The nerve agents, also known as nerve gases, are a group of highly toxic chemical warfare agents that were initially developed just before and during World War II.

The first compounds to be created are referred to as the G agents (with G representing German, as they were discovered and synthesized by German scientists). These include Tabun (GA), Sarin (GB), and Soman (GD).

In the 1950s, the V agents (with V standing for venomous) were synthesized, and they are approximately 10 times more poisonous than sarin. These include Venomous agent X (VX), Venomous agent E (VE), Venomous agent G (VG), and Venomous agent M (VM).

One of the most well-known incidents involving the use of a nerve agent was the March 1995 Tokyo subway sarin attack. During this attack, Sarin was released into the Tokyo subway system during rush hour. As a result, over 5,000 people sought medical attention. Among them, 984 were moderately poisoned, 54 were severely poisoned, and 12 lost their lives.

The nerve agents are organophosphorus esters that are chemically related to organophosphorus insecticides. They work by inhibiting acetylcholinesterase (AChE), an enzyme that breaks down the neurotransmitter acetylcholine (ACh). This leads to an accumulation of ACh at both muscarinic and nicotinic cholinergic receptors.

Nerve agents can be absorbed through any body surface. When dispersed as a spray or aerosol, they can be absorbed through the skin, eyes, and respiratory tract. When dispersed as a vapor, they are primarily absorbed through the respiratory tract and eyes. If a sufficient amount of agent is absorbed, local effects are followed by generalized systemic effects.

Aminoglycosides have the ability to pass through the placenta and can lead to damage to the 8th cranial nerve in the fetus, resulting in permanent bilateral deafness.

ACE inhibitors, such as ramipril, can cause hypoperfusion, renal failure, and the oligohydramnios sequence if given in the 2nd and 3rd trimesters.

Aminoglycosides, like gentamicin, can cause ototoxicity and deafness in the fetus.

High doses of aspirin can lead to 1st 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, including diazepam, when administered late in pregnancy, can result in respiratory depression and a neonatal withdrawal syndrome.

Calcium-channel blockers, if given in the 1st trimester, can cause phalangeal abnormalities. If given in the 2nd and 3rd trimesters, they can lead to fetal growth retardation.

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

Chloramphenicol is associated with grey baby syndrome.

Corticosteroids, if given in the 1st trimester, may cause orofacial clefts.

Danazol, if given in the 1st trimester, can cause masculinization of the female fetuses genitals.

Finasteride should not be handled by pregnant women as crushed or broken tablets can be absorbed through the skin and affect male sex organ development.

Haloperidol, if given in the 1st trimester, may cause limb malformations. If given in the 3rd trimester, there is an increased risk of extrapyramidal symptoms in the neonate.

Heparin can lead to maternal bleeding and thrombocytopenia.

Isoniazid can cause maternal liver damage and neuropathy and seizures in the neonate.

Isotretinoin carries a high risk of teratogenicity, including multiple congenital malformations, spontaneous abortion, and intellectual disability.

Lithium, if given in the 1st trimester, poses a risk of fetal cardiac malformations.

The term Apparent Life-Threatening Event (ALTE) has traditionally been used to describe a specific type of event. However, in 2016, the American Academy of Paediatrics (AAP) recommended replacing this term with a new one called Brief Resolved Unexplained Event (BRUE).

An ALTE is defined as an episode that is frightening to the observer and is characterized by a combination of symptoms such as apnoea (central or occasionally obstructive), color change (usually cyanotic or pallid but occasionally erythematous or plethoric), significant change in muscle tone (usually marked limpness), choking, or gagging. In some cases, the observer may even fear that the infant has died.

On the other hand, BRUE has stricter criteria and is only applicable to episodes that occur in infants under 12 months old. A BRUE is considered brief, typically lasting 2-30 seconds but no longer than 1 minute. It must also have resolved, meaning the infant has returned to their baseline state. Additionally, it should not be explained by any identifiable medical condition and must be characterized by at least one of the following: cyanosis or pallor, absent, decreased, or irregular breathing, marked change in muscle tone (hyper- or hypotonia), or altered level of responsiveness.

