The table below is intended to help you decide what type of
anaesthetic might be most suitable for a given surgical procedure.
Suitable anaesthetic techniques for different types of surgery
Type of surgery Suitable anaesthetic technique
l Major head and neck General tracheal
l Upper abdominal
l Ear, nose and throat
l Upper limbs General tracheal (LMA)
or Nerve block
or Intravenous regional
l Lower abdominal General tracheal
l Groin, perineum or Spinal
l Lower limbs General tracheal (LMA)
or Nerve or field block
or Combined general and conduction
For minor emergency operations when the patient probably has a full stomach,
such as the suture of a wound or manipulation of an arm fracture, conduction
(regional) anaesthesia is probably the wisest choice.
For major emergency operations, there is often little difference in safety between
conduction and general anaesthesia.
It is a dangerous mistake to think that conduction anaesthesia is always safe.
When you have come to a decision on the most suitable technique, discuss it with
the surgeon and surgical team, who may give you further relevant information.
For example, the proposed operation may need more time than can be provided by
the technique you have suggested or the patient may need to be placed in an abnormal
position. Also check that you have all the drugs and equipment you may need.
You will probably have to decide on one of the following techniques:
anaesthesia with drugs given intravenously or by inhalation
anaesthesia with intramuscular ketamine
block (conduction anaesthesia)
There are advantages in combining light general anaesthesia with a conduction
block: this technique reduces the amount of general anaesthetic that the patient
requires and allows a rapid recovery, with postoperative analgesia being provided
by the remaining conduction block.
PLANNING GENERAL ANAESTHESIA
For general anaesthesia, tracheal intubation should be routine, unless there
is a specific reason to avoid it (see Figure 13.12 on
Tracheal intubation is the most basic of anaesthetic skills and you should be
able to do it confidently whenever necessary. In smaller hospitals, most of the
operations are emergencies; the lungs and lives of the patients are in danger
if you do not protect them by this manoeuvre.
Remember that all relaxants are contraindicated prior to tracheal intubation
if the patient has an abnormality of the jaw or neck or if there is any other
reason to think that laryngoscopy and intubation might be difficult (see also
Paediatric emergency anaesthesia, pages 14–18 to 14–20).
Safety of general and conduction techniques
There are potential risks with all types of anaesthetic. These can be minimized
by careful assessment of the patient, thoughtful planning of the anaesthetic
technique and skilful performance by the anaesthetist. You should keep records
of all the anaesthetics that you give and regularly review complications and
morbidity. Some of the possible complications to look for are listed below.
CHOICE OF TECHNIQUE IN EMERGENCY ANAESTHESIA
General or regional anaesthesia?
General and regional techniques both have a place in dealing with emergencies.
The factors that favour the use of general anaesthesia are:
about the diagnosis and length of operation
distress or confusion.
are exceptions. For emergency caesarean section, spinal anaesthesia
may be better, provided the mother is not shocked, septic
or dehydrated. A strangulated inguinal hernia or torsion
of the testis occurring in a patient in good general condition
can also be performed under spinal anaesthesia.
On the other hand, cord prolapse during labour, shock or severe bleeding indicates
In some cases, either general or regional (spinal) anaesthesia may be appropriate:
of abscesses or other septic conditions.
gunshot wound to the leg, when there is uncertainty about
what will be found, would be better explored under general
anaesthesia. A few days later, the same patient returning
in a stable condition for wound toilet, could have a spinal
Full stomach and regurgitation risk
As a general rule, all patients must come to the operating room starved (no solids
for 6 hours, water allowed up to 2 hours preoperatively). You should assume that
the stomach is not empty in injured or severely ill patients, in those that have
received an opiate such as pethidine and in pregnant women.
Any method of anaesthesia, including awake techniques, can have an unexpected
reaction that can, in theory, lead to unconsciousness, regurgitation and aspiration
of stomach contents. You will need to judge each case on its merits, balancing
the risk of regurgitation and aspiration against the risks of general or spinal
anaesthesia. The general condition of the patient determines the risk of regurgitation
more than the choice of technique. If an operation is postponed on the grounds
that the patient is not starved, there may be a risk of it not being carried
out at all.
