A summary of the vessels involved in different types of myocardial infarction, along with the corresponding ECG leads and the location of the infarction.

For instance, an anteroseptal infarction involving the left anterior descending artery is indicated by ECG leads V1-V3. Similarly, an anterior infarction involving the left anterior descending artery is indicated by leads V3-V4.

In cases of anterolateral infarctions, both the left anterior descending artery and the left circumflex artery are involved, and this is reflected in ECG leads V5-V6. An extensive anterior infarction involving the left anterior descending artery is indicated by leads V1-V6.

Lateral infarcts involving the left circumflex artery are indicated by leads I, II, aVL, and V6. Inferior infarctions, on the other hand, involve either the right coronary artery (in 80% of cases) or the left circumflex artery (in 20% of cases), and this is shown by leads II, III, and aVF.

In the case of a right ventricular infarction, the right coronary artery is involved, and this is indicated by leads V1 and V4R. Lastly, a posterior infarction involving the right coronary artery is shown by leads V7-V9.

Mastoiditis can lead to the development of cranial nerve palsies, specifically affecting the trigeminal (CN V), abducens (CN VI), and facial (CN VII) nerves. This occurs when the infection spreads to the petrous apex of the temporal bone, where these nerves are located. The close proximity of the sixth cranial nerve and the trigeminal ganglion, separated only by the dura mater, can result in inflammation and subsequent nerve damage. Additionally, the facial nerve is at risk as it passes through the mastoid via the facial canal.

Further Reading:

Mastoiditis is an infection of the mastoid air cells, which are located in the mastoid process of the skull. It is usually caused by the spread of infection from the middle ear. The most common organism responsible for mastoiditis is Streptococcus pneumoniae, but other bacteria and fungi can also be involved. The infection can spread to surrounding structures, such as the meninges, causing serious complications like meningitis or cerebral abscess.

Mastoiditis can be classified as acute or chronic. Acute mastoiditis is a rare complication of acute otitis media, which is inflammation of the middle ear. It is characterized by severe ear pain, fever, swelling and redness behind the ear, and conductive deafness. Chronic mastoiditis is usually associated with chronic suppurative otitis media or cholesteatoma and presents with recurrent episodes of ear pain, headache, and fever.

Mastoiditis is more common in children, particularly those between 6 and 13 months of age. Other risk factors include immunocompromised patients, those with intellectual impairment or communication difficulties, and individuals with cholesteatoma.

Diagnosis of mastoiditis involves a physical examination, blood tests, ear swab for culture and sensitivities, and imaging studies like contrast-enhanced CT or MRI. Treatment typically involves referral to an ear, nose, and throat specialist, broad-spectrum intravenous antibiotics, pain relief, and myringotomy (a procedure to drain fluid from the middle ear).

Complications of mastoiditis are rare but can be serious. They include intracranial abscess, meningitis, subperiosteal abscess, neck abscess, venous sinus thrombosis, cranial nerve palsies, hearing loss, labyrinthitis, extension to the zygoma, and carotid artery arteritis. However, most patients with mastoiditis have a good prognosis and do not experience long-term ear problems.

Common causes for different acid-base disorders.

Respiratory alkalosis can be caused by hyperventilation, such as during periods of anxiety. It can also be a result of conditions like pulmonary embolism, CNS disorders (such as stroke or encephalitis), altitude, pregnancy, or the early stages of aspirin overdose.

Respiratory acidosis is often associated with chronic obstructive pulmonary disease (COPD) or life-threatening asthma. It can also occur due to pulmonary edema, sedative drug overdose (such as opiates or benzodiazepines), neuromuscular disease, obesity, or other respiratory conditions.

Metabolic alkalosis can be caused by vomiting, potassium depletion (often due to diuretic usage), Cushing’s syndrome, or Conn’s syndrome.

Metabolic acidosis with a raised anion gap can occur due to lactic acidosis (such as in cases of hypoxemia, shock, sepsis, or infarction) or ketoacidosis (such as in diabetes, starvation, or alcohol excess). It can also be a result of renal failure or poisoning (such as in late stages of aspirin overdose, methanol or ethylene glycol ingestion).

Metabolic acidosis with a normal anion gap can be caused by conditions like renal tubular acidosis, diarrhea, ammonium chloride ingestion, or adrenal insufficiency.

The occurrence of schizophrenia is consistent across all social classes. It affects individuals from all walks of life without discrimination. The likelihood of developing schizophrenia over one’s lifetime is 1%, and this probability remains the same for both men and women. However, it is worth noting that men tend to experience the onset of symptoms at a younger age compared to women, with the average age of onset falling between 15 and 45 years.

There is a recognized genetic predisposition for schizophrenia, meaning that certain individuals may have a higher likelihood of developing the condition due to their genetic makeup. The risk of schizophrenia affecting first-degree relatives, such as siblings or parents, is approximately 10%. Furthermore, the risk of children being affected by schizophrenia increases to 40%.

