Adam's regulatorPressure reducing valve
at anaesthetic machine gas outlet (12 psi).
Adjustable Pressure Limiting Valve
relief valve, to protect patient's lungs against high breathing gas pressures
during spontaneous breathing.
Loss of sensation, to relieve the patient from
awareness, pain, or muscle control.
| Epidural||Injection of a local
analgesic into the epidural space, blocking the spinal nerves.
|General||Unconsciousness induced by inhalational, IV, or a
combination of both techniques.|
|Local||Localised application of topical or injected analgesic.|
| Regional||Typically, an analgesic blocks
sensation to a complete limb.|
| Spinal||Injection of local anaesthetic into
the cerebrospinal fluid of subarachnoid space around the lower spinal nerves.|
| TIVA||Total Intravenous Anaesthesia|
The general guidance
for pre-use checking of anaesthetic machines is mandated by the
specific procedures set by the particular manufacturer.
Drug (eg, Neostigmine, Distigmine, Pyridostigmine) which inhibits acetylcholinesterase,
preventing it from metabolising acetylcholine. Result is increased levels of
acetylcholine, with consequent reduction of muscular block from agent, such as
Atracurium. Also prolongs action of Suxamethonium. Has muscarinic side-effects,
which are antagonised by Atropine.
AnticoagulationUsing a drug to reduce the chance of a blood clot
forming, such as when helping to prevent a stroke from occurring. Commonly used
anticoagulant drugs are Heparin and Warfarin.
Drug to relieve nausea/vomiting, often caused by
agents, such as opioid analgesics and nitrous oxide.
Drugs, such as Atropine and Glycopyrronium, which reduce
muscarinic effects of Neostigmine, and prevent bradycardia and hypotension
associated with Halothane, Propofol, and Suxamethonium. Also, drugs which reduce
intestinal motility eg, in management of irritable bowel syndrome.
AntispasmodicRelieves/prevents muscle spasms.
American Society of Anaesthesiologists rating
scheme for the physical state of a patient.
|I||Normally healthy individual
|II||A patient with mild systemic disease|
|III||A patient with severe systemic disease which is not
|IV||A patient with incapacitating systemic disease which is a
constant threat to life|
|V||A moribund patient who is not expected to survive 24 hours
with, or without, an operation|
|E||Added as a suffix for emergency cases|
AuscultationListening to internal organs.
BarbituratesGroup of sedative and hyponotic drugs,
such as Thiopentone and Methohexitone.
BarotraumaInjury due to excess pressure in tissues.
BenzodiazapinesDrugs used for sedation, anxiety relief,
muscle relaxation, anti-convulsive. For example: Midazolam, Oxazepam, Diazepam,
Lorazepam. Reversed by Flumazenil.
Beta (β) blockers
Negative inotropic drugs which block the
affect of Adrenaline on the heart and blood vessels, by weakening effects of
the Sympathetic Nervous System on heart conductivity, and reducing blood pressure
and heart rate. More
Bier blockIntravenous regional
anesthesia where an extremity, such as a leg, is made numb for surgery,
by injecting a local anaesthetic into a vein, after the blood has been
squeezed out of the extremity, and a tourniquet has been placed distal to
the surgical site. Typical anaesthetics used are 0.5% Prilocaine or 0.5%
Lignocaine. A typical adult dose for a leg is 50-60 ml, and 40 ml for an arm.
The tourniquet prevents the local anaesthetic from leaving the
extremity, and blood from entering it, giving the patient a numb extremity, and
the surgeon a bloodless field in which to work. The tourniquet should be inflated
to a pressure at least 50 mm/Hg above the patient's systolic blood pressure.
There is a time limit of 1-2 hours on the application of a tourniquet, due to
the oxygen starvation which occurs in the region which has an impeded venous
flow. If the tourniquet is released whilst a large amount of the anaesthetic is
yet to be metabolized, blood toxicity may result.
Transfusion of blood is governed by the Blood Safety and Quality Regulations (2005),
which describe all stages of transfusion,
from donation to patient adminstration. Problems with transfusion must be reported
according to the SABRE
Blood description and testing
A centrally inserted venous catheter to
provide intravenous administration - similar to a Hickman line.
