Subcutaneous hydration management

Patient Selection

Indications for use

  • Dehydration contributing to poor renal clearance of opioids which are causing symptoms of toxicity.
  • Dehydration due to drowsiness due to reversible causes (e.g. infection).
  • Inability to swallow e.g. advanced head and neck tumour, unsuitable for gastrostomy or other artificial feeding tube.
  • Symptoms due to dehydration that are not responding to other treatment (e.g. intractable nausea or vomiting, severe dry mouth or thirst, delirium).
  • To meet fluid requirements in the short term when oral intake is inadequate and maintaining an intravenous line is difficult or inappropriate.
  • Strong patient (or carer where the patient lacks capacity) informed preference for artificial hydration where there are no contraindications.

Confusion and restlessness can be occasionally aggravated by dehydration. However, quality evidence for use of subcutaneous fluids in these patients is lacking. A short trial for the individual patient may be indicated to assess for benefit.

There is insufficient evidence at present to indicate whether giving artificial hydration will extend life or prolong the dying process.

Cautions/ contraindications

  • Risk factors for fluid overload and existing ascites, heart failure or peripheral oedema due to hypoalbuminaemia.
  • Severe renal or hepatic failure.
  • Severe dehydration, shock or any condition requiring the rapid administration of fluids, in large volumes or when careful titration and monitoring of fluids is required (these patients should be given intravenous fluids).
  • Major bleeding or coagulation disorders.
  • If the patient is imminently dying hydration will not improve survival or symptom management and may increase the risk of distressing respiratory secretions.
  • For medication induced dry mouth.
  • Patient refusal including applicable advanced decision to refuse treatment or lack of consent from an attorney named as lasting power of attorney for health and welfare.

Patient and carer information, and managing expectations

For patients to give informed consent they should have a clear understanding of the following:

  • the purpose of using subcutaneous fluids
  • that the underlying disease process will continue and that further deterioration may be due to this rather than reduced fluid intake
  • how the decision will be made to stop the infusion (if appropriate)
  • possible side effects of peri-tumour oedema, cerebral oedema, peripheral oedema, ascites and peripheral pooling of fluid causing swelling and discomfort
  • possible side effects of increase in airway secretions causing a ‘death rattle’
  • possible side effects of increase in gastrointestinal secretions causing increase in nausea and vomiting
  • possible need for a urinary catheter

Discussion with patients/carers around the use of a ‘therapeutic trial’ of subcutaneous fluids with defined outcome measures e.g. improvement in symptom control (ideally as reported by the patient) could be explored prior to administration of fluids. This should include discussion about stopping fluids if symptom control goals are not achieved or if harm is caused. A discussion around ‘artificial sense of hope’ should also be explored with the family.

Managing complications

Increasing oedema may prompt review of risk benefit analysis or slowing of the rate of fluid infusion.

Where sodium chloride 0.9% is not being adequately absorbed hyaluronidase 1500 units may be given to improve absorption. It may be of benefit to patients in whom sites become quickly oedematous. It should not be used routinely as it can cause local irritation or systemic allergic reactions. To use hyaluronidase, dissolve 1500 units in 1ml water for injection or sodium chloride 0.9% and inject subcutaneously directly into the site to be used, then commence the infusion. Administer daily before infusion starts.

If a site becomes inflamed or infected, change infusion site, device or dressing and treat the inflammation/infection as appropriate to the patient’s condition.

Accidental bolus of infusions rarely occur and does not require further management, however a delay in the commencement of the next bag of sodium chloride 0.9% (so as not to go over the 2 litres in 24 hours) may be required.

Further information on the use of subcutaneous fluids can be obtained from the local specialist palliative care team.

Disclaimer (SPAGG - Rewrite)

This Guide is intended for use by healthcare professionals and the expectation is that they will use clinical judgement, medical, and nursing knowledge in applying the general principles and recommendations contained within. They are not meant to replace the many available texts on the subject of palliative care.

Some of the management strategies describe the use of drugs outside their licensed indications. They are, however, established and accepted good practice. Please refer to the current BNF for further guidance.

While WMPCPS takes every care to compile accurate information , we cannot guarantee its correctness and completeness and it is subject to change. We do not accept responsibility for any loss, damage or expense resulting from the use of this information.