摘要:

Oxygen uptake and carbon dioxide excretion during aorto‐coronary bypass surgery were studied in seven patients by indirect calorimetry and compared to blood‐gas based measurements. Medium‐high dose fentanyl, droperidol and midazolam were used for maintaining anaesthesia. During the period of extracorporeal circulation no external oxygenator was used. Circulation was maintained by two pumps by‐passing the left and right heart respectively and the patient's lungs were ventilated with O2/N2using a Servo 900C ventilator. For indirect calorimetric measurements gas concentrations were analysed by Beckman instruments and gas volumes were measured by the Servo 900C ventilator. Oxygen uptake and carbon dioxide excretion decreased by 31% and 39%, respectively. For invasive measurements during extracorporeal circulation, arterial and venous blood gases and pump flow were used. Using pump flow instead of cardiac output when calculating oxygen uptake circumvented errors in thermodilution measurements. There was a good correlation (r = 0.88) between the invasive and the indirect calorimetric measurements. Further, there was a good correlation between naso‐pharyngeal temperature and indirect calorimetric measurements of oxygen uptake (

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03270.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The azeotropic mixture of halothane and diethyl ether (HE) may be a valuable alternative to other anaesthetic agents under circumstances such as war, civil disaster, and primitive conditions. In the present study the minimum alveolar concentrations (MACs) for HE in man (n = 25) and in pigs (n = 6) were determined. For comparison with results of other studies, the MAC for halothane in man (n = 14) was also determined. A Normac gas analyser and a Varian 3700 gas chromatograph were calibrated against known standards of HE. The performance of two vaporizers (Fluotec Mark III, Servo vaporizer for halothane) was studied. The Fluotec Mark III vaporizer and the Servo halothane vaporizer filled with HE gave a linear performance with increasing dial settings. The Normac gas analyser set for methoxyflurane was linearly sensitive to the ether component of the azeotrope. The MAC for HE in man was 0.71 vol.% 0.03 (s.e.mean) (ether 0.21 vol.%, halothane 0.50 vol.%) in the age group 19–42 years. MAC for halothane in man was 0.65 0.03 in the age group 19–32 years. The MAC for HE in pigs between 20–24 kg was 0.99 vol.% 0.07. The ether component seems to act synergistically with halothane in the azeotropic mixture. The present study provides an opportunity to compare HE with other volatile anaesthetic a

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03271.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Interactive effects of the phosphodiesterase‐III inhibitor amrinone and isoflurane were investigated in cats. Cardiac output (thermodilution method), and intestinal (IBF) and renal (RBF) blood flows (optical flowmetry) were measured. Intestinal (IVR) and renal (RVR) vascular resistances were derived. To discriminate between pressure‐related local myogenic vascular responses and primary vascular drug effects, intestinal and renal perfusion pressures (50 mmHg; 6.7 kPa) were controlled. The protocol included steady‐state recordings with and without isoflurane in a randomized order, both before and after the administration of amrinone (2 mgkg‐1i.v. + 2 mgkg‐1i.v.). Amrinone induced no significant changes in IVR or RVR during basal chloralose anesthesia. During administration of 0.8% isoflurane, amrinone produced decreases in IVR and RVR, which were more pronounced than the vasodilator responses induced by this dose of isoflurane alone. On the other hand, with 1.6% isoflurane, amrinone did not add to the vasodilation. The cardiac effects of isoflurane and amrinone were small. Our data indicate that the vascular tone before administration of amrinone could be crucial for the vascular response of the drug and that isoflurane can significantly influence the regional circulatory effects of

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03272.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Continuous on‐line breath‐by‐breath measurement of pulmonary gas exchange was used to monitor the increase in oxygen uptake (Vo2) and carbon dioxide excretion (Vco2) induced by the oxidative phosphorylation uncoupling agent 2, 4‐dinitrophenol (DNP) in 10 dogs. With incremental doses of DNP totaling 5 mg/kg, the continuously monitored Vo2increased within 2–3 min after the first injection of the drug. Vco2showed a similar response 4–6 min after the first injection. Temperature increase due to the pharmacological oxidative phosphorylation uncoupling required 20–30 min for a discernible change at this dose. This study also demonstrated a modified and compromised response to the drug in dogs where oxygen delivery was limited by mechanica