A hollow needle, inserted into a central or
peripheral vein, to facilitate intravenous fluid administration.
cardiothoracic procedures, drug and venous access preparation is different from
other types of surgery. More
conversion of an arrhythmia
, such as
Atrial fibrillation, to a sinus (normal) rhythm, using an electrical defibrillator
or by pharmacological means.
Re-infusing a patient's
own blood, which has been salvaged during surgery.
Confidential Enquiry into Perioperative Deaths:
|1||Elective||Operation at time to suit Surgeon,Anaesthetist, and patient.|
|2||Scheduled||Operation within 24 hours. Delayed operation after resuscitation.|
|3||Urgent||Operation between 1 and 3 hours. Early surgery preferred, but not life saving.|
|4||Emergency||Operation within 1 hour. Immediate operation or resuscitation simultaneous
with surgical treatment.|
Intravenous fluids which help to support blood volume,
and will not cross semi-permeable membranes (unlike crystalloids), such as
capillaries, but will remain within the cardiovascular system.
Note: Colloids are not as good as crystalloids for correcting electrolyte
- Dextrans 40
- Dextrans 70
- Hydroxyethyl Starch
ComaUnconsciousness, where the patient cannot be aroused, has no
normal eye movements, and does not respond to stimuli, such as pain.
Offers the fast onset time of a Spinal
(sub-arachnoid block) anaesthetic, with the advantage of topping up offered by an Epidural
CrystalloidsIntravenous fluids which cross semi-permeable
membranes, thereby useful for correcting electrolyte imbalances.
Depolarising neuromuscular blockPersistent
depolarization of skeletal muscles, making the muscle fiber resistant
to further stimulation by acetylcholine.
DiureticAn agent, such as Furosemide, which increases urine
Drops per ml (millilitre) of fluid administration
Common drop factors...
- 10 drops/ml (blood)
- 15 drops/ml (blood)
- 20 drops/ml (crystalloid)
- 60 drops/ml (microdrop)
Drum Cartridge CatheterA method used in central vein cannulation.
The vein is cannulated with an introducer cannula. The needle is removed, and is replaced
by the drum cartridge catheter, which is left in place.
: outside the Dura Mater. In anaesthesia, the injection of a local
analgesic into the epidural space, to block the nerve routes from the spinal cord.
Used in procedures involving the lower limbs, pelvis, perineum and lower abdomen.
Also commonly used to alleviate pain in childbirth, usually started during labour,
and given before the neck of the womb has started to dilate.
Pre-operative fasting for elective surgery: Adults
: 2 hours for water;
6 hours for solids and milky drinks. Children
: 2 hours for water;
4 hours for breast milk; 6 hours for solids and other types of milk.
High pressure gas cylinders are
colour coded, for safety. The following colour coding will, eventually, be
superceded by a new EU scheme:
||Cylinder colour||Shoulder colour||Pin index|
|Air||Grey||Black & white||1,5|
|Entonox||Blue||Blue & white||Central|
Gas suppliesTypical supplies to a theatre are: Air, Oxygen, and
Nitrous Oxide, at a pressure of 400-500 kPa.
Hartmann's solutionColloid balanced salt solution, used
mainly for general extracellular fluid replacement. Contains calcium, chloride, lactate,
Health and Safety at Work Act
Imposes duties on employers and employees to protect all persons from harm, whilst at work,
and mandates requirements for Welfare at work.
A central line which allows intravenous
administration, and blood sampling. The line is inserted through a vein (neck or
chest), and tunnelled under the skin, to it's exit point at the shoulder or chest.
There will be 1-3 lumens.
Before leaving theatre,
patients destined for Intensive Care Units must be transported on special beds, which must
be checked for the following:
- Suction equipment
- Oxygen cylinder
- Monitoring equipment
- Mapleson C
- Ambu bag
Infusion pumpA machine which infuses fluids and medications
at a pre-determined rate. Can be used for IV, epidural, arterial, or subcutaneous
InotropicA substance which increases the force of muscular
contractions, particulary of the heart muscle.
