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Arterial tonometry is a technique used to measure arterial blood pressure noninvasively. The authors developed a new tonometer system containing an array of 15 piezoresistive pressure transducers, a mechanical positioning system, signal conditioning and multiplexing electronics, and a display and control console. The authors evaluated the accuracy, reliability, and clinical acceptability of this system by comparing tonometric blood pressure measurements with intraarterial blood pressure measurements in 60 anesthetized patients. Blood pressure was measured intraarterially in either the right or left radial artery by a Gould P23XL calibrated transducer, whereas blood pressure was measured by tonometer at the radial artery of the other arm. The tonometric waveform was similar to the intraarterial waveform. Simultaneous tonometer and intraarterial systolic blood pressures of the 60 patients (3,036 data sets) had an overall regression coefficient, r = 0.97, and an equation, regression equation = 0.95X + 5.8. Similar values were obtained for mean and diastolic pressures. Regression analyses of the paired tonometric and intraarterial blood pressure values showed good correlations in both sexes and in ages ranging from 8 to 82 yr (r = 0.94-0.97). Mean absolute values of error (precision) for the systolic, mean, and diastolic measurements did not differ significantly among the five systolic, five mean, and four diastolic pressure groups and ranged from 3.6 to 6.6 mmHg, with negligible bias, with intraarterial pressure used as the reference. Bias for the various pressure groups was small: -0.9-3.6 mmHg for systolic; -3.0-0.7 mmHg for mean; and -2.1-4.5 mmHg for diastolic. The "limits of agreement" (mean difference +/- two standard deviations) were within an acceptable range for clinical anesthesia.(ABSTRACT TRUNCATED AT 250 WORDS)

The authors evaluated the effi ciency and reproducibility of cardiac output measurement by esophageal continuous-wave Doppler ultra sonography (ECO). A total of 114 si multaneous measurements of ECO and thermodilution cardiac output (TDCO) were compared in 25 surgi cal patients undergoing general anes thesia in the supine position. ECO could be obtained easily with mini mal experience by means of a com mercially available Doppler cardiac output monitor. There was a signifi cant correlation between ECO and TDCO (

先天性第V因子欠乏症を合併する小児の口蓋裂形成術の麻酔管理を経験した.手術に先立ち正常血漿添加試験を行い,活性部分トロンボプラスチン時間(APTT)が第V因子活性の指標として有用であること,血漿添加によりAPTTが短縮されることを確認した.術中の第V因子補充療法として新鮮凍結血漿(FFP)投与を行い,初回補充として20ml/kg投与した.小児患者では循環系に対する容量負荷が懸念されることからFFP投与と同時に脱血を行った.初回投与後にAPTT値が40秒と改善したのを確認後,手術を開始した.術後2日間に10ml/kgのFFP追加投与を2回行いAPTT値を50秒以下に維持し,全経過を通じ異常な出血をみることもなく良好な経過を得た.

A newly developed arterial tonometer enabled us to measure the blood pressure waveforms in addition to determining systolic and diastolic pressures noninvasively and continuously. Twenty-eight adult patients undergoing orthopedic surgery under controlled hypotension were studied. Systolic blood pressure was reduced to two-thirds of baseline values with an infusion of nitroglycerin during nitrous oxide/enflurane anesthesia. Intraarterial blood pressures were simultaneously measured in either the right or the left radial artery with a cannula and a Gould P23XL calibrated transducer; tonometric monitoring was performed on the contralateral radial artery using a Colin CBM-3000 instrument. The outputs of the two blood pressure measurement instruments were recorded for later data analysis. The shape of the tonometric pressure waveform was nearly identical to the waveform recorded intraarterially even during controlled hypotension. Regression analyses of 2039 paired tonometric and intraarterial blood pressure values during the hypotensive period showed good correlations (r = 0.78 for systolic, r = 0.81 for mean, and r = 0.70 for diastolic pressures). The accuracy of systolic, mean, and diastolic readings was from 4 to 7 mm Hg with negligible bias and did not differ significantly among six systolic, four mean, and four diastolic pressure groups. Our results indicate that arterial tonometry can provide accurate, reliable, and real-time monitoring of blood pressure even during controlled hypotension.

Clinical evaluation of continuous\(S\bar v_{O_2 } \) monitoring during general anesthesia was made in 21 surgical patients utilizing a fiberoptic reflectometry system combined with a pulmonary artery flow-directed balloon catheter. On-line in vivo values for\(S\bar v_{O_2 } \) by the system were closely related to those obtained in vitro from a Radiometer ABL-300. There was a good correlation between changes of in vivo\(S\bar v_{O_2 } \) and corresponding changes in cardiac index. We also observed that there were significant correlations between\(S\bar v_{O_2 } \) and oxygen extraction ratio, and\(S\bar v_{O_2 } \) and oxygen delivery. These data indicate that continuous monitoring of\(S\bar v_{O_2 } \) during general anesthesia can provide on-line information not only about hemodynamic state but also on oxygen transport, which will be especially helpful in managing hemodynamicaly unstable patients during anesthesia.

We evaluate the accuracy of cardiac output measurement with esophageal Doppler ultrasonography (ECO). A total of 71 simultaneous measurement of esophageal Doppler and thermodilution cardiac output were compared in 16 patients undergoing general anesthesia in the supine position. ECO was determined easily with minimal experience, and significantly correlated with thermodilution cardiac output (TDCO) measurement ( P0.001). The regression equation obtained was Y = 0.983X + 0.019, and the correlation coefficient was 0.935. Furthermore, ECO was more reproducible than TDCO. However, ECO is not able to assess CO accurately in either lateral or prone position and after cardiopulmonary bypass in open heart surgery. Our results suggest that the esophageal Doppler technique allows a noninvasive and continuous cardiac output monitoring in patients during general anesthesia, and that it is more useful in patients for whom invasive monitoring is considered inappropriate. However, further improvement in this technique will be necessary for its routine use in clinical anesthesia.

The direct inotropic action of seven local anesthetics: procaine, mapivacaine, lidocaine, tetracaine, chloroprocaine, bupivacaine and etidocaine were compared in isolated cat papillary muscles. All of the local anesthetics produced a doserelated depression of maximal velocity of shortening (Vmax), maximal developed force (Fm) and maximal dF /dt. The more potent local anesthetics such as bupivacaine and etidocaine depressed myocardial contractility at significantly lower concentrations than the less potent local anesthetics such as lidocaine and mepivacaine. Depression of Vmax by bupivacaine or etidocaine was three times greater than that by lidocaine and ten times greater than that by procaine. At the same concentration (10−4M), direct myocardial depression was demonstrated in the following order of severity: etidocaine ≥ bupivacaine > tetracaine > chloroprocaine ≥ lidocaine > mepivacaine > procaine.