Medicines Protocol HYPERTONIC SALINE 5%

Transcription

1 Medicines Protocol HYPERTONIC SALINE 5% HYPERTONIC SALINE 5% v1.0 1/4 Protocol Details Version 1.0 Legal category POM Staff grades Registered Paramedic Registered Nurse Specialist Paramedic (Critical Care) Specialist Nurse (Critical Care) Nurse Practitioner Advanced Technician Approved by Medicines Management Group Date issued Review date Clinical Publication Category PROTOCOL (RED) No deviation permissible. Clinical Requirements Continuing education The clinician is responsible for keeping him/herself aware of any changes to the recommendations for the medicine listed. It is the responsibility of the individual to keep up-to-date with continued professional development and to work within the limitations of their own individual scope of practice.

2 HYPERTONIC SALINE 5% v1.0 2/4 Clinical Situation Clinical situation Treatment with hypertonic saline (HS) 5% intravenous injection must be implemented only as a bridge between prehospital care and neurosurgery. Administration is only legally valid on the prescription of a medical practitioner. The prescription may be taken on a recorded line as a verbal order. HS is only indicated in a patient with a head injury requiring direct transfer to a neurosurgical unit (unless airway or circulation are unmanageable). i.e. When it is necessary to improve intracranial pressure in traumatic brain injury (TBI) and/or when there is evidence of coning. Inclusion criteria Adults and children, who have a current prescription for HS given by a medical practitioner on a recorded line and who have: TBI and a GCS<8 and systolic BP<90 (or no palpable radial pulse). Evidence of coning despite maximal therapy in a patient with a head injury (GCS<8) one or two fixed dilated pupils or bradycardia. Exclusion criteria Adults and children, who do have a current prescription for HS given by medical practitioner on a recorded line and who have: TBI and a GCS<8 and systolic BP<90 (or no palpable radial pulse). Evidence of coning despite maximal therapy in a patient with a head injury (GCS<8) one or two fixed dilated pupils or bradycardia. Adults and children, who have a current prescription for HS given by a medical practitioner on a recorded line but who do not have: TBI and a GCS<8 and systolic BP<90 (or no palpable radial pulse). Evidence of coning despite maximal therapy in a patient with a head injury (GCS<8) one or two fixed dilated pupils or bradycardia. Rationale Traumatic brain injury (TBI) is the result of a primary, acute injury and is complicated by the development of secondary injury due to hypotension and hypoxia. Cerebral oedema due to brain injury compromises the delivery of essential nutrients and alters normal intracranial pressure. Raised Intra-Cranial Pressure (ICP) following a TBI has shown to be a powerful predictor of neurological deterioration and often associated

3 HYPERTONIC SALINE 5% v1.0 3/4 with poor outcomes. Hyperosmolar therapy is a commonly used treatment for intracranial hypertension due to cerebral oedema, primarily as a bridge to imminent neurosurgical intervention. The most commonly used hyperosmolar therapies are Mannitol and Hypertonic Saline (HS). Mannitol and HS are osmotic solutions which elevate blood plasma osmolality, resulting in enhanced flow of water from tissues, including the brain and cerebrospinal fluid, into interstitial fluid and plasma. As a result, cerebral oedema, elevated intracranial pressure, and cerebrospinal fluid volume and pressure may be reduced. The Brain Trauma Foundation and the European Brain Injury Consortium currently recommend Mannitol as the treatment in the management of intra-cranial hypertension. Mannitol is an osmotic diuretic that is metabolically inert in humans and occurs naturally, as a sugar or sugar alcohol, in fruits and vegetables. Mannitol has long been the "gold standard" for treatment of cerebral oedema and refractory intracranial hypertension in traumatic brain injury but studies performed in animals have shown that hypertonic saline (HS), in doses ranging from 3% to 10%, may be more effective than Mannitol in treating these populations. Randomised clinical trials have evaluated the efficacy and safety of HS versus Mannitol in the treatment of elevated intracranial pressure (ICP). This research has been prompted by mounting concern about the side effects of Mannitol, the limited ability to give multiple doses of the drug, and an increased understanding of cerebral physiology. Four studies have compared the use of HS and Mannitol in brain-injured populations. These studies have shown that not only is HS a safe drug (no patients experienced adverse effects), it is also more efficient in reducing ICP. Efficiency is defined as the drug's ability to decrease ICP to acceptable levels and to maintain lower ICPs for a longer duration of time. HS solutions have, therefore, evolved as an alternative to Mannitol to treat raised intracranial pressure. With high osmolar loads, the efficacy of the solution is enhanced, but no simple relationship between the saline concentration and the clinical effects of a solution has yet been definitively established. There is a wide variation from 2% to 23.5%, in the reported concentration of HS for clinical use. Consequently, a Trust Patient Group Direction cannot be provided for this unlicensed indication of a licensed medicine. HS is currently the preferred choice of the neurosurgical units in the South West. The local neurosurgical units (North Bristol NHS Trust and University Hospital of Southampton NHS Foundation Trust) are both using 5% HS.

