Acute obtundation in a 9-month-old patient: ethanol ingestion.

Alcohol ingestion in the pediatric patient can be life threatening. Younger patients consume larger volumes per body weight with accidental ingestions, and children have more serious adverse effects at lower blood alcohol levels. Complications of alcohol poisoning can include hypothermia, hypoglycemia, seizures, coma, and death. We present the course of a 9-month-old female infant who became unresponsive at home and presented to the emergency department comatose. When her blood alcohol level registered 489 mg/dL, it was revealed that she had accidentally been given a bottle of formula mixed with vodka rather than water. The infant required intubation for severely depressed level of consciousness and aggressive fluid resuscitation for hemodynamic instability. She had a peak lactate level of 24 mmol/L and a peak blood alcohol level of 524 mg/dL. Based on the severity of her initial presentation, preparations were made for hemodialysis. The infant responded to supportive measures including mechanical ventilation, fluids, and dextrose, and hemodialysis was not necessary. Her alcohol clearance followed zero-order kinetics at an average rate of 28.6 mg/dL per hour over 15.5 hours from her peak level of 524 mg/dL to the lowest measured value of 80 mg/dL. The kinetics of ethanol clearance at this level of toxicity, which is the highest reported in an infant to date, enhance our knowledge of ethanol metabolism and will assist in management decisions in cases of severe intoxication.

Breath alcohol estimation training: behavioral effects and predictors of success.

AIMS: Breath alcohol concentration (BrAC) estimation training has been effective in increasing estimation accuracy in social drinkers. Predictors of estimation accuracy may identify populations to target for training, yet potential predictors typically are not evaluated. In addition, the therapeutic efficacy of estimation training as a preventive strategy for problematic drinking is unknown. METHODS: Forty-six social drinkers with a recent binge history were randomly assigned to an intervention or control group (n = 23 per group). In each of three sessions (pretraining, training, testing), participants consumed alcohol (0.32, 0.24, 0.16 and 0.08 g/kg, in random order) every 30 min (total dose: 0.8 g/kg). Participants provided five BrAC estimates within 3 h of alcohol administration. The intervention group, but not control group, received internal and external training. During testing, participants provided BrAC estimates, but received no feedback. Participants returned for two follow-up visits to complete self-report measures. RESULTS: BrAC estimation training improved intervention group estimation accuracy within the laboratory. Together, training, low trait anxiety and low risk expectancy predicted high testing accuracy. There were no significant group differences in subsequent alcohol consumption, behavior under the influence or risk expectancy regarding potentially hazardous behaviors. CONCLUSION: BrAC estimation training is effective in the laboratory but may not translate into naturalistic settings.

Rapid drinking is associated with increases in driving-related risk-taking.

OBJECTIVE: The rate of alcohol drinking has been shown to predict impairment on cognitive and behavioral tasks. The current study assessed the influence of speed of alcohol consumption within a laboratory-administered binge on self-reported attitudes toward driving and simulated driving ability. METHOD: Forty moderate drinkers (20 female, 20 male) were recruited from the local community via advertisements for individuals who drank alcohol at least once per month. The equivalent of four standard alcohol drinks was consumed at the participant's desired pace within 2-h session. RESULTS: Correlation analyses revealed that, after alcohol drinking, mean simulated driving speed, time in excess of speed limit, collisions, and reported confidence in driving were all associated with rapid alcohol drinking. CONCLUSION: Fast drinking may coincide with increased driving confidence because of the extended latency between the conclusion of drinking and the commencement of driving. However, this latency did not reduce alcohol-related driving impairment, as fast drinking was also associated with risky driving.

Cognitive, psychomotor and polysomnographic effects of trazodone in primary insomniacs.

Trazodone is prescribed widely as a sleep aid, although it is indicated for depression, not insomnia. Its daytime cognitive and psychomotor effects have not been investigated systematically in insomniacs. The primary goal of this study was to quantify, in primary insomniacs, the hypnotic efficacy of trazodone and subsequent daytime impairments. Sixteen primary insomniacs (mean age 44 years) participated, with insomnia confirmed by overnight polysomnography (sleep efficiency ≤ 85%). Trazodone 50 mg was administered to participants 30 min before bedtime for 7 days in a 3-week, within-subjects, randomized, double-blind, placebo-controlled design. Subjective effects, equilibrium (anterior/posterior body sway), short-term memory, verbal learning, simulated driving and muscle endurance were assessed the morning after days 1 and 7 of drug administration. Sleep was evaluated with overnight polysomnography and modified Multiple Sleep Latency Tests (MSLT) on days 1 and 7. Trazodone produced small but significant impairments of short-term memory, verbal learning, equilibrium and arm muscle endurance across time-points. Relative to placebo across test days, trazodone was associated with fewer night-time awakenings, minutes of Stage 1 sleep and self-reports of difficulty sleeping. On day 7 only, slow wave sleep was greater and objective measures of daytime sleepiness lower with trazodone than with placebo. Although trazodone is efficacious for sleep maintenance difficulties, its associated cognitive and motor impairments may provide a modest caveat to health-care providers.

Alcohol effects on simulated driving in frequent and infrequent binge drinkers.

OBJECTIVE: Compared with non­bingers, binge drinkers are more likely to drive while intoxicated. The extent to which binge frequency impacts confidence in driving and subsequent driving impairment is unknown. This study compared the effects of an experimenter­delivered alcohol binge on subjective impairment and simulated driving ability in female high­frequency and low­frequency bingers. METHODS: Female drinkers were assigned to high­frequency (n = 30) or low­frequency (n = 30) binge groups based on their Alcohol Use Questionnaire responses. At 30­min intervals within a 2­h period, participants received either a placebo drink (n = 15 per group) or a 0.2 g/kg dose of alcohol (n = 15 per group; cumulative dose 0.8 g/kg). Self­reported impairment, driving confidence, and simulated driving were then measured. RESULTS: Self­reported confidence in driving was significantly lower after alcohol than after placebo in low­frequency but not highfrequency bingers. Self­reported impairment and collisions during simulated driving were significantly greater after alcohol than after placebo in both low­frequency and high­frequency bingers. CONCLUSIONS: The impairing effects of a single alcohol binge on driving ability in women are not influenced by binge frequency. However, high binge frequency may be associated with a less cautious approach to post­binge driving.

Response inhibition impairments predict alcohol-induced sedation.

AIMS: The aim of this study was to probe the relationship between the subjective effects of alcohol and impulsive behavior in social drinkers. METHODS: Fifty social drinkers performed a response-inhibition task before consuming alcohol. A 0.8-g/kg dose of alcohol was administered in a binge-like fashion (0.2 g/kg every 30 min) to the participants over a 2-h time period. Participants then completed questionnaires measuring stimulation, sedation and mood following consumption of alcohol. Linear regression analyses were performed by examining the relationship between performance on the response inhibition impulsivity task and subjective responses to alcohol (i.e. stimulation, sedation and arousal). RESULTS: There was a significant positive relationship found between impulsive responding and self-reported sedation following alcohol consumption. Additionally, there was a significant negative relationship between behavioral impulsivity and self-reported stimulation and arousal following alcohol consumption. CONCLUSION: These results suggest that higher levels of impulsivity are associated with experiencing greater sedating than stimulating effects of alcohol. Individuals with high levels of impulsivity may be less sensitive to the stimulating effects of a specified dose of alcohol, which could lead to these individuals consuming more alcohol to experience the stimulating effects of alcohol.

Tanning as an addictive behavior: a literature review.

BACKGROUND: Recent studies have identified reinforcing properties associated with tanning and suggest a possible physiologic mechanism and addiction driving tanning behavior. OBJECTIVE: This article attempts to synthesize the existing literature on tanning and addiction to investigate possible associations. METHODS: We investigated a variety of substance dependence models to define what constitutes dependence/addiction and to determine how current studies on tanning meet these criteria. RESULTS: In some individuals, tanning has met Diagnostic and Statistical Manual criteria for a substance-related disorder or tanning-modified Cut Down, Annoyed, Guilt, Eye-opener criteria. Trial studies have demonstrated the induction of withdrawal symptoms in frequent tanners. LIMITATIONS: Additional studies are needed to investigate the associated dependency and addiction more fully and to elucidate its similarities to other better-known addictive syndromes. DISCUSSION: Tanning is a problem behavior, both as a health risk and as a possible dependency. Future studies, especially in the area of cognitive mapping and cue-related stimuli are needed. Imaging studies may be important in elucidating whether the same areas of the brain are involved in tanning addiction as in other addictive syndromes.

Teenagers do not always lie: characteristics and correspondence of telephone and in-person reports of adolescent drug use.

Because of the widespread use of drugs by adolescents, there is demand for scientific rigor in sampling and accuracy in methods for ascertaining drug use patterns. The present study: (1) characterized adolescents who responded to advertisements for marijuana users; (2) compared rates of drug use reported on the telephone versus an on-site interview; and (3) examined drug use patterns as a function of parental awareness of drug use. Adolescents, identifying themselves as marijuana users during telephone interviews, reported more use of other drugs than those denying marijuana use. There was a high degree of correspondence between telephone and on-site interviews for all drugs except alcohol, which was reported at a higher rate on-site. Of those reporting marijuana use in the past week, 69% tested positive for marijuana in their urine-drug screens. Finally, marijuana and alcohol use patterns were higher among adolescents whose parents were aware of drug use than those whose parents indicated that their adolescent did not use marijuana. These results indicate that adolescents are willing to self-identify as marijuana users and report drug and alcohol use during telephone interviews. Additionally, parents appear to become more aware of their adolescent's drug use with increased frequency of use.

Induction of withdrawal-like symptoms in a small randomized, controlled trial of opioid blockade in frequent tanners.

Frequent tanning has reinforcing properties. We tested whether opioid antagonism blocks potential reinforcing effect of indoor tanning in 8 frequent tanners and 8 infrequent tanner control subjects. Opioid blockade reduced ultraviolet preference in frequent tanners. Four of 8 frequent tanners, but no infrequent tanners, exhibited withdrawal-like symptoms with naltrexone administration. A limitation of this study is its small size.

Involvement of cholinergic neuronal systems in intravenous cocaine self-administration.

Recent studies suggest the participation of cholinergic neurons in the brain processes underlying reinforcement. The involvement of cholinergic neurons in cocaine self-administration has been recently demonstrated in studies using muscarinic and nicotinic agonists and antagonists, microdialysis, assessment of choline acetyltransferase activity and acetylcholine (ACh) turnover rates. The present experiment was initiated to identify subsets of cholinergic neurons involved in the brain processes that underlie cocaine self-administration by lesioning discrete populations with a selective neurotoxin. Rats were trained to self-administer cocaine and the cholinergic neurotoxin 192-IgG-saporin or vehicle was then bilaterally administered into the posterior nucleus accumbens (NAcc)-ventral pallidum (VP). The 192-IgG-saporin induced lesions resulted in a pattern of drug-intake consistent with either a shift in the dose intake relationship to the left or downward compared to sham-treated controls. A second experiment used a self-administration threshold procedure that demonstrated this lesion shifted the dose intake relationship to the left compared to the sham-vehicle treated rats. The magnitude and extent of the lesion was assessed by measuring the expression of p75 (the target for 192-IgG-saporin) and choline acetyltransferase (ChAT) in the NAcc, VP, caudate nucleus-putamen (CP) and vertical limb of the medial septal nucleus-diagonal band (MS-DB) of these rats using real time reverse transcriptase-polymerase chain reaction. Significant reductions in gene expression for p75 (a selective marker for basal forebrain cholinergic neurons) and ChAT were seen in the MS-DB and VP while only small decreases were seen in the NAcc and CP of the 192-IgG-saporin treated rats. These data indicate that the overall influence of cholinergic neurons in the MS-DB and VP are inhibitory to the processes underlying cocaine self-administration and suggest that agonists directed toward subclasses of cholinergic receptors may have efficacy as pharmacotherapeutic adjuncts for the treatment of cocaine abuse.