When considering the impact of genetics on schizophrenia, it is interesting to note that monozygotic twins, who share identical genetic material, have a concordance rate of around 50%. This suggests that genetic factors play a significant role in the development of the condition.

Tragically, approximately 10% of individuals suffering from schizophrenia ultimately die by suicide, particularly during the early stages of the illness. This highlights the importance of providing appropriate support and intervention to individuals with schizophrenia to prevent such devastating outcomes.

In this case, the patient opens his eyes to voice, which corresponds to a score of 3 on the eye opening component. The patient localizes to pain, indicating a purposeful motor response, which corresponds to a score of 5 on the motor response component. However, the patient’s speech is slurred and he appears disoriented, suggesting an impaired verbal response. This would correspond to a score of 4 on the verbal response component.

To calculate the GCS, we sum up the scores from each component. In this case, the patient’s GCS would be 3 + 4 + 5 = 12

Further Reading:

Indications for CT Scanning in Head Injuries (Adults):
– CT head scan should be performed within 1 hour if any of the following features are present:
– GCS < 13 on initial assessment in the ED
– GCS < 15 at 2 hours after the injury on assessment in the ED
– Suspected open or depressed skull fracture
– Any sign of basal skull fracture (haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, Battle’s sign)
– Post-traumatic seizure
– New focal neurological deficit
– > 1 episode of vomiting

Indications for CT Scanning in Head Injuries (Children):
– CT head scan should be performed within 1 hour if any of the features in List 1 are present:
– Suspicion of non-accidental injury
– Post-traumatic seizure but no history of epilepsy
– GCS < 14 on initial assessment in the ED for children more than 1 year of age
– Paediatric GCS < 15 on initial assessment in the ED for children under 1 year of age
– At 2 hours after the injury, GCS < 15
– Suspected open or depressed skull fracture or tense fontanelle
– Any sign of basal skull fracture (haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, Battle’s sign)
– New focal neurological deficit
– For children under 1 year, presence of bruise, swelling or laceration of more than 5 cm on the head

– CT head scan should be performed within 1 hour if none of the above features are present but two or more of the features in List 2 are present:
– Loss of consciousness lasting more than 5 minutes (witnessed)
– Abnormal drowsiness
– Three or more discrete episodes of vomiting
– Dangerous mechanism of injury (high-speed road traffic accident, fall from a height.

The administration of propofol can result in venodilation, leading to a significant drop in blood pressure. This effect is particularly significant in patients who are already experiencing unstable blood flow.

Further Reading:

There are four commonly used induction agents in the UK: propofol, ketamine, thiopentone, and etomidate.

Propofol is a 1% solution that produces significant venodilation and myocardial depression. It can also reduce cerebral perfusion pressure. The typical dose for propofol is 1.5-2.5 mg/kg. However, it can cause side effects such as hypotension, respiratory depression, and pain at the site of injection.

Ketamine is another induction agent that produces a dissociative state. It does not display a dose-response continuum, meaning that the effects do not necessarily increase with higher doses. Ketamine can cause bronchodilation, which is useful in patients with asthma. The initial dose for ketamine is 0.5-2 mg/kg, with a typical IV dose of 1.5 mg/kg. Side effects of ketamine include tachycardia, hypertension, laryngospasm, unpleasant hallucinations, nausea and vomiting, hypersalivation, increased intracranial and intraocular pressure, nystagmus and diplopia, abnormal movements, and skin reactions.

Thiopentone is an ultra-short acting barbiturate that acts on the GABA receptor complex. It decreases cerebral metabolic oxygen and reduces cerebral blood flow and intracranial pressure. The adult dose for thiopentone is 3-5 mg/kg, while the child dose is 5-8 mg/kg. However, these doses should be halved in patients with hypovolemia. Side effects of thiopentone include venodilation, myocardial depression, and hypotension. It is contraindicated in patients with acute porphyrias and myotonic dystrophy.

Etomidate is the most haemodynamically stable induction agent and is useful in patients with hypovolemia, anaphylaxis, and asthma. It has similar cerebral effects to thiopentone. The dose for etomidate is 0.15-0.3 mg/kg. Side effects of etomidate include injection site pain, movement disorders, adrenal insufficiency, and apnoea. It is contraindicated in patients with sepsis due to adrenal suppression.

Ectopic production of ACTH is linked to small-cell lung cancer and can lead to Cushing’s syndrome. It can also be observed in cases of pancreatic cancer and thymoma.

Hypertrophic pulmonary osteoarthropathy (HPOA) is characterized by the presence of periostitis, arthritis, and finger clubbing. On plain X-ray, subperiosteal new bone formation can be detected. This condition primarily affects the long bones and often causes pain. It is most commonly associated with squamous cell lung cancer and pulmonary adenocarcinoma.

Gynaecomastia, which is the enlargement of breast tissue in males, can occur as a result of squamous cell lung cancer. In these cases, it tends to be accompanied by pain.

Rarely, squamous cell lung cancer can cause ectopic production of TSH, leading to hyperthyroidism.

Carcinoid syndrome is a condition that arises from carcinoid tumors, which secrete serotonin and kallikreins. This syndrome manifests as episodes of flushing, diarrhea, and bronchospasm. Additionally, 50% of patients develop a secondary restrictive cardiomyopathy. Carcinoid tumors can occur in various locations, with the small intestine being the most common site. Other locations include the lungs (bronchial adenoma), rectum, appendix, and stomach.

Stevens-Johnson syndrome is a severe and potentially deadly form of erythema multiforme. It can be triggered by anything that causes erythema multiforme, but it is most commonly seen as a reaction to medication within 1-3 weeks of starting treatment. Initially, there may be symptoms like fever, fatigue, joint pain, and digestive issues, followed by the development of severe mucocutaneous lesions that are blistering and ulcerating.

Stevens-Johnson syndrome and toxic epidermal necrolysis are considered to be different stages of the same mucocutaneous disease, with toxic epidermal necrolysis being more severe. The extent of epidermal detachment is used to differentiate between the two. In Stevens-Johnson syndrome, less than 10% of the body surface area is affected by epidermal detachment, while in toxic epidermal necrolysis, it is greater than 30%. An overlap syndrome occurs when detachment affects between 10-30% of the body surface area.

Several drugs can potentially cause Stevens-Johnson syndrome and toxic epidermal necrolysis, including tetracyclines, penicillins, vancomycin, sulphonamides, NSAIDs, and barbiturates.

Traveller’s diarrhoea (TD) is a prevalent illness that affects travellers all around the globe. It is estimated that up to 50% of Europeans who spend two or more weeks in developing regions experience this condition. TD is characterized by the passage of three or more loose stools within a 24-hour period. Alongside this, individuals often experience abdominal cramps, nausea, and bloating.

Bacteria are the primary culprits behind approximately 80% of TD cases, while viruses and protozoa account for the remaining cases. Among the various organisms, Enterotoxigenic Escherichia coli (ETEC) is the most frequently identified cause.

In summary, TD is a common ailment that affects travellers, manifesting as loose stools, abdominal discomfort, and other associated symptoms. Bacterial infections, particularly ETEC, are the leading cause of this condition.

An anal fissure is a tear in the wall of the anal mucosa that exposes the circular muscle layer. The majority of these tears occur in the posterior midline, and they are often caused by the passage of a large, hard stool after a period of constipation. If multiple fissures are present, it may indicate an underlying condition such as Crohn’s disease or tuberculosis.

Both men and women are equally affected by anal fissures, and they are most commonly seen in individuals in their thirties. The typical symptoms of an anal fissure include intense, sharp pain during bowel movements, which can last for up to an hour after passing stool. Additionally, there may be spots of bright red blood on the toilet paper when wiping, and a history of constipation.

The initial management approach for an anal fissure involves non-operative measures such as using stool softeners and bulking agents. To alleviate the intense anal pain, analgesics and topical local anesthetics may be prescribed. According to a recent meta-analysis, first-line therapy should involve the use of topical GTN or diltiazem, with botulinum toxin being used as a rescue treatment if necessary (Modern perspectives in the treatment of chronic anal fissures. Ann R Coll Surg Engl. 2007 Jul;89(5):472-8.)

Sphincterotomy, a surgical procedure, should be reserved for cases where the fissure does not heal with conservative measures. It has a success rate of 90%.

According to NICE, hyoscine butylbromide is recommended as the initial medication for managing nausea and vomiting in individuals with obstructive bowel disorders who are in the last days of life. NICE provides guidance on how to handle these symptoms in the final days of life, which includes assessing the potential causes of nausea and vomiting in the dying person. This may involve considering factors such as certain medications, recent chemotherapy or radiotherapy, psychological causes, biochemical causes like hypercalcemia, raised intracranial pressure, gastrointestinal motility disorder, ileus, or bowel obstruction.

It is important to discuss the available options for treating nausea and vomiting with the dying person and their loved ones. Non-pharmacological methods should also be considered when managing these symptoms in someone in the last days of life. When selecting medications for nausea and vomiting, factors such as the likely cause and reversibility of the symptoms, potential side effects (including sedation), other symptoms the person may be experiencing, and the desired balancing of effects when managing other symptoms should be taken into account. Additionally, compatibility and potential drug interactions with other medications the person is taking should be considered.

For individuals in the last days of life with obstructive bowel disorders who have nausea or vomiting, hyoscine butylbromide is recommended as the first-line pharmacological treatment. If the symptoms do not improve within 24 hours of starting treatment with hyoscine butylbromide, octreotide may be considered as an alternative option.

