Drug Summaries – Humza Ibrahim
numbness of the tongue and perioral region,
Chapter 15 restlessness, paraesthesia (including sensations of hot
and cold), dizziness, blurred vision, tinnitus, headache,
Anaesthesia nausea and vomiting, muscle twitching, tremors, and
convulsions.
1 GENERAL ANAESTHESIA After injection of a bolus of local anaesthetic, toxicity
may develop at any time in the following hour. In the
Anaesthesia is induced with either a volatile drug event of signs of toxicity during injection, the
given by inhalation or with an intravenously administration of the local anaesthetic must be
administered drug; anaesthesia is maintained with an stopped immediately. In the event of local
intravenous or inhalational anaesthetic. Analgesics anaesthetic-induced cardiac arrest, standard
usually short-acting opioids, are also used. The use of cardiopulmonary resuscitation should be initiated
neuromuscular blocking drugs necessitates immediately. Lidocaine must not be used as anti-
intermittent positive-pressure ventilation. Following arrhythmic therapy.
surgery, anticholinesterases can be given to reverse
the effects of neuromuscular blocking drugs.
Antimuscarinic drugs are used (less commonly
nowadays) as premedicants to dry bronchial and
salivary secretions.
• Intravenous – Propofol, thiopental
• Inhalational – nitrous oxide, desflurane
• Analgesics – alfentanil, fentanyl, remfentanyl
• Neuromuscular blockers – suxamethonium
• Reversal of neuromuscular blockade -
neostigmine
• Antimuscarinics – atropine, glycopironium
2 LOCAL ANAESTHESIA
Benzocaines are the drug of choice; they block
conduction along nerve fibres. They vary in their route
of administration. Care must be taken to avoid
accidental intravascular injection; local anaesthetic
injections should be given slowly in order to detect
inadvertent intravascular administration.
Local anaesthetics cause dilatation of blood vessels.
The addition of a vasoconstrictor e.g. low
concentration adrenaline, to the local anaesthetic
preparation diminishes local blood flow slowing the
rate of absorption, and thereby prolonging the
anaesthetic effect (not advisable in digits or
appendages because of the risk of ischaemic necrosis).
Local anaesthetics should not be injected into
inflamed or infected tissues nor should they be
applied to damaged skin.
The systemic toxicity of local anaesthetics mainly
involves the central nervous and cardiovascular
systems. CNS effects include a feeling of inebriation
and light-headedness followed by drowsiness,
Chapter 15 – Pg 1
Compiled using the British National Formulary
numbness of the tongue and perioral region,
Chapter 15 restlessness, paraesthesia (including sensations of hot
and cold), dizziness, blurred vision, tinnitus, headache,
Anaesthesia nausea and vomiting, muscle twitching, tremors, and
convulsions.
1 GENERAL ANAESTHESIA After injection of a bolus of local anaesthetic, toxicity
may develop at any time in the following hour. In the
Anaesthesia is induced with either a volatile drug event of signs of toxicity during injection, the
given by inhalation or with an intravenously administration of the local anaesthetic must be
administered drug; anaesthesia is maintained with an stopped immediately. In the event of local
intravenous or inhalational anaesthetic. Analgesics anaesthetic-induced cardiac arrest, standard
usually short-acting opioids, are also used. The use of cardiopulmonary resuscitation should be initiated
neuromuscular blocking drugs necessitates immediately. Lidocaine must not be used as anti-
intermittent positive-pressure ventilation. Following arrhythmic therapy.
surgery, anticholinesterases can be given to reverse
the effects of neuromuscular blocking drugs.
Antimuscarinic drugs are used (less commonly
nowadays) as premedicants to dry bronchial and
salivary secretions.
• Intravenous – Propofol, thiopental
• Inhalational – nitrous oxide, desflurane
• Analgesics – alfentanil, fentanyl, remfentanyl
• Neuromuscular blockers – suxamethonium
• Reversal of neuromuscular blockade -
neostigmine
• Antimuscarinics – atropine, glycopironium
2 LOCAL ANAESTHESIA
Benzocaines are the drug of choice; they block
conduction along nerve fibres. They vary in their route
of administration. Care must be taken to avoid
accidental intravascular injection; local anaesthetic
injections should be given slowly in order to detect
inadvertent intravascular administration.
Local anaesthetics cause dilatation of blood vessels.
The addition of a vasoconstrictor e.g. low
concentration adrenaline, to the local anaesthetic
preparation diminishes local blood flow slowing the
rate of absorption, and thereby prolonging the
anaesthetic effect (not advisable in digits or
appendages because of the risk of ischaemic necrosis).
Local anaesthetics should not be injected into
inflamed or infected tissues nor should they be
applied to damaged skin.
The systemic toxicity of local anaesthetics mainly
involves the central nervous and cardiovascular
systems. CNS effects include a feeling of inebriation
and light-headedness followed by drowsiness,
Chapter 15 – Pg 1
Compiled using the British National Formulary
