Hypertension - Management of Acute

Transcription

1 Hypertensin - Management f Acute 1. Purpse Severe hypertensive disrders f pregnancy are assciated with high rates f maternal and fetal mrbidity and mrtality. It is imperative in this clinical situatin that severe bld pressure in pregnancy is treated. This guideline prvides infrmatin abut the use and administratin f ral Nifedipine, intravenus labetall and when labetall is cntraindicated, the use and administratin f intravenus hydralazine. Als refer t Prcedure: Observatins Birth Centre Adult Escalatin Criteria and Respnse Framewrk. Where prcesses differ between campuses, thse that refer t the Sandringham campus are differentiated by pink text r have the heading Sandringham campus. 2. Definitins Hydralazine is a peripheral vasdilatr that causes relaxatin f arterilar smth muscle, which results in a lwering f bld pressure. The hyptensive effect ccurs within 5-20 minutes. Maximum effect is minutes and the duratin is 2-6 hurs. The nset f the drug s actin is within 15 minutes, with a peak effect between 30 and 60 minutes. Duratin lasts between 4 and 6 hurs. Because f the slwer nset, a lading dse is required. Labetall is a nn-selective beta-adrenergic blcking agent, prducing dse-related falls in bld pressure withut reflex tachycardia and withut significant reductin in heart rate. Onset f actin f intravenus labetall is at five minutes. Peak effect ccurs at minutes. Duratin f actin is 45 minutes t six hurs. A fluid pre-lad is advisable t cunteract the ptential fr a sudden decrease in bld pressure. Nifedipine is a calcium in influx inhibitr (calcium channel blcker r calcium channel antagnist). After ral administratin, the nset f actin is 1.5 t 4.2 hurs. The half-life f an immediate release dse frm shws a mean f apprximately 1.7 t 3.4 hurs. Administratin f the tablet results in a half-life f abut 6 t 12 hurs. The pharmaclgical actin f nifedipine persists fr up t 12 hurs after administratin f the tablet. Cautin shuld be used in patients with impaired liver functin. 3. Respnsibilities Obstetric medical staff are respnsible fr the medical management f wmen with acute hypertensin. This includes prescriptin f antihypertensive medicines as apprpriate t the wman, fr advising midwifery staff f the target bld pressure and ntificatin targets, fr review f the wman and planning n-ging care. Midwifery staff are respnsible fr the midwifery care f the wman. This includes determining accurate bld pressure management and accurate fluid balance management and fr escalating care t medical staff as directed. Bth clinical grups are respnsible fr being aware f the cntraindicatins, precautins and side effects f nifedipine, labetall and hydralazine and management f same. See ver the page fr the guideline details. Uncntrlled dcument when printed Publicatin date (16/05/2017) Page 1 f 10

2 4. Guideline Guideline Hypertensin - Management f Acute Fr all interhspital transfers W@S shuld cntact PERS (ph ). Clinical Practice Pints Hydralazine remains the drug f chice fr wmen with asthma r cngestive heart failure. Bld pressure readings must be manually recrded during the titratin phase. Bld Pressure recrding: The wman shuld be resting at an angle f greater than 45 degrees with her feet supprted. The bld pressure cuff shuld be f the apprpriate size and shuld be placed at the level f the heart. Standard cuff fr arms <33cm circumference. Large cuff (15x 33cm bladder) fr larger arms. Inflate cuff t 20-30mmHg abve palpated systlic pressure. Deflate slwly. Read and recrd bld pressure t nearest 2mmHg. Krtkff phase 5 sund (sund disappearance) is the apprpriate measurement f diastlic bld pressure. Multiple levels shuld be taken t cnfirm the diagnsis f hypertensin/ pre-eclampsia due t natural variatin. Autmated bld pressure readings may nly be cnsidered nce the maintenance dse has been achieved and the bld pressure is stable. Abrupt and prfund drps in bld pressure can ccur when vasdilatr therapy is nt accmpanied by vlume expansin in severe pre-eclampsia. This can lead t fetal bradycardia and nn-reassuring fetal status/ CTG patterns. Current literature suggests that there is n place fr blus fluid administratin prir t initiating acute antihypertensive treatment. In case f a severe hyptensive episde while infusin in prgress: cease infusin. place wman in the supine psitin, with her feet elevated and place a wedge under her right hip if undelivered (left tilt). seek urgent medical review. the infusin f plasma expanders may be required t reverse a nn-respnsive hyptensive episde. Cntinuus electrnic fetal mnitring is required fr all wmen underging IV antihypertensive management. Target bld pressure: Once the wman s BP has reached the target level then cmmence maintenance regimen aiming t maintain the systlic between and the diastlic BP at mmHg. There is rarely a need t lwer the BP further than this, and ding s may cmprmise the placental bld flw and fetus. 4.1 Nifedipine Initial management f acute hypertensin can include the use f ral immediate release nifedipine- nt slw release. Presentatin 10mg tablets. Cntraindictins Knwn hypersensitivity t nifedipine Uncntrlled dcument when printed Publicatin date (16/05/2017) Page 2 f 10

