scholarly journals Electronic Digital Computer Control of Ventilation and Anaesthesia

1973 ◽  
Vol 1 (5) ◽  
pp. 382-392 ◽  
Author(s):  
D. G. Lampard ◽  
J. R. Coles ◽  
W. A. Brown
Keyword(s):  
Digital Computer ◽  
Computer Control ◽  
Computer Control System ◽  
Controlled System ◽  
Physiological Variables ◽  
Arterial Blood ◽  
Random Disturbances ◽  
Integrated Electromyogram ◽  
Time Courses ◽  
End Tidal

The use of a small digital computer to control a number of interactive physiological variables is demonstrated. It is shown that by monitoring the values of end tidal per cent CO2, inspired O2 percentage and mean arterial blood pressure, a computer-controlled system can regulate the ventilation and anaesthesia of an animal within fine tolerances. Similarly it is shown that by controlling the infusion of muscle relaxant, the integrated electromyogram of a muscle can be maintained at any desired level. The computer control system automatically allows for random disturbances in system parameters in maintaining set levels of the controlled variables. The system responds rapidly to changes in the desired level of variables, and prescribed time courses of variables can be followed.

scholarly journals Computer Controlled System for the Magnetron Sputtering Deposition of the Metallic Multilayers

2014 ◽  
Vol 60 (4) ◽  
pp. 291-298 ◽  
Author(s):  
Konstanty Marszałek ◽  
Jacek Stępień ◽  
Ryszard Mania
Keyword(s):  
Magnetron Sputtering ◽  
Computer Control ◽  
Rotation Velocity ◽  
Metallic Multilayers ◽  
Computer Control System ◽  
Controlled System ◽  
Sputtering Deposition ◽  
High Temperature Synthesis ◽  
Intermetallic Compound Formation ◽  
Good Repeatability

Abstract Deposition of the metallic multilayers is a part of the scientific program on the chemical reaction leading to intermetallic compound formation. This reaction is known as self propagation high temperature synthesis (SHS). The key problem in this investigation is to produce the metallic multilayer system with good repeatability of thin films thicknesses. Thin should be thin, parallel and with low volume of intermixing region between components. Computer control system for the pulsed (mid frequency MF) magnetron sputtering equipment dedicated for metallic multilayers deposition is presented in this paper. The rotation velocity of the sample holder and the gas inlet through membrane valves are the main parameters controlled by the system. Parameters of the magnetron gun power supply, sample temperature and technological gas pressure are registered. The process cards which define all process parameters are collected for each dedicated process type. All cards are collected in a process cards library which permits for full automatization of all operations. Software was written in a graphical LabVIEW environment.

The effect of nimodipine on cerebral oxygenation in patients with poor-grade subarachnoid hemorrhage

2004 ◽  
Vol 101 (4) ◽  
pp. 594-599 ◽  
Author(s):  
Michael F. Stiefel ◽  
Gregory G. Heuer ◽  
John M. Abrahams ◽  
Stephanie Bloom ◽  
Michelle J. Smith ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Subarachnoid Hemorrhage ◽  
Brain Tissue ◽  
Cerebral Oxygenation ◽  
Content Type ◽  
Poor Grade ◽  
Physiological Variables ◽  
Arterial Blood ◽  
End Tidal ◽  
Fine Print

Object. Nimodipine has been shown to improve neurological outcome after subarachnoid hemorrhage (SAH); the mechanism of this improvement, however, is uncertain. In addition, adverse systemic effects such as hypotension have been described. The authors investigated the effect of nimodipine on brain tissue PO2. Methods. Patients in whom Hunt and Hess Grade IV or V SAH had occurred who underwent aneurysm occlusion and had stable blood pressure were prospectively evaluated using continuous brain tissue PO2 monitoring. Nimodipine (60 mg) was delivered through a nasogastric or Dobhoff tube every 4 hours. Data were obtained from 11 patients and measurements of brain tissue PO2, intracranial pressure (ICP), mean arterial blood pressure (MABP), and cerebral perfusion pressure (CPP) were recorded every 15 minutes. Nimodipine resulted in a significant reduction in brain tissue PO2 in seven (64%) of 11 patients. The baseline PO2 before nimodipine administration was 38.4 ± 10.9 mm Hg. The baseline MABP and CPP were 90 ± 20 and 84 ± 19 mm Hg, respectively. The greatest reduction in brain tissue PO2 occurred 15 minutes after administration, when the mean pressure was 26.9 ± 7.7 mm Hg (p < 0.05). The PO2 remained suppressed at 30 minutes (27.5 ± 7.7 mm Hg [p < 0.05]) and at 60 minutes (29.7 ± 11.1 mm Hg [p < 0.05]) after nimodipine administration but returned to baseline levels 2 hours later. In the seven patients in whom brain tissue PO2 decreased, other physiological variables such as arterial saturation, end-tidal CO2, heart rate, MABP, ICP, and CPP did not demonstrate any association with the nimodipine-induced reduction in PO2. In four patients PO2 remained stable and none of these patients had a significant increase in brain tissue PO2. Conclusions. Although nimodipine use is associated with improved outcome following SAH, in some patients it can temporarily reduce brain tissue PO2.

