Sickle-cell disease is a blood disorder that is inherited in an autosomal recessive manner. It is characterized by the production of abnormal red blood cells that have a sickle shape. These abnormal cells are triggered by various factors such as low oxygen levels, dehydration, stress, and infection. The disease is caused by a specific mutation in the beta-globin chain of hemoglobin, resulting in the substitution of glutamic acid with valine at the sixth position. The gene responsible for this mutation is located on chromosome 11.

On the other hand, sickle-cell trait refers to the carrier state of the disease. Individuals with sickle-cell trait have one normal allele and one abnormal allele. Both alleles are co-dominant, meaning that both normal and abnormal hemoglobin are produced. As a result, individuals with sickle-cell trait do not experience the same severity of symptoms as those with sickle-cell disease.

When both parents are carriers of the sickle-cell trait, there is a 50% chance that their child will also be an unaffected carrier, a 25% chance that the child will be unaffected, and a 25% chance that the child will develop sickle-cell disease. This is because the inheritance of the disease follows the principles of autosomal recessive inheritance.

The sepsis 6 pathway is a time-sensitive protocol that should be started promptly and all 6 initial steps should be completed within 1 hour. It is important not to confuse the sepsis 6 pathway with the 6 hour care bundle. Time is of the essence when managing septic patients, and initiating the sepsis 6 pathway immediately has been proven to enhance survival rates in sepsis patients.

Further Reading:

There are multiple definitions of sepsis, leading to confusion among healthcare professionals. The Sepsis 3 definition describes sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection. The Sepsis 2 definition includes infection plus two or more SIRS criteria. The NICE definition states that sepsis is a clinical syndrome triggered by the presence of infection in the blood, activating the body’s immune and coagulation systems. The Sepsis Trust defines sepsis as a dysregulated host response to infection mediated by the immune system, resulting in organ dysfunction, shock, and potentially death.

The confusion surrounding sepsis terminology is further compounded by the different versions of sepsis definitions, known as Sepsis 1, Sepsis 2, and Sepsis 3. The UK organizations RCEM and NICE have not fully adopted the changes introduced in Sepsis 3, causing additional confusion. While Sepsis 3 introduces the use of SOFA scores and abandons SIRS criteria, NICE and the Sepsis Trust have rejected the use of SOFA scores and continue to rely on SIRS criteria. This discrepancy creates challenges for emergency department doctors in both exams and daily clinical practice.

To provide some clarity, RCEM now recommends referring to national standards organizations such as NICE, SIGN, BTS, or others relevant to the area. The Sepsis Trust, in collaboration with RCEM and NICE, has published a toolkit that serves as a definitive reference point for sepsis management based on the sepsis 3 update.

There is a consensus internationally that the terms SIRS and severe sepsis are outdated and should be abandoned. Instead, the terms sepsis and septic shock should be used. NICE defines septic shock as a life-threatening condition characterized by low blood pressure despite adequate fluid replacement and organ dysfunction or failure. Sepsis 3 defines septic shock as persisting hypotension requiring vasopressors to maintain a mean arterial pressure of 65 mmHg or more, along with a serum lactate level greater than 2 mmol/l despite adequate volume resuscitation.

NICE encourages clinicians to adopt an approach of considering sepsis in all patients, rather than relying solely on strict definitions. Early warning or flag systems can help identify patients with possible sepsis.

Pick’s disease is a rare neurodegenerative disorder that leads to a gradual decline in cognitive function known as frontotemporal dementia. One of the key features of this condition is the accumulation of tau proteins in neurons, forming silver-staining, spherical aggregations called Pick bodies.

Typically, Pick’s disease manifests between the ages of 40 and 60. Initially, individuals may experience changes in their personality, such as disinhibition, tactlessness, and vulgarity. They may also exhibit alterations in their moral values and attempt to distance themselves from their family. Concentration problems, over-activity, pacing, and wandering are also common symptoms during this stage.

What sets Pick’s disease apart from Alzheimer’s disease is that the personality changes occur before memory loss. As the disease progresses, patients will experience deficits in intellect, memory, and language.

On the other hand, Lewy body dementia (LBD) is characterized by the presence of Lewy bodies, which are different from the Pick bodies seen in Pick’s disease.

