Journal of clinical monitoring最新文献_第8页

Near continuous cardiac output by thermodilution. 热稀释引起的近连续心输出量。

Journal of clinical monitoring Pub Date : 1997-07-01 DOI: 10.1023/a:1007332517810

J R Jansen, R W Johnson, J Y Yan, P D Verdouw

{"title":"Near continuous cardiac output by thermodilution.","authors":"J R Jansen, R W Johnson, J Y Yan, P D Verdouw","doi":"10.1023/a:1007332517810","DOIUrl":"https://doi.org/10.1023/a:1007332517810","url":null,"abstract":"A new thermodilution method for frequent (near continuous) estimation of cardiac output, without manual injection of fluid into the blood, was tested. The method utilizes a pulmonary artery catheter equipped with a fluid filled heat exchanger. The technique is based on cyclic cooling of the blood in the right atrium and measurement of the temperature changes in the pulmonary artery. Using this technique, a new estimate of cardiac output can be obtained every 32 s. Cardiac output estimates, obtained for a running mean of three measurements with this method, were compared to the mean of three conventional thermodilution measurements. The measurements were obtained during short periods of stable respiration and circulation. In six pigs, we made 46 paired measurements of conventional thermodilution (TD) and near continuous (TDc) thermodilution. The cardiac output (COTD) ranged from 2.4-13.7 l/min (mean 5.4 l/min). The best linear fit through the paired data points was COTDc = -0.57 + 1.01 COTD. The mean difference between the methods was -0.50 l/min (S.D. = 0.39). The mean coefficient of variation of repeated measurements with the near continuous thermodilution was 3.6%. Considering changes of more than 0.25 l/min to be significant, all changes in cardiac output measured by conventional thermodilution were followed by the running mean of three near continuous thermodilution estimates. This study demonstrates the feasibility of the new method to monitor cardiac output, and to detect all changes greater than 0.25 l/min.","PeriodicalId":77199,"journal":{"name":"Journal of clinical monitoring","volume":"13 4","pages":"233-9"},"PeriodicalIF":0.0,"publicationDate":"1997-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/a:1007332517810","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20212683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Assessment of errors when expiratory condensate PCO2 is used as a proxy for mixed expired PCO2 during mechanical ventilation. 在机械通气期间，呼气冷凝PCO2被用作混合呼气PCO2的代理时的误差评估。

Journal of clinical monitoring Pub Date : 1997-07-01 DOI: 10.1023/a:1007305902518

H Imanaka, D Hess, A al-Himyary, L M Bigatello, R Ritz, R M Kacmarek, W E Hurford

{"title":"Assessment of errors when expiratory condensate PCO2 is used as a proxy for mixed expired PCO2 during mechanical ventilation.","authors":"H Imanaka, D Hess, A al-Himyary, L M Bigatello, R Ritz, R M Kacmarek, W E Hurford","doi":"10.1023/a:1007305902518","DOIUrl":"https://doi.org/10.1023/a:1007305902518","url":null,"abstract":"Objectives: We designed a series of experiments to determine whether expiratory water condensate (PconCO2) can be used as a proxy for mixed expired gas collection.Methods: In 18 adult mechanically ventilated patients with ARDS (40 samples), simultaneous collections of arterial blood, expiratory water trap condensate, mixed expired gas, and minute ventilation were used to calculate VCO2 and VD/VT. To assess the effect of temperature, a constant gas flow (PCO2 10-30 mm Hg) was bubbled through water at temperatures of 19.5-37 degrees C. Gas and water samples were collected, immediately analyzed for PCO2, and a temperature correction factor was calculated. A lung model was constructed using a 5 L anesthesia bag connected to a mechanical ventilator with a heated humidifier. Temperature at the Y-piece was set to approximately 37 degrees C and CO2 was injected into the bag to establish an end-tidal PCO2 of 20-70 mm Hg. After equilibration, condensate was collected, PCO2 was measured, and the temperature-corrected PCO2 was compared to PECO2. The capnogram at points along the expiratory limb circuit was used to evaluate gas mixing.Results: There was an over-estimation of PECO2 by PconCO2 (p < 0.001) for the patient data, resulting in an underestimation of VD/VT (p < 0.001) and an overestimation of VCO2 (p < 0.001). The temperature correction factor for PCO2 in water was -0.010 (about half of the factor used for whole blood). The bias between temperature-corrected PconCO2 and PECO2 was 0.3 +/- 3.2 mm Hg in the lung model. Mixing in the expiratory limb was poor, as evaluated by the capnogram.Conclusions: Even with temperature correction, we failed to precisely predict PECO2 from PconCO2. For measurement of VD/VT and VCO2, we do not recommend methods that use PconCO2.","PeriodicalId":77199,"journal":{"name":"Journal of clinical monitoring","volume":"13 4","pages":"215-22"},"PeriodicalIF":0.0,"publicationDate":"1997-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/a:1007305902518","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20212680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An integrated graphic data display improves detection and identification of critical events during anesthesia. 集成的图形数据显示提高了麻醉过程中关键事件的检测和识别。

Journal of clinical monitoring Pub Date : 1997-07-01 DOI: 10.1023/a:1007395901610

