Heparin: Therapeutic Unfractionated Heparin (UFH) Infusion Procedure

Transcription

1 Prcedure Heparin: Therapeutic Unfractinated Heparin (UFH) Infusin Prcedure 1. Purpse This dcument utlines the prcedure details fr the cmmencement and maintenance f unfractinated heparin (UFH) infusins at the Wmen s. It may be necessary t mdify this prcedure accrding t individual patient requirements. 2. Definitins Nt applicable. 3. Respnsibilities All staff invlved with the prescribing, supply and administratin must be aware f this guideline t ensure the safe and apprpriate use f heparin infusin. This includes: medical staff nursing and midwifery staff pharmacy staff. 4. Prcedure 4.1 The indicatins fr therapeutic unfractinated heparin (UFH) include the fllwing: treatment f acute venus thrmbemblism in the medically unstable patient r fr patients where labur r surgery is imminent preventin f arterial thrmbemblism in medically unstable patients with cardiac arrhythmias and/r presumed emblic strke peripartum r periperative anticagulatin in wmen with prsthetic heart valves. 4.2 Prescriptin UFH can be administered by intravenus r subcutaneus rutes. This guideline applies t the intravenus rute nly. UFH is cmpatible with 5% Dextrse and 0.9% sdium chlride (NaCl). Premixed heparin infusin bags cntaining 25,000 units in 250mL sdium chlride 0.9% (100 units/ml) are available. * Heparin infusin rders shuld include the dse written as units/kg/hur and the crrespnding ml/hur rate. Obtain patient weight. Obtain baseline FBE, APTT and PT. Any patient with a lw platelet cunt r an abnrmal APTT r INR shuld be discussed with a haematlgist prir t starting heparin. A lading dse f heparin = 80 units/kg t a maximum f 5000 units ver 10 minutes is usually prescribed. This may be mitted in patients at increased risk f bleeding. A typical maintenance infusin = 18 units/kg/hr. Patients with renal failure will require mdified dses. Cnsult with Haematlgy. 4.3 Administratin Equipment: Heparin 5000 units in 5mL ampules (fr initial blus and repeat blus dses) Heparin infusin bag 25,000 units in 250mL sdium chlride 0.9% (100 units/ml) (cmmercially available premixed bag). * Patients shuld have a dedicated line fr heparin infusins. The infusin must nt be stpped r interrupted fr ther medicines. APTT bld samples shuld be drawn frm the cntra-lateral arm. Uncntrlled dcument when printed Publicatin Date: (18/05/2017) Page 1 f 6

2 Prcedure Heparin: Therapeutic Unfractinated Heparin (UFH) Infusin Prcedure Lading dse (80units/kg t maximum f 5000units) Intravenus injectin: administer the required heparin lading dse accrding t the table belw based n patient weight by slw IV injectin. Using: Heparin 5000 units in 5mL ampule (1000 unit/ml). Patient weight Lading dse = 80 units x kg t maximum f 5000 units Vlume f lading dse (IV injectin) kg units ml > >100 Cntact Haematlgist Uncntrlled dcument when printed Publicatin Date: (18/05/2017) Page 2 f 6

3 Prcedure Heparin: Therapeutic Unfractinated Heparin (UFH) Infusin Prcedure Maintenance Dse (18units/kg/hr) Intravenus infusin: Premixed heparin infusin bags f 25,000 units in 250mL sdium chlride 0.9% (100 units/ml) shuld be used and infused at the required rate using an infusin pump with guardrails. Once the lading dse has been cmpleted, cnfigure the infusin pump t accept the 25,000 units in 250mL premixed heparin infusin bag (cncentratin = 100 units/ml). Set the weight f the patient and the pump rate t infuse maintenance dse (ml/hr) accrding t the table belw: Patient weight Maintenance dse = 18 units x kg / hr Rate f infusin = [(maintenance dse 25000) x 250mL] / hr kg units/hr ml/hr Uncntrlled dcument when printed Publicatin Date: (18/05/2017) Page 3 f 6

4 Prcedure Heparin: Therapeutic Unfractinated Heparin (UFH) Infusin Prcedure 4.4 Nmgram fr adjusting heparin dse (dse adjustment t be decided by medical fficer) APTT (secnds) BOLUS (units/kg) HOLD (minutes) RATE CHANGE (units/hr) REPEAT APTT < Increase 20% 4 hurs Increase 10% 4 hurs N change 24 hurs Reduce 10% 4 hurs Reduce 10% 4 hurs > Reduce 15% 4 hurs 4.5 Mnitring f therapy Heparin is usually mnitred by APTT. The therapeutic range crrespnds t times the nrmal APTT (usually secnd). A mdified target range may be determined by the haematlgist in patients at increased risk f bleeding The MAXIMUM interval between APTT assays shuld nt exceed 24 hurs. The APTT may be inaccurate in certain clinical circumstances. An alternative is an anti Xa assay. The therapeutic range fr the UFH anti Xa assay is units/ml. NOTE: the UFH anti Xa is a different therapeutic range cmpared t the LMWH assay. Results cannt be interchanged. Request frms must indicate the type f heparin being used. APTT bld samples Bld samples can NOT be drawn frm the same line as the heparin infusin. Cagulatin tubes must be filled exactly t the specified mark. Twice weekly FBEs, (platelet cunt) are required. If there is an abrupt decrease in platelet cunt, (e.g. 50%) cnsider Heparin Induced Thrmbcytpaenia (HIT), cease all heparin administratin and immediately cntact haematlgist n call. Duratin f therapy The duratin f heparin therapy is dependent upn the primary prblem. Please cnsult the Haematlgy department fr guidelines. Precautins during heparin therapy Avid aspirin and ther anti-platelet medicines during heparin therapy. Avid IM injectins and arterial stabs during anticagulant therapy. When such prcedures are clinically necessary, ensure adequate external pressure is applied pst-prcedure. Uncntrlled dcument when printed Publicatin Date: (18/05/2017) Page 4 f 6

