ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The authors determined the pharmacokinetics and duration of action of a bolus dose of pipecuronium bromide (0.07 mg.kg-1) in 40 patients anesthetized with halothane and nitrous oxide. Twenty were patients with normal renal function, undergoing a variety of surgical procedures, and 20 were undergoing cadaver renal transplantation because of end-stage renal disease. Plasma concentrations of pipecuronium were measured for 6 h after administration using a sensitive and specific capillary gas chromatographic assay. Plasma concentrationversustime data were analyzed by nonlinear regression and fit to a two-compartment or three-compartment model; in addition, the data were analyzed by a non-compartmental method based on statistical moments. Neuromuscular blockade was assessed by measuring the mechanical evoked response of the adductor pollicis muscle to train-of-four stimulation of the ulnar nerve. The pharmacoinetic parameters derived by compartmental modelling were (normalvs. renal failure, respectively): volume of distribution at steady state (309 ± 103vs. 442± 158 ml. kg-1, mean ± SD), plasma clearance, (2.4 ± 0.6vs. 1.6 ± 0.6 ml.kg-1.min-1), mean residence time (140 ± 63vs. 329 ± 198 min-1), and elimination half-life (137 ± 68vs. 263 ± 168 min). The same parameters as derived by the non-compartmental method were (normalvsrenal failure, respectively): volume of distribution at steady state (307 ± 80vs. 426 ± 119 ml.kg-1, mean ± SD), plasma clearance (2.4 ± 0.6vs. 1.6 ± 0.6 ml.kg-1. min-1), mean residence time (134 ±41vs. 323 ± 228 min), and elimination half-life (118 ± 35vs. 247 ± 168 min). All these pharmacokinetic parameters differed significantly between the patients with normal renal function and those with renal failure (P< 0.05). Despite the pharmacokinetic differences, the mean duration of action (injection to 25% recovery of twitch tension) of pipecuronium was similar in both groups (98 ± 36 min, normal, and 103 ± 60 min, renal failure, mean ± SD). However, the duration of action of pipecuronium in patients with renal failure (range 30–167 min) was more variable than in those with normal renal function. (range 55–198 min). This unpredictable response, with the possibility of prolonged blockade, suggests pipecuronium may be less suitable for use in patients with renal failure than the neuromuscular blocking drugs, vecuronium and atracurium, which have a shorter and a more predictable duration of action in these patients.

ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Lower intercostal and abdominal muscles interact with other respiratory muscles to produce inspiration as well as expiration. Intercostal nerve blockade from T6-T12was produced in seven healthy males to study its effect on: 1) supine pulmonary function, 2) inspiratory effort, 3) hypercapnic ventilatory response, including mouth occlusion pressures with and without an expiratory load, and 4) ventilation during progressive exercise on a cycle ergometer. Studies during control and blocked states were performed on different days. Lower chest and abdominal wall paralysis was documented with electromyography. Findings include a minimal decrease in peak expiratory flows with intercostal blockade (P= 0.02), but no other changes in supine resting pulmonary function tests, inspiratory effort, or hypercapnic ventilatory response slopes. Minute ventilation, respiratory rate, and VT/TIduring exercise were also minimally increased, indicating an increase in the drive to breathe, which was unrelated to a change in metabolic rate. During exercise, total time to exhaustion was decreased following intercostal nerve blockade. Bilateral intercostal nerve blockade produced minimal decreases in peak expiratory flow at rest in supine subjects. During seated exercise, there was a slight increase in respiratory drive, probably due to minor alterations in the mechanics of breathing induced by intercostal blockade. The authors conclude that, in healthy young subjects, intercostal nerve blockade does not exert a clinically significant adverse affect on pulmonary mechanics and that ventilatory function is well-maintained even at extremes of ventilatory demand.

ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

To compare mechanical, electrocardiographic, and metabolic indices of myocardial ischemia, the cardiokymogram (CKG), the V5ECG, left anterior descending coronary artery territory lactate extraction, and pulmonary capillary wedge pressure (PCWP) were measured in 53 vascular surgical patients with coronary artery disease. Measurements were performed preoperatively and at four specific intraanesthetic intervals after tracheal intubation, before surgery, and 10 and 30 min after incision. Measurements and sampling sequence took 5–7 min, and therapy for the probable cause of ischemia was instituted following completion of this sequence. Myocardial ischemia was defined as type II or III CKG, 0.1 mV or greater horizontal or downsloping depression of V5ECG ST segment, 0.2 mV or greater elevation of V5ECG ST segment, or myocardial lactate production. Thirty-nine patients (74%) had a total of 89 episodes of myocardial ischemia. Seventy-four episodes (83%) were detected by the CKG, 31 (44%) were evident on the ECG, and 13 (15%) by evidence of lactate production. The concordance among the indices of myocardial ischemia was poor. Patients with an abnormal preoperative ECG experienced a greater number of ischemic episodes (P< 0.001). Elevation of PCWP or the presence of A-C or V-waves greater than 5 mmHg above the mean did not individually reflect ischemia reliably. Intraoperative myocardial ischemia is common in vascular surgical patients and is most sensitively detected by ventricular wall motion abnormality.

ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The purpose of this study was to examine the doseversusEEG response relationship, the speed of onset, and the thiopental requirement for induction of anesthesia with small doses of sufentanil and fentanyl. The power spectrum of the electroencephalogram (EEG) was used to quantify the effect of the opioids. Eighty male surgical patients, 52–80 yr old, were randomly divided into eight groups of ten to receive fentanyl, 5, 7, 10, or 13 μg/kg, or sufentanil, 0.5, 0.7, 1.0, or 1.3 μg/kg. The opioid was given iv over 1 min at a constant rate of infusion. Three to four minutes after the start of the opioid dose, thiopental was given iv in 25 mg increments every 30 s until the patient was unconscious. Power in the 1–3 Hz band reached maximum levels in less than 4 min after the start of opioid administration. At fentanyl doses of 7.0 μg/kg or less, or sufentanil doses of 1.0 μg/kg or less, the EEG effects did not increase in proportion to the dose of opioid. There was not a significant difference in the maximum power achieved in the 1–3 Hz band for sufentanil, 0.5, 0.7 and 1.0, and fentanyl, 5 and 7 μg/kg. Doses of fentanyl, 10 or 13 μg/kg, or sufentanil, 1.3 μg/kg were substantially more effective; the maximum power increased significantly between 7 and 10 μg/kg of fentanyl and 1.0 and 1.3 μg/kg of sufentanil (P< 0.0001). The potency of sufentanil and fentanyl were compared by superimposing, the doseversusresponse (power) curves. The potency ratio was 1:8 (sufentanil:fentanyl). Speed of onset (T50) was determined from the time required to reach 50% of the maximum power in the 1–3 Hz band. Mean T50 was similar for sufentanil, 0.5, 0.7, and 1.0 μg/kg (132 ± 21 s, including the 60 s drug injection) and fentanyl, 5 and 7 μg/kg (132 ± 20 s). Mean T50 was significantly less (P< 0.0001) for sufentanil, 1.3 μg/kg (92 ± 22 s) compared with that following an equipotent dose of fentanyl, 10 μg/kg (112 ± 18 s). The thiopental dose requirement was inversely related to the dose of opioid and was less for sufentanil compared with fentanyl. Nine of ten patients receiving 1.3 μg/kg sufentanil did not require thiopental to produce unconsciousness.

ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The dose-response relationships of mivacurium chloride during N2O/fentanyl or N2O/enflurane anesthesia were compared in 70 patients intraoperatively. Responses were defined in terms of percentage changes in the evoked twitch tension of the adductor pollicis muscle, and dose-response curves were constructed following probit transformation of the responses. End-tidal concentrations of enflurane during the were study were 0.9–1.2%. When compared with the dose-response curve determined during N2O/fentanyl anesthesia the curve determined during N2O/enflurane anesthesia was displaced significantly to the left (P< 0.05). As a result, the doses of mivacurium that depressed twitch tension by 50% (ED50) and 95% (ED95) were 39 and 67 μg/kg, respectively, during N2O/fentanyl anesthesia, and 27 and 52 μg/kg during N2O/enflurane anesthesia. Regression lines describing the relationship between the maximum depression of twitch tension (response) and the time interval between the injection of mivacurium and the return of twitch tension to 90% of the control value (duration) were constructed. The response-duration line for N2O/enflurane anesthesia was displaced significantly to the left of the line for N2O/fentanyl (P< 0.05), indicating that enflurane anesthesia was associated with a prolongation of mivacurium-induced neuromucular blockade. The neuromuscular blocking effect of mivacurium is both enhanced by and prolonged during N2O/enflurane compared with that during N2O/fentanyl anesthesia.

ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

Complications of transurethral resection of the prostate (TURP syndrome) when glycine is used as the irrigating fluid include cardiovascular and central nervous system abnormalities that occasionally include transient blindness. Serum sodium, glycine, potassium, chloride, ammonia, osmolality, carbonate, and blood urea nitrogen of 17 patients having TURP and 10 having cystoscopic examination were measured. Electroretinograms and visually evoked potentials (VEPs) were recorded in the preanesthetic preparatory area and in the recovery room immediately after surgery. Four patients reported visual aberrations coincident with increases in serum levels of glycine from a mean before surgery of 137.7 ± 45.1 to 7,812.2 ± 2,486.6 μM/1, mean ± SD, after TURP. These patients also showed a reduction of serum sodium from 138 ± 4.5 to 122 ± 8.6 mEq/I that correlated significantly with serum levels of glycine (rho = −0.81). There were no statistically significant changes of serum ammonia and osmolality. Electroretinograms consistently demonstrated complete loss of oscillatory potentials. Thirty hertz flicker-following was also abolished. VEPs were more variably affected with prolongation of component “P100‘’ latency found in both groups and probably resulting from sedative effects of diazepam. Patients experiencing the TURP syndrome showed abolishment of 30 Hz flicker-following in their VEPs. The elevated serum levels of glycine may contribute directly to visual aberrations resulting from glycine's role as an inhibitory transmitter in the retina.

ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID

摘要:

The frequency of spontaneous lower esophageal contractions (SLEC) has been proposed as one measure of anesthetic depth. The authors tested the hypothesis that SLEC frequency can predict movement in response to skin incision during halothane or nitrous oxide/alfentanil anesthesia. The incidence of movement during skin incision was compared with the frequency of spontaneous lower esophageal contractions in 20 healthy patients anesthetized with halothane. Esophageal contractility was determined using the Lectron 302, which senses the pressure in a water-filled balloon positioned in the distal esophagus. Absence of SLEC in the 6 min preceding incision correlated with no movement, with one exception (n = 9). All but one patient having ≥ 2 SLEC in the 6 min preceding skin incision moved (n = 8) (P< 0.01). Sixteen additional patients anesthetized with nitrons oxide (70%) and alfentanil demonstrated no correlation between SLEC frequency and movement. These data suggest that the frequency of spontaneous lower esophageal contractions, and its ability to predict movement, depends on anesthetic type.

ISSN:0003-3022    

出版商:OVID    

年代:1989

数据来源: OVID