Tài liệu Drugs and Poisons in Humans - A Handbook of Practical Analysis (Part 8) pdf

Since then, the importance of toxin analysis clinical analytical toxicology on the spots of clinical treatments Wel-fare of Japan decided to distribute an X-ray fl uorescence spectromet

© Springer-Verlag Berlin Heidelberg 2005

I.8 Problems in toxin analysis

in emergency medicine

By Makoto Nihira

Introduction

medi-cine; it requires both rapidness and accuracy In the Japan-shaking poisoning incidents taking place in 1998, such as curry (arsenous acid) poisoning in Wakayama, sodium azide poisoning

in Niigata and cyanide poisoning in Nagano, the importance of a rapid and accurate analysis system for poisons was well recognized by Japanese people and goverment Since then, the importance of toxin analysis ( clinical analytical toxicology) on the spots of clinical treatments

Wel-fare of Japan decided to distribute an X-ray fl uorescence spectrometer to be used for metal analysis together with an HPLC instrument with a photodiode array detector to be used for drug analysis to the 65 critical care medical centers; the above two instruments plus some mass spectrometric instruments for the fi nal identifi cation and quantitation to the 8 advanced criti-cal care medicriti-cal centers Such analyticriti-cal instruments were introduced also to our Advanced Critical Care Medical Center of Nippon Medical School Upon introduction of the state-of-the-art analytical instruments, all staff s of both Department of Legal Medicine and Advanced Critical Care Medical Center discussed together on the selection of each type of instruments, which had been proposed by various manufacturers, for strengthening the toxin analysis sys-tem in emergency medicine at our College Hospital

At Nippon Medical School, the Department of Legal Medicine and the Advanced Critical Care Medical Center have been cooperating for practical analysis and studies on new analytical methodologies of drugs and poisons in specimens sampled from poisoned patients for more

than 20 years since 1980 [1–8] Screening tests are being made at bedside, viz inside the

Ad-vanced Critical Care Medical Center and complicated analysis for identifi cation and

has been also improved to become responsible for the 15 toxic compounds, which were

poi-sonings taking place in the midst of the metropolitan area, where our College is located, are largely due to drugs; they are so-called “urban-type poisonings” [1, 6, 10] caused by illicit drugs

drugs In this chapter, the author presents some of our analytical system and discusses on prob-lems arising during maintaining the system

Analytical system at Nippon Medical School

Screening tests at the emergency rooms

Alcohol: a simple kit for alcohol measurements (alcohol dehydrogenase method) Cyanide: capillary electrophoresis (CE)

Carbon monoxide (CO): oxymeter

2 Drugs

Psychopharmaceuticals and illicit drugs: Triage (immunoassay)

3 Metals

Arsenic, thallium, mercury and others: X-ray fl uorescence spectrometer

4 Pesticides

Bipyridinium pesticides (paraquat and diquat): color tests

Confirmation and quantitation at the laboratories of the Department

of Legal Medicine

Alcohol: GC [headspace method, fl ame ionization detector (FID)]

Toluene: GC (headspace method, FID)

Cyanide: GC (headspace method, nitrogen- phosphorus detector)

2 Drugs

a Amphetamines (methamphetamine, amphetamine and others): GC/MS

b Opiates (morphine, heroin and others): GC/MS

c Cannabinoids (tetrahydrocannabinol and others): GC/MS

a Barbituric acids: GC/MS

c Tricyclic antidepressants: GC/MS

f Sildenafi l citrate (Viagra): LC/MS

4 Pesticides

Bipyridinium pesticides (paraquat and diquat): HPLC

Amino acid type herbicides (glyphosate and glufosinate): HPLC

Organophosphorus pesticides (MEP, DDVP, malathion and others): GC/MS

5 Metals

Atomic absorption spectrometry (in cooperation with the Department of Public Health)

Screening tests at the emergency rooms

It is, of course, necessary to estimate a toxin by careful monitoring of symptoms of a patient, such as miosis in case of organophosphorus pesticide poisoning; but actual screening tests at the emergency rooms for causative toxins are also very useful It seems important to simply detect alcohol and carbon monoxide, at a clinical scene for rapid and suitable treatments,

groups of drugs; an important information can be obtained by this method especially for an

established for each drug in the kit; positive results can be obtained at levels higher than the cutoff values It does not require any pretreatment and enables tentative bedside diagnosis of the presence of a drug Although it is very useful at emergency rooms, it suff ers from the inabil-ity of detecting bromisovalum, phenothiazines and acetaminophen, which are very common

in poisoning cases in Japan; the simple kits using immunoassays for the above drugs are being eagerly awaited

Especially for pesticide poisonings, their prognosis is markedly aff ected by a method

of treatment to be made at the early stage of poisoning; an suitable treatment is necessary

organophosphorus and amino acid type herbicide groups are very important, because of

hydrosulfi te For organophosphorus pesticides, the clinical fi ndings, such as miosis and lowered levels of serum cholinesterase activity, are useful as indicators of their poisoning;

a simple color tests using 4-(4-nitrobenzyl)pyridine and tetraethylenepentamine is also avail-able for the pesticides For amino acid type herbicides, a TLC method with a ninhydrin color spot test can be used; its procedure is relatively complicated and a simpler test is being awaited

Confirmatory tests and quantitation at the laboratories

of Department of Legal Medicine

test, because immunoassays sometimes give false positive results for similar compounds In addition, the cross reaction usually takes place among compounds of the same group When the Triage kit shows a positive result for OPI, discrimination among heroin, morphine, codeine

because dihydrocodeine is usually contained in over-the-counter drugs of antitussives and cold medicines and is not illicit 6-Acetylmorphine is considered to be an indicator of heroin use; but there is a possibility that morphine has been prescribed for treating pain of a cancer

view

Aft er detecting a drug (group) by the Triage kit, mass spectral measurements are most

GC/MS and LC/MS in this section

GC/MS

screening are useful for selection of a derivatization method most suitable Most drugs can be confi rmed by GC/MS aft er derivatization; GC/MS is indispensable for analysis of illicit opiates and amphetamines

and 3,4-methylenedioxyamphetamine ( MDA) were identifi ed by GC/MS in a urine specimen

( > Fig 8.1), which had shown a positive result for amphetamine by Triage [12] Th e retention times and mass spectra of the peaks coincided well with those of MDMA and MDA; however, methamphetamine and amphetamine could not be identifi ed In this case, it was fortunate that the Triage test was positive, which enabled us to identify these compounds, because the reac-tivity of Triage with MDMA is relatively low; the reaction color can be observed only at more than 3,500 ng/mL of MDMA levels If the Triage test was negative, MDMA and MDA had been overlooked

According to the allegation of a poisoned patient, she had ingested a large amount of Tylenol

However, at the laboratories of Department of Legal Medicine, acetoaminophen could not be

illicit drugs are involved, the allegation of patients is usually not trustworthy; the medical team should be cautious about it and act at their own discretion

LC/MS

using LC/MS for benzodiazepines and sildenafi l citrate (Viagra) Screening of benzodiazepines

by Triage is a problem, because the cutoff level of the drug group is as high as 300 ng/mL; the

short time aft er its intake, resulting in a negative result is the Triage test

forced us to make a hard work for analysis In this case, the Triage test was negative; thus a tedi-ous procedure of urinary screening by GC/MS [14] was adopted, but it gave negative results Finally, the blood of the victim was analyzed by LC/MS; surprisingly high concentrations of triazolam, brotizolam and 1-OH-triazolam could be detected and identifi ed, and their blood

a new sensitive screening method, which can detect low levels especially of benzodiazepines

In the confi rmatory tests of paraquat, the survival curve proposed by Proudfoot et al [17]

is still being valid; it is useful for estimation of prognosis of the poisoning It is possible to

useful for poison diagnosis, especially when a poisoned patient survives for more than a week,

paraquat can be known by hair analysis

TICs and mass spectra of TFA derivatives of 3,4-methylenedioxymethamphetamine ( MDMA) and 3,4-methylenedioxyamphetamine ( MDA) obtained from urine of a patient and from the

respective standard compounds Right panels: TIC and mass spectra obtained from the urine

extract of a patient; left panels: those obtained from the authentic standards The identities of

MDMA and MDA were confirmed by the coincidence of the retention times and by the same

mass spectral profiles.

⊡ Figure 8.1

⊡

In this chapter, the author has mainly dealt with poisoning by drugs and mentioned some problems encountered in our actual activities of toxin analysis Recently, various kinds of drugs have become obtainable using the Internet; the consolidation of our analytical system is re-quired to be able to cope with such new compounds

Perspectives

Securing of the standard compounds for analysis in poisoning

For the fi nal identifi cation and quantitation of toxic compounds, their standard (authentic) compounds of high purities are absolutely necessary; without them, reliable analysis cannot be achieved When the target to be analyzed is a substance controlled by our Government, the

are many foreigners working or studying in Japan; there is a possibility of occurrence of poison-ing incidents uspoison-ing drugs or poisons which had been brought to Japan by foreigners When the pure compound of such a target to be analyzed is not available in Japan and also the compound

standard compound In U.S.A and Europe, small amounts of controlled substance standards are being freely transported for analytical purpose; easing of import of controlled substance stand-ards should be realized for analysts and researchers as soon as possible in Japan

Checking of the reliability of analytical methods

of the values seems sometimes inadequate For example, even in a suicidal case with a tricyclic antidepressant, the Triage test was negative for the drug in urine; however high concentrations

benzodi-azepine poisoning Such limitation of the Triage test should be kept in mind

