forensic medicine toxicology n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Forensic Medicine & Toxicology. PowerPoint Presentation
Download Presentation
Forensic Medicine & Toxicology.

Loading in 2 Seconds...

play fullscreen
1 / 12

Forensic Medicine & Toxicology. - PowerPoint PPT Presentation


  • 315 Views
  • Uploaded on

Forensic Medicine & Toxicology. By: Dr. Amina Afzal Rao ASPHYXIA. ASPHYXIA. IT IS DEFINED AS INTERFERENCE WITH THE PROCESS OF OXYGENATION IN THE LUNGS. THE ESSENTIAL FEATURE OF ASPHYXIA IS STRUGGLE TO BREATHE AGAINST SOME KIND OF INTEFERENCE WITH RESPIRATION . TYPES OF ASPHYXIA .

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Forensic Medicine & Toxicology.' - yachi


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
forensic medicine toxicology

Forensic Medicine & Toxicology.

By:

Dr. AminaAfzalRao

ASPHYXIA

asphyxia

ASPHYXIA

IT IS DEFINED AS INTERFERENCE WITH THE PROCESS OF OXYGENATION IN THE LUNGS. THE ESSENTIAL FEATURE OF ASPHYXIA IS STRUGGLE TO BREATHE AGAINST SOME KIND OF INTEFERENCE WITH RESPIRATION.

types of asphyxia

TYPES OF ASPHYXIA

1- MECHANICAL OBSTRUCTION

2- PATHOLOGICAL DISEASE

3- TOXIC PRESENCE OF POISONOUS GASES LIKE CARBON MONOXIDE

4- ENVIRONMENTAL VITIATED ATMOSPHERE OF DEEP WELLS

5- IATOROGENIC IN ANAESTHESIA SURGERY

compression of neck causes

COMPRESSION OF NECK CAUSES

-OBSTRUCTION TO BLOOD FLOW

-OBSTRUCTION TO BREATHING

-OBSTRUCTION TO VENOUS BLOOD

RETURN FROM HEAD CAUSES CONGESTION AND HAEMORRHAGES ABOVE THE LEVEL OF CONSTRICTION .

-OBSTRUCTION TO ARTERIAL BLOOD FLOW CAUSES.BLOCKAGE OF CAROTIDARTERIES --------------ANOXIA OF BRAIN AND UNCONSCIOUSNESS.

slide5

-PARTIAL BLOOD FLOW CONTINUES THROUGH VERTEBRAL VESSELS.- PRESSURE ON THE CAROTID SINUS AND VAGUS NERVE MAY PRECIPITATE REFLEX CARDIAL ARREST. -OBSTRUCTION TO THE WINDPIPE CAUSES GENERALIZED OXYGEN DEFICIENCY.

slide6

-LARYNX IS LIFTED UP SO THAT THE TONGUE BLOCKS THE BACK OF THE THROAT.-PRESSURE ON THE LARYNX------ HYOID BONE THYROID CARTILAGE MAY CAUSE THEIR FRACTURES AND INJURIES TO OTHER SOFT TISSUES.

SITES OF FRACTURES -------???

TWO MECHANISMS----DIRECT LATERALCOMPRESSION----AND INDIRECT THROUGH PRESSURE ON THE THYROHYOID LIGAMENT.

effects of pressure on neck

EFFECTS OF PRESSURE ON NECK

-CAROTID SINUS PRESSURE –VAGAL STIMULATION—CARDIAL ARREST.

-CAROTID ARTERY BLOCKAGE– UNCONSCIOUSNESS

-JUGULAR VEIN BLOCKAGE-----CONGESTION AND HAEMORRHAGES

-AIRWAY BLOCKAGE—OXYGEN LACK

physiology of asphyxia

PHYSIOLOGY OF ASPHYXIA

STUDIED BY SWANN AND BRUCER—ON DOGS.

THREE PHASES OF EXTREMELY SHORT DURATION

UNCONSCIOUSNESS OCCURS IN ONE MINUTE FOLLOWED BY DEATH IN ABOUT 3-4 MINUTES.

slide9

PHASE I:

STIMULATION OF RESPIRATION CYANOSIS

PHASE II:

STRUGGLE TO BREATHE DEEP CYANOSIS, ENGORGEMENT OF NECK VEINS– PETECHIAL HAEMORRAGES CONFUSION—

UN CONSCIOUSNESS.

PHASE III:

UNCONSCIOUSNESS– COMA IRREGULAR BREATHING ---SLOW RESPIRATION ---FAILURE---HEART CONTINUES TO BEAT –PUPILS PILATED--

slide10

BIOCHEMISTRY OF FATAL ASPHYXIA

O2 AND CO2 IN BLOOD

-LOWERING OF BLOOD PH-----ACIDIC BSL---,

-EXCHANGE OF SODIUM AND POTTASIUMIONS ACROSS THE CELL MEMBRANE –

DEATH OF CELLS MAY OCCUR DUE TO DEGENERATION.

slide11

PATHOLOGY OF FATAL ASPHYXIA

-CAPILLOVENOUS ENGORGEMENT WITH RISE IN LEVEL OF CO2 INCIRCULATING BLOOD CAUSES

-GENERALIZED CONGESTION

-CYANOSIS

ANOXIA INCREASE PERMEABILITY OF CAPILLARY WALL ---FLUID OUT INTO TISSUE SPACES—AND TRANSUPATION OF PLASMA INTO TISSUE SPACES CAUSES OEDEMA.

slide12

-RUPTURE OF SMALL CAPILLARIES--- PERMEABILITY PRODUCES PETECHIAL HAEMORRHAGES.GENERAL PATHOLOGICAL CHANGES OR ASPHYXIA:-GENERALIZED CYANOSIS -VASCULAR CONGESTION- OEDEMA OF TISSUES /VISCERA -FLUIDITY OF BLOOD