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BPT/BOT Paper XII - General Surgery: Past Year Questions & Answers (2015-2025)

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QUESTION 1: Define and Classify Shock. Discuss Management of Hemorrhagic/Hypovolemic Shock

Definition

Classification of Shock (Table)

Classes of Hemorrhagic Shock (ATLS Classification)

• This is a life-threatening emergency.

Management of Hemorrhagic Shock - "ABCDE" Approach

1. Direct pressure on external wounds
2. IV access - two large-bore (16G) peripheral IVs
3. Fluid resuscitation:
   • Initial bolus: 1-2L warm crystalloid (Ringer's Lactate preferred over NS)
   • Damage Control Resuscitation: Blood products in 1:1:1 ratio (PRBC : FFP : Platelets)
   • Permissive hypotension - target SBP 80-90 mmHg until surgical hemorrhage control (not in TBI)
   • Avoid over-resuscitation with crystalloid (causes ARDS, coagulopathy)
4. Transfusion trigger: Hb <7 g/dL (or <10 in cardiac patients/elderly)
5. Surgical hemorrhage control - source control is paramount

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QUESTION 2: Factors Affecting Wound Healing & Management of Chronic Ulcers

Wound Healing Types

• Primary intention: Wound edges reapproximated soon after injury (sutured/stapled)
• Secondary intention: Wound left open, heals from base by granulation
• Tertiary intention (Delayed primary): Wound cleaned, then closed after 4-5 days

Phases of Wound Healing

1. Haemostasis (immediate): Platelet plug, clot formation, vasoconstriction
2. Inflammatory phase (0-5 days): Neutrophils then macrophages clean debris; growth factor release
3. Proliferative phase (5 days-3 weeks): Fibroblasts deposit collagen, angiogenesis, re-epithelialization
4. Remodeling phase (3 weeks-2 years): Collagen remodeling; wound reaches ~80% tensile strength

Factors Affecting Wound Healing

• Wound infection (most common cause of delayed healing)
• Poor blood supply / ischemia
• Foreign body / necrotic tissue
• Wound tension
• Wound size and depth
• Previous irradiation

• Malnutrition (protein, Vit C, Zinc deficiency)
• Diabetes mellitus (impairs neutrophil function, microangiopathy)
• Steroids / immunosuppressants
• Chemotherapy
• Advanced age
• Anemia / hypovolemia
• Malignancy

Management of Chronic Ulcers

• T - Tissue debridement (remove necrotic/sloughy tissue - surgical, enzymatic, or larval therapy)
• I - Infection control (swab, treat with topical/systemic antibiotics; silver dressings)
• M - Moisture balance (appropriate dressings - hydrocolloid, foam, alginate)
• E - Edge advancement (stimulate epithelial migration; skin grafting if needed)

• Venous ulcers: Four-layer compression bandaging, leg elevation, treat venous reflux
• Arterial ulcers: Revascularization (angioplasty or bypass), avoid compression
• Diabetic ulcers: Glycemic control, offloading, debridement, check for osteomyelitis
• Pressure ulcers: Pressure relief, nutritional support, wound care

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QUESTION 3(a): Complications of Blood Transfusion

Immediate (within 24 hours):

Delayed:

• Delayed hemolytic reaction (1-2 weeks): Antibodies to minor blood group antigens (Kell, Duffy)
• Post-transfusion purpura: Thrombocytopenia 5-10 days post-transfusion
• Graft-versus-host disease (GVHD): Donor T-lymphocytes attack immunocompromised recipient
• Alloimmunization: Formation of new antibodies
• Iron overload: In chronically transfused patients

Massive Transfusion Complications:

• Hypothermia (transfuse warmed blood)
• Hypocalcemia (citrate chelates calcium)
• Hyperkalemia
• Coagulopathy (dilutional)
• Metabolic acidosis

Infectious complications: HIV, Hepatitis B/C, CMV, syphilis (screened but residual risk)

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QUESTION 3(b): Surgical Site Infections (SSI)

Definition

Classification:

• Superficial incisional SSI: Involves skin and subcutaneous tissue only
• Deep incisional SSI: Involves deep soft tissue (fascia and muscle)
• Organ/space SSI: Involves any organ or space opened/manipulated during surgery

Common Organisms:

• S. aureus (most common), S. epidermidis, Gram-negative rods (E. coli, Pseudomonas), Enterococcus

Risk Factors:

• Wound classification (contaminated/dirty wounds have highest risk)
• Prolonged operating time
• Diabetes, obesity, malnutrition
• Immunosuppression
• Pre-existing infection
• Emergency surgery
• Poor surgical technique (dead space, haematoma)

Prevention:

• Pre-operative hair removal (clipping, not shaving)
• Antiseptic skin preparation (chlorhexidine + alcohol)
• Prophylactic antibiotics within 60 min of incision, stopped within 24 hours
• Maintain normothermia and normoglycemia intraoperatively
• Aseptic technique, minimize dead space

Treatment:

• Superficial: Open wound, culture, antibiotics if spreading cellulitis
• Deep: Surgical debridement + antibiotics
• Vacuum-assisted wound closure (VAC) for large wounds

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QUESTION 3(c): Tension Pneumothorax

Definition

Causes:

• Blunt or penetrating chest trauma
• Iatrogenic (central line insertion, positive pressure ventilation)
• Spontaneous (in ventilated patients especially)

Clinical Features ("5 Ds"):

• Dyspnoea (severe)
• Distended neck veins (JVD due to impaired venous return)
• Decreased breath sounds on affected side
• Deviation of trachea away from affected side
• Dullness to hyperresonance on percussion of affected side
• Hypotension, tachycardia, cyanosis, cardiovascular collapse

Diagnosis:

• Clinical diagnosis - do NOT wait for X-ray in emergency
• CXR (if stable): Absent lung markings, mediastinal shift, depressed diaphragm on affected side

Treatment - Immediate:

1. Needle decompression (first): 14G needle into 2nd intercostal space, mid-clavicular line on affected side - converts to open pneumothorax, relieves pressure
2. Definitive: Chest drain (tube thoracostomy) in 5th intercostal space, anterior axillary line

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QUESTION 3(d): Fluid Replacement in Burns

Initial Assessment - Wallace Rule of Nines:

Resuscitation Formula:

4 mL × Weight (kg) × %TBSA burned = Total fluid in first 24 hours

• Use Ringer's Lactate
• First half in first 8 hours from time of burn (not from admission)
• Second half over next 16 hours

• 4 × 70 × 40 = 11,200 mL in 24 hours
• First 8 hours: 5,600 mL
• Next 16 hours: 5,600 mL

• Urine output: 0.5-1 mL/kg/hr in adults, 1 mL/kg/hr in children
• Avoid both under-resuscitation (acute renal failure) and over-resuscitation (oedema, abdominal compartment syndrome)

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QUESTION 4(a): Classification and Management of Burns

Classification by Depth:

Burns in Special Areas requiring special attention:

Management of Major Burns:

• Stop burning process (remove clothing/chemicals, cool with 15-20°C running water for 20 min)
• Do NOT use ice (causes vasoconstriction and deeper injury)

• Airway - highest priority; inhalation injury present if: singed nasal hair, hoarse voice, carbonaceous sputum, facial burns; early intubation before oedema occludes airway
• Breathing - 100% O2 (for CO poisoning)
• Circulation - IV access (2 large bore), start Parkland formula
• Disability - GCS
• Exposure - calculate %TBSA, keep warm

• Superficial: Dressings (silver sulfadiazine, Mepitel, Aquacel Ag)
• Deep/Full thickness: Early excision and skin grafting within 3-5 days reduces infection and mortality
• Escharotomy for circumferential full-thickness burns (compartment syndrome)

• Nasogastric tube (ileus common) + early enteral nutrition
• Foley catheter for urine output monitoring
• Analgesia (IV morphine/ketamine)
• DVT prophylaxis
• Tetanus prophylaxis
• H2 blockers (prevent Curling's ulcer - stress ulcer of duodenum)

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QUESTION 4(b): Advantages & Disadvantages of Laparoscopic and Robotic Surgery

Laparoscopic Surgery:

• Smaller incisions - reduced wound complications
• Less postoperative pain - less analgesic requirement
• Shorter hospital stay and faster return to work
• Reduced blood loss
• Less adhesion formation
• Better cosmesis
• Magnified view improves visualization

• Loss of tactile feedback (haptics)
• Two-dimensional view (traditional laparoscopy)
• Long learning curve
• Expensive equipment, specialized training needed
• Risk of trocar injuries (bowel, vessels)
• CO2 pneumoperitoneum risks: hypercarbia, deep vein thrombosis, gas embolism
• Limited range of motion of instruments

Robotic Surgery (e.g., da Vinci system):

• Three-dimensional, high-definition visualization
• Wristed instruments - 7 degrees of freedom (superior to laparoscopy's 4)
• Tremor filtration (improves precision)
• Better ergonomics for surgeon
• Useful in confined spaces (prostate, deep pelvis, mediastinum)
• Reduced blood loss, shorter catheterization time (e.g., prostatectomy)
• Shorter hospital stay

• No tactile feedback (even more than laparoscopy)
• Very high cost (equipment + maintenance)
• Large size of robot
• Long setup/docking time
• Requires highly specialized training
• Not suitable for emergencies requiring rapid conversion

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QUESTION 5: Signs & Symptoms in Each Trimester of Pregnancy

First Trimester (0-12 weeks):

• Amenorrhea (missed period - first sign)
• Nausea/morning sickness (hCG peak)
• Breast tenderness and enlargement
• Urinary frequency (uterus compresses bladder)
• Fatigue, dizziness
• Chadwick's sign: Bluish discolouration of vulva and vagina
• Goodell's sign: Softening of cervix
• Hegar's sign: Softening of lower uterine segment

Second Trimester (13-26 weeks):

• Quickening (first fetal movements felt, ~18-20 weeks in primi, ~16-18 in multi)
• Abdominal enlargement becomes obvious
• Disappearance of nausea
• Increased appetite
• Braxton-Hicks contractions begin (painless, irregular)
• Fundal height rises (umbilicus level at ~20 weeks)
• Pigmentation (linea nigra, chloasma/mask of pregnancy)
• Striae gravidarum

Third Trimester (27-40 weeks):

• Progressive abdominal distension
• Dependent oedema (legs, ankles)
• Dyspnoea (diaphragm pushed up)
• Heartburn (relaxed lower oesophageal sphincter)
• Urinary frequency returns (fetal head descends, lightening)
• Braxton-Hicks become more frequent
• Backache (relaxin + shifted centre of gravity)
• Engagement of fetal head (~36 weeks in primigravida)

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QUESTION 6(a): Types of Hearing Aids and Their Indications

Types of Hearing Aids:

General Indications:

• Conductive hearing loss (treatable cause should be managed first)
• Sensorineural hearing loss (bilateral ≥25-40 dB loss)
• Mixed hearing loss
• Age-related hearing loss (presbycusis)
• Functional hearing impairment affecting daily communication

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QUESTION 6(b): Common Inflammation of the Eye (Conjunctivitis)

Conjunctivitis - Definition & Types:

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QUESTION: Degloving Injury & Skin Grafts

Degloving Injury:

• Wound assessment, debridement of devitalized tissue
• Replace avulsed skin as full-thickness graft if viable
• Vacuum-assisted closure (VAC) as temporary coverage
• Split-skin grafting for large areas

Types of Skin Grafts:

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QUESTION: Classify and Manage Hernia (Inguinal Hernia)

Classification of Hernia:

• Reducible: Contents return to abdomen spontaneously or manually
• Irreducible (Incarcerated): Cannot be reduced back
• Obstructed: Bowel in sac is obstructed (no blood supply compromise yet)
• Strangulated: Blood supply cut off - surgical emergency
• Sliding: Part of sac is formed by viscus (e.g., caecum, bladder)

Management of Inguinal Hernia:

1. Tension repair (Bassini, Shouldice): No mesh; primary tissue approximation; higher recurrence
2. Mesh repair (Lichtenstein - tension-free): Gold standard for open repair; low recurrence (<1%)
3. Laparoscopic repair (TEP - Total Extraperitoneal or TAPP - Transabdominal Preperitoneal): Less postoperative pain, faster return to work; preferred for bilateral/recurrent hernias

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QUESTION: Uterine Prolapse - Classification, Clinical Features & Management

Classification (POP-Q / Baden-Walker / Degrees):

Clinical Features:

• Feeling of something coming down PV
• Dragging/heaviness in pelvis
• Urinary symptoms: stress incontinence, frequency, difficulty voiding
• Difficulty with defecation
• Backache (lumbar, relieved by lying down)
• Superficial dyspareunia or inability to have intercourse
• Decubitus ulcer on prolapsed cervix (if chronic)

Management:

• Pelvic floor exercises (Kegel exercises) - mild cases
• Pessary (Ring pessary): Mechanical support; for elderly/medically unfit, postpartum, or as temporary measure
• Oestrogen cream (postmenopausal) - improves tissue tone
• Weight reduction, treat chronic cough/constipation

• Fothergill/Manchester repair: For 2nd degree prolapse with long cervix; amputation of cervix + anterior colporrhaphy
• Vaginal hysterectomy + pelvic floor repair: Definitive; for completed family
• Sacrocolpopexy (abdominal/laparoscopic): Mesh fixation for vault prolapse after hysterectomy
• Le Fort's operation: Obliterative surgery for elderly frail women who don't want/can't have intercourse

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QUESTION: Abdominal Incisions and Incisional Hernia

Types of Abdominal Incisions:

• Adequate exposure of operative field
• Extensile if needed
• Minimal damage to nerves, muscles, blood vessels
• Secure closure without risk of dehiscence
• Good cosmetic result
• Heals with minimal hernia risk

Incisional Hernia:

• Small/asymptomatic: Conservative (truss)
• Surgical: Mesh repair (onlay, sublay/retromuscular, IPOM - laparoscopic intraperitoneal onlay mesh); primary suture repair has 30-50% recurrence vs. <10% with mesh

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QUESTION: Types of Anaesthesia and Their Complications

Classification:

• Patient unconscious; loss of consciousness, analgesia, muscle relaxation
• Stages (Guedel's): Analgesia → Excitement/Delirium → Surgical anaesthesia → Respiratory paralysis
• Components (Triad): Hypnosis + Analgesia + Muscle relaxation
• Agents: Inhalational (sevoflurane, isoflurane), IV (propofol, ketamine, thiopentone)
• Complications: Airway obstruction, aspiration (Mendelson syndrome), laryngospasm, malignant hyperthermia (rare but life-threatening with suxamethonium/volatile agents), post-op nausea/vomiting (PONV), awareness under anaesthesia

• Spinal (Subarachnoid block): LA injected into subarachnoid space (L3-L4 or below); rapid onset; used for lower limb, perineal, lower abdominal surgery. Complications: spinal headache (PDPH), hypotension, high block
• Epidural: LA in epidural space; slower onset; used for labour analgesia, major surgery, post-op pain. Continuous catheter technique. Complications: dural tap, infection, epidural haematoma
• Brachial plexus block: Upper limb surgery
• Nerve blocks: Digital, femoral, sciatic etc.

• Infiltration, topical, or nerve block
• Agents: Lignocaine (lidocaine), Bupivacaine
• Complications: Toxicity (CNS: circumoral numbness, convulsions; CVS: arrhythmias, cardiac arrest); maximum dose must not be exceeded

• Patient sedated but maintains airway; for minor procedures

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QUESTION: Glasgow Coma Scale (GCS)

• GCS 13-15: Mild head injury
• GCS 9-12: Moderate
• GCS 3-8: Severe (intubate)
• GCS <8: Intubate and ventilate

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QUESTION: Keloid vs. Hypertrophic Scar

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QUESTION: Gangrene (Gas Gangrene)

Types of Gangrene:

• Dry gangrene: Ischaemic; no infection; shrivels and demarcates; no odour (arterial disease/diabetes)
• Wet gangrene: Infected ischaemic tissue; rapid spread; putrid odour; systemic sepsis
• Gas gangrene: Clostridial infection producing gas in tissues
• Synergistic gangrene (Fournier's gangrene): Perineal area; mixed organisms

Gas Gangrene:

• Sudden severe pain in wound (out of proportion)
• Brownish/purple discolouration of skin, bronze discolouration
• Blistering with brownish/bloody fluid
• Crepitus (gas in tissue - felt/heard on palpation)
• Foul-smelling (butyric odour)
• Tachycardia, high fever, toxaemia, shock
• Rapidly progressive

1. Immediate radical surgical debridement - wide excision of all affected tissue; amputation if limb involved
2. High-dose IV Penicillin G (+ metronidazole for mixed infection)
3. Hyperbaric oxygen therapy (HBO) - adjunct; O2 toxic to anaerobes
4. IV fluids, blood transfusion, resuscitation
5. Antitoxin (limited evidence)

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QUESTION: Primary and Secondary Survey in Trauma (ATLS)

Primary Survey - "ABCDE":

Secondary Survey:

• Performed after primary survey and initial resuscitation
• Head-to-toe physical examination (head, face, neck, chest, abdomen, pelvis, extremities, back, neurological)
• Detailed history: AMPLE (Allergies, Medications, Past history, Last meal, Events)
• Consider: FAST scan (Focused Assessment with Sonography in Trauma) for haemoperitoneum
• Adjuncts: Chest X-ray, pelvis X-ray, FAST, CT trauma series

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QUESTION: Pneumothorax

Types:

• Simple pneumothorax: Air in pleural space; no mediastinal shift
• Open pneumothorax (sucking chest wound): Chest wall defect; air enters through wound
• Tension pneumothorax: One-way valve mechanism; mediastinal shift; life-threatening (see above)
• Haemopneumothorax: Blood + air

Management:

• Simple small (<20%): Conservative (O2, monitoring)
• Simple large (>20%) or symptomatic: Chest drain (tube thoracostomy in 5th ICS, AAL)
• Open: Seal wound with 3-sided occlusive dressing, then chest drain
• Tension: Immediate needle decompression, then chest drain

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QUESTION: Flail Chest

Definition:

Pathophysiology:

• Paradoxical motion impairs ventilation
• Underlying pulmonary contusion is the main cause of hypoxia (not just the mechanical flap)

Clinical Features:

• Paradoxical chest wall movement (seen on examination)
• Severe pain, dyspnoea
• Crepitus over fracture sites
• Hypoxia, respiratory failure

Management:

• Analgesia (most important - epidural, intercostal nerve blocks, IV opioids) to enable deep breathing
• Physiotherapy, deep breathing exercises
• Supplemental O2
• Mechanical ventilation with PEEP if respiratory failure develops
• Internal fixation of ribs in severe cases

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QUESTION: Complications of Hernia

• Irreducibility (Incarceration)
• Obstruction (bowel obstruction in sac)
• Strangulation (emergency: ischaemic bowel)
• Hydrocele (in children with patent processus vaginalis)
• Inflammation/infection
• Maydl's hernia (W hernia) - strangulation of bowel within abdomen while sac contents appear viable
• Richter's hernia - only part of bowel wall in sac; partial strangulation

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QUESTION: SIRS and Sepsis

SIRS (Systemic Inflammatory Response Syndrome):

• Temperature >38°C or <36°C
• Heart rate >90 bpm
• Respiratory rate >20/min or PaCO2 <32 mmHg
• WBC >12,000 or <4,000 or >10% bands

Sepsis (Sepsis-3 Definition, 2016):

• Clinically: SOFA score increase ≥2
• Quick SOFA (qSOFA): ≥2 of: altered mental status, RR ≥22, SBP ≤100

Septic Shock:

Management (Surviving Sepsis Bundle - 1-hour bundle):

• Blood cultures before antibiotics
• Broad-spectrum antibiotics within 1 hour
• 30 mL/kg crystalloid for hypotension or lactate ≥4
• Norepinephrine (noradrenaline) for MAP <65
• Measure lactate; remeasure if initial >2

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QUESTION: Damage Control Resuscitation (DCR)

1. Permissive hypotension (SBP 80-90 mmHg) until surgical haemorrhage control
2. Haemostatic resuscitation: Blood products in balanced ratios (1:1:1 - PRBC:FFP:Platelets)
3. Minimise crystalloid to prevent dilutional coagulopathy, hypothermia, oedema
4. Tranexamic acid within 3 hours of injury (antifibrinolytic)
5. Damage control surgery: Temporary measures (packing, shunts) to control haemorrhage; definitive repair after resuscitation in ICU

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QUESTION: Types of Urinary Incontinence and Management

Management:

• Pelvic floor exercises (Kegel) - effective for stress incontinence
• Bladder retraining - for urge incontinence
• Lifestyle: weight loss, reduce caffeine/alcohol, fluid management
• Incontinence pads

• Urge: Anticholinergics (oxybutynin, tolterodine), beta-3 agonist (mirabegron)
• Stress: Duloxetine (SNRI)
• Overflow (BPH): Alpha-blockers (tamsulosin), 5-alpha reductase inhibitors (finasteride)

• Stress: Mid-urethral sling (TVT - tension-free vaginal tape), colposuspension (Burch)
• Urge resistant to medication: Botox injection into detrusor, neuromodulation (sacral nerve stimulation)
• BPH: TURP (Transurethral resection of prostate)

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QUESTION: Intracranial Haemorrhages

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QUESTION: Types of Blood Groups and Haemolytic Disease of the Newborn

ABO Blood Group System:

Rh System:

• RhD antigen - most important; 85% population is RhD positive
• Rh incompatibility causes haemolytic transfusion reactions and HDN

Haemolytic Disease of the Newborn (HDN):

• Cause: Rh-negative mother, Rh-positive baby; maternal anti-D antibodies cross placenta and destroy fetal RBCs
• First pregnancy: Usually unaffected (sensitization event)
• Subsequent Rh+ pregnancies: Progressive disease

• Anaemia, jaundice (within 24 hours)
• Hepatosplenomegaly
• Hydrops fetalis (severe - ascites, oedema, heart failure - in utero)
• Kernicterus (unconjugated bilirubin deposits in basal ganglia - permanent brain damage)

Indications for Blood Transfusion:

• Hb <7 g/dL (symptomatic anaemia)
• Hb <8 in cardiac patients or elderly
• Acute haemorrhagic shock
• Symptomatic anaemia regardless of Hb
• Pre-operative in elective cases
• Haemoglobin < 10 g/dL in patients requiring surgery

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QUESTION: Common Causes of Blindness and Prevention

Global Causes (WHO):

1. Cataract - most common cause of blindness worldwide; treatable
2. Glaucoma - 2nd most common; largely irreversible
3. Age-related macular degeneration (AMD)
4. Corneal opacity (trachoma, vitamin A deficiency, trauma)
5. Diabetic retinopathy
6. Trachoma (leading infectious cause)
7. Onchocerciasis (river blindness)
8. Vitamin A deficiency (xerophthalmia) - leading cause in developing countries in children

Prevention:

• Cataract: Early detection, cataract surgery programs (NPCB in India)
• Glaucoma: Regular tonometry screening, early IOP-lowering treatment
• Diabetic retinopathy: Glycemic control, annual fundus screening, laser photocoagulation
• Trachoma: "SAFE" strategy - Surgery, Antibiotics (azithromycin), Facial cleanliness, Environment improvement
• Vitamin A deficiency: Supplementation programs, dietary education
• Trauma: Eye protection, safety glasses

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QUESTION: Refractive Errors of Vision

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KEY TOPICS FREQUENCY ANALYSIS (Most Repeated):

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What Was Answered (Summary)

Section A - Trauma & Emergency Surgery

1. Shock - Definition, classification (5 types), ATLS Classes I-IV, full management of hemorrhagic shock
2. Burns - Classification by depth, Wallace Rule of Nines, Parkland formula, airway management, surgical management
3. Tension Pneumothorax - Pathophysiology, clinical features, immediate needle decompression
4. Flail Chest - Paradoxical movement, management with analgesia + ventilation
5. Primary & Secondary Survey (ATLS ABCDE)
6. Damage Control Resuscitation - Permissive hypotension, 1:1:1 blood products, tranexamic acid

Section B - Wound & Soft Tissue

1. Wound Healing - 4 phases, factors affecting healing (local + systemic)
2. Chronic Ulcers - TIME framework, venous/arterial/diabetic/pressure ulcer management
3. Surgical Site Infections - Classification, organisms, prevention, treatment
4. Skin Grafts - SSG vs FTG comparison table, degloving injury
5. Keloid vs Hypertrophic Scar
6. Gas Gangrene - Clostridium, features, treatment (debridement + penicillin + HBO)

Section C - Elective Surgery

1. Hernia - Classification, direct vs indirect inguinal hernia, Lichtenstein mesh repair
2. Incisional Hernia - Risk factors, mesh repair
3. Abdominal Incisions - 9 types with uses, criteria for ideal incision
4. Uterine Prolapse - Degrees, features, pessary/surgical management (Manchester, vaginal hysterectomy)
5. Laparoscopic vs Robotic Surgery - Pros and cons

Section D - ENT & Ophthalmology (included in this paper)

1. Hearing Aids - 7 types (BTE, ITE, CIC, BAHA, Cochlear implant) with indications
2. Conjunctivitis - Bacterial, viral, allergic, gonococcal, trachoma
3. Refractive Errors - Myopia, hypermetropia, astigmatism, presbyopia
4. Blindness - Causes and prevention (SAFE strategy for trachoma)

Section E - Miscellaneous

1. Blood Transfusion Complications - Immediate + delayed + massive transfusion
2. SIRS & Sepsis - Definitions, Sepsis-3, Surviving Sepsis bundle
3. Anaesthesia - General, spinal, epidural, local with complications
4. GCS - Full scoring table
5. Intracranial Haemorrhages - Extradural (biconvex, lucid interval), subdural, SAH, intracerebral
6. Urinary Incontinence - 5 types, conservative/medical/surgical management
7. Haemolytic Disease of Newborn - Rh incompatibility, anti-D prophylaxis
8. Pregnancy Signs by Trimester

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SHOCK - Detailed Explanation

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1. Definition

"A manifestation of the rude unhinging of the machinery of life" - Gross, 1872 (Sabiston Textbook of Surgery)

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2. Classification of Shock

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3. Pathophysiology of Shock

A. Cellular Level

• Anaerobic respiration ceases
• Sodium-potassium ATPase pumps fail - cells swell with sodium and water
• Intracellular lysosomes rupture and release autodigestive enzymes
• Cell lysis occurs - intracellular potassium floods the bloodstream, causing hyperkalaemia
• This cellular injury is reversible early but becomes irreversible with prolonged shock

B. Microvascular Level

• Hypoxia and acidosis activate complement and prime leukocytes
• Generation of oxygen free radicals and cytokine release
• Injury to capillary endothelial cells - they become "leaky"
• Fluid escapes into tissues - tissue oedema forms, worsening cellular hypoxia
• Activation of the coagulation cascade can lead to DIC (Disseminated Intravascular Coagulation)

C. Systemic / Organ Level

• Reduced preload and afterload trigger baroreceptors
• Increased sympathetic activity → catecholamine release (adrenaline, noradrenaline)
• Results in: tachycardia, systemic vasoconstriction (except in septic/distributive shock where vasodilation occurs)

• Decreased renal perfusion → reduced glomerular filtration → oliguria
• Renin-angiotensin-aldosterone axis activated → further vasoconstriction + sodium/water retention

• Vasopressin (ADH) released → vasoconstriction + water reabsorption by collecting ducts
• Cortisol released from adrenal cortex → sensitises vessels to catecholamines, promotes sodium/water retention
• Respiratory compensation: Metabolic acidosis drives increased respiratory rate (tachypnoea) to blow off CO2 and produce compensatory respiratory alkalosis

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4. ATLS Classification of Haemorrhagic Shock (Grades I-IV)

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5. Clinical Stages of Shock

Compensated (Mild) Shock

• Tachycardia, tachypnoea
• Mild reduction in urine output
• Mild anxiety
• Blood pressure maintained (normal), but pulse pressure narrows
• Cool, sweaty peripheries, prolonged capillary refill time
• The body is still fighting - perfusion to skin, muscle, and gut is sacrificed to protect heart and brain

Uncompensated - Moderate Shock

• Compensatory mechanisms begin to fail
• Urine output drops below 0.5 mL/kg/hour
• Blood pressure starts to fall (mild hypotension)
• Increasing tachycardia
• Patient becomes drowsy and confused

Uncompensated - Severe Shock

• Profound hypotension
• Maximal tachycardia, then bradycardia as a preterminal sign
• Patient is comatose or unresponsive
• Anuric (no urine output)
• Labouring respiration
• Peripheries no longer respond to vasopressors
• Death is imminent without intervention

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6. Specific Types - Additional Details

Hypovolaemic / Haemorrhagic Shock

Hypothermia + Coagulopathy + Acidosis Each factor worsens the others in a deadly spiral: bleeding → acidosis and hypothermia → impaired coagulation → more bleeding.

Cardiogenic Shock

• Heart fails as a pump
• Evidence of venous hypertension (JVP raised, pulmonary oedema) alongside signs of low output
• NOT hypovolaemic - the problem is pump failure, NOT volume depletion
• Treating with aggressive fluids can worsen pulmonary oedema

Obstructive Shock

• Mechanical obstruction reduces cardiac filling (preload)
• Tension pneumothorax, tamponade: the heart is compressed externally
• Beck's triad of tamponade: Hypotension + raised JVP + muffled heart sounds
• Treatment is removing the obstruction (needle decompression, pericardiocentesis)

Distributive / Septic Shock

• Peripheral vasodilation causes blood to "pool" in the periphery
• Cardiac output is actually high (hyperdynamic circulation) but tissue extraction is impaired
• Features: warm peripheries, bounding pulse, widened pulse pressure (opposite to hypovolaemic shock)
• Pathogenesis: Microbial substances (endotoxin, LPS) → activate TLRs → massive cytokine release (TNF, IL-1, IL-6) → vasodilation + endothelial damage + coagulation activation → DIC + multi-organ failure
• Mortality: 20-40% despite treatment (Robbins Pathology)

Neurogenic Shock

• Loss of sympathetic vasomotor tone following spinal cord injury (above T6)
• Bradycardia + hypotension (in contrast, hypovolaemic shock causes tachycardia)
• Warm, dry skin (vasodilated, not vasoconstricted)

Anaphylactic Shock

• IgE-mediated hypersensitivity reaction → massive histamine release
• Vasodilation + increased vascular permeability
• Trigger: Bee sting, drug (penicillin, NSAID), food (peanut)
• Adrenaline (epinephrine) is the first-line treatment

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7. Ischaemia-Reperfusion Injury and SIRS

• The acid and potassium load that built up during hypoperfusion floods the circulation
• Causes direct myocardial depression and further vasodilation
• Molecules from dead cells (DAMPs - Damage-Associated Molecular Patterns) activate leukocytes
• Complement, neutrophils, and microvascular thrombi cause injury to distant organs (lungs, kidneys, brain)
• Leads to: ARDS (Acute Respiratory Distress Syndrome), Acute Kidney Injury, cerebral oedema
• This is the basis of Multiple Organ Failure (MOF)

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8. Management of Shock

Universal Principles (All Types)

1. Treat the cause (haemorrhage control, drain pus, fix the heart)
2. Correct hypovolaemia first - give IV fluids before any vasopressor; giving vasopressors to an empty heart is dangerous and depletes myocardial oxygen rapidly
3. Airway and O2 - high-flow oxygen, intubate if GCS <8 or airway at risk
4. IV access - two large-bore (14-16G) peripheral cannulae; short, wide-bore cannulae allow rapid infusion (central lines have too high resistance for rapid resuscitation)

Management of Haemorrhagic Shock

• External: direct pressure, tourniquet, wound packing
• Internal: emergency surgery or angioembolisation
• Haemorrhage control is the single most important step - no amount of resuscitation corrects ongoing bleeding

1. Rapid haemorrhage control (surgical or interventional)
2. Permissive hypotension - allow SBP 80-90 mmHg (MAP ~50 mmHg) until bleeding is controlled; aggressive normalization of BP increases bleeding. Exception: Traumatic Brain Injury (maintain CPP, do not allow hypotension)
3. Avoid dilutional coagulopathy - minimize crystalloid; use blood products instead
4. Haemostatic resuscitation - blood products in a 1:1:1 ratio (packed red cells : fresh frozen plasma : platelets) to mimic whole blood

• Tranexamic acid (TXA): antifibrinolytic; 1g IV over 10 min, then 1g over 8 hours; must be given within 3 hours of injury (after 3 hours, it is harmful)
• Warm all fluids (prevent hypothermia)
• Calcium supplementation (citrate in blood products chelates calcium)
• Type O negative blood for immediate life-threatening haemorrhage while cross-match is awaited

• Urine output: target >0.5 mL/kg/hr (adults); >1 mL/kg/hr (children)
• Lactate clearance (normalize within 24 hours)
• Base deficit correction
• Heart rate and blood pressure normalization

Management of Septic Shock (Surviving Sepsis Bundle - 1-hour bundle)

1. Blood cultures (before antibiotics)
2. Broad-spectrum antibiotics within 1 hour of recognition
3. IV crystalloid 30 mL/kg for hypotension or lactate ≥4 mmol/L within 3 hours
4. Vasopressor (first choice: noradrenaline/norepinephrine) to achieve MAP ≥65 mmHg if fluids insufficient
5. Measure serum lactate; repeat if initial >2 mmol/L
6. Source control: identify and drain/remove focus of infection

Management of Cardiogenic Shock

• Treat underlying cause (reperfusion for MI - thrombolysis or primary PCI)
• Careful fluid challenge (do NOT flood the lungs)
• Inotropes (dobutamine - positive inotrope, reduces afterload)
• Mechanical support: Intra-Aortic Balloon Pump (IABP), LVAD in refractory cases

Management of Obstructive Shock

• Tension pneumothorax: Immediate needle decompression (14G, 2nd ICS, MCL) → chest drain
• Cardiac tamponade: Pericardiocentesis (needle drainage of pericardial fluid)
• Massive PE: Systemic thrombolysis or surgical embolectomy

Management of Anaphylactic Shock

• Adrenaline (epinephrine) 0.5 mg IM (1:1000 solution) immediately - repeated every 5 min
• IV fluids (large volumes)
• Antihistamines (chlorphenamine IV) + hydrocortisone IV (second line)
• Remove trigger
• Secure airway early (angioedema can close airway rapidly)

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9. Type of Fluids in Shock

Colloids have no proven advantage over crystalloids in most studies; they are more expensive and have worse side-effect profiles - Bailey & Love's Surgery

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10. Monitoring the Response to Shock Treatment

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Summary Diagram of Shock

CAUSE (haemorrhage / sepsis / pump failure / obstruction)
        ↓
REDUCED TISSUE PERFUSION
        ↓
CELLULAR HYPOXIA
        ↓
Aerobic → Anaerobic metabolism → Lactic acidosis
        ↓
Na/K pump failure → Cell swelling → Lysosomal rupture → Cell death
        ↓
Endothelial damage → Capillary leak → Tissue oedema
        ↓
Coagulation activation → DIC
Immune activation → Cytokine storm
        ↓
ORGAN FAILURE (Lung-ARDS / Kidney-AKI / Liver / Brain)
        ↓
MULTIPLE ORGAN FAILURE → DEATH (60% mortality)

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