A 7-year-old girl is brought to the emergency department after being bitten by a bee. She is experiencing swelling in her arm and difficulty breathing, which are signs of anaphylaxis. To treat this condition, the most suitable dose of adrenaline to administer to the patient is 300 micrograms (0.3ml 1 in 1,000) by intramuscular injection.

Further Reading:

Anaphylaxis is a severe and life-threatening hypersensitivity reaction that can have sudden onset and progression. It is characterized by skin or mucosal changes and can lead to life-threatening airway, breathing, or circulatory problems. Anaphylaxis can be allergic or non-allergic in nature.

In allergic anaphylaxis, there is an immediate hypersensitivity reaction where an antigen stimulates the production of IgE antibodies. These antibodies bind to mast cells and basophils. Upon re-exposure to the antigen, the IgE-covered cells release histamine and other inflammatory mediators, causing smooth muscle contraction and vasodilation.

Non-allergic anaphylaxis occurs when mast cells degrade due to a non-immune mediator. The clinical outcome is the same as in allergic anaphylaxis.

The management of anaphylaxis is the same regardless of the cause. Adrenaline is the most important drug and should be administered as soon as possible. The recommended doses for adrenaline vary based on age. Other treatments include high flow oxygen and an IV fluid challenge. Corticosteroids and chlorpheniramine are no longer recommended, while non-sedating antihistamines may be considered as third-line treatment after initial stabilization of airway, breathing, and circulation.

Common causes of anaphylaxis include food (such as nuts, which is the most common cause in children), drugs, and venom (such as wasp stings). Sometimes it can be challenging to determine if a patient had a true episode of anaphylaxis. In such cases, serum tryptase levels may be measured, as they remain elevated for up to 12 hours following an acute episode of anaphylaxis.

The Resuscitation Council (UK) provides guidelines for the management of anaphylaxis, including a visual algorithm that outlines the recommended steps for treatment.

Calcium-channel blocker overdose is a serious condition that should always be taken seriously as it can be potentially life-threatening. The two most dangerous types of calcium channel blockers in overdose are verapamil and diltiazem. These medications work by binding to the alpha-1 subunit of L-type calcium channels, which prevents the entry of calcium into the cells. These channels play a crucial role in the functioning of cardiac myocytes, vascular smooth muscle cells, and islet beta-cells.

Significant toxicity can occur with the ingestion of more than 10 tablets of verapamil (160 mg or 240 mg immediate or sustained-release capsules) or diltiazem (180 mg, 240 mg or 360 mg immediate or sustained-release capsules). In children, even 1-2 tablets of immediate or sustained-release verapamil or diltiazem can be harmful. Symptoms usually appear within 1-2 hours of taking standard preparations, but with slow-release versions, the onset of severe toxicity may be delayed by 12-16 hours, with peak effects occurring after 24 hours.

The main clinical manifestations of calcium-channel blocker overdose include nausea and vomiting, low blood pressure, slow heart rate and first-degree heart block, heart muscle ischemia and stroke, kidney failure, pulmonary edema, and high blood sugar levels.

When managing a patient with calcium-channel blocker overdose, certain bedside investigations are crucial. These include checking blood glucose levels, performing an electrocardiogram (ECG), and obtaining an arterial blood gas sample. Additional investigations that can provide helpful information include assessing urea and electrolyte levels, conducting a chest X-ray to check for pulmonary edema, and performing an echocardiography.

The risk of infection is highest with femoral central lines.

A central venous catheter (CVC) is a type of catheter that is inserted into a large vein in the body, typically in the neck, chest, or groin. It has several important uses, including CVP monitoring, pulmonary artery pressure monitoring, repeated blood sampling, IV access for large volumes of fluids or drugs, TPN administration, dialysis, pacing, and other procedures such as placement of IVC filters or venous stents.

When inserting a central line, it is ideal to use ultrasound guidance to ensure accurate placement. However, there are certain contraindications to central line insertion, including infection or injury to the planned access site, coagulopathy, thrombosis or stenosis of the intended vein, a combative patient, or raised intracranial pressure for jugular venous lines.

The most common approaches for central line insertion are the internal jugular, subclavian, femoral, and PICC (peripherally inserted central catheter) veins. The internal jugular vein is often chosen due to its proximity to the carotid artery, but variations in anatomy can occur. Ultrasound can be used to identify the vessels and guide catheter placement, with the IJV typically lying superficial and lateral to the carotid artery. Compression and Valsalva maneuvers can help distinguish between arterial and venous structures, and doppler color flow can highlight the direction of flow.

In terms of choosing a side for central line insertion, the right side is usually preferred to avoid the risk of injury to the thoracic duct and potential chylothorax. However, the left side can also be used depending on the clinical situation.

Femoral central lines are another option for central venous access, with the catheter being inserted into the femoral vein in the groin. Local anesthesia is typically used to establish a field block, with lidocaine being the most commonly used agent. Lidocaine works by blocking sodium channels and preventing the propagation of action potentials.

In summary, central venous catheters have various important uses and should ideally be inserted using ultrasound guidance. There are contraindications to their insertion, and different approaches can be used depending on the clinical situation. Local anesthesia is commonly used for central line insertion, with lidocaine being the preferred agent.

ATLS guidelines now suggest administering only 1 liter of crystalloid fluid during the initial assessment. If patients do not respond to the crystalloid, it is recommended to quickly transition to blood products. Studies have shown that infusing more than 1.5 liters of crystalloid fluid is associated with higher mortality rates in trauma cases. Therefore, it is advised to prioritize the early use of blood products and avoid large volumes of crystalloid fluid in trauma patients. In cases where it is necessary, massive transfusion should be considered, defined as the transfusion of more than 10 units of blood in 24 hours or more than 4 units of blood in one hour. For patients with evidence of Class III and IV hemorrhage, early resuscitation with blood and blood products in low ratios is recommended.

