Anaemia can be categorized based on the size of red blood cells. Microcytic anaemia, characterized by a mean corpuscular volume (MCV) of less than 80 fl, can be caused by various factors such as iron deficiency, thalassaemia, anaemia of chronic disease (which can also be normocytic), sideroblastic anaemia (which can also be normocytic), lead poisoning, and aluminium toxicity (although this is now rare and mainly affects haemodialysis patients).

On the other hand, normocytic anaemia, with an MCV ranging from 80 to 100 fl, can be attributed to conditions like haemolysis, acute haemorrhage, bone marrow failure, anaemia of chronic disease (which can also be microcytic), mixed iron and folate deficiency, pregnancy, chronic renal failure, and sickle-cell disease.

Lastly, macrocytic anaemia, characterized by an MCV greater than 100 fl, can be caused by factors such as B12 deficiency, folate deficiency, hypothyroidism, reticulocytosis, liver disease, alcohol abuse, myeloproliferative disease, myelodysplastic disease, and certain drugs like methotrexate, hydroxyurea, and azathioprine.

It is important to understand the different causes of anaemia based on red cell size as this knowledge can aid in the diagnosis and management of this condition.

Le Fort fractures are complex fractures of the midface that involve the maxillary bone and surrounding structures. These fractures can occur in a horizontal, pyramidal, or transverse direction. The distinguishing feature of Le Fort fractures is the traumatic separation of the pterygomaxillary region. They make up approximately 10% to 20% of all facial fractures and can have severe consequences, both in terms of potential life-threatening injuries and disfigurement.

The Le Fort classification system categorizes midface fractures into three groups based on the plane of injury. As the classification level increases, the location of the maxillary fracture moves from inferior to superior within the maxilla.

Le Fort I fractures are horizontal fractures that occur across the lower aspect of the maxilla. These fractures cause the teeth to separate from the upper face and extend through the lower nasal septum, the lateral wall of the maxillary sinus, and into the palatine bones and pterygoid plates. They are sometimes referred to as a floating palate because they often result in the mobility of the hard palate from the midface. Common accompanying symptoms include facial swelling, loose teeth, dental fractures, and misalignment of the teeth.

Le Fort II fractures are pyramidal-shaped fractures, with the base of the pyramid located at the level of the teeth and the apex at the nasofrontal suture. The fracture line extends from the nasal bridge and passes through the superior wall of the maxilla, the lacrimal bones, the inferior orbital floor and rim, and the anterior wall of the maxillary sinus. These fractures are sometimes called a floating maxilla because they typically result in the mobility of the maxilla from the midface. Common symptoms include facial swelling, nosebleeds, subconjunctival hemorrhage, cerebrospinal fluid leakage from the nose, and widening and flattening of the nasal bridge.

Le Fort III fractures are transverse fractures of the midface. The fracture line passes through the nasofrontal suture, the maxillo frontal suture, the orbital wall, and the zygomatic arch and zygomaticofrontal suture. These fractures cause separation of all facial bones from the cranial base, earning them the nickname craniofacial disjunction or floating face fractures. They are the rarest and most severe type of Le Fort fracture. Common symptoms include significant facial swelling, bruising around the eyes, facial flattening, and the entire face can be shifted.

Jet ventilation through a needle cricothyroidotomy typically involves using a 1 bar (100 Kpa) oxygen source.

Further Reading:

Cricothyroidotomy, also known as cricothyrotomy, is a procedure used to create an airway by making an incision between the thyroid and cricoid cartilages. This can be done surgically with a scalpel or using a needle method. It is typically used as a short-term solution for establishing an airway in emergency situations where traditional intubation is not possible.

The surgical technique involves dividing the cricothyroid membrane transversely, while some recommend making a longitudinal skin incision first to identify the structures below. Complications of this procedure can include bleeding, infection, incorrect placement resulting in a false passage, fistula formation, cartilage fracture, subcutaneous emphysema, scarring leading to stenosis, and injury to the vocal cords or larynx. There is also a risk of damage to the recurrent laryngeal nerve, and failure to perform the procedure successfully can lead to hypoxia and death.

There are certain contraindications to surgical cricothyroidotomy, such as the availability of less invasive airway securing methods, patients under 12 years old (although a needle technique may be used), laryngeal fracture, pre-existing or acute laryngeal pathology, tracheal transection with retraction into the mediastinum, and obscured anatomical landmarks.

The needle (cannula) cricothyroidotomy involves inserting a cannula through the cricothyroid membrane to access the trachea. This method is mainly used in children in scenarios where ENT assistance is not available. However, there are drawbacks to this approach, including the need for high-pressure oxygen delivery, which can risk barotrauma and may not always be readily available. The cannula is also prone to kinking and displacement, and there is limited evacuation of expiratory gases, making it suitable for only a short period of time before CO2 retention becomes problematic.

In children, the cannula cricothyroidotomy and ventilation procedure involves extending the neck and stabilizing the larynx, inserting a 14g or 16g cannula at a 45-degree angle aiming caudally, confirming the position by aspirating air through a saline-filled syringe, and connecting it to an insufflation device or following specific oxygen pressure and flow settings for jet ventilation.

If a longer-term airway is needed, a cricothyroidotomy may be converted to

The intravascular volume of an infant is approximately 80 ml/kg, while in older children it is around 70 ml/kg. Dehydration itself does not lead to death, but shock can occur when there is a loss of 20 ml/kg from the intravascular space. Clinical dehydration becomes evident only after total losses greater than 25 ml/kg.

