14.7 Haematologic, Immunologic, EENT & Dental Emergencies
Key Takeaways
- Anaemia reduces oxygen-carrying capacity without reducing oxygen saturation, so SpO2 can read normal in a profoundly anaemic patient.
- Sickle cell vaso-occlusive crisis requires oxygen, warmth, fluids, and aggressive analgesia; acute chest syndrome is the leading cause of death and splenic sequestration presents as sudden shock in children.
- A patient receiving chemotherapy who has a fever has febrile neutropenia until proven otherwise — a sepsis emergency even when they look well.
- In globe rupture, cover both eyes with a rigid shield without pressure and avoid anything raising intraocular pressure; in chemical splash, irrigate immediately and continuously.
- An avulsed permanent tooth is handled by the crown only, rinsed not scrubbed, reimplanted immediately where feasible, and otherwise stored in cold milk or saliva — never in water.
14.7 Haematologic, Immunologic, EENT & Dental Emergencies
CPCF Appendix A foundational knowledge #2 requires the PCP to understand haematologic (blood components, coagulation, fetal haematology), immunologic (typical immune responses), and ear-eye-nose-throat (EENT) systems — hearing, balance and the vestibular system, nasopharyngeal function, passage of air, food and liquid, and vision and pupillary response. Knowledge #4 requires the pathology of each. These are low-volume, high-consequence presentations that candidates routinely skip, and each carries a small but reliable share of Area H.
Haematologic Emergencies
Anaemia
Anaemia reduces oxygen-carrying capacity without necessarily reducing oxygen saturation — SpO2 can read 99% in a profoundly anaemic patient, because the haemoglobin present is fully saturated; there is simply not enough of it. Clinical features are fatigue, exertional dyspnoea, pallor (best assessed in the conjunctivae, palmar creases, and oral mucosa rather than skin colour), tachycardia, and in severe cases angina or heart failure. Causes to consider: chronic blood loss (gastrointestinal, menstrual), nutritional deficiency, chronic kidney disease, malignancy, and haemolysis.
Sickle Cell Disease
An inherited haemoglobinopathy in which deoxygenation causes red cells to deform into a rigid sickle shape that occludes microvasculature.
| Crisis type | Presentation | Field priority |
|---|---|---|
| Vaso-occlusive (pain) crisis | Severe bone, back, chest, or abdominal pain, often in a patient who knows exactly what is happening | Oxygen, warmth, fluids within scope, and aggressive analgesia |
| Acute chest syndrome | Chest pain, fever, hypoxia, new infiltrate; the leading cause of death | Oxygen, ventilatory support, urgent transport |
| Splenic sequestration | Rapid splenic pooling of blood, especially in children; sudden pallor, abdominal distension, shock | Treat as haemorrhagic shock; time-critical |
| Aplastic crisis | Profound anaemia after viral illness | Transport; transfusion is the treatment |
| Stroke | Focal neurological deficit, including in children | Stroke pathway |
[!IMPORTANT] Patients with sickle cell disease are among the most consistently under-treated for pain in the healthcare system, and racialized patients in particular have their pain reports discounted. A patient who states a familiar crisis is under way and requests a specific analgesic dose is providing expert history, not drug-seeking. Treating this pain adequately is both a clinical and an equity obligation under CPCF indicators F1.2 and F2.3.
Haemophilia and Other Coagulation Disorders
- Bleeding is disproportionate and delayed: a minor injury bleeds again hours later.
- Spontaneous joint (haemarthrosis) and muscle bleeds cause severe pain and swelling.
- Any head injury, however minor, is potentially catastrophic and warrants transport.
- Patients often carry their own factor concentrate and know their regimen. Bring it, and say so in handover.
- Avoid intramuscular injections and unnecessary venepuncture where alternatives exist.
Anticoagulated Patients
Warfarin, apixaban, rivaroxaban, dabigatran, clopidogrel, and ASA change the significance of every mechanism you assess. A ground-level fall in an anticoagulated older adult is a high-risk head injury (Section 13.5). Bleeding may be occult — retroperitoneal, intracranial, or gastrointestinal — and standard pressure may not control external bleeding.
Oncology and Immunosuppression
- Febrile neutropenia — a patient receiving chemotherapy with a fever is a sepsis emergency until proven otherwise, even if they look well and have no localizing signs. Time to antibiotics drives survival, so notify early.
- Indwelling central lines and ports may be the source of infection; do not access them without authorization.
- Immunosuppressed patients do not mount typical responses: no fever, no peritonism, no leucocytosis. Trust the trend and the story.
- Spinal cord compression from metastasis presents as back pain with new leg weakness, sensory change, or bladder or bowel dysfunction — an oncological emergency requiring urgent recognition.
Immunologic Emergencies
Section 14.1 covers anaphylaxis in depth. The additional examinable content here:
- Hypersensitivity is a spectrum. Isolated urticaria is not anaphylaxis; anaphylaxis requires involvement of airway, breathing, or circulation, or a rapidly progressing multisystem reaction. Epinephrine is for the latter.
- Biphasic reactions recur hours after apparent resolution, which is why patients who have received epinephrine require transport and observation even when they improve.