5 Prcedure Heparin: Therapeutic Unfractinated Heparin (UFH) Infusin Prcedure 4.6 Neuraxial anaesthesia Intravenus UFH infusin shuld be ceased 4-6 hurs befre epidural catheter insertin r spinal injectin. A nrmal APTT and platelet cunt shuld be dcumented befre the prcedure ccurs. 4.7 Adverse events The majr adverse event ptentially related t standard heparin infusin is bleeding. If a patient n heparin develps bleeding, cease heparin infusin and seek urgent Haematlgy cnsult. 4.8 Heparin antidte If anticagulatin with heparin needs t be discntinued fr clinical reasns, terminatin f the heparin infusin will usually suffice. If an immediate effect is required, cnsider administering prtamine sulfate. Prtamine is a medicine that requires a high level f cautin when being prescribed and administered. Prtamine sulfate neutralises heparin by virtue f its psitive charge. Fllwing IV administratin, neutralisatin ccurs within 5 minutes. The dse f prtamine sulfate is based n the amunt f heparin received in the previus 2 hurs as fllws: Time since last heparin dse Prtamine dse (mg) per 100 Units heparin received Maximum Dse f prtamine < 30 min min 1 mg mg The maximum dse f prtamine, regardless f the amunt f heparin received is 50mg except fr reversal f min mg heparin fllwing cardipulmnary bypass >120 min mg Prtamine administratin Prtamine sulfate is usually administered by slw IV injectin in a cncentratin f 10mg/mL at a rate nt t exceed 5mg/minute. If administered t quickly, prtamine sulfate may cause cardivascular cllapse. Patients with knwn hypersensitivity reactins t fish, and thse wh have received prtamine-cntaining insulin r previus prtamine therapy may be at risk f hypersensitivity reactins t prtamine sulfate. Obtain bld fr PT and APTT 15 min after the administratin f prtamine sulfate. 5. Evaluatin, mnitring and reprting f cmpliance t this prcedure Cmpliance t this prcedure will be mnitred, evaluated and reprted thrugh: the VHIMS nline incident reprting system, clinical audit. 6. Reference 1. Lackie CL, Luzier AB, Dnvan JA, Feras HI, Frrest A. Weight-based heparin dsing: clinical respnse and resurce utilizatin. Clin Ther Jul-Aug;20(4): Uncntrlled dcument when printed Publicatin Date: (18/05/2017) Page 5 f 6

6 Prcedure Heparin: Therapeutic Unfractinated Heparin (UFH) Infusin Prcedure 2. Raschke RA, Reilly BM, Guidry JR, Fntana JR, Srinivas S. The weight-based heparin dsing nmgram cmpared with a "standard care" nmgram. A randmized cntrlled trial. Ann Intern Med Nv 1;119(9): Myzienski AE, Lutz MF, Smythe MA. Unfractinated heparin dsing fr venus thrmbemblism in mrbidly bese patients: case reprt and review f the literature. Pharmactherapy Mar;30(3): Smith ML, Wheeler KE. Weight-based heparin prtcl using antifactr Xa mnitring. Am J Health Syst Pharm Mar 1;67(5): Legislatin related t this guideline Nt applicable. 8. Appendices Nt applicable. PGP Disclaimer Statement The Ryal Wmen's Hspital Clinical Guidelines present statements f 'Best Practice' based n thrugh evaluatin f evidence and are intended fr health prfessinals nly. Fr practitiners utside the Wmen s this material is made available in gd faith as a resurce fr use by health prfessinals t draw n in develping their wn prtcls, guided by published medical evidence. In ding s, practitiners shuld themselves be familiar with the literature and make their wn interpretatins f it. Whilst appreciable care has been taken in the preparatin f clinical guidelines which appear n this web page, the Ryal Wmen's Hspital prvides these as a service nly and des nt warrant the accuracy f these guidelines. Any representatin implied r expressed cncerning the efficacy, apprpriateness r suitability f any treatment r prduct is expressly negated In view f the pssibility f human errr and / r advances in medical knwledge, the Ryal Wmen's Hspital cannt and des nt warrant that the infrmatin cntained in the guidelines is in every respect accurate r cmplete. Accrdingly, the Ryal Wmen's Hspital will nt be held respnsible r liable fr any errrs r missins that may be fund in any f the infrmatin at this site. Yu are encuraged t cnsult ther surces in rder t cnfirm the infrmatin cntained in any f the guidelines and, in the event that medical treatment is required, t take prfessinal, expert advice frm a legally qualified and apprpriately experienced medical practitiner. NOTE: Care shuld be taken when printing any clinical guideline frm this site. Updates t these guidelines will take place as necessary. It is therefre advised that regular visits t this site will be needed t access the mst current versin f these guidelines. Uncntrlled dcument when printed Publicatin Date: (18/05/2017) Page 6 f 6