For more information, refer to the NICE guidance on the care of dying adults in the last days of life. https://www.nice.org.uk/guidance/ng31

Supraventricular tachycardia (SVT) is the most common arrhythmia that occurs in children and infants, causing cardiovascular instability. According to the current APLS guidelines, if a patient with SVT shows no signs of shock and remains stable, initial attempts should be made to use vagal maneuvers. If these maneuvers are unsuccessful, the following steps are recommended:

– Administer an initial dose of 100 mcg/kg of adenosine.
– After two minutes, if the child is still in stable SVT, administer another dose of 200 mcg/kg of adenosine.
– After an additional two minutes, if the child remains in stable SVT, administer another dose of 300 mcg/kg of adenosine.

If these measures do not resolve the SVT, the guidelines suggest considering the following options:

– Administer adenosine at a dose of 400-500 mcg/kg.
– Perform a synchronous DC shock.
– Administer amiodarone.

When using amiodarone, the initial dose should be 5-10 mg/kg given over a period of 20 minutes to 2 hours. This should be followed by a continuous infusion of 300 mcg/kg/hour, with adjustments made based on the response, increasing by 1.5 mg/kg/hour. The total infusion rate should not exceed 1.2 g in a 24-hour period.

If defibrillation is necessary for the treatment of SVT in children, it should be performed as a DC synchronous shock at a dosage of 1-2 J/kg.

Gout and pseudogout are both characterized by the presence of crystal deposits in the joints that are affected. Gout occurs when urate crystals are deposited, while pseudogout occurs when calcium pyrophosphate crystals are deposited. Under a microscope, these crystals can be distinguished by their appearance. Urate crystals are needle-shaped and negatively birefringent, while calcium pyrophosphate crystals are brick-shaped and positively birefringent.

Gout can affect any joint in the body, but it most commonly manifests in the hallux metatarsophalangeal joint, which is the joint at the base of the big toe. This joint is affected in approximately 50% of gout cases. On the other hand, pseudogout primarily affects the larger joints, such as the knee.

A PaO2/FiO2 ratio ranging from 100 mmHg to 200 mmHg indicates the presence of moderate Acute Respiratory Distress Syndrome (ARDS).

Further Reading:

ARDS is a severe form of lung injury that occurs in patients with a predisposing risk factor. It is characterized by the onset of respiratory symptoms within 7 days of a known clinical insult, bilateral opacities on chest X-ray, and respiratory failure that cannot be fully explained by cardiac failure or fluid overload. Hypoxemia is also present, as indicated by a specific threshold of the PaO2/FiO2 ratio measured with a minimum requirement of positive end-expiratory pressure (PEEP) ≥5 cm H2O. The severity of ARDS is classified based on the PaO2/FiO2 ratio, with mild, moderate, and severe categories.

Lung protective ventilation is a set of measures aimed at reducing lung damage that may occur as a result of mechanical ventilation. Mechanical ventilation can cause lung damage through various mechanisms, including high air pressure exerted on lung tissues (barotrauma), over distending the lung (volutrauma), repeated opening and closing of lung units (atelectrauma), and the release of inflammatory mediators that can induce lung injury (biotrauma). These mechanisms collectively contribute to ventilator-induced lung injury (VILI).

The key components of lung protective ventilation include using low tidal volumes (5-8 ml/kg), maintaining inspiratory pressures (plateau pressure) below 30 cm of water, and allowing for permissible hypercapnia. However, there are some contraindications to lung protective ventilation, such as an unacceptable level of hypercapnia, acidosis, and hypoxemia. These factors need to be carefully considered when implementing lung protective ventilation strategies in patients with ARDS.

Thiopental sodium is a barbiturate with a very short duration of action. It is primarily used to induce anesthesia. Barbiturates are believed to primarily affect synapses by reducing the sensitivity of postsynaptic receptors to neurotransmitters and by interfering with the release of neurotransmitters from presynaptic neurons.

Thiopental sodium specifically binds to a unique site associated with a chloride ionophore at the GABAA receptor, which is responsible for the opening of chloride ion channels. This binding increases the length of time that the chloride ionophore remains open. As a result, the inhibitory effect of GABA on postsynaptic neurons in the thalamus is prolonged.

In summary, thiopental sodium acts as a short-acting barbiturate that is commonly used to induce anesthesia. It affects synapses by reducing postsynaptic receptor sensitivity and interfering with neurotransmitter release. By binding to a specific site at the GABAA receptor, thiopental sodium prolongs the inhibitory effect of GABA in the thalamus.