The table below summarizes the maintenance fluid requirements for well, normal children: Bodyweight:

– First 10 kg: Daily fluid requirement of 100 ml/kg and hourly fluid requirement of 4 ml/kg.

– Second 10 kg: Daily fluid requirement of 50 ml/kg and hourly fluid requirement of 2 ml/kg.

– Subsequent kg: Daily fluid requirement of 20 ml/kg and hourly fluid requirement of 1 ml/kg.

Based on this information, the hourly maintenance fluid requirements for this child can be calculated as follows:

– First 10 kg: 4 ml/kg = 40 ml

– Second 10 kg: 2 ml/kg = 20 ml

– Subsequent kg: 1 ml/kg = 5 ml

Therefore, the total hourly maintenance fluid requirement for this child is 65 ml.

This patient is experiencing a condition called acute alveolar osteitis, commonly known as ‘dry socket’. It occurs when the blood clot covering the socket gets dislodged, leaving the bone and nerve exposed. This can result in infection and intense pain.

There are several risk factors associated with the development of a dry socket. These include smoking, inadequate dental hygiene, extraction of wisdom teeth, use of oral contraceptive pills, and a previous history of dry socket.

Thiamine deficiency is frequently seen in individuals who are dependent on alcohol. This is primarily due to their inadequate diet, the presence of gastritis which affects thiamine absorption, and the fact that thiamine is involved in alcohol metabolism as a coenzyme. If left untreated, thiamine deficiency can lead to Wernicke’s encephalopathy, which can further progress to Korsakoff’s syndrome.

It is important to note that administering glucose-containing intravenous fluids without thiamine to a patient with chronic thiamine deficiency can trigger Wernicke’s encephalopathy. Therefore, individuals undergoing detoxification should receive parenteral high-potency B complex vitamins (Pabrinex) as a preventive treatment. However, it is crucial to have resuscitation facilities available during administration due to the risk of anaphylaxis. The risk of anaphylaxis is lower when the drug is given intramuscularly (IM). A daily dose of one pair of ampoules of Pabrinex, containing 250 mg of thiamine, should be administered IM or intravenously (IV) for a period of three to five days.

Once the 3-5 day course of Pabrinex is completed, the patient should transition to oral vitamin B Compound-strong and oral thiamine tablets for continued treatment.

For more information, please refer to the NICE pathway for acute alcohol withdrawal.

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.

Heat stroke is a condition characterized by a systemic inflammatory response, where the core body temperature exceeds 40.6°C. It is accompanied by changes in mental state and varying levels of organ dysfunction. Heat stroke occurs when the body’s ability to regulate temperature is overwhelmed by a combination of excessive environmental heat, excessive heat production from metabolic processes (usually due to exertion), and inadequate heat loss.

It is important to consider other clinical conditions that can cause an increased core temperature. Sepsis can present similarly and should be ruled out. Neuroleptic malignant syndrome should be excluded in patients taking phenothiazines or other antipsychotics. Serotonin syndrome should be considered and excluded in patients taking serotonergic medications such as SSRIs. Malignant hyperthermia should be considered in patients with a recent history of general anesthesia. Screening for recreational drug use, particularly cocaine, amphetamines, and ecstasy, is also recommended.

Antipyretics, such as paracetamol, aspirin, and NSAIDs, do not have a role in the treatment of heat stroke. They work by interrupting the change in the hypothalamic set point caused by pyrogens, which is not the case in heat stroke where the hypothalamus is overwhelmed but functioning properly. In fact, antipyretics may be harmful in patients who develop complications in the liver, blood, and kidneys, as they can worsen bleeding tendencies.

Benzodiazepines, like diazepam, can be beneficial in patients experiencing agitation and/or shivering. They help reduce excessive heat production and agitation. In severe cases of agitation, paralysis may be necessary.

There are various cooling techniques recommended for the treatment of heat stroke, but currently, there is limited conclusive evidence on the most effective approach. Some possible methods include simple measures like consuming cold drinks, using fans, applying ice water packs, and spraying tepid water. Cold water immersion therapy can be helpful, but it requires the patient to be stable and cooperative, making it impractical for very sick patients. Advanced cooling techniques, such as cold IV fluids, surface cooling devices (SCD), intravascular cooling devices (ICD), and extracorporeal circuits, may be used for sicker patients.

Traumatic aortic rupture is a relatively common cause of sudden death following major trauma, especially high-speed road traffic accidents (RTAs). It is estimated that 15-20% of deaths from RTAs are due to this injury. If the aortic rupture is promptly recognized and treated, patients who survive the initial injury can fully recover.

Surviving patients often have an incomplete laceration near the ligamentum arteriosum of the aorta. The continuity is maintained by either an intact adventitial layer or a contained mediastinal hematoma, which prevents immediate exsanguination and death.

Detecting traumatic aortic rupture can be challenging as many patients do not exhibit specific symptoms, and other injuries may also be present, making the diagnosis unclear.

Chest X-ray findings can aid in the diagnosis and include fractures of the 1st and 2nd ribs, a grossly widened mediastinum, a hazy left lung field, obliteration of the aortic knob, deviation of the trachea to the right, presence of a pleural cap, elevation and rightward shift of the right mainstem bronchus, depression of the left mainstem bronchus, obliteration of the space between the pulmonary artery and aorta, and deviation of the esophagus (or NG tube) to the right.

Helical contrast-enhanced CT scanning is highly sensitive and specific for detecting aortic rupture, but it should only be performed on hemodynamically stable patients.

Treatment options include primary repair or resection of the torn segment with replacement using an interposition graft. Endovascular repair is also now considered an acceptable alternative approach.

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

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

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

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

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