Intravenous Fluid Therapy in the Adult Patient

Publication: 15/03/2016  
Next review: 02/04/2022  
Clinical Guideline
ID: 4542 
Approved By: Trust Clinical Guidelines Group 
Copyright© Leeds Teaching Hospitals NHS Trust 2019  


This Clinical Guideline is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.

Intravenous Fluid Therapy in the Adult Patient

Summary of Guideline/Protocol

This guideline in devised to standardise and optimise the prescription of intravenous fluid therapy for the adult patient.

The guideline is based on the National Institute of Care and Health Excellence (NICE) Intravenous Fluid Therapy guideline (CG174) and the NICE quality standard 66 Intravenous Fluid Therapy in Adults in Hospital (66).

It includes guidance on the assessment of volume status and the appropriate prescription of intravenous fluids.

Back to top


The purpose of this guideline is to provide clear and concise advice with respect to the prescription of intravenous fluids for the adult patient.

The guideline is based on the National Institute of Health and Care Excellence (NICE) Intravenous Fluid Therapy guideline (CG174) and the NICE quality standard 66 Intravenous Fluid Therapy in Adults in Hospital (66) (1,2).

For more detailed guidance on intravenous fluid therapy the reader should refer to the NICE guidance available at

It is important to emphasise that the recommendations do not apply to

  • patients under 16 years
  • pregnant women
  • patients with severe liver disease
  • patients with severe renal disease
  • patients with diabetes mellitus
  • patients with burns
  • patients needing inotropes and those on intensive monitoring, and so they have less relevance to intensive care settings and patients during surgical anaesthesia
  • patients with traumatic brain injury (including patients needing neurosurgery)

Back to top


Determine whether intravenous fluids are required by clinically assessing the volume status of the patient (algorithm 1):

  • Capillary refill
  • Pulse rate (tachycardia may be masked by beta-blockers)
  • Blood pressure (lying and standing)
  • Jugular venous pressure
  • Skin turgor (over the clavicle)
  • Oedema (pulmonary, peripheral)
  • Fluid balance charts – including urine output
  • Daily weights (trends)

Passive leg raising is a bedside method to assess fluid responsiveness in a patient. It is best undertaken with the patient initially semi-recumbent and then tilting the entire bed through 45°. Alternatively it can be done by lying the patient flat and passively raising their legs to greater than 45°. If, at 30–90 seconds, the patient shows signs of haemodynamic improvement, it indicates that volume replacement may be required. If the condition of the patient deteriorates, in particular breathlessness, it indicates that the patient may be fluid overloaded.

Determine the nature of intravenous therapy required which may be:

Back to top


See section below on monitoring

Treatment / Management

Resuscitation Fluid Therapy
Intravenous fluids will be required to restore and maintain the circulation and the function of vital organs if the patient is hypovolaemic e.g.

  • blood loss from injury or surgery
  • acute pancreatitis
  • gastrointestinal or renal losses of salt and water.

Infuse 500mls (250mls if cardiac failure) over 15 mins of a

  • balanced crystalloid (e.g. Hartmann’s solution) or
  • 0.9% sodium chloride

(Appendix 1)

Hartmann's Solution is suggested as the first choice resuscitation fluid but the priority is to re-establish haemodynamic stability through restoring the intravascular volume and therefore if not available 0.9% sodium chloride can be used initially.

0.9% sodium chloride is preferred if

  • Potassium > 5.5mmol/L and the patient is not monitored on an HDU or ICU environment   or
  • AKI is secondary to rhabdomyolysis due to the risk of hyperkalaemia

Consider human albumin solution 4–5% for fluid resuscitation only in patients with severe sepsis. This must be discussed with a consultant.

The clinical response should be assessed immediately following administration of the fluid bolus by reassessing the volume status:

  • capillary refill time (reduction)
  • pulse (reduction in pulse if tachycardic)
  • jugular venous pressure (rise in JVP)
  • blood pressure (rise in BP)
  • pulmonary oedema
  • urine output (increasing if oliguric)

If no clinical response and no pulmonary oedema:
Administer further 500ml of crystalloid and reassess clinically and discuss with senior member of team (SpR or consultant).

If a clinical response to the fluid bolus:
Continue with IV fluids and discuss further fluid therapy management plan with senior member of team (SpR or consultant).

Volume unresponsive AKI:
If the patient develops oliguric AKI (urine output < 0.5 mls/kg/hr) despite adequate volume resuscitation consider the patient as having volume unresponsive AKI.
Further excessive fluid resuscitation may result in pulmonary oedema. Continue with IV fluid cautiously, matching urine output and monitoring for signs of respiratory distress (rising respiratory rate, pulmonary oedema or falling oxygen saturations). Request advice a senior member of team (SpR or consultant).

Specific Clinical Scenarios:


0.9% sodium chloride is the fluid of choice for intravenous fluid resuscitation after gastric losses, due to the high chloride content of gastric secretions.


In the case of major blood loss it is necessary to cross match and to give packed cells. Resuscitation with packed cells, fresh frozen plasma and platelets in a ratio of 1:1:1 has been shown to be more beneficial than packed cells alone, as this helps correct the associated coagulation defects.

Early and adequate treatment of the underlying cause of fluid loss, e.g. control of bleeding is vital.

For further information refer to the LTHT Transfusion in Massive Haemorrhage (Adults).

Continued resuscitation fluid therapy:

If 0.9% sodium chloride has been used initially conversion to a balanced crystalloid can be considered once potassium levels are known and good urine output established.

Once resuscitation of the volume status has been achieved as assessed by normalisation of vital signs and urine output or of parameters from more invasive measurements, the prescriber should switch to a Routine Maintenance regimen with accurate replacement of any on-going losses.

