Part 35 (1/2)

NA.

Marijuana

Methadone +.

Methamphetamine (+).

Morphine (+).

PCP.

Tobacco +.

NA.

Ts and Bluesa (+).

Clinical evaluation CNS, central nervous system; ICH, intracranial hemorrhage; LSD, lysergic acid diethylamide; PCP, phencyclidine.

+, Doc.u.mented, positive; , doc.u.mented, negative; () data inconclusive but suggestive of a negative finding; (+) data inconclusive but suggestive of a positive finding; ?

unknown; NA, not applicable/not available.

aInfarction/embolism.

Modified from Little et al., 1990b.

299.

300.

Substance abuse during pregnancy confidential. In the USA, these records are protected by Federal Law (CFR 37). The author's spouse is an attorney, and states that no release should ever be signed and that each person must protect their individual rights to privacy a.s.sertively.

Another important aspect of patient consultation is to provide information regarding specific risks from substance use (Tables 16.1 and 16.2). It is important that this information be as accurate as possible. 'Scare' tactics or exaggeration-type deterrents should be avoided because substance users are aware of this commonly employed approach and trust in the physician and his/her credibility will be eroded. The most ethical and legally sound approach is to provide information that may be verified directly with the medical literature. We currently use a standardized summary generated from a computerized database [Teratogen Information System (TERIS), see Chapter 1] for this information. The TERIS summaries are more detailed than this book's chapters and are very well doc.u.mented.

Ultimately, the clinical conclusion/treatment is that social and illicit substance use during pregnancy is contraindicated because of the a.s.sociated maternal and embryo fetal risks.

The need for services to a.s.sist pregnant substance users is being recognized, and programs exist in most areas. For a.s.sistance in locating such a treatment program, the physician can contact their local substance abuse service, or their state's commission on substance abuse that accredits treatment facilities. Ideally, the pregnant substance user should be managed by the obstetrician in conjunction with a program designed to promote abstinence or at least to reduce the substance use during pregnancy. The medical positions of abstinence and treatment are the only appropriate ones clinically and legally.

Patient evaluation Note: Use of 'legal, legally, etc.' is not intended as a subst.i.tution for legal advice and the reader is cautioned to contact a licenced attorney when confronted with questions concerning issues of the law and its application in the situation confronted, as noted in Chapter 1. Laws vary from state to state and from nation to nation. One's medical malpractice insurance provider is often the most economical and efficient source of legal information as this service is often included as a provision of a medical malpractice policy.

The pregnant substance user should be considered a high-risk obstetric patient.

Pregnant substance users are at increased risk for a number of complications, including s.e.xually transmitted diseases (STDs), hepat.i.tis, poor nutrition, and bacterial endocarditis. With the exception of tobacco and marijuana, chronic use of the substances reviewed in this chapters is an indication for syphilis, gonorrhea, herpes, chlamydia, HIV, and hepat.i.tis testing. Women who use drugs administered by the parenteral route are at greatest risk not only for HIV but also for other STDs, including hepat.i.tis. Drug injection sites on the upper forearm ('track marks') are strong evidence of a serious substance use problem, but this is not frequently observed. Among 122 gravid parenteral substance users (intravenous drug abusers, IVDAs), only one woman presented with track marks on the forearm. The other 121 IVDA women used hidden sites of injection (veins in b.r.e.a.s.t.s, thighs, calves, and ankles) (Little et al et al., 1990b).

