Lack of effect on blood alcohol level of swabbing venepuncture sites with 70% isopropyl alcohol

Objective: It is standard practice to clean the skin using a non‐alcohol‐containing swab before forensic blood alcohol sampling, because of the belief that the use of an alcohol‐containing swab will contaminate the sample. The present study aimed to determine whether cleaning the skin with 70% isopropyl alcohol swabs, before venepuncture, alters measured blood alcohol level (BAL). Methods: Volunteers aged >18 years had paired venous blood tests, which were drawn within 2 min of each other. One arm was swabbed with a 70% isopropyl alcohol swab and allowed to dry before venepuncture. The other was swabbed with saline, and these concurrent samples were used as controls. BAL was tested using the enzymatic method. Pathologists analysing the samples were blinded to the swabbing technique used. The mean differences and standard deviations of each of the paired samples were analysed using Student's t‐test. Results: Fifty‐six paired venous blood samples were obtained from volunteers. Mean BAL in the isopropyl alcohol‐swabbed group was 3.27 mg/dL with a standard deviation of 1.14 mg/dL. Mean BAL in the saline‐swabbed group was 3.41 mg/dL with a standard deviation of 1.11 mg/dL. The mean difference was 0.14 mg/dL, with a standard error of 0.157. There was no statistically significant difference between the groups. Conclusions: The present study demonstrated that the use of 70% isopropyl alcohol swabs does not significantly affect BAL when used before venepuncture. This has implications that challenge current forensic blood alcohol sample acquisition.     

Effect of using alcoholic and non-alcoholic skin cleansing swabs when sampling blood for alcohol estimation using gas chromatography

A study was carried out using 20 volunteers in whom venepuncture through the skin soaked in either ethyl or isopropyl alcohol was performed. A non-alcoholic cetrimide/chlorhexidine swab was used as a control. All subjects were initially alcohol free. Ethyl alcohol was detected in only one blood sample and the level was found to be only 0.4 mg% (roughly the limit of detection of the assay). A slightly higher level of isopropyl alcohol (3 mg%) was found in one of the blood samples. Alcohol estimation was carried out by head-space gas chromatography using a pair of instruments each fitted with a column exhibiting different retention characteristics. The system was similar to that used by other UK Forensic Science Laboratories where accurate, definitive results are a necessity. It was concluded that under very testing conditions only minute ethanol interference is produced by using alcohol-based skin cleansing swabs. This minimal interference is unlikely to affect clinical sample results, and even in a forensic situation the inadvertent use of alcohol-based swabs is unlikely to lead to a miscarriage of justice.     

Does the clinical use of ethanol-based hand sanitizer elevate blood alcohol levels? A prospective study

BackgroundEthanol-based hand sanitizers (EBHSs) are used in most health care facilities in the United States. Infection control personnel advocate the use of generous quantities of EBHS before and after contact with patients. Although it is assumed that little systemic absorption of ethanol occurs during EBHS use, many alcohols are absorbed to varying degrees via the transdermal route. Ethanol intoxication by employees in the medical workplace is a potentially serious finding, and it is of forensic and medical-legal importance to elucidate the effects of frequent use of EBHS upon serum blood ethanol levels (BELs). To investigate the effect of frequent use of EBHS upon serum blood ethanol concentrations, we prospectively studied 5 volunteers undergoing frequent application of EBHS.MethodsEnrolled subjects applied 5 mL of the product (62% denatured ethyl alcohol manufactured by Kimberley-Clark, Roswell, GA) to both hands and rubbed until dry. This activity was repeated 50 times over 4 hours. Participants had their blood drawn before as well as after completing the study. Each participant was without alcohol exposure during the 12 hours preceding the study.ResultsFive volunteers were enrolled. All had an initial blood ethanol level of less than 5 mg/dL. All 5 participants completed the 4-hour study. There were no noted adverse reactions during the study. Blood ethanol level upon completion of the 50 applications of EBHS was less than 5 mg/dL in all 5 study participants.ConclusionThe results of this study demonstrate that use of ethanol-based hand sanitizers, when frequently used in accordance with labeling, do not raise serum blood ethanol levels.     