Separate and combined effects of marijuana and alcohol on mood, equilibrium and simulated driving.

RATIONALE: Marijuana and alcohol, when used separately and in combination, contribute to automobile accidents and failed sobriety tests of standing balance. However, the extent to which the drugs have additive effects on both of these measures is unknown. OBJECTIVES: This study was designed to compare directly the separate and combined effects of marijuana and alcohol on simulated emergency braking and dynamic posturography. METHODS: Twelve healthy subjects who regularly used both marijuana and alcohol completed nine test sessions in a counterbalanced within-subject design. Subjects drank a beverage (0, 0.25, or 0.5 g/kg alcohol) then smoked a cigarette (0, 1.75, or 3.33% THC). Testing began 2 min after smoking and was conducted within the ascending limb of the blood alcohol curve. RESULTS: The 0.5 g/kg alcohol dose significantly increased brake latency without affecting body sway. In contrast, the 3.3% THC dose increased body sway but did not affect brake latency. There were no additive drug effects on mood or behavior. CONCLUSIONS: Although field sobriety tests are often used to determine driving impairment, these results suggest that impaired balance following marijuana use may not coincide with slowed reaction time. Conversely, braking impairment from low doses of alcohol may not be revealed by tests of balance.

Behavioral and subjective effects of marijuana following partial sleep deprivation.

This study tested whether performance would be more impaired when marijuana use followed partial sleep deprivation (PSD) than when marijuana use followed a typical night of sleep. Seven recreational marijuana users (mean 15 of last 30 days) completed six test sessions in a double-blind randomized within-subject design. Each session began with an overnight stay in a sleep laboratory. Bed and wake times were calculated from mean data on individual sleep diaries. Time-in-bed was either regular (mean=8.2 h) or shortened (first 65% of regular time-in-bed deprived). At 3 and 5 h after waking, daytime sleepiness was measured with self-report questionnaires and a sleep latency test. Approximately 6.5 h after waking, subjects smoked a marijuana cigarette (0.003, 2, or 3.5% delta-9 tetrahydrocannabinol [THC]). Test batteries were completed 2, 62, and 122 min after smoking ended. Sleepiness was significantly greater following PSD than after regular sleep. Following regular sleep, heart rate increases with active THC doses were comparable, but heart rate with 2% THC was significantly less elevated following PSD. Ratings of "impaired" and "stoned" increased with both THC doses after regular sleep and were further increased with 3.5% THC after PSD. High-potency marijuana increased body sway similarly across sleep conditions. There were no significant effects of marijuana or PSD, alone or in combination, on brake latency. Thus, while PSD increased the dose-dependence of THC effects on heart rate and subjective impairment, it did not enhance the effects of marijuana on standing balance and brake latency.

Long-term heavy marijuana users make costly decisions on a gambling task.

RATIONALE: Chronic marijuana use has been associated with impairments of learning, memory, and executive functions. Little is known, however, about the effects of marijuana use on other cognitive domains, such as decision-making, which are thought to play an important role in addiction and drug abuse. OBJECTIVES: The purpose of the present study was to determine if long-term heavy marijuana users employ different decision-making strategies than individuals with minimal marijuana exposure. METHODS: Volunteers were assigned to a cannabis (n = 10) or control group (n = 10) based upon history of prior marijuana use. Demographic and neuropsychological variables were evaluated, and a decision-making task--the gambling task (GT) was administered. RESULTS: Although few demographic and neuropsychological differences were noted between groups, marijuana users made more decisions that led to larger immediate gains despite more costly losses than controls. CONCLUSIONS: These data suggest that long-term heavy marijuana users may have specific deficits in the ability to balance rewards and punishments that may contribute to continued drug-taking behavior. It is unknown, however, whether the basis for such deficits might be attributed directly to marijuana exposure or pre-existing genetic or behavioral differences.

