Effects of alcohol

Question 1

20mg/100ml of blood (1 unit)

Answer 1

-disinhibition, euphoria, emotional insatbility, release of social and sexual inhibitions

Question 2

80mg/100ml of blood

Answer 2

-more pronounced previous effects, motor coordination becomes more affected, marked effect on judgement

Question 3

200mg/100ml of blood

Answer 3

-motor coordination is progressively lost and speech becomes slurred

Question 4

300mg/100ml of blood

Answer 4

unconsciousness

Question 5

400mg/100ml of blood

Answer 5

death from respiratory failure

Question 6

Pharmacokinetics of alcohol

Answer 6

• rapidly absorbed from mouth, lung, stomach, small intestine (peak blood conc. in 30-60minutes)
• cleared from the body mostly by metabolism (liver)

Question 7

Alcohol dehydrogenase (ADH)

Answer 7

CH3CH2OH + NAD+ –> CH3CHO + NADH

Question 8

Clearance

Answer 8

• Zero order with respect to ethanol

- ethanol cleared at constant rate regardless of concentration therefore easy to calculate

Question 9

Detection of alcohol in breath

Answer 9

Breath intoximeter - IR/EC detection of alcohol in expired air
Detects mouth alcohol and interfering substances

Question 10

Detection of alcohol in blood

Answer 10

• Gas chromatography of extracted blood sample with IR/EC detector
• eliminates cross detection of other substances

Question 11

Road traffic Act 1988

Answer 11

Section 4 (i) 
driving a motor vehicle whilst unfit through drink or drugs
Section 4 (ii)
being in charge of a vehicle whilst unfit through drink or drugs

Question 12

Forward and Back calculation of alcohol conc

Answer 12

NEED

• height and weight of subject
• amount of alcohol consumed
• when alcohol consumed (start time)
• Intoximeter and/or blood sample readings
• what times values needed for

Question 13

Procedure -alcohol

Answer 13

• police stop suspect
• detect alcohol (smell)
• roadside breath test
• if positive -arrest
• intoximeter procedure
• if <40 release without charge
• if >50 charge
• if 40-50 - take blood/urine sample

Question 14

Lines of defence (Section 5 - alcohol)

Answer 14

• statutory defence - no intention to drive - need calculation of when subject would fall below statutory limit
• post incident drinking - need calculation to verify consistency of evidence

Question 15

Section 5 (Alcohol) cont,

Answer 15

Spiked drinks - calculations required to verify evidence

Question 16

MEDICAL IMPACTS OF ALCOHOL

Answer 16

Types of death involving alcohol:

• acute intoxication
• chronic alcoholism
• accidents
• suicides
• homicides

Question 17

post mortem examination

Answer 17

-history, external, internal, samples (N.B. Femoral artery/vein)

Question 18

Acute alcohol intoxication

Answer 18

• > 300mg/100ml blood = increasing danger of death
• direct respiratory depressant effect on the brainstem
• aspiration of vomit
• cardiac arrhythmia
• trauma
• fire deaths
• drowning

Question 19

Post mortem findings

Answer 19

• usually only congestion of the lungs
• vomit in airways
• evidence of chronic alcoholism
• pre-existing disease
• traumatic injury
• burns?

Question 20

Chronic alcoholism

Answer 20

• extremely potent drug
• all systems of body are affected
• bulbous nose
• bruises
• jaundice/spider naevi/gynaecomastia
• ascites/oedema

Question 21

jaundice

Answer 21

• accumulation of bilirubin in the skin
• breakdown product of haemoglobin (Hb)
• damaged liver cells (hepatocytes) do not function adequately

Question 22

Ascites

Answer 22

• accumulation of fluid in the abdominal cavity

- due to portal hypertension and decreased proteins in blood (albumin esp.)

Question 23

spider naevi

Answer 23

• skin lesion
• small central blood vessel with radiating smaller vessels
• affects the face, chest and upper limbs
• sign of chronic liver disease

Question 24

Internal - C.N.S

Answer 24

• intracranial bleeding
• cerebellar atrophy
• wernicke-korsakoff psychosis (nystagmus, ataxia, amnesia, confabulation, hallucinations)
• delerium treatments

Question 25

Intracranial bleeds

Answer 25

• subdural haemorrhage
• extradural haemorrhage
• intracerebral haemorrhage

Question 26

extradural haemorrhage

Answer 26

• space between skull and dura
• skull fractures (site? vessel?)
• lucid interval
• neurosurgical drainage is necessary

Question 27

subdural haemorrhage

Answer 27

below the dura

Question 28

intracerebral haemorrhage

Answer 28

• increased risk of haemorrhagic stroke if clotting is abnormal and the vessels are inherently weakened
• increased risk of hypertensive stroke

Question 29

Internal - cardiovascular system

Answer 29

• increase in blood pressure

- alcoholic cardiomyopathy (dilated chambers, enlargement of the cardiac myocytes, patchy fibrosis in the interstitium)

Question 30

Internal - gastrointestinal system

Answer 30

• gastric ulcer/gastritis
• mallory-weiss tear
• pancreatitis (acute/chronic)
• malabsorption

Question 31

Pancreas

Answer 31

• “dual purpose” gland
• endocrine portion :Islets of Langerhans (Hormones: Insulin, glucagon, somatostatin)
• exocrine gland: 99% of pancreas, many digestive enzymes, bicarbonate ions

Question 32

Pancreatitis

Answer 32

• direct toxic effects
• acute - pain/nausea/vomiting/metabolic/shock/death
• acute - haemorrhagic / necrotic pancreas
• chronic - pain/weight loss/malabsorption / diabetes
• chronic -fibrotic

Question 33

Internal examination - LIVER

Answer 33

• alcoholic hepatitis
• fatty degeneration (enlarged smooth liver)
• cirrhosis (Fibrous bands, nodules, 60-70% of Western world due to alcoholism)
• portal hypertension (restriction of blood flow, increased B.P., back pressure - dilated veins, oesophageal varices)
• liver failure

Question 34

Portal hypertension (liver)

Answer 34

• Splenomegaly
• ruptured varices
• haematemesis
• black stools
• haemorrhage - can be fatal