To diagnose diabetic ketoacidosis (DKA), all three of the following criteria must be present: ketonaemia (≥3 mmol/L) or ketonuria (> 2+ on urine dipstick), blood glucose > 11 mmol/L or known diabetes mellitus, and blood pH <7.3 or bicarbonate < 15 mmol/L. It is important to note that plasma osmolality and anion gap, although typically elevated in DKA, are not included in the diagnostic criteria. Further Reading: Diabetic ketoacidosis (DKA) is a serious complication of diabetes that occurs due to a lack of insulin in the body. It is most commonly seen in individuals with type 1 diabetes but can also occur in type 2 diabetes. DKA is characterized by hyperglycemia, acidosis, and ketonaemia. The pathophysiology of DKA involves insulin deficiency, which leads to increased glucose production and decreased glucose uptake by cells. This results in hyperglycemia and osmotic diuresis, leading to dehydration. Insulin deficiency also leads to increased lipolysis and the production of ketone bodies, which are acidic. The body attempts to buffer the pH change through metabolic and respiratory compensation, resulting in metabolic acidosis. DKA can be precipitated by factors such as infection, physiological stress, non-compliance with insulin therapy, acute medical conditions, and certain medications. The clinical features of DKA include polydipsia, polyuria, signs of dehydration, ketotic breath smell, tachypnea, confusion, headache, nausea, vomiting, lethargy, and abdominal pain. The diagnosis of DKA is based on the presence of ketonaemia or ketonuria, blood glucose levels above 11 mmol/L or known diabetes mellitus, and a blood pH below 7.3 or bicarbonate levels below 15 mmol/L. Initial investigations include blood gas analysis, urine dipstick for glucose and ketones, blood glucose measurement, and electrolyte levels. Management of DKA involves fluid replacement, electrolyte correction, insulin therapy, and treatment of any underlying cause. Fluid replacement is typically done with isotonic saline, and potassium may need to be added depending on the patient’s levels. Insulin therapy is initiated with an intravenous infusion, and the rate is adjusted based on blood glucose levels. Monitoring of blood glucose, ketones, bicarbonate, and electrolytes is essential, and the insulin infusion is discontinued once ketones are below 0.3 mmol/L, pH is above 7.3, and bicarbonate is above 18 mmol/L. Complications of DKA and its treatment include gastric stasis, thromboembolism, electrolyte disturbances, cerebral edema, hypoglycemia, acute respiratory distress syndrome, and acute kidney injury. Prompt medical intervention is crucial in managing DKA to prevent potentially fatal outcomes.

Digoxin is a medication used to treat atrial fibrillation and flutter as well as congestive cardiac failure. It belongs to a class of drugs called cardiac glycosides. Digoxin works by inhibiting the Na/K ATPase pump in the cardiac myocytes, which are the cells of the heart. This inhibition leads to an increase in the concentration of sodium inside the cells and indirectly increases the availability of calcium through the Na/Ca exchange mechanism. The rise in intracellular calcium levels results in a positive inotropic effect, meaning it strengthens the force of the heart’s contractions, and a negative chronotropic effect, meaning it slows down the heart rate.

However, it’s important to note that digoxin can cause toxicity, which is characterized by high levels of potassium in the blood, known as hyperkalemia. Normally, the Na/K ATPase pump helps maintain the balance of sodium and potassium by allowing sodium to leave the cells and potassium to enter. When digoxin blocks this pump, it disrupts this balance and leads to higher levels of potassium in the bloodstream.

Interestingly, the risk of developing digoxin toxicity is higher in individuals with low levels of potassium, known as hypokalemia. This is because digoxin binds to the ATPase pump at the same site as potassium. When potassium levels are low, digoxin can more easily bind to the ATPase pump and exert its inhibitory effects.

In summary, digoxin is a cardiac glycoside that is used to treat certain heart conditions. It works by inhibiting the Na/K ATPase pump, leading to increased intracellular calcium levels and resulting in a positive inotropic effect and negative chronotropic effect. However, digoxin can also cause toxicity, leading to high levels of potassium in the blood. The risk of toxicity is higher in individuals with low potassium levels.

Central retinal vein occlusion (CRVO) is a condition that usually leads to painless, one-sided vision loss. When examining the retina, it may appear similar to a ‘pizza thrown against a wall’, with swollen retinal veins, swelling of the optic disc, numerous flame-shaped hemorrhages, and cotton wool spots. Hypertension is present in about 65% of CRVO cases and is more common in individuals aged 65 and above.

On the other hand, branch retinal vein occlusion (BRVO) typically affects only one section of the retina, resulting in visual field deficits in that specific quadrant rather than complete vision loss.

