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 in labour has severe back pain with each contraction. The fetus is in an occiput posterior position. Which measure is most likely to help?

  1. AHolding her breath and pushing with each contraction
  2. BAvoiding movement until full dilation
  3. CSacral counterpressure and a hands-and-knees position
  4. DLying flat on her back with her legs raised
2.Maternity & obstetric nursingHard

An ultrasound at 30 weeks shows polyhydramnios and no visible fetal stomach bubble. Which fetal condition should be considered?

  1. AOesophageal atresia
  2. BRenal agenesis
  3. CFetal growth from maternal diabetes only
  4. DPost-term pregnancy
3.Dosage calculationsMedium
20%w/vV = ? mL

A dose of 500 mg is needed from a 20% (w/v) solution. What volume V contains this dose?

500 mg20% w/v
V = mL
4.Dosage calculationsHard
10%stockV₁ = ? mL

You must prepare 200 mL of a 2% (w/v) solution from a 10% (w/v) stock solution. What volume of stock V₁ do you need?

C₁ = 10%C₂ = 2%V₂ = 200 mL
V₁ = mL
5.IV infusion ratesMedium
20 gtt/mL120 mL/h? gtt/min

An infusion is ordered at 120 mL/h, but no pump is available. It runs by gravity through a giving set of 20 gtt/mL. Find the drip rate R in drops per minute.

120 mL/h20 gtt/mL
R = gtt/min
6.IV infusion ratesHard
500 mg250 mL25 mL/h? mg/h

A bag contains 500 mg of a drug in 250 mL and runs at 25 mL/h. How many milligrams per hour D does the patient receive?

500 mg/250 mL25 mL/h
D = mg/h

3Solutions

1.Maternity & obstetric nursing

Answer: C · Sacral counterpressure and a hands-and-knees position

Why this is the answer

In occiput posterior positions the fetal head presses on the sacrum. Counterpressure on the lower back and positions such as hands-and-knees or leaning forward ease pain and may help the head rotate.

Answer

C · Sacral counterpressure and a hands-and-knees position
2.Maternity & obstetric nursing

Answer: A · Oesophageal atresia

Why this is the answer

If the fetus cannot swallow, as in oesophageal atresia, amniotic fluid builds up and the stomach is not seen. Renal agenesis causes the opposite, severe oligohydramnios.

Answer

A · Oesophageal atresia
3.Dosage calculations

Answer: V = 2.5 mL

Solution strengths: a percentage strength is grams per 100 mL, so 1% = 1 g/100 mL = 10 mg/mL. A ratio strength 1:1000 means 1 g in 1000 mL = 1 mg/mL; 1:10 000 is 0.1 mg/mL. For a dilution the amount of drug stays the same: C₁·V₁ = C₂·V₂.

Concentration

20% = 200 mg/mL

Volume

V = 500/200 = 2.5 mL

Answer

V = 2.5 mL
4.Dosage calculations

Answer: V₁ = 40 mL

Solution strengths: a percentage strength is grams per 100 mL, so 1% = 1 g/100 mL = 10 mg/mL. A ratio strength 1:1000 means 1 g in 1000 mL = 1 mg/mL; 1:10 000 is 0.1 mg/mL. For a dilution the amount of drug stays the same: C₁·V₁ = C₂·V₂.

Volume of stock

V₁ = 2·200/10 = 40 mL

Answer

V₁ = 40 mL
5.IV infusion rates

Answer: R = 40 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.

Millilitres per minute

120/60 = 2 mL/min

Drip rate

R = 2·20 = 40 gtt/min

Answer

R = 40 gtt/min
6.IV infusion rates

Answer: D = 50 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

500/250 = 2 mg/mL

Dose rate

D = 2·25 = 50 mg/h

Answer

D = 50 mg/h

ExamProblems · examproblems.com/courses/maternity-nursing