摘要:

Each time a change can be observed in the height of a manometer applied to an artery, the experimenter must ask himself which of the two factors of the arterial pressure has varied, or whether the two factors, flow (power) and resistance have been modified at the same time. In the absence of a criterion which would allow one to decide with complete certainty this litigious question, often enough physiologists have chosen the hypothesis which best accorded with their own preconceived ideas. (Author's translation.) Etienne Jules Marey, 1881

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

Changes in systolic (SP), diastolic (DP), and pulse pressures (PP) caused by various stress-induced changes (hypoxia, anemia, hypercarbia, halothane, cyclopropane) in heart rate (HR), stroke volume (SV), and total peripheral resistance (TPR) were studied in dogs and man. Pooled data from 13 separate studies (n = 85) revealed highly significant correlations of ΔSP with ΔDP (r = 0.88), and ΔSP with ΔSV (r = 0.82) only. There was no correlation of ΔSP or ΔDP with either ΔTPR or ΔHR. ΔDP correlated poorly with ΔSV, and ΔPP correlated poorly with all variables. Changes in TPR and SV could not be inferred from ΔDP or ΔPP, respectively. Within each individual group, few correlations were found except for ΔSP with ΔDP. Inferences made from diastolic or pulse-pressure measurements on the state of the circulation, particularly TPR and SV, are misleading and do not add to knowledge obtained from measurement of systolic pressure alone.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

Etidocaine, a new local anesthetic, was evaluated in a double-blind study using ulnar-nerve block. In addition, electromyography for the assessment of peripheral nerve motor blockade was investigated. Ten volunteers received bilateral ulnar-nerve blocks, in three series, to compare: 0.25 per cent etidocaine with 1 per cent lidocaine, each containing epinephrine 1:200,000; 0.5 per cent etidocaine with 1 percent lidocaine, each containing epinephrine 1:200,000; 0.5 per cent etidocaine with 1 percent lidocaine, both without epinephrine. The two anesthetics had similar rapid onsets of action. Etidocaine, 0.25 per cent, appeared equivalent to lidocaine 1 per cent and had approximately the same duration of action. Etidocaine, 0.5 per cent, twice the equivalent concentration, and lidocaine, 1 per cent, both with epinephrine, produced analgesia lasting 583 and 262 min, and motor block lasting 653 and 294 min, respectively. The same solutions without epinephrine provided analgesia for 320 and 165 min, and motor block for 353 and 139 min, respectively. Electromyography allowed determination of all phases of motor blockade.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

To test the hypothesis that anesthetic uptake varies with body size, the alveolar rates of uptake of subanesthetic concentrations of methane, cyclopropane, halothane, fluroxene, and ethyl ether were measured in rats, man, and one gray whale calf (weight 6,330 kg). Uptake was most rapid in rats, intermediate in man, and least rapid in the whale. Metabolic rate was unexpectedly high in the whale, leading to more rapid than anticipated alveolar uptake of anesthetics, which might have been still more rapid but for the effects of reduced ventilation and increased blood/gas partition coefficients. Nevertheless, the differences between the ratios of alveolar to inspired anesthetic concentrations (FA/FI) in the large and small animals were appreciable, particularly for soluble anesthetics: at 60 minutes FA/FI for halothane was 1.7 times greater in rats than in the whale, and FA/FI for ethyl ether was 2.7 times greater. The authors conclude that the rate of anesthetic uptake varies inversely with body size.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

The effect of 75 per cent nitrous oxide–oxygen upon the spontaneous unit activity of cells in Rexed laminae IV, V, and VI of the dorsal horn of spinal cats was analyzed quantitatively with the aid of several digital computer programs. Overall statistical parameters, interval histograms, and burst-interval histograms were derived. Each cell lamina was characterized by a “statistical signature.” The spontaneous activity of lamina IV cells remained unaffected by the gas. The spontaneous activity of lamina V cells showed an increase in mean interval, accounted for by an increase in interburst interval, with relative maintenance of intraburst interval duration. The spontaneous activity of lamina VI cells was increased in rate and regularized in pattern. The cellular effects of analgesic agents cannot be described by overall statistical parameters alone, but require specification of the interval “fine structure” of spontaneous unit activity.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

Survival times and hemodynamic, metabolic, and sympathoadrenal responses to progressive hemorrhagic hypotension were determined in dogs subjected to blood removal of 10 ml/kg/30 min during MAC anesthesia with cyclopropane, isoflurane, and halothane. Mean survival times ranged from 146 minutes (cyclopropane plus succinylcholine) to 247 minutes (halothane). Initially, hemodynamic function was better maintained with cyclopropane, with or without succinylcholine, and arterial epinephrine and lactate concentrations increased earlier than with isoflurane or halothane. However, with further unreplaced blood loss, hemodynamic function, O2uptake, and acid–base balance were sustained better with either isoflurane or halothane than with cyclopropane. Further studies showed that increased lactate concentration resulted from increased epinephrine concentration. During hemorrhage the initial maintenance of arterial pressure by agents such as cyclopropane, which enhances sympathoadrenal response to hemorrhagic hypotension, is achieved by mechanisms lessening the ability to survive additional blood loss. These augmented responses are, overall, undesirable additives to the anesthetic circumstance.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID