Anesthesia in the Breastfeeding Patient: From "Pump and Dump" to "Sleep and Keep"

"The patient can breastfeed or express milk without discarding it as soon as she is awake and alert after anesthesia."

Key takeaways for faster decision-making#

The article's practical rule

• Awake and alert? She can breastfeed/express without discarding.

Logistics for maintaining supply

• Milk supply depends on removal: plan logistics so as not to exceed the longest usual interval; if necessary, consider intraoperative expression.

Analgesia and opioids

• Analgesia is part of successful breastfeeding: scheduled non-opioids + opioid for rescue; avoid codeine, tramadol, and repeated doses of meperidine.

Drug selection without "automatic fear"

• Choose drugs by efficacy and compatibility, not by fear: the majority of perioperative medications are compatible with uninterrupted lactation.

Why abandon "pump and dump"#

It is still common for breastfeeding patients to receive instructions to stop breastfeeding and "discard the milk" after anesthesia.

The problem is that this approach, when adopted indiscriminately, creates unnecessary barriers to breastfeeding and may trigger clinical complications.

Once breastfeeding is established, the mother-infant dyad becomes interdependent, and maintaining supply depends primarily on regular milk removal.

Separation and reduced breast emptying increase the risk of engorgement, mastitis, and decreased milk production.

The practical impact of interruption is significant: fewer than 40% of women who stop breastfeeding are able to successfully resume lactation.

Where the recommendations come from and what is the current operational rule#

The article "Anesthesia Care of Lactating Patients", published in the December 2025 edition of "Advances in Anesthesia", addresses the most recent recommendations from the American Society of Anesthesiologists (ASA), the Academy of Breastfeeding Medicine (ABM), and the Association of Anaesthetists regarding breastfeeding in the perioperative period.

The operational guideline summarizing the current recommendations cited in the article is: the patient can breastfeed or express milk without discarding it as soon as she is awake and alert after anesthesia.

The vast majority of anesthetics and medications used intraoperatively are compatible with breastfeeding.

Attention should be given to exceptions:

• meperidine
• tramadol
• codeine
• iodine-based antiseptics
• some medications for which studies are scarce

Instead of "pump and dump," the text proposes the mnemonic: "sleep and keep."

1) Lactation physiology: what matters for the anesthesiologist#

Lactation is described as a neuroendocrine system with two main axes.

Prolactin (milk production)

During pregnancy, elevated levels of placental progesterone suppress the lactogenic effect of prolactin; after placental delivery, the abrupt drop in progesterone allows prolactin to initiate and maintain production.

Later, prolactin secretion becomes primarily regulated by dopamine through negative feedback.

Practical implication highlighted in the article:

• drugs that increase dopaminergic activity (including dopamine and propofol) may reduce milk supply
• dopamine antagonists (e.g., metoclopramide) may increase production by removing this dopaminergic inhibition

Oxytocin (let-down reflex and bonding)

Oxytocin is released with nipple stimulation by the infant or by use of a breast pump, promoting smooth/myoepithelial muscle contraction and being associated with positive feelings of bonding with the baby.

Colostrum → transitional milk → mature milk

Shortly after delivery, lactocytes are "more loosely connected," with greater permeability; during this phase, colostrum is produced, rich in antibodies and immunological factors.

As tight junctions form, there is greater control over milk composition.

This transition typically occurs within the first 7-14 days, progressing to mature milk.

2) Breastfeeding pharmacology: why "concentration in milk" is not synonymous with risk#

The article describes the passage of medications from maternal blood into milk through two mechanisms.

Passive diffusion (transcellular/paracellular)

Depends on molecular size, protein binding, maternal plasma concentration (which depends on dose and volume of distribution), and lipophilicity.

It is the same logic that explains why anesthetics cross the blood-brain barrier and potentially also the lactocyte barrier.

Active transport

Can occur at all stages and concentrate drugs in milk regardless of size/lipophilicity, if specific transporters exist.

Lactogenesis stage changes permeability and total exposure

In the early postpartum period (colostrum), junctions are more permeable and composition approaches that of maternal plasma; however, the volume produced is very low (milliliters per feed), which limits total infant exposure.