Urinary alkalinisation, which involves the intravenous administration of sodium bicarbonate, carries the risk of hypokalaemia. It is important to note that both alkalosis and acidosis can cause shifts in potassium levels. In the case of alkalinisation, potassium is shifted from the plasma into the cells. Therefore, it is crucial to closely monitor the patient for hypokalaemia by checking their potassium levels every 1-2 hours.

Further Reading:

Salicylate poisoning, particularly from aspirin overdose, is a common cause of poisoning in the UK. One important concept to understand is that salicylate overdose leads to a combination of respiratory alkalosis and metabolic acidosis. Initially, the overdose stimulates the respiratory center, leading to hyperventilation and respiratory alkalosis. However, as the effects of salicylate on lactic acid production, breakdown into acidic metabolites, and acute renal injury occur, it can result in high anion gap metabolic acidosis.

The clinical features of salicylate poisoning include hyperventilation, tinnitus, lethargy, sweating, pyrexia (fever), nausea/vomiting, hyperglycemia and hypoglycemia, seizures, and coma.

When investigating salicylate poisoning, it is important to measure salicylate levels in the blood. The sample should be taken at least 2 hours after ingestion for symptomatic patients or 4 hours for asymptomatic patients. The measurement should be repeated every 2-3 hours until the levels start to decrease. Other investigations include arterial blood gas analysis, electrolyte levels (U&Es), complete blood count (FBC), coagulation studies (raised INR/PTR), urinary pH, and blood glucose levels.

To manage salicylate poisoning, an ABC approach should be followed to ensure a patent airway and adequate ventilation. Activated charcoal can be administered if the patient presents within 1 hour of ingestion. Oral or intravenous fluids should be given to optimize intravascular volume. Hypokalemia and hypoglycemia should be corrected. Urinary alkalinization with intravenous sodium bicarbonate can enhance the elimination of aspirin in the urine. In severe cases, hemodialysis may be necessary.

Urinary alkalinization involves targeting a urinary pH of 7.5-8.5 and checking it hourly. It is important to monitor for hypokalemia as alkalinization can cause potassium to shift from plasma into cells. Potassium levels should be checked every 1-2 hours.

In cases where the salicylate concentration is high (above 500 mg/L in adults or 350 mg/L in children), sodium bicarbonate can be administered intravenously. Hemodialysis is the treatment of choice for severe poisoning and may be indicated in cases of high salicylate levels, resistant metabolic acidosis, acute kidney injury, pulmonary edema, seizures and coma.

In the latest guideline published in 2021 by RCEM and NPIS regarding antidote availability for emergency departments, it is emphasized that immediate access to sodium bicarbonate is essential for treating TCA overdose. It is worth noting that previous versions of the guideline included glucagon as a recommended treatment for TCA overdose, but this reference has been omitted in the latest edition.

Further Reading:

Salicylate poisoning, particularly from aspirin overdose, is a common cause of poisoning in the UK. One important concept to understand is that salicylate overdose leads to a combination of respiratory alkalosis and metabolic acidosis. Initially, the overdose stimulates the respiratory center, leading to hyperventilation and respiratory alkalosis. However, as the effects of salicylate on lactic acid production, breakdown into acidic metabolites, and acute renal injury occur, it can result in high anion gap metabolic acidosis.

The clinical features of salicylate poisoning include hyperventilation, tinnitus, lethargy, sweating, pyrexia (fever), nausea/vomiting, hyperglycemia and hypoglycemia, seizures, and coma.

When investigating salicylate poisoning, it is important to measure salicylate levels in the blood. The sample should be taken at least 2 hours after ingestion for symptomatic patients or 4 hours for asymptomatic patients. The measurement should be repeated every 2-3 hours until the levels start to decrease. Other investigations include arterial blood gas analysis, electrolyte levels (U&Es), complete blood count (FBC), coagulation studies (raised INR/PTR), urinary pH, and blood glucose levels.

To manage salicylate poisoning, an ABC approach should be followed to ensure a patent airway and adequate ventilation. Activated charcoal can be administered if the patient presents within 1 hour of ingestion. Oral or intravenous fluids should be given to optimize intravascular volume. Hypokalemia and hypoglycemia should be corrected. Urinary alkalinization with intravenous sodium bicarbonate can enhance the elimination of aspirin in the urine. In severe cases, hemodialysis may be necessary.