Skin disinfection methods: prospective evaluation and postimplementation results

BACKGROUND: Optimal skin disinfection ensures blood safety. In this study, efficacies of the two-step skin disinfection methods used at Canadian Blood Services (CBS) and two one-step methods produced by different manufacturers were compared.
STUDY DESIGN AND METHODS: In each of the three phases of the study, two methods were compared by disinfection of the antecubital fossae of study subjects. The two-step methods were compared in Phase I: Method A (isopropyl alcohol scrub and iodine tincture ampule) and Method B (isopropyl alcohol and chlorhexidine scrub and isopropyl alcohol and chlorhexidine ampule). In Phases II and III, Method B was compared to two different one-step swab sticks containing isopropyl alcohol and chlorhexidine (Methods C and D). Contact plates were applied on each of the subjects before and after disinfection and incubated at 37°C for 24 hours followed by colony counting.
RESULTS: In 99% of the subjects, colonies per plate were reduced from approximately 60 to less than 10 after disinfection using any method. Method B was superior to Method A (p < 0.05) but was not significantly different from Methods C and D. Method D was implemented for skin disinfection at CBS with no significant effects on blood product contamination. Skin reactions increased from approximately 0.02% to approximately 0.62% after implementation, which were subsequently reduced to approximately 0.04%.
CONCLUSION: In this study, isopropyl alcohol and chlorhexidine disinfectants were more efficacious than isopropyl alcohol and iodine. There was no difference in efficacy between one-step and two-step procedures or between methods of application. A one-step chlorhexidine and isopropyl alcohol kit has been successfully implemented at CBS.     

Analyses comparing the antimicrobial activity and safety of current antiseptic agents: a review.

This article reviews the results and conclusions from four pivotal and two comparative clinical trials. The six randomized, controlled, single-blinded, parallel-group clinical trials were conducted to determine which antiseptic is best for use as a patient preoperative skin preparation. The objective of these studies was to compare the immediate, persistent (residual), and cumulative antimicrobial efficacy and safety of 2% chlorhexidine gluconate (CHG) combined with 70% isopropyl alcohol (IPA) (ChloraPrep); another combination CHG and IPA antiseptic (CHG+IPA) and 2% aqueous CHG alone; 4% CHG (Hibiclens) alone; 70% isopropyl alcohol (IPA) alone; and an iodine-containing solution, 10% povidone-iodine (Betadine) alone as preoperative skin topical antiseptics for potential prevention of nosocomial infections.     

Effect of common over-the-counter medications on blood alcohol levels

OBJECTIVE: To assess the clinical and legal significance of the potential pharmacokinetic interaction between common over-the-counter (OTC) medications and alcohol that may result in increased blood alcohol levels (BALs). DATA SOURCES: A MEDLINE search (1966-February 2000) of English-language articles was performed using the terms aspirin, acetaminophen, histamine (H2)-receptor antagonist, ethanol, and blood alcohol level and then supplemented by a bibliographic review of relevant articles. STUDY SELECTION AND DATA EXTRACTION: Two H2-receptor antagonist studies using methodologies representative of other published trials and a meta-analysis of 24 H2-receptor antagonist trials were chosen for detailed review. All identified studies examining aspirin and acetaminophen were addressed. DATA SYNTHESIS: More than 30 studies have examined the potential interaction between OTC drugs and blood alcohol. Because this issue has important medical and legal implications for patients, prescribing physicians, and pharmaceutical manufacturers, a critical analysis of the literature addressing this potential interaction is presented. CONCLUSIONS: Numerous factors arguing against a clinically significant interaction were identified. First, data from the relevant studies cannot be extrapolated to the general population because of the multitude of variables that determine an individual's BAL. Also, a publication bias for small studies (< or = 10 subjects) finding a statistically significant increase in peak BAL was observed. In addition, study results supporting an increase in BAL were often irreproducible when these trials were repeated under similar conditions. Finally, although some studies detected statistically significant increases in peak BAL, these changes were often clinically irrelevant.     

Ethanol and Illicit Drugs Do Not Affect the Diagnostic Utility of Base Deficit and Lactate in Differentiating Minor from Major Injury in Trauma Patients

OBJECTIVES: Base deficit (BD) and lactate are valuable screening tools for injured patients. They reflect the degree of oxygen debt and have been shown to predict outcome. Intake of ethanol and illicit drugs may further derange acid-base status. The authors evaluated the effect of blood alcohol level (BAL) and illicit drugs on admission BD and lactate levels in trauma patients. METHODS: Prospective, observational study of trauma patients in a Level 1 trauma center. Patients with penetrating or blunt trauma were included in the study. Patients were further stratified into major or minor categories. Major was defined by an Injury Severity Score >15, blood transfusions, or a decrease in hematocrit of more than ten points. Injury categories were further divided into several subgroups based on presence or absence of ethanol (BAL > or =0.08 g/dL) or positive urine toxicology screen (Utox). RESULTS: A total of 520 patients (84% male) with a mean (+/-SD) age of 33 (+/-15) years were studied. Compared with the minor injury categories, BD and lactate levels were significantly higher in the major injury categories in all different intoxication subgroups. Testing the diagnostic performance of BD and lactate in detecting major injury, the authors observed significant (p < 0.05) differences between the areas under the receiver operating characteristic curves for these two diagnostic tests compared with baseline in both intoxicated (BAL > or =0.08 g/dL and/or positive Utox) and nonintoxicated (BAL <0.08 g/dL and negative Utox) patients. CONCLUSIONS: The presence of ethanol and/or illicit drugs did not affect the ability of BD or lactate to identify patients with major injuries.     

Effects of Oral Doses of Carbaryl on Man

Abstract

A comatose and hypotensive patient was successfully treated with hemodialysis after ingesting 480 mL of isopropyl alcohol. Removal of isopropyl alcohol and its major metabolite acetone was measured in urine, blood, and dialysate. According to dialysate measurements, approximately 19?g of isopropyl alcohol and 7?g of acetone were removed per hour using a standard 1 m² dialyzer. The average dialysance of isopropyl alcohol and acetone were 137 and 165 mL/min, respectively. Removal of isopropyl alcohol was 52 times and acetone 40 times more efficient through hemodialysis than through urinary excretion. Since coma and hypotension portend a bad prognosis and since urinary excretion is slow relative to hemodialysis removal, hemodialysis may be considered lifesaving in patients comatose from isopropyl alcohol poisoning.

There have been two previous reports of hemodialysis used for treatment of isopropyl alcohol intoxication [1, 2]. Neither of these reports describes the kinetics of isopropyl alcohol removal. This paper reports a third patient treated with hemodialysis who afforded us the opportunity to study blood, urine, and dialysate levels of isopropyl alcohol and its chief metabolite, acetone. By utilizing these results a comparison was made of urine excretion to dialysis removal of these compounds to compare their respective efficacy. In addition, the estimated removal by dialysance calculations was compared to estimated removal by measurement of dialysate volumes and concentrations.     

Laboratory testing in ethanol,methanol, ethylene glycol,and isopropanol toxicities

Toxicity from ethanol, methanol, ethylene glycol, and isopropyl alcohol varies widely, and appropriate use of the available laboratory tests can aid in timely and specific treatment. Available testing includes direct measurements of serum levels of these alcohols; however, these levels often are not available rapidly enough for clinical decision making. This article discusses the indications and methods for both direct and indirect testing for ethanol, methanol, ethylene glycol, and isopropanol toxicity. Also discussed are the costs, availability, and turn-around times for these tests.     

Gastric emptying in the acutely inebriated patient.

Fifty inebriated emergency department (ED) patients underwent evacuation of gastric contents via a nasogastric tube, in order to determine if a significant amount of ingested ethanol can be removed prior to absorption. Such a result could potentially reduce additional intoxicating effect. The gastric contents were assayed for total ethanol concentration, and a potential (postabsorption) additive blood alcohol level (PABAL) was projected and compared to the actual BAL on arrival. The type of beverage ingested and the time since last drink were recorded. BAL ranged from 108 to 637 mg/dL (mean +/- SD, 290 +/- 104.7). Gastric aspirate volume ranged from 50 to 700 mL (190 +/- 134), and contained alcohol in a range of 87 to 2271 mg/dL (475 +/- 479). Based on the distribution volume for alcohol calculated according to the patient's weight, this corresponded to a PABAL of 3 to 167 mg/dL (mean, 24.3 +/- 29.3). There was no significant correlation between the volume or concentration of gastric aspirate and the patient's stated drinking history. The authors conclude that a significant amount of ingested alcohol may occasionally be removed from absorption by the routine evacuation of gastric contents in intoxicated patients. These patients cannot be identified upon presentation, however, and these data cannot support routine use of gastric emptying in the detoxification of inebriated patients.     

Evaluation of donor skin disinfection methods

BACKGROUND : Because most bacteria isolated from contaminated platelet concentrates are thought to originate from the donor's skin, the efficacy of four methods of skin disinfection was compared. STUDY DESIGN AND METHODS : Contact plates were used for antecubital skin cultures after they were demonstrated to be easier to use and at least as sensitive as a swab system. One antecubital fossa of each subject was disinfected by a standard method, the use of a povidone-iodine swabstick containing 0.75-percent available iodine followed by the use of a povidone-iodine swabstick containing 1-percent available iodine. The other arm was disinfected with either a 70-percent isopropyl alcohol scrub followed by an ampoule of 2-percent iodine tincture (Group 1; n = 126); a green-soap sponge followed by a 70-percent isopropyl alcohol swab, used for donors who are allergic to iodine (Group 2; n = 30); or a 0.5-percent chlorhexidine gluconate and 70-percent isopropyl alcohol sponge followed by an ampoule of 0.5-percent chlorhexidine gluconate and 70-percent isopropyl alcohol (Group 3; n = 40). Contact plate cultures were done before and after disinfection, and colonies counted after a 48-hour 37°C incubation period. RESULTS : Similar numbers of bacteria grew from both antecubital fossae of the same subject before disinfection (p = 0.71). Compared to the standard povidoneiodine method, isopropyl alcohol and tincture of iodine resulted in significantly less bacterial growth (p<0.001), the green soap and isopropyl alcohol method resulted in significantly more bacterial growth (p<0.001), and the chlorhexidine gluconate and isopropyl alcohol method resulted in similar amounts of bacterial growth (p>0.3). CONCLUSION : Isopropyl alcohol scrub followed by iodine tincture is more efficacious than povidone-iodine as measured by contact plate cultures. For donors who are allergic to iodine, chlorhexidine gluconate and isopropyl alcohol is more efficacious than green soap and isopropyl alcohol.     

Serum determinations in toxic isopropanol ingestion.

A toxic dose of isopropyl alcohol was ingested by six male mongrel dogs to evaluate the relationship between acetone production and isopropyl degradation. Maximal serum isopropyl levels were achieved approximately 2 to 3 hours after ingestion of 60 mL of 70% isopropyl alcohol. Acetonemia occurred rapidly in the serum (within 15 minutes of ingestion) and continued to rise after isopropanol levels plateaued. The levels of acetone and isopropanol correlated positively throughout the study model with an r of .54 (P less than .001). It is concluded that there is a positive relationship between acetone production and isopropyl metabolism in the setting of a toxic ingestion of isopropanol. Acetone's persistence as a serum marker may be beneficial in identifying isopropyl hours after a suspected ingestion.     

Effects of skin disinfection method, deviation bag, and bacterial screening on clinical safety of platelet transfusions in the Netherlands

BACKGROUND: Bacterial contamination of blood products is a great hazard for development of fatal transfusion reactions. Bacterial screening of platelet concentrates (PC) by aerobic and anaerobic culturing (BacT/ALERT, bioMérieux) was introduced in the Netherlands in October 2001. STUDY DESIGN AND METHODS: In November 2002, a nationwide, uniform skin cleansing method was introduced with a double-swab disinfection with 70 percent isopropyl alcohol. One location routinely used an integrated diversion bag to collect the first 20 to 30 mL. RESULTS: Over the calendar years 2002 and 2003, in total 113,093 PCs derived from pooled buffy coats were screened. After introduction of the new disinfection method, 0.85 percent were initially positive. This was a small reduction compared to the previous disinfection methods under which 0.95 percent were initially positive. The location with use of the diversion bag showed a significantly lower frequency of bacterial contamination, with 0.50 percent before and 0.37 percent after introduction of 70 percent isopropyl alcohol. In addition 8000 apheresis PCs were also screened, showing 24 initially positive samples (0.30%). CONCLUSION: The use of the diversion bag and, to a lesser extent, the use of double swabs with 70 percent isopropyl alcohol, led to a reduction of contamination. As expected, predominant contamination with resident skin bacteria was reduced. The combination of diversion bag and new disinfection led to a frequency of initial positive results for pooled five-donor PCs, which is similar to that of single-donor apheresis PCs. Furthermore, the bacterial detection system and associated product recall procedures have been shown to be effective in preventing transfusion of contaminated PCs and/or related red cells, especially for rapidly growing bacteria.     

Coordinated FA-MS and SIFT-MS analyses of breath following ingestion of D2O and ethanol: total body water, dispersal kinetics and ethanol metabolism

A coordinated study of the dispersal of water between the various body compartments (stomach and gut, blood stream and tissue) and the similar dispersal kinetics of ethanol and its metabolism has been carried out involving two healthy volunteers using flowing afterglow mass spectrometry, FA-MS, and selected ion flow tube mass spectrometry, SIFT-MS. Thus, using these techniques, the variations of HDO and ethanol in breath, measured in successive single exhalations, were followed in real time after the ingestion of measured quantities of D2O and ethanol in proportion to the body weights of the subjects at the dose rates D2O approximately 0.283 g kg-1, ethanol approximately 0.067 g kg-1. During the FA-MS experimental periods (about 2 h), the dispersion of HDO into the body water and finally its equilibration in the total body water is observed from which total body water for each subject was determined. In the SIFT-MS measurements, the dispersion of ethanol into the body water and its loss via metabolism was observed until the physiological (pre-dose) breath level of ethanol for each individual was restored. A simple linear transformation is used to derive the time variations of the blood levels of HDO and ethanol. This has allowed a comparison of the fractions of the ingested ethanol that are metabolized during first-pass metabolism for the two subjects. Thus, in one subject 30% and in the other subject 40% of the ingested alcohol is metabolized in the first 20 min following ingestion. The good time resolution allowed by non-invasive breath analysis ensures that the rates of processes such as ethanol metabolism can be accurately measured. Simultaneous measurements of breath acetaldehyde (largely formed via the ethanol metabolism) and acetone were also performed during the SIFT-MS single breath exhalations.     

脑外伤患者血液酒精水平与Glasgow评分的关系

目的研究脑外伤患者血液酒精水平对Glasgow评分(GCS)的影响。方法 245例脑外伤患者根据血液酒精水平分为4组,分析各组GCS的差异及血液酒精水平与GCS的相关性。结果各组GCS差异无统计学意义,血液酒精水平与GCS无明显相关性。结论 GCS仍然可以作为饮酒的脑外伤患者昏迷程度的有效评价指标。     

Effect of exposure to heat and intake of ethanol on the skin circulation and temperature in ischaemic limbs

Summary. The question of whether alcohol intake increases skin circulation is controversial. The study described here was undertaken to examine the effect on skin circulation and skin temperature in ischaemic limbs of exposure to external heat, and of alcohol intake together with such exposure. Fourteen patients with occlusive arterial disease, mean age of 65 years (range 47–80), underwent measurements of blood flow by laser Doppler flowmetry (LDF) and of skin temperature 1–2 days before and 8–10 days after vascular reconstruction. LDF and skin temperature were measured in the plantar region of the mid-forefoot with the subject supine. After 30 min of exposure to external heat, the measurements were repeated. Each subject then drank 15 ml of 50% alcohol and after a further 30 min of heat exposure the same measurements were performed again. Similarly, fourteen healthy subjects, mean age 33 years (range 21–43), were studied. In the patients there was no increase in skin blood flow or skin temperature after heat exposure alone or after combined heat exposure and alcohol intake, either before or after vascular reconstruction. In the healthy subjects LDF showed a 126% increase (P<0–01) in skin blood flow after 30 min of exposure to external heat and a further increase by 81% after alcohol intake and an additional 30 min of heat exposure (P<0–01). The corresponding increases in skin temperature were 3–0°C (P<0–05) and 2–9°C (P<0–05). Thus, external heat and alcohol intake increased plantar skin blood flow and skin temperature in healthy subjects but not in patients with ischaemic limbs. The reason for this difference is unclear, but it is possible that the skin vessels in the patients were fully dilated even before heat exposure or alcohol intake.     

Alcohol and conscious level

Many patients presenting to the Emergency Medical Services have recently consumed alcohol. This may profoundly affect their behaviour, conscious level and response to illness and treatment. The blood alcohol level (BAL) is of little use in the evaluation of these responses. Abnormal conscious level should never be ascribed to alcohol intoxication alone. It is only a diagnosis of exclusion. The most commonly associated conditions are head injury, cerebro-vascular incidents, hypoglycaemia and other drug intoxications.     