Poor risk cases
A typical case where we are unsure of what method to use might be a patient in
poor condition whose chronic illness has been neglected. Surgery may give improvement
by cleaning, debridement of necrotic tissue or drainage of pus in the hope that
healing will take place, suffering will be relieved and the patient will move
a step nearer to leaving hospital. Large numbers of such patients are seen every
day in hospital operating rooms in any country with a high rate of HIV seroprevalence.
Obstetric sepsis has a high incidence and is the biggest cause of hospital maternal
mortality in some countries. Patients frequently develop sepsis up to ten days
following septic abortion, ectopic pregnancy and normal or operative delivery.
Sometimes, in advanced sepsis, there are disagreements among medical staff about
whether to take the case at all.
“Gasping” means a type of respiration with feeble, jerky inspiratory
efforts that cause movement of the head in a semiconscious patient. Prognosis
is very poor. Predicting the outcome with or without an operation is one
of the more difficult judgements in medical practice.
Ketamine is the drug of choice, 1–2 mg/kg IV, according to the condition.
Oxygen is mandatory after ketamine because hypoxia usually occurs.
Intubation is recommended for laparotomy. A small abdominal incision and drainage
may become a full laparotomy and washout in the intensive care unit. Management
with inotropic support is usually needed postoperatively.
A critical moment in the operation is during the initial abdominal exploration
and breaking down of adhesions. Endotoxaemia is maximal at this time and sudden
death in asystole may occur. Epinephrine should be drawn up ready.
Ketamine is safest for patients who are to have uterine evacuation, where there
has been haemorrhage or sepsis.
SPECIAL ANAESTHETIC ISSUES
The solo practitioner giving anaesthesia
Many hospitals in developing countries will have only one person assigned or
trained to give anaesthesia. Even so, you should identify and train another person
to help you and even take over your duties from time to time. It is quite possible
for a single-handed paramedical health worker to have sole responsibility for
a major emergency case in a remote location in a developing country that would,
elsewhere, have a team of senior experts managing the different requirements
of airway, drip, drug administration, ventilation, etc. It is also possible for
you (if you are a solo, non-specialist practitioner) to do just as good a job
as the experts.
However, there are certain things that require the help of a second person:
a struggling or distressed trauma patient during induction
some vital bit of equipment, especially in emergency
to a problem with the sucker.
is important for you to identify an assistant (not a replacement
anaesthetist) who knows the hazards of anaesthesia, how you
work and where things are kept. Above all, he or she needs
to understand the meaning of acting quickly when things go
Never start a case if you are alone with the patient in the operating room.
The full stomach: cricoid pressure
A full stomach is one of the most dangerous situations in the practice of anaesthesia:
if a patient aspirates stomach contents into the lungs, the resulting complications
mean that the chance of survival will be slight. Aspiration of stomach contents
may be one of the most common causes of death on the operating table in developing
Cricoid pressure (pressing on the cricoid cartilage with a pressure of 30 Newtons:
3 kg) is intended to prevent passive regurgitation, but will not stop active
vomiting. Active vomiting probably means the patient is awake and has intact
protective reflexes; cricoid pressure is therefore not appropriate.
There are two situations where cricoid pressure should normally be applied:
for all emergency surgery
caesarean sections performed under general anaesthesia.
are additional dangerous situations where regurgitation is
section for prolonged obstructed labour, compounded by
ruptured uterus, hypovolaemic shock or sepsis, especially
where local (herbal) medicines have been given
patient who has a hiccup
patient who coughs, strains or otherwise moves a lot
at the moment of attempting to intubate, especially after
inhalation induction with no muscle relaxant
patient with stomach filled with air during mask inflation
of the lungs due to poor mask-holding technique
debilitated patients with chronic gastrointestinal disease.
it has never been subjected to controlled trials to prove
its efficacy, properly applied cricoid pressure is believed
to be an effective measure to prevent regurgitation.
If in doubt about the regurgitation
risk, apply cricoid pressure – it
costs nothing and may save a life.