The three sites most frequently used for IO access are the proximal tibia, distal tibia, and distal femur. The proximal tibia is located 2 cm below the tibial tuberosity, while the distal tibia is just above the medial malleolus. The distal femur site is situated 2 cm above the condyle in the midline. These sites are commonly chosen for IO access. However, there are also less commonly used sites such as the proximal humerus (above the surgical neck) and the iliac crest. It is important to note that the proximal humerus may be challenging to palpate in children and is typically not used in those under 5 years of age. Additionally, accessing the sternum requires a specialist device.

Further Reading:

Intraosseous (IO) cannulation is a technique used to gain urgent intravenous (IV) access in patients where traditional IV access is difficult to obtain. It involves injecting fluid or drugs directly into the medullary cavity of the bone. This procedure can be performed in both adult and pediatric patients and is commonly used in emergency situations.

There are different types of IO needles available, including manual IO needles and device-powered IO needles such as the EZ-IO. These tools allow healthcare professionals to access the bone and administer necessary medications or fluids quickly and efficiently.

The most commonly used sites for IO cannulation are the tibia (shinbone) and the femur (thighbone). In some cases, the proximal humerus (upper arm bone) may also be used. However, there are certain contraindications to IO cannulation that should be considered. These include fractures of the bone to be cannulated, overlying skin infections or a high risk of infection (such as burns), conditions like osteogenesis imperfecta or osteoporosis, ipsilateral vascular injury, and coagulopathy.

While IO cannulation is a valuable technique, there are potential complications that healthcare professionals should be aware of. These include superficial skin infections, osteomyelitis (infection of the bone), skin necrosis, growth plate injury (in pediatric patients), fractures, failure to access or position the needle correctly, extravasation (leakage of fluid or medication into surrounding tissues), and compartment syndrome (a rare but serious condition that can occur if there is an undiagnosed fracture).

Overall, IO cannulation is a useful method for gaining urgent IV access in patients when traditional methods are challenging. However, it is important for healthcare professionals to be aware of the potential complications and contraindications associated with this procedure.

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.

This patient presents with a noticeable mass at the top of the right lung, which is clearly visible on the chest X-ray. Based on the symptoms and clinical presentation, it is highly likely that this is a Pancoast tumor, and the overall diagnosis is Pancoast syndrome.

A Pancoast tumor is a type of tumor that develops at the apex of either the right or left lung. It typically spreads to nearby tissues such as the ribs and vertebrae. The majority of Pancoast tumors are classified as non-small cell cancers.

Pancoast syndrome occurs when the tumor invades various structures and tissues around the thoracic inlet. This includes the invasion of the cervical sympathetic plexus on the same side as the tumor, leading to the development of Horner’s syndrome. Additionally, there may be reflex sympathetic dystrophy in the arm on the affected side, resulting in increased sensitivity to touch and changes in the skin.

Patients with Pancoast syndrome may also experience shoulder and arm pain due to the tumor invading the brachial plexus roots C8-T1. This can lead to muscle wasting in the hand and tingling sensations in the inner side of the arm. In some cases, there may be involvement of the unilateral recurrent laryngeal nerve, causing unilateral vocal cord paralysis and resulting in a hoarse voice and/or a bovine cough. Phrenic nerve involvement is less common but can also occur.

Horner’s syndrome, which is a key feature of Pancoast syndrome, is caused by compression of the sympathetic chain from the hypothalamus to the orbit. The three main symptoms of Horner’s syndrome are drooping of the eyelid (ptosis), constriction of the pupil (pupillary miosis), and lack of sweating on the forehead (anhydrosis).

Verapamil is a type of calcium-channel blocker that is commonly used to treat irregular heart rhythms and chest pain. It is important to note that verapamil should not be taken at the same time as beta-blockers like atenolol and bisoprolol. This is because when these medications are combined, they can have a negative impact on the heart’s ability to contract and the heart rate, leading to a significant drop in blood pressure, slow heart rate, impaired conduction between the upper and lower chambers of the heart, heart failure (due to decreased ability of the heart to pump effectively), and even a pause in the heart’s normal rhythm. For more information, you can refer to the section on verapamil interactions in the British National Formulary (BNF).

Vascular dementia is the second most common form of dementia, accounting for approximately 25% of all cases. It occurs when the brain is damaged due to various factors, such as major strokes, multiple smaller strokes that go unnoticed (known as multi-infarct), or chronic changes in smaller blood vessels (referred to as subcortical dementia). The term vascular cognitive impairment (VCI) is increasingly used to encompass this range of diseases.

Unlike Alzheimer’s disease, which has a gradual and subtle onset, vascular dementia can occur suddenly and typically shows a series of stepwise increases in symptom severity. The presentation and progression of the disease can vary significantly.

There are certain features that suggest a vascular cause of dementia. These include a history of transient ischemic attacks (TIAs) or cardiovascular disease, the presence of focal neurological abnormalities, prominent memory impairment in the early stages of the disease, early onset of gait disturbance and unsteadiness, frequent unprovoked falls in the early stages, bladder symptoms (such as incontinence) without any identifiable urological condition in the early stages, and seizures.

