Introduction Hypertension is one of the most common complication during pregnancy Increased maternal and perinatal morbidity and mortality It is a sign of an underlying pathology that may be pre- existing or appears for the first time during pregnancy that is why it is also called asTOXEMIA OF PREGNANCY Journals of the American college of obstetricians and gynecologists Module of dr. Ayeshwara Ravindra Kaur ASH position article Hypertension Blood pressure of 140/90 mmHg or more or an increase of 30 mmHg in systolic and/or 15 mmHg in diastolic blood pressure over the pre- or early pregnancy level. DC Dutta`s textbook of obstetrics 8th edition, p- 255 Incidence 6% to 8% of all the pregnancies Complicates 10-20% of pregnancies District I ACOG Medical Student Education Module 2011 Prevalence Hypertensive disorders during pregnancy occur in women with preexisting primary or secondary chronic hypertension, and in women who develop new-onset hypertension in the second half of pregnancy The present study was undertaken to study the prevalence and correlates of hypertension in pregnancy in a rural area • A total of 931 pregnant women were included in the present study. Prevalence of hypertension in pregnancy was found to be 6.9%. Maternal age ≥25 years, gestational period ≤20 weeks, history of cesarean section, history of preterm delivery, and history of hypertension in previous pregnancy were found to be significantly associated with prevalence of hypertension in pregnancy Risk Factors for Hypertension in Pregnancy Nulliparity Pre-eclampsia in a previous pregnancy Age >40 years or <18 years Family history of pregnancy-induced hypertension Chronic hypertension Chronic renal disease Anti-phospholipid antibody syndrome or inherited thrombophilia DC Dutta`s textbook of obstetrics 8th edition, p- 256 Vascular or connective tissue disease Diabetes mellitus (pre-gestational and gestational) Multi-fetal gestation High body mass index Male partner whose previous partner had preeclampsia Hydrops-fetalis
Unexplained fetal growth restriction Risk Factors for Hypertension in Pregnancy (cont.) DC Dutta`s textbook of obstetrics 8th edition, p- 256 Classification of Pregnancy induced hypertension According to national high blood pressure education program 2000 and ACOG-2013 1. Chronic hypertension 2. Pre-eclampsia 3. Chronic hypertension with superimposed pre-eclampsia and eclampsia 4. Gestational Hypertension 5.Transient Hypertension The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation andTreatment of High Blood Pressure DC Dutta`s textbook of obstetrics 8th edition, p- 255 6. HELLP syndrome- a. Hemolysis (H) b. Elevated liver enzymes (EL) c. Low platelet count (LP) 7. Eclampsia 8. Superimposed pre-eclampsia or eclampsia 9. Proteinuria The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation andTreatment of High Blood Pressure DC Dutta`s textbook of obstetrics 8th edition, p-255 Chronic hypertension in pregnancy The presence of hypertension of any cause antedating or before the 20th week of pregnancy beyond the 12 weeks after delivery Women with CH are low risk and have satisfactory maternal and fetal outcome without any hypertensive therapy by life-style modification With life-style modification, aerobic exercise should be restricted based on theoretical concerns. Risk factors: Age (>40 years) Duration of hypertension (>15 years) Level of BP (>160/110 mm of Hg) Presence of any medical disorder Presence of thrombophilias The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation andTreatment of High Blood Pressure DC Dutta`s textbook of obstetrics 8th edition, p- 277 Effect of Chronic Hypertension on Pregnancy Maternal: superimposed pre-eclampsia/ eclampsia in 15-20% of cases Foetal: Intrauterine growth retardation. Intrauterine foetal death. module of dapinderjit gill, rose university Prenatal Care for Chronic Hypertensives
Electrocardiogram should be obtained in women with long- standing hypertension. Baseline laboratory tests Urinalysis, urine culture, and serum creatinine, glucose, and electrolytes Tests will rule out renal disease, and identify comorbidities such as diabetes mellitus. Women with proteinuria on a urine dipstick should have a quantitative test for urine protein The American college of obstetricians and gynocolists Treatment General and medical treatment As pre-eclampsia regarding the following: Rest Antihypertensives Observation DC Dutta`s textbook of obstetrics 8th edition, p- 277 The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation andTreatment of High Blood Pressure Pre-eclampsia Definition It is a multisystem disorder of unknown etiology characterized by development of hypertension to the extent of 140/90 mm of Hg or more with proteinuria after the 20th week in a previously normotensive and non-proteinuric women DC Dutta`s textbook of obstetrics 8th edition, p- 256 Incidence: In hospital: varies widely from 5% to 15% The incidence in primi-gravidae is about 10% and in multi-gravidae is 5% More common in women with chronic hypertension, with an incidence of approximately 25% DC Dutta`s textbook of obstetrics 8th edition,p-256 The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation andTreatment of High Blood Pressure Pre-disposing factors Primigravidae more than multi-gravidae. Pre-existing hypertension. Previous pre-eclampsia. Family history of pre-eclampsia. Hyperplacentosis i.e. excessive chorionic tissue as in hydatidiform mole, multiple pregnancy, uncontrolled diabetes mellitus and foetal haemolytic diseases. Obesity.
