14 OBSTETRICS OCTOBER 2011 • OB.GYN. NEWS DRUGS, PREGNANCY, AND LACTATION Anesthetic Agents ocal and general anesthetic agents low absorption suggests that it is safe. but the human pregnancy experience is ei- posed children had significantly lower are commonly used in pregnancy, Benzocaine and pramoxine are available ther absent or very limited. Moreover, the gross motor ability and more evidence of Lespecially for epidural or combined in OTC preparations for anorectal indica- animal reproduction data, when these inattention/hyperactivity. Moreover, the spinal epidural analgesia at delivery. tions, such as hemorrhoids. The human agents were used alone, were reassuring. level of exposure was significantly and Although surgery requiring general anes- pregnancy data are limited, but because Because nitrous oxide is a gas, con- negatively correlated with fine motor thesia is less common, such use is still there are more than 50 such products and cerns have been raised about the poten- ability and IQ performance (Birth Defects relatively frequent. hemorrhoids are common in tial for adverse effects on the embryo-fe- Res. A. Clin. Mol. Teratol. 2004;70:476- Local anesthetics are given pregnancy, these agents appear tus, as well as the potential effects on 82). This study supported the hypothesis by injection or topically, and to be widely used in pregnan- women of reproductive potential work- that occupational exposure to waste anes- include benzocaine, bupiva- cy. Systemic absorption may ing in surgical areas. Moreover, when thetic gases during pregnancy might be a caine (Marcaine, Sensorcaine), occur from mucous mem- used for surgery, nitrous oxide is always risk factor for minor neurological deficits chloroprocaine (Nesacaine), branes or from damaged skin combined with other general anesthetic in the offspring. Although more data are camphor, dibucaine (Nuper- with the amount absorbed agents. In animals, the gas is an embryo- needed, women of reproductive potential cainal), levobupivacaine (Chi- dependent on the dose. fetal toxin (growth restriction, structural working in surgical areas should consid- rocaine), lidocaine (Xylocaine, The local anesthetics avail- anomalies, and death), but the maternal er decreasing or eliminating their expo- Octocaine), mepivacaine (Car- able for ophthalmic use are exposures were sometimes high and pro- sure to anesthetic gases if pregnancy is a bocaine, Polocaine), pramox- lidocaine (Akten), propara- longed. Long-lasting effects reported in possibility. Moreover, postponing elective ine, prilocaine (Citanest), pro- GERALD G. caine (Alcaine, Ophthetic, animals include permanent brain damage surgery until after pregnancy or, at least, BRIGGS, caine (Novocaine), ropivacaine B.PHARM., FCCP Paracaine), proparacaine com- resulting in abnormal behavior effects in after the period of organogenesis, also (Naropin), and tetracaine bined with fluorescein (Flu- motor development and general activity. should be considered. Pregnancy tests (Pontocaine). For neuraxial analgesia, low caine, Fluoracaine, Flurate, Fluress, In humans, reports have described should be conducted in any woman of doses of bupivacaine, lidocaine, or ropi- Flurox), and tetracaine (Altacaine, spontaneous abortions, infertility, and reproductive potential before surgery. vacaine – with or without a small dose of Tetcaine). decreased birth weight in exposed preg- Although the data are very limited, small an opioid such as fentanyl – are common- In the above situations, with the excep- nancies and in women of reproductive amounts of some local anesthetics such as ly used. Use of injectable anesthetics for tion of cocaine, the risk of any aspect of potential working in surgical areas and lidocaine are excreted into breast milk. dental procedures also is common in preg- developmental toxicity from appropriate dental offices. Many of these retrospec- Because the amounts in the maternal cir- nancy. Maternal toxicity involving the cen- doses and administration of local anes- tive reports were subject to self-reporting culation are usually very low, any exposure tral nervous and cardiovascular systems thetics appears to be rare or nonexistent. and/or recall bias, as well as confounders of a nursing infant probably is clinically may result from inadvertent intravenous General anesthetics can be classified as such as lack of information on exposure insignificant. Mothers exposed to general administration or excessive doses. injectable, gases, or volatile liquids. The in- dose, type of anesthesia, use of other anesthetics will not be capable of nursing Topical anesthetics are commonly jectable agents include droperidol (Inap- drugs, maternal age, and smoking. Scav- for several hours, thus allowing clearance used in dermatologic products; many