Based on the findings of significant trials, such as the CRASH-2 study, the use of tranexamic acid is now recommended within 3 hours. This involves administering a loading dose of 1 gram intravenously over 10 minutes, followed by an infusion of 1 gram over eight hours. In some regions, tranexamic acid is also being utilized in the prehospital setting.

This patient is clearly experiencing pyelonephritis with systemic involvement, which may indicate sepsis. According to NICE guidelines, it is recommended to admit individuals to the hospital if they exhibit any symptoms or signs that suggest a more serious illness or condition, such as sepsis. In cases of acute pyelonephritis, it is advisable to consider referring or seeking specialist advice for individuals who are significantly dehydrated or unable to consume oral fluids and medications, pregnant women, those at a higher risk of developing complications (e.g., individuals with known or suspected structural or functional abnormalities of the genitourinary tract or underlying diseases like diabetes mellitus or immunosuppression), and individuals who have recurrent episodes of urinary tract infections (e.g., two or more episodes within a 6-month period). Additionally, it is recommended to consider referral for men who have experienced a single episode without an obvious cause and women with recurrent pyelonephritis. For more information, please refer to the NICE Clinical Knowledge Summary on the management of acute pyelonephritis.

The FeverPAIN score is a scoring system recommended by the current NICE guidelines for assessing acute sore throats. It consists of five items: fever in the last 24 hours, purulence, attendance within three days, inflamed tonsils, and no cough or coryza. Based on the score, recommendations for antibiotic use are as follows: a score of 0-1 indicates an unlikely streptococcal infection, with antibiotics not recommended; a score of 2-3 suggests a 34-40% chance of streptococcus, and delayed prescribing of antibiotics may be considered; a score of 4 or higher indicates a 62-65% chance of streptococcus, and immediate antibiotic use is recommended for severe cases, or a short back-up prescription may be given for 48 hours.

The Fever PAIN score was developed through a study involving 1760 adults and children aged three and over. It was tested in a trial comparing three prescribing strategies: empirical delayed prescribing, score-directed prescribing, and a combination of the score with a near-patient test (NPT) for streptococcus. The use of the score resulted in faster symptom resolution and reduced antibiotic prescribing by one third. The addition of the NPT did not provide any additional benefit.

According to the current NICE guidelines, if antibiotics are necessary, phenoxymethylpenicillin is recommended as the first-choice antibiotic. In cases of true penicillin allergy, clarithromycin can be used as an alternative. For pregnant women with a penicillin allergy, erythromycin is prescribed. It is important to note that the threshold for prescribing antibiotics should be lower for individuals at risk of rheumatic fever and vulnerable groups managed in primary care, such as infants, the elderly, and those who are immunosuppressed or immunocompromised. Antibiotics should not be withheld if the person has severe symptoms and there are concerns about their clinical condition.

The primary cause of fetal death in trauma during pregnancy is maternal shock and maternal death. The second most common cause of fetal death is placental abruption. Abruptio placentae can be identified by the following signs: vaginal bleeding (present in 70% of cases), uterine tenderness, frequent uterine contractions, uterine tetany, and uterine irritability. While uterine ultrasonography can be helpful in diagnosing abruptio placentae, it is not definitive. A CT scan may also show signs of abruptio placenta. It is important to note that abruption can occur even after minor injuries later in pregnancy.

Uterine rupture is a much rarer occurrence but is a catastrophic event that leads to rapid maternal and fetal death without immediate surgical intervention. Signs that suggest uterine rupture include vaginal hemorrhage, abdominal tenderness, abdominal guarding and rigidity, rebound tenderness, profound shock, abnormal fetal lie (such as oblique or transverse lie), easy palpation of fetal parts due to their location outside the uterus, and difficulty in palpating the uterine fundus when there is a rupture.

It is crucial to be aware of these signs and symptoms in order to promptly identify and address any potential complications during pregnancy.

During the first trimester of pregnancy, the use of trimethoprim is linked to an increased risk of neural tube defects because it antagonizes folate. If it is not possible to use an alternative antibiotic, it is recommended that pregnant women taking trimethoprim also take high-dose folic acid. However, the use of trimethoprim in the second and third trimesters of pregnancy is considered safe.

Below is a list outlining the commonly encountered drugs that have adverse effects during pregnancy:

ACE inhibitors (e.g. ramipril): If given in the second and third trimesters, they can cause hypoperfusion, renal failure, and the oligohydramnios sequence.

Aminoglycosides (e.g. gentamicin): They can cause ototoxicity and deafness.

Aspirin: High doses can lead to first-trimester abortions, delayed onset labor, premature closure of the fetal ductus arteriosus, and fetal kernicterus. However, low doses (e.g. 75 mg) do not pose significant risks.

Benzodiazepines (e.g. diazepam): When given late in pregnancy, they can cause respiratory depression and a neonatal withdrawal syndrome.

Calcium-channel blockers: If given in the first trimester, they can cause phalangeal abnormalities. If given in the second and third trimesters, they can lead to fetal growth retardation.

Carbamazepine: It can cause hemorrhagic disease of the newborn and neural tube defects.

Chloramphenicol: It can cause grey baby syndrome.

Corticosteroids: If given in the first trimester, they may cause orofacial clefts.

Danazol: If given in the first trimester, it can cause masculinization of the female fetuses genitals.

Finasteride: Pregnant women should avoid handling finasteride as crushed or broken tablets can be absorbed through the skin and affect male sex organ development.

Haloperidol: If given in the first trimester, it may cause limb malformations. If given in the third trimester, there is an increased risk of extrapyramidal symptoms in the neonate.