New paternity Thrombophilias DC Dutta`s textbook of obstetrics 8th edition.p-256 Pathophysiology The uteroplacental bed Immunological factor Genetic factor Renin- angiotensin system Atrial natriuretic peptide (ANP) Prostaglandins Neutrophils DC Dutta`s textbook of obstetrics 8th edition,p-258 Diagnostic criteria: - Hypertension - Edema - Proteinuria Categories Mild Preeclampsia Severe Preeclampsia DC Dutta`s textbook of obstetrics 8th edition,p-258 Clinical features: Symptoms: Mild: slight swelling over the ankle Gradually swelling may be extend to the face, abdominal wall, vulva even the whole body. Alarming: Headache Disturbed sleep Diminished urinary output Epigastric pain Eye symptoms- blurring, scotomata, dimness of vision or at times complete blindness. Vision usually regained within 46 weeks following delivery. DC Dutta`s textbook of obstetrics 8th edition, p-261 Signs: Abnormal weight gain Rise of blood pressure Edema There is no manifestation of chronic cardiovascular or renal pathology Pulmonary edema
Abdominal examination my reveal evidences of chronic placental insufficiency such as scanty liquor or growth retardation of the fetus DC Dutta`s textbook of obstetrics 8th edition,p-261 Investigations: Urine: 24 hours urine collection for protein measurement is done. Urine become solid on boiling (10-15 g/L) A few hyaline cast, epithelial cells or few red cells. Ophthalmoscopic examinations: In severe cases- retinal edema, constriction of arterioles, alteration of normal ration of vein, nicking the veins, hemorrhage. DC Dutta`s textbook of obstetrics 8th edition,p-262 Blood values: Serum uric acid level >4.5 mg/dl indicates presences of pre-eclampsia Blood urea level remains normal Abnormal coagulation profile Raised hepatic enzyme levels Antenatal fetal monitoring: Done by clinical examination Daily fetal kick count USG of fetal growth Liqour pockets Cardiotocography Umbilical artery flow velocimetry Bio-physical profile DC Dutta`s textbook of obstetrics 8th edition,p-262 Complications Immediate: Maternal: During prengnancy: a. Eclampsia (2%) b. Accidental hemorrhage c. Oliguria and anuria d. Dimness of vision even blindness e. Pre-term labour f. HELLP syndrome g. Cerebral hemorrhage h. Acute respiratoy distress syndrome (ARDS) During labour: a. Eclampsia b. Post partum hemorrhage (PPH) Puerperium: a. Eclampsia b. Shock c. Sepsis DC Dutta`s textbook of obstetrics 8th edition,p-263 Fetal: a. Intrauterine death (IUD) b. Intrauterine growth retardation (IUGR) c. Asphyxia d. prematurity Remote: a. Residual hypertension b. Recurrent pre-eclampsia c. Chronic renal disease d. Risk of placental abruption DC Dutta`s textbook of obstetrics 8th edition,p-263
Prediction No screening test is really helpful Various screening methods are: Diastolic notch at 24weeks by Doppler ultrasonography Absence or reversal of end diastolic flow Average mean arterial pressure ≥ 90 mmHg in second trimester Infusion test: angiotensin infusion required to raise the blood pressure >20 mm Hg from baseline Roll over test: Rise in blood pressure >20 mmHg from baseline on turning supine at 28-32 weeks gestation is positive DC Dutta`s textbook of obstetrics 8th edition,p-263
Pre-eclampsia management General measures: Maternal Blood pressure twice daily Urine volume and proteinuria daily Oedema daily Body weight twice weekly Fundus oculi once weekly Blood picture including platelet count, liver and renal functions particularly serum uric acid on admission Daily foetal movement count Serial sonography Non-stress and stress test if needed Observation Fetal DC Dutta`s textbook of obstetrics 8th edition,p-265 Medical treatment Antihypertensives: Decrease the maternal cerebral and cardiovascular complications but do not affect the foetal outcome Alpha-methyl-dopa: It reduces the central sympathetic drive Dose: 250-500 mg every 6-8 hours up to a maximum dose of 4 gm/day. Its effect appears after 48 hours A loading single dose of 2 gm may act within 1-2 hours Side effects: headache, athenia and nightmares DC Dutta`s textbook of obstetrics 8th edition,p-265
