A nurse is planning to administer phytonadione 0.5 mg to a newborn.

Available is 1 mg/0.5 mL. How many mL should the nurse administer? (Round the answer to the nearest hundredth.

Use a leading zero if it applies.

Do not use a trailing zero.)

Choice A rationale

Nalbuphine hydrochloride is a synthetic opioid agonist-antagonist analgesic often used for pain relief during labor. Its agonist effects on kappa (κ) opioid receptors in the central nervous system lead to analgesia and common side effects, including central nervous system depression. Sedation is a frequent manifestation of this effect, caused by the drug's action on brain centers controlling arousal.

Choice B rationale

Nalbuphine primarily acts as an opioid, and its μ-receptor antagonist activity counteracts some opioid effects, but typical opioid-related gastrointestinal effects include decreased peristalsis, often leading to constipation. Diarrhea is not a common or expected adverse effect of nalbuphine; instead, it tends to slow gut motility due to its opioid effects on the enteric nervous system.

Choice C rationale

Opioid use, including nalbuphine, can sometimes lead to the adverse effect of urinary retention, due to increased detrusor muscle tone and internal sphincter spasm, which is a suppression of the micturition reflex. Diuresis, which is an increased or excessive production of urine, is not a recognized adverse effect of this medication.

Choice D rationale

Opioids, such as nalbuphine, typically interact with the thermoregulatory centers in the hypothalamus, often resulting in hypothermia due to vasodilation and decreased metabolic rate, not fever. Fever (pyrexia) is not a common or characteristic adverse effect associated with the administration of nalbuphine hydrochloride during labor.

Choice A rationale

This statement is incorrect. While lactational amenorrhea method (LAM) offers some protection, it is only highly effective under strict conditions: amenorrhea, exclusive breastfeeding, and less than six months postpartum. Ovulation can resume even while breastfeeding, so additional contraception is often necessary to prevent unintended pregnancy.

Choice B rationale

There is no scientific evidence to support the claim that taking birth control pills while breastfeeding increases the risk for breast cancer. This statement is false and should not be used to counsel the client. The primary concern with combined estrogen-progestin pills in lactating women is the potential suppression of milk supply.

Choice C rationale

Combined estrogen-progestin birth control pills are generally contraindicated or strongly discouraged during the initial weeks to months of breastfeeding. The estrogen component can decrease the quantity and quality of breast milk, potentially interfering with successful lactation. However, progestin-only pills are considered safe and not contraindicated.

Choice D rationale

Progestin-only birth control pills (the "mini-pill") are the preferred hormonal contraceptive for lactating clients. The absence of estrogen means they are less likely to negatively impact breast milk supply or composition. Progestin-only pills primarily work by thickening cervical mucus and inhibiting ovulation, offering effective contraception while minimizing risks to the breastfeeding infant.