Laparoscopic surgery involves insufflation of a gas (usually carbon dioxide) into the peritoneal cavity producing a pneumoperitoneum. This causes an increase in intra-abdominal pressure (IAP). Carbon dioxide is insufflated into the peritoneal cavity at a rate of 4–6 litre min−1 to a pressure of 10–20 mm Hg. The pneumoperitoneum is maintained by a constant gas flow of 200–400 ml min−1.

Carbon dioxide is the most frequently used gas for insufflation of the abdomen as it is colourless, non-toxic, non-flammable and has the greatest margin of safety in the event of a venous embolus (highly soluble). It is absorbed readily from the peritoneum, causing an increase in PaCO2. This has direct, as well as indirect (by raising catecholamine levels), effects on the cardiovascular system. Thus, tachycardia, increased cardiac contractility and reduction in the diastolic filling can result in decreased myocardial oxygen supply to demand ratio and greater risk of myocardial ischaemia.

Internal haemorrhoids are formed by varicosities of the branches of the superior rectal vein.
External haemorrhoids are formed by varicosities of the branches of the inferior rectal vein.

Patient-controlled analgesia (PCA) is a delivery system with which patients self-administer predetermined doses of analgesic medication to relieve their pain. The use of PCA in hospitals has been increasing because of its proven advantages over conventional intramuscular injections. These include improved pain relief, greater patient satisfaction, less sedation and fewer postoperative complications.

Hirschsprung’s disease (also known as aganglionic megacolon) leads to colon enlargement due to bowel obstruction by an aganglionic section of bowel that starts at the anus. A blockage is created by a lack of ganglion cells needed for peristalsis that move the stool. 1 in 5000 children suffer from this disease, with boys affected four times more commonly than girls. It develops in the fetus in early stages of pregnancy. Symptoms include not having a first bowel movement (meconium) within 48 hours of birth, repeated vomiting and a swollen abdomen. Two-third of cases are diagnosed within 3 months of birth. Some children may present with delayed toilet training and some might not show symptoms till early childhood. Diagnosis is by barium enema and rectal biopsy (showing lack of ganglion cells).

This patient has an axillary vein thrombosis. It classically presents with pain and swelling of the affected limb. Venous duplex scan is needed to exclude a thrombus.

Primary proximal upper-extremity deep vein thrombosis (UEDVT) is less common than its secondary forms. The most common primary form is effort-related thrombosis, also called Paget-Schroetter syndrome. It usually occurs in, otherwise, healthy young men who report, before the onset of thrombosis, vigorous arm exercise such as lifting weights, playing badminton/tennis, pitching a baseball, or performing repetitive overhead activities, such as painting or car repair. Most patients with effort-related UEDVT have an underlying venous thoracic outlet syndrome (VTOS). Secondary causes of UEDVT include central line insertion, malignancy, or pacemakers.

Patients with UEDVT typically present with heaviness, discomfort, pain, paraesthesia, and swelling of the affected arm. Physical examination may reveal pitting oedema, redness, or cyanosis of the involved extremity; visible collateral veins at the shoulder or upper arm; and fever.

Diagnosis is made by:
1. FBC: platelet function
2. Coagulation profile
3. Liver function tests
4. Venous duplex scan: investigation of choice, provides information relating to flow and characteristics of the vessels.
5. D-dimer testing
6. CT scan: for VTOS

Treatment options for primary UEDVT are as follows:
1. Anticoagulation therapy should be undertaken with a once-daily regimen of LMWH or fondaparinux for at least five days, followed by vitamin K antagonists for at least three months. Unfractionated heparin instead of LMWH is recommended for patients with renal failure or for those treated with CDT.

2. Early thrombus removal and restoration of venous patency aim should be done immediately after starting the patient on heparin. Catheter-based therapy is recommended for patients with proximal UEDVT of recent onset and severe symptoms, low risk for bleeding complications, and good functional status.