Heparin: It can cause maternal bleeding and thrombocytopenia.

Isoniazid: It can lead to maternal liver damage and neuropathy and seizures in the neonate.

Neutropenic sepsis is a serious condition that can occur when a person has low levels of neutrophils, which are a type of white blood cell. This condition can be life-threatening and is often caused by factors such as chemotherapy, immunosuppressive drugs, infections, bone marrow disorders, and nutritional deficiencies.

To diagnose neutropenic sepsis, doctors look for a neutrophil count of 0.5 x 109 per litre or lower in patients undergoing cancer treatment. Additionally, patients must have a temperature higher than 38°C or show other signs and symptoms of significant sepsis.

According to the current guidelines from the National Institute for Health and Care Excellence (NICE), the recommended initial antibiotic treatment for suspected neutropenic sepsis is monotherapy with piperacillin with tazobactam (Tazocin 4.5 g IV). It is important to note that aminoglycosides should not be used as monotherapy or in combination therapy unless there are specific patient-related or local microbiological reasons to do so.

Stable angina is characterized by chest pain in the center of the chest that is triggered by activities such as exercise and emotional stress. The pain may spread to the jaw or left arm and can be relieved by resting for a few minutes. Typically, the pain is brought on by a predictable amount of exertion.

On the other hand, unstable angina is defined by the presence of one or more of the following: angina of effort occurring over a few days with increasing frequency, episodes of angina occurring recurrently and predictably without specific provocation, or an unprovoked and prolonged episode of cardiac chest pain. In unstable angina, the ECG may appear normal or show T wave / ST segment changes, and cardiac enzymes are usually normal.

Prinzmetal angina is a rare form of angina that typically occurs at rest between midnight and early morning. These attacks can be severe and happen in clusters. It is caused by spasms in the coronary arteries, and patients with this condition often have normal coronary arteries.

It is important to note that gastro-esophageal reflux (GORD) is not relevant to this question and is included in the patient’s history to distract the candidate. Typical symptoms of GORD include heartburn and acid regurgitation, and it can also present with non-cardiac chest pain, dyspepsia, and difficulty swallowing.

Lastly, Ludwig’s angina is a serious and potentially life-threatening infection in the submandibular area. It most commonly occurs due to an infection in the floor of the mouth that spreads into the submandibular space.

Discitis is an infection that affects the space between the intervertebral discs in the spine. This condition can have serious consequences, including the formation of abscesses and sepsis. The most common cause of discitis is usually Staphylococcus aureus, but other organisms like Streptococcus viridans and Pseudomonas aeruginosa may be responsible in certain cases, especially in immunocompromised individuals and intravenous drug users. Gram-negative organisms like Escherichia coli and Mycobacterium tuberculosis can also cause discitis, particularly in cases of Pott’s disease.

There are several risk factors that increase the likelihood of developing discitis. These include having undergone spinal surgery (which occurs in about 1-2% of patients post-operatively), having an immunodeficiency, being an intravenous drug user, being under the age of eight, having diabetes mellitus, or having a malignancy.

The typical symptoms of discitis include back or neck pain (which occurs in over 90% of cases), pain that often wakes the patient from sleep, fever (present in 60-70% of cases), and neurological deficits (which can occur in up to 50% of cases). In children, a refusal to walk may also be a symptom.

When diagnosing discitis, magnetic resonance imaging (MRI) is the preferred imaging modality due to its high sensitivity and specificity. It is important to image the entire spine, as discitis often affects multiple levels. Plain radiographs are not very sensitive to the early changes of discitis and may appear normal for 2-4 weeks. Computed tomography (CT) scanning is also not very sensitive in detecting discitis.

Treatment for discitis involves hospital admission for intravenous antibiotics. Before starting the antibiotics, it is recommended to send three sets of blood cultures and a full set of blood tests, including a C-reactive protein (CRP) test, to the laboratory.

A typical antibiotic regimen for discitis would include intravenous flucloxacillin 2 g every 6 hours as the first-line treatment if there is no penicillin allergy. Intravenous vancomycin may be used if the infection was acquired in the hospital, if there is a high risk of methicillin-resistant Staphylococcus aureus (MRSA) infection, or if there is a documented penicillin allergy.

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.

Acute epiglottitis is a condition characterized by inflammation of the epiglottis. It can be life-threatening as it can completely block the airway, especially if not diagnosed promptly. In the past, the most common cause was Haemophilus influenzae type b (Hib), but with the widespread use of the Hib vaccine, it has become rare in children and is now more commonly seen in adults caused by Streptococcus spp like Streptococcus pyogenes and Streptococcus pneumonia. Other bacterial causes include Staphylococcus aureus, Pseudomonas spp, Moraxella catarrhalis, and Mycobacterium tuberculosis.

The typical symptoms of acute epiglottitis include fever, sore throat (initially resembling a viral sore throat), painful swallowing, difficulty swallowing secretions (seen as drooling in children), muffled voice (referred to as ‘hot potato’ voice), rapid heartbeat, tenderness in the front of the neck over the hyoid bone, cervical lymph node enlargement, and rapid deterioration in children.

To diagnose acute epiglottitis, the gold standard investigation is fibre-optic laryngoscopy, which allows direct visualization of the epiglottis. However, laryngoscopy should only be performed in settings prepared for intubation or tracheostomy in case upper airway obstruction occurs. If laryngoscopy is not possible, a lateral neck X-ray may be helpful, as it can show the characteristic ‘thumbprint sign’.

Management of acute epiglottitis usually involves conservative measures such as intravenous or oral antibiotics. However, in some cases, intubation may be necessary.