Medical treatment (cont.) Hydralazine: It is a vasodilator, increases renal and uteroplacental blood flow Dose: 20 mg slowly IV initially followed by 5mg every 20 min. until diastolic blood pressure is 100-110 mmHg.This regimen is used for severe and acute hypertension. Oral hydralazine can be used in the chronic situation as a second line treatment in a dose of 25-75 mg/ 6 hours Side effects: tachycardia, headache, flushing, nausea and vomiting Calcium channel blockers (Nifedipine): It is a vasodilator acting by blocking the Ca influx into smooth muscle cells It can be given sublingually (acts within 10 minutes) or orally (acts within 30 minutes) in a dose of 10-20 mg 2-3 times daily The higher the starting blood pressure the greater is the hypotensive effect. Side effects: headache and flushing DC Dutta`s textbook of obstetrics 8th edition,p-265 The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation andTreatment of High Blood Pressure Prophylactic Proper antenatal care: To detect the high risk patients who may develop PIH through the screening tests Early detection of cases who have already developed PIH and examine them more frequently Low dose aspirin: It inhibits thromboxane production from the platelets and the AII binding sites on platelets A low dose (60 mg daily) selectively inhibits thromboxane due to higher concentration of such a low dose in the portal circulation than systemic affecting the platelets when they pass through the portal circulation.The Prostacyclin production from the systemic vessels will not be affected DC Dutta`s textbook of obstetrics 8th edition,p-265-66 Curative Delivery of the foetus and placenta is the only real treatment of pre- eclampsia. As the conditions are not always suitable for this, the treatment aims to prevent or minimize the maternal and foetal complications till reasonable maturation of the foetus. DC Dutta`s textbook of obstetrics 8th edition,p-265-66 Obstetric measures Timing of delivery Method of delivery Intrapartum care
Postpartum care DC Dutta`s textbook of obstetrics 8th edition,p-267 Obstetric measures Timing of delivery: Severe pre-eclampsia is usually treated conservatively till the end of the 36th week to ensure reasonable maturation of the foetus. Indications of termination before 36th week include: 1. Aggravation of pre-eclamptic features 2. Hypertension persists 3. Acute fulminating pre-eclampsia 4. Tendency of pregnancy to overrum the expected date DC Dutta`s textbook of obstetrics 8th edition,p-266-67 Method of delivery Vaginal delivery may be commenced in vertex presentation by: Amniotomy + oxytocin if the cervix is favorable Prostaglandin vaginal tablet (PGE2) if the cervix is not favorable Caesarean section is indicated in: Foetal distress Late deceleration occurs with oxytocin challenge test Failure of induction of labour Other indications as contracted pelvis, and malpresentations DC Dutta`s textbook of obstetrics 8th edition,p-266-67 Intrapartum care Close monitoring of the foetus is indicated Proper analgesia to the mother Anti-hypertensives may be given if needed 2nd stage of labour may be shortened by forceps DC Dutta`s textbook of obstetrics 8th edition,p-266-67 Postpartum care Methergin (Ergometrine) is better avoided as it may increase the blood pressure Continue observation of the mother for 48 hours Anti- hypertensive drugs are continued in a decreasing dose for 48 hours DC Dutta`s textbook of obstetrics 8th edition,p-266-67 Prevention of preeclampsia • Identification of high-risk women • Close clinical and laboratory monitoring aimed at its early recognition • Institution of intensive monitoring or delivery when indicated. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation andTreatment of High Blood Pressure