With mature milk, tight junctions between lactocytes provide greater compositional control and tend to reduce drug concentrations in milk; the article describes this as a "paradoxical" relationship in which greater milk volume is associated with lower infant exposure.

The relevant metric is the Relative Infant Dose (RID)

Concentration in milk, by itself, does not represent a risk of exposure.

The relative dose (compared to the weight-adjusted maternal dose) rarely exceeds the theoretical threshold of 10% for most medications; furthermore, many drugs have low oral bioavailability, reducing the fraction absorbed by the infant during feeding.

The article also notes that topical gastrointestinal effects of non-absorbed drugs may occur (e.g., gastrointestinal discomfort after maternal antibiotics).

3) Drug selection by class#

Simple decision rule proposed in the article

When pharmacological treatment is needed, evaluate the standard evidence-based treatment for the clinical condition; then evaluate compatibility with breastfeeding.

If necessary, prefer suitable second-line therapies rather than automatically switching to inferior alternatives.

3.1 Anesthetics and sedatives

Central principle

Anesthetics (small lipophilic molecules) redistribute and are eliminated rapidly after administration ceases; passage into milk follows the gradient and decreases as plasma concentration falls.

It is a bidirectional process, and it is not necessary to empty the breasts to "clear" medications; moreover, many of these drugs are not orally bioavailable for the infant.

Minimal risk with resumption when the patient is alert and oriented

When the patient is sufficiently awake and oriented, residual concentrations available for infant ingestion are clinically insignificant and represent minimal risk.

Table 1. Anesthetics and sedatives during lactation (according to the article)

Specific observations from the article

• Volatiles: minimal risk due to rapid elimination and low plasma levels at emergence.
• Ketamine: large volume of distribution reduces the chance of concerning concentrations in milk.
• Dexmedetomidine: low transfer, probably due to high protein binding.
• Propofol: may rarely change milk color temporarily to green.
• Local anesthetics: compatible due to low oral bioavailability and low systemic absorption when used in regional techniques.

Benzodiazepines: where caution lies

The article describes a relatively higher risk profile due to prolonged half-life and lipophilicity.

Reports of infant sedation after benzodiazepines occurred almost exclusively when combined with opioids, suggesting a synergistic effect with potentiation of respiratory depression.

Remimazolam is presented as a theoretically promising alternative (esterase metabolism, ultrashort-acting), with potentially lower transfer and faster clearance than midazolam, but without safety data in lactation available at this time.

3.2 Analgesics

Many mothers avoid analgesics out of fear of harming the baby; the article describes how this "silent suffering" can hinder breastfeeding success, as pain can interfere with bonding, positioning, lead to increased stress/anxiety, and potentially impact production.

Recommended strategy

Prioritize non-opioids as first-line therapy and reserve opioids for rescue, limiting risks while maintaining adequate analgesia.

Acetaminophen and NSAIDs are described as safe, with doses in milk below the therapeutic doses administered directly to infants.

Opioids: what the article highlights

• Oxycodone: updated FDA labeling; oral doses up to 60 mg/day were considered compatible in most clinical scenarios (limit to ≤60 mg/day due to accumulation of the metabolite oxymorphone).
• Codeine and tramadol: despite reassessments of classic cases, the FDA safety communication recommending avoidance in breastfeeding women remains unchanged.
• Meperidine: should be avoided because it generates normeperidine (half-life 15-30 h), with accumulation, transfer to milk, and neuroexcitatory potential in infants with immature hepatic clearance. For post-anesthetic shivering, the article suggests compatible alternatives: active cutaneous warming combined with ketamine, magnesium, dexmedetomidine, or fentanyl, although a single dose of meperidine appears safe.

Table 2. Analgesics during lactation (article summary)

3.3 Antiemetics

Postoperative nausea and vomiting are particularly relevant because they can prolong recovery and hospital stay, reduce oral intake/hydration, and worsen the experience, with expected impact on the lactation plan; therefore, prophylaxis is considered prudent.