For adults and children over the age of 12 who are suspected to have glandular fever and have a normal immune system, it is recommended to conduct a Full Blood Count (FBC) and a monospot test during the second week of the illness. The timing and choice of investigations for glandular fever vary depending on the patient’s age, immune system status, and duration of symptoms. For children under the age of 12 and individuals with compromised immune systems, it is advised to perform a blood test for Epstein-Barr virus (EBV) viral serology after at least 7 days of illness. However, for immunocompetent adults and children older than 12, a FBC with differential white cell count and a monospot test (heterophile antibodies) should be conducted during the second week of the illness.

Further Reading:

Glandular fever, also known as infectious mononucleosis or mono, is a clinical syndrome characterized by symptoms such as sore throat, fever, and swollen lymph nodes. It is primarily caused by the Epstein-Barr virus (EBV), with other viruses and infections accounting for the remaining cases. Glandular fever is transmitted through infected saliva and primarily affects adolescents and young adults. The incubation period is 4-8 weeks.

The majority of EBV infections are asymptomatic, with over 95% of adults worldwide having evidence of prior infection. Clinical features of glandular fever include fever, sore throat, exudative tonsillitis, lymphadenopathy, and prodromal symptoms such as fatigue and headache. Splenomegaly (enlarged spleen) and hepatomegaly (enlarged liver) may also be present, and a non-pruritic macular rash can sometimes occur.

Glandular fever can lead to complications such as splenic rupture, which increases the risk of rupture in the spleen. Approximately 50% of splenic ruptures associated with glandular fever are spontaneous, while the other 50% follow trauma. Diagnosis of glandular fever involves various investigations, including viral serology for EBV, monospot test, and liver function tests. Additional serology tests may be conducted if EBV testing is negative.

Management of glandular fever involves supportive care and symptomatic relief with simple analgesia. Antiviral medication has not been shown to be beneficial. It is important to identify patients at risk of serious complications, such as airway obstruction, splenic rupture, and dehydration, and provide appropriate management. Patients can be advised to return to normal activities as soon as possible, avoiding heavy lifting and contact sports for the first month to reduce the risk of splenic rupture.

Rare but serious complications associated with glandular fever include hepatitis, upper airway obstruction, cardiac complications, renal complications, neurological complications, haematological complications, chronic fatigue, and an increased risk of lymphoproliferative cancers and multiple sclerosis.

The primary treatment for malignant hyperthermia is dantrolene. Dantrolene works by blocking the release of calcium through calcium channels, resulting in the relaxation of skeletal muscles.

Further Reading:

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

ACE inhibitors should not be used in individuals with HAE because they can enhance the effects of bradykinin. This can lead to drug-induced angioedema, which is a known side effect of ACE inhibitors. In individuals with HAE, ACE inhibitors can trigger attacks of angioedema.

Further Reading:

Angioedema and urticaria are related conditions that involve swelling in different layers of tissue. Angioedema refers to swelling in the deeper layers of tissue, such as the lips and eyelids, while urticaria, also known as hives, refers to swelling in the epidermal skin layers, resulting in raised red areas of skin with itching. These conditions often coexist and may have a common underlying cause.

Angioedema can be classified into allergic and non-allergic types. Allergic angioedema is the most common type and is usually triggered by an allergic reaction, such as to certain medications like penicillins and NSAIDs. Non-allergic angioedema has multiple subtypes and can be caused by factors such as certain medications, including ACE inhibitors, or underlying conditions like hereditary angioedema (HAE) or acquired angioedema.

HAE is an autosomal dominant disease characterized by a deficiency of C1 esterase inhibitor. It typically presents in childhood and can be inherited or acquired as a result of certain disorders like lymphoma or systemic lupus erythematosus. Acquired angioedema may have similar clinical features to HAE but is caused by acquired deficiencies of C1 esterase inhibitor due to autoimmune or lymphoproliferative disorders.

The management of urticaria and allergic angioedema focuses on ensuring the airway remains open and addressing any identifiable triggers. In mild cases without airway compromise, patients may be advised that symptoms will resolve without treatment. Non-sedating antihistamines can be used for up to 6 weeks to relieve symptoms. Severe cases of urticaria may require systemic corticosteroids in addition to antihistamines. In moderate to severe attacks of allergic angioedema, intramuscular epinephrine may be considered.

The management of HAE involves treating the underlying deficiency of C1 esterase inhibitor. This can be done through the administration of C1 esterase inhibitor, bradykinin receptor antagonists, or fresh frozen plasma transfusion, which contains C1 inhibitor.

In summary, angioedema and urticaria are related conditions involving swelling in different layers of tissue. They can coexist and may have a common underlying cause. Management involves addressing triggers, using antihistamines, and in severe cases, systemic corticosteroids or other specific treatments for HAE.

The fascia iliaca compartment is a space within the body that has specific boundaries. It is located at the front of the hip and is surrounded by various muscles and structures. The anterior limit of this compartment is formed by the posterior surface of the fascia iliaca, which covers the iliacus muscle. Additionally, the medial reflection of this fascia covers every surface of the psoas major muscle. On the posterior side, the limit is formed by the anterior surface of the iliacus muscle and the psoas major muscle. The medial boundary is the vertebral column, while the cranially lateral boundary is the inner lip of the iliac crest. This compartment is also continuous with the space between the quadratus lumborum muscle and its fascia in a cranio-medial direction.

The fascia iliaca compartment is important because it allows for the deposition of local anesthetic in sufficient volumes. This can be achieved through a straightforward injection, which targets the femoral and lateral femoral cutaneous nerves. These nerves supply sensation to the medial, anterior, and lateral thigh. Occasionally, the obturator nerve is also blocked, although this can vary from person to person.

