Case 1
The decedent was 65 years old. Her career as a registered nurse ended at age 55 when she experienced the first of several strokes that contributed to decline in health, memory, and sensory perceptions. She characterized these as "small strokes but with very big consequences." At age 62 she had a heart attack. The decedent was single, childless, and lived independently. She could not tolerate the possibility of more strokes and institutional care.
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Considering the time of the first breath inside the helium environment as 0 seconds, the observations are as follows: loss of consciousness at 10 seconds (about 3 breaths); breathing then accelerated for about 40 seconds. At 1:00 the heart rate had accelerated to 114 and SPO2 dropped to 39%. At about 2:00 breathing had stopped, the oximeter could not fix on a heart rate and SPO2 was 37%. At 3:00 the oximeter was still not measuring any heart rate and SPO2 was 34%, which is the minimum range for the device. At 3:45 the jaw fell slack and the tongue extended. Although breathing had ceased after 2 minutes there were 4 terminal gasps at 4:00, 4:45, 6:40, and 8:36. At no point in the dying process was there any extension or contraction reflex of the arms or legs.
Case 2
The decedent was 70 years old and since 1979 had suffered with myalgic encephalomyelitis (ME). Health decline was such that nearly all of her physical activity was oriented to basic survival needs. The decedent was divorced, childless, and lived independently, but with weekly home support service. She participated in Internet support groups for ME, primarily to lend support to younger sufferers of the illness. The decedent believed that most ME patients could make adaptations to enjoy some quality of life, but that after more than 25 years with the disease she believed that her better health was irretrievably lost.
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Considering the time of the first breath inside the helium environment as 0 seconds, the following was observed: loss of consciousness at about 12 seconds followed by accelerated respiration continuing to about 55 seconds; at around 40 seconds there were reflexes in the right arm and in both legs. The reflex in the right arm was a single, slow contraction at the elbow. The extension reflex in the legs lasted approximately 15 to 20 seconds.
At 1:44 there was a loud gurgling expiratory breath, possibly due to carbon dioxide escaping (from the 2 glasses of sparkling wine consumed earlier). At this time muscle tone relaxed and the head fell slightly to the right into a final resting position (Fig. 6). Very faint gasps occurred at 3:32, 4:26, and 4:55; the tongue distended at 4:55; further faint gasps occurred at 5:15, 5:47, 6:11, 6:36, and 6:46; barely perceptible muscular twitching of the right cheek took place from about 6:50 to 7:05; at 7:25 a hardly audible snort of the sinus replaced the faint oral gasping; further faint sinus snorts occurred at 7:46, 8:29, 8:51, 9:46, and 11:11, after which all visible respiratory movement stopped.
Source:
https://www.tesble.com/10.1097/PAF.0b013e3181d749d7