3 Hypertensin - Management f Acute Within the first eight days after an acute episde f mycardial infarctin Cncmitant administratin with rifampicin. Precautins Nifedipine may be used in cmbinatin with beta-blcking drugs and ther antihypertensive agents, but the pssibility f ptentiatin f existing antihypertensive therapy shuld be nted Impaired hepatic functin. Adverse effects Palpitatin, peripheral edema, vasdilatatin Nausea Dizziness. Administratin Administer 10mg nifedipine rally Mnitr the bld pressure Cmmence cntinuus CTG mnitring. A secnd dse may be administered minutes later if there is inadequate respnse. Observatins f mther and fetus shuld cntinue. If there is inadequate respnse after the secnd ral dse, prceed t IV management with an alternative antihypertensive. 4.2 Labetall A stat dse f 200mg labetall can be give rally. A secnd dse may be given rally if there is n respnse within 20 minutes. If bld pressure is still nt cntrlled, IV maintenance therapy shuld be cmmenced. Intravenus labetall is cnsidered t be the primary medicine f chice fr the urgent cntrl f severe hypertensin in pregnancy. It is assciated with a lwer incidence f adverse side effects and supplants the use f hydralazine. Usage will depend n availability and the clinicians experience and familiarity with the medicine. Please nte: IV labetall is a special access scheme (SAS) drug. A frm must be cmpleted fr each patient. These can be fund in the drug rm cupbard. Presentatin Labetall hydrchlride injectin is a sterile clear slutin cntaining 5mg/mL labetall hydrchlride (Each 20mL vial cntains 100mg labetall hydrchlride). Cntraindicatins Wmen with severe hypertensin and the fllwing cnditins must nt be administered labetall (hydralazine is the alternative treatment): asthma and allergic disrders with a predispsitin t brnchspasm. cngestive heart failure. hypvlaemic shck. Refer t the prduct infrmatin fr labetall - available at pi.pdf fr a full list f cntraindicatins. Precautins The wman shuld always be nursed in and remain supine (with lateral tilt) during and up t three hurs after IV administratin due t the ptential side effects f rthstatic hyptensin. Cnsider that recent administratin f ther antihypertensive drugs, such as nifedipine may ptentiate the bld pressure lwering effect f labetall. Refer t the prduct infrmatin fr labetall - available at Uncntrlled dcument when printed Publicatin date (16/05/2017) Page 3 f 10

4 Hypertensin - Management f Acute pi.pdf fr a full list f precautins. Cmpatibilities IMPORTANT: Refer t the Australian injectable drugs handbk (4 th editin) r cntact pharmacy fr drugs nt appearing in the table belw. Uncmmn drugs have simply been mitted and may be incmpatible. Fluids Cmpatible Sdium chlride 0.9% injectin Cmpund sdium lactate (Hartmann s) Glucse/sdium slutins Incmpatible Sdium bicarbnate 5% injectin Drugs N infrmatin Frusemide, ceftriaxne Y-Site Magnesium sulphate Adverse effects Pstural hyptensin may ccur if the initial dsage is t high r if the dse is increased t rapidly. Occasinally bradycardia and heart blck have been reprted. Transient dizziness, headache, tiredness, depressed md and lethargy may ccur. There have been reprts f a tingling sensatin f the skin (especially f the scalp) assciated with labetall treatment, usually ccurring early in treatment and is transient in nature. Refer t the prduct infrmatin fr a cmplete list f adverse effects available at: Administratin Labetall hydrchlride injectin is intended fr IV use in hspitalised patients. Labetall may be administered by IV infusin (refer t dses belw). Labetall IV blus A medical fficer must administer IV injectin dses f labetall: 20mg (4mL) administered by slw IV injectin ver tw (2) minutes. One further blus can be administered at 10 minutes if necessary. If 2 blus dses are insufficient t cntrl the bld pressure, IV therapy via infusin is required. Onset f actin f intravenus labetall is at five minutes. Peak effect ccurs at minutes. Duratin f actin is 45 minutes t six hurs.: Measure a bld pressure immediately befre, and at 5 and 10 minutes after administratin f each dse t evaluate the respnse. Cmmence an infusin f sdium chlride 0.9% r Hartmans slutin as a precautin measure t manage significant hyptensin. Cmmence cntinuus electrnic fetal mnitring. Labetall IV Infusin Wmen receiving IV infusin f labetall must be cared fr in an envirnment where ne-t-ne midwifery/nursing care can be facilitated (Birth Centre/ Cmplex Care). Prir t cmmencement the medical staff shuld explain t the wman the reasn fr administratin f the medicine, the cntinuus bservatin required and ptential adverse effects. Dsage must be individualised depending upn the severity f hypertensin and the respnse f the wman during dsing: Start the infusin at 20mg/hur. Uncntrlled dcument when printed Publicatin date (16/05/2017) Page 4 f 10

5 Hypertensin - Management f Acute Titrate the infusin t stabilize the bld pressure by adjusting the infusin by 5mg (2.5mL f the labetall infusin with a cncentratin f 2mg/mL). Nte that the maximum dse fr 24 hurs is 300mg. Measure a bld pressure immediately befre, and at 5 and 10 minutes after administratin f each dse t evaluate the respnse. Use a labetall slutin f 2mg/mL: T make this slutin: Use a 50mL syringe: draw up 20mL (100mg f labetall slutin). Further dilute this with 30mL sdium chlride 0.9% (using 3 ampules f 10mL) t make 50mL. The resultant slutin cntains 100mg labetall (2mg/mL). This slutin gives a final cncentratin f 2mg/mL (=100mg/ 50mL) Use 2 Additive Labels t clearly identify the additive. T ensure visibility, place ne label at eye-level and the ther at the prt int the multiflw adaptr. Management f a wman receiving labetall Unless therwise cntraindicated, the wman shuld receive 300mL f Sdium Chlride 0.9% as a fluid prelad ver 15 minutes. Nte: this prelad can be safely administered t thse wmen wh are fluid restricted. Administer thrugh a syringe infusin pump. Ensure all previus histry is deleted frm that pump. See Appendix Hw t set up the Pump. Administratin and Titratin Administer dse between mg/h. The rate f infusin is t be titrated by 20mg/h (10mL/h) every 15 minutes (this equates t titrating by 5mg (2.5mL) every 15 minutes f the labetall infusin with a cncentratin f 2mg/mL) until the bld pressure is stable. See Table 1 : Labetall dse titratin via infusin pump fr guidance. Cntinue with this titratin prcess until the maximum dsage f 160 mg/hr is reached OR the wman s bld pressure is maintained at / mmHg fr tw hurs. The infusin MUST be weaned dwn. This can be achieved by reducing the dse by 20mg (2.5mL) every 15 minutes prvided the bld pressure remains stable. The maximum dse f labetall t be infused is 300mg. Table 1. Labetall dse titratin via infusin pump fr guidance Labetall dse titratin via infusin pump: cncentratin=2mg/ml Time Span Infusin rate titratin Dse t be infused ver Time in mg (ml) Pump Vlume Pump Duratin set up Ttal mg administered ver time 0 minutes 20mg/hr (10mL/hr) 5mg (2.5mL) 15 minutes 5mg 15 minutes 40 mg/hr (20mL/hr) 10mg (5 ml) 15 minutes 15mg 30 minutes 60 mg/hr (30mL/hr) 15mg (7.5 ml) 15 minutes 30mg 45 minutes 80 mg/hr (40mL/hr) 20mg (10 ml) 15 minutes 50mg 60 minutes 100mg/hr (50mL/hr) 25mg (12.5 ml) 15 minutes 75mg 75 minutes 120 mg/hr (60mL/hr) 30mg (15 ml) 15 minutes 105mg 90 minutes 140 mg/hr (70mL/hr) 35mg (17.5 ml) 15 minutes 140mg 105 minutes 160 mg/hr (80mL/hr) 40mg (20 ml) 15 minutes 180mg 120 minutes Uncntrlled dcument when printed Publicatin date (16/05/2017) Page 5 f 10

