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

Where is the fundus normally found about 12 hours after a vaginal birth?

  1. ABelow the symphysis pubis and not palpable
  2. BFirm, in the midline, at about the level of the umbilicus
  3. CSoft and two finger-widths above the xiphoid process
  4. DFirm and displaced to the far left side
2.Maternity & obstetric nursingHard

A woman with gestational diabetes asks if she will have diabetes after the baby is born. Which reply is accurate?

  1. AIt always becomes type 1 diabetes after birth
  2. BIt usually resolves, but her risk of type 2 diabetes stays higher
  3. CIt never returns, so no further glucose testing is needed after birth
  4. DIt will continue unless she stops breastfeeding
3.Dosage calculationsMedium
1:1000ampouleV = ? mL

An ampoule of epinephrine (adrenaline) is labelled 1:1000 (1 mg/mL). The prescription is 0.5 mg IM for anaphylaxis. What volume V do you draw up?

1:10000.5 mg
V = mL
4.Dosage calculationsHard
00.10.20.30.40.50.60.70.80.911 mL

The prescription is 0.42 mg. The ampoule contains 500 micrograms per mL. Draw up the dose in the 1 mL syringe: what volume V do you give?

0.42 mg500 mcg/mL
V = mL
5.IV infusion ratesMedium
250 mL60 gtt/mL10 h? gtt/min

Infuse 250 mL over 10 hours with a giving set of 60 gtt/mL. Find the drip rate R in drops per minute.

250 mL10 h60 gtt/mL
R = gtt/min
6.IV infusion ratesHard
500 mg100 mL20 mL/h? mg/h

A bag contains 500 mg of a drug in 100 mL and runs at 20 mL/h. How many milligrams per hour D does the patient receive?

500 mg/100 mL20 mL/h
D = mg/h

3Solutions

1.Maternity & obstetric nursing

Answer: B · Firm, in the midline, at about the level of the umbilicus

Why this is the answer

The fundus rises to about the umbilicus within the first 12 hours, then descends about 1 cm (one finger-width) a day. It is usually no longer palpable above the symphysis by about 2 weeks.

Answer

B · Firm, in the midline, at about the level of the umbilicus
2.Maternity & obstetric nursing

Answer: B · It usually resolves, but her risk of type 2 diabetes stays higher

Why this is the answer

Gestational diabetes usually resolves after birth, but the risk of later type 2 diabetes is much higher. She should have a glucose test after birth and regular screening, and keep up a healthy weight and activity.

Answer

B · It usually resolves, but her risk of type 2 diabetes stays higher
3.Dosage calculations

Answer: V = 0.5 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

1:1000 = 1 g/1000 mL = 1 mg/mL

Volume

V = 0.5/1 = 0.5 mL

Answer

V = 0.5 mL

US labels now state mg/mL (1 mg/mL = 1:1000; 0.1 mg/mL = 1:10 000). Never give 1 mg/mL epinephrine IV push.

4.Dosage calculations

Answer: V = 0.84 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

0.42 mg = 420 mcg

Volume

V = 420/500 = 0.84 mL

Answer

V = 0.84 mL
5.IV infusion rates

Answer: R = 25 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

10·60 = 600 min

Drip rate

R = 250·60/600 = 25 gtt/min

Answer

R = 25 gtt/min
6.IV infusion rates

Answer: D = 100 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

500/100 = 5 mg/mL

Dose rate

D = 5·20 = 100 mg/h

Answer

D = 100 mg/h

ExamProblems · examproblems.com/courses/maternity-nursing