4 Caution HYPERTONIC SALINE 5% v1.0 4/4 Caution is required with high osmolar loads because they carry increased risks for potentially deleterious consequences of hypernatremia or may induce osmotic blood-brain barrier opening with possibly harmful extravasation of the hypertonic solution into the brain tissue. Patients with sodium overload. This may occur with myocardial and renal damage, but it should also be appreciated that in the first five or six days after surgery or severe trauma there may be an inability to excrete unwanted sodium. Repeat the prescriber s instructions for the administration of HS back to them before accepting the prescription. Where electronic technology permits written instructions these should be used to support the message on the recorded line. Do not use unless the solution is clear and free from particles. Incompatible with amiodarone, amphotericin B, amsacrine and sodium nitroprusside. Do not administer these drugs in the same line. Side effects A too rapid injection of hypertonic saline may cause sudden cardiac arre or circulatory overloading. Thrombosis of the chosen vein is always a possibility with intravenous infusion. Action if excluded If patient meets exclusion criteria transport as a time critical emergency t the nearest appropriate hospital. Record reason in Patient Clinical Record. Action if patient declines If patient declines treatment transport as a time critical emergency to the nearest appropriate hospital. Record in Patient Clinical Record. Description of Treatment Generic name Presentation Sodium chloride Injection 5% 500ml Polyfusor Route Intravenous

5 Administration Supply HYPERTONIC SALINE 5% v1.0 5/4 Method Check the strength of the chosen infusion. Ensure adequate oxygenation and CO 2 control. Position head up at 30 degrees (if possible). Administer sedation. Ensure adequate venous drainage (e.g. loosen a tight-fitting cervical collar). Hypertonic saline should be administered via a 3-way tap, handinfusing with a 50ml syringe into the largest vein possible over 10 to 20 minutes. Monitor for signs of extravasation. Observe carefully observed as HS can cause tissue necrosis. Using a 3-way tap helps to avoid accidental overdose. Dose The dose is the responsibility of the prescriber but is usually 3ml/Kg Duration of treatment Single episode of care llow Up Referral arrangements and safety netting Time critical transfer to neurological unit. Records Complete patient clinical record. References Infanti, JL (2008) Challenging the gold standard: should mannitol remain our first-line defense against intracranial hypertension? Journal of Neuroscience Nursing 2008 Dec;40(6): Mortazavi et. al. (2012), Hypertonic saline for treating raised intracranial pressure: literature review with meta-analysis, Journal of Neurosurgery, 116: Rickard et. al.(2014), Salt or sugar for your injured brain? A meta-analys of randomised controlled trials of mannitol versus hypertonic sodium solutions to manage raised intracranial pressure in traumatic brain injury, Emergency Medicine Journal, 31:

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