To perform a fascia iliaca compartment block (FICB), specific landmarks need to be identified. An imaginary line is drawn between the anterior superior iliac spine (ASIS) and the pubic tubercle. This line is then divided into thirds. The injection entry point is marked 1 cm caudal (inferior) from the junction of the lateral and middle third.

However, there are certain contraindications to performing a FICB. These include patient refusal, anticoagulation or bleeding disorders, allergy to local anesthetics, previous femoral bypass surgery, and infection or inflammation over the injection site.

As with any medical procedure, there are potential complications associated with a FICB. These can include intravascular injection, local anesthetic toxicity, allergy to the local anesthetic, temporary or permanent nerve damage, infection, and block failure. It is important for healthcare professionals to be aware of these risks and take appropriate precautions when performing a FICB.

Septic arthritis occurs when an infectious agent invades a joint, causing it to become purulent. The main symptoms of septic arthritis include pain in the affected joint, redness, warmth, and swelling of the joint, and difficulty moving the joint. Patients may also experience fever and systemic upset. The most common cause of septic arthritis is Staphylococcus aureus, but other bacteria such as Streptococcus spp., Haemophilus influenzae, Neisseria gonorrhoea, and Escherichia coli can also be responsible.

According to the current recommendations by NICE and the BNF, the initial treatment for septic arthritis is flucloxacillin. However, if a patient is allergic to penicillin, clindamycin can be used instead. If there is a suspicion of MRSA infection, vancomycin is the recommended choice. In cases where gonococcal arthritis or a Gram-negative infection is suspected, cefotaxime is the preferred treatment. The suggested duration of treatment is typically 4-6 weeks, although it may be longer if the infection is complicated.

Hypothermia occurs when the core body temperature drops below 35°C. It is categorized as mild (32-35°C), moderate (28-32°C), or severe (<28°C). Rescuers at the scene can use the Swiss staging system to describe the condition of victims. The stages range from clearly conscious and shivering to unconscious and not breathing, with death due to irreversible hypothermia being the most severe stage. There are several risk factors for hypothermia, including environmental exposure, unsatisfactory housing, poverty, lack of cold awareness, drugs, alcohol, acute confusion, hypothyroidism, and sepsis. The clinical features of hypothermia vary depending on the severity. At 32-35°C, symptoms may include apathy, amnesia, ataxia, and dysarthria. At 30-32°C, there may be a decreased level of consciousness, hypotension, arrhythmias, respiratory depression, and muscular rigidity. Below 30°C, ventricular fibrillation may occur, especially with excessive movement or invasive procedures. Diagnosing hypothermia involves checking the core temperature using an oesophageal, rectal, or tympanic probe with a low reading thermometer. Rectal and tympanic temperatures may lag behind core temperature and are unreliable in hypothermia. Various investigations should be carried out, including blood tests, blood glucose, amylase, blood cultures, arterial blood gas, ECG, chest X-ray, and CT head if there is suspicion of head injury or CVA. The management of hypothermia involves supporting the ABCs, treating the patient in a warm room, removing wet clothes and drying the skin, monitoring the ECG, providing warmed, humidified oxygen, correcting hypoglycemia with IV glucose, and handling the patient gently to avoid VF arrest. Rewarming methods include passive Rewarming with warm blankets or Bair hugger/polythene sheets, surface Rewarming with a water bath, core Rewarming with heated, humidified oxygen or peritoneal lavage, and extracorporeal Rewarming via cardiopulmonary bypass for severe hypothermia/cardiac arrest. In the case of hypothermic cardiac arrest, CPR should be performed with chest compressions and ventilations at standard rates.

The risk of contracting meningococcal disease from a close contact is low. However, the risk is highest within the first seven days after the disease is diagnosed and decreases significantly afterwards.

Prophylaxis or vaccination for close contacts is typically organized by secondary care. It is recommended for the following individuals, regardless of their meningococcal vaccination status:

– People who have had prolonged close contact with the infected person in a household-type setting during the seven days prior to the onset of illness. This includes individuals living or sleeping in the same household, students in the same dormitory, partners, or university students sharing a kitchen in a hall of residence.

– People who have had brief close contact with the infected person, but only if they have been directly exposed to large particle droplets or secretions from the respiratory tract of the case around the time of admission to the hospital.

Antibiotic prophylaxis should be administered as soon as possible, ideally within 24 hours after the diagnosis of the index case.

Post-exposure prophylaxis is recommended for healthcare staff who have been exposed to direct nasopharyngeal secretions (without wearing a mask or personal protective equipment) from a known or highly probable case. This includes situations such as mouth-to-mouth resuscitation, airway management (suction/intubation), or prolonged close care within 1 meter of the patient who has been coughing or sneezing droplet secretions.

For more information, you can refer to the NICE Clinical Knowledge Summary on the management of close contacts of patients with meningococcal disease.

The size of the cannula used for IV fluid infusion determines the maximum flow rate. For a 20g cannula, the maximum flow rate is around 60 ml per minute. As a result, the fastest infusion time through a 20g cannula is approximately 15 minutes for a maximum volume of 1000 ml.

Further Reading:

Peripheral venous cannulation is a procedure that should be performed following established guidelines to minimize the risk of infection, injury, extravasation, and early failure of the cannula. It is important to maintain good hand hygiene, use personal protective equipment, ensure sharps safety, and employ an aseptic non-touch technique during the procedure.

According to the National Institute for Health and Care Excellence (NICE), the skin should be disinfected with a solution of 2% chlorhexidine gluconate and 70% alcohol before inserting the catheter. It is crucial to allow the disinfectant to completely dry before inserting the cannula.

