Biomedical subjects

Sarah Kerrigan

Publications and source records attributed to Sarah Kerrigan.

10 recordsLinked to original sources

PubMed2006

The influence of site of collection on postmortem morphine concentrations in heroin overdose victims.

When assaying for postmortem morphine concentration, significant site sampling variability exists between central and peripheral sampling sites and even within sampling regions of the body. To study the variation, 76 suspected heroin overdoses were identified. Each had femoral artery (FA) and vein (FV), left and right ventricle and pooled heart blood samples obtained at autopsy. Forty-four tested positive for morphine. Morphine concentrations were determined by gas chromatography/mass spectrometry, with sampling site differences reported as log-transformed ratios and compared by signed rank test. The mean FA to FV ratio for total morphine was 1.2 (range 0-4.5). The ratio for left heart to right heart total morphine was 1.1 (range 0.4-3.2). Left ventricular to FV total morphine ratio was 2.0 (range 0.6-6.9). In these opioid overdose deaths, FA and FV morphine concentrations are usually similar, although up to 4.5-fold differences were noted. Centrally obtained morphine concentrations are on average twice as high compared with peripheral morphine concentrations. Left and right ventricular morphine concentrations were usually similar, although up to 3.2-fold differences were noted (left side higher).

Adolescent↗

PubMed2005

Fatal caffeine overdose: two case reports.

Caffeine is a mild central nervous stimulant that occurs naturally in coffee beans, cocoa beans and tea leaves. In large doses, it can be profoundly toxic, resulting in arrhythmia, tachycardia, vomiting, convulsions, coma and death. The average cup of coffee or tea in the United States is reported to contain between 40 and 150 mg caffeine although specialty coffees may contain much higher doses. Over-the-counter supplements that are used to combat fatigue typically contain 100-200 mg caffeine per tablet and doses of 32-200mg are included in a variety of prescription drug mixtures. Fatal caffeine overdoses in adults are relatively rare and require the ingestion of a large quantity of the drug, typically in excess of 5 g. Over a period of approximately 12 months our office reported two cases of fatal caffeine intoxication. In the first case, the femoral blood of a 39-year-old female with a history of intravenous drug use contained 192 mg/L caffeine. In the second case, femoral blood from a 29-year-old male with a history of obesity and diabetes contained 567 mg/L caffeine. In both cases, the cause of death was ruled as caffeine intoxication and the manner of death was accidental.

Adult↗

PubMed2005

Evaluation of a portable evidential breath alcohol analyzer.

The Scientific Laboratory Division (SLD) of the Department of Health acts by mandate as the regulatory agency for the Implied Consent Program for the State of New Mexico. The Laboratory is responsible for all blood and breath alcohol testing activities for law enforcement statewide. The geographical size and the nature of the state, characterized by a highly rural population, demands portable breath alcohol testing equipment. Moreover, future expansion and success of the breath-testing program has focused on instrument portability and data management as critical issues amongst law enforcement agencies and the courts. Thus, the Implied Consent Section of the SLD evaluated the performance of the Intoxilyzer 8000, a portable instrument, against the Intoxilyzer 5000, a stationary instrument, which is currently approved for use. Instrument performance was evaluated at various ethanol concentrations, ranging from 0.04 to 0.55 g/100mL in blood or g/210 L breath. Special attention was placed on instrument performance at the per se and aggravated DWI levels of 0.08 g/100mL and 0.16 g/dL, respectively, due to their legal significance. Precision and accuracy were evaluated using in-house ethanol controls in a wet bath simulator. Coefficients of variation using the Intoxilyzer 8000 ranged from 0.30 to 1.3% (n=102), while CVs for the Intoxilyzer 5000 were 0.7-2.1% (n=102). Calibration stability was assessed in addition to the distribution of data at concentrations between 0.04 and 0.55 g/210 L. Accuracy was 100-102% for the Intoxilyzer 5000 and 99-101% using the Intoxilyzer 8000. Linear regression analysis of more than 700 comparative measurements revealed an R(2) of 1.000 (y=1.005x-0.001), where the Intoxilyzer 5000 and the Intoxilyzer 8000 were plotted on the x- and y-axis respectively. Instrument response to mouth alcohol and volatile interferences was also investigated. Potential interferences were evaluated alone or in combination with ethanol using a wet bath simulator at 34.0 degrees C. The effects of extreme temperature and altitude were also examined using wet bath simulators and dry gas calibrant. Accuracy and precision were evaluated at high and low temperatures. High altitude performance was evaluated at 3534 m above sea level at a local ski resort. In addition to the scientific study, field evaluations were also conducted by law enforcement personnel. Based upon the results of the study, the Intoxilyzer 8000 was approved as an evidential breath alcohol analyzer in the State of New Mexico.

Altitude↗

PubMed2004

Strychnine overdose following ingestion of gopher bait.

