Document ID: MATY077
Version: 1.0
Facilitated by: Eleanor Martin, Educator
Issue Date: November 2012
Approved by: Maternity Quality Committee
Review date: September 2018
Pre Eclampsia Policy
Purpose
The purpose of this guideline is to:• Establish a local approach to care, that is evidence based and consistent
• Inform good decision making
• Provide safe and effective care for women and their babies experiencing this
• condition
Scope
• All obstetric staff employed by the Hutt Valley DHB
• All midwifery staff employed by the Hutt Valley DHB
• All Hutt Valley DHB maternity access agreement holders.
• Anaesthetic staff
• Neonatal staff
Definition of Hypertension in Pregnancy
• Systolic blood pressure greater than or equal to 140 mmHg and/or
• Diastolic blood pressure greater than or equal to 90 mmHg (Korotkoff 5)
These measurements should be confirmed by repeated readings over several hours.
Elevations of both systolic and diastolic blood pressures have been associated with
adverse fetal outcome and therefore both are important.
There are several reasons to support the blood pressure readings above as
diagnostic of hypertension in pregnancy:
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Perinatal mortality rises with diastolic blood pressures above 90 mmHg
Readings above this level were beyond two standard deviations of mean
blood pressure in a New Zealand cohort of normal pregnant women
The chosen levels are consistent with international guidelines and correspond
with the current diagnosis of hypertension outside of pregnancy
Classification of Hypertensive disorders in pregnancy
Chronic Hypertension
Definition: Blood Pressure of 140mm Hg systolic and/or >90 mmHg diastolic
confirmed before pregnancy or before 20 completed weeks gestation without a
known cause. Some women may have a raised blood pressure in the presence of a
health professional but may be normotensive otherwise. These women however are
at increased risk of developing superimposed pre eclampsia.
Secondary causes of chronic hypertension include:
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Chronic Renal disease
Renal artery stenosis
Systemic disease
Endocrine disorders
Coarctation of the aorta
Pre-existing hypertension is a strong risk factor for the development for pre
eclampsia.
Gestational Hypertension
Definition: New onset of hypertension after 20 weeks gestation without any features
of Pre-eclampsia, followed by a return of blood pressure to normal within 3 months.
Pre eclampsia
Definition: New onset of hypertension after 20/40 returning to normal postpartum and
involvement of any one or more of the following systems (Steegers, von Dadelson,
Duvekot & Pijnenborg, 2010 & SOMANZ, 2008).
• Renal involvement
• Haematological
• Liver
• Neurological
• Pulmonary Oedema
• Fetal Growth Restriction
• Placental Abruption
• Proteinuria
Pre-eclampsia is a progressive disorder and delivery is the definitive management.
The leading hypothesis of the cause of pre-eclampsia is the disturbance of placental
function in early pregnancy (Steegers et al., 2010).
Pre-eclampsia is a major cause of maternal and infant morbidity. In New Zealand 8 –
10% of pregnancies will be affected by hypertension with 3 – 7% of pregnancies
complicated by pre-eclampsia. Many of the screening tests routinely performed in
pregnancy are aimed at the early detection of pre-eclampsia.
A collaborative approach involving the obstetrician, anaesthetist, paediatric RMO
and the midwife provides the best chance of a successful outcome. A plan of care is
required, individualised for each woman as there are many factors to consider e.g.
time of onset, severity of disease process and the unpredictability of the disorder.
Maternal effects
• Hypertension
• Proteinuria
• Acute renal failure
• Coagulopathy
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Haemolysis
Liver damage
Eclampsia
Stroke
Death
Fetal effects
• Small for gestational age (SGA)
• Prematurity
• Intra Uterine Growth Restriction
• Increased perinatal mortality
• Foetal compromise/foetal demise
First antenatal booking assessment
The following should be noted
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Primiparity
Multiple Pregnancy
Baseline blood pressure if > 140/90 or on hypertensive medication. See the
Guidelines for Consultation with Obstetric and Related Medical Services
(Referral Guidelines) MOH, 2012.
Baseline weight
Baseline height measurement
Calculation of BMI as BMI >35 is a risk factor
Age >40
Mid-stream urine sample
Maternal history of hypertension
Maternal history of pre-eclampsia in previous pregnancies with significant
IUGR or requiring delivery <34/40 or with multi organ involvement. See the
Guidelines for Consultation with Obstetric and Related Medical Services
(Referral Guidelines) MOH, 2012.
