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

What should parents be taught about the water for a newborn's bath?

  1. ACheck that it is warm, not hot, before the baby goes in
  2. BAdd adult bubble bath to soften the baby's skin
  3. CUse very hot water so that germs on the skin are killed
  4. DLeave the baby briefly if the water is only shallow
2.Maternity & obstetric nursingHard

Why does the ductus arteriosus normally close after birth?

  1. APressure in the pulmonary artery rises
  2. BThe cord is cut, which closes it directly
  3. CRising oxygen levels and falling prostaglandins
  4. DRising prostaglandins and falling oxygen levels
3.Dosage calculationsMedium
500 mg+ 1.8 mLV = ? mL

A vial contains 500 mg of powder. The label says: add 1.8 mL of water for injection to give a total volume of 2 mL. The prescription is 250 mg. What volume V of the reconstituted solution do you give?

500 mg+ 1.8 mL → 2 mL250 mg
V = mL
4.Dosage calculationsHard
00.10.20.30.40.50.60.70.80.911 mL

The prescription is 500 micrograms. The ampoule contains 2 mg/mL. Draw up the dose in the 1 mL syringe: what volume V do you give?

500 mcg2 mg/mL
V = mL
5.IV infusion ratesMedium
V = ?60 gtt/mL50 gtt/min3 h

A drip runs at 50 gtt/min through a set of 60 gtt/mL. How many millilitres V does the patient receive in 3 hours?

50 gtt/min60 gtt/mL3 h
V = mL
6.IV infusion ratesHard
900 mL60 gtt/mL42 gtt/mint = ? h

A drip runs at 42 gtt/min through a set of 60 gtt/mL. There are 900 mL left in the bag. How many hours t until it is empty? Round to one decimal place.

42 gtt/min60 gtt/mL900 mL
t = h

3Solutions

1.Maternity & obstetric nursing

Answer: A · Check that it is warm, not hot, before the baby goes in

Why this is the answer

Bath water should be comfortably warm, about 37 °C (98.6 °F), checked with a thermometer or the elbow, and the baby is never left alone, even in shallow water. Plain water or a mild baby cleanser is used. Some guidance, such as in the US, advises sponge baths until the cord stump has fallen off.

Answer

A · Check that it is warm, not hot, before the baby goes in
2.Maternity & obstetric nursing

Answer: C · Rising oxygen levels and falling prostaglandins

Why this is the answer

Higher blood oxygen and lower prostaglandin levels after birth cause the ductus arteriosus to constrict. Prostaglandin infusions are used to keep it open in duct-dependent heart defects.

Answer

C · Rising oxygen levels and falling prostaglandins
3.Dosage calculations

Answer: V = 1 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/2 mL = 250 mg/mL

Volume

V = 250/250 = 1 mL

Answer

V = 1 mL
4.Dosage calculations

Answer: V = 0.25 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.

Same units

2 mg/mL = 2000 mcg/mL

Volume

V = 500/2000 = 0.25 mL

Answer

V = 0.25 mL
5.IV infusion rates

Answer: V = 150 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

50·60/60 = 50 mL/h

Volume

V = 50·3 = 150 mL

Answer

V = 150 mL
6.IV infusion rates

Answer: t = 21.4 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.

Rate in mL/h

42·60/60 = 42 mL/h

Time left

t = 900/42 = 21.43 ≈ 21.4 h

Answer

t = 21.4 h

ExamProblems · examproblems.com/courses/maternity-nursing