Patients who experience a seizure(s) should be informed about their ability to drive. There are two important instructions to follow in this regard. Firstly, they must refrain from driving for a period of 6 months. Secondly, they must notify the appropriate authority, such as the DVLA or DVA in Northern Ireland. In the case of a single seizure, driving should be suspended for 6 months from the date of the seizure. However, if an underlying cause that increases the risk of seizures is identified, driving should be halted for 12 months. In the case of multiple seizures or epilepsy, driving should be ceased for 12 months from the most recent seizure.

Further Reading:

Blackouts are a common occurrence in the emergency department and can have serious consequences if they happen while a person is driving. It is crucial for doctors in the ED to be familiar with the guidelines set by the DVLA (Driver and Vehicle Licensing Agency) regarding driving restrictions for patients who have experienced a blackout.

The DVLA has specific rules for different types of conditions that may cause syncope (loss of consciousness). For group 1 license holders (car/motorcycle use), if a person has had a first unprovoked isolated seizure, they must refrain from driving for 6 months or 12 months if there is an underlying causative factor that may increase the risk. They must also notify the DVLA. For group 2 license holders (bus and heavy goods vehicles), the restrictions are more stringent, with a requirement of 12 months off driving for a first unprovoked isolated seizure and 5 years off driving if there is an underlying causative factor.

For epilepsy or multiple seizures, both group 1 and group 2 license holders must remain seizure-free for 12 months before their license can be considered. They must also notify the DVLA. In the case of a stroke or isolated transient ischemic attack (TIA), group 1 license holders need to refrain from driving for 1 month, while group 2 license holders must wait for 12 months before being re-licensed subject to medical evaluation. Multiple TIAs require 3 months off driving for both groups.

Isolated vasovagal syncope requires no driving restriction for group 1 license holders, but group 2 license holders must refrain from driving for 3 months. Both groups must notify the DVLA. If syncope is caused by a reversible and treated condition, group 1 license holders need 4 weeks off driving, while group 2 license holders require 3 months. In the case of an isolated syncopal episode with an unknown cause, group 1 license holders must refrain from driving for 6 months, while group 2 license holders will have their license refused or revoked for 12 months.

For patients who continue to drive against medical advice, the GMC (General Medical Council) has provided guidance on how doctors should manage the situation. Doctors should explain to the patient why they are not allowed to drive and inform them of their legal duty to notify the DVLA or DVA (Driver and Vehicle Agency in Northern Ireland). Doctors should also record the advice given to the patient in their medical record

According to the current guidelines from NICE, alteplase is recommended as a thrombolysis treatment for acute ischaemic stroke. For more information, you can refer to the NICE guidelines on stroke and transient ischaemic attack in individuals over the age of 16.

Multiple sclerosis is a condition characterized by the demyelination of nerve cells in the brain and spinal cord. It is an autoimmune disease caused by recurring inflammation, primarily affecting individuals in early adulthood. The condition is more prevalent in females, with a ratio of 3:2 compared to males.

There are several risk factors associated with multiple sclerosis. These include being of Caucasian race, living at a greater distance from the equator (as the risk tends to increase further away), having a family history of the disease (with approximately 20% of patients having an affected relative), and smoking. Interestingly, the rates of relapse tend to decrease during pregnancy.

Multiple sclerosis can present in three main patterns. The most common is relapsing and remitting MS, where individuals experience periods without symptoms followed by relapses. This accounts for 80% of cases at the time of diagnosis. Another pattern is primary progressive MS, where symptoms develop and worsen from the beginning with few remissions. This is seen in approximately 10-15% of cases at diagnosis. Lastly, there is secondary progressive MS, which occurs after a relapsing/remitting phase. In this pattern, symptoms worsen with fewer remissions, and it affects around 50% of individuals with relapsing/remitting MS within 10 years of diagnosis.

Certain factors can indicate a more favorable prognosis for individuals with multiple sclerosis. These include having a relapsing/remitting course of the disease, being female, experiencing sensory symptoms, and having an early age at onset.

The ulnar nerve provides innervation to several muscles in the hand. These include the palmar interossei, dorsal interossei, medial two lumbricals, and abductor digiti minimi. On the other hand, the median nerve innervates the opponens pollicis, lateral two lumbricals, and flexor pollicis brevis. Lastly, the radial nerve is responsible for innervating the extensor digitorum muscle.

Alteplase (rt-pA) is a recommended treatment for acute ischaemic stroke in adults if it is initiated within 4.5 hours of the onset of stroke symptoms. It is crucial to exclude intracranial haemorrhage through appropriate imaging techniques before starting the treatment. The initial dose of alteplase is 0.9 mg/kg, with a maximum of 90 mg. This dose is administered intravenously over a period of 60 minutes. The first 10% of the dose is given through intravenous injection, while the remaining amount is administered through intravenous infusion. For more information, please refer to the NICE guidelines on stroke and transient ischaemic attack in individuals aged 16 and above.

The symptoms and signs of strokes can vary depending on which blood vessel is affected. Here is a summary of the main symptoms based on the territory affected:

Anterior cerebral artery: This can cause weakness on the opposite side of the body, with the leg and shoulder being more affected than the arm, hand, and face. There may also be minimal loss of sensation on the opposite side of the body. Other symptoms can include difficulty speaking (dysarthria), language problems (aphasia), apraxia (difficulty with limb movements), urinary incontinence, and changes in behavior and personality.

Middle cerebral artery: This can lead to weakness on the opposite side of the body, with the face and arm being more affected than the leg. There may also be a loss of sensation on the opposite side of the body. Depending on the dominant hemisphere of the brain, there may be difficulties with expressive or receptive language (dysphasia). In the non-dominant hemisphere, there may be neglect of the opposite side of the body.

Posterior cerebral artery: This can cause a loss of vision on the opposite side of both eyes (homonymous hemianopia). There may also be defects in a specific quadrant of the visual field. In some cases, there may be a syndrome affecting the thalamus on the opposite side of the body.

It’s important to note that these are just general summaries and individual cases may vary. If you suspect a stroke, it’s crucial to seek immediate medical attention.

Patients with Parkinson’s disease (PD) typically exhibit the following clinical features:

– Hypokinesia (reduced movement)
– Bradykinesia (slow movement)
– Rest tremor (usually occurring at a rate of 4-6 cycles per second)
– Rigidity (increased muscle tone and ‘cogwheel rigidity’)

Other commonly observed clinical features include:

– Gait disturbance (characterized by a shuffling gait and loss of arm swing)
– Loss of facial expression
– Monotonous, slurred speech
– Micrographia (small, cramped handwriting)
– Increased salivation and dribbling
– Difficulty with fine movements

Initially, these signs are typically seen on one side of the body at the time of diagnosis, but they progressively worsen and may eventually affect both sides. In later stages of the disease, additional clinical features may become evident, including:

– Postural instability
– Cognitive impairment
– Orthostatic hypotension

Although PD primarily affects movement, patients often experience psychiatric issues such as depression and dementia. Autonomic disturbances and pain can also occur, leading to significant disability and reduced quality of life for the affected individual. Additionally, family members and caregivers may also be indirectly affected by the disease.

This patient presents with a classic case of temporal arteritis, also known as giant cell arteritis (GCA). Temporal arteritis is a chronic condition characterized by inflammation in the walls of medium and large arteries, specifically granulomatous inflammation. It typically affects individuals who are over 50 years old.

The clinical features of temporal arteritis include headache, tenderness in the scalp, jaw claudication, and episodes of sudden blindness or amaurosis fugax (usually occurring in one eye). Some patients may also experience systemic symptoms such as fever, fatigue, loss of appetite, weight loss, and depression.

Temporal arteritis is often associated with polymyalgia rheumatica (PMR) in about 50% of cases. PMR is characterized by stiffness, aching, and tenderness in the upper arms (bilateral) and pain in the pelvic girdle.

Visual loss is an early and significant complication of temporal arteritis, and once it occurs, it rarely improves. Therefore, early treatment with high-dose corticosteroids is crucial to prevent further visual loss and other ischemic complications. If temporal arteritis is suspected, immediate initiation of high-dose glucocorticosteroid treatment (40 – 60 mg prednisolone daily) is necessary. It is also important to arrange an urgent referral for specialist evaluation, including a same-day ophthalmology assessment for those with visual symptoms, and a temporal artery biopsy.

The normal intracranial pressure (ICP) for an adult lying down is typically between 5 and 15 mmHg.

Further Reading:

Intracranial pressure (ICP) refers to the pressure within the craniospinal compartment, which includes neural tissue, blood, and cerebrospinal fluid (CSF). Normal ICP for a supine adult is 5-15 mmHg. The body maintains ICP within a narrow range through shifts in CSF production and absorption. If ICP rises, it can lead to decreased cerebral perfusion pressure, resulting in cerebral hypoperfusion, ischemia, and potentially brain herniation.

The cranium, which houses the brain, is a closed rigid box in adults and cannot expand. It is made up of 8 bones and contains three main components: brain tissue, cerebral blood, and CSF. Brain tissue accounts for about 80% of the intracranial volume, while CSF and blood each account for about 10%. The Monro-Kellie doctrine states that the sum of intracranial volumes is constant, so an increase in one component must be offset by a decrease in the others.

There are various causes of raised ICP, including hematomas, neoplasms, brain abscesses, edema, CSF circulation disorders, venous sinus obstruction, and accelerated hypertension. Symptoms of raised ICP include headache, vomiting, pupillary changes, reduced cognition and consciousness, neurological signs, abnormal fundoscopy, cranial nerve palsy, hemiparesis, bradycardia, high blood pressure, irregular breathing, focal neurological deficits, seizures, stupor, coma, and death.

Measuring ICP typically requires invasive procedures, such as inserting a sensor through the skull. Management of raised ICP involves a multi-faceted approach, including antipyretics to maintain normothermia, seizure control, positioning the patient with a 30º head up tilt, maintaining normal blood pressure, providing analgesia, using drugs to lower ICP (such as mannitol or saline), and inducing hypocapnoeic vasoconstriction through hyperventilation. If these measures are ineffective, second-line therapies like barbiturate coma, optimised hyperventilation, controlled hypothermia, or decompressive craniectomy may be considered.