6 Hypertensin - Management f Acute Nte: at maximum dse the wman has already received mre than half the 24 hur recmmended dse f 300mg. The time t wean ff the drug must als be cnsidered. The wman s respnse t the titratin must be reviewed at 1hur after cmmencement t determine the necessity t cntinue with this infusin r if a change in clinical management is required. Bld pressure shuld be mnitred during IV administratin. Titrate infusin and reduce bld pressure gradually t avid adverse fetal side effects frm a rapid decrease in uterplacental perfusin. Maintain cntinuus fetal mnitring f the viable fetus while endeavuring t ptimize bld pressure levels. Mnitring/bservatins Nte: Onset f actin f intravenus labetall is at five minutes. Peak effect ccurs at minutes. Duratin f actin is 45 minutes t six hurs. During titratin mnitr the bld pressure every 10 minutes, prir t each scheduled dse increase. The frequency f measurement is necessary t prevent sudden reductin in bld pressure that can affect placental perfusin. Cntinue until at least 2 stable cnsecutive readings are achieved. Once stable, bld pressure mnitring can be decreased t every half-hur. Additinal mnitring/bservatins (nce bld pressure stable): ½ hurly bld pressure, pulse, respiratry rate while infusin in prgress. 1 hurly urine utput measurement. 2 hurly temperature. 4 hurly testing f urinary prtein (full ward test). Cntinuus electrnic fetal mnitring: The viable fetus MUST be cntinuusly mnitred befre, during and after administratin f labetall. Weaning the labetall infusin: Labetall must nt be suddenly discntinued. It must be weaned ver 2 hurs. Decrease the infusin rate by 2.5mL/hr every 15 minutes. During weaning, bld pressure mnitring frequency must be increased t 15 minutely, prir t each reductin t ensure maintenance f bld pressure within target range. 4.3 Hydralazine Hydralazine is used fr the treatment f hypertensive crises - especially hypertensin assciated with pregnancy (pre-eclampsia r eclampsia). Presentatin Hydralazine ampules: 20mg dry pwder fr recnstitutin (white crystalline pwder). Cntraindicatins hypersensitivity t hydralazine. refer t full prduct infrmatin fr extensive list. Precautins cardiac dysfunctin. renal r hepatic impairment. cerebrvascular disease. refer t full prduct infrmatin fr extensive list. Cnsider that recent administratin f ther antihypertensive drugs, such as nifedipine may ptentiate the Uncntrlled dcument when printed Publicatin date (16/05/2017) Page 6 f 10

7 Hypertensin - Management f Acute bld pressure lwering effect f labetall. Cnsider that recent administratin f ther antihypertensive drugs, such as nifedipine may ptentiate the bld pressure lwering effect f Hydralazine. Incmpatibilities Refer t the Australian injectable drugs handbk (4 th editin) fr a full list f incmpatibilities r prduct infrmatin via MIMS nline. Adverse effects The fllwing symptms are cmmn at the start f treatment with hydralazine (especially if the dse is increased rapidly): tachycardia, palpitatin, anginal symptms, flushing, headache, dizziness, nasal cngestin and gastrintestinal disturbances. Such reactins generally subside with further curse f treatment. use f hydralazine can result in sdium and fluid retentin prducing edema and reduced urinary vlume. hydralazine is knwn t crss the placenta fllwing intravenus administratin and may be assciated with fetal distress and fetal cardiac arrhythmia in the last trimester f pregnancy. Refer t full prduct infrmatin fr extensive list. Nte: Reactive tachycardia with hydralazine may necessitate the use f beta-blckers. Occasinally hypertensin resistant t hydralazine requires administratin f ther medicines (e.g., nitrprusside, glyceryl trinitrate). Wmen receiving IV infusin hydralazine must be cared fr in an envirnment where ne-t-ne midwifery/nursing care can be facilitated (Birth Centre/Cmplex Care). Prir t cmmencement the medical staff shuld explain t the wman the reasn fr administratin f the medicine, the cntinuus bservatin required and ptential adverse effects. Dse Dsage must be individualized depending n the severity f hypertensin and the respnse f the wman during dsing: Start the infusin at 1mg/min fr 10 minutes. Titrate the infusin t stabilize the bld pressure by adjusting the infusin between 1-10mg/hr t maintain a diastlic BP f mmHg. Administratin Hydralazine injectin is intended fr IV use in hspitalized patients. Hydralazine may be administered by IV infusin (refer t dses belw). Ensure an intravenus main line f sdium chlride 0.9% x 1000mL (at 80mL/hr) is insitu via a multiflw adaptr prir t the administratin f hydralazine. Recnstitutin/ set up: Requires three (3) ampules f hydralazine 20mg pwder. Recnstitute each 20mg ampule pwder with 1mL f sterile water fr injectin until disslved. Prepare 2 syringes as fllws. These can be prepared at the same time. Administer thrugh a syringe infusin pump. Ensure all previus histry is deleted frm that pump. See Appendix Hw t set up the Pump. Syringe 1: lading dse (prescribed n ONCE ONLY sectin f medicines chart: Draw up 0.5mL (10mg) cncentrate int a 10mL syringe and make up t 10mL with sdium chlride 0.9% Label the syringe and cnnect t a minimum vlume extensin set Fllw the instructins f the Alaris GH syringe driver fr Hydralazine Lading Infusin. Uncntrlled dcument when printed Publicatin date (16/05/2017) Page 7 f 10