Clinical Sobriety Assessment by Emergency Physicians in Blunt Trauma Patients with Acute Alcohol Exposure

Background: Alcohol use increases injury risk and severity. However, few studies have evaluated the ability of emergency physicians (EPs) to accurately determine sobriety. Objectives: To determine the predictive value of clinical sobriety assessment by EPs in blunt trauma patients with acute alcohol use. Materials and Methods: Blunt trauma patients, aged 18–65 years with suspected acute alcohol use, were prospectively enrolled in the study. EPs assessed study subjects before sample collection for blood alcohol level (BAL) and urine drug screen measurement. Alcohol exposure was considered significant if BAL was ≥ 80 mg/dL. Sobriety (non-significant alcohol exposure) was defined as a BAL < 80 mg/dL. EP sobriety assessment was compared to measured BAL and predictive values were calculated. Agreement on significance of alcohol exposure occurred if EP-estimated BAL > 80 mg/dL agreed with measured BAL > 80 mg/dL, or estimated BAL < 80 mg/dL agreed with measured BAL < 80 mg/dL. Chi-squared analysis was used to compare the proportion of correct physician assessments among patients with sobriety and those with significant alcohol exposure. Results: Of 158 enrolled subjects, 153 completed clinical assessment. EP assessment had a predictive value of 83% (95% confidence interval [CI] 77–90%) for significant alcohol exposure and 69% (95% CI 60–78%) for sobriety. Agreement on the significance of alcohol exposure was 82% (125/153; 95% CI 76–88%). EPs identified 32% (11/34; 95% CI 17–48%) of sober patients, but identified 96% (114/119; 95% CI 92–99%) of patients with significant alcohol exposure. EP assessment was significantly less accurate in identifying sober patients (p < 0.01). Conclusions: Emergency physicians identified significant recent alcohol exposure in blunt trauma patients 96% of the time. However, clinical assessment by EPs in blunt trauma patients with recent alcohol use had only moderate predictive value for significant alcohol exposure. Sober patients were frequently misidentified as having significant alcohol exposure.     

Clean versus sterile technique for common joint injections: a review from the physiatry perspective

Preparation of the skin prior to joint injection varies widely among disciplines and across regional borders. This is likely due to the paucity of literature on the most effective and efficient methods of preparation. There is no standard definition of clean technique prior to joint injection. Review of the available literature suggests that alcohol is effective preparation for the skin prior to most procedures. Surveys of current clinical practice demonstrate that the use of gloves may be favored, but no conclusions can be drawn in regards to whether sterile gloves are required. Clean technique should be defined as use of non-sterile gloves and agents such as alcohol or soap prior to injection. Significant cost savings may be achieved with the consistent use of clean technique for preparation of the skin prior to joint injection. Further study should address the incidence of iatrogenic bacterial arthritis following clean technique versus sterile technique for joint injection.     

Mechanics of the carotid artery wall and baroreflex sensitivity after acute ethanol administration in young healthy volunteers

The effects of ethanol administered orally (300 mg/kg in 250 ml of water) or intravenously (7.5 mg.min(-1).kg(-1) in 250 ml of saline over 40 min) on common carotid haemodynamics, wall mechanics and baroreflex sensitivity were compared with the effects of the intravenous infusion of 250 ml of saline. Ethanol or saline was administered to 10 healthy volunteers after 30 min of supine rest, and measurements were obtained 40 min (median; range 34-46 min) after administration. After ethanol administration, the plasma alcohol level rose from 0 to 0.3+/-0.07 g/l. Mean arterial blood pressure had risen slightly at 20 min, but was normalized by 40 min, the time at which the haemodynamic study was performed. Heart rate decreased after infusion of either saline or alcohol, but was unchanged after oral ethanol administration. Both oral and intravenous ethanol administration were associated with significant decreases in baroreflex sensitivity, carotid shear stress and blood velocity, compared with resting values, while the mean carotid artery diameter was increased, and blood viscosity and mean blood flow were unchanged. No changes were observed in these parameters after saline administration. Ethanol, administered either intravenously or orally, increased the stiffness of the carotid artery and decreased the pulsatility (systo-diastolic changes) of its diameter. A direct, statistically significant correlation was found between the decrease in shear stress and the decrease in baroreflex heart rate control sensitivity after both modes of alcohol administration, while no such correlation was found between the increase in the Peterson elastic modulus and the decrease in carotid diameter pulsatility on the one hand or the decrease in baroreflex sensitivity on the other. In conclusion, reduced shear stress associated with vasodilatation of the carotid artery wall may contribute to the decrease in baroreflex sensitivity observed after acute ethanol administration.