The majority of treatments provided to individuals with sickle cell disease are supportive measures that have limited impact on the underlying pathophysiology of the condition.

Currently, the only approved therapy that can modify the disease is Hydroxyurea. This medication is believed to function by increasing the levels of fetal hemoglobin, which in turn decreases the concentration of HbS within the cells and reduces the abnormal hemoglobin tendency to form polymers.

Hydroxyurea is currently authorized for use in adult patients who experience recurrent moderate-to-severe painful crises (at least three in the past 12 months). Its approval is specifically for reducing the frequency of these painful episodes and the need for blood transfusions.

Anaemia can be categorized based on the size of red blood cells. Microcytic anaemia, characterized by a mean corpuscular volume (MCV) of less than 80 fl, can be caused by various factors such as iron deficiency, thalassaemia, anaemia of chronic disease (which can also be normocytic), sideroblastic anaemia (which can also be normocytic), lead poisoning, and aluminium toxicity (although this is now rare and mainly affects haemodialysis patients).

On the other hand, normocytic anaemia, with an MCV ranging from 80 to 100 fl, can be attributed to conditions like haemolysis, acute haemorrhage, bone marrow failure, anaemia of chronic disease (which can also be microcytic), mixed iron and folate deficiency, pregnancy, chronic renal failure, and sickle-cell disease.

Lastly, macrocytic anaemia, characterized by an MCV greater than 100 fl, can be caused by factors such as B12 deficiency, folate deficiency, hypothyroidism, reticulocytosis, liver disease, alcohol abuse, myeloproliferative disease, myelodysplastic disease, and certain drugs like methotrexate, hydroxyurea, and azathioprine.

It is important to understand the different causes of anaemia based on red cell size as this knowledge can aid in the diagnosis and management of this condition.

Plasmodium falciparum malaria is transmitted by female mosquitoes of the Anopheles genus. The Aedes genus, on the other hand, is responsible for spreading diseases like dengue fever and yellow fever. The parasite enters hepatocytes and undergoes asexual reproduction, resulting in the release of merozoites into the bloodstream. These merozoites then invade the red blood cells of the host. The incubation period for Plasmodium falciparum malaria ranges from 7 to 14 days.

The main symptom of malaria is known as the malarial paroxysm, which consists of a cyclical pattern of cold chills, followed by a stage of intense heat, and finally a period of profuse sweating as the fever subsides. However, some individuals may experience a continuous fever instead.

Currently, the recommended treatment for P. falciparum malaria is artemisinin-based combination therapy (ACT). This involves combining fast-acting artemisinin-based compounds with drugs from a different class. Companion drugs used in ACT include lumefantrine, mefloquine, amodiaquine, sulfadoxine/pyrimethamine, piperaquine, and chlorproguanil/dapsone. Artemisinin derivatives such as dihydroartemisinin, artesunate, and artemether are also used.

If artemisinin combination therapy is not available, oral quinine or atovaquone with proguanil hydrochloride can be used as an alternative. However, quinine is not well-tolerated for prolonged treatment and should be combined with another drug, typically oral doxycycline (or clindamycin for pregnant women and young children).

Severe or complicated cases of falciparum malaria require specialized care in a high dependency unit or intensive care setting. Intravenous artesunate is recommended for all patients with severe or complicated falciparum malaria, as well as those at high risk of developing severe disease (e.g., if more than 2% of red blood cells are parasitized) or if the patient is unable to take oral treatment. After a minimum of 24 hours of intravenous artesunate treatment and improvement in the patient’s condition, a full course of artemisinin combination therapy should be administered orally.

The earliest and most common clinical indication of malignant hyperthermia is typically an increase in end tidal CO2 levels.

Further Reading:

Malignant hyperthermia is a rare and life-threatening syndrome that can be triggered by certain medications in individuals who are genetically susceptible. The most common triggers are suxamethonium and inhalational anaesthetic agents. The syndrome is caused by the release of stored calcium ions from skeletal muscle cells, leading to uncontrolled muscle contraction and excessive heat production. This results in symptoms such as high fever, sweating, flushed skin, rapid heartbeat, and muscle rigidity. It can also lead to complications such as acute kidney injury, rhabdomyolysis, and metabolic acidosis. Treatment involves discontinuing the trigger medication, administering dantrolene to inhibit calcium release and promote muscle relaxation, and managing any associated complications such as hyperkalemia and acidosis. Referral to a malignant hyperthermia center for further investigation is also recommended.

A recent audit conducted by the Royal College of Emergency Medicine (RCEM) in 2018 revealed a concerning decline in the standards of pain management for children with fractured limbs in Emergency Departments (EDs). The audit found that the majority of patients experienced longer waiting times for pain relief compared to previous years. Shockingly, more than 1 in 10 children who presented with significant pain due to a limb fracture did not receive any pain relief at all.

To address this issue, the Agency for Health Care Policy and Research (AHCPR) in the USA recommends following the ABCs of pain management for all patients, including children. This approach involves regularly asking about pain, systematically assessing it, believing the patient and their family in their reports of pain and what relieves it, choosing appropriate pain control options, delivering interventions in a timely and coordinated manner, and empowering patients and their families to have control over their pain management.

The RCEM has established standards that require a child’s pain to be assessed within 15 minutes of their arrival at the ED. This is considered a fundamental standard. Various rating scales are available for assessing pain in children, with the choice depending on the child’s age and ability to use the scale. These scales include the Wong-Baker Faces Pain Rating Scale, Numeric rating scale, and Behavioural scale.

To ensure timely administration of analgesia to children in acute pain, the RCEM has set specific standards. These standards state that 100% of patients in severe pain should receive appropriate analgesia within 60 minutes of their arrival or triage, whichever comes first. Additionally, 75% should receive analgesia within 30 minutes, and 50% within 20 minutes.

Fluoxetine is the preferred antidepressant for children and young individuals, as it is the only medication approved for this purpose. Limited research exists regarding the effectiveness of other antidepressants in this specific age group.

Cardiac tamponade is characterized by several classical signs, including distended neck veins, muffled heart sounds, and hypotension. When neck veins are distended, it suggests that the right ventricle is not filling properly. In cases of trauma, this is often caused by the compression of air (tension pneumothorax) or fluid (blood in the pericardial space). One important distinguishing feature is the deviation of the trachea.

Further Reading:

Cardiac tamponade, also known as pericardial tamponade, occurs when fluid accumulates in the pericardial sac and compresses the heart, leading to compromised blood flow. Classic clinical signs of cardiac tamponade include distended neck veins, hypotension, muffled heart sounds, and pulseless electrical activity (PEA). Diagnosis is typically done through a FAST scan or an echocardiogram.

Management of cardiac tamponade involves assessing for other injuries, administering IV fluids to reduce preload, performing pericardiocentesis (inserting a needle into the pericardial cavity to drain fluid), and potentially performing a thoracotomy. It is important to note that untreated expanding cardiac tamponade can progress to PEA cardiac arrest.

Pericardiocentesis can be done using the subxiphoid approach or by inserting a needle between the 5th and 6th intercostal spaces at the left sternal border. Echo guidance is the gold standard for pericardiocentesis, but it may not be available in a resuscitation situation. Complications of pericardiocentesis include ST elevation or ventricular ectopics, myocardial perforation, bleeding, pneumothorax, arrhythmia, acute pulmonary edema, and acute ventricular dilatation.

It is important to note that pericardiocentesis is typically used as a temporary measure until a thoracotomy can be performed. Recent articles published on the RCEM learning platform suggest that pericardiocentesis has a low success rate and may delay thoracotomy, so it is advised against unless there are no other options available.

Acute adrenal insufficiency, also known as Addisonian crisis, is a rare condition that can have catastrophic consequences if not diagnosed in a timely manner. It is more prevalent in women and typically occurs between the ages of 30 and 50.

Addison’s disease is caused by a deficiency in the production of steroid hormones by the adrenal glands, affecting glucocorticoid, mineralocorticoid, and sex steroid production. The main causes of Addison’s disease include autoimmune adrenalitis, bilateral adrenalectomy, Waterhouse-Friderichsen syndrome, tuberculosis, and congenital adrenal hyperplasia.

An Addisonian crisis can be triggered by the intentional or accidental withdrawal of steroid therapy, as well as factors such as infection, trauma, myocardial infarction, cerebral infarction, asthma, hypothermia, and alcohol abuse.

The clinical features of Addison’s disease include weakness, lethargy, hypotension (especially orthostatic hypotension), nausea, vomiting, weight loss, reduced axillary and pubic hair, depression, and hyperpigmentation in areas such as palmar creases, buccal mucosa, and exposed skin.

During an Addisonian crisis, the main symptoms are usually hypoglycemia and shock, characterized by tachycardia, peripheral vasoconstriction, hypotension, altered consciousness, and even coma.