A computer-control program for TEM in situ fatigue experiments

1989 ◽  
Vol 47 ◽  
pp. 620-621
Author(s):  
Kenneth S. Vecchio ◽  
John A. Hunt
Keyword(s):  
Slow Crack Growth ◽  
Computer Control ◽  
Control Program ◽  
Video Tape ◽  
Computer Control System ◽  
Transmission Electron ◽  
In Situ Experiments ◽  
Tremendous Amount ◽  
And Control

In-situ experiments conducted within a transmission electron microscope provide the operator a unique opportunity to directly observe microstructural phenomena, such as phase transformations and dislocation-precipitate interactions, “as they happen”. However, in-situ experiments usually require a tremendous amount of experimental preparation beforehand, as well as, during the actual experiment. In most cases the researcher must operate and control several pieces of equipment simultaneously. For example, in in-situ deformation experiments, the researcher may have to not only operate the TEM, but also control the straining holder and possibly some recording system such as a video tape machine. When it comes to in-situ fatigue deformation, the experiments became even more complicated with having to control numerous loading cycles while following the slow crack growth. In this paper we will describe a new method for conducting in-situ fatigue experiments using a camputer-controlled tensile straining holder.The tensile straining holder used with computer-control system was manufactured by Philips for the Philips 300 series microscopes. It was necessary to modify the specimen stage area of this holder to work in the Philips 400 series microscopes because the distance between the optic axis and holder airlock is different than in the Philips 300 series microscopes. However, the program and interfacing can easily be modified to work with any goniometer type straining holder which uses a penrmanent magnet motor.

scholarly journals PEP Computer Control System

1979 ◽  
Vol 26 (3) ◽  
pp. 3267-3271 ◽  
Author(s):  
A. W. Chao ◽  
R. A. Early ◽  
J. D. Fox ◽  
A. E. Gromme ◽  
R. H. Helm ◽  
...  
Keyword(s):  
Control System ◽  
Computer Control ◽  
Computer Control System

scholarly journals 217 The end-tidal and arterial carbon dioxide gradient in serious traumatic brain injury after pre-hospital emergency anaesthesia: a retrospective observational study

2020 ◽  
Vol 37 (12) ◽  
pp. 847.1-847
Author(s):  
James Price ◽  
Daniel Sandbach ◽  
Ari Ercole ◽  
Alastair Wilson ◽  
Ed Barnard
Keyword(s):  
Carbon Dioxide ◽  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Thoracic Injury ◽  
Secondary Brain Injury ◽  
Hospital Emergency ◽  
Hospital Arrival ◽  
Arterial Blood ◽  
End Tidal ◽  
Emergency Anaesthesia

Aims/Objectives/BackgroundIn the United Kingdom (UK), 20% of patients with severe traumatic brain injury (TBI) receive pre-hospital emergency anaesthesia (PHEA). Current guidance recommends an end-tidal carbon dioxide (ETCO2) of 4.0–4.5kPa to achieve a low-normal arterial partial pressure of CO2 (PaCO2), and reduce secondary brain injury. This recommendation assumes a 0.5kPa ETCO2-PaCO2 gradient. However, the gradient in the acute phase of TBI is unknown. Our primary aim was to report the ETCO2-PaCO2 gradient of TBI patients at hospital arrival.Methods/DesignA retrospective cohort study of adult patients with serious TBI, who received a PHEA by a pre-hospital critical care team in the East of England between 1st April 2015 to 31st December 2017. Linear regression was performed to test for correlation and reported as R-squared (R2). A Bland-Altman plot was used to test for paired ETCO2 and PaCO2 agreement and reported with 95% confidence intervals (95%CI). ETCO2-PaCO2 gradient data were compared with a two-tailed, unpaired, t-test.Results/Conclusions107 patients were eligible for inclusion. Sixty-seven patients did not receive a PaCO2 sample within 30 minutes of hospital arrival and were therefore excluded. Forty patients had complete data and were included in the final analysis; per protocol.The mean ETCO2-PaCO2 gradient was 1.7 (±1.0) kPa, with only moderate correlation of ETCO2 and PaCO2 at hospital arrival (R2=0.23, p=0.002). The Bland-Altman bias was 1.7 (95%CI 1.4–2.0) kPa with upper and lower limits of agreement of 3.6 (95%CI 3.0–4.1) kPa and -0.2 (95%CI -0.8–0.3) kPa respectively. There was no significant gradient correlation in patients with a co-existing serious thoracic injury (R2=0.13, p=0.10), and this cohort had a larger ETCO2-PaCO2 gradient, 2.0 (±1.1) kPa, p=0.01. Patients who underwent pre-hospital arterial blood sampling had an arrival PaCO2 of 4.7 (±0.2) kPa.Lower ETCO2 targets than previously recommended may be safe and appropriate. The use of pre-hospital PaCO2 measurement is advocated.

Sign in / Sign up

Export Citation Format

Share Document