This patient is showing a slightly elevated heart rate and respiratory rate, as well as a slightly reduced urine output. These signs indicate that the patient has experienced a class II haemorrhage at this point. It is important to be able to recognize the degree of blood loss based on vital sign and mental status abnormalities. The Advanced Trauma Life Support (ATLS) haemorrhagic shock classification provides a way to link the amount of blood loss to expected physiological responses in a healthy 70 kg patient. In a 70 kg male patient, the total circulating blood volume is approximately five liters, which accounts for about 7% of their total body weight.

The ATLS haemorrhagic shock classification is summarized as follows:

CLASS I:
– Blood loss: Up to 750 mL
– Blood loss (% blood volume): Up to 15%
– Pulse rate: Less than 100 bpm
– Systolic BP: Normal
– Pulse pressure: Normal (or increased)
– Respiratory rate: 14-20 breaths per minute
– Urine output: Greater than 30 mL/hr
– CNS/mental status: Slightly anxious

CLASS II:
– Blood loss: 750-1500 mL
– Blood loss (% blood volume): 15-30%
– Pulse rate: 100-120 bpm
– Systolic BP: Normal
– Pulse pressure: Decreased
– Respiratory rate: 20-30 breaths per minute
– Urine output: 20-30 mL/hr
– CNS/mental status: Mildly anxious

CLASS III:
– Blood loss: 1500-2000 mL
– Blood loss (% blood volume): 30-40%
– Pulse rate: 120-140 bpm
– Systolic BP: Decreased
– Pulse pressure: Decreased
– Respiratory rate: 30-40 breaths per minute
– Urine output: 5-15 mL/hr
– CNS/mental status: Anxious, confused

CLASS IV:
– Blood loss: More than 2000 mL
– Blood loss (% blood volume): More than 40%
– Pulse rate: More than 140 bpm
– Systolic BP: Decreased
– Pulse pressure: Decreased
– Respiratory rate: More than 40 breaths per minute
– Urine output: Negligible
– CNS/mental status: Confused, lethargic

Croup, also known as laryngo-tracheo-bronchitis, is typically caused by the parainfluenza virus. Other viruses such as rhinovirus, influenza, and respiratory syncytial viruses can also be responsible. Before the onset of stridor, there is usually a mild cold-like illness that lasts for 1-2 days. Symptoms reach their peak at 1-3 days, with the cough often being worse at night. A milder cough may persist for another 7-10 days.

A barking cough is a characteristic symptom of croup, but it does not indicate the severity of the condition. To reduce airway swelling, dexamethasone and prednisolone are commonly used. Nebulized budesonide can be an alternative if the child is experiencing vomiting. However, it’s important to note that steroids do not shorten the duration of the illness. In severe cases, nebulized adrenaline can be administered.

Hospitalization for croup is rare and typically reserved for children who are experiencing increasing respiratory distress or showing signs of drowsiness/agitation. The Westley croup score is a useful tool for assessing the child’s condition and making appropriate management decisions. Children with moderate (score 2-7) or severe croup (score >7) may require hospital admission. On the other hand, many children with mild croup (score 0-1) can be safely discharged and treated at home.

The Westley croup score is determined based on the following criteria: the presence of stridor when agitated, the severity of retractions, air entry, SaO2 levels below 92%, and the child’s conscious level. In this particular case, the child’s Westley croup score is 2 points, indicating the presence of stridor when agitated and mild retractions.

Excessive intake of lithium is linked to the development of low anion gap acidosis. In cases of lithium overdose, a common outcome is the occurrence of low anion gap acidosis.

Further Reading:

Arterial blood gases (ABG) are an important diagnostic tool used to assess a patient’s acid-base status and respiratory function. When obtaining an ABG sample, it is crucial to prioritize safety measures to minimize the risk of infection and harm to the patient. This includes performing hand hygiene before and after the procedure, wearing gloves and protective equipment, disinfecting the puncture site with alcohol, using safety needles when available, and properly disposing of equipment in sharps bins and contaminated waste bins.

To reduce the risk of harm to the patient, it is important to test for co-lateral circulation using the modified Allen test for radial artery puncture. Additionally, it is essential to inquire about any occlusive vascular conditions or anticoagulation therapy that may affect the procedure. The puncture site should be checked for signs of infection, injury, or previous surgery. After the test, pressure should be applied to the puncture site or the patient should be advised to apply pressure for at least 5 minutes to prevent bleeding.

Interpreting ABG results requires a systematic approach. The core set of results obtained from a blood gas analyser includes the partial pressures of oxygen and carbon dioxide, pH, bicarbonate concentration, and base excess. These values are used to assess the patient’s acid-base status.

