An unusual case of death: suffocation caused by leaves of common ivy (Hedera helix). Detection of hederacoside C, alpha-hederin, and hederagenin by LC-EI/MS-MS.
(41/274)
We report one fatal case of asphyxia caused by leaves of common ivy. Macroscopic examination of the corpse during the autopsy disclosed an incredible quantity of leaves of Hedera helix in the mouth and throat of the decedent. In order to rule out the possibility of poisoning by the toxic saponins contained in the plant, we have developed an efficient LC-EI/MS-MS assay of hederacoside C, alppha-hederin, and hederagenin in biological fluids and plant material. Sample cleanup involved solid-phase extraction of the toxins on C18 cartridges followed by LC analysis under reversed-phase conditions in the gradient elution mode. Solute identification was performed using full scan MS-MS spectrum of the analytes. Oleandrine was used as internal standard. Under these conditions, saponins in powdered dried leaves of Hedera helix were measured at a concentration of 21.83 mg/g for hederacoside C, 0.41 mg/g for alpha-hederin and 0.02 mg/g for hederagenin. No toxin was detected in cardiac blood, femoral blood, or urine of the deceased, but hederacoside C was quantitated at 857 ng/mL in the gastric juice. These findings led us to conclude that the man committed suicide and that the death was caused by suffocation by leaves of common ivy. (+info)
Strangulation injuries.
(42/274)
Strangulation accounts for 10% of all violent deaths in the United States. Many people who are strangled survive. These survivors may have minimal visible external findings. Because of the slowly compressive nature of the forces involved in strangulation, clinicians should be aware of the potential for significant complications including laryngeal fractures, upper airway edema, and vocal cord immobility. Survivors are most often assaulted during an incident of intimate partner violence or sexual assault, and need to be specifically asked if they were strangled. Many survivors of strangulation will not volunteer this information. Accurate documentation in the medical chart is essential to substantiate a survivor's account of the incident. Medical providers are a significant community resource with the responsibility to provide expert information to patients and other systems working with survivors of strangulation. This case study reviews a strangulation victim who exhibited some classic findings. (+info)
Cerebral metabolism during cord occlusion and hypoxia in the fetal sheep: a novel method of continuous measurement based on heat production.
(43/274)
This study was undertaken to validate a new method of measuring cerebral metabolic rate in the fetal sheep based on heat production in a local region of the brain. Heat production was compared to oxygen use in 20 near-term fetuses during basal conditions, moderate hypoxia and cord occlusion. Thermocouples were placed to measure core and brain temperature and a composite probe placed in the parietal cortex to measure changes in cortical blood flow (CBF) using laser Doppler flowmetry and tissue PO2 using fluorescent decay. Catheters were inserted in a brachiocephalic artery and sagittal sinus for blood sampling. With moderate hypoxia, induced by administering 10-12 % oxygen to the ewes, fetal arterial PO2 declined from 23 +/- 1 to 11 +/- 1 Torr and brain tissue PO2 fell from 7.6+/- 0.7 to a nadir of 0.8 +/- 0.4 Torr, while CBF increased to 139 +/- 5 % of baseline. Cortical heat production, calculated as the product of CBF, the temperature gain from artery to brain tissue, and the specific heat of blood, decreased by 45 +/- 11 % in parallel to similar declines in oxygen uptake. With severe asphyxia induced by complete cord occlusion for 10 min, fetal arterial PO2 declined from 23 +/- 1 to 9 +/- 2 Torr and brain tissue PO2 fell from 7.0 +/- 0.7 to essentially 0 Torr while CBF decreased 40 +/- 5 %. Cortical heat production decreased by 78 +/- 6 % while oxygen use declined by 90 +/- 3 %. Glucose uptake increased significantly relative to oxygen use and lactate concentration increased in sagittal sinus blood. We conclude that local measurements of heat production in the brain provide a useful index of overall metabolic rate, closely reflecting oxygen use in moderate hypoxia and indicating a significant contribution from anaerobic metabolism during severe asphyxia. (+info)
Adult carotid chemoafferent responses to hypoxia after 1, 2, and 4 wk of postnatal hyperoxia.
(44/274)
Exposing newborn rats to postnatal hyperoxia (60% O2) for 1-4 wk attenuates the ventilatory and phrenic nerve responses to acute hypoxia in adult rats. The goal of this research was to increase our understanding of the carotid chemoreceptor afferent neural input in this depressed response with different durations of postnatal hyperoxic exposure. Rats were exposed from a few days before birth to 1, 2, or 4 wk of 60% O2 and studied after 3-5 mo in normoxia. The rats were anesthetized with urethane. Whole carotid sinus nerve (CSN) responses to NaCN (40 microg/kg iv), 10 s of asphyxia and acute isocapnic hypoxia (arterial Po2 45 Torr) were determined. Mean CSN responses to stimuli after postnatal hyperoxia were reduced compared with controls. Responses in rats exposed to 1 wk of postnatal hyperoxia were less affected than those exposed to 2 and 4 wk of hyperoxia, which were equivalent to each other. These studies illustrate the importance of normoxia during the first 2 wk of life in development of carotid chemoreceptor afferent function. (+info)
Key neuroprotective role for endogenous adenosine A1 receptor activation during asphyxia in the fetal sheep.