The flow rates of IV cannulas can vary depending on factors such as the gauge, color, type of fluid used, presence of a bio-connector, length of the cannula, and whether the fluid is drained under gravity or pumped under pressure. However, the following are typical flow rates for different gauge sizes: 14 gauge (orange) has a flow rate of 270 ml/minute, 16 gauge (grey) has a flow rate of 180 ml/minute, 18 gauge (green) has a flow rate of 90 ml/minute, 20 gauge (pink) has a flow rate of 60 ml/minute, and 22 gauge (blue) has a flow rate of 36 ml/minute. These flow rates are based on infusing 1000 ml of normal saline under ideal circumstances, but they may vary in practice.

The recommended target SpO2, which measures the percentage of oxygen saturation in the blood, following a cardiac arrest is 94-98%. This range ensures that the patient receives adequate oxygenation without the risk of hyperoxia, which is an excess of oxygen in the body.

Further Reading:

Cardiopulmonary arrest is a serious event with low survival rates. In non-traumatic cardiac arrest, only about 20% of patients who arrest as an in-patient survive to hospital discharge, while the survival rate for out-of-hospital cardiac arrest is approximately 8%. The Resus Council BLS/AED Algorithm for 2015 recommends chest compressions at a rate of 100-120 per minute with a compression depth of 5-6 cm. The ratio of chest compressions to rescue breaths is 30:2.

After a cardiac arrest, the goal of patient care is to minimize the impact of post cardiac arrest syndrome, which includes brain injury, myocardial dysfunction, the ischaemic/reperfusion response, and the underlying pathology that caused the arrest. The ABCDE approach is used for clinical assessment and general management. Intubation may be necessary if the airway cannot be maintained by simple measures or if it is immediately threatened. Controlled ventilation is aimed at maintaining oxygen saturation levels between 94-98% and normocarbia. Fluid status may be difficult to judge, but a target mean arterial pressure (MAP) between 65 and 100 mmHg is recommended. Inotropes may be administered to maintain blood pressure. Sedation should be adequate to gain control of ventilation, and short-acting sedating agents like propofol are preferred. Blood glucose levels should be maintained below 8 mmol/l. Pyrexia should be avoided, and there is some evidence for controlled mild hypothermia but no consensus on this.

Post ROSC investigations may include a chest X-ray, ECG monitoring, serial potassium and lactate measurements, and other imaging modalities like ultrasonography, echocardiography, CTPA, and CT head, depending on availability and skills in the local department. Treatment should be directed towards the underlying cause, and PCI or thrombolysis may be considered for acute coronary syndrome or suspected pulmonary embolism, respectively.

Patients who are comatose after ROSC without significant pre-arrest comorbidities should be transferred to the ICU for supportive care. Neurological outcome at 72 hours is the best prognostic indicator of outcome.

The diving reflex occurs when the face comes into contact with cold water, leading to apnoea, bradycardia, and peripheral vasoconstriction. This response helps decrease the workload on the heart, lower oxygen demand in the heart muscle, and ensure adequate blood flow to the brain and vital organs. The trigeminal nerve (CN V) is responsible for transmitting sensory information, while the vagus nerve (CN X) primarily controls the motor response. This reflex is more prominent in young children and is believed to contribute to their improved survival rates in prolonged submersion in cold water.

Further Reading:

Drowning is the process of experiencing respiratory impairment from submersion or immersion in liquid. It can be classified as cold-water or warm-water drowning. Risk factors for drowning include young age and male sex. Drowning impairs lung function and gas exchange, leading to hypoxemia and acidosis. It also causes cardiovascular instability, which contributes to metabolic acidosis and cell death.

When someone is submerged or immersed, they will voluntarily hold their breath to prevent aspiration of water. However, continued breath holding causes progressive hypoxia and hypercapnia, leading to acidosis. Eventually, the respiratory center sends signals to the respiratory muscles, forcing the individual to take an involuntary breath and allowing water to be aspirated into the lungs. Water entering the lungs stimulates a reflex laryngospasm that prevents further penetration of water. Aspirated water can cause significant hypoxia and damage to the alveoli, leading to acute respiratory distress syndrome (ARDS).

Complications of drowning include cardiac ischemia and infarction, infection with waterborne pathogens, hypothermia, neurological damage, rhabdomyolysis, acute tubular necrosis, and disseminated intravascular coagulation (DIC).

In children, the diving reflex helps reduce hypoxic injury during submersion. It causes apnea, bradycardia, and peripheral vasoconstriction, reducing cardiac output and myocardial oxygen demand while maintaining perfusion of the brain and vital organs.

Associated injuries with drowning include head and cervical spine injuries in patients rescued from shallow water. Investigations for drowning include arterial blood gases, chest X-ray, ECG and cardiac monitoring, core temperature measurement, and blood and sputum cultures if secondary infection is suspected.

Management of drowning involves extricating the patient from water in a horizontal position with spinal precautions if possible. Cardiovascular considerations should be taken into account when removing patients from water to prevent hypotension and circulatory collapse. Airway management, supplemental oxygen, and ventilation strategies are important in maintaining oxygenation and preventing further lung injury. Correcting hypotension, electrolyte disturbances, and hypothermia is also necessary. Attempting to drain water from the lungs is ineffective.

Patients without associated physical injury who are asymptomatic and have no evidence of respiratory compromise after six hours can be safely discharged home. Ventilation strategies aim to maintain oxygenation while minimizing ventilator-associated lung injury.

The Manchester Mandibular Fracture Decision Rule consists of five signs that indicate a possible mandibular fracture: malocclusion, trismus, pain with mouth closed, broken teeth, and step deformity. If none of these signs are present, it is unlikely that a mandibular fracture has occurred. However, if one or more of these signs are present, it is recommended to obtain an X-ray for further evaluation. It is important to note that gum lacerations, although commonly seen in mandibular fractures, are not included in the Manchester Mandibular Fracture Decision Rule.