Injury to the accessory nerve denervates the trapezius muscle so that the person will no longer be able to raise the acromion of the shoulder. The dorsal scapular nerve supplies the rhomboids i.e. major and minor and the levator scapulae so that injury to this nerve weakens retraction of the scapula. The greater occipital nerve is responsible for sensation of the posterior scalp. The axillary nerve innervates the deltoid muscle which is responsible for abduction of the arm and the suprascapular nerve is responsible for rotating the humerus laterally. Cutaneous nerves supply the skin.

The middle cerebral artery is a major artery that supplies blood to the cerebrum. It continues from the internal carotid artery up into the lateral sulcus. The middle cerebral artery mainly supplies the lateral aspect of the cerebral cortex, anterior aspect of the temporal lobes and the insular cortices.
Functional areas supplied by this vein are as follows:
The motor and pre-motor areas
The somato-sensory
Auditory areas
Motor speech
Sensory speech
Pre-frontal area
Occlusion of the middle cerebral artery results in:
i) A severe contralateral hemiplegia, most marked in the upper extremity and face
ii) A contralateral sensory impairment worse in the upper part of the body

Bile leak may be classified into a minor leak with low output drainage (<300 ml of bile/24 hours) or leaks due to major bile duct injury with high output drainage (>300 ml/24 hours).

The majority of minor bile leak results from Strasberg type A injuries with intact biliary-enteric continuity and includes leaks from cystic duct (CD) stump (55%-71%) or small (less than 3 mm) subsegmental duct in gall bladder (GB) bed (16%) and minor ducts like cholecystohepatic duct or supravesicular duct of Luschka (6%). An injury to the supravesicular duct occurs if the surgeon dissects into the liver bed while separating the gall bladder. This duct does not drain the liver parenchyma.
A leak from the cystic duct stump may occur from clip failure due to necrosis of the stump secondary to thermal injury/pressure necrosis or when clips are used in situations where ties are appropriate (acute cholecystitis) and in a significant majority from distal bile duct obstruction caused by a retained stone and resultant blow out of the cystic stump.
Strasberg type C and type D injuries usually present with a minor leak as well. The former results when an aberrant right hepatic duct (RHD) or right posterior sectoral duct (RPSD) is misidentified as the CD and divided because of the anomalous insertion of CD into either of these ducts.
Type D injuries are lateral injuries to the extrahepatic ducts (EHD) caused by cautery, scissors or clips.

High output biliary fistulas are the result of major transactional injury of EHD (Strasberg type E). Here the common bile duct (CBD) is misidentified as the CD and is clipped, divided and excised. This not only results in a segmental loss of the EHD but often associated with injury or ligation of right hepatic artery as well. Such devastating injuries are peculiar to LC and have been described by Davidoff as “classic laparoscopic biliary injury”.

Early recognition is the most important part of the management of bile leak due to iatrogenic injuries.
Unfortunately, most of the bile duct injuries are not recognized preoperatively. Optimal management of BDI detected postoperatively requires good coordination between the radiologist, endoscopists and an experienced hepatobiliary surgeon.

There is a scope of re-laparoscopy, within 24 hours of surgery, in situations where a low output fistula (<300 ml/day) is confirmed (by reviewing the operative video), to be because of a slipped CD clip. Through lavage, clipping or tying the CD stump with an endoloop may be a simple solution. Such an approach is not useful after 24 hours as inflammatory adhesions and oedema will make the job difficult. If low output controlled biliary fistula is detected after 24 hours, a wait and watch policy should be followed as many of the minor leaks will close within 5 to 7 days. If the leak fails to resolve or if the drainage amount is >300 ml/day (high output), an ERCP should be performed both to delineate the biliary tree and some therapeutic interventions if indicated.

Cryptosporidium parvum is one of several species that causes cryptosporidiosis, a parasitic disease of the mammalian intestinal tract. Primary symptoms of C. parvum infection are acute, watery, and non-bloody diarrhoea. C. parvum infection is of particular concern in immunocompromised patients, where diarrhoea can reach 10–15 l per day.

A small benign tumour, namely intraductal papilloma is most common in women between 35-55 years of age. It is also the commonest cause of spontaneous discharge from a single duct. A lump below the nipple may be sometimes palpable. Ultrasound and ductography are useful investigations., along with cytology of discharge to assess the presence of malignant cells. Confirmation is by breast biopsy.

Created by the small intestinal cells, chylomicrons are large lipoprotein molecules which transport lipids to the liver, adipose, cardiac and skeletal tissue. Chylomicrons are mainly composed of triglycerides (,85%) along with some cholesterol and cholesteryl esters. Apo B-48 is the main apolipoprotein content.

Carbachol (carbamylcholine) is a cholinergic agent, a choline ester and a positively charged quaternary ammonium compound. It is primarily used for various ophthalmic purposes, such as for treating glaucoma, or for use during ophthalmic surgery. It is usually administered topically to the eye or through intraocular injection. It is not well absorbed in the gastro-intestinal tract and does not cross the blood–brain barrier.

Cyclophosphamide is used to treat various types of cancer and autoimmune disorders. The main use of cyclophosphamide is in combination with other chemotherapy agents in the treatment of lymphomas, some forms of leukaemia and some solid tumours. Side-effects include nausea and vomiting, bone marrow suppression, stomach ache, diarrhoea, darkening of the skin
ails, alopecia, lethargy, and haemorrhagic cystitis. Cyclophosphamide is itself carcinogenic, potentially causing transitional cell carcinoma of the bladder as a long-term complication.

Answer: Myoglobin

When muscle is damaged, a protein called myoglobin is released into the bloodstream. It is then filtered out of the body by the kidneys. Myoglobin breaks down into substances that can damage kidney cells.
Compartment syndrome is a painful condition that occurs when pressure within the muscles builds to dangerous levels. This pressure can decrease blood flow, which prevents nourishment and oxygen from reaching nerve and muscle cells.

Compartment syndrome can be either acute or chronic.

Acute compartment syndrome is a medical emergency. It is usually caused by a severe injury. Without treatment, it can lead to permanent muscle damage.

Chronic compartment syndrome, also known as exertional compartment syndrome, is usually not a medical emergency. It is most often caused by athletic exertion. Compartments are groupings of muscles, nerves, and blood vessels in your arms and legs. Covering these tissues is a tough membrane called a fascia. The role of the fascia is to keep the tissues in place, and, therefore, the fascia does not stretch or expand easily.
Compartment syndrome develops when swelling or bleeding occurs within a compartment. Because the fascia does not stretch, this can cause increased pressure on the capillaries, nerves, and muscles in the compartment. Blood flow to muscle and nerve cells is disrupted. Without a steady supply of oxygen and nutrients, nerve and muscle cells can be damaged.

In acute compartment syndrome, unless the pressure is relieved quickly, permanent disability and tissue death may result. This does not usually happen in chronic (exertional) compartment syndrome.

Compartment syndrome most often occurs in the anterior (front) compartment of the lower leg (calf). It can also occur in other compartments in the leg, as well as in the arms, hands, feet, and buttocks.

Acute compartment syndrome usually develops after a severe injury, such as a car accident or a broken bone. Rarely, it develops after a relatively minor injury.

Conditions that may bring on acute compartment syndrome include:

A fracture.
A badly bruised muscle. This type of injury can occur when a motorcycle falls on the leg of the rider, or a football player is hit in the leg with another player’s helmet.
Re-established blood flow after blocked circulation. This may occur after a surgeon repairs a damaged blood vessel that has been blocked for several hours. A blood vessel can also be blocked during sleep. Lying for too long in a position that blocks a blood vessel, then moving or waking up can cause this condition. Most healthy people will naturally move when blood flow to a limb is blocked during sleep. The development of compartment syndrome in this manner usually occurs in people who are neurologically compromised. This can happen after severe intoxication with alcohol or other drugs.
Crush injuries.
Anabolic steroid use. Taking steroids is a possible factor in compartment syndrome.
Constricting bandages. Casts and tight bandages may lead to compartment syndrome. If symptoms of compartment syndrome develop, remove or loosen any constricting bandages.

Unless given IV, a drug must cross several semipermeable cell membranes before it reaches the systemic circulation. Drugs may cross cell membranes by diffusion, amongst other mechanisms. The rate of diffusion of a substance is proportional to the difference in the concentration of the diffusing substance between the two sides of the membrane, the temperature of the solution, the permeability of the membrane and, in the case of ions, the electrical potential difference between the two sides of the membrane.