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03273.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The effects of halothane on diazepam binding to the rat cerebral synaptic membranes were investigated. Halothane at the concentrations of 0.63, 1.3 and 4.1 mmol/1 increased the binding by 12, 23 and 33%, respectively, compared to the control in the absence of halothane. The increments were dependent on the presence of Cl. The findings indicate that halothane and diazepam have an interaction at receptor level.

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03274.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The influence of intradermal needle insertion and fluid injection on skin blood flow was investigated using laser Doppler flowmetry. Seventeen healthy, young male volunteers participated. Four test sites on each forearm (volar surface) were used in a randomized, double‐blind study. Recordings were made at 20, 40, 60 and in GroupIIIalso at 90 min after needle insertion or intradermal injection. In GroupI(n = 6) different volumes of saline (0.05, 0.1, 0.2, 0.3 and 0.5 ml) were injected, producing an increase in flow, there being no differences between the various volumes. In GroupII(n = 4) needle insertions were made using different needle sizes (20 G, 23 G and 30 G), the larger ones being impractical to use. Increases in flow were seen, and were somewhat higher for the larger needles. GroupIII(n= 12) was studied regarding the effects of three local anaesthetic agents on skin blood flow (0.1 ml, 30 G needle). Injection of bupivacaine 0.75d̀ produced a marked increase in flow, similar to lidocaine 1% but apparently longer lasting. Bupivacaine 0.25% caused less increase in flow, similar to the flow seen with saline. Injections of ropivacaine 0.75d̀ and 0.25%, i.e. in clinical concentrations, caused a decrease in blood flow, this being most marked after 0.25d̀, indicating a unique flow‐decreasing effect of this new local anaestheti

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03275.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The effects of adenosine and sodium‐nitroprusside (SNP) on central and myocardial haemodynamies and metabolism were evaluated during fentanyl anaesthesia (100 μg kg‐1) in six patients with peripheral vascular disease. The investigation was performed during stable anaeshtesia, before scheduled abdominal aortic graft surgery. Adenosine and SNP were infused intravenously in random order over 20 min, leaving a 30‐min control period in between. The vasodilators were titrated in order to reduce mean arterial pressure by approximately 25%. Adenosine (90 20 μgkg‐1min‐1) reduced mean arterial pressure from 10.9 0.3 to 8.4 0.4 kPa (82 3 to 63 3 mmHg), and SNP (0.7 0.1 μg kg‐1min‐1) from 11.0 0.2 to 8.4 0.3 kPa (83 3 mmHg to 63 3 mmHg) during the hypotension period. Cardiac index remained unaffected during induced hypotension with both vasodilators, while heart rate increased during SNP infusion (8 3d̀) and remained unaffected with adenosine. Left ventricular stroke work index and myocardial oxygen consumption decreased during SNP infusion (33 3% and 17 5%, respectively), while these parameters were unchanged with adenosine. Adenosine hypotension increased coronary sinus flow 1–2 fold (128 26%), together with increased coronary sinus oxygen content (96 11%). In contrast, coronary sinus flow decreased during SNP hypotension (– 15 4%) with unaffected coronary sinus oxygen content. It is concluded that adenosine, in contrast to SNP, is associated with a hyperkinetic m