Family history of hypertension
Chronic kidney disease
Autoimmune disease systemic lupus erythematosis
Type 1 or 2 diabetic
Referral
Less than 12 weeks needs early referral to secondary care if any risk factors noted
at booking for Consultants decision on aspirin therapy (Bujold, Roberge et all.,
2010).
There are obviously many different scenarios for referral. Each is dependent on the
woman and her clinical situation. See the Guidelines for Consultation with Obstetric
and Related Medical Services (Referral Guidelines) MOH, 2012.
Care Planning
If risk factors exist and a referral is made then a care plan should be developed for
the woman and updated in a timely manner which indicates:
• Frequency of assessments
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Plan for further consultation
Who is responsible for care and or further assessments
Assessment
At each appointment after 20 weeks, it is essential that the LMC/care provider
identify signs and symptoms of the following:
• New hypertension
• New proteinuria
• Symptoms of headache or visual disturbance, or both
• Epigastric pain or vomiting or both
• Reduced fetal movements,
• Small for gestational age infant
Referral should then be made appropriately.
Women should be advised of the symptoms of pre-eclampsia and instructed to
contact their LMC/midwife or delivery suite. The person to contact should be
documented in the care plan.
Clinical Diagnosis
A clinical diagnosis of pre-eclampsia can be made when hypertension arises after 20
weeks gestation and the onset of one or more of the following occurs
• Urine creatinine/protein ratio ≥ 30mgs/mmol. Proteinuria ≥ 300 mg/24 hours
• Renal insufficiency; oliguria or serum/plasma creatinine ≥90 µmol/l
• Liver disease (impaired ALT/AST)
• Neurological involvement: convulsions (eclampsia), hyperreflexia with
sustained clonus; severe headaches, persistent visual disturbances
• Haematological disturbances: haemolysis, thrombocytopenia, disseminated
intravascular coagulation (DIC).
• Intrauterine growth restriction (IUGR)
• Placental abruption
• Pulmonary Oedema
Pre eclampsia can potentially fulminate so should not be taken lightly.
Transfer to a Tertiary Referral Centre
Women with preeclampsia between the gestational ages of 24-32 weeks are
transferred to the Tertiary care facility at the discretion of the consultant obstetrician.
Indications for Delivery
• Inability to control hypertension
• Deteriorating platelet function, liver and renal function
• Placenta Abruptio
• Persistent neurological symptoms
• Eclampsia
• Epigastric pain, nausea and vomiting
• Acute pulmonary oedema
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Medical Management of Hypertension
Drug
Labetalol
Dose
100-400mgs
three
times/day
Action
ß Blocker
with mild
alpha
vasodilator
effect
Central
MethylDopa
270-750mgs
Three
times/day
Nifedipine
20-60mgs
twice/day
Ca Channel
antagonist
Hydralazine 25-50mgs
Three
times/day
Vasodilator
Contraindications
Practice Points
Asthma
Bradycardia,
bronchospasm,
headache,
nausea, scalp
tingling
Depression
Slow onset over 24
hours. Dry mouth,
sedation,
depression,
blurred vision
Aortic Stenosis
Severe headache,
associated with
flushing,
tachycardia,
peripheral oedema,
constipation
Flushing, headache,
nausea, lupus like
syndrome
Antihypertensive treatment should be commenced on all women with a systolic BP ≥
170mm Hg or diastolic BP ≥ 110mmHg because of the risk of intracerebral
haemorrhage and eclampsia.
Intravenous hydralazine, intravenous labetalol and oral nifedipine may all be used in
pregnancy for the acute treatment of severe hypertension. Although smaller studies
have shown a trend towards maternal hypotension with associated risk of abruption,
caesarean section and decreased apgars with the use of IV hydralazine, no definitive
evidence exists that one agent is superior to another (Duly, Henderson- Smart &
Meher, 2006). The obstetric consultant is responsible for the on-going management
of the woman.
Prevention of convulsions and control of acute convulsions
Magnesium sulphate has been shown in randomised trials to be the medication of
choice in the prevention of convulsions.
Administration of magnesium sulphate is a two-stage process:
1. Administration of a bolus dose
2. Maintenance infusion (see Appendix1)
Practitioners are also referred to the Acute management of eclampsia policy for
treatment of acute convulsions
Expectant management versus the decision to deliver the woman
The management plan for the woman is a decision made by the consultant in
conjunction with the woman. This depends on many factors but must include:
• Foetal gestation
• Foetal status
• Severity of maternal condition
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Appendix II presents a possible management algorithm for women. When expectant
management is practised, close monitoring of the woman and her baby is
mandatory.