sine), etomidate (Amidate), fospropofol enging and ventilating surgical rooms of the agents from their circulation. ■ are over-the-counter (OTC) products (Lusedra), ketamine (Ketalar), metho- will lessen the exposure of personnel, with multiple trade names not listed hexital (Brevital), midazolam (Versed), but will not completely free the area of MR. BRIGGS is a pharmacist clinical here. Such agents include benzocaine, propofol (Diprivan), and sodium thiopen- waste gases. Fortunately, the data do not specialist, Outpatient Clinics, Memorial butamben, cocaine, dibucaine, lidocaine, tal (Pentothal). The volatile liquids in- support an association between acute Care Center for Women at Miller Children’s pramoxine, prilocaine, tetracaine, and clude desflurane (Suprane), enflurane or chronic nitrous oxide exposure and Hospital in Long Beach, Calif.; a clinical dyclonine (a bactericidal and fungicidal (Ethrane), halothane (Fluothane), iso- structural anomalies, but the news for professor of pharmacy at the University of local anesthetic used in lozenges and flurane (Forane), methoxyflurane neurotoxicity is troubling. California, San Francisco; and an adjunct throat sprays for sore throats). The three (Penthrane), and sevoflurane (Ultane). All A 2004 study compared 40 children professor of pharmacy at the University of topical cocaine products are controlled of the agents in these two categories of (ages 5-13 years) born to female physicians Southern California, Los Angeles. He also is substances. Because of rapid absorption general anesthetics have the potential to and nurses who were exposed to waste a fellow of the American College of Clinical that can produce toxicity in the user, they cause neonatal depression or adverse neu- anesthetic gases (specific agents not iden- Pharmacy, coauthor of “Drugs in Pregnancy are best avoided in pregnancy. Ethyl chlo- robehavioral effects if used close to birth. tified) with 40 nonexposed controls and Lactation,” and coeditor of “Diseases, ride (chloroethane) is a refrigerant used For most agents, developmental toxicity matched for age, gender, and maternal oc- Complications, and Drug Therapy in as a topical anesthetic. Although there during other periods of gestation, includ- cupation. The developmental milestones Obstetrics.” He had no disclosures related to are no reports of its use in pregnancy, the ing organogenesis, has not been reported, in the two groups were similar, but the ex- the topic of this article. Simulator Teaches Force Modulation for Shoulder Dystocia BY M. ALEXANDER OTTO Major Finding: Following training on a birth simulator, the then 100 N several times, to get a force-monitoring screen. “We feel for what those levels of force plummeted the heart rate and FROM THE ANNUAL RESEARCH percentage of clinicians pulling with more than 150 N during MEETING OF ACADEMYHEALTH simulated shoulder dystocia deliveries fell from 75% to 43%. felt like. At 100 N, Dr. Guise told tried to get everything as realistic Data Source: A nonrandomized educational intervention them, “this is the most you should as it could be. The actress was SEATTLE – Use of a birth force VITALS involving 40 clinicians. ever feel, so pay attention” to really acting it up,” she said. simulator taught clinicians better Disclosures: Dr. Guise said she had no relevant financial what it feels like: “If you’re start- Even under pressure, training how to modulate how much disclosures. The project was funded by the Agency for ing to shake, how your facial made a significant difference. Al- force they use when handling a Healthcare Research and Quality (AHRQ). muscles feel,” and so on. though 33 (82%) of the partici- case of shoulder dystocia to avoid To see if the training took, pants used more than 100 N, brachial plexus and other injuries. participants went through sur- only 17 (43%) used more than The pull should be no more emergencies are not very teach- with force monitoring, made by prise simulations. During their 150 N, and 11 (28%) used more than 100 newtons (N), a gentle able moments. Dr. Guise and her Limbs & Things Ltd. (Bristol, shifts, a nurse came running up than 200 N. “There was a reduc- but firm traction, according to colleagues wanted to see if train- England). Initially, they were saying, “I need a doctor, I need a tion in overall forces applied after Dr. Jeanne-Marie Guise, an ob- ing on a birth simulator would blinded to the force-monitoring doctor!” Trainees were pulled simulation training. Participants stetrician and gynecologist at help clinicians get a feel for how screen; 38 (95%) pulled with into a triage room, “but didn’t ex- were able to gauge forces ap- Oregon Health and Science Uni- much force to use. more than 100 N, 30 (75%) with actly know why,” Dr. Guise said. plied after