- Angioedema without urticaria or itching, particularly in a patient on an ACE inhibitor, is bradykinin-mediated. It responds poorly to epinephrine, antihistamines, and steroids, and the priority is airway vigilance and rapid transport — the airway can close over hours.
- Latex and food cross-reactivity (banana, avocado, kiwi, chestnut) matters when selecting gloves and equipment.
- Autoimmune conditions on immunosuppressive therapy carry the same infection risks as oncology patients, and long-term corticosteroid use raises the possibility of adrenal crisis during acute illness — hypotension unresponsive to fluids in a steroid-dependent patient should prompt that consideration and early notification.
Eye Emergencies
| Presentation | Key features | Management |
|---|---|---|
| Chemical splash | Pain, redness, blurring | Irrigate immediately and continuously, including during transport; remove contact lenses; alkalis are worse than acids; do not delay to identify the chemical |
| Penetrating injury / globe rupture | Irregular pupil, visible foreign body, extruded contents, sudden vision loss | Do not press, irrigate, or remove the object. Cover both eyes with a rigid shield, sit the patient up, avoid anything that raises intraocular pressure including vomiting and straining |
| Corneal abrasion / foreign body | Severe pain, tearing, foreign-body sensation, photophobia | Do not attempt removal of an embedded object; transport for examination |
| Acute angle-closure glaucoma | Severe unilateral eye pain, haloes, red eye, mid-dilated fixed pupil, nausea and vomiting | Time-critical vision loss; sit upright in dim light; urgent transport |
| Central retinal artery occlusion | Sudden painless monocular vision loss | A stroke of the eye; treat as a time-critical stroke-pathway presentation |
| Retinal detachment | Flashes, floaters, a curtain across the visual field | Urgent ophthalmology assessment |
Both eyes are covered for penetrating injury and globe rupture because conjugate movement of the uninjured eye drags the injured one. Warn the patient before covering both eyes and maintain verbal contact continuously — sudden sightlessness is frightening.
Ear, Nose and Throat Emergencies
Epistaxis is common and occasionally life-threatening.
- Anterior bleeds (Kiesselbach's plexus) are the majority and are usually controllable. Sit the patient upright and leaning forward, pinch the soft cartilaginous part of the nose continuously for 10 to 15 minutes without releasing to check, and apply cold to the bridge or neck. Leaning back sends blood into the pharynx, causing vomiting and aspiration.
- Posterior bleeds produce bleeding into the pharynx despite correct pressure, and are more common in older, hypertensive, or anticoagulated patients. These need transport and specialist packing, and can cause significant blood loss.
- Assess for hypovolaemia — swallowed blood conceals the true volume — and remember that haematemesis of swallowed blood is common.
Foreign bodies in the ear or nose are usually paediatric and rarely urgent, with two exceptions: button batteries, which cause liquefactive necrosis within hours and are a true emergency, and impacted objects causing airway compromise.
Vertigo — distinguish peripheral causes (benign paroxysmal positional vertigo, vestibular neuritis, Ménière's disease: usually positional, with hearing symptoms, fatigable nystagmus) from central causes (stroke, particularly posterior circulation: associated with headache, diplopia, dysarthria, ataxia, or other neurological findings, and non-fatigable nystagmus). Sudden vertigo with any additional neurological finding is a stroke until proven otherwise.
Ludwig's angina and deep neck infection — bilateral submandibular swelling, an elevated tongue, drooling, trismus, and a "hot potato" voice — is a rapidly progressive airway emergency. Keep the patient upright, do not attempt airway instrumentation that could precipitate obstruction, give oxygen, and transport urgently with early notification.
Post-tonsillectomy haemorrhage, usually 5 to 10 days after surgery, can be brisk and is an airway emergency in a child who is swallowing blood. Sit upright, suction, and transport urgently.
Dental Emergencies
- Avulsed permanent tooth — handle by the crown only, never the root. Rinse gently with saline or milk if visibly dirty, do not scrub. Reimplant into the socket immediately where feasible and where the patient is alert and cooperative; otherwise store in cold milk, the patient's own saliva, or a proprietary tooth-preservation solution. Never store in water, which destroys the periodontal ligament cells. Survival falls rapidly after 30 to 60 minutes.
- Avulsed primary (baby) teeth are not reimplanted — reimplantation can damage the developing permanent tooth.
- Dental haemorrhage after extraction: have the patient bite firmly on a rolled gauze pad over the socket for 15 to 20 minutes. Consider anticoagulation and bleeding disorders if it persists.
- Dental abscess — facial swelling with fever, trismus, and difficulty swallowing can progress to a deep neck space infection and airway compromise.
- Dentures should be left in place if intact and not obstructing, as they help maintain a mask seal, and removed if broken or displaced.
A 22-year-old with sickle cell disease reports severe bilateral leg and back pain identical to her previous vaso-occlusive crises. She is afebrile, SpO2 is 98% on room air, and she states she usually needs a specific opioid dose. What is the correct approach?
A 34-year-old is struck in the eye by a metal fragment. The pupil is irregular, there is a visible protrusion of dark tissue at the limbus, and vision in that eye is reduced. What is the correct prehospital management?
A 9-year-old has a permanent upper incisor avulsed during a fall at a playground. The tooth is found on the ground with visible dirt. The child is alert and cooperative. What is the correct management?