The NICE recommendations for managing patients with suspected TIA are as follows:

– Offer aspirin (300 mg daily) to individuals who have experienced a suspected TIA, unless there are contraindications. This treatment should be started immediately.
– Immediately refer individuals who have had a suspected TIA for specialist assessment and investigation. They should be seen within 24 hours of the onset of symptoms.
– Avoid using scoring systems, such as ABCD2, to assess the risk of subsequent stroke or determine the urgency of referral for individuals with suspected or confirmed TIA.
– Provide secondary prevention measures, in addition to aspirin, as soon as possible after confirming the diagnosis of TIA.

The NICE recommendations for imaging in individuals with suspected TIA or acute non-disabling stroke are as follows:

– Do not offer CT brain scanning to individuals with suspected TIA, unless there is clinical suspicion of an alternative diagnosis that CT could detect.
– After a specialist assessment in the TIA clinic, consider performing an MRI (including diffusion-weighted and blood-sensitive sequences) to determine the area of ischemia, detect hemorrhage, or identify alternative pathologies. If an MRI is conducted, it should be done on the same day as the assessment.
– Carotid imaging is necessary for all individuals with TIA who, after specialist assessment, are considered candidates for carotid endarterectomy. This imaging should be done urgently.

For more information, refer to the NICE guidelines on stroke and transient ischaemic attack in individuals over 16 years old: diagnosis and initial management.

A subarachnoid haemorrhage (SAH) occurs when there is spontaneous bleeding into the subarachnoid space and is often a catastrophic event. The incidence of SAH is 9 cases per 100,000 people per year, and it typically affects individuals between the ages of 35 and 65.

The majority of SAH cases (80%) are caused by the rupture of berry (saccular) aneurysms, while 15% are caused by arteriovenous malformations (AVM). In less than 5% of cases, no specific cause can be found. Berry aneurysms are associated with polycystic kidneys, Ehlers-Danlos Syndrome, and coarctation of the aorta.

There are several risk factors for SAH, including smoking, hypertension, bleeding disorders, alcohol misuse, mycotic aneurysm, and a family history of the condition.

Patients with SAH typically experience a sudden and severe occipital headache, often described as the worst headache of my life. This may be accompanied by vomiting, collapse, seizures, and coma. Clinical signs of SAH include neck stiffness, a positive Kernig’s sign, and focal neurological abnormalities. Fundoscopy may reveal subhyaloid retinal haemorrhages in approximately 25% of patients.

Re-bleeding occurs in 30-40% of patients who survive the initial episode, with the highest risk occurring between 7 and 14 days after the initial event.

Untreated SAH has a mortality rate of nearly 50% within the first eight weeks following presentation. Prolonged coma is associated with a 100% mortality rate.

The first-line investigation for SAH is a CT head scan, which can detect over 95% of cases if performed within the first 24 hours. The sensitivity of the CT scan increases to nearly 100% if performed within 6 hours of symptom onset. If the CT scan is negative and there are no contraindications, a lumbar puncture (LP) should be performed at least 12 hours after the onset of headache to diagnose SAH. Approximately 3% of patients with a negative CT scan will be confirmed to have had an SAH following an LP.

Status epilepticus is a condition characterized by continuous seizure activity lasting for 5 minutes or more without the return of consciousness, or recurrent seizures (2 or more) without a period of neurological recovery in between. In this particular patient’s case, his history of chronic alcohol abuse, homelessness, and likely impaired nutrition necessitates the administration of intravenous thiamine in the form of Pabrinex. Additionally, a second dose of benzodiazepine should be given, and his blood glucose levels should be urgently checked.

The management of status epilepticus involves several general measures, which are outlined in the following table:

1st stage (Early status, 0-10 minutes):
– Secure the airway and provide resuscitation
– Administer oxygen
– Assess cardiorespiratory function
– Establish intravenous access

2nd stage (0-30 minutes):
– Implement regular monitoring
– Consider the possibility of non-epileptic status
– Initiate emergency antiepileptic drug (AED) therapy
– Perform emergency investigations
– Administer glucose (50 ml of 50% solution) and/or intravenous thiamine as Pabrinex if there are indications of alcohol abuse or impaired nutrition
– Treat severe acidosis if present

3rd stage (0-60 minutes):
– Determine the underlying cause of status epilepticus
– Notify the anaesthetist and intensive care unit (ITU)
– Identify and treat any medical complications
– Consider pressor therapy when appropriate

4th stage (30-90 minutes):
– Transfer the patient to the intensive care unit
– Establish intensive care and EEG monitoring
– Initiate intracranial pressure monitoring if necessary
– Start initial long-term, maintenance AED therapy

Emergency investigations include blood tests for gases, glucose, renal and liver function, calcium and magnesium levels, full blood count (including platelets), blood clotting, and AED drug levels. Serum and urine samples should be saved for future analysis, including toxicology if the cause of convulsive status epilepticus is uncertain. A chest radiograph may be performed to evaluate the possibility of aspiration. Additional investigations, such as brain imaging or lumbar puncture, depend on the clinical circumstances.

Monitoring during the management of status epilepticus involves regular neurological observations and measurements of pulse, blood pressure, and temperature.

The patient’s history aligns with a generalized tonic-clonic seizure. The observer of the incident provided a detailed description, which is crucial in diagnosing epilepsy.

Diagnosing epilepsy can sometimes rely solely on the patient’s history. It is common to ask the patient to maintain a seizure diary to identify patterns and potential triggers. Additionally, EEG tests, along with an MRI scan or CT scan of the brain, can provide further insight into the type and possible cause of the seizures.

