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APLASTIC ANAEMIA

An 18 year old adult presents to your office with complaints of fever, fatigue and lethargy for 1 week duration. He also gives you a history of fever, sore throat and numerous swellings around his neck 3 weeks back and it resolved spontaneously. He has no other complaints. On examination, his vitals are:     P- 100bpm, BP- 110/80 mmHg, temp.- 1000F, RR- 20/min. On general examination, you observe purpuric and ecchymotic rashes on the anterior of shin, thigh and trunk. His liver and spleen are not palpable. How will you proceed with the management of this case?

  • Pancytopenia with hypocellularity (aplasia) of the bone marrow; there are no leukaemic, cancerous or other abnormal cells in the peripheral blood or bone marrow. 
  •  inherited and acquired.
  • Reduction in the number of pluripotential stem cells
  • Failure of only one cell line e.g. RBCs results  in pure red cell aplasia. 
  •  Myelodysplasia, paroxysmal nocturnal haemoglobinuria (PNH) or acute myeloblastic leukaemia occurs in some cases due to an abnormal clone of haemopoietic cells.
  • Activated cytotoxic T cells in blood and bone marrow are responsible for the bone marrow failure.
Causes of aplastic anaemia

Primary
  • Congenital, e.g. Fanconi's anaemia 
  • Idiopathic acquired (67% of cases) 
Secondary
  • Chemicals, e.g. benzene 
  • Drugs: 
  • chemotherapeutic 
  • idiosyncratic reactions 
  • Insecticides
  • Ionizing radiation 
  • Infections: 
  • viral, e.g. hepatitis, EBV, HIV, parvovirus 
  • other, e.g. tuberculosis 
  • Paroxysmal nocturnal haemoglobinuria 
  • Miscellaneous, e.g. pregnancy 
  • Busulfan ,doxorubicin, chloramphenicol, gold, carbimazole, chlorpromazine, phenytoin, tolbutamide, non-steroidal anti-inflammatory agents, 
  •  Gene mutations e.g. the telomerase RNA component, in one third of aplastic anaemias. 
  • Fanconi's anaemia ,inherited as an autosomal recessive, is associated with skeletal, renal and central nervous system abnormalities, ages of 5 and 10 years. 
Clinical features
  • Anaemia, bleeding and infection(oral). 
  • Bruising with minimal trauma or blood blisters in the mouth. 
  • Physical findings include ecchymoses, bleeding gums and epistaxis. 
  • Lymphadenopathy and hepatosplenomegaly are rare.
Investigations
  • Peripheral smear
  • pancytopenia 
  • the virtual absence of reticulocytes 
  • a hypocellular or aplastic bone marrow with increased fat spaces
Causes of pancytopenia
  • Aplastic anaemia
  • Drugs 
  • Megaloblastic anaemia 
  • Bone marrow infiltration or replacement   
  • Hodgkin's and non-Hodgkin's lymphoma
  • Acute leukaemia   
  • Myeloma
  • Myelofibrosis 
  • Hypersplenism 
  • Systemic lupus erythematosus
  • Disseminated tuberculosis 
  • Paroxysmal nocturnal haemoglobinuria 
  • Overwhelming sepsis
Treatment and prognosis

Supportive care, specific treatment
Treatment of infection – if any.
Immediate institution of broad-spectrum parenteral antibiotics in neutropenic patient – prophylactic in all cases.
Supportive care: transfusions of red cells and platelets

A bad prognosis (i.e. severe aplastic anaemia) if two of the following three features:
neutrophil count of less than 0.5 × 109/L
platelet count of less than 20 × 109/L
corrected reticulocyte count less than 1% (or absolute reticulocyte count less than 60,000/L).
Survival of patients  is about 20% at 1 year after diagnosis with  supportive care;

Suspect exposures to drugs or chemicals should be discontinued;

HEMATOPOIETIC STEM CELL TRANSPLANTATION

Treatment of choice for patients under 40 years of age who have an HLA-identical sibling donor, which gives a 75-90% chance of long-term survival, restores the blood count to normal.
Immunosuppressive therapy  for patients without HLA-matched siblings and over the age of 40 years; antilymphocyte globulin (ALG) and ciclosporin in combination(60-80%).