The pH value indicates whether the patient is in acidosis, alkalosis, or within the normal range. A pH less than 7.35 indicates acidosis, while a pH greater than 7.45 indicates alkalosis.

The respiratory system is assessed by looking at the partial pressure of carbon dioxide (pCO2). An elevated pCO2 contributes to acidosis, while a low pCO2 contributes to alkalosis.

The metabolic aspect is assessed by looking at the bicarbonate (HCO3-) level and the base excess. A high bicarbonate concentration and base excess indicate alkalosis, while a low bicarbonate concentration and base excess indicate acidosis.

Analyzing the pCO2 and base excess values can help determine the primary disturbance and whether compensation is occurring. For example, a respiratory acidosis (elevated pCO2) may be accompanied by metabolic alkalosis (elevated base excess) as a compensatory response.

The anion gap is another important parameter that can help determine the cause of acidosis. It is calculated by subtracting the sum of chloride and bicarbonate from the sum of sodium and potassium.

Ketamine administration can lead to various side effects, including nystagmus and diplopia. Other potential side effects include tachycardia, hypertension, laryngospasm, unpleasant hallucinations or emergence phenomena, nausea and vomiting, hypersalivation, increased intracranial and intraocular pressure, and abnormal tonic-clonic movements.

Further Reading:

There are four commonly used induction agents in the UK: propofol, ketamine, thiopentone, and etomidate.

Propofol is a 1% solution that produces significant venodilation and myocardial depression. It can also reduce cerebral perfusion pressure. The typical dose for propofol is 1.5-2.5 mg/kg. However, it can cause side effects such as hypotension, respiratory depression, and pain at the site of injection.

Ketamine is another induction agent that produces a dissociative state. It does not display a dose-response continuum, meaning that the effects do not necessarily increase with higher doses. Ketamine can cause bronchodilation, which is useful in patients with asthma. The initial dose for ketamine is 0.5-2 mg/kg, with a typical IV dose of 1.5 mg/kg. Side effects of ketamine include tachycardia, hypertension, laryngospasm, unpleasant hallucinations, nausea and vomiting, hypersalivation, increased intracranial and intraocular pressure, nystagmus and diplopia, abnormal movements, and skin reactions.

Thiopentone is an ultra-short acting barbiturate that acts on the GABA receptor complex. It decreases cerebral metabolic oxygen and reduces cerebral blood flow and intracranial pressure. The adult dose for thiopentone is 3-5 mg/kg, while the child dose is 5-8 mg/kg. However, these doses should be halved in patients with hypovolemia. Side effects of thiopentone include venodilation, myocardial depression, and hypotension. It is contraindicated in patients with acute porphyrias and myotonic dystrophy.

Etomidate is the most haemodynamically stable induction agent and is useful in patients with hypovolemia, anaphylaxis, and asthma. It has similar cerebral effects to thiopentone. The dose for etomidate is 0.15-0.3 mg/kg. Side effects of etomidate include injection site pain, movement disorders, adrenal insufficiency, and apnoea. It is contraindicated in patients with sepsis due to adrenal suppression.

Radiation to the trapezius ridge is a distinct symptom of acute pericarditis. The patient in question exhibits characteristics that align with a diagnosis of pericarditis. Pericarditis is a common condition affecting the pericardium, and it is often considered as a potential cause for chest pain. It is worth noting that the specific radiation of pain to the trapezius ridge is highly indicative of pericarditis, as it occurs when the phrenic nerve, which also innervates the trapezius muscle, becomes irritated while passing through the pericardium.

Further Reading:

Pericarditis is an inflammation of the pericardium, which is the protective sac around the heart. It can be acute, lasting less than 6 weeks, and may present with chest pain, cough, dyspnea, flu-like symptoms, and a pericardial rub. The most common causes of pericarditis include viral infections, tuberculosis, bacterial infections, uremia, trauma, and autoimmune diseases. However, in many cases, the cause remains unknown. Diagnosis is based on clinical features, such as chest pain, pericardial friction rub, and electrocardiographic changes. Treatment involves symptom relief with nonsteroidal anti-inflammatory drugs (NSAIDs), and patients should avoid strenuous activity until symptoms improve. Complicated cases may require treatment for the underlying cause, and large pericardial effusions may need urgent drainage. In cases of purulent effusions, antibiotic therapy is necessary, and steroid therapy may be considered for pericarditis related to autoimmune disorders or if NSAIDs alone are ineffective.

Borderline personality disorder is characterized by a range of clinical features. These include having unstable relationships, experiencing undue anger, and having variable moods. Individuals with this disorder often struggle with chronic boredom and may have doubts about their personal identity. They also tend to have an intolerance of being left alone and may engage in self-injury. Additionally, they exhibit impulsive behavior that can be damaging to themselves.