The symptoms and signs of strokes can vary depending on which blood vessel is affected. Here is a summary of the main symptoms based on the territory affected:

Anterior cerebral artery: This can cause weakness on the opposite side of the body, with the leg and shoulder being more affected than the arm, hand, and face. There may also be minimal loss of sensation on the opposite side of the body. Other symptoms can include difficulty speaking (dysarthria), language problems (aphasia), apraxia (difficulty with limb movements), urinary incontinence, and changes in behavior and personality.

Middle cerebral artery: This can lead to weakness on the opposite side of the body, with the face and arm being more affected than the leg. There may also be a loss of sensation on the opposite side of the body. Depending on the dominant hemisphere of the brain, there may be difficulties with expressive or receptive language (dysphasia). In the non-dominant hemisphere, there may be neglect of the opposite side of the body.

Posterior cerebral artery: This can cause a loss of vision on the opposite side of both eyes (homonymous hemianopia). There may also be defects in a specific quadrant of the visual field. In some cases, there may be a syndrome affecting the thalamus on the opposite side of the body.

It’s important to note that these are just general summaries and individual cases may vary. If you suspect a stroke, it’s crucial to seek immediate medical attention.

The current algorithm for the treatment of a convulsing child, known as APLS, is as follows:

Step 1 (5 minutes after the start of convulsion):
If a child has been convulsing for 5 minutes or more, the initial dose of benzodiazepine should be administered. This can be done by giving Lorazepam at a dose of 0.1 mg/kg intravenously (IV) or intraosseously (IO) if vascular access is available. Alternatively, buccal midazolam at a dose of 0.5 mg/kg or rectal diazepam at a dose of 0.5 mg/kg can be given if vascular access is not available.

Step 2 (10 minutes after the start of Step 1):
If the convulsion continues for a further 10 minutes, a second dose of benzodiazepine should be given. It is also important to summon senior help at this point.

Step 3 (10 minutes after the start of Step 2):
At this stage, it is necessary to involve senior help to reassess the child and provide guidance on further management. The recommended approach is as follows:
– If the child is not already on phenytoin, a phenytoin infusion should be initiated. This involves administering 20 mg/kg of phenytoin intravenously over a period of 20 minutes.
– If the child is already taking phenytoin, phenobarbitone can be used as an alternative. The recommended dose is 20 mg/kg administered intravenously over 20 minutes.
– In the meantime, rectal paraldehyde can be considered at a dose of 0.8 ml/kg of the 50:50 mixture while preparing the infusion.

Step 4 (20 minutes after the start of Step 3):
If the child is still experiencing convulsions at this stage, it is crucial to have an anaesthetist present. A rapid sequence induction with thiopental is recommended for further management.

Please note that this algorithm is subject to change based on individual patient circumstances and the guidance of medical professionals.

The symptoms and signs of strokes can vary depending on which blood vessel is affected. Here is a summary of the main symptoms based on the territory affected:

Anterior cerebral artery: This can cause weakness on the opposite side of the body, with the leg and shoulder being more affected than the arm, hand, and face. There may also be minimal loss of sensation on the opposite side of the body. Other symptoms can include difficulty speaking (dysarthria), language problems (aphasia), apraxia (difficulty with limb movements), urinary incontinence, and changes in behavior and personality.

Middle cerebral artery: This can lead to weakness on the opposite side of the body, with the face and arm being more affected than the leg. There may also be a loss of sensation on the opposite side of the body. Depending on the dominant hemisphere of the brain, there may be difficulties with expressive or receptive language (dysphasia). In the non-dominant hemisphere, there may be neglect of the opposite side of the body.

Posterior cerebral artery: This can cause a loss of vision on the opposite side of both eyes (homonymous hemianopia). There may also be defects in a specific quadrant of the visual field. In some cases, there may be a syndrome affecting the thalamus on the opposite side of the body.

It’s important to note that these are just general summaries and individual cases may vary. If you suspect a stroke, it’s crucial to seek immediate medical attention.

Dementia is a condition characterized by a decline in cognitive abilities, such as memory, thinking, and reasoning, that is severe enough to interfere with daily functioning. There are several different causes of dementia, but the leading cause is Alzheimer’s disease. Alzheimer’s disease is a progressive brain disorder that affects memory, thinking, and behavior. It is the most common cause of dementia, accounting for approximately 60-80% of cases.

Further Reading:

Dementia is a progressive and irreversible clinical syndrome characterized by cognitive and behavioral symptoms. These symptoms include memory loss, impaired reasoning and communication, personality changes, and reduced ability to carry out daily activities. The decline in cognition affects multiple domains of intellectual functioning and is not solely due to normal aging.

To diagnose dementia, a person must have impairment in at least two cognitive domains that significantly impact their daily activities. This impairment cannot be explained by delirium or other major psychiatric disorders. Early-onset dementia refers to dementia that develops before the age of 65.

The most common cause of dementia is Alzheimer’s disease, accounting for 50-75% of cases. Other causes include vascular dementia, dementia with Lewy bodies, and frontotemporal dementia. Less common causes include Parkinson’s disease dementia, Huntington’s disease, prion disease, and metabolic and endocrine disorders.