A 52-year-old male was discovered supine on his bed in a state of early decomposition. Commercial strychnine-treated gopher pellets were found in the home, and suicide notes were present at the scene. Biological fluids and tissues were tested for basic, acidic, and neutral drugs using gas chromatography-mass spectrometry. Concentrations of strychnine in heart and femoral blood were 0.96 and 0.31 mg/L, respectively. Vitreous fluid, bile, urine, liver, and brain specimens contained 0.36 mg/L, 1.17 mg/L, 2.92 mg/L, 4.59 mg/kg, and 0.86 mg/kg strychnine, respectively. No other drugs were detected in any of the samples. The cause of death was attributed to rodenticide poisoning, and the manner of death was suicide.

Animals↗

PubMed2004

Postmortem morphine concentrations following use of a continuous infusion pump.

We report a case involving unusually high postmortem morphine concentrations in a 44-year-old male with end-stage pancreatic cancer. He was receiving morphine for pain control via a single subclavian intravenous catheter. Allegations of foul play were made by family members at the time of death, so a full autopsy was performed. Comprehensive toxicology on autopsy samples indicated that morphine was the only drug present. Quantitative analysis of free and total morphine revealed extraordinarily high concentrations of the drug. Free morphine concentrations in heart blood, vitreous fluid, brain, liver, stomach contents, and urine were 96 mg/L, 52 mg/L, 26 mg/kg, 88 mg/kg, 82 mg/L, and 976 mg/L, respectively. Total morphine concentrations in heart blood, vitreous fluid, brain, liver, and stomach contents were 421 mg/L, 238 mg/L, 65 mg/kg, 256 mg/kg, and 325 mg/L, respectively. Records indicate that the infusion pump may have continued to deliver the drug for 15-45 min following death. Despite compelling toxicological data, the cause of death was determined to be complication of adenocarcinoma of the pancreas, and the manner was natural. This report highlights issues surrounding postmortem toxicological interpretation within the context of chronic pain management.

Adult↗

PubMed2004

Fatal bupivacaine intoxication following unusual erotic practices.

A fatal drug overdose is described which involved unusual erotic practices. A 54-year-old male was discovered supine on the floor surrounded by sexual paraphernalia, syringes, and medications including three empty bottles of bupivacaine. Acute and chronic injection sites of the external genitalia with contusions, scarring, focal necrosis, and calcification were present at autopsy. Toxicology revealed femoral blood, heart blood, and vitreous bupivacaine concentrations of 3.8, 2.8 and 1.3 mg/L, respectively. The urine bupivacaine concentration was 11.4 mg/L. The cause of death was attributed to bupivacaine intoxication and the manner of death was accidental.

Anesthetics, Local↗

PubMedDate not supplied

In vitro production of gamma-hydroxybutyrate in antemortem urine samples.

The in vitro production of gamma-hydroxybutyrate (GHB) in antemortem urine samples was demonstrated over an eight-month period. Positive chemical ionization-gas chromatography-mass spectrometry (PCI-GC-MS) was used to detect trace amounts of GHB produced in vitro under certain storage conditions. Freshly prepared drug-free human urine was stored at 21, 4, and -20 degrees C in the presence of preservative. Although artifactual production of GHB occurred more rapidly at elevated temperatures, the presence of an antimicrobial agent (sodium azide) in the drug-free urine control did not impede GHB production. The preliminary data suggest that although in vitro production was demonstrated, the elevations in concentration were nominal and less than 5 mg/L for all conditions tested over the 244-day period. These preliminary data suggest that urine samples should be preserved and stored at -20 degrees C to minimize artifactual GHB production. Most importantly, conditions of storage and preservative should also be taken into consideration when interpreting GHB results that are close to the administrative cutoff. In order to establish the distribution of GHB concentrations in routine forensic case samples, a series of 100 antemortem urine samples, in which GHB was not suspected, was analyzed. Samples were preserved with sodium fluoride (1%) and had been stored for up to one year at room temperature. Although concentrations as high as 7 mg/L were measured in some samples, the mean and median concentrations were 1.8 mg/L and 1.6 mg/L, respectively. Even following storage at room temperature for an extended period, more than 95% of the urine samples contained less than 5 mg/L GHB and 100% contained less than 10 mg/L. An administrative cutoff of 10 mg/L in antemortem urine was used for routine antemortem casework.

Artifacts↗

PubMedDate not supplied

Comparative alcohol concentrations in blood and vitreous fluid with illustrative case studies.