Antenatal Monitoring and care of a woman with pre-eclampsia
Care of the woman in the antenatal period depends on whether she is admitted to
the hospital for care, observation or delivery.
Assessment and care of the woman as a day case is covered in the MAU Antenatal
day case monitoring for women with pre-eclampsia policy
Monitoring of the woman admitted to the maternity unit.
Recommend birth for women who have pre-eclampsia with severe hypertension after
34 weeks when their blood pressure has been controlled and a course of
corticosteroids has been completed (if appropriate).
Offer birth to women who have pre-eclampsia with mild or moderate hypertension at
34+0 to 36+6 weeks depending on maternal and fetal condition, risk factors and
availability of neonatal intensive care.
Recommend birth within 24–48 hours for women who have pre-eclampsia with mild
or moderate hypertension after 37+0 weeks. (NICE, 2011). ©
Aim: Ensure safety of mother and baby, while monitoring to detect any worsening of
pre-eclampsia.
Maternal Observations
• BP taken 4 hourly over 24 hours (See Guidelines for blood pressure
measurement in pregnancy, labour and the postnatal period).
• Using appropriate equipment
• Diastolic taken as 5th Korotkoff sound
• Recorded on antegram plus individual care plan initiated
• Any abnormal findings/worsening should be repeated and the obstetric team
notified
Blood pressure medication
• Administered as prescribed
Urinalysis
• Daily monitoring of urine output i.e. volume and amount of protein should be
noted.
• A mid-stream urine should be sent for urinalysis and microscopy on admission
• Urine for PCR taken and sent as appropriate
• 24hr collection of Urine for protein estimation
Laboratory blood testing should include
• Haemoglobin, haematocrit, platelet count also to be available prior to epidural.
• Coagulation studies if there is evidence of thrombocytopenia or haemolysis
• Serum uric acid
• Serum creatinine
• Liver function tests
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Maternal observations
• Fluid balance: It is advised that an accurate fluid balance record is maintained
for the woman.
• Observations for signs of convulsions: ie hyper reflexia with clonus.
• If planning for elective birth by either induction or Caesarean section steroid
therapy should be considered before 37 weeks.
Fetal Assessments
• Maternal Pulse is taken and documented on the CTG trace.
• The frequency of EFM is documented in the care plan
• Midwife to remain with the woman during the trace
• Discontinued when classified as normal or if abnormal consult appropriately
• Notation on elements of the recording included in the clinical notes
Ultrasound scanning for growth parameters and Doppler studies
Management of Severe Pre-eclampsia
Admit the woman to delivery suite for one to one midwifery care.
Referral to team
• Obstetric consultant and registrar (as per section 88)
Observations
• All observations recorded on a specialised chart MEWS
• Oxygen saturation should be continuously monitored
• Blood pressure recordings as clinically indicated. The preferred equipment is
the aneroid sphygmomanometer.
Electronic blood pressure equipment should not be used for women with
preeclampsia as they under record readings for women with pre-eclampsia.
(Reinders et al, 2003, p.134.)
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Pulse and respirations taken as clinically indicated
Continuous electronic foetal monitoring
Investigations
• Blood tests
• Urinalysis
Medications
• To prevent eclampsia: Magnesium sulphate bolus and infusion
• To reduce hypertension to maintain at 140/90
• Consider corticosteroids for foetal lung maturation
Intrapartum Care
• Care of the woman should continue as above with intensive monitoring of the
woman and her baby. Electronic foetal monitoring is continuous while the
woman is in labour.
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The woman’s progress in labour is documented on a partogram and continue
with MEWS
Maintain intravenous fluids at 80 mls/hr (1ml/kg)
Insert an indwelling catheter. Measure urine hourly output, ought to be
maintained at 0.5 mls/kg/hour. If it is less than 0.25 mls/kg/hour for more than
2 hours notify the obstetrician on call.
No fluid boluses unless decided by consultant
A detailed plan of care should be documented in the woman’s notes with
responsibilities clearly identified
Hypertension should be managed as per obstetrician instructions with the
blood pressure parameters 140/90 being seen as a reasonable target
Monitor blood pressure as clinically indicated, may even be every five minutes
if the woman has an unstable blood pressure.
Syntocinon is the ecbolic of choice either 5 international units intravenously or
10 international units intramuscularly. Women with pre-eclampsia should
never receive ergometrine either by itself or in Syntometrine (Brown, 2000, p.