There are several risk factors for dementia, including age, mild cognitive impairment, genetic predisposition, excess alcohol intake, head injury, depression, learning difficulties, diabetes, obesity, hypertension, smoking, Parkinson’s disease, low social engagement, low physical activity, low educational attainment, hearing impairment, and air pollution.

Assessment of dementia involves taking a history from the patient and ideally a family member or close friend. The person’s current level of cognition and functional capabilities should be compared to their baseline level. Physical examination, blood tests, and cognitive assessment tools can also aid in the diagnosis.

Differential diagnosis for dementia includes normal age-related memory changes, mild cognitive impairment, depression, delirium, vitamin deficiencies, hypothyroidism, adverse drug effects, normal pressure hydrocephalus, and sensory deficits.

Management of dementia involves a multi-disciplinary approach that includes non-pharmacological and pharmacological measures. Non-pharmacological interventions may include driving assessment, modifiable risk factor management, and non-pharmacological therapies to promote cognition and independence. Drug treatments for dementia should be initiated by specialists and may include acetylcholinesterase inhibitors, memantine, and antipsychotics in certain cases.

In summary, dementia is a progressive and irreversible syndrome characterized by cognitive and behavioral symptoms. It has various causes and risk factors, and its management involves a multi-disciplinary approach.

If a child who is experiencing convulsions reaches step 3 of the APLS algorithm and has already been given phenytoin as part of their ongoing treatment, it is recommended to initiate a phenobarbitone infusion. This infusion should be administered at a dosage of 20 mg/kg over a period of 30 to 60 minutes.

Dementia with Lewy bodies (DLB) is characterized by several key features, including spontaneous fluctuations in cognitive abilities, visual hallucinations, and Parkinsonism. Visual hallucinations are particularly prevalent in DLB and Parkinson’s disease dementia, which are considered to be part of the same spectrum. While visual hallucinations can occur in other forms of dementia, they are less frequently observed.

Further Reading:

Dementia is a progressive and irreversible clinical syndrome characterized by cognitive and behavioral symptoms. These symptoms include memory loss, impaired reasoning and communication, personality changes, and reduced ability to carry out daily activities. The decline in cognition affects multiple domains of intellectual functioning and is not solely due to normal aging.

To diagnose dementia, a person must have impairment in at least two cognitive domains that significantly impact their daily activities. This impairment cannot be explained by delirium or other major psychiatric disorders. Early-onset dementia refers to dementia that develops before the age of 65.

The most common cause of dementia is Alzheimer’s disease, accounting for 50-75% of cases. Other causes include vascular dementia, dementia with Lewy bodies, and frontotemporal dementia. Less common causes include Parkinson’s disease dementia, Huntington’s disease, prion disease, and metabolic and endocrine disorders.

There are several risk factors for dementia, including age, mild cognitive impairment, genetic predisposition, excess alcohol intake, head injury, depression, learning difficulties, diabetes, obesity, hypertension, smoking, Parkinson’s disease, low social engagement, low physical activity, low educational attainment, hearing impairment, and air pollution.

Assessment of dementia involves taking a history from the patient and ideally a family member or close friend. The person’s current level of cognition and functional capabilities should be compared to their baseline level. Physical examination, blood tests, and cognitive assessment tools can also aid in the diagnosis.

Differential diagnosis for dementia includes normal age-related memory changes, mild cognitive impairment, depression, delirium, vitamin deficiencies, hypothyroidism, adverse drug effects, normal pressure hydrocephalus, and sensory deficits.

Management of dementia involves a multi-disciplinary approach that includes non-pharmacological and pharmacological measures. Non-pharmacological interventions may include driving assessment, modifiable risk factor management, and non-pharmacological therapies to promote cognition and independence. Drug treatments for dementia should be initiated by specialists and may include acetylcholinesterase inhibitors, memantine, and antipsychotics in certain cases.

In summary, dementia is a progressive and irreversible syndrome characterized by cognitive and behavioral symptoms. It has various causes and risk factors, and its management involves a multi-disciplinary approach.

Tonsillar herniation occurs when the cerebellar tonsils are pushed through the foramen magnum. This condition is characterized by a decrease in consciousness, respiratory arrest, and flaccid paralysis.

Further Reading:

Intracranial pressure (ICP) refers to the pressure within the craniospinal compartment, which includes neural tissue, blood, and cerebrospinal fluid (CSF). Normal ICP for a supine adult is 5-15 mmHg. The body maintains ICP within a narrow range through shifts in CSF production and absorption. If ICP rises, it can lead to decreased cerebral perfusion pressure, resulting in cerebral hypoperfusion, ischemia, and potentially brain herniation.

The cranium, which houses the brain, is a closed rigid box in adults and cannot expand. It is made up of 8 bones and contains three main components: brain tissue, cerebral blood, and CSF. Brain tissue accounts for about 80% of the intracranial volume, while CSF and blood each account for about 10%. The Monro-Kellie doctrine states that the sum of intracranial volumes is constant, so an increase in one component must be offset by a decrease in the others.

There are various causes of raised ICP, including hematomas, neoplasms, brain abscesses, edema, CSF circulation disorders, venous sinus obstruction, and accelerated hypertension. Symptoms of raised ICP include headache, vomiting, pupillary changes, reduced cognition and consciousness, neurological signs, abnormal fundoscopy, cranial nerve palsy, hemiparesis, bradycardia, high blood pressure, irregular breathing, focal neurological deficits, seizures, stupor, coma, and death.

