Hyperkalaemia causes a rapid reduction in resting membrane potential leading to increased cardiac depolarisation and muscle excitability. This in turn results in ECG changes which can rapidly progress to ventricular fibrillation or asystole. Very distinctive ECG changes that progressively change as the K+level increases:
K+>5.5 mmol/l – peaked T waves (usually earliest sign of hyperkalaemia), repolarisation abnormalities
K+>6.5 mmol/l – P waves widen and flatten, PR segment lengthens, P waves eventually disappear
K+>7.0 mmol/l – Prolonged QRS interval and bizarre QRS morphology, conduction blocks (bundle branch blocks, fascicular blocks), sinus bradycardia or slow AF, development of a sine wave appearance (a pre-terminal rhythm)
K+>9.0 mmol/l – Cardiac arrest due to asystole, VF or PEA with a bizarre, wide complex rhythm.

Diazepam boosts GABA’s effects, giving it sedative, hypnotic, anxiolytic, anticonvulsant, and muscle-relaxing properties. It can be administered orally, rectally, or intravenously.

With a half-life of 20-100 hours, it is a long-acting benzodiazepine. Midazolam, oxazepam, and alprazolam are examples of short-acting benzodiazepines with a half-life of less than 12 hours (Xanax).

If used in the presence of hepatic impairment, benzodiazepines can cause coma. If treatment is necessary, benzodiazepines with shorter half-lives should be used in lower doses. Diazepam is a sedative that crosses into breast milk and should be avoided by breastfeeding mothers.

The facial nerve divides into five terminal branches once in the parotid gland.
1. The temporal branch innervates muscles in the temple, forehead and supraorbital areas.
2. The zygomatic branch innervates muscles in the infraorbital area, the lateral nasal area and the upper lip.
3. The buccal branch innervates muscles in the cheek, the upper lip and the corner of the mouth.
4. The marginal mandibular branch innervates muscles of the lower lip and chin.
5. The cervical branch innervates the platysma muscle.

Common adverse effects include nausea and vomiting, sedation, dizziness, headache, blurred vision and ataxia. These adverse effects are dose related and are most common at the start of treatment.
Other adverse effects include:
Allergic skin reactions (and rarely, more serious dermatological conditions)
Hyponatraemia (avoid concomitant use with diuretics)
Leucopenia, thrombocytopenia and other blood disorders including aplastic anaemia
Hepatic impairment

A p value < 0.05:is statistically significantmeans that the probability of obtaining a given result by chance is less than 1 in 20means the null hypothesis is rejectedmeans there is evidence of an association between a variable and an outcomeNote that this does not tell us whether the result is clinically significant.

Cefuroxime and other cephalosporin antibiotics are bactericidal ß-lactam antibiotics. They work similarly to penicillins in that they prevent cross-linking between the linear peptidoglycan polymer chains that make up the bacterial cell wall. As a result, they prevent the formation of cell walls.
The following is a summary of the various mechanisms of action of various types of antimicrobial agents:

1) Inhibition of cell wall synthesis
Penicillins
Cephalosporins
Vancomycin

2) Disruption of cell membrane function
Polymyxins
Nystatin
Amphotericin B

3) Inhibition of protein synthesis
Macrolides
Aminoglycosides
Tetracyclines
Chloramphenicol

4) Inhibition of nucleic acid synthesis
Quinolones
Trimethoprim
5-nitroimidazoles
Rifampicin

5) Anti-metabolic activity
Sulphonamides
Isoniazid

Blood transfusion can be a life-saving treatment with significant clinical benefits, but it also comes with a number of risks and potential complications, including:
Immunological side effects
Errors in administration (episodes of ‘wrong blood’)
Viruses and Infections (bacterial, viral, possibly prion)
Immunodilution

A culture of better safety procedures as well as steps to reduce the use of transfusion has emerged as a result of growing awareness of avoidable risk and improved reporting systems. Transfusion errors, on the other hand, continue to occur, and some serious adverse reactions go unreported.

Transfusion-associated graft-vs-host disease (TA-GVHD) is a rare blood transfusion complication that causes fever, rash, and diarrhoea 1-4 weeks after the transfusion. Pancytopenia and liver function abnormalities are common laboratory findings.

TA-GVHD, unlike GVHD following allogeneic marrow transplantation, causes profound marrow aplasia with a mortality rate of >90%. Survival is uncommon, with death occurring within 1-3 weeks of the onset of symptoms.

Because of immunodeficiency, severe immunosuppression, or shared HLA antigens, viable T lymphocytes in blood components are transfused, engraft, and react against the recipient’s tissues, and the recipient is unable to reject the donor lymphocytes.
The following is a list of the most common transfusion reactions and complications:

1) Reaction to a febrile transfusion
The temperature rises by one degree from the baseline. Chills and malaise are also possible symptoms.
The most common response (1 in 8 transfusions).
Cytokines from leukocytes in transfused red cell or platelet components are usually to blame.
Only supportive. The use of paracetamol is beneficial.