Note Imminent eclampsia: It is a state in which the patient is about to develop eclampsia. Usually there are: Blood pressure much higher than 160 /110 mmHg Heavy proteinuria (+++or ++++) Hyperreflexia Severe continuous headache Blurring of vision Epigastric pain Fulminating pre-eclampsia: a rapidly deteriorating pre-eclampsia to be imminent eclampsia DC Dutta`s textbook of obstetrics 8th edition, p-267 Chronic hypertension with superimposed pre-eclampsia or eclampsia The common cause of chronic hypertension: - Essential hypertension - Chronic renal disease - Coarctation of aorta Endocrine disorders (DM, pheochromocytoma, thyrotoxicosis) - Connective tissue disease (SLE) Criteria for diagnosis of superimposed pre-eclampsia: - New onset of proteinuria >0.5 g/24 hours specimen Aggravation of hypertension - Development of HELLP syndrome - Development of headache scotoma, epigastric pain The American college of obstetricians and gynocolists Gestational hypertension A sustained rise of blood pressure to 140/90 mm of Hg or more on at least two occasions 4 or more hours apart beyond the 20th week of pregnancy or within the first 48 hours of delivery in a previously normotensive women DC Dutta`s textbook of obstetrics 8th edition, p- 276 It should fulfill the following criteria: - Absence of any evidences for the underlying cause of hypertension - Generally unassociated with other evidences of pre-eclampsia (edema or proteinuria) - Majority of cases are more than or equal to 37 weeks of pregnancy - Generally not associated with hemo-concerntation or thrombocytopenia, raised serum uric acid level or hepatic dysfunction -The blood pressure should come down to normal within 12 weeks following pregnancy DC Dutta`s textbook of obstetrics 8th edition, p- 256 Gestational hypertension: Pathophysiology Cardiovascular effects Elevated BP Increased cardiac output Hematologic effects Third spacing of fluid due to increased blood pressure and decreased plasma oncotic pressure Renal effects Atherosclerotic like changes in renal vessels (glomerular endotheliosis)
decreased glomerular filtration rate and proteinuria Uric acid filtration is decreased module of dapinderjit gill, rose university Pathophysiology (cont.) Neurologic effects Hyper-reflexia/hypersensitivity (does not correlate with severity of disease) In severe cases, grand mal seizures Pulmonary effects Pulmonary edema may occur due to decreased colloid oncotic pressure Fetal effects (severe gestational HTN) Vasospasm Decreased intermittent placental perfusion IUGR, oligo-hydramnios, low birth weight module of dapinderjit gill, rose university Mechanisms Uterine vascular changes Trophoblastic-mediated vascular changes decreased musculature in spiral arterioles development of low resistance, low pressure, high-flow system Inadequate maternal vascular response Endothelial damage is also noted within the vessels Hemostatic changes Increased PLT activation with increased endothelial fibro-nectin and decreased anti-thrombin III and alpha-2antiplasmin further endothelial damage is thought to promote further vasospasm module of dapinderjit gill, rose university Changes in prostanoids During pregnancy, both PGI2 (vasodilation and decreased PLT aggregation) andTXA2 (vasoconstriction and PLT aggregation) are increased with balance favored to PGI2 In preeclampsia,TXA2 is favored Changes in endothelium-derived factors Decrease in Nitric oxide