Measuring ICP typically requires invasive procedures, such as inserting a sensor through the skull. Management of raised ICP involves a multi-faceted approach, including antipyretics to maintain normothermia, seizure control, positioning the patient with a 30º head up tilt, maintaining normal blood pressure, providing analgesia, using drugs to lower ICP (such as mannitol or saline), and inducing hypocapnoeic vasoconstriction through hyperventilation. If these measures are ineffective, second-line therapies like barbiturate coma, optimised hyperventilation, controlled hypothermia, or decompressive craniectomy may be considered.

Henry’s law describes the correlation between the quantity of dissolved gas in a liquid and its partial pressure above the liquid. According to Henry’s law, the amount of gas dissolved in a liquid is directly proportional to the partial pressure of that gas above the liquid. In the case of nitrogen narcosis, as the patient descends deeper into the water, the pressure increases, causing more nitrogen to dissolve in the bloodstream. As the patient ascends, the pressure decreases, leading to a decrease in the amount of dissolved nitrogen and improvement in symptoms.

Further Reading:

Decompression illness (DCI) is a term that encompasses both decompression sickness (DCS) and arterial gas embolism (AGE). When diving underwater, the increasing pressure causes gases to become more soluble and reduces the size of gas bubbles. As a diver ascends, nitrogen can come out of solution and form gas bubbles, leading to decompression sickness or the bends. Boyle’s and Henry’s gas laws help explain the changes in gases during changing pressure.

Henry’s law states that the amount of gas that dissolves in a liquid is proportional to the partial pressure of the gas. Divers often use atmospheres (ATM) as a measure of pressure, with 1 ATM being the pressure at sea level. Boyle’s law states that the volume of gas is inversely proportional to the pressure. As pressure increases, volume decreases.

Decompression sickness occurs when nitrogen comes out of solution as a diver ascends. The evolved gas can physically damage tissue by stretching or tearing it as bubbles expand, or by provoking an inflammatory response. Joints and spinal nervous tissue are commonly affected. Symptoms of primary damage usually appear immediately or soon after a dive, while secondary damage may present hours or days later.

Arterial gas embolism occurs when nitrogen bubbles escape into the arterial circulation and cause distal ischemia. The consequences depend on where the embolism lodges, ranging from tissue ischemia to stroke if it lodges in the cerebral arterial circulation. Mechanisms for distal embolism include pulmonary barotrauma, right to left shunt, and pulmonary filter overload.

Clinical features of decompression illness vary, but symptoms often appear within six hours of a dive. These can include joint pain, neurological symptoms, chest pain or breathing difficulties, rash, vestibular problems, and constitutional symptoms. Factors that increase the risk of DCI include diving at greater depth, longer duration, multiple dives close together, problems with ascent, closed rebreather circuits, flying shortly after diving, exercise shortly after diving, dehydration, and alcohol use.

Diagnosis of DCI is clinical, and investigations depend on the presentation. All patients should receive high flow oxygen, and a low threshold for ordering a chest X-ray should be maintained. Hydration is important, and IV fluids may be necessary. Definitive treatment is recompression therapy in a hyperbaric oxygen chamber, which should be arranged as soon as possible. Entonox should not be given, as it will increase the pressure effect in air spaces.

This woman is displaying symptoms and signs that are in line with a diagnosis of meningococcal septicaemia. In the United Kingdom, the majority of cases of meningococcal septicaemia are caused by Neisseria meningitidis group B.

The implementation of a vaccination program for Neisseria meningitidis group C has significantly reduced the prevalence of this particular type. However, a vaccine for group B disease is currently undergoing clinical trials and is not yet accessible for widespread use.

Parkinson’s disease (PD) is a progressive neurodegenerative condition that occurs when the dopamine-containing cells in the substantia nigra die. It is estimated that PD affects around 100-180 individuals per 100,000 of the population, which translates to approximately 6-11 people per 6,000 individuals in the general population of the UK. The annual incidence of PD is between 4-20 cases per 100,000 people. The prevalence of PD increases with age, with approximately 0.5% of individuals aged 65 to 74 being affected and 1-2% of individuals aged 75 and older. Additionally, PD is more prevalent and has a higher incidence in males.

The classic clinical features of Parkinson’s disease include hypokinesia, which refers to a poverty of movement, and bradykinesia, which is characterized by slowness of movement. Rest tremor, typically occurring at a rate of 4-6 cycles per second, is also commonly observed in PD patients. Another clinical feature is rigidity, which is characterized by increased muscle tone and a phenomenon known as cogwheel rigidity.

Subfalcine herniation occurs when a mass in one side of the brain causes the cingulate gyrus to be pushed under the falx cerebri. This condition often leads to specific neurological symptoms. These symptoms include a motor deficit in the lower limb on the opposite side of the body, bladder incontinence, motor and sensory deficits on the same side of the body as the herniation, and difficulty with speech (dysarthria).

Further Reading:

Intracranial pressure (ICP) refers to the pressure within the craniospinal compartment, which includes neural tissue, blood, and cerebrospinal fluid (CSF). Normal ICP for a supine adult is 5-15 mmHg. The body maintains ICP within a narrow range through shifts in CSF production and absorption. If ICP rises, it can lead to decreased cerebral perfusion pressure, resulting in cerebral hypoperfusion, ischemia, and potentially brain herniation.

