12 minute read
Don't get caught out!
Discover what to do if a patient has a medical emergency in your chair
CPD: 0.5 hours Scientific
Medical emergencies can happen at literally any time. You can't predict them, but you can be prepared to manage them. The five medical situations that follow are some of the more likely that you may face in a dental practice.
We have detailed their clinical presentations and management principles. This is not designed to replace existing protocols and/or guidelines but to elaborate on the detection, assessment and management of these emergencies from a paramedic’s perspective (the author having attended many of these in dental settings).
Syncope
Syncope is defined as a sudden loss of consciousness, lasting seconds to minutes and normally with complete recovery 1. Syncope can be broadly classified into three groups: cardiac, reflex and orthostatic. Cardiac syncope results from abnormally slow, fast or irregular cardiac rhythms, along with pre-existing structural changes to the heart (e.g. cardiomyopathies, valvular heart disease).
Orthostatic syncope results from the inability of the sympathetic nervous system to maintain adequate blood pressure during positional changes. For example, when a person goes from lying down to standing up, greater pressure is required to pump blood against gravity, so the heart rate and force of contraction increase cardiac output and peripheral arteries and arterioles constrict to reduce vessel diameter, thereby increasing pressure. In some individuals, this normal compensatory mechanism becomes inefficient, influenced by age, medications (e.g. beta-blockers) or blood volume depletion (e.g. dehydration)1.
Lastly, and possibly the most likely to be seen in dental practice, is the reflex syncope. These result from inappropriate reflex activity, with dilation of blood vessels and/or a reduction in heart rate in response to specific stimuli, often mediated by the vagus nerve (vasovagal syncope). Common triggers include pain, anxiety, intense emotions such as fear or exposure to trauma.
Just prior to loss of consciousness (sometimes referred to as pre-syncope), the individual will present with pale or ashen-coloured skin, profuse sweating, nausea, light-headedness, feelings of heat or chills and may experience visual disturbances (blurred vision or “seeing stars”).1 These symptoms are indicative of the sudden loss of blood flow to the brain and the body’s activation of the sympathetic nervous system in an attempt to compensate. Syncope of all types may be more likely if a person has reduced blood volume (from blood loss or dehydration) or already has their peripheral blood vessels dilated due to a hot environment.
Effective management of both syncope and pre-syncope involves positioning the person lying down with elevation of the legs where possible1. If the person is unconscious, positioning laterally in the recovery position may be necessary to maintain a clear airway, especially if vomiting occurs secondary to nausea. Vital signs should be recorded where possible including pulse rate, rhythm and strength and respiratory rate. Where equipment is available blood pressure, pulse oximetry and electrocardiography (ECG) should also be recorded. In the absence of equipment, the pulse rate, regularity and strength can be useful in terms of detecting abnormally fast, slow or irregular heart rhythms. Most people will recover spontaneously1. However, due to the large range of possible contributors to syncope, medical attention should be sought to establish a cause, especially if the patient demonstrates signs of cardiac syncope. Failure of the person to improve with positioning should prompt immediate medical care via ambulance response.
Anaphylaxis
Anaphylaxis is a life-threatening multisystem allergic reaction that can result from exposure to a number of antigenic substances. Common antigens include foods (nuts, shellfish), insect bites and medications (e.g., penicillin). In healthcare settings, apart from medications, common antigens include iodine, chlorhexidine, latex and adhesive (e.g., tape). It is vital to check for known allergies to avoid inadvertent exposure, but as reactions often escalate with subsequent exposures, the first presentation of anaphylaxis may be to a substance that was not previously known to cause a reaction.
Clients suffering from anaphylaxis will commonly present with:
Cutaneous signs – redness/erythema of the skin, swelling and/or urticaria (“hives”)
Respiratory symptoms – shortness of breath, bronchospasm, and wheeze
Upper airway symptoms – difficulty talking or swallowing due to laryngeal oedema, swelling of the lips and/or tongue, and stridor (high-pitched upper airway noise)
Cardiovascular symptoms – tachycardia, hypotension, lightheadedness, dizziness, syncope/fainting
Cutaneous signs tend to be the most recognisable symptoms of anaphylaxis; however, anaphylaxis can also present in the absence of these signs. Sudden onset of hypotension, shortness of breath or upper airway swelling should be suspected to be anaphylaxis and treated as such.