P Michels, D Gravenstein, D R Westenskow

{"title":"An integrated graphic data display improves detection and identification of critical events during anesthesia.","authors":"P Michels, D Gravenstein, D R Westenskow","doi":"10.1023/a:1007395901610","DOIUrl":"10.1023/a:1007395901610","url":null,"abstract":"Objective: To show that an integrated graphic data display can shorten the time taken to detect and correctly identify critical events during anesthesia.Methods: We developed a graphic display which presents 30 anesthesia-related physiologic variables as shapes and colors, rather than traditional digits and waveforms. To evaluate the new display, we produced four critical events on a computer-based anesthesia simulator and asked two groups of five anesthesiologists to identify the events as quickly as possible. One group observed the new display while the other group viewed a traditional cardiovascular monitor with digital and waveform displays.Results: The group which observed the integrated graphic display saw changes caused by inadequate paralysis 2.4 min sooner, and changes caused by a cuff leak 3.1 min sooner than those observing the traditional display. The integrated display group correctly identified the reason for the change 2.8 min sooner for inadequate paralysis, 3.1 min sooner for cuff leak and 3.1 min sooner for bleeding. These differences were all statistically significant.Conclusions: The results show that some simulated critical events are detected and correctly identified sooner, when an anesthesiologist views an integrated graphic display, rather than a traditional digital/waveform monitor.","PeriodicalId":77199,"journal":{"name":"Journal of clinical monitoring","volume":"13 4","pages":"249-59"},"PeriodicalIF":0.0,"publicationDate":"1997-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20212685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Template for rapid analysis of the Sonoclot Signature. 模板快速分析Sonoclot签名。

Journal of clinical monitoring Pub Date : 1997-07-01 DOI: 10.1023/a:1007358518992

M A Lyew, W C Spaulding

引用次数: 4

pH change in tissue can be detected using infra-red light reflectance spectroscopy. 利用红外光反射光谱法可以检测到组织中的pH值变化。

Journal of clinical monitoring Pub Date : 1997-07-01

J W Severinghaus

引用次数: 0

Audio signal feedback light source-guided endotracheal intubation. 音频信号反馈光源引导气管插管。

Journal of clinical monitoring Pub Date : 1997-07-01 DOI: 10.1023/a:1007308918197

S Yang

{"title":"Audio signal feedback light source-guided endotracheal intubation.","authors":"S Yang","doi":"10.1023/a:1007308918197","DOIUrl":"https://doi.org/10.1023/a:1007308918197","url":null,"abstract":"Objective: Light source-guided endotracheal intubation, whether by lighted stylet or fiber-optic laryngoscopy may potentially be improved by electrical conversion of the detected optical signal to an audio signal. The audio signal thus serves as a feedback guiding signal.Methods: The optical-to-audio signal conversion is accomplished using a light source, an optical detector and a voltage-to-frequency conversion system. The intensity of the detected optical signal determines the frequency of the audio-signal. Therefore the frequency of the audio signal varies as the light source approaches the optical detector. The light source may be placed in the orotracheal airway and the detector may be placed on cricothyroid membrane or these components may be placed in the opposite orientation.Results: The theory of operation and the construction of a prototype are described.Conclusion: This optical-audio signal feedback system may be used to direct the lighted stylet from the oral cavity into the laryngeal-tracheal pathway. This may potentially be a more sensitive technique than the currently used visual intensity detection.","PeriodicalId":77199,"journal":{"name":"Journal of clinical monitoring","volume":"13 4","pages":"229-32"},"PeriodicalIF":0.0,"publicationDate":"1997-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/a:1007308918197","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20212682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Clinical evaluation of an automatic blood pressure controller during cardiac surgery. 心脏手术中自动血压控制器的临床评价。

Journal of clinical monitoring Pub Date : 1997-07-01 DOI: 10.1023/a:1007389631055

R H Meijers, D Schmartz, F R Cantraine, L Barvais, A A d'Hollander, J A Blom

{"title":"Clinical evaluation of an automatic blood pressure controller during cardiac surgery.","authors":"R H Meijers, D Schmartz, F R Cantraine, L Barvais, A A d'Hollander, J A Blom","doi":"10.1023/a:1007389631055","DOIUrl":"https://doi.org/10.1023/a:1007389631055","url":null,"abstract":"Objective: During surgery, computers can be of great use to support the anesthesiologist in providing task automation. In this paper we describe a closed loop blood pressure controller and show the results of its clinical evaluation.Methods: The controller is based on a simple and robust Proportional-Integral controller and a supervising, rule based, expert system. Adaptive control is necessary because the sensitivity of the patients to sodium nitroprusside varies over a wide range. Thirty-three clinical tests during cardiac surgery, including the cardiopulmonary bypass phase, were performed.Results: On average the controller was in automatic mode for 90.6 +/- 9.6% of the time. The performance during automatic control showed the mean arterial pressure to be within 10 mmHg of the setpoint for 71.4 +/- 15.5% of the time. The average absolute distance to the setpoint was 8.1 +/- 7.2 mmHg.Conclusions: The overall performance of the controller was noted as very satisfactory by the anesthesiologists.","PeriodicalId":77199,"journal":{"name":"Journal of clinical monitoring","volume":"13 4","pages":"261-8"},"PeriodicalIF":0.0,"publicationDate":"1997-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/a:1007389631055","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20212686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Nitric oxide (NO) measurement accuracy. 一氧化氮（NO）测量精度。