148).
The paediatric RMO should be present for the delivery.
The timing and type of intrapartum analgesia should be discussed in
conjunction with the obstetrician. This decision will take into account the
woman’s clotting status
Postpartum Management
Pre-eclampsia is generally resolved by the delivery of the placenta; however there
are a small number of women for whom the condition can worsen. Women should be
educated about the signs and symptoms of pre-eclampsia and advised to contact
their midwife or LMC if they notice any signs.
A multi-disciplinary approach to the woman’s care in the postnatal period is required.
Factors that should be taken into consideration include:
• Severity of the woman’s pre-eclampsia
• The best place to care for the woman and her baby in the postpartum period
(Initially delivery suite or ICU)
• Ongoing monitoring
monitoring of fluid balance
Blood pressure recordings must continue even when the woman is
transferred to the postnatal ward and to the community
Routine postnatal care of the woman
Early involvement of GP
• Lab tests should be also be repeated in the postpartum period
• Women should be educated on the signs and symptoms of pre-eclampsia
• Women who report persistent severe headaches, visual changes, Epigastric
pain with nausea or vomiting, or respiratory symptoms need immediate
assessment and potential hospital care.
• A full and open discussion can occur whenever the woman and her partner
are ready – even at the six week postnatal clinic appointment.
(Sibai, 2005, p.796)
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Associated documents
Guidelines for blood pressure measurement in pregnancy, labour and the postnatal
period.
Acute management of eclampsia
Protocol: Administration of magnesium sulphate for prevention and treatment of
eclampsia (includes the administration of calcium gluconate)
MAU Antenatal day case monitoring for women with pre-eclampsia
Intravenous hydralazine policy
Intravenous Labetalol policy
References
Abalos, E., Duley, L., Steyn, DW & Henderson – Smart, DJ. (2001). Antihypertensive drug therapy for
mild to moderate hypertension during pregnancy. Cochrane database of systematic reviews, June
2005.
Bewley, C. (2004). Hypertensive disorders of pregnancy. In Henderson, C. & MacDonald, S. eds.
Mayes Midwifery 13th ed. Edinburgh: Balliere Tindall.
Brown, M.A., Hague, W.M., Higgins, J., Lowe, S., McCowan, L., Oats, J., Peek, M.J., Rowan, J.A. &
Walters, B.N.J. (2000). The detection, investigation and management of hypertension in pregnancy:
full consensus statement. Australian New Zealand
Journal of Obstetrics and Gynaecology, 40, 139 – 155. Bujold,E., Roberge, S., Lacasse, Y., Bureau,
M., Audibert,F. Marcoux, S., Forest,J. & Giguere (2010). Prevention of Preeclampsia and Intrauterine
Growth Restriction With Asprin Started in Early Pregnancy. Obstetrics & Gynaecology, 116,402-414
Chan, P., Brown, M., Simpson, J., & Davis, G. (2005). Proteinuria in pre-eclampsia: how much
matters. BJOG, 112, 280 – 285. Churchill, D. & Duley, L. (2005). Interventionalist versus expectant
care for severe pre-eclampsia before term. The Cochrane Database of Systematic reviews, June
2005.
Drife, & Lewis, (2002). Why mothers die? Confidential enquiries into maternal deaths. London:
RCOG.
Duckitt, K. & Harrington, D. (2005). Risk factors for pre-eclampsia at antenatal booking; systematic
review of controlled studies. BMJ, 330, 565-567
Duley, L., Gulmezoglu, A.M. & Henderson-Smart, D.J. (2005). Magnesium sulphate and other anticonvulsants for women with pre-eclampsia. Cochrane Database of Systematic Reviews. August 2005.
Duley, L., Williams, J. & Henderson-Smart, D.J. (2004). Plasma volume expansion
for treatment of pre-eclampsia. Cochrane Database of Systematic reviews: June
2005.
Duley, L., Henderson-Smart, D.J. & Meher. (2006). Drugs for treatment of very high blood pressure
during pregnancy. Cochrane data base systematic reviews: CD001449
Foy, R., Ramsay, C., Grimshaw, J., Penney, G., Vale,L., Thomson, A. & Greer, I. (2004). The impact
of guidelines on mild hypertension in pregnancy: time series analysis. BJOG, 111, 765 – 770.
Jordan, S. Cardiovascular Disorders in pregnancy. In Jordon, S. (ed). (2002). Pharmcology for
midwives. UK: Palgrave.