Intraoperative Cell Salvage
Also known as autologous blood salvage; a medical procedure involving the recovery of
blood lost during surgery, and re-infusing it into the patient.
Equipment which delivers
intravenous fluids/drugs at a rate set by manipulation of a thumb wheel.
Minimum Alveolar Concentration (MAC)Minimum concentration
of an anaesthetic agent in the alveolus, at 1 bar pressure, which produces
no response in 50% of subjects exposed to a surgical stimulus.
A topical anaesthesia solution, which reduces
bleeding in ENT procedures.
|Agent ||Soution ||Volume |
|Adrenaline ||1:1000 ||1 ml |
|Cocaine ||10% ||2 ml |
|Na Bic. ||8.4% ||4 ml |
|Saline ||0.9% ||13 ml |
NaloxoneAn opioid antagonist, which counters depression
of the central nervous system, caused by opioids.
Nasogastric tubeA tube which is passed through the nose to the
stomach, allowing stomach contents to be drained into a bag. A nasogastric tube
weakens the effect of the gastrooesophageal sphincter, and makes regurgitation
of stomach contents more likely, shown by increased intragastric pressure. The
increase in pressure is the basis of vomiting, and may be decreased if the
intragastric pressure can be reduced. Do this by allowing the tube to drain freely,
so fluid moves up the tube to the bag.
Nerve blockInjection of a local anaesthetic agent
close to a peripheral nerve or nerve plexus.
Nerve stimulatorsAdminister electrical stimuli to peripheral
nerves eg, wrist ulnar. Strength in Coulombs (product of amps and seconds).
Typical current is 6 mA, over 0.2
mS, with resultant charge of 1.2
µC. Stimulus longer than 0.3 mS can produce
repetitive nerve or muscle stimulation. Less charge to deliver supramaximal
stimulus necessary when negative electrode placed distally.
muscle relaxant drugs compete with acetylcholine (ACh) molecules, released at
the neuromuscular junction, to bind with nicotinic receptors on the post
synaptic membrane of the motor endplate. These drugs block the action of ACh,
which prevents depolarisation/contraction of the muscle. These blocking agents
relax the diaphragm, abdomen, and vocal chords. The patient, therefore, will
require assisted ventilation during anaesthesia.
Muscle groups differ in their sensitivity to muscle relaxants; the ocular
muscles, which are responsible for moving the eyes, are the most sensitive,
followed by the muscles of the jaw, neck, limbs, intercostals, and abdomen. The
diaphragm is the least sensitive muscle, which is why patients undergoing
surgery sometimes hiccup or breathe, as an early sign that the relaxants are
wearing off. The reversal agent for the block is Neostigmine - an
Non Steroidal Anti-inflammatory drugs
Patient controlled anaesthesia
Intravenous infusion of analgesia, controlled by the patient, using a
, such as the Graseby pump.
Patient transfer to operating table
The priorities are...
- Manage the airway
- Monitor oxygen saturation
- Prevent nerve and pressure point damage
Peripherally Inserted Central Catheter
A peripherally inserted central catheter is an alternative
to a centrally inserted line, and
can be used for prolonged periods, to provide IV access and total parenteral nutrition.
The PICC is inserted into one of the large peripheral veins (near the elbow), such as the
cephalic, basilic, or brachial veins, and then advanced through increasingly larger veins,
towards the heart, until the tip rests in the distal superior vena cava or cavoatrial junction.
Precordial thumpAn attempt to interrupt an arrhythmia, such as
Ventricular Fibrillation or pulseless Ventricular Tachycardia, by making a
single strike, with the fist, to the centre of the patient's sternum. The thump
is only effective if made at the onset of a witnessed and monitored adverse
rhythm (VF/pVT), and a defibrillator is not immediately available. Latest
resuscitation guidelines de-emphasise use of the precordial thump.
Steps to take when assessing an unconsciousness
Order of steps
|Danger||Assess Dangers to yourself and casualties|
|Response||Use the Glasgow Coma Scale to ascertain the level of
|Airway||Examine the Airway for obstructions|
|Breathing||Look, listen, and feel for adequate respiratory effort.