Treatment should start with positioning Unless the client needs to be sitting up to relieve respiratory symptoms, they should be positioned supine, as there is a significant risk of collapse due to reduced blood pressure. A client with an altered conscious state should be positioned laterally in the recovery position to maintain their airway. Oxygen should be administered if available and titrated to pulse oximetry levels of 94-98% if pulse oximetry is available (otherwise oxygen at a flow rate of 1215 litres per minute).
Anxiety is best managed with information, psychological support and strategies to regulate the sympathetic nervous system
Intramuscular adrenaline (epinephrine) should be administered as soon as possible. This will often be available in the form of an autoinjector such as EpiPen® and Anapen®. These devices are preloaded with an adrenaline dose appropriate for an adult (300-500 micrograms) or child (150 micrograms)2. Pharmacologically, adrenaline targets the symptoms of anaphylaxis, increasing cardiac output and constricting the peripheral circulation to increase blood pressure and reduce capillary leakage responsible for tissue swelling. Adrenaline also dilates the bronchioles in the lungs, reversing bronchospasm1. Intramuscular adrenaline doses can be repeated every five minutes, and often more than one dose is required.
Clients with anaphylaxis may also require intravenous corticosteroids, intravenous fluids to treat hypotension, and/or inhaled bronchodilators (e.g., salbutamol, ipratropium bromide) for persistent bronchospasm. Severe cases may also require ongoing intravenous adrenaline infusions. For these reasons, early activation of an ambulance response will enable these additional treatments and rapid transport to a hospital for definitive care.
Anxiety
Apart from being a potential trigger for syncope, anxiety can present difficulties when managing a client in many healthcare settings. Clients presenting with anxiety may be having an acute emotional response, or the anxiety may be part of a diagnosed or undiagnosed mental health condition. In either situation, the anxious client may present with increased awareness of pain and hyperventilation. Signs of anxiety most easily recognised include increased respiratory rate, increased muscle tone (e.g. white knuckles of the hands on the armrest of the chair), a rigid posture/lack of movement and a slow blink rate. A person with anxiety may actively engage in deep breathing as a means of regulating their anxiety.
Anxiety is best managed with information, psychological support and strategies to regulate the sympathetic nervous system. As fear is often a precursor to anxiety, a well-informed client is less likely to feel out of control and anxious. Likewise, conversation can be both calming and distracting, as is music or other audio-visual media (audiovisual distraction can be particularly effective with children). Deep and slow breathing can be used effectively to reduce anxiety. For example, box breathing (breathing in slowly, holding the breath in, breathing out slowly, and holding the breath out before inhaling again) can reduce a person’s heart rate and have a calming effect. Mindfulness techniques such as grounding offer simple interventions that may be effective in calming a client. For example, some grounding techniques work by asking the person to describe five things they see, four things they feel, three things they hear, two things they smell and one thing they taste (5-4-3-2-1 grounding technique)4. This may or may not be appropriate at the moment, especially if some of those “things” are triggers for the person’s anxiety. Another technique is to give the person a cold pack to hold – and ask them to focus on the shape, temperature, and feel of it.
Choking / inhalation of foreign bodies
Upper airway obstruction is another potential emergency that may be encountered in dental practice, with fillings, dental burrs or crowns being the possible culprits. These objects, dependent on size, may either obstruct the upper airway or be aspirated into the lungs. In adults, the right main bronchus is larger and more vertical than the left. As a result, inhaled objects that are small enough to pass the vocal cords will most likely end up in the right bronchial tree, preserving left lung function.1
If back blows are not effective [for choking], chest thrusts can be attempted – these are similar to CPR compressions, but performed in a sharp, abrupt manner
Upper airway obstruction will present with sudden difficulty in breathing. If the obstruction is complete, the person will demonstrate significant effort of breathing, but without air movement or appreciable noise of breathing. If the upper airway is partially blocked, breathing is normally noisy, often with high-pitched breathing sounds (stridor) and an urge to cough. In either case, the person will also present with signs of severe respiratory distress, such as increased effort of breathing, pale and/or cyanosed (blue) skin, elevated breathing rate and heart rate, and decreasing oxygen levels (if able to be measured).
The best immediate management is per established first aid guidelines.5 For a partial obstruction, the person should be encouraged to cough to remove the object. If the object is not able to be coughed up, urgent medical attention should be sought via ambulance. The person should be kept calm, and oxygen administered if available (titrated to SpO2 of 94-98%).3 For a complete obstruction with an ineffective cough, back blows should be used, ideally with the person positioned to allow gravity to assist with the removal of the object (i.e., bent forward, or for a child, facing head down). If back blows are not effective, chest thrusts can be attempted – these are similar to CPR compressions, but performed in a sharp, abrupt manner.5 If at any point the obstruction is visible in the oral cavity, it can be removed manually or with the assistance of suction.