Routine Maintenance Fluid Therapy:
Maintenance prescriptions should aim to replace insensible daily loss (500-1000 ml), provide sufficient water and electrolytes to maintain normal status of body fluid compartments, and sufficient water to enable the kidney to excrete waste products 500-1500 ml/24 hours.

The average daily requirements are

  • 25-30 ml/kg water
  • 1 mmol/kg Sodium
  • 1 mmol/kg Potassium

An example of a daily maintenance regimen would be:

1.5 - 2 litres of 4% glucose/0.18% sodium chloride with 40mmol/L potassium chloride.

Careful monitoring is recommended to avoid the development of hyponatraemia.

Patients on longer-term IV fluid therapy whose condition is stable may be monitored less frequently, although decisions to reduce monitoring frequency should be detailed in their IV fluid management plan

Replacement Fluid Therapy:
An intravenous fluid prescription should incorporate not only daily maintenance requirements, but replacement of any ongoing abnormal losses.

In order to achieve this, the prescriber should be aware of the approximate electrolyte content of fluid from various parts of the gastrointestinal tract and other organ systems (Appendix 2)

Redistribution Fluid Therapy:
This applies to patients who with significant comorbidity or who have abnormal fluid and or electrolyte distribution, or example:

  • gross oedema
  • severe sepsis
  • hyponatraemia
  • hypernatraemia
  • renal, liver and/or cardiac impairment
  • post-operative fluid retention and redistribution
  • malnourished and refeeding issues

It is important to assess the patient’s intravascular volume status and recognise that in some cases these patients remain hypovolaemic despite having fluid in the interstitial space e.g. peripheral oedema.

Fluid therapy in these patients is challenging and expert help should be sought.

Prescribing and monitoring
Assess and manage patients’ fluid and electrolyte needs as part of every ward review

Patients receiving intravenous fluid therapy in hospital must have an intravenous fluid management plan detailed in the notes determined by and reviewed by an expert, which includes the fluid and electrolyte prescription over the next 24 hours and arrangements for assessing patients and monitoring their plan.

The prescriber should review the clinical data each time a new prescription is required

  • IV fluids should not be prescribed for more than 24 hours
  • IV fluid requirements should be reviewed daily to include
    • volume status assessment
    • assessment of urea and electrolytes to identify the development of electrolyte abnormalities e.g. hyponatraemia

Back to top

Critical Incidents

Critical incidents

Clear incidents of fluid mismanagement (for example, unnecessarily prolonged dehydration or inadvertent fluid overload due to IV fluid therapy) should be reported through standard critical incident reporting to encourage improved training and practice.


Back to top

Training and education

Hospitals should establish systems to ensure that all healthcare professionals involved in prescribing and delivering IV fluid therapy are trained on the principles covered in this guideline, and are then formally assessed and reassessed at regular intervals to demonstrate competence in:

  • understanding the physiology of fluid and electrolyte balance in patients with normal physiology and during illness
  • assessing patients' fluid and electrolyte needs (the 5 Rs: Resuscitation, Routine maintenance, Replacement, Redistribution and Reassessment)
  • assessing the risks, benefits and harms of IV fluids
  • prescribing and administering IV fluids
  • monitoring the patient response 
  • evaluating and documenting changes and taking appropriate action as required

Back to top


Record: 4542

To standardise and optimise the prescription of intravenous fluid therapy for the adult patient through helping prescribers understand the

  • physiological principles that underpin fluid prescribing
  • pathophysiological changes that affect fluid balance in disease states
  • indications for intravenous (IV) fluid therapy
  • reasons for the choice of the various fluids available
  • principles of assessing fluid balance

The term 'expert' refers to a healthcare professional who has core competencies to diagnose and manage acute illness

The purpose of this guideline is to provide clear and concise advice to all medical healthcare professionals with respect to the prescription of intravenous fluids for the adult patient.

Back to top

Clinical condition:

Intravenous Fluid Therapy in the Adult Patient

Target patient group:

Target patient group: All adult patients requiring intravenous fluid therapy In Leeds Teaching Hospitals Trust

Excluding patients under 16 years, pregnant women, patients with severe liver disease, severe renal disease, diabetes mellitus, patients with burns, patients with traumatic brain injury (including patients needing neurosurgery), patients needing inotropes and those on intensive monitoring e.g.intensive care settings and patients during surgical anaesthesia

Target professional group(s): Secondary Care Doctors
Adapted from:

Evidence base

References  and Evidence levels:

  1. Intravenous Fluid Therapy Clinical Practice Guideline  (CG 174)             
  2. Intravenous Fluid Therapy in Adults in Hospital 66

A. Meta-analyses, randomised controlled trials/systematic reviews of RCTs
B. Robust experimental or observational studies
C. Expert consensus.
D. Leeds consensus. (where no national guidance exists or there is wide disagreement with a level C recommendation or where national guidance documents contradict each other)

Back to top

Approved By

Trust Clinical Guidelines Group

Document history

LHP version 1.0

Related information

Appendix 1: Algorithms1-4 for intravenous fluid therapy in adults

Back to top

Back to top

Back to top

Back to top

Back to top

Appendix 2: Composition of electrolytes in commonly used crystalloids

Back to top

Appendix 3: Diagram of ongoing fluid and electrolyte losses

Back to top

Equity and Diversity

The Leeds Teaching Hospitals NHS Trust is committed to ensuring that the way that we provide services and the way we recruit and treat staff reflects individual needs, promotes equality and does not discriminate unfairly against any particular individual or group.