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 with pre-existing type 1 diabetes is pregnant. How do her insulin needs usually change?

  1. AThey rise in the first trimester and fall in the third
  2. BThey often fall early on and then rise later in pregnancy
  3. CThey stay the same throughout pregnancy
  4. DInsulin is stopped during pregnancy and restarted after birth
2.Maternity & obstetric nursingHard

On abdominal palpation, the nurse feels a hard, round, movable mass in the fundus, and the fetal heart is heard above the umbilicus. What does this suggest?

  1. AA breech presentation
  2. BAn occiput posterior position
  3. CA cephalic presentation
  4. DA transverse lie with the head in the pelvis
3.Dosage calculationsMedium
12 kg20 mg/kg/day4× per dayD = ? mg

A patient weighs 12 kg. The prescribed dose is 20 mg/kg per day, given in 4 equal doses. How many milligrams D are given per dose?

12 kg20 mg/kg/day4× per day
D = mg
4.Dosage calculationsHard
100 mg/1 mLV = ? mL

A patient weighs 90.2 lb. The prescription is 0.5 mg/kg as a single dose, and the stock contains 100 mg in 1 mL. Using 1 kg = 2.2 lb, what volume V do you give? Round to two decimal places.

90.2 lb0.5 mg/kg100 mg/1 mL1 kg = 2.2 lb
V = mL
5.IV infusion ratesMedium
V = ?15 gtt/mL40 gtt/min2 h

A drip runs at 40 gtt/min through a set of 15 gtt/mL. How many millilitres V does the patient receive in 2 hours?

40 gtt/min15 gtt/mL2 h
V = mL
6.IV infusion ratesHard
100 mg50 mL12 mL/h? mg/h

A bag contains 100 mg of a drug in 50 mL and runs at 12 mL/h. How many milligrams per hour D does the patient receive?

100 mg/50 mL12 mL/h
D = mg/h

3Solutions

1.Maternity & obstetric nursing

Answer: B · They often fall early on and then rise later in pregnancy

Why this is the answer

In early pregnancy, nausea and increased insulin sensitivity can lower insulin needs and raise the risk of hypoglycaemia. Insulin resistance from placental hormones then raises needs markedly in the second and third trimesters.

Answer

B · They often fall early on and then rise later in pregnancy
2.Maternity & obstetric nursing

Answer: A · A breech presentation

Why this is the answer

A hard, round, ballotable head in the fundus means the buttocks are presenting. The fetal heart in breech presentations is usually heard above the umbilicus.

Answer

A · A breech presentation
3.Dosage calculations

Answer: D = 60 mg

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.

Total per day

20·12 = 240 mg

Per dose

D = 240/4 = 60 mg

Answer

D = 60 mg
4.Dosage calculations

Answer: V = 0.21 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

90.2/2.2 = 41 kg

Dose

0.5·41 = 20.5 mg

Volume

V = (20.5/100)·1 = 0.205 ≈ 0.21 mL

Answer

V = 0.21 mL
5.IV infusion rates

Answer: V = 320 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

40·60/15 = 160 mL/h

Volume

V = 160·2 = 320 mL

Answer

V = 320 mL
6.IV infusion rates

Answer: D = 24 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

100/50 = 2 mg/mL

Dose rate

D = 2·12 = 24 mg/h

Answer

D = 24 mg/h

ExamProblems · examproblems.com/courses/maternity-nursing