The Toxicology Bureau of the New Mexico Department of Health performs drug and alcohol testing on approximately 2800 medical examiner cases each year across the entire state. Although blood is usually the preferred specimen for alcohol analysis, the importance of multiple specimen analysis in alcohol-related death investigation is well understood. Quantitative alcohol determination in a variety of postmortem specimens may provide important interpretive information. In a total of 322 consecutive cases, blood and vitreous alcohol concentrations were compared. No alcohol was detected in either specimen in only 27 of the cases. In the remaining 295 investigations, alcohol was detected in the vitreous fluid, blood, or both. Analysis of the data and presentation of case studies reinforce the need for multiple specimen analysis in alcohol-related death investigation. Postmortem blood and vitreous alcohol concentrations were compared in a series of 295 alcohol-positive cases. The vitreous alcohol concentration (VAC) exceeded the blood alcohol concentration (BAC) in 209 cases (71%). Blood alcohol concentrations exceeded vitreous concentrations in 81 cases (27%), and the concentrations were equivalent in 5 cases (2%). For the purpose of this study, samples that were negative in both specimens were excluded. In casework where the VAC > BAC, linear regression analysis indicated an R2 value of 0.958 (n = 209) and a VAC approximately 16% higher than the BAC. The VAC/BAC ratio was more variable at lower BACs (< 0.1 g/100 mL). The source of blood for this data set was predominantly femoral (n = 203), followed by heart (n = 5) and pleural cavity (n = 1). Although VAC/BAC ratios were more consistent at concentrations of 0.1 g/100 mL and above, the overall ratio ranged from 1.01 to 2.20. Of the 81 cases where BAC > VAC, a total of 24 cases indicated no vitreous alcohol. The range of blood alcohol concentrations among these cases was widely variable (0.01 to 0.30 g/100 mL). Unlike the VAC/BAC data set which consisted of 97% femoral blood, the source of blood in the BAC > VAC data set was slightly more variable. Of the 81 cases where BAC > VAC the blood source consisted of femoral (n = 68), heart (n = 8), pleural cavity (n = 2), carotid (n = 1), jugular (n = 1), and chest blood (n = 1). All analyses were conducted using dual-column gas chromatography with flame-ionization detection (GC-FID) with a reporting limit of 0.01 g/100 mL ethanol in postmortem samples. A series of case studies are used to demonstrate postmortem interpretive issues and the benefits associated with multiple specimen analysis. Cases include postmortem production of ethanol, rapid or unexpected death during the absorptive phase, and site-dependent differences following traumatic injury. Actual case studies involving other volatile organic compounds are also presented including isopropanol and acetone from endogenous and exogenous sources. Many of these cases studies highlight the difficulty associated with postmortem alcohol interpretation in the absence of multiple specimens or adequate case history.

Accidents↗

PubMedDate not supplied

Distribution of GHB in tissues and fluids following a fatal overdose.

Gamma-hydroxybutyrate (GHB) is encountered in biological specimens as an endogenous neuromodulator, recreational drug, or therapeutic agent. Clinically, the drug is useful for the treatment of cataplexy. Illicit doses are typically 2-4 g, and the onset of action is rapid, occurring 15-30 min following oral ingestion. Dose-dependent effects include drowsiness, euphoria, dizziness, vomiting, respiratory depression, coma, and death. GHB was isolated from biological samples using a simple liquid-liquid extraction. The trimethylsilyl derivative (GHB-di-TMS) was analyzed using gas chromatography-mass spectrometry with positive chemical ionization. Deuterated internal standard and selective ion monitoring were used throughout. We report a GHB fatality involving a 35-year-old male who was partying with friends. Subjects at the party ingested unknown quantities of wine and GHB. A female companion at the party reported seeing the male alive before she herself passed out. She awoke to find the decedent cold and stiff. Postmortem specimens were submitted for comprehensive toxicology testing. No alcohol or common drugs of abuse were detected. A targeted analysis revealed GHB in urine, brain, vitreous fluid, femoral blood, heart blood, and liver at concentrations of 1665 mg/L, 102 mg/kg, 48 mg/L, 461 mg/L, 276 mg/L, and 52 mg/kg, respectively. Concentrations of the drug in urine and vitreous fluid are important in death investigations because of significant postmortem production of GHB in blood specimens. The cause of death was attributed to GHB intoxication, and the manner of death was accidental.

Adult↗

PubMedDate not supplied

The influence of collection site and methods on postmortem morphine concentrations in a porcine model.

This study was to determine the relationship of antemortem to postmortem morphine concentrations in heart and femoral blood in a porcine model following acute intravenous opiate overdose. The study involved 20 swine; each was sacrificed 10 min after injection of 2 mg/kg body weight of morphine. Drug concentrations were assayed from vitreous humor and blood isolated from the femoral vein and artery and left and right ventricles at various times postmortem. Comparisons were made between antemortem and postmortem values to determine agreement and reliability. Both free and total postmortem values varied significantly among animals, sampling sites, and over time. Free postmortem values were generally higher in comparison with antemortem values, whereas postmortem total morphine values were similar to or slightly lower than antemortem values. The effect of time on postmortem values was small. These results demonstrate a significant amount of variability in free and total morphine measurements both over time and within and between sites. Furthermore, a comparison of antemortem to postmortem values demonstrates a lack of consistency relative to the dose of morphine administered. Concentrations of morphine in the femoral vein were typically the lowest observed. This observation is not surprising given the transformation that occurs prior to the drug reaching the femoral vein. Values associated with diffuse tissues, relative to femoral veins, demonstrate more stochastic variation.

Analgesics, Opioid↗