Urinary alkalinization involves targeting a urinary pH of 7.5-8.5 and checking it hourly. It is important to monitor for hypokalemia as alkalinization can cause potassium to shift from plasma into cells. Potassium levels should be checked every 1-2 hours.

In cases where the salicylate concentration is high (above 500 mg/L in adults or 350 mg/L in children), sodium bicarbonate can be administered intravenously. Hemodialysis is the treatment of choice for severe poisoning and may be indicated in cases of high salicylate levels, resistant metabolic acidosis, acute kidney injury, pulmonary edema, seizures and coma.

The standard facial X-ray series consists of two occipitomental x-rays: the Occipitomental (or Occipitomental 15º) and the Occipitomental 30º. The Occipitomental view captures the upper and middle thirds of the face, showing important structures such as the orbital margins, frontal sinuses, zygomatic arches, and maxillary antra. On the other hand, the Occipitomental 30º view uses a 30º caudal angulation, resulting in a less clear visualization of the orbits but a clearer view of the zygomatic arches and the walls of the maxillary antra.

Further Reading:

Zygomatic injuries, also known as zygomatic complex fractures, involve fractures of the zygoma bone and often affect surrounding bones such as the maxilla and temporal bones. These fractures can be classified into four positions: the lateral and inferior orbital rim, the zygomaticomaxillary buttress, and the zygomatic arch. The full extent of these injuries may not be visible on plain X-rays and may require a CT scan for accurate diagnosis.

Zygomatic fractures can pose risks to various structures in the face. The temporalis muscle and coronoid process of the mandible may become trapped in depressed fractures of the zygomatic arch. The infraorbital nerve, which passes through the infraorbital foramen, can be injured in zygomaticomaxillary complex fractures. In orbital floor fractures, the inferior rectus muscle may herniate into the maxillary sinus.

Clinical assessment of zygomatic injuries involves observing facial asymmetry, depressed facial bones, contusion, and signs of eye injury. Visual acuity must be assessed, and any persistent bleeding from the nose or mouth should be noted. Nasal injuries, including septal hematoma, and intra-oral abnormalities should also be evaluated. Tenderness of facial bones and the temporomandibular joint should be assessed, along with any step deformities or crepitus. Eye and jaw movements must also be evaluated.

Imaging for zygomatic injuries typically includes facial X-rays, such as occipitomental views, and CT scans for a more detailed assessment. It is important to consider the possibility of intracranial hemorrhage and cervical spine injury in patients with facial fractures.

Management of most zygomatic fractures can be done on an outpatient basis with maxillofacial follow-up, assuming the patient is stable and there is no evidence of eye injury. However, orbital floor fractures should be referred immediately to ophthalmologists or maxillofacial surgeons. Zygomatic arch injuries that restrict mouth opening or closing due to entrapment of the temporalis muscle or mandibular condyle also require urgent referral. Nasal fractures, often seen in conjunction with other facial fractures, can be managed by outpatient ENT follow-up but should be referred urgently if there is uncontrolled epistaxis, CSF rhinorrhea, or septal hematoma.

The CIWA scale, also known as the Clinical Institute Withdrawal Assessment for Alcohol scale, is a scale consisting of ten items that is utilized in the evaluation and management of alcohol withdrawal. It is currently recommended by both NICE and the Royal College of Emergency Medicine for assessing patients experiencing acute alcohol withdrawal. The maximum score on the CIWA scale is 67, with scores indicating the severity of withdrawal symptoms. A score of less than 5 suggests mild withdrawal, while a score between 6 and 20 indicates moderate withdrawal. Any score above 20 is considered severe withdrawal. The ten items evaluated on the scale encompass common symptoms and signs of alcohol withdrawal, such as nausea/vomiting, tremors, sweating, anxiety, agitation, sensory disturbances, and cognitive impairments.

In addition to the CIWA scale, there are other screening tools available for assessing various conditions. The CAGE questionnaire is commonly used to screen for alcohol-related issues. The STEPI is utilized as a screening tool for early symptoms of the schizophrenia prodrome. The EPDS is an evidence-based questionnaire that can be employed to screen for postnatal depression. Lastly, the SCOFF questionnaire is a screening tool used to identify the possible presence of eating disorders.

For further information on the assessment and management of acute alcohol withdrawal, the NICE pathway is a valuable resource. The RCEM syllabus also provides relevant information on this topic. Additionally, the MHC1 module on alcohol and substance misuse offers further reading material for those interested in this subject.