Cell Injury, Cell Death, and Autopsy- PRELIMS L2

CELLULAR INJURY

• Results when cells are stressed so severely that they are no longer able to adapt.

• When cells are exposed to inherently damaging agents or suffer from intrinsic abnormalities.

CAUSES OF CELLULAR INJURY

1. Oxygen deprivation

2. Reduced blood flow

3. Physical agent

4. Chemical agents and drugs

5. Infectious agent

6. Immunologic reaction

7. Genetic derangement

8. Lack of nutrition

REVERSIBLE CELL INJURY

Cell may return to its normal and functional state

CELLULAR DEATH

(irreversible) – apoptosis or necrosis

REVERSIBLE INJURY

• CELLULAR SWELLING/ HYDROPIC CHANGE/ VACOULAR DEGENERATION

• FATTY CHANGE

CELLULAR SWELLING/ HYDROPIC CHANGE/ VACOULAR DEGENERATION

Cells are incapable of maintaining ionic and fluid homoeostasis failure of energy-dependent ion pumps which results in swelling of the cell

FATTY CHANGE

• Occurs in hypoxic injury

• Manifested as lipid vacuoles in the cytoplasm

TYPES OF CELL DEATH

• Apoptosis

• Necrosis

APOPTOSIS

• Is a form of cell death that is generally triggered by normal, healthy processes in the body.

• Apoptosis, which can also occur as a defense mechanism during healing processes, is almost always normal and beneficial to an organism.

NECROSIS

• Is cell death that is triggered by external factors or disease, such as trauma or infection.

• Necrosis is always abnormal and harmful.

• It is considered an "unprogrammed" (unnatural) cell death process at this time

TYPE OF NECROSIS

“CoLiG C. FaG F“

1. Coagulation Necrosis

2. Liquefaction Necrosis

3. Gangrenous Necrosis

4. Caseous Necrosis

5. Fat Necrosis

6. Gaseous Necrosis

7. Fibrinoid Necrosis

COAGULATION NECROSIS

• The architecture of the dead tissues is preserved

• Denatures not only the proteins but also the intracellular enzymes

• This type is seen most often in the heart after an infarction, as well as in kidneys and spleen

LIQUEFACTION NECROSIS

• Transformation of the tissues into liquid viscous mass

• Seen in focal bacteria/ fungal infection

• Accumulation of leukocytes and liberation of enzymes- pus

GANGRENOUS NECROSIS

• Refers to massive death of the tissue caused by a combination of ischemia and superimposed by bacterial infection

  
  Applied to a limb:

  • Coagulative→ arterial occlusion

  • Liquefactive→ venous occlusion

CASEOUS NECROSIS

• Conversion of destroyed cells into granular, friable mass made up of a mixture of coagulated protein and fats.

• Fragmented or lysed cells enclosed in an inflammatory border- granuloma

FAT NECROSIS

• Focal area of fat destruction

• Release of pancreatic lipase into the pancreas and peritoneal cavity

• Acute Pancreatitis

GASEOUS NECROSIS

This combination of liquefactive and coagulative necrosis is caused by dead cells that are not completely digested by macrophages; they leave a granular residue that impedes circulation.

FIBRINOID NECROSIS

Fibrin is the main reason for this type of necrosis to happen.

BIOPSY

Removal of cells or tissues for examination from a living subject to determine the presence or extent of a disease

EXCISIONAL BIOPSY

When an entire lump or suspicious area is removed

INCISIONAL/ CORE BIOPSY

When only a sample of tissue is removed with preservation of the histological architecture of the tissue’s cell

FINE NEEDLE ASPIRATION BIOPSY

When a sample of tissue or fluid is removed with a needle.

OTHER TYPES OF BIOPSIES

• Punch Biopsy

• Shave Biopsy

• Curettage Biopsy

PUNCH BIOPSY

A punch biopsy is done with a circular blade ranging in size from 1 mm to 8 mm. The blade, which is attached to a pencil-like handle, is rotated down through the epidermis and dermis, and into the subcutaneous fat, producing a cylindrical core of tissue.

SHAVE BIOPSY

A shave biopsy is done with either a small scalpel blade or a curved razor blade.

CURETTAGE BIOPSY

A curettage biopsy can be done on the surface of tumors or on small epidermal lesions with minimal to no topical anaesthetic using a round curette blade.

CURETTE

A surgical instrument that has a scoop, ring, or loop at the tip.

NECROPSY; AUTOPSY

• After death examination of the body and dissection of its internal organs to confirm or determine the cause of death.

• Autopsy can uncover the existence of disease not detected during life, determine the extent of injuries may have contributed to a person’s death.

PRELIMINARIES FOR PME

1. Written consent from the next of kin-abide by the extent or restrictions allowed

2. Death certificate (blue form)

3. Medical abstract / Clinical data

4. Medico Legal Clearance

PME IS PERMITTED W/O CONSENT IN THE FOLLOWING CIRCUMSTANCES

1. When it is ordered by the police or coroner

2. When it is necessary to complete the death certificate

3. When the deceased himself has given consent before he died

4. Deceased military personnel who dies in active/training duty or military service

THE CORONER HAS AUTHORITY IN THE FOLLOWING CASES

1. All natural deaths occurring in the hospital within 24 hrs. of admission, unless the case was attended by a private physician within 36 hours of death

2. Newborns in the first 24 hours of life

3. All injury cases, old or recent

4. All deaths due to unknown cases

5. All deaths due to suspicious cases

6. All abortion cases, whether self-induced or otherwise

7. All violent deaths

8. All accidental deaths

9. All sudden deaths

10. All cases without medical attendance within 36 hours prior to the hour of death

11. All deaths due to drowning, hanging or strangulation

12. All deaths due to shooting, stab wounds, burns, electricity, lightning, tetanus, etc.

13. All homicide

14. All suicide

15. All cases in which there is suspicion of poisoning

16. Stillborns

17. Prematures

POSTMORTEM CHANGES

1. Algor Mortis

2. Rigor Mortis

3. Livor Mortis or Postmortem Hypostasis

4. Postmortem clotting of blood

5. Discoloration of tissues

6. Putrefaction- decaying/ rotting

ALGOR MORTIS

• At room temp.: 2-2.5°F/hr – 1st hour

• As a rule, the body cools at 1.5°F/hr (50% of cases)

• Not reliable indicator

• 12 hours: 1.5-2°F/hr

• 12-18 hours: 1°F/hr

RIGOR MORTIS

• Rigidity of the body due to hardening of the skeletal muscles caused by a series of physicochemical events after death

• Lacks ATP regeneration

• Sets within 2 hrs. after death (head & neck)

• Complete with 12 hrs.

• 3-4 days longevity

LIVOR MORTIS OR POSTMORTEM HYPOSTASIS

• Becomes evident as early as 20 min. after death

• Blood supply will gravitate to the skin which become toneless and dilate

FOUR MAIN TYPES OF AUTOPSIES

1. Medico-Legal Autopsy or Forensic or Coroner's autopsy

2. Clinical or Pathological autopsy

3. Anatomical or Academic Autopsy

4. Virtual or Medical Imaging Autopsies or Virtopsy

MEDICO- LEGAL AUTOPSY OR FORENSIC OR CORONER’S AUTOPSY

Death is classified into one of five headings: (HANSU)

a. natural

b. accident

c. homicide

d. suicide

e. undetermined

• cause and manner of death

CLINICAL OF PATHOLOGICAL AUTOPSY

• Is performed to diagnose a particular disease

• It aims to determine, clarify, or confirm medical diagnoses that remained unknown/ unclear prior to the patient's death

ANATOMICAL OF ACADEMIC AUTOPSY

Is performed by students of anatomy for study only.

VIRTUAL OR MEDICAL IMAGING AUTOPSIES OR VIRTOPSY

Is performed utilizing imaging technology only, primarily magnetic resonance imaging (MRI) and Computed Tomography (CT)

EXTERNAL EXAMINATION

• Photograph

• Note the clothing, position

• Evidence-residues- uses UV Light

• Samples of hair, nails.

• After external evidence is collected-

• Clean the body, weighed, measured

• General description of the body as regards ethnicity, sex, age, hair color and length, eye color and other distinguishing features

• Handheld voice recorder

INTERNAL EXAMINATION

1. Y shaped incision can be made starting at the top of each shoulder and running down the front of the chest, meeting at the lower point of the sternum.

2. T-Shaped Incision made from the tips of both shoulders in a horizontal line across the region of the collar bones to meet at the sternum in the middle

3. Single Vertical Cut is made from the middle of the neck

KINDS OF AUTOPSIES

1. Autopsy of Virchow

2. Autopsy of Letulle

3. Autopsy of Rokitansky

4. Autopsy of Ghon

AUTOPSY OF VIRCHOW

Where each organ is taken out one by one

GOOD FOR: Demonstrating pathological change in individual organs

ADVANTAGE OF VIRCHOW

• Simple to perform

• Systematic examination

DISADVANTAGE OF VIRCHOW

Destroys anatomic relationship

AUTOPSY OF LETULLE

Where organs are taken out En bloc

(En bloc- all together in a united group, En masse- in a mass; all together; as a group)

ADVANTAGE OF LETULLE

Preserving vascular supply

AUTOPSY OF ROKITANSKY

Where organs are examined in- situ (in placed)

ADVANTAGE OF ROKITANSKY

ADVANTAGE:

• Practical for single examiner

• Good preservation of anatomic structures in-situ.

• Good preservation of pathologic anatomic relationships

• Subsequent autopsies can be easily performed on the same body

DISADVANTAGE OF ROKITANSKY

• Requires a certain degree of expertise and skill

• Thorough examination may not be possible

• If cause of death is determined, less attention is paid to other

• Pathologies

AUTOPSY OF GHON

There organs are taken out in three separate blocks

A. Cervical region

B. Abdominal region

C. Urogenital region

ADVANTAGES OF GHON

• Anatomic relationships are preserved without a bulky mass of organs

• Systems examined within their structural integrity

• Good observation of pathologic lesions

ADVANTAGES OF GHON

• Not ideal for multiple organ involvement

• Requires skill and time