Maternity Nursing: cram pack

Formula sheets, the key method steps for every topic and 6 practice problems, with full solutions at the back.

New problemsBack to the course

In the print window, choose “Save as PDF” to keep a copy on your device.

1Formulas and methods

Maternity & obstetric nursing

Method

  1. Place the woman in time: weeks of pregnancy, stage of labour or day after birth, and decide what is normal at that point.
  2. Look for the patient in danger: the mother, the fetus or the newborn, or more than one of them.
  3. Link the finding to its cause: VEAL CHOP for decelerations, the four Ts for bleeding, BUBBLE-HE after birth.
  4. Choose the action that improves blood flow and oxygen first (side-lying, stopping oxytocin, fundal massage), then escalate.

Dosage calculations

Dose from strength
volume = dose / strength
Weight-based dose
dose = mg/kg × body weight
Tablets
number = dose / tablet strength
Units
1 g = 1000 mg, 1 mg = 1000 mcg

Method

  1. Convert the ordered dose and the stock strength to the same unit.
  2. Use desired over have times quantity: (D/H) × Q.
  3. For weight-based doses, multiply by the weight in kg first, then divide the daily dose by the number of doses.
  4. Estimate first and check that the answer is reasonable.

IV infusion rates

Pump rate
mL/h = volume (mL)/time (h)
Drip rate
drops/min = volume (mL) × drop factor / time (min)
Infusion time
time (h) = volume (mL)/rate (mL/h)

Method

  1. Pump rate in mL/h: volume divided by time in hours.
  2. Drip rate in drops/min: volume × drop factor divided by time in minutes.
  3. For time remaining: volume left divided by the rate.
  4. Round as the question or the equipment requires.

2Practice problems

1.Maternity & obstetric nursingMedium

During birth the baby's head is delivered but the shoulders are stuck. Which first manoeuvre is standard?

  1. APushing the head back into the vagina as a first step
  2. BMcRoberts manoeuvre with suprapubic pressure
  3. CFirm pressure on the fundus
  4. DPulling hard on the baby's head
2.Maternity & obstetric nursingHard

Which newborn finding requires immediate follow-up?

  1. ASmall white spots (milia) on the nose
  2. BAcrocyanosis at 2 hours
  3. CGrunting, nasal flaring and chest retractions at 1 hour
  4. DMoulding of the head shape after a vaginal birth at term
3.Dosage calculationsMedium
48 kgBSA = 1.31 m²50 mg/m²D = ? mg

A patient weighing 48 kg has a body surface area of 1.31 m². The prescription is 50 mg/m². Find the dose D in mg.

48 kgBSA = 1.31 m²50 mg/m²
D = mg
4.Dosage calculationsHard
40k units250 mL? mL/h1500 units/h

An infusion contains 40000 units of a drug in 250 mL. The prescription is 1500 units per hour. At what rate R do you set the pump, in mL/h?

40000 units/250 mL1500 units/h
R = mL/h
5.IV infusion ratesMedium
1000 mL15 gtt/mL6 h? gtt/min

Infuse 1000 mL over 6 hours with a giving set of 15 gtt/mL. Find the drip rate R in drops per minute. Round to the nearest whole number.

1000 mL6 h15 gtt/mL
R = gtt/min
6.IV infusion ratesHard
4 g500 mL? mL/h1.5 mg/min

A bag contains 4 g of a drug in 500 mL. The order is 1.5 mg per minute. At what rate R do you set the pump, in mL/h?

4 g/500 mL1.5 mg/min
R = mL/h

3Solutions

1.Maternity & obstetric nursing

Answer: B · McRoberts manoeuvre with suprapubic pressure

Why this is the answer

For shoulder dystocia, call for help, flex the woman's thighs sharply onto her abdomen (McRoberts) and apply suprapubic, not fundal, pressure. Fundal pressure and strong traction on the head can worsen the impaction and injure the baby.

Answer

B · McRoberts manoeuvre with suprapubic pressure
2.Maternity & obstetric nursing

Answer: C · Grunting, nasal flaring and chest retractions at 1 hour

Why this is the answer

Grunting, flaring and retractions are signs of respiratory distress and need urgent assessment. Acrocyanosis, milia and moulding are common normal findings.

Answer

C · Grunting, nasal flaring and chest retractions at 1 hour
3.Dosage calculations

Answer: D = 65.5 mg

Body-surface-area dosing: many cytotoxic and some paediatric doses are prescribed per square metre of body surface area: dose (mg) = dose per m² × BSA (m²). The Mosteller formula estimates BSA = √(height (cm) × weight (kg)/3600).

Dose

D = 50·1.31 = 65.5 mg

Answer

D = 65.5 mg
4.Dosage calculations

Answer: R = 9.375 mL/h

Dose calculation: the amount to give equals what is prescribed divided by what you have, times the quantity it comes in: amount = (desired dose/stock strength) × stock volume. Always keep the units the same (convert g to mg, mg to mcg first) and check that the answer is sensible.

Concentration

40000/250 = 160 units/mL

Pump rate

R = 1500/160 = 9.375 mL/h

Answer

R = 9.375 mL/h
5.IV infusion rates

Answer: R = 42 gtt/min

Infusion rates: a pump is set in mL/h = volume/time in hours. A gravity drip is counted in drops per minute: gtt/min = volume (mL) × drop factor (gtt/mL)/time (min). The drop factor is printed on the tubing package: macrodrip sets deliver 10, 15 or 20 gtt/mL (blood sets often 10 gtt/mL in the US, 15 in the UK) and microdrip sets 60 gtt/mL. Always use the drop factor the question or package gives.

Time in minutes

6·60 = 360 min

Drip rate

R = 1000·15/360 = 41.67 ≈ 42 gtt/min

Answer

R = 42 gtt/min

At the bedside you round to the nearest whole drop: 42 gtt/min.

6.IV infusion rates

Answer: R = 11.25 mL/h

Dose-based infusions: concentration = amount of drug in the bag/bag volume. Pump rate (mL/h) = dose per hour/concentration, and dose per hour = mL/h × concentration. Convert per-minute doses to per-hour (× 60) and keep the mass units the same (1 g = 1000 mg, 1 mg = 1000 mcg).

Concentration

4000 mg/500 mL = 8 mg/mL

Dose per hour

1.5·60 = 90 mg/h

Pump rate

R = 90/8 = 11.25 mL/h

Answer

R = 11.25 mL/h

ExamProblems · examproblems.com/courses/maternity-nursing