Table 3. Antiemetics during lactation (according to the article)

3.4 Other perioperative drugs (useful points)

• Neuromuscular blocking agents (NDMRs): despite the absence of specific studies on milk, rocuronium/vecuronium/cisatracurium have predictable redistribution/elimination and clinically insignificant plasma levels when the patient regains consciousness and can breastfeed.
• Sugammadex: used in cesarean sections since 2015 without documented adverse effects in infants; considered compatible despite limited transfer data.
• Vasopressors (phenylephrine/ephedrine/epinephrine/norepinephrine): extremely short half-life and rapid metabolism; even traces in milk would have bioavailability eliminated by first-pass metabolism. Breastfeeding can be resumed when the mother is conscious and hemodynamically stable.
• Antiseptics: chlorhexidine on intact skin has minimal risk due to low systemic absorption; however, iodine-based preparations warrant caution because the mammary gland expresses the sodium-iodide symporter (NIS), creating an active accumulation pathway into milk. When applied to mucous membranes during mature milk production, there may be significant maternal absorption and transfer to milk, with potential for excessive exposure and theoretical risk of thyroid dysfunction in the infant (neonates are particularly sensitive). Prefer non-iodinated alternatives when feasible and when systemic absorption is expected.

4) Anesthetic management of the lactating patient: pre-, intra-, and postoperative roadmap#

4.1 Preoperative: standardize the assessment

The article recommends incorporating lactation status as part of the routine pre-anesthetic evaluation in women of childbearing age.

The assessment should be practical and focused on the real risk of interruption:

• Patient's goals for the perioperative and postoperative period.
• Current health of the infant.
• Time of last breast emptying and established pattern (frequency and maximum interval).
• Nutritional significance of milk in the diet and "lactation scenario" (whether exclusive breastfeeding or supplementary to an already introduced diet).
• Familiarity with a breast pump and equipment availability; some patients do not routinely express and may need support.

Logistical planning should include a realistic estimate of total separation time (pre → procedure → recovery until awake and alert) and discussion of intraoperative expression (by a trained professional) if separation may exceed the longest usual interval between feedings.

The article also suggests considering institutional lactation support capacity as a possible reason for transfer when clinically pertinent.

4.2 Intraoperative

Medication selection

Select effective and compatible medications following the standard of care; when there is a compatibility concern, consider appropriate therapeutic alternatives.

The article draws attention not only to drugs that may produce effects in the infant but also to those that may affect production (e.g., antiemetics) even without direct risk to the infant.

When possible, weigh risks and benefits with the patient.

Intraoperative expression (when to indicate)

Expression should follow the usual frequency (direct feeding or pump).

If the time from the preoperative period until the patient is awake and alert is equal to or greater than the longest usual interval, discuss and offer intraoperative expression.

Intraoperative expression requires an experienced team and access planning according to surgical position; under general anesthesia, expressed milk is not saved.

Positioning, fluids, and rapid recovery

Avoid pressure on the breasts Full breasts are more susceptible to trauma and may increase the risk of mastitis; consider a wireless bra if compatible.

Fluids Goal of euvolemia with slightly higher maintenance requirements (200-500 mL/day), but avoid overload due to the risk of "third space" expansion in breast tissue and compression of milk ducts.

Clear liquids should be encouraged until thirst is quenched when appropriate.

Recovery Since the resumption of breastfeeding depends mainly on the patient's mental state/alertness, pain, nausea, and the need for additional sedation should be minimized; multimodal analgesia, nausea prophylaxis, and regional techniques should be part of the plan.

4.3 Postoperative: the practical rule and what to implement

The patient can resume breastfeeding or expression as soon as she is awake and alert; this state indicates sufficiently reduced plasma levels, corresponding to minimal transfer to milk.

This is where the article consolidates "sleep and keep" as a replacement for "pump and dump."

Additionally, the article recommends individualized and consistent support, including resources for maintaining supply, expression techniques, and facilitation of rooming-in when appropriate.

When the infant is present in the hospital, there should be an adult caregiver other than the patient; and caregivers should monitor for changes in behavior, wakefulness, or feeding patterns while the mother receives medications and care.

5) Conclusion: four messages that change practice#

• Awake and alert? She can breastfeed/express without discarding.
• Milk supply depends on removal: plan logistics so as not to exceed the longest usual interval; if necessary, consider intraoperative expression.
• Analgesia is part of successful breastfeeding: scheduled non-opioids + opioid for rescue; avoid codeine, tramadol, and repeated doses of meperidine.
• Choose drugs by efficacy and compatibility, not by fear: the majority of perioperative medications are compatible with uninterrupted lactation.