Supplement with oxygen to correct hypoxia, if saturations are below 95%|
|Circulation||If a carotid pulse is not palpable, then
resuscitation should be commenced|
Rapid Fluid Infusion
The rapid intravenous introduction of fluids, such as saline or blood products, into
the haemodynamically unstable patient, with the aim of correcting hypovolaemia and
hypotension. Belmont manual
Anaesthesia affecting only a part of the body, typically a limb. Generally
involves the introduction of local anaesthetic to block the nerve supply to a
part of the body, such as a leg. Unlike general anaesthesia, patients may remain
awake during their procedure, resulting in reduced side-effects, and enabling
the surgeon to converse with the patient during the procedure.
Regional block types...
The anaesthetic agent may be given in two ways:
- Central eg, epidural and spinal (neuroaxial)
- Peripheral plexus eg, brachial plexus
- Peripheral single nerve
- Injection directly into a vein, which has it's venous flow impeded by a
- Intravenous continuous flow (Bier block), via
a catheter, eg, continuous peripheral nerve block.
Ring block (field block)Local anaesthetic infiltration
circling the surgical site, without injection into the site itself. The block
prevents nerve impulses from leaving the site when, for example, it is undesirable
to 'pullute' the site with the anaesthetic agent.
A more in
depth survey of the patient than the primary survey.
An agent which relieves tension and anxiety. Commonly
used sedatives are the Benzodiazepine anxiolytic agents:
These agents are antagonised by Flumazenil.
A method of introducing catheters and probes
- Puncture the vessel with a needle.
- Insert the Seldinger wire through the needle into the vessel.
- Remove the needle.
- Use the Seldinger wire as means of access to the vessel.
Spinal (subarachnoid) block
injection of anaesthetic agent, typically Diamorphine or 0.5% Heavy Marcaine
, into the intrathecal space and the
cerebrospinal fluid of the subarachnoid space, around the lower spinal nerves,
below L2, so as to avoid piercing the spinal cord.
A cannula placed between skin and muscle.
- Insert cannula at a 45° angle
- Ensure pectoral fin is flat against skin
- Press in wings to squeeze out needle
- Replace cap
- Aspirate at white cap with 10ml syringe - ensure no blood
- Refit white cap
- Apply clear Tegaderm dressing
An injection into the fatty layer between the skin and muscle. Subcut injections are
given because there is little blood flow to fatty tissue, and the injected medication
is absorbed more slowly. Some medications, which can be injected subcutaneously,
include growth hormone, insulin, and adrenaline.
of Suxamethonium, which means a patient may reverse from anaesthesia, but remain
mimic the effects of the sympathetic nervous system, and used in the treatment of
cardiac arrest and hypotension. More
SyncopeTemporary loss of consciousness.
A portable, battery operated device for mechanical subcutaneous delivery of a drug,
at a predetermined rate, and over a specific period. It's purpose is to achieve a steady
plasma concentration of the drug. Two commonly used syringe drivers are the Sims Graseby
MS26 and MS16A.
|MS26||Green||Delivery rate at mm per 24 hours|
|MS16A||Blue||Delivery at mm per hour|
Total intravenous anaesthesia (TIVA)
General anaesthesia using a combination of intravenous agents, but no inhalational
gases. A target controlled infusion device controls the dosages, typically consisting
Propofol and Remifentanil. Equipment
Transversus Abdominis Plane block
local anaesthetic block, to the anterior and lateral abdominal wall, to provide
A hollow hypodermic needle, very
slightly curved at the end, suitable for inserting epidural catheters.
Ultrasound guided continuous peripheral nerve block
substance which causes contraction of blood vessels, resulting in reduced blood
flow and increased blood pressure. Acts directly, or indirectly, on the
. Often used in resuscitation,
and to treat hypotension in surgical patients.
Perioperatively, Ephedrine and Metaraminol should always be immediately available.
Ephedrine has a faster onset than Metaraminol, but only lasts for about 10 minutes;
whereas Metaraminol lasts 20-60 minutes.
Ephedrine is safe for use in pregnancy, as it does not reduce placental blood flow.
Volatile anaesthetic agents
agents which are liquid at room temperature, but evaporate easily for administration
by inhalation. Colour coding