Further Reading:

Mandibular fractures are a common type of facial fracture that often present to the emergency department. The mandible, or lower jaw, is formed by the fusion of two hemimandibles and articulates with the temporomandibular joints. Fractures of the mandible are typically caused by direct lateral force and often involve multiple fracture sites, including the body, condylar head and neck, and ramus.

When assessing for mandibular fractures, clinicians should use a look, feel, move method similar to musculoskeletal examination. However, it is important to note that TMJ effusion, muscle spasm, and pain can make moving the mandible difficult. Key signs of mandibular fracture include malocclusion, trismus (limited mouth opening), pain with the mouth closed, broken teeth, step deformity, hematoma in the sublingual space, lacerations to the gum mucosa, and bleeding from the ear.

The Manchester Mandibular Fracture Decision Rule uses the absence of five exam findings (malocclusion, trismus, broken teeth, pain with closed mouth, and step deformity) to exclude mandibular fracture. This rule has been found to be 100% sensitive and 39% specific in detecting mandibular fractures. Imaging is an important tool in diagnosing mandibular fractures, with an OPG X-ray considered the best initial imaging for TMJ dislocation and mandibular fracture. CT may be used if the OPG is technically difficult or if a CT is being performed for other reasons, such as a head injury.

It is important to note that head injury often accompanies mandibular fractures, so a thorough head injury assessment should be performed. Additionally, about a quarter of patients with mandibular fractures will also have a fracture of at least one other facial bone.

Retinal detachment is a condition where the retina separates from the retinal pigment epithelium, resulting in a fluid-filled space between them. This case presents a classic description of retinal detachment. Several risk factors increase the likelihood of developing this condition, including myopia, being male, having a family history of retinal detachment, previous episodes of retinal detachment, blunt ocular trauma, previous cataract surgery, diabetes mellitus (especially if proliferative retinopathy is present), glaucoma, and cataracts.

The clinical features commonly associated with retinal detachment include flashes of light, particularly at the edges of vision (known as photopsia), a dense shadow in the peripheral vision that spreads towards the center, a sensation of a curtain drawing across the eye, and central visual loss. Fundoscopy, a procedure to examine the back of the eye, reveals a sheet of sensory retina billowing towards the center of the eye. Additionally, a positive Amsler grid test, where straight lines appear curved or wavy, may indicate retinal detachment.

Other possible causes of floaters include posterior vitreous detachment, retinal tears, vitreous hemorrhage, and migraine with aura. However, in this case, the retinal appearance described is consistent with retinal detachment.

It is crucial to arrange an urgent same-day ophthalmology referral for this patient. Fortunately, approximately 90% of retinal detachments can be successfully repaired with one operation, and an additional 6% can be salvaged with subsequent procedures. If the retina remains fixed six months after surgery, the likelihood of it becoming detached again is low.

In cases of penetrating abdominal trauma, two organs that are frequently affected are the liver and the small bowel. This means that when a person sustains a stab wound or any other type of injury that penetrates the abdomen, these two organs are at a higher risk of being damaged.

Further Reading:

Abdominal trauma can be classified into two categories: blunt trauma and penetrating trauma. Blunt trauma occurs when compressive or deceleration forces are applied to the abdomen, often resulting from road traffic accidents or direct blows during sports. The spleen and liver are the organs most commonly injured in blunt abdominal trauma. On the other hand, penetrating trauma involves injuries that pierce the skin and enter the abdominal cavity, such as stabbings, gunshot wounds, or industrial accidents. The bowel and liver are the organs most commonly affected in penetrating injuries.

When it comes to imaging in blunt abdominal trauma, there are three main modalities that are commonly used: focused assessment with sonography in trauma (FAST), diagnostic peritoneal lavage (DPL), and computed tomography (CT). FAST is a non-invasive and quick method used to detect free intraperitoneal fluid, aiding in the decision on whether a laparotomy is needed. DPL is also used to detect intraperitoneal blood and can be used in both unstable blunt abdominal trauma and penetrating abdominal trauma. However, it is more invasive and time-consuming compared to FAST and has largely been replaced by it. CT, on the other hand, is the gold standard for diagnosing intra-abdominal pathology and is used in stable abdominal trauma patients. It offers high sensitivity and specificity but requires a stable and cooperative patient. It also involves radiation and may have delays in availability.

In the case of penetrating trauma, it is important to assess these injuries with the help of a surgical team. Penetrating objects should not be removed in the emergency department as they may be tamponading underlying vessels. Ideally, these injuries should be explored in the operating theater.

In summary, abdominal trauma can be classified into blunt trauma and penetrating trauma. Blunt trauma is caused by compressive or deceleration forces and commonly affects the spleen and liver. Penetrating trauma involves injuries that pierce the skin and commonly affect the bowel and liver. Imaging modalities such as FAST, DPL, and CT are used to assess and diagnose abdominal trauma, with CT being the gold standard. Penetrating injuries should be assessed by a surgical team and should ideally be explored in the operating theater.

When administering treatment to patients with hepatic impairment, it is crucial to consider that midazolam is metabolized in the liver.

Further Reading:

Procedural sedation is commonly used by emergency department (ED) doctors to minimize pain and discomfort during procedures that may be painful or distressing for patients. Effective procedural sedation requires the administration of analgesia, anxiolysis, sedation, and amnesia. This is typically achieved through the use of a combination of short-acting analgesics and sedatives.

There are different levels of sedation, ranging from minimal sedation (anxiolysis) to general anesthesia. It is important for clinicians to understand the level of sedation being used and to be able to manage any unintended deeper levels of sedation that may occur. Deeper levels of sedation are similar to general anesthesia and require the same level of care and monitoring.