Maresh, M., James, D. & Neales, K. Critical care of the obstetric patient. In James, D.K., Steer, P.J.,
Weiner, C.P. & Gonik, B. (2000). High risk pregnancy: Management options 2nd ed. London: W.B
Saunders. Magee, L. & Sadeghi, S. (2004). Prevention and treatment of postpartum hypertension.
The Cochrane Database of Systematic reviews, last accessed June 2005.
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Magpie Trial Collaborative Group. (2002). Do women with pre-eclampsia and their babies, benefit
from magnesium sulphate? The Magpie Trial: A randomised placebo controlled trial. The Lancet, 359,
1877 – 1890.
Milne, F. et al, (2005). The pre-eclampsia community guideline (PRECOG): how to screen for and
detect onset of pre-eclampsia in the community. BMJ, 330, 576 – 580.
Ministry of Health.(2012) Guidelines for Consultation with Obstetric and Related Medical Services
(Referral Guidelines). Wellington: Ministry of Health
National High Blood pressure Education Programme Working group on High Blood Pressure in
Pregnancy. (2000). Report of the National High Blood pressure education programme working group
on high blood pressure in pregnancy. American Journal of Obstetrics and Gynaecology, 183, S1-S22.
NICE Guidelines, (2011) Hypertension in Pregnancy Guideline No 107, retrieved from:
guidance.nice.org.uk/cg107.
North, R. (2005). Pre-eclampsia. Presentation made at the APEC study day. Lower Hutt: June 2005.
NZAPEC Why blood pressure is checked in pregnancy. Auckland: NZAPEC
NZAPEC. Testing the water. Auckland: NZAPEC Reinders, A., Cuckson, A.C., Jones, C. R., Poet, R.,
O;Sullivan, G. & Shennan,A. (2003). Validation of the Welch Allyn Vital Signs blood pressure
measurement device in pregnancy and pre-eclampsia. BJOG, 110, pp 134 –138
Reinders,A., cuckson, A.C., Lee, J.T.m. & Shennan, A. (2005). An accurate blood pressure device for
use in pregnancy and pre-eclampsia: the Microlife 3BTO-A. BJOG, 112, 915 – 920.
Sibai, B., Dekker, G. & Kupferminc, M. (2005). Pre-eclampsia. The Lancet, 365, 785
– 799.
Sibai, B. (2003). Diagnosis and management of gestational hypertension and preeclampsia.
American Journal of Obstetrics and Gynaecology, 102, 181 – 192
Sibai, B. (2004). Magnesium sulfate prophylaxis in pre-eclampsia: Lessons learned from recent trials.
American Journal of Obstetrics and Gynaecology, 190, 1520 – 1526.
Scottish Obstetric Guidelines & Audit Project, (1997). The management of mild nonproteuniuric
hypertension in pregnancy. www.sign.co.uk/guidelines. Last accessed July 2005.
Wagner, L. K. (2004. Diagnosis and management of pre-eclampsia. American Family Physician, 70,
2317 – 2324.
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Appendix I
Magnesium Sulphate Protocol
Purpose
The purpose of this guideline is to:
• establish a local approach to care that is evidence based and consistent
• inform decision making
• provide safe and effective care for women and their babies
SCOPE
All obstetric staff employed by the Hutt Valley DHB
All midwifery staff employed by the Hutt Valley DHB
All Hutt Valley DHB maternity access agreement holders.
Anaesthetic staff
Neonatal staff
Indications for use of magnesium sulphate
• women when experiencing a fulminating pre-eclampsia
• foetal neuro-protection for babies under 30 weeks in consultation with Paediatric
SMO
Administration of Magnesium Sulphate
The woman is assessed by the Obstetric Team. The registrar must consult with the
Obstetric SMO (and paediatric SMO as appropriate) prior to the prescription of
magnesium sulphate therapy.
The obstetric specialist/registrar must be in birthing suite while the loading
dose is being administered.
Equipment
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6 ampoules of Magnesium sulphate (2.47g of Magnesium sulphate in each 5 ml,
(contains 10mmol magnesium and 10mmol sulphate ions)
2 x 100 ml bag of 0.9% sodium chloride
1000 ml 0.9% sodium chloride
20 ml syringe
10 ml syringe
Drawing up needles
2 intravenous giving sets
1 ‘Y’ extension set leur-lock with back check valves
Calcium gluconate (antidote for magnesium sulphate)
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Loading Dose:
A loading dose of 4 grams is administered intravenously over 20 minutes.
Prescription
• 4g MgSO4 in 8mls added to 100ml of 0.9% sodium chloride.