promoting vasoconstriction module of dapinderjit gill, rose university Transient Hypertension • Retrospective diagnosis • BP normal by 12 weeks postpartum • May recur in subsequent pregnancies • Predictive of future primary hypertension The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation andTreatment of High Blood Pressure HELLP Syndrome He-hemolysis EL-elevated liver enzymes LP-low platelets DC Dutta`s textbook of obstetrics 8th edition,p- 258 Is a variant of severe preeclampsia Platelets < 100,000 LFT’s - 2 x normal May occur against a background of what appears to be mild disease DC Dutta`s textbook of obstetrics 8th edition, p258 Management of HELLP syndrome: Immediate hospitalisation Stabilise mother Antihypertensive Anti-seizure prophylaxis Correct coagulation abnormalities Assess foetal condition- FHR, Doppler ultrasound, biophysical profile DC Dutta`s textbook of obstetrics 8th edition,p258 Eclampsia Definition Pre-eclampsia when complicated with grandmal seizures (generalized tonic clonic seizures) and/or coma is called eclampsia DC Dutta`s textbook of obstetrics 8th edition,p- 268 Incidence and prevalence •0.1- 5.5 per 10,000 pregnancies •Decreasing incidence with time
•Antepartum(50%): mostly in third trimester •Intrapartum (30%): •Postpartum(20%): usually within 48hours, fits beyond 7days generally rules out eclampsia The American college of obstetricians and gynocolists DC Dutta`s textbook of obstetrics 8th edition,p- 268 Risk factors: • Maternal age less than 20 years • Multigravida • Molar pregnancy •Triploidy • Pre-existing hypertension or renal disease • Previous severe Preeclampsia or Eclampsia • Nonimmune hydrops fetalis • Systemic Lupus Erythematosus DC Dutta`s textbook of obstetrics 8th edition,p-268 Clinical Features Eclamptic convulsions are epileptiform and consist of four stages • Premonitory stage: twitching of muscles of face, tongue, limbs and eye. Eyeballs rolled or turned to one side •Tonic stage: opisthotonus, limbs flexed, hands clenched • Clonic stage: 1-4 min, frothing, tongue bite, stertorous breathing • Stage of coma: variable period DC Dutta`s textbook of obstetrics 8th edition,p-270 Pathogenesis: Loss of normal cerebral auto regulatory mechanisms cerebral hyperperfusion leading to Edema & ↓cerebral blood flow. DC Dutta`s textbook of obstetrics 8th edition,p-268 Diagnosis: Lab Investigations: • Complete Blood Count • Platelet count • LFT • RFT • Urine analysis • Serum electrolytes • Peripheral blood smear
• Prothrombin time • Type and screen antibody if present • Angiotensin II test: a dose of 8mk/kg/body weight to increase Diastolic Blood pressure by 20 mm of Hg is taken as positive The American college of obstetricians and gynocolists Differential diagnosis Epilepsy Hysteria Encephalitis Meningitis Puerperal cerebral thrombosis Poisoning Cerebral malaria Intracranial tumor DC Dutta`s textbook of obstetrics 8th edition,p-270 Management Control Hypertension Improve intravascular volume Prevent convulsions Prevent complications Deliver viable fetus DC Dutta`s textbook of obstetrics 8th edition,p-271 Control Hypertension: Most commonly, for acute control: Hydralazine Labetalol Nifedipine may be used, but unexpected hypotension may occur when given with MgSO4 For refractory hypertension: nitroglycerin or nitroprusside may be used Nitroprusside dose and duration should be limited to avoid fetal cyanide toxicity Usually require invasive arterial pressure monitoring Angiotensin-converting enzyme (ACE) inhibitors contraindicated due to severe adverse fetal effect DC Dutta`s textbook of obstetrics 8th edition,p-271-72 Anti-Hypertensive Drugs:
Improve intravascular volume: Main aim is to increase CVP & PCWP range 4-6 cm H2O & 5-10 mm HG and to increase urine output to 1 ml/kg/hr. There is a controversy between colloid and crytalloid as both complicates the condition causing low colloid oncotic pressure and leaky capillary predisposing them to risk of non- carcinogenic pulmonary oedema Fluid recommendation: crystalloids to be administered at the rate of 1-2 ml/kg/hr. and alternating according to CVP, PCWP and Urine Output. DC Dutta`s textbook of obstetrics 8th edition,p-272-73 The American college of obstetricians and gynocolists Seizure Prophylaxis &Treatment: Magnesium sulphate therapy. Magnesium sulfate has many effects; its mechanism in seizure control is not clear. It is an NMDA (N-methyl-D-aspartate) antagonist