Hypertensive disorders and magnesium sulfate
Gestational hypertension is a blood pressure of 140/90 or higher on two occasions after 20 weeks in a previously normotensive client. It becomes preeclampsia when proteinuria appears, and preeclampsia with severe features when the pressure reaches 160/110 or when signs of end-organ involvement develop. Those severe-feature signs are the ones the exam wants you to escalate: persistent headache unrelieved by analgesia, visual disturbance such as blurring or scotomata, epigastric or right upper quadrant pain, oliguria, and rising liver enzymes or falling platelets.
Epigastric pain deserves special attention because students often misread it as indigestion. It reflects hepatic capsule distension and is a warning of imminent seizure or of HELLP syndrome, defined by haemolysis, elevated liver enzymes and low platelets. Eclampsia is preeclampsia with seizure, and the nursing response follows seizure principles: protect the airway, turn the client to the side, do not restrain, do not insert anything in the mouth, and administer magnesium.
Magnesium sulfate is the anticonvulsant of choice and is given as a loading dose followed by a continuous infusion on a pump. Its therapeutic effect is central nervous system depression, which is also the source of its danger. Monitoring is a fixed checklist: deep tendon reflexes, respiratory rate, urine output and level of consciousness, along with continuous fetal monitoring. The earliest sign of toxicity is loss of the patellar reflex, followed by a respiratory rate below 12, then oliguria, then cardiac arrest.
The nurse withholds the infusion and notifies the provider if reflexes are absent, respirations fall below 12 per minute, or urine output drops below 30 millilitres per hour, because magnesium is renally excreted and oliguria causes accumulation. Calcium gluconate is the antidote and must be immediately available at the bedside. The environment is kept quiet and dimly lit with seizure precautions in place, and the client is positioned in a left lateral tilt to optimise placental perfusion.
| Parameter | Safe finding | Action if abnormal |
|---|---|---|
| Deep tendon reflexes | Present, 1+ to 2+ | Absent — stop infusion, notify provider |
| Respiratory rate | Above 12 per minute | Below 12 — stop, give oxygen, calcium gluconate ready |
| Urine output | Above 30 mL per hour | Below 30 — stop and notify; risk of accumulation |
| Level of consciousness | Alert or mildly drowsy | Marked lethargy — assess for toxicity |
| Fetal heart rate | Reassuring baseline | Decreased variability — notify provider |
Third-trimester bleeding: previa versus abruption
Placenta previa occurs when the placenta implants over or near the cervical os. Its signature is painless, bright red vaginal bleeding, usually beginning late in the second or in the third trimester, with a soft non-tender uterus and a fetus that is often in a malpresentation because the placenta blocks engagement. The absolute rule is that no vaginal or rectal examination is performed, because digital examination can perforate the placenta and cause catastrophic haemorrhage. Diagnosis is by ultrasound, and delivery is by caesarean section when the placenta covers the os.
Placental abruption is premature separation of a normally implanted placenta. Its signature is sudden, sharp, continuous abdominal pain with dark red bleeding and a uterus that is rigid, board-like and tender. Bleeding may be concealed behind the placenta, so the amount of visible blood can badly understate the loss — an important reason to trust the uterine findings and the maternal vital signs over the pad count. Risk factors include hypertension, trauma, cocaine use, and previous abruption.
For both conditions the nursing priorities overlap: continuous maternal and fetal monitoring, large-bore intravenous access, type and crossmatch, strict intake and output, assessment of blood loss by weighing pads, left lateral positioning, oxygen as indicated, and preparation for emergency caesarean delivery. Disseminated intravascular coagulation is a recognised complication of abruption and should be suspected with oozing from puncture sites.
- •Previa — painless, bright red, soft uterus, no vaginal exam
- •Abruption — painful, dark red or concealed, rigid tender uterus
- •Both — IV access, crossmatch, continuous monitoring, prepare for caesarean
- •Weigh pads: one gram equals approximately one millilitre of blood
Gestational diabetes and hyperemesis gravidarum
Gestational diabetes arises when placental hormones create insulin resistance that the pancreas cannot overcome. Screening is usually performed between 24 and 28 weeks. Management begins with dietary modification and moderate exercise, adding insulin when targets are not met; oral agents are used selectively, and insulin remains the exam's default answer because it does not cross the placenta.
The complications drive the questions. Maternal risks include preeclampsia, polyhydramnios, urinary tract and vaginal infections, and a higher caesarean rate. Fetal risks centre on macrosomia, which increases the risk of shoulder dystocia and birth trauma, along with congenital anomalies in pre-existing diabetes. After birth the neonate is at high risk of hypoglycaemia, because fetal insulin production remains high once the maternal glucose supply stops, so blood glucose is checked within the first hour and early feeding is initiated. Jitteriness, poor feeding, temperature instability and a weak cry are the newborn hypoglycaemia signs to know.
Hyperemesis gravidarum is persistent vomiting causing weight loss above five per cent of pre-pregnancy weight, dehydration, ketonuria and electrolyte imbalance. It differs from ordinary morning sickness in severity and consequence. Nursing management includes intravenous fluid and electrolyte replacement, keeping the client nil by mouth initially and then advancing slowly with small dry frequent meals, antiemetics such as pyridoxine with doxylamine or ondansetron, daily weights, strict intake and output, and monitoring for the ketosis that signals inadequate intake.
- •Insulin is the preferred pharmacological therapy in pregnancy
- •Macrosomia raises shoulder dystocia and caesarean risk
- •Check neonatal glucose within the first hour after birth
- •Hyperemesis: weight loss, ketonuria, electrolyte imbalance, IV rehydration
Answering maternity complication items
Two principles carry most maternity questions. First, there are always two clients, so an intervention that helps the mother but compromises placental perfusion is wrong. Left lateral positioning, adequate hydration and oxygen recur as answers for exactly this reason. Second, the fetal heart rate pattern is an early warning system: late decelerations indicate uteroplacental insufficiency, variable decelerations indicate cord compression, and both require intrauterine resuscitation measures.
Practise these scenarios in mixed sets alongside labour, postpartum and newborn content so that you learn to identify the phase of care before reasoning. Our maternal and newborn question sets and full-length mock exams include high-risk pregnancy items with complete rationales for every option.