Ultraviolet exposure is a reinforcing stimulus in frequent indoor tanners.

BACKGROUND: Investigations into tanners' reasons for tanning have focused primarily on the perception of improved appearance. Reported relaxing effects of tanning suggest the possibility of a physiologic effect of UV that drives tanning behavior. OBJECTIVE: We sought to determine if there is a physiologic reinforcing effect of UV exposure, separate from appearance motivation, that may contribute to tanning behavior. METHODS: We determined the reinforcing effect of UV light in a series of controlled, blinded, repeated-choice trials of UV carefully designed to separate as cleanly as possible reinforcing effects of UV exposure from other factors including perceived benefits of having a tan. A total of 14 young adults who used tanning beds regularly were exposed to otherwise identical UV and non-UV tanning bed stimuli on Mondays and Wednesdays for 6 weeks. On Fridays, participants had concurrent access to the two beds. The primary dependent variable was the percentage of choice sessions during which more UV than non-UV tanning was chosen. RESULTS: In all, 12 participants chose additional tanning exposure on Fridays and, of these, 11 consistently used the UV bed for that exposure. Of the total 41 occasions when participants chose to tan on Friday, 39 sessions (95%) were for the UV bed and only two for the non-UV bed. A more relaxed and less tense mood was reported after UV exposure compared with after non-UV exposure (P=.008 and P=.002, respectively). DISCUSSION: When exposed to UV and non-UV under blinded conditions, frequent tanners can distinguish the two conditions and undertake further UV exposure, indicating that UV is a reinforcing stimulus. The relaxing and reinforcing effects of UV exposure contribute to tanning behavior in frequent tanners and should be explored in greater detail.

Concordance of different measures of nicotine dependence: two pilot studies.

Two samples of adult daily smokers completed a structured interview to determine nicotine dependence according to generic (DSM-IV/ICD-10), Fagerström [Fagerström Tolerance Questionnaire (FTQ), Fagerström Test for Nicotine Dependence (FTND), Heavy Smoking Index (HSI), and time to first cigarette after awakening (TFC)], consumption [e.g., cigarettes/day (CPD)], and self-rating (e.g., "how addicted are you") measures. One sample was a population-based sample of 43 smokers from the Vermont site of the DSM-IV field trial for substance use disorders. The other sample consisted of 50 smokers evenly distributed across a wide range of CPD to study biochemical markers of smokers. In the first study, DSM/ICD criteria were only slightly correlated with Fagerström (r =.24-.35) and consumption (r =.06-0.33) criteria. Self-rating criteria were correlated moderately with most other criteria (r =.24-.60). In the second study, generic, Fagerström, and self-rating criteria increased with increasing CPD up to 30 CPD but not thereafter. One interpretation of these results is that generic, Fagerström, consumption, and self-rating criteria each tap different aspects of nicotine dependence.

Anxiety, sedation, and simulated driving in binge drinkers.

The current study evaluated the relationships among trait anxiety, subjective response to alcohol, and simulated driving following a simulated alcohol binge. Sixty drinkers with a binge history completed the State Trait Anxiety Inventory (STAI), the Alcohol Use Questionnaire, and subsequently completed a driving simulation. Participants were then administered 0.2 g/kg ethanol at 30-min intervals (cumulative dose 0.8 g/kg). Following alcohol consumption, the Biphasic Alcohol Effects Scale (BAES) and visual analog scales of subjective impairment and driving confidence were administered, after which simulated driving was reassessed. Due to the emphasis on simulated driving after drinking in the current study, subjective response to alcohol (i.e., self-reported sedation, stimulation, impairment, and confidence in driving ability) was assessed once following alcohol consumption, as this is the time when drinkers tend to make decisions regarding legal driving ability. Alcohol increased driving speed, speeding tickets, and collisions. Sedation following alcohol predicted increased subjective impairment and decreased driving confidence. Subjective impairment was not predicted by sensitivity to stimulation or trait anxiety. High trait anxiety predicted low driving confidence after drinking and this relationship was mediated by sedation. Increased speed after alcohol was predicted by sedation, but not by trait anxiety or stimulation. Anxiety, combined with the sedating effects of alcohol, may indicate when consumption should cease. However, once driving is initiated, sensitivity to sedation following alcohol consumption is positively related to simulated driving speed.