Androgens (e.g. oxymethalone)
Steroids   are  used in children with congenital pure red cell aplasia (Diamond-Blackfan syndrome).
Adult pure red cell aplasia is associated with a thymoma in 30% of cases and thymectomy may induce a remission.

Mendelian Disorders List

Autosomal recessive disorders 

  • Sickle cell disease
  • Cystic fibrosis 
  • alpha-1 antitrypsin deficiency
  • 21-hydroxylase deficiency
  • Wilson's disease
  • Thalassemia 


Autosomal dominant disorders

  • Hereditary angioedema(C1 esterase inhibitor deficiency)
  • Hereditary spherocytosis
  • Familial Hypercholestrolemia
  • Neurofibromatosis 
  • Huntington's disease
  • Osteogenesis imperfecta
  • Achondroplasia
  • Tuberous sclerosis


X-linked recessive disorders

  • Glucose-6-phosphate dehydrogenase deficiency
  • Duchenne's muscular dystrophy
  • Hemophilia A
  • Hunter's syndrome
  • Fragile X syndrome
  • Lesch-Nyhan syndrome
  • Testicular feminization
  • Chronic granulomatous disease
  • Bruton's agammaglobulinemia 


X-linked dominant disorders

  • Vitamin D-resistant rickets
  • Alport's syndrome

DEGREES OF BURN AND MANAGEMENT

  • BURNS  &  SCALDS
  • ELECTRICAL BURNS
  • CHEMICAL BURNS
  • RADIATION
  • LIGHTENING


PRE-HOSPITAL CARE
  • Remove patient from source
  • Extinguish burning clothes
  • Careful with electric source
  • CPR
  • If hospital is 30- 45 min away try to start IV
  • Cold soaks ↓ pain but ↓ heat, so avoid hypothermia
  • Cover the areas with clean sheets
  • 100% O2  if suspected CO poisoning
  • Check for respiratory burns


IN EMERGENCY
  • ABC
  • Assess the percentage and degree of burn
  • Start IV line and infuse Ringer’s Lactate and calculate the fluid requirement
  • Take patient’s weight                         
  • Catheterize
  • Oxygen if required
  • TT  injection
  • Morphine 
  • Wound care- clean with saline and apply 1%silver sulphadiazene
  • No role  of prophylactic antibiotic


ASSESSMENT OF BURNS

Wallace’s Rule of Nine-in adults each upper extremity, and the head and neck are 9% TBSA, lower extremities, anterior and posterior trunk each are 18% while genitalia and perineum forms 1% of TBSA
Infant head is 18 % and lower limb is 14%, for each year after one year 1% to be taken off the head and neck area and added to the lower limbcs
Patient’s palm as 1 %

FLUID RESUSCITATION

  • Modified Parkland’s formula
  • 4ml X   Body weight X % Burns ( 50 % ) 
  • Ringer’s lactate to be given. 50% in first eight hours from the time of burns
  • 50% in next 16 hours
  • Response- 1ml/Kg/hr urine output. 50-70ml in adults


DEGREES OF BURN

FIRST  DEGREE
  • Sunlight exposure or burn by hot tea cup
  • Injury confined to epidermis
  • Red and dry
  • Very painful
  • Heals in 3-6 days without scarring
  • Not included while calculating fluid requirement for burns



SECOND DEGREE SUPERFICIAL
  • Hot liquid or flash flame
  • Pink or mottled red in appearance
  • Blisters or bulla, soft and moist
  • Painful
  • 7-10 days to heal and may have hypo or hyper pigmented areas



SECOND DEGREE DEEP
  • Chalky white
  • Soft and moist 
  • Sensation is obtunded
  • More than 21 days to heal
  • Heals with lot of scarring and contractures



THIRD DEGREE BURN
  • Prolonged exposure or electric burn
  • Dry and parchment like
  • Translucent, can see fat and thrombosed veins
  • No sensation
  • Needs debridement of eschar and skin grafting



MAJOR BURNS

Partial thickness greater than 25%
Partial or full thickness burns of face, hands, genitalia and feet
Third degree burn greater than 10% area
Burns complicated by
Respiratory tract injury
Major soft tissue injury
Fractures
Electrical burns

MODERATE

Second degree burns 15-25%
Third degree less than 10% except hands, face and feet

MINOR

Second degree less than 15 %
Third degree less than 2 %

PATHOPHYSIOLOGY

Jackson’s three zones
  • Zone of coagulation
  • Zone of stasis
  • Zone of hyperaemia

CVS- shift of fluid, ↓cardiac output, greater than 25 % burn even non burned tissue also swell

LUNGS- hyperventilation, ↓ protein, poor lung function
GIT- ileus, mucosal ischaemia, curling’s ulcers, translocation of bacteria
RENAL- renin- angiotensin- aldosterone system activated, ↓ urine output, ATN
IMMUNE SYSTEM- destruction of barrier, depression of cellular immunity
BODY TEMP. – loss of protective mechanism, heat loss & hypothermia, ↑ spike after dressing due to pyrogens such as interleukin-1

WOUND CARE

Clean with surgical detergent or clean water shower or water tank and twice daily dressing with 1% SSD

BIOLOGICAL  DRESSINGS

Allograft, skin substitutes- collagen amino acid films
Amnion, porcine skin, integra, homograft, Burn mesh


Local care

Dressings
Open- neck, hand, 
occlusive,
Biological
Early surgical excision and grafting
Tangential excision

ANTIBACTERIALS

Sulfonamide
Thick application
Twice daily
Good penetration

Silver Nitrate
Bacteriostatic
Black discoloration
Thick pads required
Leaching of Na, K, Cl, Mg and Ca
Poor penetration

Silve sulphadizene
1968 Charles Fox
Silver nitrate and acid sulphadizene
Bacteriostatic
Good penetration
Gentamicin
2.2% Cerium nitrate and SSD

NUTRITION

Metabolic needs ↑ by two to three fold
CURARIE  FORMULA
25KCal  x  Body weight + 40KCal x  % Burns
Supplement Vit C, zinc and B complex 

INFECTION ( Clinical)

Conversion of 2o - 3o
Focal dark brown or black discoloration
Degeneration of wound with neoeschar
Rapid separation of eschar
Hemorrhagic discoloration of subeschar fat
Erythematous wound margin
Metastatic septic lesion in unburned tissue


INFECTION ( Histological)

Organism in unburned tissue
Hemorrhage in unburned tissue
↑ inflammatory reaction in adjacent tissue
Small vessel thrombosis or ischaemic necrosis of unburned tissue
Perineural and intralymphatic migration of organism
Vasculitis and perivascular cuffing of organisms

Other septic complications
  • Pneumonia
  • Sup. Thrombophlebitis
  • Endocarditis
  • Sepsis


Verduria

FASCIOTOMY, ESCHAROTOMY, ESCHARECTOMY, SKIN GRAFTING

Eschar is the burnt dead skin
Fascia is the deeper tissue covering the muscles
Burn wound excision
↓ hospital stay
↓ sepsis ( greater than 30% increased chance of sepsis)
Better cover, early healing, ↓ scar
Rapid restoration of function

ESCHAROTOMY
  • If vascular or respiratory compromise due to thick constricting eschar
  • Escharotomy done at the neutral lines. 
  • If no improvement do fasciotomy( mostly in electric burns) 



ESCHARECTOMY

Surgical removal of eschar 
Early- done in 7- 12 days
Late- separates after two weeks.
Prepares bed for early grafting
Tangential excision and grafting
In second degree deep burns
Done on 2nd to 5th day
After 7 days it softens
Not more than 20% in one sitting


SEQUENTIAL EXCISION
  • Done in deep second degree and third degree burns
  • Blood loss  5% area one unit blood required
  • Eschar sequentially removed with a guarded knife and grafted
SKIN GRAFTING

Pinch, mesh, stamp, sheet
Thin, Intermediate, Thick ( Split thickness graft)
Full thickness graft
Priority areas
face, hands, axilla, cubital and popliteal fossa
Autograft, homograft, heterograft


    ELECTRIC BURNS
    • Low voltage ( greater than 1000 volts )
    • High voltage ( less than 1000 volts )
    • Conversion of electrical energy to heat is governed by Ohm’s law
    • C= V/R current in amperes
    • Joule’s Law- J= C2RT relation between current and heat production
    • Bone offers the most resistance
    • Current takes the shortest path
    • Body acts as volume conductor
    • Arc injury is very deep
    • “no release” phenomenon
    • Skeletal injury due to fall.
    • Cardiac- arrest, VT, AF, SVT, RBBB
    • Renal- ARF, Myoglobinuria
    • CNS- convulsions, coma, paraplegia
    • Abdomen- Splenic injury
    MANAGEMENT

    General
    Deep burns- maintain urine output of 2ml/kg/hr
    Mannitol 12.5 gm/hour
    50ml 7.5% NaHCO3 ( 45 mEq)
    Cardiac monitoring ( CPK-MB) 


    SUTURE MATERIALS AND SUTURING TECHNIQUE

    Materials required
    • Suture set containing bowl, needle holder, scissors, tissue forceps
    • Disposable syringe(5-10ml)
    • Local anesthetic (xylocaine 2% with or without adrenaline
    • Suture material
    • Povidone iodine
    • Sterile gauze piece
    • Sterile gloves
    • Sterile eye towel

    Skin suturing
    • Wound should be closed with minimum tension
    • Edges of skin should gape slightly to allow swelling due to inflammation. If wound is closed tightly edge  necrosis may occur
    • Needle should be held at a point 2/3rd  from tip of  the needle
    • Needles are inserted at right angles to the skin for simple suture using a supination pronation movement of the wrist
    • Entry and exit points should be nearly the same distance from the wound edge as the thickness of skin being closed

    • The edge of wound is gently lifted with forceps while the needle is inserted
    • Edges should be everted slightly. If suture is enters and exits from the skin at an acute angle wound may become inverted with poor healing 
    • As the suture is tightened, knot should be drawn to one side to facilitate suture removal
    • When a non-absorbable suture is to be removed, it is cut immediately beneath the knot and pulled out by knot. This results in contaminated part of suture  material being lifted away without  being drawn through the wound

    • The ends of knot should be left long enough to be easy to grasp while removing yet not too long to get tangled with nearby structures
    • As a general rule each suture should be separated by a gap that is twice the  thickness of skin
    • Stay sutures should be applied in wounds with curves or zigzags for correct orientation
    • Non absorbable skin sutures should be removed when wound has healed to prevent scarring, infection and irritation. It is removed from face after 3-5 days, 5-7 days from scalp, 7 days from back, 10 days from abdomen and 10-14 days from limbs
    • Any suture with pus or signs of infections should be removed immediately

    Types of wound closure

    Simple interrupted– most commonly used, good for shallow wounds without edge tension

    Continuous (running sutures)– good for long wounds with minimal tension

    Locking continuous - useful in wounds under moderate tension or in those requiring additional hemostasis because of oozing from the skin edges

    Subcuticular – good for cosmetic results

    Vertical mattress – useful in maximizing wound eversion, reducing dead space, and minimizing tension across the wound

    Horizontal mattress – good for fragile skin and high tension wounds

    Tension suture – for support in wound under very high tension



    Classification of suture material

    Non-absorbable

    • Not biodegradable and permanent
    • Tensile strength lasts for more than 60 days
    • Nylon
    • Prolene(polypropylene)
    • Stainless steel
    • Silk (natural, can break down over years)


    Absorbable

    Degraded via inflammatory response

    • Vicryl (polyglactin)
    • PDS (polydioxanone)
    • Chromic Cat gut (natural)

    Natural Suture

    Biological
    Cause inflammatory reaction

    • Silk (from silkworm fibers)
    • Catgut (connective from cow or sheep)
    • Chromic catgut

    Synthetic

    Synthetic polymers
     Do not cause intense inflammatory reaction

    •  Vicryl
    •  PDS
    •  Prolene
    •  Nylon

    Monofilament
    • Single strand of suture material
    • Minimal tissue trauma
    • Smooth tying but more knots needed
    • Harder to handle due to memory
    • Less chance of infection
    • Examples: nylon, prolene, PDS


    Multifilament (braided)
    • Fibers are braided or twisted together
    • More tissue resistance
    • Easier to handle
    • Fewer knots needed
    • More chances of infection
    • Examples: vicryl, silk, chromic catgut

    Suture Selection

    • Do not use dyed sutures on the skin
    • Use monofilament on the skin as multifilament harbor BACTERIA
    • Non-absorbable cause less scarring but must be removed
    • Location and layer, patient factors, strength, healing, site and availability 
    • Silk and synthetic sutures are employed most often
    • Gut sutures are used only when retrieval is difficult.

    Other materials

    Metal sutures, clips and staples are available