In Japan, any third-party institution is unfortunately not available for quality assurance of analysis of toxic compounds or for assessment of analytical data [19]; the third-party

institu-⊡ Table 8.1

Cutoff values (ng/mL) of the Triage® kit

COC Cocaine (benzoylecgonine) 300

THC THC (11-non-∆ 9 -carboxylic acid) 50

TCA Tricyclic antidepressants 1,000

tion or a specialized committee of a scientifi c society dealing with quality control of the analy-sis should be established as soon as possible

Support and management of the analytical system

Apart from analytical methods and techniques, the author wants to mention the fi nancial as-pects for the support and management of the analytical system Many of analytical instruments are very expensive; the maintenance of various components of instruments, such as vacuum pumps and nitrogen gas generators, together with that of the main bodies of instruments, is also expensive Financial support is also required for keeping 24-hour analysis; for the purpose,

ana-lytical skill; the establishment of educational institutions special to toxin analysis is awaited Only aft er solving all of the above problems, the genuine analytical system for drugs and poisons will be established in Japan

References

1) Hayashida M (1983) Analysis of acute poisoning patients admitted to Critical Care Medical Center, Nippon Medical School during the past 7 years Jpn J Legal Med 37:227–235 (in Japanese with an English abstract) 2) Hayashida M, Nihira M, Watanabe T (1990) Application of a computer-assisted high-performance liquid chro-matographic multi-wavelength ultraviolet detection system to simultaneous toxicological drug analyses J Chromatogr 506:133–143

3) Nihira M, Hirakawa K, Hayashida M et al (1990) Rapid analysis of organophosphorus pesticides using 31 P Fou-rier transform nuclear magnetic resonance spectroscopy (FT-NMR) Jpn J Legal Med 3:57–62 (in Japanese with

an English abstract)

4) Hayashida M, Nihira M, Moriya N et al (1992) An evaluation and standardization of TOXI-LAB® test for emer-gency drug screening Jpn J Toxicol 5:251–265 (in Japanese with an English abstract)

5) Hayashida M, Ohno Y, Nihira M et al (1996) Severity index in traffic accident trauma and blood alcohol concen-tration Res Prect Forensic Med 39:307–316 (in Japanese)

6) Inuzuka S, Hayashida M, Nihira M (1997) Study on the situation of drug use and usefulness of rapid drug screen-ing at the critical care medical center J Nippon Med Sch 64:344–352 (in Japanese with an English abstract) 7) Nihira M, Hayashida M, Ohno Y et al (1997) Evaluation of the use of Triage®, a simple screening kit for drugs in urine, for emergency patients Rinshokensa-kiki Shiyaku 20:519–525 (in Japanese)

8) Nihira M (1998) Drug abuse and toxicological scene in Japan J Toxicol Sci 23(Suppl II):201–204

9) Yoshioka T, Kohriyama K, Ueki M et al (1999) A proposal on a guideline for analysis of toxic substances Jpn J Toxicol 12:437–441 (in Japanese)

10) Nihira M, Hayashida M, Ohno Y et al (1998) Urinalysis of body packers in Japan J Anal Toxicol 22:61–65 11) General study group on analysis of drugs in biological specimens (Ministry of Health and Welfare of Japan) (1995) Forum on Analysis of Drugs in Biological Specimens 1994 Tokyo, p 113 (in Japanese)

12) Nihira M, Hayakawa M, Yamada T et al (2002) Analysis of MDMA and PCP by GC-MS from patients admitted to the critical care medical canter Jpn J Toxicol 15:47–52 (in Japanese with an English abstract)

13) Nihira M, Hayashida M, Ohno Y (2001) Toxicological analysis for samples obtained at the Advanced Critical Care Medical Center of Nippon Medical School Jpn J Forensic Toxicol 19:195–205 (in Japanese with an English abstract)

14) Japanese Society of Legal Medicine (ed) (1999) Manual for Forensic Toxicology Analysis of the Japanese Society

of Legal Medicine Tokyo, pp 14–15 (in Japanese)

15) Baselt RC, Cravey RH (eds) (2000) Disposition of Toxic Drugs and Chemicals in Man, 5th edn Chemical Toxicology

16) Saito T, Takeichi Y, Yukawa N et al (1997) A case of homicidal poisoning involving several drugs J Anal Toxicol 21:584–586

17) Proudfoot AT, Stewart MS, Levitt T et al (1979) Paraquat poisoning: significance of plasma-paraquat concentra-tions Lancet 2:330–332

18) Scientific study group of Ministry of Health and Welfare of Japan (2000) Studies on Hair Analysis for Prevention and Clarification of Causes of Drug Poisoning Harms by Medicines and Pesticide Poisoning Tokyo, pp 147–172 (in Japanese)

19) Akahori F (2000) Toxicologists authorized by the Japanese Society of Toxicology Jpn J Toxicol 13:275–278 (in Japanese)