Journal of clinical monitoring Pub Date : 1997-07-01 DOI: 10.1023/a:1007300814136

M Nishimura, H Imanaka, A Uchiyama, C Tashiro, D Hess, R M Kacmarek

{"title":"Nitric oxide (NO) measurement accuracy.","authors":"M Nishimura, H Imanaka, A Uchiyama, C Tashiro, D Hess, R M Kacmarek","doi":"10.1023/a:1007300814136","DOIUrl":"10.1023/a:1007300814136","url":null,"abstract":"Background: Evaluation of the clinical utility of NO requires accurate assessment of inspired [NO]. Currently, chemiluminescence analyzers are the clinical standard for analysis; however, their performance in the clinical setting has not been systemically evaluated.Methods: We evaluated the performance of four chemiluminescence analyzers (270B NOA, Sievers Instruments, Inc.; CLA 510S, Horiba Co., Ltd.; CLD 700 AL, Eco Physics Corp.; Model 42, Thermo Environmental Instruments Inc.) in simulated clinical settings. Transport delay and dynamic 95% response time were measured by the balloon in a glass chamber puncture technique. Fluctuating [NO] in a continuous flow of gas and [NO] during mechanical ventilation, where NO was premixed prior to entering the ventilator, were evaluated.Results: Transport delay ranged from 1.02 +/- 0.02 to 24.36 +/- 2.47 s (p < 0.05) and the 95% response time ranged from 0.22 +/- 0.04 to 70.03 +/- 0.03 s (p < 0.05). Accurate analysis of [NO] in a continuous flow system was only possible with the most rapid response analyzer (270B NOA). All other analyzers under reported the maximum [NO] (p < 0.05) and over reported the minimum [NO] (p < 0.05). All analyzers accurately determined [NO] in the inspiratory limb of the ventilator circuit, but none accurately determined [NO] at the airway opening.Conclusions: Measurements of inhaled [NO] can vary greatly, dependent upon the performance characteristics of the analyzer and the location of NO analysis. All studies evaluating the clinical use of NO should fully describe the technical gas delivery methodology and the response time and transport delay of the chemiluminescence analyzer used.","PeriodicalId":77199,"journal":{"name":"Journal of clinical monitoring","volume":"13 4","pages":"241-8"},"PeriodicalIF":0.0,"publicationDate":"1997-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20212684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cardiogenic oscillations may be masked by the breathing system configuration. 心源性振荡可能被呼吸系统结构所掩盖。

Journal of clinical monitoring Pub Date : 1997-07-01 DOI: 10.1023/a:1007357931536

R P Haridas, W B Murray, N R Bhimsan

引用次数: 1

Arterial-pulse oximetry loops: a new method of monitoring vascular tone. 动脉-脉搏血氧循环:一种监测血管张力的新方法。

Journal of clinical monitoring Pub Date : 1997-07-01 DOI: 10.1023/a:1007361020825

K H Shelley, W B Murray, D Chang

{"title":"Arterial-pulse oximetry loops: a new method of monitoring vascular tone.","authors":"K H Shelley, W B Murray, D Chang","doi":"10.1023/a:1007361020825","DOIUrl":"https://doi.org/10.1023/a:1007361020825","url":null,"abstract":"Objective: We report the off-line calculation of the vascular compliance of the finger and suggest the continuous on-line use of this methodology as an aid to monitoring the peripheral vascular resistance. This method consists of the simultaneous analysis of the waveform signals from the pulse oximeter monitors and the arterial pressure as indicators of \"volume\" and pressure respectively to continuously calculate the vascular \"compliance\" (volume change per unit pressure change). This should be seen as a \"relative compliance\" as the pulse plethysmograph signal is not calibrated. This new methodology allows for continuous monitoring of peripheral vascular compliance as a beat-to-beat indicator of peripheral vascular resistance. The vaso-constrictors, phenylephrine and ephedrine, were shown to decrease the compliance as predicted.Methods: The arterial pressure and pulse oximeter waveforms were obtained during routine anesthetic care. The waveforms were collected with a computer data-acquisition system and then analyzed \"off-line\" as an indirect indicator of total vascular tone. Demographic and clinical information including drug administration were recorded.Results: A case report is presented using this new form of analysis. Vascular compliance changes induced by phenylephrine and ephedrine were studied. A dose response curve of peripheral vascular compliance to phenylephrine was generated from these data.Conclusions: By plotting the pulse oximeter waveforms versus the arterial waveforms, multiple volume versus pressure (relative compliance) loops were obtained. Analysis of these loops may assist in the monitoring of vascular compliance.","PeriodicalId":77199,"journal":{"name":"Journal of clinical monitoring","volume":"13 4","pages":"223-8"},"PeriodicalIF":0.0,"publicationDate":"1997-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/a:1007361020825","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20212681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 55