To diagnose a BRUE, a full history and physical examination of the infant must be conducted, and if no explanation for the event is found, it can be classified as a BRUE. Once a BRUE is diagnosed, it can be risk-stratified to guide further management.

A BRUE is considered low risk if the infant has fully recovered, there are no concerning history or physical examination findings, and the following criteria are met: the infant is over 60 days old, born after 32 weeks gestation with a corrected gestational age over 45 weeks, no CPR was performed by a trained healthcare professional, and this was the first event that lasted less than 1 minute.

Low-risk infants can be safely discharged with early outpatient follow-up within 24 hours. However, it is important to involve the parents/caregivers in the decision-making process. They should be informed that a low-risk BRUE is unlikely to indicate a severe underlying disorder and that the event is unlikely to happen again.

Before discharge, it may be advisable to perform an ECG, observe the infant for a brief period, and conduct a pertussis swab

Shenton’s line is a useful tool for identifying hip fractures on radiographs. It is a curved line that is drawn along the bottom edge of the upper pubic bone and the inner lower edge of the femur neck. This line should be smooth and uninterrupted. If there are any breaks or irregularities in the line, it could indicate a fracture, dysplasia, or dislocation.

Further Reading:

Fractured neck of femur is a common injury, especially in elderly patients who have experienced a low impact fall. Risk factors for this type of fracture include falls, osteoporosis, and other bone disorders such as metastatic cancers, hyperparathyroidism, and osteomalacia.

There are different classification systems for hip fractures, but the most important differentiation is between intracapsular and extracapsular fractures. The blood supply to the femoral neck and head is primarily from ascending cervical branches that arise from an arterial anastomosis between the medial and lateral circumflex branches of the femoral arteries. Fractures in the intracapsular region can damage the blood supply and lead to avascular necrosis (AVN), with the risk increasing with displacement. The Garden classification can be used to classify intracapsular neck of femur fractures and determine the risk of AVN. Those at highest risk will typically require hip replacement or arthroplasty.

Fractures below or distal to the capsule are termed extracapsular and can be further described as intertrochanteric or subtrochanteric depending on their location. The blood supply to the femoral neck and head is usually maintained with these fractures, making them amenable to surgery that preserves the femoral head and neck, such as dynamic hip screw fixation.

Diagnosing hip fractures can be done through radiographs, with Shenton’s line and assessing the trabecular pattern of the proximal femur being helpful techniques. X-rays should be obtained in both the AP and lateral views, and if an occult fracture is suspected, an MRI or CT scan may be necessary.

In terms of standards of care, it is important to assess the patient’s pain score within 15 minutes of arrival in the emergency department and provide appropriate analgesia within the recommended timeframes. Patients with moderate or severe pain should have their pain reassessed within 30 minutes of receiving analgesia. X-rays should be obtained within 120 minutes of arrival, and patients should be admitted within 4 hours of arrival.

Gallstone ileus occurs when a gallstone becomes stuck in the small intestine, specifically at the caeco-ileal valve. This condition presents with similar symptoms to other causes of small bowel obstruction. Patients may experience colicky central abdominal pain, which can have a gradual onset. Vomiting is common and tends to occur earlier in the course of the illness compared to large bowel obstruction. Abdominal distension and the absence of flatus are also typical signs. Additionally, there may be a lack of normal bowel sounds or the presence of high-pitched tinkling sounds. A mass in the right upper quadrant of the abdomen may be palpable.

The initial noticeable abnormality in sensory testing for diabetic neuropathy is often the loss of vibration sense. Reduced sensation, particularly in vibration sense, is typically the first symptom to be observed in diabetic neuropathy.

Further Reading:

Diabetic foot is a complication that can occur in individuals with diabetes due to long-standing high blood sugar levels. This leads to a process called glycation or glycosylation, where glucose binds to proteins and lipids in the body. Abnormal protein glycation can cause cellular dysfunction and various complications.

One of the main problems in diabetic foot is peripheral vascular disease and peripheral neuropathy. These conditions can result in significant foot issues, as trauma to the feet may go unnoticed and untreated. Vascular disease also impairs wound healing and increases the risk of developing ulcers.