2) Acute haemolytic reaction is a type of haemolytic reaction that occurs when the
Fever, chills, pain at the transfusion site, nausea, vomiting, and dark urine are all symptoms of a transfusion reaction.
Early on, many people report a sense of ‘impending doom.’
The most serious reaction. ABO incompatibility is frequently caused by a clerical error.
STOP THE TRANSFUSION OF INFORMATION. IV fluids should be given. It’s possible that diuretics will be required.

3) Haemolytic reaction that is delayed
It usually happens 4 to 8 days after a blood transfusion.
Fever, anaemia, jaundice, and haemoglobinuria are all symptoms that the patient has.
Positive Coombs test for direct antiglobulin.
Because of the low titre antibody, it is difficult to detect in a cross-match, and it is unable to cause lysis at the time of transfusion.
The majority of delayed haemolytic reactions are harmless and do not require treatment.
Anaemia and renal function should be monitored and treated as needed.

4) Reaction to allergens
Foreign plasma proteins are usually to blame, but anti-IgA could also be to blame.
Urticaria, pruritus, and hives are typical allergic reactions. It’s possible that it’s linked to laryngeal oedema or bronchospasm.
Anaphylaxis is a rare occurrence.
Antihistamines can be used to treat allergic reactions symptomatically. It is not necessary to stop transfusions.
If the patient develops anaphylaxis, the transfusion should be stopped and the patient should be given adrenaline and treated according to the ALS protocol.

5) TRALI (Transfusion Related Acute Lung Injury)
Within 6 hours of transfusion, there was a sudden onset of non-cardiogenic pulmonary oedema.
It’s linked to the presence of antibodies to recipient leukocyte antigens in the donor blood.
The most common cause of death from transfusion reactions is this.
STOP THE TRANSFUSION OF INFORMATION. Oxygen should be given to the patient. Around 75% of patients will require aggressive respiratory support.
The use of diuretics should be avoided.

6) TACO (Transfusion Associated Circulatory Overload)
Acute or worsening respiratory distress within 6 hours of a large blood transfusion. Fluid overload and pulmonary and peripheral oedema can be seen. Rapid blood pressure rises are common. BNP is usually 1.5 times higher than it was before the transfusion. It is most common in the elderly and those who have chronic anaemia.

Blood transfusions should be given slowly, over the course of 3-4 hours.

Infectious mononucleosis can be diagnosed using specific EBV antibodies and a variety of unrelated non-EBV heterophile antibodies.

Heterophile antibodies:
About 70-90% of patients with EBV infectious mononucleosis produce antibodies against an antigen produced in one species that react against antigens from other species called heterophile antibodies. False positives can be seen with rubella, hepatitis, SLE, malaria, toxoplasmosis, lymphoma and leukaemia.

These antibodies can be detected by two main screening tests:
The monospot test uses horse red blood cells. It agglutinates in the presence of heterophile antibodies.
Paul-Bunnell test uses sheep red blood cells. The blood agglutinates in the presence of heterophile antibodies.

EBV-specific antibodies:
Patients can remain heterophile-negative after six weeks and are then considered to be heterophile-negative and should be tested for EBV-specific antibodies. EBV-specific antibodies test are helpful if a false positive heterophile antibody test is suspected.
The indirect Coombs test is used to detect in-vitro antibody-antigen reactions. It is typically used in antenatal antibody screening and in preparation for blood transfusion.
Heterophile antibody tests are generally not positive in the incubation period of infectious mononucleosis (4-6 weeks) before the onset of symptoms.

The pressure measured in the right atrium or superior vena cava is known as central venous pressure (CVP). In a spontaneously breathing subject, the usual CVP value is 0-8 cmH2O (0-6 mmHg).

The structure of the CVP waveform is as follows:
The CVP’s components are listed in the table below:
Component of the waveform
The cardiac cycle phase.
mechanical event
mechanical event Diastole 
Atrial contraction
a wave 
C  wave 
v wave
Early systole
The tricuspid valve closes and bulges 
Late Systole 
Filling of the atrium with systolic blood 
x descent
y descent
Mid systole
Relaxation of the atrium 
Early diastole
Filling of the ventricles at an early stage

Hyperaemia is the process where the body adjusts blood flow to meet the metabolic needs of different tissues in health and disease. Vasoactive mediators that take part in this process include K+, adenosine, CO2, H+, phosphates and H2O2. Although the mechanism is not clear, all these mediators likely contribute to some extent at different points.

Specific organs are more sensitive to specific metabolites:
K+ and adenosine are the most potent vasodilators in skeletal muscles

CO2 and K+ are the most potent vasodilators in cerebral circulation.