
  • Temp 37.1

Clinical Examination:

  • Does not look unwell.
  • Pulse – weak,
  • Perfusion – cap refill ~ 3-4 seconds, peripherally cool
  • Dizzy on standing
  • MM – dry
  • Skin turgor reduced.
  • JVP not elevated, pulsation visible at the base of the neck.
  • Chest – some mild crepitations bibasally.
  • LL – SNT, no oedema
  • Impression: Hypovolemic

Blood tests (handout demonstrates hypernatraemia)

Case 1

  • Prescription of intravenous fluids in the uncomplicated surgical patient

Case 2

  • Prescription of intravenous fluids in the dehydrated patient and to factor in ongoing losses
  • How to perform an assessment of a patient’s fluid status.
  • Recognition of the signs and symptoms of dehydration

Case 3

  • Recognition of the patient that is fluid overloaded
  • Recognition of the patient with complex fluid requirements
  • Awareness that excessive intravenous fluids can cause fluid overload and hyponatraemia
  • Knowledge of the risk factors for developing hospital acquired hyponatraemia
  • Recognise the importance of reviewing fluid balance charts and ordering daily weighs to identify patients with fluid overload

Case 4

  • How to write fluid orders to safely replace potassium
  • How to supplement potassium orally
  • How often biochemistry needs to be ordered on patients receiving intravenous fluids

Case 5

  • Recognition of the patient with complex fluid requirements
  • How to prescribe fluids in a patient with hypernatraemia
  1. Avoiding common problems associated with intravenous fluid therapy. Hilton A, Pelligrino V, Scheinkestel C. MJA. 2008; 189(9):509-513.
  2. Intravenous fluid therapy in adults in hospital. NICE guidelines