Self-estimation of blood alcohol concentration: a review.

This article reviews the history of blood alcohol concentration (BAC) estimation training, which trains drinkers to discriminate distinct BAC levels and thus avoid excessive alcohol consumption. BAC estimation training typically combines education concerning alcohol metabolism with attention to subjective internal cues associated with specific concentrations. Estimation training was originally conceived as a component of controlled drinking programs. However, dependent drinkers were unsuccessful in BAC estimation, likely due to extreme tolerance. In contrast, moderate drinkers successfully acquired this ability. A subsequent line of research translated laboratory estimation studies to naturalistic settings by studying large samples of drinkers in their preferred drinking environments. Thus far, naturalistic studies have provided mixed results regarding the most effective form of BAC feedback. BAC estimation training is important because it imparts an ability to perceive individualized impairment that may be present below the legal limit for driving. Consequently, the training can be a useful component for moderate drinkers in drunk driving prevention programs.

Impulsivity, attention, memory, and decision-making among adolescent marijuana users.

RATIONALE: Marijuana is a popular drug of abuse among adolescents, and they may be uniquely vulnerable to resulting cognitive and behavioral impairments. Previous studies have found impairments among adolescent marijuana users. However, the majority of this research has examined measures individually rather than multiple domains in a single cohesive analysis. This study used a logistic regression model that combines performance on a range of tasks to identify which measures were most altered among adolescent marijuana users. OBJECTIVES: The purpose of this research was to determine unique associations between adolescent marijuana use and performances on multiple cognitive and behavioral domains (attention, memory, decision-making, and impulsivity) in 14- to 17-year-olds while simultaneously controlling for performances across the measures to determine which measures most strongly distinguish marijuana users from nonusers. METHODS: Marijuana-using adolescents (n = 45) and controls (n = 48) were tested. Logistic regression analyses were conducted to test for: (1) differences between marijuana users and nonusers on each measure, (2) associations between marijuana use and each measure after controlling for the other measures, and (3) the degree to which (1) and (2) together elucidated differences among marijuana users and nonusers. RESULTS: Of all the cognitive and behavioral domains tested, impaired short-term recall memory and consequence sensitivity impulsivity were associated with marijuana use after controlling for performances across all measures. CONCLUSIONS: This study extends previous findings by identifying cognitive and behavioral impairments most strongly associated with adolescent marijuana users. These specific deficits are potential targets of intervention for this at-risk population.

Failure to sustain prepulse inhibition in adolescent marijuana users.

BACKGROUND: Marijuana use is typically initiated during adolescence, which is a critical period for neural development. Studies have reported reductions in prepulse inhibition (PPI) among adults who use marijuana chronically, although no human studies have been conducted during the critical adolescent period. METHODS: This study tested PPI of acoustic startle among adolescents who were either frequent marijuana users or naïve to the drug (Controls). Adolescents were tested using two intensities of prepulses (70 and 85 dB) combined with a 105 dB startle stimulus, delivered across two testing blocks. RESULTS: There was a significant interaction of group by block for PPI; marijuana users experienced a greater decline in the PPI across the testing session than Controls. The change in PPI of response magnitude for users was predicted by change in urine THC/creatinine after at least 18 h of abstinence, the number of joints used during the previous week before testing, as well as self-reported DSM-IV symptoms of marijuana tolerance, and time spent using marijuana rather than participating in other activities. CONCLUSIONS: These outcomes suggest that adolescents who are frequent marijuana users have problems maintaining prepulse inhibition, possibly due to lower quality of information processing or sustained attention, both of may contribute to continued marijuana use as well as attrition from marijuana treatment.