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 woman at 10 weeks has morning sickness. Which suggestion is most likely to help?

  1. ADrink large amounts of fluid with each meal
  2. BEat dry crackers before rising and eat small meals
  3. CSkip breakfast and eat one large meal in the evening
  4. DEat spicy and fatty foods to settle the stomach
2.Maternity & obstetric nursingHard

A woman in labour is 8 cm dilated. The fetal heart rate shows decelerations that begin and end with each contraction and mirror its shape, with moderate variability. What is appropriate?

  1. AContinue to monitor; this pattern is benign
  2. BTurn off the monitor to reduce anxiety
  3. CStop all fluids
  4. DPrepare for an emergency caesarean birth
3.Dosage calculationsMedium
500 mg+ 4.6 mLV = ? mL

A vial contains 500 mg of powder. The label says: add 4.6 mL of water for injection to give a total volume of 5 mL. The prescription is 40 mg. What volume V of the reconstituted solution do you give?

500 mg+ 4.6 mL → 5 mL40 mg
V = mL
4.Dosage calculationsHard
20k units1000 mL? mL/h1500 units/h

An infusion contains 20000 units of a drug in 1000 mL. The prescription is 1500 units per hour. At what rate R do you set the pump, in mL/h?

20000 units/1000 mL1500 units/h
R = mL/h
5.IV infusion ratesMedium
V = ?15 gtt/mL20 gtt/min2 h

A drip runs at 20 gtt/min through a set of 15 gtt/mL. How many millilitres V does the patient receive in 2 hours?

20 gtt/min15 gtt/mL2 h
V = mL
6.IV infusion ratesHard
400 mg50 mL5 mL/h? mg/h

A bag contains 400 mg of a drug in 50 mL and runs at 5 mL/h. How many milligrams per hour D does the patient receive?

400 mg/50 mL5 mL/h
D = mg/h

3Solutions

1.Maternity & obstetric nursing

Answer: B · Eat dry crackers before rising and eat small meals

Why this is the answer

Eating something dry before rising, small frequent meals, and drinking fluids between rather than with meals reduce nausea. Fatty and spicy foods tend to worsen it.

Answer

B · Eat dry crackers before rising and eat small meals
2.Maternity & obstetric nursing

Answer: A · Continue to monitor; this pattern is benign

Why this is the answer

These are early decelerations, caused by head compression in active labour. With moderate variability they are reassuring, and no intervention is needed beyond continued monitoring.

Answer

A · Continue to monitor; this pattern is benign
3.Dosage calculations

Answer: V = 0.4 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.

Concentration after mixing

500 mg/5 mL = 100 mg/mL

Volume

V = 40/100 = 0.4 mL

Answer

V = 0.4 mL
4.Dosage calculations

Answer: R = 75 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

20000/1000 = 20 units/mL

Pump rate

R = 1500/20 = 75 mL/h

Answer

R = 75 mL/h
5.IV infusion rates

Answer: V = 160 mL

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.

Rate in mL/h

20·60/15 = 80 mL/h

Volume

V = 80·2 = 160 mL

Answer

V = 160 mL
6.IV infusion rates

Answer: D = 40 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 = 8·5 = 40 mg/h

Answer

D = 40 mg/h

ExamProblems · examproblems.com/courses/maternity-nursing