The effect of blood in the oral cavity on breath alcohol analysis

The theory that blood (containing alcohol) present in the oral cavity may falsely increase breath analysis recently led to a successful appeal against a drink driving conviction. Subjects who had previously consumed vodka (37.2% alc/vol), at 30 ml/10 kg and reached a BAC (blood alcohol concentration) of between 0.05 and 0.10% were then given four oral solutions consisting of a control (distilled water), and 0.05, 0.10 and 0.15% aqueous alcohol (ethanol) solutions, administered in coded form. A four-way cross-over, blind, randomized assay was conducted with the solutions, with breath analyses conducted in the presence or absence of solution in the mouth. The first trial group (n = 18) received 2 ml of solution, and we found that the simulated 0.15, 0.10 and 0.05% alcohol solutions in the mouth produced BAC reading increases of 0.0088 +/- 0.0014, 0.0062 +/- 0.0008 and 0.0055 +/- 0.0010% respectively (p < 0.001). The second trial group (n = 20) received 1 ml of solution and produced BAC reading increases of 0.0047 +/- 0.0011 (p < 0.001), 0.0023 +/- 0.0008 (p < 0.01) and 0.0020 +/- 0.0006% (p < 0.05) respectively. In conclusion, these studies indicate that small volumes of blood (containing alcohol) in the mouth would not have a practical effect on breath analysis readings.     

胸腹部CT扫描呼吸方法的探讨--过度换气呼气末屏气与平静呼吸吸气末屏气的比较

目的通过平静呼吸吸气末屏气(组)A与过度换气呼气末屏气(组)B的比较,找出既能增加屏气时间,又能减少层面差异的方法。方法选胸腹部CT检查的病人(志愿者),进行呼吸训练,用秒表测量A组与B组的屏气时间;两组病例均做常规螺旋CT扫描,选取一定层面做一次扫描,记录其与螺旋CT扫描图像中相同层面的床位差为层面差。结果两组屏气时间男性有显著差异(P<0.001,t=6.317),女性亦有显著差异(P<0.001,t=12.98)。层面差异测量,两组比较胸部有显著差异(P<0.001,t=5.662),上中腹部有显著差异(P<0.001,t=5.548)A组胸部和上中腹部之间无显著差异(P>0.2,t=1.073)B组。,胸部和上中腹部之间无显著差(P>0.5,t=0.4979)。结论B组屏气时间比A组明显增加,两组屏气的时间男性大于女性,两组屏气时间增加率男性小于女性。同层扫描可重复性的呼吸控制方法,组优于A组。B     

The effect of salbutamol on breath alcohol testing in asthmatics.

Subjects suffering from asthma can occasionally experience difficulty in providing adequate breath samples for evidential breath alcohol testing devices and may therefore resort to the use of bronchodilators such as salbutamol to improve their respiration. Experiments showed that although salbutamol caused bronchodilation it did not affect breath alcohol levels of asthmatics who have been drinking. The blood:breath alcohol ratios obtained from asthmatics were within the normally recorded range before and after use of salbutamol. We conclude that the use of salbutamol by asthmatics does not affect the reliability of measurements made by evidential breath alcohol testing devices.     

Concentration dependency of the BAC/BrAC (blood alcohol concentration/breath alcohol concentration) conversion factor during the linear elimination phase

According to the theoretical pharmacokinetical considerations put forward by Wehner et al. the BAC(ven)/BrAC conversion factor Q is not a constant value and varies depending on the pharmacokinetic phase deduced from the alcohol concentration curve. Based on these considerations we propose that Q must be inversely proportional to the BrAC during the postabsorptive linear elimination phase, expressed as the hyperbola Q=1/kappa+(CT)/BrAC. The constants kappa or 1/kappa and (CT)--where (CT) consists of different parameters which remain constant during the linear elimination phase--can be experimentally determined from the linear relationship BrAC = kappaBAC(ven)-kappa(CT). To test this hypothesis 12 human volunteers received parenteral doses of ethanol. During the elimination phase, BAC and BrAC of each volunteer were measured between 18 and 34 times in a BrAC range between 0.65 mg/l and 0.12 mg/l. The conversion factor Q was either expressed in the form of the hyperbola Q=1/kappa+(CT)/BrAC or directly calculated from the ratio BAC(ven)/BrAC and the results obtained using both methods were found to be very similar. The values of 1/kappa of the hyperbolic functions varied between 1.808 and 2.165 and those of (CT) between 0.004 and 0.127. For a BrAC of 0.25 mg/l, an average value of 2.308+/-0.080 could be calculated for the conversion factor Q(0.25). On average, the value of Q(0.40) amounted to 2.207+/-0.048 and that of Q(0.55) to 2.160+/-0.056.     

重庆地区驾驶员血液中乙醇浓度与驾驶能力的关系

目的　探讨重庆地区驾驶员血液中乙醇浓度 (BAC)和驾驶能力的关系 ,为交通安全立法提供科学依据。　方法　随机选择重庆地区 59名驾驶员志愿者 ,建立饮酒后驾车模型、科学的BAC测定以及驾驶能力评价体系 ,对不同BAC下驾驶能力进行测评。　结果　受试者出现驾驶能力损害时的BAC均数为 685.9mg/L ,最小值 190 .0mg/L ,最大值 152 0 .0mg/L ,总体均数 95%可信区间为 60 2 .4～ 70 9.5mg/L。汉族和土家族间、汉族男性和女性间、2 3～ 3 5岁和 3 6～ 56岁年龄组间差异无显著性意义 (P >0 .0 5) ,而既往饮酒量不同的三个组别间差异有显著性意义 (P <0 .0 5)。随着BAC增高 ,驾驶能力受损人数增加。在 2 0 0 .0mg/L有 3 % (2 / 59)的受试者驾驶能力降低 ,80 0 .0mg/L则达到 68% (40 / 59)。　结论　随着BAC增高 ,重庆地区驾驶员驾驶能力受损人数比例增加 ,出现驾驶能力明显损害时BAC为 60 2 .4～ 70 9.5mg/L ,既往酒量较大人群中该值较高     

The relationship between blood and urine alcohol concentrations at autopsy

The relationship between the blood alcohol concentration and the urine alcohol concentration was studied in 109 routine coroner's autopsies. Although the average ratio for urine alcohol concentration to blood alcohol concentration lay close to the ratio of 4:3 quoted in the literature, the actual ratios determined were widely scattered around this value. Thus the use of this simple ratio to estimate the blood alcohol concentration from the urine alcohol concentration at post-mortem was unreliable. An equation determined by employing linear regression analysis was similarly unhelpful in enabling one to derive a precise value for the blood alcohol concentration from a given urine alcohol concentration. It was concluded that the main value in determining the urine alcohol concentration at autopsy was to exclude the possibility of the alcohol present in the blood sample having been generated during the post-mortem interval.     

Pilots' knowledge of blood alcohol levels and the 0.04% blood alcohol concentration rule

A national sample of licensed pilots was surveyed regarding their knowledge of the Federal Aviation Administration's (FAA) 0.04% blood alcohol concentration (BAC) limit, the relationship between the number of drinks and BAC, and the manner in which BAC decays with time. A majority of the 1039 respondents were unaware of the 1985 0.04% BAC rule change. In addition, many lacked an understanding of the relationship between the amount of alcohol consumed and the resulting BAC, and of the rate at which BAC decays. The number of drinks necessary to raise BAC to specific levels was frequently overestimated, and the amount of time necessary for BAC to decay was frequently underestimated. These errors were more pronounced for moderate and heavy drinkers than for abstainers and infrequent drinkers. These results suggest that pilots could have difficulty if they attempt to use the 0.04% BAC value as a guide to safety in their flying activities.     

On determining the relationship between blood alcohol concentration and smooth pursuit eye movements

Residual impairment after alcohol consumption implies that the relationship between blood alcohol concentration (BAC) and deficits in performance of some task is not the same when becoming intoxicated as it is when returning to sobriety. A pilot study was performed to determine the feasibility of and the appropriate methodology for studies on residual impairment of smooth pursuit performance. Four subjects consumed alcohol for 2 h. Measurements of BAC and smooth pursuit eye movements were made every 30 min during drinking and for 4 h after drinking. Pursuits were elicited by having subjects track a sinusoidal target (0.40 Hz and 0.60 Hz) for 10 s. Impairment of smooth pursuit was quantified with frequency analysis scores. Frequency analysis scores declined as BAC increased. As BAC decreased, frequency analysis scores tended to increase toward pre-drink levels. The relationship between BAC and frequency analysis score was not significantly different on the ascending and descending limbs of the blood alcohol curve. However, the idea that residual impairment does not occur could not be conclusively demonstrated for several reasons. First, as BAC returned to pre-drink levels, frequency analysis scores were inconsistent for each subject perhaps because of boredom and fatigue. Second, the relationship between BAC and frequency analysis score varied between subjects. Finally, because the recording periods were short, the effect of alcohol on sustained attention could not be assessed. In this paper, potential artifacts in studies of residual impairment of pursuits are discussed and potential solutions to the methodological problems encountered in the pilot study are provided.     

Intra-individual and inter-individual variation in breath alcohol pharmacokinetics: Variation over three visits

Eleven male and 7 female student subjects underwent serial Breath Alcohol Concentration (BrAC) measurements after being given alcohol as 13% white wine (5.7 ml/kg for males and 4.7 ml/kg for females) in a fasting state on three separate occasions. BrAC versus time curves were constructed for each subject and the values of peak BrAC (C_max), theoretical BrAC extrapolated at zero time (Co), time taken to reach peak (T_max) and rate of elimination (ß) from breath were recorded directly from the curves. Average Intra-individual variation for each individual between the 3 visits (for males and females, respectively) was 5.6% and 8% for Co, 12% and 13% for C_max, 42% and 37% for T_max and 11% and 13% for ß. Inter-individual variation (for males and females) was 7.5% and 13% for Co, 16% and 15% for C_max, 43% and 46% for T_max and 21% and 15% for ß. Average elimination rates in males (5.3 μg/100 ml breath/h, range 4–7.7) and females (5.6 μg/100 ml breath/h, range 4–7) were not significantly different. Widmark factors calculated by various established mathematical methods were 0.71–0.81 in males and 0.59–0.68 in females, higher than the originally quoted mean experimental levels.     

Intra-individual and inter-individual variation in breath alcohol pharmacokinetics: The effect of short-term variation

Ten male and 8 female students underwent serial breath alcohol concentration (BrAC) measurements on a CAMIC Datamaster on two consecutive occasions, early evening and again the following morning. Subjects were fasted for 6 h before receiving alcohol as white wine (12.5% by volume) at doses of 38–45 g for males and 26–37 g for females, consumed over 10 min. Specific individual doses were calculated individually from height and weight (according to the Forrest Method) to give target C₀ breath alcohol concentrations of 35 μg/100 ml breath in males and 31 μg/100 ml breath in females.BrAC versus time curves were constructed for each subject and the values of peak BrAC (C_max), BrAC extrapolated at zero time (C₀), time taken to reach peak (T_max) and rate of elimination (ß) were recorded directly from the curves. Values of C₀ taken from the BrAC–time curves varied widely, from 21 to 47 μg/100 ml on visit 1 and from 22 to 45 μg/100 ml on visit 2. Widmark Factors calculated from these C₀ values averaged 0.74 (range, 0.59–1.06) in males and 0.73 (range, 0.58–1.05) in females. Elimination rate was higher in the morning than evening in both males (7.4 versus 5.7 μg/100 ml/h) and females (6.9 versus 5.8 μg/100 ml/h). Elimination rates in males and females were not significantly different. Total body water, measured by electronic scales, averaged 58.7% (range, 56.6–63%) in males and 48.3% (range, 40.9–57.6%) in females. Widmark Factors calculated by various established mathematical methods were 0.73–0.77 in males and 0.61–0.64 in females.     

Volatile substances and their potential to interfere with breath alcohol reading instruments

Two cases are presented which highlight the potential for abused volatile substances to interfere with the results of evidential breath testing equipment. Home Office guidance, issued in 1983, advises that breath testing devices should not be used when a driver is suspected of glue-sniffling, but the advice does not appear to be widely known. The implications for both police officers and police surgeons are discussed. New evidential breath testing devices, which are planned to be introduced into the UK in the first half of 1997, are designed to recognize interfering substances such as solvents. The potential problems these new devices may pose are considered.     

体外不同程度生理盐水稀释血液对凝血功能的影响

目的 探讨用生理盐水在体外不同程度地稀释血液对凝血功能的影响.方法 将19名成年健康志愿者的静脉血在体外用生理盐水稀释成体积比20%(生理盐水:血液=2:8),30%(生理盐水:血液=3:7),40%(生理盐水:血液=4:6),50%(生理盐水:血液=5:5),60%(生理盐水:血液=6:4)等5个梯度,并用未经稀释的全血作为对照.用Sonoclot凝血及血小板功能分析仪进行凝血功能检测,测量的数据包括激活的凝血时间(ACT)、凝结速率(CR)、达峰时间(TP)、最大凝血标记值(MCS)、血小板功能(PF)等.结果 与对照组比较,20%稀释后ACT显著缩短(P<0.05),60%稀释后ACT显著延长(P<0.05),其余稀释度差异无统计学意义(P>0.05).20%稀释后CR显著升高(P<0.05),50%、60%稀释后CR显著降低(P<0.05),其余稀释度差异无统计学意义(P>0.05).20%稀释后TP显著缩短(P<0.05),其余各稀释度差异无统计学意义(P>0.05).60%稀释后MCS显著降低(P<0.05),其余各稀释度差异无统计学意义(P>0.05).20%稀释后PF显著升高(P<0.05),其余稀释度差异无统计学意义(P>0.05).结论 血液稀释后凝血功能与血液稀释程度相关,生理盐水占20%加快了血液凝固的进程,30%、40%稀释的凝血功能未受影响,50%稀释的血液凝固能力开始减弱,60%稀释的血液凝固能力受到严重影响.     

The role of blood alcohol dehydrogenase in pathological alcohol involvement

The authors have revealed the distinct parallelism between clinical state of patients with alcoholism, activity of alcohol dehydrogenase (ADG) in their blood plasma and presence of signs of pathologic inclination for alcohol (PIA). The marked PIA signs were accompanied by high ADG activity in blood. It permits to combine the presence of PIA and enzyme high activity into single pathogenetic mechanism and suggest that together with metabolic function ADG performs the receptor one. Also it is possible to assume that use of drugs decreasing ADG activity and restoring ethanol content in organism of patients with alcoholism will contribute to PIA release. Use of such drugs can become one of the safe methods in alcoholism therapy.     

The effect of respiratory aerosol inhalers and nasal sprays on breath alcohol testing devices used in Great Britain

Subjects suffering from respiratory diseases occasionally experience difficulty when attempting to provide breath samples to satisfy the requirements of breath alcohol testing devices. In order to assist ventilation, such subjects may resort to the use of an aerosol inhaler. Twenty aerosol inhalers containing drugs which exhibit an effect on the respiratory system and five nasal sprays used to relieve the symptoms of hay fever, have been tested for interference on the range of breath alcohol measuring devices used by the police in Great Britain. No interference attributable to the contents of any of the aerosol inhalers or nasal sprays tested was observed on any of the instruments in police use.