Examination of head & neck
Examine the head and neck thoroughly, observing and recording any abnormalities:
External wounds: Check for swellings, bite wounds, snare injuries, etc over the head and along the neck.
General symmetry of the head and jaw: Check for fractures of skull and or jaws.
Nose: The nares and nasal cavities should be examined with a torch to assess for trauma, blood, discharge and ulcers, or evidence of inflammation (rhinitis). Check also for any foreign objects in the nose.
Ears: Check both inner and outer surfaces. Note any injuries, blood or foreign bodies. An otoscope can be used to examine the inside aspects of a tiger’s ears in detail. A normal ear should contain a fair amount of wax but the tympanic membrane (ear drum) should be clear and visible.
Lymph nodes: Palpate the retrophayngeal, and submandibular lymph nodes. Note if any nodes are enlarged or if there is a significant difference in size between those on the left and those on the right.
Eyes: Gently remove any dirt from the eyes with moist swabs. Check for injuries around the eyes and on the eyelids. It can be hard to examine the eyes of an anaesthetised tiger as they are often in a rolled down position and the third eyelid drawn across. However, the eyelids and conjunctiva should be assessed by everting the lid margins to expose the conjunctivae. Note any inflammation of the conjunctivae (conjunctivitis) or swelling, plus any discharges (mucopurulent, clear, haemorrhagic). The third eyelid (nictitating membrane) can be protruded and examined by pressing on the medial canthus of the eye through the upper eyelid. Check the eyeballs for injuries, foreign bodies, discharges, ulcers* or perforations of the cornea (the transparent part of the front of an eye), cataracts (cloudiness of the lens), haemorrhage within the eyeball, gross infection or collapse of the eyeball.
*Corneal ulceration can be revealed by a simple fluorescein test. A drop of fluorescein dye is placed onto the dorsal or ventral bulbar conjunctiva (a fluorescein test strip wetted with sterile water can also be used – in which case the wet strip is touched onto the bulbar conjunctiva). The eye should then be irrigated with sterile saline to flush excess fluorescein from the ocular surface. The eye is examined (preferably in a darkened space) using a blue UV light. Positive staining indicates a defect in the epithelium – i.e. an ulcer.
An ophthalmoscope is used to examine the internal structures of the eye in detail – the optic disc, retina and both chambers of the eye. For further details of the examination of the feline eye see Crispin 2007.
Oral cavity (mouth): Examine the oral cavity noting the condition of teeth, gingiva (gums), mucous membranes, tongue (all surfaces), larynx and back of throat. Note any physical trauma, ulcers, growths, inflammatory lesions, etc. Check for bones or sticks jammed between the upper teeth. Remove any dirt, food items, pieces of dart, etc. When the tiger is under sedation the mucous membranes should be pale pink.The colour of the mucous membranes is not only a useful vital sign during anaesthesia, but can also be diagnostically informative – see table below. A decreased CRT (capillary refill time) of less than 1 second may indicate pain, septic shock or fever.
| Abnormal mucous membrane colour | Common causes |
|---|---|
| Very pale pink or white | Anaemia, shock, dehydration, poor perfusion |
| Yellow | Liver disease, haemolysis |
| Bright pink or red | Bacterial endotoxaemia |
| Blue / purple | Circulatory / respiratory compromise |
All the tiger’s teeth should be examined, and a dental chart filled in. Any fractures, missing teeth, loose teeth, erupting teeth, abnormal discolourations, dental tartar/calculus accumulation or other abnormalities should be noted. Abnormalities of the gums should also be noted, eg: gingivitis (inflammation) or sinuses discharging to the gum.
Larynx: Palpate the larynx from the ventral aspect of the neck.
Trachea: Palpate the upper trachea from the ventral aspect of the neck and use a stethoscope to listen to the sound of air passing through the trachea as the tiger breathes in and out. Note any abnormal sounds such as fluid noises which may indicate excessive secretions or even inhaled saliva which may need removal.