Clinical features of diabetic foot include reduced sensation, especially to vibration, non-dermatomal sensory loss, foot deformities such as pes cavus and claw toes, and weak or absent foot pulses. It is important for diabetic patients to have their feet assessed regularly, at least annually, to identify any potential problems. Additional foot assessments should also be conducted during hospital admissions.

During a diabetic foot assessment, the healthcare provider should remove shoes, socks, and any bandages or dressings to examine both feet. They should assess for neuropathy using a 10 g monofilament to test foot sensation and check for limb ischemia by examining pulses and performing ankle brachial pressure index (ABPI) measurements. Any abnormal tissue, such as ulcers, calluses, infections, inflammation, deformities, or gangrene, should be documented. The risk of Charcot arthropathy should also be assessed.

The severity of foot ulcers in diabetic patients can be documented using standardized systems such as SINBAD or the University of Texas classification. The presence and severity of diabetic foot infection can be determined based on criteria such as local swelling, induration, erythema, tenderness, pain, warmth, and purulent discharge.

Management of foot ulcers involves offloading, control of foot infection, control of ischemia, wound debridement, and appropriate wound dressings. Antibiotics may be necessary depending on the severity of the infection. Diabetic patients with foot ulcers should undergo initial investigations including blood tests, wound swabs, and imaging to assess for possible osteomyelitis.

Charcot foot is a serious complication of diabetic peripheral neuropathy that results in progressive destructive arthropathy and foot deformity. Signs of Charcot foot include redness, swelling, warm skin, pain, and deformity. The hallmark deformity is midfoot collapse, known as the rocker-bottom foot.

In infants who are less than 4 weeks old, it is recommended to measure their body temperature using an electronic thermometer placed in the armpit.

For children between the ages of 4 weeks and 5 years, there are several methods that can be used to measure body temperature. These include using an electronic thermometer in the armpit, a chemical dot thermometer in the armpit, or an infra-red tympanic thermometer.

It is important to note that measuring temperature orally or rectally should be avoided in this age group. Additionally, forehead chemical thermometers are not reliable and should not be used.

This patient presents with elevated transaminases and gamma GT, along with mildly elevated ALP and hyperbilirubinemia. These findings strongly indicate a diagnosis of alcohol-induced hepatitis. Additionally, the patient’s history and examination features strongly suggest a history of chronic alcohol abuse and withdrawal, further supporting this diagnosis.

For the treatment of pregnant women with lower urinary tract infections (UTIs), it is recommended to provide them with an immediate prescription for antibiotics. It is important to consider their previous urine culture and susceptibility results, as well as any prior use of antibiotics that may have contributed to the development of resistant bacteria. Before starting antibiotics, it is advised to obtain a midstream urine sample from pregnant women and send it for culture and susceptibility testing.

Once the microbiological results are available, it is necessary to review the choice of antibiotic. If the bacteria are found to be resistant, it is recommended to switch to a narrow-spectrum antibiotic whenever possible. The choice of antibiotics for pregnant women aged 12 years and over is summarized below:

First-choice:
– Nitrofurantoin 100 mg modified-release taken orally twice daily for 3 days, if the estimated glomerular filtration rate (eGFR) is above 45 ml/minute.

Second-choice (if there is no improvement in lower UTI symptoms with the first-choice antibiotic for at least 48 hours, or if the first-choice is not suitable):
– Amoxicillin 500 mg taken orally three times daily for 7 days (only if culture results are available and show susceptibility).
– Cefalexin 500 mg taken twice daily for 7 days.

For alternative second-choice antibiotics, it is recommended to consult a local microbiologist and choose the appropriate antibiotics based on the culture and sensitivity results.

Adenosine is given through a rapid IV bolus, followed by a flush of saline solution. In adults, the starting dose is 6 mg, and if needed, an additional dose of 12 mg is given. If necessary, another dose of either 12 mg or 18 mg can be administered at intervals of 1-2 minutes until the desired effect is observed.

It is important to note that the latest ALS guidelines recommend an 18 mg dose for the third administration, while the BNF/NICE guidelines suggest a 12 mg dose.

However, patients who have undergone a heart transplant are particularly sensitive to the effects of adenosine. Therefore, their initial dose should be reduced to 3 mg, followed by 6 mg, and then 12 mg.