Anesthesia
Certain diagnostic and therapeutic procedures may require anesthesia for restraint and prevention of pain. In most cases,
isoflurane gas, administered by mask is the simplest, safest, and most rapid method. Endotracheal intubation is difficult
and requires that the hedgehog be deeply anesthetized, so not recommended for novice clinicians. About 1.5-2 mm endotracheal
tube is needed for an adult hedgehog. Injectable anesthetics carry the inherent disadvantage of greater difficulty to control
depth of anesthesia. Hedgehogs loose much heat more rapidly, the tracheal lumen occludes more easily, the patient is more
difficult to monitor. A supplemental heat source is essential, and cotton tipped applicators should be available to swab out
the throat. A small endotracheal tube should be available for emergency intubation. Clear adhesive drapes facilitate monitoring.
Most importantly, a technician should be dedicated to the constant monitoring of the patient. The tidal volume is generally
too low to move the bag on most systems so respiration cannot be monitored in this way. The low tidal volume also leads to
a large amount of dead space within the delivery system. Semi-open, non-rebreathing systems must be used for hedgehogs. Special
bags are available that adjust to the small tidal volume. Alternatively, a balloon can be used as a bag on the non-rebreathing
circuits. A respiratory monitor helps detect early changes in respiratory rate or tidal volume. An ECG facilitates monitoring
well.
Surgery
Preparation of the surgical site can be a challenge if surgery is performed on the dorsal part of the body. The spines must
be removed so a surgical field can be formed. They can be plucked or clipped at the base. These spines are very difficult
to pluck. Clipping is done with a pair of scissors just at the base, leaving a little behind. The skin is then prepared as
in other animals. Surgery of hedgehogs can be enhanced by the use of several types of instrumentations not commonly used in
traditional pets. Their small size requires finer instruments, methods of controlling small amounts of hemorrhage, magnification
and directed source of light. Microsurgical or ophthalmic instruments are frequently used. Microsurgical instruments should
be counterbalanced and have rounded handles to allow them to be manipulated by gently rolling them between the fingers. There
should be no locking mechanism on needle holders as releasing these causes considerable jarring. Delicate surgery should be
performed while seated with the wrists supported on the table to minimize motion. Hemorrhage can be controlled by the use
of electrocoagulation. Bipolar instrumentation is preferred. Vessels must be isolated and then coagulated. If bipolar instruments
are not available, the vessel can be isolated with forceps and the electrode is then touched to the forceps. Care must be
taken not to cause excessive time destruction. Ligatures will be required on larger vessels (>2mm). Small sizes of suture
(4-0 to 10-0) can be used for these when they are in an accessible area. Vasculare clips (Hemoclips) are preferred when working
in a restricted area such as the body cavity or when speed is required. Occasionally hemorrhage will occur when none of the
above will be applicable. In these cases, the area can be packed off with absorbable foam sponges (Gel Foam). Due to the small
size of hedgehogs, magnification of the surgical field is advantageous. Optical loupes can be used for many procedures and
are reasonably priced. Operating microscopes will provide greater magnification and also lighting and are very beneficial
for many procedures. Working under magnification is very different from standard surgery. Every movement is magnified and
the field is very restricted. It is sometimes difficult to even find instruments. Surgical procedures performed under a microscope
can be done with much greater precision, but they also take more time. Considerable practice is required to master microsurgery.
The most commonly performed surgeries are tumor removal procedures and pyometra sugery.
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