Veterinary nurses (VNs) are likely to find themselves in a situation where they are presented with an emergency case but there is no veterinary surgeon immediately available. It is therefore important that VNs should be able to deal with such cases and be able to recognise the clinical signs of life-threatening conditions. Veterinary nurses may often be the first point of contact and so should be able to triage the patient. The word 'triage' is derived from the French word meaning 'to sort'. Triage involves a logical examination of patients so that they can be classified according to the severity of their illness/injury. This ensures that the most critical patients/problems are dealt with first, and is therefore an important skill for any VN to master.

Primary Survey

A simple way to remember a logical order of immediate primary evaluation of the patient is 'ABC'--airway, breathing and circulation.

Airway

Does the patient have a patent airway? Obstructions can be caused by foreign bodies (e.g., ball), secretions (e.g., vomit, blood, saliva) and soft tissue swellings. Clear the airway if possible and intubate the trachea. A tracheostomy may have to be performed if the obstruction cannot be relieved.

Breathing

Is the animal breathing? If so, is it effective? Apnoeic patients should be intubated and ventilated with 100% oxygen. Patients that are breathing but show signs of respiratory insufficiency, e.g., orthopnoea, open-mouth breathing/gasping, cyanosis etc., require supplemental oxygen. Methods of providing supplemental oxygen include oxygen cages, facemasks and nasal catheters.

Circulation

Does the patient have a pulse? In the emergency or collapsed patient feel for a central pulse, e.g., femoral. If no pulse can be detected, auscultate the heart. If no heartbeat can be heard then perform cardiopulmonary cerebrovascular resuscitation (CPCR). A palpable femoral pulse indicates a systolic blood pressure of at least 60 mmHg. A palpable dorsal metatarsal pulse requires a blood pressure of at least 80 mmHg. Measure and record the rate and quality of the pulse. Weak, 'thready' pulses indicate decompensating shock or conditions such as pleural effusions or pneumothorax. Strong, 'bounding' pulses are seen with hyperdynamic shock. Auscultate the thorax whilst palpating a pulse--is there a pulse for every heartbeat? If a pulse deficit is detected then an electrocardiogram (ECG) should be performed.

Tachycardia (>160-180 bpm dogs, >200 bpm cats) can be caused by many factors including hypovolaemia, pain, sepsis and hyperthermia. Bradycardia (<60 bpm dogs, <80 bpm cats) is an unusual finding in the emergency patient. Causes include hypothermia, head trauma, hyperkalaemia and organophosphate toxicity.

Circulation is also evaluated by assessing the mucous membrane colour and the capillary refill time (CRT). Mucous membranes should be pink and moist. Pale mucous membranes can indicate anaemia, as well as shock or pain. Cyanosis manifests as blue mucous membranes, indicating poor oxygenation, usually associated with impaired respiration. Brick red or hyperaemic mucous membranes are seen in hyperdynamic shock and heatstroke.

Capillary refill time should be 1-2 seconds. A very rapid CRT (<1 second) is seen with hyper-dynamic shock. A slow CRT (>2 seconds) indicates poor perfusion. This can be caused for a variety of reasons including hypovolaemia, shock and pain.

Haemorrhage must be controlled where possible. External haemorrhage can be controlled by applying a pressure bandage to the area. Intra-abdominal haemorrhage should be controlled by placing a pressure bandage around the abdomen.

Additional Evaluation

Another vital sign which should be measured and recorded during the initial assessment is core body temperature. Patients should be treated for either hypothermia or hyperthermia using warming/cooling techniques to regain normal body temperature.

It is also useful to obtain an emergency laboratory database. This may vary depending on the facilities available, but should as a minimum include packed cell volume/total solids and serum electrolytes.

During the initial assessment of the patient it is important to get some background information from the client. Initial questions to ask may include:

 Why have they brought the patient in?

 How long has this been going on for?

 When was the patient last normal?

 In the event of an injury, did they see what happened?

The aim of the primary survey is to identify life-threatening respiratory and cardiovascular states. Once these have been addressed and the patient is stable then a more in-depth secondary survey can begin, which should include a full physical examination of the patient and further, in-depth investigations and treatments.