The first-rank symptoms of schizophrenia, as described by Kurt Schneider, include auditory hallucinations such as hearing 3rd person voices discussing the patient, experiencing thought echo, and receiving commentary on one’s actions. Additionally, passivity phenomena may occur, such as thought insertion, thought withdrawal, thought broadcast, and feelings of thoughts and actions being under external control. Delusions, which can be primary or secondary, are also common in schizophrenia.

On the other hand, chronic schizophrenia is characterized by negative symptoms. These include poor motivation and self-care, social withdrawal, depression, flat and blunted affect, emotional incongruity, decreased activity, and poverty of thought and speech. These symptoms are often present in individuals with chronic schizophrenia.

Isoniazid has the potential to induce acute hepatitis, but it is not considered a known cause of cholestatic jaundice. On the other hand, there are several drugs that have been identified as culprits for cholestatic jaundice. These include nitrofurantoin, erythromycin, cephalosporins, verapamil, NSAIDs, ACE inhibitors, tricyclic antidepressants, phenytoin, azathioprine, carbamazepine, oral contraceptive pills, diazepam, ketoconazole, and tamoxifen. It is important to be aware of these medications and their potential side effects in order to ensure patient safety.

During CPR of a hypothermic patient, it is important to follow specific guidelines. If the patient’s core temperature is below 30ºC, resuscitation drugs, such as adrenaline, should be withheld. Once the core temperature rises above 30ºC, cardiac arrest drugs can be administered. However, if the patient’s temperature is between 30-35ºC, the interval for administering cardiac arrest drugs should be doubled. For example, adrenaline should be given every 6-10 minutes instead of the usual 3-5 minutes for a normothermic patient.

Further Reading:

Hypothermic cardiac arrest is a rare situation that requires a tailored approach. Resuscitation is typically prolonged, but the prognosis for young, previously healthy individuals can be good. Hypothermic cardiac arrest may be associated with drowning. Hypothermia is defined as a core temperature below 35ºC and can be graded as mild, moderate, severe, or profound based on the core temperature. When the core temperature drops, basal metabolic rate falls and cell signaling between neurons decreases, leading to reduced tissue perfusion. Signs and symptoms of hypothermia progress as the core temperature drops, initially presenting as compensatory increases in heart rate and shivering, but eventually ceasing as the temperature drops into moderate hypothermia territory.

ECG changes associated with hypothermia include bradyarrhythmias, Osborn waves, prolonged PR, QRS, and QT intervals, shivering artifact, ventricular ectopics, and cardiac arrest. When managing hypothermic cardiac arrest, ALS should be initiated as per the standard ALS algorithm, but with modifications. It is important to check for signs of life, re-warm the patient, consider mechanical ventilation due to chest wall stiffness, adjust dosing or withhold drugs due to slowed drug metabolism, and correct electrolyte disturbances. The resuscitation of hypothermic patients is often prolonged and may continue for a number of hours.

Pulse checks during CPR may be difficult due to low blood pressure, and the pulse check is prolonged to 1 minute for this reason. Drug metabolism is slowed in hypothermic patients, leading to a build-up of potentially toxic plasma concentrations of administered drugs. Current guidance advises withholding drugs if the core temperature is below 30ºC and doubling the drug interval at core temperatures between 30 and 35ºC. Electrolyte disturbances are common in hypothermic patients, and it is important to interpret results keeping the setting in mind. Hypoglycemia should be treated, hypokalemia will often correct as the patient re-warms, ABG analyzers may not reflect the reality of the hypothermic patient, and severe hyperkalemia is a poor prognostic indicator.

Different warming measures can be used to increase the core body temperature, including external passive measures such as removal of wet clothes and insulation with blankets, external active measures such as forced heated air or hot-water immersion, and internal active measures such as inhalation of warm air, warmed intravenous fluids, gastric, bladder, peritoneal and/or pleural lavage and high volume renal haemofilter.

The NICE guidelines for suspected DVT state that if a person scores two points or more on the DVT Wells score, they are likely to have DVT. On the other hand, if a person scores one point or less, it is unlikely that they have DVT.

For individuals who are likely to have DVT, it is recommended to offer a proximal leg vein ultrasound scan with the results available within 4 hours if possible. However, if the ultrasound scan cannot be done within 4 hours, the following steps should be taken: a D-dimer test should be offered, followed by interim therapeutic anticoagulation. It is preferable to choose an anticoagulant that can be continued if DVT is confirmed. Additionally, a proximal leg vein ultrasound scan should be conducted with the results available within 24 hours.

For individuals who are unlikely to have DVT, it is advised to offer a D-dimer test with the results available within 4 hours. If obtaining the results within 4 hours is not possible, interim therapeutic anticoagulation should be provided while awaiting the result. If feasible, an anticoagulant that can be continued if DVT is confirmed should be chosen.

For more information, you can refer to the NICE Clinical Knowledge Summary on deep vein thrombosis.