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03276.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Sufentanil has so far seldom been used for intravenous postoperative patient‐controlled analgesis (PCA), and the resulting serum concentrations have not yet been determined. Forty ASA I‐III patients recovering from major gynecological operations were investigated to evaluate analgesic efficacy, side effects, patient acceptance and threshold concentrations of sufentanil in serum during the early postoperative period, using the On‐Demand Analgesia Computer (ODAC). Following an individualized intravenous loading dose of 19.1 35.7 μg (mean 1 s.d.), sufentanil demand doses were 6 μg with a concurrent infusion of 1.15 μg/h and a maximum hourly dose of 40 μg/h; the lockout time was set to 1 min. The duration of PCA was 17.3 2.1 h. During this time 16 11 demands per patient were recorded, resulting in an average sufentanil consumption of 131.1 69.4 μg or 7.5 3.7 μg/h (including loading dose). Analgesia was mostly judged good. Side effects were only of minor intensity. Sufentanil proved to be about 2.2 to 3.8 times as potent an analgesic as fentanyl when both analgesic effect and duration were considered. Minimum effective sufentanil serum concentration (MEC) as determined by radioimmunoassay varied greatly and could be best described by a log‐normal distribution (range<0.01–0.56 ng/ml, median 0.024 ng/ml). Intraindividual MEC variability was slightly lower than intersubject variability (76.0 vs. 84.8%). It is concluded that sufentanil is suitable for postoperative PCA. To get into the therapeutic window for analgesia, a serum sufentanil concentration of more than 0.03 ng/ml seems

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03277.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Assessing the adequacy of anesthesia in the paralyzed patient is usually based on sympathetic and hemodynamic responses to noxious stimulation. Absence of such responses does not guarantee adequate anesthesia. A device monitoring the amplitude of provoked lower esophageal, contractility (PLEC) and the rate of spontaneous lower esophageal contractility (SLEC) has been developed as a potential monitor of the adequacy of anesthesia. This study determined the reliability of this device for monitoring anesthetic depth in 20 patients receiving fentanyl infusions who were undergoing coronary artery surgery and who were hemodynamically stable in the preoperative period. Premedication included midazolam 0.05 mg/kg i.m. and ranitidine 2 mg/kg p.o. Anesthesia was induced with fentanyl 50 μg/kg administered over 10 min and maintained by a fentanyl infusion 0.2 μgkg‐1min‐1. Following endotracheal intubation, a disposable esophageal monitoring probe, equipped with provoking and measuring balloons, was inserted and both the amplitude of provoked (PLEC) and the rate of spontaneous lower esophageal contractions (SLEC) were displayed and recorded. Precisely defined clinical signs of inadequate anesthesia included both somatic and hemodynamic responses to noxious stimulations. The presence of these responses was correlated with PLEC and SLEC and with fentanyl concentrations in plasma at specific times of noxious stimulation during the period preceding initiation of cardiopulmonary bypass. A total of 208 episodes of noxious stimulation were recorded at insertion of the nasal temperature probe (n = 8), at penetration of the skin by towel clips (n = 25), at skin incision (n = 20), at sternotomy (n = 20) and during multiple episodes of electrocauterization (n = 135). These provoked 52 clinical responses. The rate of the spontaneous contractions at times of response (4.5 4.6 contractions per 3 min, mean s.d.) was significantly greater than that at times of no response (2.5 2.7 contractions per 3 min;P0.05). The most favorable cut‐off point was determined to be a rate of 3 contractions per 3‐min period. This produced a false positive rate of 41.7% and a sensitivity (true positive rate) of 59.6%. There was no clear relationship between plasma concentrations of fentanyl and the rate of spontaneous contractions, or hemodynamic or somatic response to stimulation. We conclude that monitoring lower esophageal contractility is not reliable for detection of inadequate opioid a

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03278.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Pneumoperitoneum following cardiopulmonary resuscitation (CPR) results from a thoracic air leak (pneumothorax, pneumomediastinum) with escape of the air through diaphragmatic apertures (mostly foramen of Winslow) or primary perforation of the gastrointestinal tract (stomach or esophagus). We report three cases of pneumoperitoneum complicating CPR. As there was no clinical evidence of peritonitis, and the patients remained stable, a conservative approach was followed without surgical exploration. All patients recovered completely.

ISSN:0001-5172    

DOI:10.1111/j.1399-6576.1991.tb03279.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY