Asphyxia
Kevin L. Erskine, Erica J. Armstrong in Water-Related Death Investigation, 2021
Asphyxia is defined as the interference with the uptake or utilization of oxygen with a subsequent reduction in the oxygen level within the blood, cells, tissues, and organs.1 Loss of consciousness occurs within seconds and may take as long as 13–18 seconds to occur, according to one report of four filmed hangings (two suicides and two autoerotic accidents).2 Respiratory arrest followed by cardiac arrest ensues after several minutes. In fact, the heart will continue to beat, and there will be a pulse for as long as ten minutes after respiratory arrest.1 Death due to asphyxia occurs in one of several ways: Obstruction of the external airway (nose and mouth)Obstruction of the internal airway (oral cavity, larynx, trachea, bronchi, lungs)Compression/occlusion of the blood vessels of the neck (carotid arteries, jugular veins)Severe flexion of the neck or compression of the chest or abdomenImpairment of O2 utilization by the body’s cellsDisplacement of O2 from the ambient environment
Chemical injuries
Jan de Boer, Marcel Dubouloz in Handbook of Disaster Medicine, 2020
Physical asphyxiants are biologically inert gases that produce hypoxaemia and asphyxia by displacing oxygen from air13,21,23. Casualties usually result when individuals are inside or enter an enclosed space (mine, silos, ship holds) where oxygen has been either displaced by an inert gas or depleted by combustion13. Massive gas release from either volcanoes or water lakes can also be a hazard26. Exposure to physical asphyxiants can occur without patient knowledge or physician recognition, these gases being colourless and often odourless, and asphyxiation can occur without direct pulmonary damage23. Symptoms of asphyxia including hyperventilation, sweating and headache will appear when oxygen concentration falls below about 15 percent. Memory loss, incoordination and stupor are seen with levels below 10 percent. Loss of consciousness followed by death will occur when oxygen concentration falls below 6 to 8 percent13,21,23. Representative physical asphyxiants are carbon dioxide, nitrogen, methane, propane and nitrous oxide.
Birth Injuries, Neonatal
Tony Hollingworth in Differential Diagnosis in Obstetrics and Gynaecology: An A-Z, 2015
Hypoxic ischaemic encephalopathy (HIE) is the term used to describe hypoxic injury to the neonatal brain. The incidence of HIE is estimated at 1 to 8 per 1000 live births in a developed country. The incidence is much higher in developing countries, however (e.g., 26.2 per 1000 live births in a Nigerian study).7 It is difficult to estimate the incidence accurately owing to the lack of universally agreed definitions and selection bias in referral centres. In terms of mortality rates, birth asphyxia accounted for 23 per cent of the 4 million neonatal deaths (during the first 28 days of life) worldwide in 2000.8 The risk of dying due to birth asphyxia is 8 times higher for babies in a country with a high neonatal mortality rate. The risk of death or severe neurological impairment following hypoxia-ischaemia is estimated at about 1 per 1000 live births in a resource-rich country, and 5–10 per 1000 live birth in a resource-poor country.9
Predicting asphyxia in term fetus
Published in Journal of Obstetrics and Gynaecology, 2023
Alev Esercan, İsmail Demir
There were two groups as group 1 (asphyxia group) and group 2 as control group. Group 2, as the control group, were selected retrospectively with simple random sampling from the babies who were followed up with their mothers after birth as term, healthy babies without any anomaly, and the demographic characteristics of the mothers, baby’s gender, birth weight, type of birth and presence of risk factors before birth were similar to group 1 and the maternal hematological parameters before the birth were recorded. Our study was a retrospective study consisting of asphyxia and control groups. Group 1 consisted of asphyxia fetuses selected according to the study criteria from the neonatal intensive care unit as stage 3 HIE according to (Mrelashvili et al.2020) Sarnat and Sarnat classification, while group 2, the control group, term babies selected according to the study criteria from the mother side, healthy babies without a fetal anomaly.
Clinical utility of chromosomal microarray analysis and whole exome sequencing in foetuses with oligohydramnios
Published in Annals of Medicine, 2023
Xiaomei Shi, Hongke Ding, Chen Li, Ling Liu, LiHua Yu, Juan Zhu, Jing Wu
In addition, we found a homozygous point variation c.199-10T > G in the SLC25A20 gene in a fetus with severe oligohydramnios. Mutations in this gene cause CACTD. CACTD is a rare autosomal recessive metabolic disorder of long-chain fatty acid oxidation. The clinical manifestations are mainly neuropsychiatric abnormalities, cardiomyopathy, arrhythmias, skeletal muscle damage and liver dysfunction, renal tubular fatty changes, etc. Some patients have symptoms such as asphyxia, dyspnoea and oliguria [25]. Our study is the first study to evaluate the prenatal phenotype of foetus diagnosed with CACTD. The results identify a further expansion of the prenatal presentation of CACTD and contribute to the genetic diagnosis and counselling of this disorder.
Fatal self-poisoning with amitriptyline: a case report and brief review of literature
Published in Journal of Substance Use, 2023
Qing Gao, Bin Lv, Weisheng Huang, Tianying Sun, Hongmei Dong
A 27-year-old woman was found dead in an undisturbed bed in a dormitory by her roommate. A total of 3 empty amitriptyline bottles were found in the trash can. No evidence of struggle was reported at the death scene. According to the description from her family, the decedent had no history of illness or medication except depression with long-term amitriptyline use. The blood was collected by cardiac puncture through the chest wall the day the body was found. The body was frozen (−20°C) until the systematic autopsy was carried out five days after death. No signs of apparent injury and mechanical asphyxia were noted. On internal examination, no lethal anatomic changes such as structural heart disease were existed. A total of 10 ml of thick liquid with white granular substance was found in her stomach, and spotty hemorrhages on the gastric mucosa were observed. The following microscopic examination revealed brain swelling, focal pulmonary hemorrhages and edema. The widespread congestion was observed in multiple organs especially brain and lungs. The cardiac blood was analyzed by a gas chromatography-mass spectrometry method, which revealed a blood amitriptyline level of 8.8 μg/ml. The analysis demonstrated the absence of other toxicants and/or drugs in blood. The possibility of death from injury, mechanical asphyxia and/or lethal anatomical changes could be ruled out. In addition, the blood amitriptyline level could not support an overdose accident since the concentration was much higher than that used for therapeutic applications (0.12–0.25 μg/ml; Linder & Keck, 1998). Thus, amitriptyline intoxication should be attributed to intentional suicide in this case.
Related Knowledge Centers
- Acute Respiratory Distress Syndrome
- Airway Obstruction
- Asthma
- Breathing
- Hemoglobin
- Drug Overdose
- Body
- Laryngospasm
- Cigarette
- Effect of Spaceflight On The Human Body