8 Hypertensin - Management f Acute Syringe 2: maintenance dse: Draw up 2.5mL (50mg) cncentrate int a 50mL syringe. Make up t 50mL with sdium chlride 0.9%. Label the syringe and cnnect t the Alaris GH Syringe drive fr Hydralazine Maintenance Infusin. This slutin gives a final cncentratin f 1mg/mL (= 50mg/50mL) Use 2 Additive Labels t clearly identify the additive. T ensure visibility, place ne label at eye-level and the ther at the prt int the multiflw adaptr. Dse: IV infusin Lading dse: Administer hydralazine at 1mg/min (i.e. 1mL/min f the prepared slutin) fr 10 minutes. Recrd bld pressure readings EVERY 5 MINUTES n the electrnic partgram during administratin f the intravenus lading infusin. If the bld pressure has reached the target range after 5 minutes administratin f the lading dse (i.e. 5mg), the lading dse may be ceased. Cmmence the maintenance dse. Maintenance infusin: Cntinue infusing hydralazine at 1-10mg/hr (1-10mL/hr) t maintain a diastlic BP f mmHg. Cntinue bservatin f BP every 15 minutes until stable and maintenance dse established. Maintain bservatin f BP every 30 minutes during administratin f the infusin. Mnitring/bservatins Initial mnitring/bservatins: Recrd bld pressure readings EVERY 5 MINUTES n the electrnic partgram during administratin f IV /lading dse. Cntinue bservatin f BP every 15 minutes until the BP is maintained at / mmHg fr tw hurs. The frequency f bld pressure mnitring can then be reduced t every 30 minutes fr the duratin f the infusin. The fetal heart rate is recrded every 10 minutes during the lading infusin. Other mnitring/bservatins: ½ hurly bld pressure, pulse, respiratry rate while infusin in prgress. 1 hurly urine utput measurement. 2 hurly temperature. 4 hurly testing f urinary prtein (full ward test). Cntinuus electrnic fetal mnitring: The viable fetus MUST be cntinuusly mnitred befre, during and after administratin f hydralazine. recrd n electrnic partgram and fluid balance chart. Discntinuatin f the infusin Hydralazine infusin des nt require weaning dwn and can be ceased as directed. The maximum dse f hydralazine shuld nt exceed 30 mg. Alternative antihypertensive management, such as nifedipine must be cnsidered be cnsidered if the BP is nt cntrlled nce this dse is reached. 5. Evaluatin, mnitring and reprting f cmpliance t this guideline Cmpliance t this guideline will be mnitred, evaluated and reprted by review f clinical incidents reprted Uncntrlled dcument when printed Publicatin date (16/05/2017) Page 8 f 10

9 Hypertensin - Management f Acute n VHIMS. 6. References 1. 3Centres Cllabratin Cnsensus Guideline Hypertensin in Pregnancy, Preeclampsia and Eclampsia. March Accessed: 22 April AHFS drug infrmatin McEvy GK, ed. Hydralazine. Bethesda, MD: American Sciety f Health- System Pharmacists; 2001: Magee LA, Helewa M, Mutquin JM, vn Dadelszen P. Diagnsis, Evaluatin, and Management f the Hypertensive Disrders f Pregnancy, Jurnal f Obstetrics and Gynaeclgy Canada, JOGC, n. 206, March MIMS Online Simple Search. Accessed 22 April Natinal Health Service (NHS), Greater Glasgw and Clyde, Queen Mther s Hspital. Guidelines fr the Management f Severe Hypertensin Phebra Prduct infrmatin. Labetall Hydrchlride Injectin. 7. Ryal Cllege f Obstetricians and Gynaeclgists (RCOG), The Management f Severe Pre- Eclampsia/Eclampsia (Green-tp 10A), March Sciety f Hspital Pharmacists f Australia (AIDH). Australian Injectable Drugs Handbk. 4 th Editin Suthern Health (Mnash Medical Centre). Preeclampsia and severe preeclampsia guideline. March Ryal Wmen s Hspital plicies, guidelines and prcedures: Pre-eclampsia: Management Magnesium Sulphate Management f Hypertensive Disrders f Pregnancy Eclampsia Management 7. Legislatin related t this guideline Nt applicable. 8. Appendices 1. Hw t set up the pump Uncntrlled dcument when printed Publicatin date (16/05/2017) Page 9 f 10

10 Hypertensin - Management f Acute 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 (16/05/2017) Page 10 f 10