(45/274)
BACKGROUND AND PURPOSE: The fetus is well known to be able to survive prolonged exposure to asphyxia with minimal injury compared with older animals. We and others have observed a rapid suppression of EEG intensity with the onset of asphyxia, suggesting active inhibition that may be a major neuroprotective adaptation to asphyxia. Adenosine is a key regulator of cerebral metabolism in the fetus. METHODS: We therefore tested the hypothesis that infusion of the specific adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), given before 10 minutes of profound asphyxia in near-term fetal sheep, would prevent neural inhibition and lead to increased brain damage. RESULTS: DPCPX treatment was associated with a transient rise and delayed fall in EEG activity in response to cord occlusion (n=8) in contrast with a rapid and sustained suppression of EEG activity in controls (n=8). DPCPX was also associated with an earlier and greater increase in cortical impedance, reflecting earlier onset of primary cytotoxic edema, and a significantly smaller reduction in calculated cortical heat production after the start of cord occlusion. After reperfusion, DPCPX-treated fetuses but not controls developed delayed onset of seizures, which continued for 24 hours, and sustained greater selective hippocampal, striatal, and parasagittal neuronal loss after 72-hour recovery. CONCLUSIONS: These data support the hypothesis that endogenous activation of the adenosine A1 receptor during severe asphyxia mediates the initial suppression of neural activity and is an important mechanism that protects the fetal brain. (+info)
DROWNING: ITS MECHANISM AND TREATMENT.
(46/274)
Pertinent experimental work and literature relative to drowning are reviewed. The different concepts of the mechanism of drowning are dealt with and the view is emphasized that asphyxia is complicated by hemodilution in fresh water and by hemo-concentration in salt water, with resulting electrolyte imbalance. A short description is given of the sequence of events in drowning. Lethal heart failure has occurred as early as two minutes after total submersion. Treatment consists of artificial respiration, cardiac massage, correction of the electrolyte imbalance and continued observation for complications. The danger from hyperventilation in underwater swimming, of cases of so-called "secondary" drowning and the use of diatoms as a proof of drowning are mentioned. (+info)
Buprenorphine in drug-facilitated sexual abuse: a fatal case involving a 14-year-old boy.
(47/274)
The first case involving repetitive sexual abuse linked to the use of buprenorphine is reported. Under the tradename Subutex, buprenorphine is largely used for the substitution management of opiate-dependent individuals, but it can also be easily found on the black market. A 14-year-old boy was found dead at the home of a well-known sex offender of minors. At the autopsy, no particular morphological changes were noted, except for pulmonary and visceral congestion. There was no evidence of violence, and no needle marks were found by the pathologist. Toxicological analyses, as achieved by liquid chromatography-mass spectrometry, demonstrated both recent and repetitive buprenorphine exposure in combination with nordiazepam. Buprenorphine concentrations were 1.1 ng/mL and 23 pg/mg in blood and hair, respectively. The boy's death was attributed to accidental asphyxia in a facilitated repetitive sexual abuse situation due to the combination of buprenorphine and benzodiazepines, even at therapeutic concentrations. The use of buprenorphine as a sedative drug was not challenged by the perpetrator. (+info)
Difference in end-tidal CO2 between asphyxia cardiac arrest and ventricular fibrillation/pulseless ventricular tachycardia cardiac arrest in the prehospital setting.
(48/274)
INTRODUCTION: There has been increased interest in the use of capnometry in recent years. During cardiopulmonary resuscitation (CPR), the partial pressure of end-tidal carbon dioxide (PetCO2) correlates with cardiac output and, consequently, it has a prognostic value in CPR. This study was undertaken to compare the initial PetCO2 and the PetCO2 after 1 min during CPR in asphyxial cardiac arrest versus primary cardiac arrest. METHODS: The prospective observational study included two groups of patients: cardiac arrest due to asphyxia with initial rhythm asystole or pulseless electrical activity, and cardiac arrest due to acute myocardial infarction or malignant arrhythmias with initial rhythm ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT). The PetCO2 was measured for both groups immediately after intubation and then repeatedly every minute, both for patients with and without return of spontaneous circulation (ROSC). RESULTS: We analyzed 44 patients with asphyxial cardiac arrest and 141 patients with primary cardiac arrest. The first group showed no significant difference in the initial value of the PetCO2, even when we compared those with and without ROSC. There was a significant difference in the PetCO2 after 1 min of CPR between those patients with ROSC and those without ROSC. The mean value for all patients was significantly higher in the group with asphyxial arrest. In the group with VF/VT arrest there was a significant difference in the initial PetCO2 between patients without and with ROSC. In all patients with ROSC the initial PetCO2 was higher than 10 mmHg. CONCLUSIONS: The initial PetCO2 is significantly higher in asphyxial arrest than in VT/VF cardiac arrest. Regarding asphyxial arrest there is also no difference in values of initial PetCO2 between patients with and without ROSC. On the contrary, there is a significant difference in values of the initial PetCO2 in the VF/VT cardiac arrest between patients with and without ROSC. This difference could prove to be useful as one of the methods in prehospital diagnostic procedures and attendance of cardiac arrest. For this reason we should always include other clinical and laboratory tests. (+info)