Various drugs can be used for procedural sedation, including propofol, midazolam, ketamine, and fentanyl. Each of these drugs has its own mechanism of action and side effects. Propofol is commonly used for sedation, amnesia, and induction and maintenance of general anesthesia. Midazolam is a benzodiazepine that enhances the effect of GABA on the GABA A receptors. Ketamine is an NMDA receptor antagonist and is used for dissociative sedation. Fentanyl is a highly potent opioid used for analgesia and sedation.

The doses of these drugs for procedural sedation in the ED vary depending on the drug and the route of administration. It is important for clinicians to be familiar with the appropriate doses and onset and peak effect times for each drug.

Safe sedation requires certain requirements, including appropriate staffing levels, competencies of the sedating practitioner, location and facilities, and monitoring. The level of sedation being used determines the specific requirements for safe sedation.

After the procedure, patients should be monitored until they meet the criteria for safe discharge. This includes returning to their baseline level of consciousness, having vital signs within normal limits, and not experiencing compromised respiratory status. Pain and discomfort should also be addressed before discharge.

The intravascular volume of an infant is approximately 80 ml/kg. In older children, the intravascular volume is around 70 ml/kg.

Dehydration itself does not lead to death, but shock can. Shock can occur when there is a loss of 20 ml/kg from the intravascular space, while clinical dehydration is only noticeable after total losses of more than 25 ml/kg.

The maintenance fluid requirements for healthy, typical children are summarized in the table below:

Bodyweight:
– First 10 kg: Daily fluid requirement of 100 ml/kg, hourly fluid requirement of 4 ml/kg
– Second 10 kg: Daily fluid requirement of 50 ml/kg, hourly fluid requirement of 2 ml/kg
– Subsequent kg: Daily fluid requirement of 20 ml/kg, hourly fluid requirement of 1 ml/kg

Therefore, this child’s daily maintenance fluid requirement can be calculated as follows:

– First 10 kg: 100 ml/kg = 1000 ml
– Second 10 kg: 50 ml/kg = 500 ml
– Subsequent kg: 20 ml/kg = 40 ml

Total daily maintenance fluid requirement: 1540 ml

The Arthus reaction is a response that occurs when antigen/antibody complexes are formed in the skin after an antigen is injected. Although rare, these reactions can happen after receiving vaccines that contain tetanus toxoid or diphtheria toxoid. They are classified as a type III hypersensitivity reaction.

Arthus reactions are characterized by pain, swelling, induration, hemorrhage, and sometimes necrosis. Typically, these symptoms appear 4-12 hours after vaccination.

Type III hypersensitivity reactions occur when insoluble antigen-antibody complexes accumulate in different tissues and are not effectively cleared by the body’s innate immune cells. This leads to an inflammatory response in the affected tissues.

Some other examples of type III hypersensitivity reactions include immune complex glomerulonephritis, rheumatoid arthritis, systemic lupus erythematosus, serum sickness, and extrinsic allergic alveolitis.

In a patient with chronic hepatitis B, the typical serology results would show positive anti-HBc and positive HBsAg. This indicates that the patient has a long-term infection with hepatitis B. The presence of IgG anti-HBc indicates that the infection will persist for life, while IgM anti-HBc will only be present for about 6 months.

If a patient has positive anti-HBs but all other serological markers are negative, it suggests that they have been previously immunized against hepatitis B. On the other hand, if a patient has positive anti-HBs along with positive anti-HBc, it indicates that they have developed immunity following a past infection.

In the case of an acute hepatitis B infection that has been cleared more than 6 months ago, the serology results would typically show positive anti-HBc but negative HBsAg. This indicates that the infection has been successfully cleared by the immune system.

Further Reading:

Hepatitis B is a viral infection that is transmitted through exposure to infected blood or body fluids. It can also be passed from mother to child during childbirth. The incubation period for hepatitis B is typically 6-20 weeks. Common symptoms of hepatitis B include fever, jaundice, and elevated liver transaminases.

Complications of hepatitis B infection can include chronic hepatitis, which occurs in 5-10% of cases, fulminant liver failure, hepatocellular carcinoma, glomerulonephritis, polyarteritis nodosa, and cryoglobulinemia.

Immunization against hepatitis B is recommended for various at-risk groups, including healthcare workers, intravenous drug users, sex workers, close family contacts of infected individuals, and those with chronic liver disease or kidney disease. The vaccine contains HBsAg adsorbed onto an aluminum hydroxide adjuvant and is prepared using recombinant DNA technology. Most vaccination schedules involve three doses of the vaccine, with a booster recommended after 5 years.

Around 10-15% of adults may not respond adequately to the vaccine. Risk factors for poor response include age over 40, obesity, smoking, alcohol excess, and immunosuppression. Testing for anti-HBs levels is recommended for healthcare workers and patients with chronic kidney disease. Interpretation of anti-HBs levels can help determine the need for further vaccination or testing for infection.

In terms of serology, the presence of HBsAg indicates acute disease if present for 1-6 months, and chronic disease if present for more than 6 months. Anti-HBs indicates immunity, either through exposure or immunization. Anti-HBc indicates previous or current infection, with IgM anti-HBc appearing during acute or recent infection and IgG anti-HBc persisting. HbeAg is a marker of infectivity.

Management of hepatitis B involves notifying the Health Protection Unit for surveillance and contact tracing. Patients should be advised to avoid alcohol and take precautions to minimize transmission to partners and contacts. Referral to a gastroenterologist or hepatologist is recommended for all patients. Symptoms such as pain, nausea, and itch can be managed with appropriate drug treatment. Pegylated interferon-alpha and other antiviral medications like tenofovir and entecavir may be used to suppress viral replication in chronic carriers.