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

A postpartum woman who is not immune to rubella receives the vaccine before discharge. What advice is essential?

  1. AStop breastfeeding for 4 weeks
  2. BAvoid becoming pregnant for at least 4 weeks
  3. CHave the vaccine repeated in 6 months
  4. DKeep away from her newborn for 2 days
2.Maternity & obstetric nursingHard

A woman at 26 weeks has a haemoglobin of 95 g/L (9.5 g/dL) and a low ferritin. She is already taking oral iron but has severe side effects. What might be considered?

  1. ADoubling her caffeine intake
  2. BA routine blood transfusion
  3. CIntravenous iron
  4. DStopping iron and waiting until after birth
3.Dosage calculationsMedium
024681010 mL

A child weighing 16 kg is prescribed 10 mg/kg of a drug. The stock solution contains 20 mg/mL. Draw up the dose: what volume V do you give?

16 kg10 mg/kg20 mg/mL
V = mL
4.Dosage calculationsHard
40 mg/1 mLV = ? mL

A patient weighs 50.6 lb. The prescription is 15 mg/kg as a single dose, and the stock contains 40 mg in 1 mL. Using 1 kg = 2.2 lb, what volume V do you give? Round to one decimal place.

50.6 lb15 mg/kg40 mg/1 mL1 kg = 2.2 lb
V = mL
5.IV infusion ratesMedium
1000 mL10 gtt/mL3 h? gtt/min

Infuse 1000 mL over 3 hours with a giving set of 10 gtt/mL. Find the drip rate R in drops per minute. Round to the nearest whole number.

1000 mL3 h10 gtt/mL
R = gtt/min
6.IV infusion ratesHard
400 mg50 mL20 mL/h? mg/h

A bag contains 400 mg of a drug in 50 mL and runs at 20 mL/h. How many milligrams per hour D does the patient receive?

400 mg/50 mL20 mL/h
D = mg/h

3Solutions

1.Maternity & obstetric nursing

Answer: B · Avoid becoming pregnant for at least 4 weeks

Why this is the answer

The rubella vaccine contains a live attenuated virus, so pregnancy should be avoided for at least 4 weeks after vaccination. It is compatible with breastfeeding.

Answer

B · Avoid becoming pregnant for at least 4 weeks
2.Maternity & obstetric nursing

Answer: C · Intravenous iron

Why this is the answer

When oral iron is not tolerated or not effective, intravenous iron may be used in the second and third trimesters. Transfusion is reserved for severe or symptomatic anaemia or acute blood loss.

Answer

C · Intravenous iron
3.Dosage calculations

Answer: V = 8 mL

Drawing up a dose: volume = (prescribed dose/stock strength) × stock volume. Convert to the same units first, then check that the volume fits the syringe and lands on one of its graduations.

Dose from body weight

D = 10·16 = 160 mg

Volume

V = 160/20 = 8 mL

On the syringe

On this 10 mL syringe every small line is 0.2 mL.

Answer

V = 8 mL
4.Dosage calculations

Answer: V = 8.6 mL

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.

Weight in kg

50.6/2.2 = 23 kg

Dose

15·23 = 345 mg

Volume

V = (345/40)·1 = 8.625 ≈ 8.6 mL

Answer

V = 8.6 mL
5.IV infusion rates

Answer: R = 56 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

3·60 = 180 min

Drip rate

R = 1000·10/180 = 55.56 ≈ 56 gtt/min

Answer

R = 56 gtt/min

At the bedside you round to the nearest whole drop: 56 gtt/min.

6.IV infusion rates

Answer: D = 160 mg/h

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.

Concentration

400/50 = 8 mg/mL

Dose rate

D = 8·20 = 160 mg/h

Answer

D = 160 mg/h

ExamProblems · examproblems.com/courses/maternity-nursing