Spontaneous versus controlled ventilation (IPPV)
Except for neurosurgery, there is no evidence that any operation has a better
outcome when controlled ventilation is used instead of allowing the patient to
breathe spontaneously. Thoracic procedures involving the open chest cannot, of
course, be performed without controlled ventilation as the normal mechanics of
breathing requiring negative pressure in the pleural cavity are disrupted.
The shocked patient may suffer a significant reduction in cardiac output if Intermittent
Positive Pressure Ventilation (IPPV) is applied, owing to the increased thoracic
gas pressure preventing venous return to the heart. Overzealous IPPV, either
by hand or ventilator, may be a terminal event in a patient with hypovolaemia.
The use of spontaneous breathing has an additional safety effect of allowing
you to monitor cerebral perfusion: breathing will stop if the brain is not being
perfused with blood at an adequate pressure. Also, overdose of volatile agent
in a spontaneously breathing patient is unlikely.
Where facilities for anaesthesia are limited, ventilators often do not have alarms
to warn about disconnection and trained, experienced anaesthetists are not available.
Emergency surgery under general anaesthesia in these conditions is safer when
performed with the patient breathing spontaneously.
Ventilation in chest and head injuries
The patient with combined chest and other trauma may require intubation as part
of general anaesthesia for a laparotomy (such as in cases of a ruptured spleen)
or craniotomy (in cases of extradural haematoma). Intermittent Positive Pressure
Ventilation (IPPV) is not necessarily part of the early management of chest trauma
unless there are specific indications, for example, during cardiopulmonary resuscitation
or if hypoxia, respiratory failure or other deterioration occurs.
Rib fractures may cause the lungs to be punctured on sharp ends inside the chest
and result in pneumothorax. With further gas being forced into the lungs during
ventilation, the pneumothorax may become a tension pneumothorax. A chest drain
should be in place.
Lung contusion (consolidation from damage and bleeding) often gets worse in succeeding
days so a patient who is comfortably breathing and sitting up with an oxygen
mask on the first day post-trauma may later deteriorate and have to be ventilated.
Patients with head injuries can benefit from IPPV in the early stages of admission;
it will help to avoid the lethal combination of hypoxia, airway obstruction and
hypercarbia, a significant cause of mortality in the immediate period after injury.
However, controlled ventilation itself has not been shown to improve outcome
for the head injured patient. There is no point in ventilating a brain dead patient
with no prospect of recovery.
Tracheal tube versus laryngeal mask airway
The laryngeal mask airway (LMA) is now commonplace in most countries. It has
proved very popular and is far less stimulating to the patient than the tracheal
tube. It should not be used to replace intubation for:
section under general anaesthesia
situation where there is a regurgitation risk (all emergencies).
can be under deep halothane anaesthesia or, in a paralysed
patient or after intravenous induction, with propofol. Do not
try LMA insertion after thiopentone as the patient will gag.
Method of insertion
the head extended and mouth open, pass a deflated, lubricated
LMA over the tongue and push it up against the soft palate
until it comes to rest against the upper oesophageal
sphincter and epiglottis. The end point is quite distinct.
It must not push the tongue in front of it.
the cuff. A correctly inserted LMA will then move about
5 mm back out of the mouth from its original position.
the circuit and check for breathing.
LMA has been used with success to maintain the airway after
failed intubation. This important role of the LMA as an emergency
tool in airway management makes it an essential piece of
equipment in the operating room in any country in the world.
In emergency induction of anaesthesia, it may be convenient to use drugs mixed
together in the same syringe for speed and simplicity of administration and increased
patient safety. Ketamine and suxamethonium mix well without interaction and give
a convenient, reliable one-shot sleep and relaxation effect, of rapid onset,
so that you can concentrate on the airway. This is especially valuable if your
syringes and needles are of poor quality, are made of glass or have been resterilized.
However, many drugs do not mix, notably thiopentone and suxamethonium. Diazepam
does not mix well with other drugs.
Pre-oxygenation should be done with one hand holding the mask and the other giving
the drugs. If two hands are needed for the drugs, the mask can be held by the
patient or an assistant.