• Total volume 108ml.
• Administer over 20 minutes.
Procedure
• In a 10cc syringe draw up 8ml of MgSO4. Add to a 100ml bag of 0.9% sodium
chloride.
• Total volume = 108ml.
• Administer over 20 minutes via an electronic infusion device.
• Rate of 324mls/hour.
• Rate checked by 2 staff members prior to commencing infusion.
Warn the woman of the burning/flushing effect she may feel. The midwife must stay
with the woman while the loading dose is being administered.
Maternal observations during the loading dose.
• Pulse (P), Blood pressure (BP), Respirations (RR), Continuous Oxygen SATS,
reflexes.
• Frequency every 5 minutes.
Foetal observations
• Continuous electronic foetal monitoring until the baby has birthed.
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Continuous Infusion:
The loading dose is followed by a continuous infusion of 1 gram of MgSO4 per hour.
Prescription
• 8g MgSO4 in 16mls added to 100ml of 0.9% sodium chloride.
• Total volume = 116mls.
• Administer over 8 hours via an electronic infusion device = 1g MgSO4 / hour.
Procedure
• In a 20cc syringe draw up 16mls MgSO4. Add to a 100ml bag of 0.9% sodium
chloride.
• Total volume = 116mls
• Commence a mainline infusion of 1000ml 0.9% sodium chloride at rate as
directed by obstetric SMO. Add the Y connector with back check valve to the
tubing. Connect the MgSO4 to the second arm of the Y connection.
• Administer MgSO4 over 8 hours via an electronic infusion device.
• Rate of 14.5 mls/hour.
• Rate checked by 2 staff members prior to commencing infusion.
• The infusion is continued for minimum 24 hours after birth or the last seizure and
then discontinued. Note: This will require a minimum of 3 infusions of 8g
MgSO4 in 100ml of 0.9% sodium chloride.
Maternal Observations
Clinical
• Commence ¼ hourly observations of the following:
o Respirations, Pulse, Blood Pressure by a manual BP machine ,
o Patellar reflexes
o Level of consciousness,
o Oxygen saturations
• Observations can change to hourly when the woman has stabilised.
Foetal Observations
Continuous electronic foetal monitoring until the baby is delivered.
Serum Magnesium levels
The above regime of Magnesium Sulphate does not require testing of blood
concentration because clinical effect can be monitored by deep tendon reflex.
(Steegers, E.a.P., von Dadelszen,P., et al, 2010) unless requested by medical staff.
In women with renal compromise, serum magnesium monitoring is recommended
(The Antenatal Magnesium Sulphate for Neuroprotection Guideline Development
Panel, 2010).
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Take 1 hour after commencement of loading dose
Repeat at regular intervals (4 hourly) while infusion is running
Repeat urgently if the woman exhibits signs of toxicity
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Magnesium levels and symptoms
Normal range
Therapeutic range
Loss of patellar reflex
Somnolence
Respiratory depression
Paralysis
Cardiac arrest
Range in (mmol /litre)2
0.5 – 1.1
2–4
>5
>5
>6
>7
> 12
(Reference Fontaine and Sabourin, 2005, B6)
Discontinuing the Infusion
The infusion should be maintained for at least 24 hours after the last seizure or after
birth of the baby.
The administration rate may need to be reduced under the advice of the obstetric
Consultant if the following effects are noted
• Decreased O2 saturations
• Depressed respiration rate <12/min/
• Hypotension diastolic <80 mmHg
• Tachycardia >120/min
Immediate action is required in the event of Magnesium toxicity:
Magnesium sulphate toxicity leads to
• Loss of deep tendon reflexes
• Muscle paralysis
• Respiratory arrest
• Cardiac arrest
• Death
Signs of toxicity include:
• Flushing of face
• Loss of patella reflexes
• Weakness
• Nausea
• Sleepiness
• Double vision
• Blurred vision
In the event of above, stop magnesium sulphate and Call 777 and state
‘maternal arrest’
START Basic life support
Prepare 1 gram calcium gluconate IV (10 mls of a 10% solution)
over 10 minutes to be given as directed by SMO Obstetrician
The SMO Obstetrician / SMO Anaesthetist will make the decision for on-going
management and physical transfer of mother.
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An anti-convulsant may be used at the discretion of a consultant. Caution must
be used when administering such medications as they may lead to respiratory
depression, aspiration and cardiac arrest especially when used in conjunction with
magnesium sulphate.
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Appendix II
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