Biochemical features that can confirm the diagnosis of Addison’s disease include increased ACTH levels, hyponatremia, hyperkalemia, hypercalcemia, hypoglycemia, and metabolic acidosis. Diagnostic investigations may involve the Synacthen test, plasma ACTH level measurement, plasma renin level measurement, and adrenocortical antibody testing.

Management of Addison’s disease should be overseen by an Endocrinologist. Treatment typically involves the administration of hydrocortisone, fludrocortisone, and dehydroepiandrosterone. Some patients may also require thyroxine if there is hypothalamic-pituitary disease present. Treatment is lifelong, and patients should carry a steroid card and MedicAlert bracelet to alert healthcare professionals of their condition and the potential for an Addisonian crisis.

The superior orbital fissure is a gap in the back wall of the orbit, created by the space between the greater and lesser wings of the sphenoid bone. Several structures pass through it to enter the orbit, starting from the top and going downwards. These include the lacrimal nerve (a branch of CN V1), the frontal nerve (another branch of CN V1), the superior ophthalmic vein, the trochlear nerve (CN IV), the superior division of the oculomotor nerve (CN III), the nasociliary nerve (a branch of CN V1), the inferior division of the oculomotor nerve (CN III), the abducens nerve (CN VI), and the inferior ophthalmic vein.

Adjacent to the superior orbital fissure, on the back wall of the orbit and towards the middle, is the optic canal. The optic nerve (CN II) exits the orbit through this canal, along with the ophthalmic artery.

Superior orbital fissure syndrome (SOFS) is a condition characterized by a combination of symptoms and signs that occur when cranial nerves III, IV, V1, and VI are compressed or injured as they pass through the superior orbital fissure. This condition also leads to swelling and protrusion of the eye due to impaired drainage and congestion. The main causes of SOFS are trauma, tumors, and inflammation. It is important to note that CN II is not affected by this syndrome, as it follows a separate path through the optic canal.

The ability to rotate the neck actively by 45 degrees to the left and right is a crucial distinction between the ‘no risk’ and ‘low risk’ categories when applying the Canadian C-spine rules. In this case, the patient does not exhibit any high-risk factors for cervical spine injury according to the Canadian C-spine rule. However, they do have a low-risk factor due to their involvement in a minor rear-end motor collision. If a patient with a low-risk factor is unable to actively rotate their neck by 45 degrees in either direction, they should undergo imaging. It is important to note that while the patient’s use of anticoagulation medication may affect the need for brain imaging, it typically does not impact the decision to perform a CT scan of the cervical spine.

Further Reading:

When assessing for cervical spine injury, it is recommended to use the Canadian C-spine rules. These rules help determine the risk level for a potential injury. High-risk factors include being over the age of 65, experiencing a dangerous mechanism of injury (such as a fall from a height or a high-speed motor vehicle collision), or having paraesthesia in the upper or lower limbs. Low-risk factors include being involved in a minor rear-end motor vehicle collision, being comfortable in a sitting position, being ambulatory since the injury, having no midline cervical spine tenderness, or experiencing a delayed onset of neck pain. If a person is unable to actively rotate their neck 45 degrees to the left and right, their risk level is considered low. If they have one of the low-risk factors and can actively rotate their neck, their risk level remains low.

If a high-risk factor is identified or if a low-risk factor is identified and the person is unable to actively rotate their neck, full in-line spinal immobilization should be maintained and imaging should be requested. Additionally, if a patient has risk factors for thoracic or lumbar spine injury, imaging should be requested. However, if a patient has low-risk factors for cervical spine injury, is pain-free, and can actively rotate their neck, full in-line spinal immobilization and imaging are not necessary.

NICE recommends CT as the primary imaging modality for cervical spine injury in adults aged 16 and older, while MRI is recommended as the primary imaging modality for children under 16.

Different mechanisms of spinal trauma can cause injury to the spine in predictable ways. The majority of cervical spine injuries are caused by flexion combined with rotation. Hyperflexion can result in compression of the anterior aspects of the vertebral bodies, stretching and tearing of the posterior ligament complex, chance fractures (also known as seatbelt fractures), flexion teardrop fractures, and odontoid peg fractures. Flexion and rotation can lead to disruption of the posterior ligament complex and posterior column, fractures of facet joints, lamina, transverse processes, and vertebral bodies, and avulsion of spinous processes. Hyperextension can cause injury to the anterior column, anterior fractures of the vertebral body, and potential retropulsion of bony fragments or discs into the spinal canal. Rotation can result in injury to the posterior ligament complex and facet joint dislocation.