The boundaries given define the inguinal triangle which is the site for direct inguinal hernias. Indirect inguinal hernias occur lateral to the inferior epigastric vessels.
Femoral hernias protrude through the femoral ring, into the femoral canal.
Umbilical hernias protrude through a defect in the umbilical area.
Obturator hernias, occur through the obturator foramen. These are very rare.

The short gastric arteries arise from the end of the splenic arteries and form five to seven branches. The short gastric arteries inside the gastrosplenic ligament from the left to the right, supply the greater curvature of the stomach. The hepatic artery proper runs inside the hepatoduodenal ligament. The right gastric artery and the left gastric artery are contained in the hepatogastric ligament. The caudal pancreatic artery branches off from the splenic artery and supplies the tail of the pancreas. The middle colic artery supplies the transverse colon. The splenic artery does not travel in the gastrosplenic ligament and so it would not be damaged by a tear to this ligament.

A sperm granuloma is a lump of extravasated sperm that appears along the vasa deferentia or epididymides in vasectomized men.
Sperm granulomas are rounded or irregular in shape, one millimetre to one centimetre or more, with a central mass of degenerating sperm surrounded by tissue containing blood vessels and immune system cells. Sperm granulomas can be either asymptomatic or symptomatic (i.e., either not painful or painful, respectively). If it is painful, it can be treated using over-the-counter anti-inflammatory /pain medication. If it causes unbearable discomfort, it may need to be surgically removed. However, they generally heal by themselves. Statistics suggest that between 15-40% of men may develop a granuloma post-vasectomy.

The combined effort of the lateral pterygoid muscles results in the protrusion of the mandible. The lateral pterygoid muscle is a muscle of mastication located superiorly to the medial pterygoid muscle and has two heads. The superior head originates on the infratemporal surface and infratemporal crest of the greater wing of the sphenoid bone, and the inferior head on the lateral surface of the lateral pterygoid plate. The insertion of this muscle is on the front margin of the articular disc of the temporomandibular joint. The unilateral contraction of the pterygoid muscle results in the laterotrusion of the mandible. It is important to note that the lateral pterygoid muscle is the only muscle of mastication that can open the jaw.

The patient mostly has an appendicular mass.
At present, the treatment of choice for uncomplicated acute appendicitis in adults continues to be surgical. The inflammation in acute appendicitis may sometimes be enclosed by the patient’s own defence mechanisms, by the formation of an inflammatory phlegmon or a circumscribed abscess. The management of these patients is controversial. An immediate appendectomy may be technically demanding. The exploration often ends up in an ileocecal resection or a right-sided hemicolectomy. Recently, the conditions for conservative management of these patients have changed due to the development of computed tomography and ultrasound, which has improved the diagnosis of enclosed inflammation and made drainage of intra-abdominal abscesses easier. New efficient antibiotics have also given new opportunities for nonsurgical treatment of complicated appendicitis. The traditional management of these patients is nonsurgical treatment followed by interval appendectomy to prevent a recurrence. The need for interval appendectomy after successful nonsurgical treatment has recently been questioned because the risk of recurrence is relatively small.
In patients with suspicion of contained appendiceal inflammation, based on a palpable mass or long duration of symptoms, the diagnosis should be confirmed by imaging techniques, especially CT scan. The patient should receive primary nonsurgical treatment with antibiotics and abscess drainage as needed. After successful nonsurgical treatment, no interval appendectomy is indicated in some cases, but the patient should be informed about the risk of recurrence especially in the presence of appendicolith. The risk of missing another underlying condition (cancer or CD) is low, but motivates a follow-up with a colon examination and/or a CT scan or US, especially in patients above the age of 40 years.

Branches that stem from the abdominal aorta can be divided into three: the visceral branches, parietal branches and terminal branches. Of the visceral branches, the suprarenal, renal, testicular and ovarian arteries are paired while the coeliac artery and superior and inferior mesenteric arteries are unpaired. Of the parietal branches the inferior phrenic and lumbar arteries are paired while the middle sacral artery is unpaired. The terminal branches i.e. the common iliac arteries are paired.