If back blow and chest thrusts are not effective, and in facilities where personnel are trained in the procedure, direct laryngoscopy can be performed, and the obstruction removed with Magill’s forceps +/- suction.1 As laryngoscopy can be performed by most paramedics, early activation of an ambulance response is important should the earlier first aid measure be ineffective.
Hypoglycaemia
Hypoglycaemia (low blood glucose) occurs when there is reduced intake of carbohydrates, increased metabolic use of glucose and/or increased action of insulin. Under normal conditions, insulin is released from the pancreas in response to rising blood glucose after meals, facilitating the uptake of glucose into all body tissues with the exception of the central nervous system.1 In the diabetic patient, insulin is either underproduced (type 1 diabetes) or the body develops resistance to insulin, making it less effective (type 2 diabetes).
Hypoglycaemic events are generally less common in non-diabetic patients as they have mechanisms to preserve their blood glucose levels. When blood glucose drops, the body responds by releasing glucagon from the pancreas. Glucagon stimulates the breakdown of glycogen into glucose within the liver, increasing glucose within the blood.1 Glycogen stores tend to be lacking in individuals who have liver disease or in people who have been fasting. Clients avoiding food intake prior to dental appointments may make them prone to hypoglycaemic events.
Hypoglycaemia presents with signs of sympathetic nervous system activation: tachycardia, dilated pupils and pale, cool, clammy skin.1,6 Due to the lack of glucose supply to the central nervous system, patients can present with a range of neurological symptoms including confusion, agitation, an altered level of consciousness, slurred speech, unsteady gait, seizure activity and/or complete loss of consciousness.1,6
“Treatment of hypoglycaemia is dependent on the individual’s conscious state; more specifically, their ability to ingest glucose”
Treatment of hypoglycaemia is dependent on the individual’s conscious state; more specifically, their ability to ingest glucose orally without risking airway compromise. If the person is able to safely ingest fluids, treatment should include offering the person drinks such as juice or soft drink with a high simple sugar content.1,6 Honey or glucose gel can also be used, as can lollies or other foods, but fluids or gels are often easier to consume for confused clients. Where an individual is not able to safely ingest glucose, treatment involves injection of intramuscular glucagon or an intravenous infusion of glucose where available.1 Occasionally, individuals with diabetes will carry glucagon injection kits, but otherwise treatment with glucagon or intravenous glucose will require the attendance of paramedics outside of a hospital or medical clinic. As the person’s conscious state can deteriorate, early recognition is important to be able to treat the condition with oral glucose as opposed to invasive treatments that may not be readily available. A drop in the person’s conscious state will also necessitate repositioning to maintain a clear airway, notwithstanding the need to manage aggressive behaviour and/or seizure activity.
About the author: Dennis Walker is a lecturer and clinical placement coordinator for the undergraduate Paramedicine program at the University of Southern Queensland. He is also a registered paramedic, having worked within the Queensland Ambulance Service for 27 years in a range of roles including Critical Care Paramedic, Flight Paramedic, Isolated Practice Area Paramedic and Clinical Support Officer. Dennis is in the final months of completing his PhD in the area of prehospital medication safety.
References
1. Hockberger, R., Gausche-Hill, M., Wilcox, S. R., Walls, R., & Erickson, T. B. Rosen’s Emergency Medicine: Concepts and Clinical Practice (10th Ed). Elsevier; 2022.
2. Australian Society of Clinical Immunology and Allergy. Acute Management of Anaphylaxis. 2023. Accessed via https://www.allergy.org. au/images/ASCIA_HP_Guidelines_Acute_ Management_Anaphylaxis_2023.pdf
3. ANZCOR Guideline 9.2.10 – The Use of Oxygen in Emergencies. ANZCOR; accessed via https:// www.anzcor.org/home/new-guidelinepage-2/guideline-9-2-10-the-use-of-oxygenin-emergencies
4. Schuldt, W. Grounding Techniques. Therapist Aid; accessed via https://www.therapistaid. com/therapy-article/grounding-techniquesarticle
5. ANZCOR Basic Life Support Guideline 4 –Airway. ANZCOR; accessed via https://www. anzcor.org/home/basic-life-support/guideline4-airway
6. ANZCOR Guideline 9.2.9 – First Aid Management of a Diabetic Emergency. ANZCOR; accessed via https://www.anzcor.org/home/new-guidelinepage-2/guideline-9-2-9-first-aid-managementof-a-diabetic-emergency