vasodilator Brain parenchymal vasodilation demonstrated in preeclamptics by Doppler ultrasonography increases release of prostacyclin DC Dutta`s textbook of obstetrics 8th edition,p-272-73 The American college of obstetricians and gynocolists Potential adverse effects: • Toxicity from overdose (respiratory, cardiac) • Bleeding • Hypotension with haemorrhage Uterine contractility Renally excreted Preeclamptics prone to renal failure Magnesium levels must be monitored frequently either clinically (patellar reflexes) or by checking serum levels for 6-8 hours DC Dutta`s textbook of obstetrics 8th edition,p-272-73 The American college of obstetricians and gynocolists Treatment of magnesium toxicity: - Stop MgSO4 - IV 1 g 10% calcium gluconate slow - Administer Oxygen - Secure airway - Ventilation DC Dutta`s textbook of obstetrics 8th edition,p-273 The American college of obstetricians and gynocolists Anaesthetic Implication: MgSo4 potentiate and prolongs both actions of depolarizing and non-depolarizing Muscle relaxants. Intubating dose of succinylcholine should not be decreased as onset and duration of action of single dose does not alter in preeclamptic patients. NDMR when used neuromuscular monitoring with peripheral nerve stimulation and dose titration should be done accordingly. DC Dutta`s textbook of obstetrics 8th edition The American college of obstetricians and gynocolists Various Regime of Magnesium Therapy • Pritchard Regime: - Loading dose: 4g (20 ml of 20%) MgSo4 IV over 4 min. immediately followed by 10g (20 ml of 50%) IM i.e. 5 gm in each buttocks - If convulsion persists after 15 min 2 g IV over 2 min - Maintenance dose: 5g IM every 4 hours alternate side
• Zuspan or Sibai regime: - Loading dose: 6 g IV over 20 min - Maintenance dose: 2-3 g/hr. IV every 6 hr The American college of obstetricians and gynocolists Treatment of Eclampsia: Seizures are usually short-lived. • If necessary, small doses of barbiturate or benzodiazepine (STP, 50 mg, or midazolam, 1-2 mg) and supplemental oxygen by mask • If seizure persists or patient is not breathing, rapid sequence induction with cricoid pressure and intubation should be performed • Patient may be extubated once she is completely awake, recovered from neuromuscular blockade, and magnesium sulfate has been administered The American college of obstetricians and gynocolists Superimposed pre-eclampsia or eclampsia Occurrence of new onset of proteinuria in women with chronic hypertension Risk factors: Renal insufficiency History of hypertension for 4 years or more Hypertension in previous pregnancy DC Dutta`s textbook of obstetrics 8th edition,p- 255 Proteinuria (albuminuria) It is urinary protein greater than 0.3gm/L in 24 hours collection or greater than 1gm/L in two random samples obtained at least 6 hours apart It indicates glomerular damage and almost always occurs after hypertension Proteinuria is usually in the range of 1-3 gm daily, of which 50-60% is albumin but in severe cases it may exceed 15gm DC Dutta`s textbook of obstetrics 8th edition, p- 256 Treating hypertension during lactation Hypertensive mothers can usually breast-feed safely. Antihypertensive drugs are excreted into human breast milk. Therefore, in mothers with stage 1 hypertension who wish to breast-feed for a few months, it might be prudent to withhold antihypertensive medication, with close monitoring of BP, and reinstitute antihypertensive therapy following discontinuation of nursing. No short-term adverse effects have been reported from exposure to methyldopa or hydralazine. Propanolol and labetalol are preferred if a beta-blocker is indicated. ACEIs and ARBs should be avoided, based on reports of adverse fetal and neonatal renal effects. Diuretics may reduce milk volume and thereby suppress lactation. Breast-fed infants of mothers taking antihypertensive agents should be closely monitored for potential adverse effects.