The cranium, which houses the brain, is a closed rigid box in adults and cannot expand. It is made up of 8 bones and contains three main components: brain tissue, cerebral blood, and CSF. Brain tissue accounts for about 80% of the intracranial volume, while CSF and blood each account for about 10%. The Monro-Kellie doctrine states that the sum of intracranial volumes is constant, so an increase in one component must be offset by a decrease in the others.

There are various causes of raised ICP, including hematomas, neoplasms, brain abscesses, edema, CSF circulation disorders, venous sinus obstruction, and accelerated hypertension. Symptoms of raised ICP include headache, vomiting, pupillary changes, reduced cognition and consciousness, neurological signs, abnormal fundoscopy, cranial nerve palsy, hemiparesis, bradycardia, high blood pressure, irregular breathing, focal neurological deficits, seizures, stupor, coma, and death.

Measuring ICP typically requires invasive procedures, such as inserting a sensor through the skull. Management of raised ICP involves a multi-faceted approach, including antipyretics to maintain normothermia, seizure control, positioning the patient with a 30º head up tilt, maintaining normal blood pressure, providing analgesia, using drugs to lower ICP (such as mannitol or saline), and inducing hypocapnoeic vasoconstriction through hyperventilation. If these measures are ineffective, second-line therapies like barbiturate coma, optimised hyperventilation, controlled hypothermia, or decompressive craniectomy may be considered.

If a person is unable to stand up or walk, even with their eyes open, it is likely that the cause of their vertigo is central in nature. Additional features that increase suspicion of a central cause include focal neurology, prolonged and severe vertigo (although this can also be seen in vestibular neuronitis or Meniere’s disease), new-onset headache or recent trauma, a normal head impulse test, and the presence of cardiovascular risk factors.

Further Reading:

Vertigo is a symptom characterized by a false sensation of movement, such as spinning or rotation, in the absence of any actual physical movement. It is not a diagnosis itself, but rather a description of the sensation experienced by the individual. Dizziness, on the other hand, refers to a perception of disturbed or impaired spatial orientation without a false sense of motion.

Vertigo can be classified as either peripheral or central. Peripheral vertigo is more common and is caused by problems in the inner ear that affect the labyrinth or vestibular nerve. Examples of peripheral vertigo include BPPV, vestibular neuritis, labyrinthitis, and Meniere’s disease. Central vertigo, on the other hand, is caused by pathology in the brain, such as in the brainstem or cerebellum. Examples of central vertigo include migraine, TIA and stroke, cerebellar tumor, acoustic neuroma, and multiple sclerosis.

There are certain features that can help differentiate between peripheral and central vertigo. Peripheral vertigo is often associated with severe nausea and vomiting, hearing loss or tinnitus, and a positive head impulse test. Central vertigo may be characterized by prolonged and severe vertigo, new-onset headache, recent trauma, cardiovascular risk factors, inability to stand or walk with eyes open, focal neurological deficit, and a negative head impulse test.

Nystagmus, an involuntary eye movement, can also provide clues about the underlying cause of vertigo. Central causes of vertigo often have nystagmus that is direction-changing on lateral gaze, purely vertical or torsional, not suppressed by visual fixation, non-fatigable, and commonly large amplitude. Peripheral causes of vertigo often have horizontal nystagmus with a torsional component that does not change direction with gaze, disappears with fixation of the gaze, and may have large amplitude early in the course of Meniere’s disease or vestibular neuritis.

There are various causes of vertigo, including viral labyrinthitis, vestibular neuritis, benign paroxysmal positional vertigo, Meniere’s disease, vertebrobasilar ischemia, and acoustic neuroma. Each of these disorders has its own unique characteristics and may be associated with other symptoms such as hearing loss, tinnitus, or neurological deficits.

When assessing a patient with vertigo, it is important to perform a cardiovascular and neurological examination, including assessing cranial nerves, cerebellar signs, eye movements, gait, coordination, and evidence of peripheral

Febrile convulsions are harmless, generalized seizures that occur in otherwise healthy children who have a fever due to an infection outside the brain. To diagnose febrile convulsions, the child must be developing normally, the seizure should last less than 20 minutes, have no complex features, and not cause any lasting abnormalities.

The prognosis for febrile convulsions is generally positive. There is a 30 to 50% chance of experiencing recurrent febrile convulsions, with a 10% risk of recurrence within the first 24 hours. The likelihood of developing long-term epilepsy is around 6%.

Complex febrile convulsions are characterized by certain factors. These include focal seizures, seizures lasting longer than 15 minutes, experiencing more than one convulsion during a single fever episode, or the child being left with a focal neurological deficit.

Overall, febrile convulsions are typically harmless and do not cause any lasting damage.

Wernicke’s area is situated in the dominant cerebral hemisphere temporal lobe. Specifically, it can be found in the posterior section of the superior temporal gyrus.

This area is responsible for comprehending both written and spoken language. It allows individuals to read a sentence, understand its meaning, and articulate it verbally.

When Wernicke’s area is damaged, patients may be able to string words together fluently, but the resulting phrases lack coherence and meaning. This condition is known as receptive aphasia or Wernicke’s aphasia.