Mycosis fungoides is a chronic T-cell lymphoma that involves the skin and less commonly, the internal organs such as nodes, liver, spleen and lungs. It is usually diagnosed in patients above 50 years and the average life expectancy is 7-10 years. It is insidious in onset and presents as a chronic, itchy rash, eventually spreading to involve most of the skin. Lesions are commonly plaque-like, but can be nodular or ulcerated. Symptoms include fever, night sweats and weight loss. Skin biopsy is diagnostic. However, early cases may pose a challenge due to fewer lymphoma cells. The malignant cells are mature T cells (T4+, T11+, T12+). The epidermis shows presence of characteristic Pautrier’s micro abscesses are present in the epidermis.

The superior thyroid artery arises from the external carotid artery just below the level of the greater cornu of the hyoid bone and ends in the thyroid gland. This artery must be ligated at the thyroid when conducting a thyroidectomy. If the artery is severed, but not ligated, it will bleed profusely. In order to gain control of the bleeding, the surgeon may need to extend the original incision laterally to ligate the artery at its origin at the external carotid artery. The external laryngeal branch of the superior laryngeal nerve courses in close proximity to the superior thyroid artery, making it at risk for injury during surgery.

Image guided core biopsy (US-directed biopsy) is performed for lesions that are palpable, but also for non-palpable, mammogram-detected lesions with a corresponding abnormality visualized on US. US-guided core biopsy is technically easier than stereotactic-guided biopsy as real-time imaging allows the surgeon to visualize the biopsy as it occurs. Using sterile technique and local anaesthesia, a small puncture is made with an 11-knife blade and the needle is placed near the edge of the lesion and fired, which inserts it into the lesion for a sample to be retrieved. When placed parallel to the needle the position of the needle can be visualized on US.

If the core biopsy result is benign and is concordant with imaging findings, continued surveillance is acceptable. If the result is indeterminate or image-discordant, surgical excision is indicated to rule out malignancy. In order to determine the appropriate management and surveillance of a lesion, the histologic, imaging, and clinical findings must be taken into account for an assessment of concordance to be performed. In addition, surgical excision is indicated for a core biopsy that demonstrates atypical hyperplasia (lobular or ductal) or lobular carcinoma in situ or neoplasia as the incidence of coexisting ductal carcinoma in situ or invasive carcinoma may be as high as 30% due to potential sampling error.

Extension of the humerus is a function of the latissimus dorsi. This muscle is supplied by the thoracodorsal nerve which is a branch of the posterior cord of the plexus whose fibres are derived from cranial nerves V, VI and VII.

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children.
Rhabdomyosarcoma usually manifests as an expanding mass. Tumours in superficial locations may be palpable and detected relatively early, but those in deep locations (e.g., retroperitoneum) may grow large before causing symptoms.
Symptoms depend on the location of the tumour, and pain may be present. Typical presentations of nonmetastatic disease, by location, are as follows:
Orbit: Proptosis or dysconjugate gaze
Paratesticular: Painless scrotal mass, testes are felt separately
Prostate: Bladder or bowel difficulties
Uterus, cervix, bladder: Menorrhagia or metrorrhagia
Vagina: Protruding polypoid mass (botryoid, meaning a grapelike cluster)
Extremity: Painless mass
Parameningeal (ear, mastoid, nasal cavity, paranasal sinuses, infratemporal fossa, pterygopalatine fossa): Upper respiratory symptoms or pain

In the international classification of rhabdomyosarcoma, there are 5 recognized variants: embryonal, alveolar, botryoid embryonal, spindle cell embryonal and anaplastic. The most common variant is embryonal, most associated with tumours of the genitourinary tract and the head and neck. Histologically, the embryonal subtype resembles that of a 6- to an 8-week old embryo.

Dumping syndrome is the effect of altered gastric reservoir function, abnormal postoperative gastric motor function, and/or pyloric emptying mechanism. Clinically significant dumping syndrome occurs in approximately 10% of patients after any type of gastric surgery and in up to 50% of patients after laparoscopic Roux-en-Y gastric bypass. Dumping syndrome has characteristic alimentary and systemic manifestations. It is a frequent complication observed after a variety of gastric surgical procedures, such as vagotomy, pyloroplasty, gastrojejunostomy, and laparoscopic Nissan fundoplication. Dumping syndrome can be separated into early and late forms, depending on the occurrence of symptoms in relation to the time elapsed after a meal.
Postprandially, the function of the body of the stomach is to store food and to allow the initial chemical digestion by acid and proteases before transferring food to the gastric antrum. In the antrum, high-amplitude contractions triturate the solids, reducing the particle size to 1-2 mm. Once solids have been reduced to this desired size, they are able to pass through the pylorus. An intact pylorus prevents the passage of larger particles into the duodenum. Gastric emptying is controlled by the fundic tone, antropyloric mechanisms, and duodenal feedback. Gastric surgery alters each of these mechanisms in several ways.

The late dumping syndrome is suspected in the person who has symptoms of hypoglycaemia in the setting of previous gastric surgery, and this late dumping can be proven with an oral glucose tolerance test (hyperinsulinemic hypoglycaemia), as well as gastric emptying scintigraphy, which shows the abnormal pattern of initially delayed and then accelerated gastric emptying.

The clinical presentation of dumping syndrome can be divided into GI symptoms and vasomotor symptoms. GI symptoms include early satiety, crampy abdominal pain, nausea, vomiting, and explosive diarrhoea. Vasomotor symptoms include diaphoresis, flushing, dizziness, palpitations, and an intense desire to lie down.

The expression of these symptoms varies in different individuals. Most patients with early dumping have both GI and vasomotor symptoms, while patients with late dumping have mostly vasomotor symptoms. Patients with severe dumping often limit their food intake to avoid symptoms. This leads to weight loss and, over time, malnutrition.

Early dumping syndrome generally occurs within 15 minutes of ingesting a meal and is attributable to the rapid transit of food into the small intestine, whereas late dumping syndrome occurs later and may be attributed to hypoglycaemia with tremors, cold sweats, difficulty in concentrating, and loss of consciousness.

Early dumping systemic symptoms are as follows:
Desire to lie down
Palpitations
Fatigue
Faintness
Syncope
Diaphoresis
Headache
Flushing

Early dumping abdominal symptoms are as follows:
Epigastric fullness
Diarrhoea
Nausea
Abdominal cramps
Borborygmi

Late dumping symptoms are as follows:
Perspiration
Shakiness
Difficulty to concentrate
Decreased consciousness
Hunger

neutrophils are the most abundant cell type of the WBC. These phagocytes are found normally in the blood and increase in number are seen during an acute inflammation. These the percentages of WBC in blood Neutrophils: 40 to 60%
Lymphocytes: 20 to 40%
Monocytes: 2 to 8%
Eosinophils: 1 to 4%
Basophils: 0.5 to 1%
Band (young neutrophil): 0 to 3%. eosinophils, basophils, neutrophils are known as granulocytes and monocytes and lymphocytes as agranulocytes.

Hageman factor/factor XII in the intrinsic pathway activates prekallikrein and factor XI. Deficiency will not cause excessive bleeding as other coagulation factors will be utilized but the PTT will be greater than 200 seconds.
Thromboxane promotes platelet aggregation and causes vasoconstriction.
Plasmin, which is cleaved from plasminogen acts as an anticoagulant which breaks down thrombi.
Platelet activating factor promotes platelet aggregation and is also chemotactic to neutrophils.
Histamine acts as a vasodilator.
Platelet inhibiting factor acts an anticoagulant.
Renin is a hormone released from the kidney that causes vasoconstriction and water retention.

An increase in the frequency of sound waves results in a change in the position of maximal displacement of the basilar membrane in the cochlea. Low pitch sound produces maximal displacement towards the cochlear apex and greatest activation of hair cells there. With an increasing pitch, the site of greatest displacement moves towards the cochlear base. However, increased amplitude of displacement, increase in the number of activated hair cells, increased frequency of discharge of units in the auditory nerve and increase in the range of frequencies to which such units respond, are all seen in increases in the intensity or a sound stimulus.