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Biomedical subjects

R S Simon

Publications and source records attributed to R S Simon.

34 records · Page 2Linked to original sources
PubMed1976

[The effect of different ventilation under anaesthesia upon intracerebral x-ray findings (author's transl)].

In 35 patients carotid angiography was performed under general anaesthesia (Halothane or NLA) under hyper- and hypoventilation conditions. Hyperventilation led to arterial vasoconstriction. The changes in vessel diameter correlated with the difference from hyper- to hypoventilation. Under hypoventilation the veins were filled earlier and better. In case of tumour and in case of insult with angiographically verified blush the pathological vessels were better stained with hyperventilation. Anaesthetics did not influence the X-Ray findings. Patients should be hyperventilated during carotid angiography. Only in certain cases an angiogram under hypoventilation allows a clearer X-Ray interpretation.

Adult↗
PubMed1975

Optimal use of nitrogen to suppress the high pressure nervous syndrome.

Five subjects were compressed to 1000 ft (31 ATA) for 2 h breathing 3.2 ATA nitrogen, 0.5 ATA oxygen, and the remainder helium. The compression took 33 min with a 10-s stage at 50 ft (2.5 ATA), 1 MIN AT 320 FT (10.7 ATA), and 2 min at 700 ft (22 ATA). Hypothetically, this 1:10 ratio for nitrogen-helium partial pressures should induce neither nitrogen narcosis nor the High Pressure Nervous Syndrome (HPNS). Tests, therefore, were made during the experiment of postural tremor, spontaneous electroencephalogram, psychomotor and intellectual activities, and subjective sensations. One diver worked underwater for 40 min on a simulated engineering assembly while breathing with a closed-circuit breathing apparatus and wearing a battery-heated suit in water at 56 degrees F. Decompression was in 4 d using 0.8 ATA oxygen and helium. The performance tests indicated no narcosis and little or no signs of HPNS. No tremor or EEG changes were seen. The "wet" diver reported sensations of mild euphoria but the other four reported no difficulties. No nausea or dizziness of HPNS was reported. It is concluded that use of a ratio of 1:10::N2:He is effective in the control of narcosis and HPNS during rapid compression to 1000 ft (31 ATA).

Atmospheric Pressure↗