Substances of abuse usually have an anorectic effect and often result in poor weight gain during pregnancy. Other possible signs of substance use during pregnancy include new-onset 'spontaneously arising' heart murmur and hypertension not a.s.sociated with preeclampsia. Heart murmurs occur with increased frequency among women who are Clinical evaluation Clinical evaluation 301.

chronic substance users. Heart murmurs also occur in a.s.sociation with bacterial endocarditis or a history of this disease. Chronic substance use can induce hypertension in the nonpregnant adult, although not all have been studied for hypertensive effects during pregnancy. Cocaine, heroin, and tobacco use is known to be a.s.sociated with hypertension during pregnancy (Abel, 1980a,b; Little et al et al., 1989b, 1990a; Stillman et al et al., 1986). In addition, abruptio placentae or a history of this serious complication is also an indication that substance use may be a factor. Risk of abruptio placentae may be as high as 12 percent among substance abusers compared to 0.1 percent (one in 830) in the general population (Cunningham et al et al., 1997). Stillbirths are increased in frequency with substance use during pregnancy. A history of stillbirths may, along with other risk factors, be a clue to the obstetrician that substance abuse is a complicating factor.

Hidden risks of substance abuse: impurities All substances of abuse, even alcohol, may be contaminated by certain impurities.

'Moons.h.i.+ne' (illegally distilled alcohol) can contain significant amounts of lead and cause heavy metal poisoning in the mother and fetus. Amphetamine and methamphetamines may contain impurities, such as lead oxides (Allcott et al et al., 1987). Leaded gasoline is sometimes used as the solvent, resulting in lead contamination in the extraction of cocaine paste from cocoa leaves. Production of illicit drugs, such as PCP, involve cyanohydrin intermediate reactions. If not fully reacted, cyanide may be contained in the final product because illicit laboratories are usually crudely equipped for purification, with no quality control. Lead and cyanide poisoning have resulted from the use of illicitly manufactured substances and are a.s.sociated with significant maternalfetal morbidity and mortality. In the manufacture of LSD, incomplete amination of lysergic acid or failure to purify the product, will result in lysergic acid toxicity (peripheral neuropathy and progressive necrosis) in humans and animals (Rall and Schleifer, 1985). Drugs available as tablets or capsules (for example, codeine, methadone, morphine, benzodiazepines, pentazocine) contain a significant amount of the tablet/capsule vehicle agent (usually more than 97 percent), typically microcrystalline cellulose. When prepared for parenteral use by the IVDA, the substance is frequently dissolved in water with no attempt to separate the drug from the vehicle, resulting in a very high potential for pulmonary emboli, placental infarcts, and other maternal vascular blockages.

Inhalants are aromatic (benzene ring-containing) substances, such as toluene or gasoline, that may also contain lead or nitriles that can cause toxicity. Even marijuana may contain dangerous vegetable contaminants such as nightshade, poison sumac, poison ivy, and poison oak, all of which may cause serious pulmonary-cardiac morbidity or even death when smoked. In addition, herbicides (e.g., paraquat) and/or pesticides (i.e., chlor-dane) may be contained in the marijuana itself as a result of treatment during the plant's growth, since there is no quality control of production practices (Klaa.s.sen, 1985). Death may also be a.s.sociated with smoking marijuana contaminated with herbicides.

Other drugs and chemicals as dilutants Other substances are used by dealers to 'cut' or dilute illicit drugs to increase their profits. Sometimes the dilutant is more dangerous than the illicit drug. Cocaine is cut with lidocaine, amphetamines, and sometimes fine gla.s.s beads. Amphetamines are diluted, 302 302 Substance abuse during pregnancy sometimes heavily, with certain antihistamines or ephedrine. Heroin is known to have been cut with diverse compounds: talc.u.m, confectioner's sugar, and even finely ground sawdust. Perhaps the most notorious case of the dilutant being more dangerous than the substance of abuse is cutting heroin with warfarin, leading to a cl.u.s.ter of warfarin embryopathy cases that were never published. Some of these dilutants were teratogenic and these and others may cause serious maternal and/or placental complications, especially when used parenterally. Strychnine and a.r.s.enic have been intentionally added to amphetamine, methamphetamine, cocaine, heroin, and LSD to intensify their effects, although the 'intensification' is actually due to subclinical strychnine/a.r.s.enic toxicity.