When there is damage to the facial nerve in the LMN, the patient will experience paralysis in the forehead and will be unable to wrinkle their brow. However, in an upper motor neuron lesion, the frontalis muscle is not affected, so the patient can still furrow their brow normally and their ability to close their eyes and blink is not affected. Lower motor neuron lesions affect the final part of the nerve pathway to all branches of the facial nerve, resulting in paralysis of the forehead and the rest of the face on that side. It is important to note that the speed of onset may provide some clues about the cause of the lesion, but it does not help determine the specific location of the damage.

Further Reading:

Bell’s palsy is a condition characterized by sudden weakness or paralysis of the facial nerve, resulting in facial muscle weakness or drooping. The exact cause is unknown, but it is believed to be related to viral infections such as herpes simplex or varicella zoster. It is more common in individuals aged 15-45 years and those with diabetes, obesity, hypertension, or upper respiratory conditions. Pregnancy is also a risk factor.

Diagnosis of Bell’s palsy is typically based on clinical symptoms and ruling out other possible causes of facial weakness. Symptoms include rapid onset of unilateral facial muscle weakness, drooping of the eyebrow and corner of the mouth, loss of the nasolabial fold, otalgia, difficulty chewing or dry mouth, taste disturbance, eye symptoms such as inability to close the eye completely, dry eye, eye pain, and excessive tearing, numbness or tingling of the cheek and mouth, speech articulation problems, and hyperacusis.

When assessing a patient with facial weakness, it is important to consider other possible differentials such as stroke, facial nerve tumors, Lyme disease, granulomatous diseases, Ramsay Hunt syndrome, mastoiditis, and chronic otitis media. Red flags for these conditions include insidious and painful onset, duration of symptoms longer than 3 months with frequent relapses, pre-existing risk factors, systemic illness or fever, vestibular or hearing abnormalities, and other cranial nerve involvement.

Management of Bell’s palsy involves the use of steroids, eye care advice, and reassurance. Steroids, such as prednisolone, are recommended for individuals presenting within 72 hours of symptom onset. Eye care includes the use of lubricating eye drops, eye ointment at night, eye taping if unable to close the eye at night, wearing sunglasses, and avoiding dusty environments. Reassurance is important as the majority of patients make a complete recovery within 3-4 months. However, some individuals may experience sequelae such as facial asymmetry, gustatory lacrimation, inadequate lid closure, brow ptosis, drooling, and hemifacial spasms.

Antiviral treatments are not currently recommended as a standalone treatment for Bell’s palsy, but they may be given in combination with corticosteroids on specialist advice. Referral to an ophthalmologist is necessary if the patient has eye symptoms such as pain, irritation, or itch.

Hyperventilation leads to the constriction of blood vessels in the brain, which in turn reduces the flow and volume of blood in the brain, ultimately decreasing intracranial pressure (ICP). This is because hyperventilation lowers the levels of carbon dioxide (PaCO2) in the blood, resulting in an increase in pH and causing the arteries in the brain to constrict and reduce blood flow. As a result, cerebral blood volume and ICP decrease. The effects of hyperventilation are immediate, but they gradually diminish over a period of 6-24 hours as the brain adjusts its bicarbonate levels to normalize pH. However, caution must be exercised when discontinuing hyperventilation after a prolonged period, as the sudden increase in PaCO2 can lead to a rapid rise in cerebral blood flow and a detrimental increase in ICP.

Further Reading:

Intracranial pressure (ICP) refers to the pressure within the craniospinal compartment, which includes neural tissue, blood, and cerebrospinal fluid (CSF). Normal ICP for a supine adult is 5-15 mmHg. The body maintains ICP within a narrow range through shifts in CSF production and absorption. If ICP rises, it can lead to decreased cerebral perfusion pressure, resulting in cerebral hypoperfusion, ischemia, and potentially brain herniation.

The cranium, which houses the brain, is a closed rigid box in adults and cannot expand. It is made up of 8 bones and contains three main components: brain tissue, cerebral blood, and CSF. Brain tissue accounts for about 80% of the intracranial volume, while CSF and blood each account for about 10%. The Monro-Kellie doctrine states that the sum of intracranial volumes is constant, so an increase in one component must be offset by a decrease in the others.

There are various causes of raised ICP, including hematomas, neoplasms, brain abscesses, edema, CSF circulation disorders, venous sinus obstruction, and accelerated hypertension. Symptoms of raised ICP include headache, vomiting, pupillary changes, reduced cognition and consciousness, neurological signs, abnormal fundoscopy, cranial nerve palsy, hemiparesis, bradycardia, high blood pressure, irregular breathing, focal neurological deficits, seizures, stupor, coma, and death.

Measuring ICP typically requires invasive procedures, such as inserting a sensor through the skull. Management of raised ICP involves a multi-faceted approach, including antipyretics to maintain normothermia, seizure control, positioning the patient with a 30º head up tilt, maintaining normal blood pressure, providing analgesia, using drugs to lower ICP (such as mannitol or saline), and inducing hypocapnoeic vasoconstriction through hyperventilation. If these measures are ineffective, second-line therapies like barbiturate coma, optimised hyperventilation, controlled hypothermia, or decompressive craniectomy may be considered.

The recommended dosage of buccal midazolam for treating a child experiencing seizures is 0.5 mg per kilogram of body weight.