Good suction is of paramount importance in anaesthesia and resuscitation and
for all forms of surgery and intensive care. As a resuscitation tool, suction
comes second only to a self-inflating bag and mask.
When you need suction, it must be instantly available, right by your hand at
sucker must be ready and switched on for any case where
a full stomach is suspected or where the airway is being
inspected, such as when you are looking for a foreign
body or other obstruction
sucker must be ready, but can be turned off, for elective
power of suction is important. Never believe that a sucker
is working until you have raised the tip to your ear and
heard its power. Then tuck it under the pillow or mattress
ready for use. Make sure the suction tubing will not kink
when angled and that the suction motor is protected by a reservoir
bottle and a filter.
A foot-operated sucker can be a life saving piece of equipment at a health centre
Sucking stimulates the gag reflex and may induce vomiting. Excessive sucking
damages the mucosa and causes bleeding. The general rules of suction are:
not suck when going in, especially if you cannot see
the sucker tip
suck as much as is needed: that is, when you can hear
and see something coming
the sucker moving and continue sucking on the way out
routinely extubating a patient:
– Always suck both sides of the tube
– With the tip at the larynx, let the cuff down
– When the time is right for extubation, re-insert the sucker
– Remove the tube first then, just afterwards, remove the sucker, sucking
all the while.
Use a rigid sucker for emergencies.
Suction in the trachea
A small-bore soft sucker is used for tracheal or bronchial suction. Special precautions
are needed if sucking in the trachea: the sucker should be sterile, not the same
one as used for the pharynx.
In children, the sucker should not be a tight fit in the small tracheal tube,
otherwise the negative pressure may cause lung collapse.
Repeated tracheal suction in the intensive care unit may cause bradycardia and
even cardiac arrest, so the ECG monitor must be watched.
Removal of foreign bodies
Removal of foreign bodies is a common job for anaesthetists
in developing countries. In a district hospital, it is important
that the anaesthetist is able to remove objects in the mouth,
airway or pharynx, with or without anaesthesia, using Magill’s
forceps. Children often hide small coins in their mouths
which may slip down into the pharynx.
Have a recent X-ray, if available. After inhalation induction with halothane,
a long straight blade laryngoscope is best to go behind the larynx. The child
will be apnoeic during pharyngoscopy, so a pulse oximeter should be connected.
An object further down in the oesophagus may be out of reach and may require
intubation and oesophagoscopy.
An assortment of other items may have been inhaled or become lodged in the upper
airway: seeds, fish bones, chicken bones, peanuts, bits of plastic, bottle tops
and even leeches. For the airway, there are three general situations:
airway obstruction with an object caught at the larynx
smaller foreign body further down in the trachea or bronchi.
first is obviously very rarely seen in a hospital. If you
witness the event, there are two courses of action.
Heimlich manoeuvre. Stand behind the patient, give a
sharp upward thrust into the epigastrium (round the front)
with both fists to raise intrathoracic pressure and expel
that fails, puncture the cricothyroid membrane with a
sharp knife and insert a plastic biro tube as a laryngostomy.
The object partly blocking the larynx is often a piece of
bone or something flat, irregular and sharp that can be easily
removed with Magill’s
forceps after inhalation induction with halothane and
oxygen. There is intense irritation for the patient and stridor
may be caused by laryngospasm as well as by the object
itself. Inhalation induction may be slow and, if assisted
ventilation is easy, it may be permissible to give suxamethonium
and IPPV. Though theoretically this may push the object further
down, in practice that rarely happens. Do not declare
the job complete until you are sure everything has been removed
and breathing is comfortable and silent.
Unfortunately, the commonest situation is for a seed or peanut to be inhaled
by a child past the cords and into a bronchus. Referral to a centre with a ventilating
bronchoscope is mandatory and urgent.
a suitable anaesthetic technique that fits in with
the patient’s condition, the
needs of the surgeon and your own experience and skill
cases in district hospitals are full-stomach emergencies,
so general anaesthesia will normally require protection
of the lungs with a tracheal tube.