Search PubMed⌕ Search

Biomedical subjects

J M Garfield

Publications and source records attributed to J M Garfield.

At least 19 recordsLinked to original sources
PubMed1996

Propofol and ethanol produce additive hypnotic and anesthetic effects in the mouse.

The sedative and anesthetic effects of ethanol and propofol when these drugs are coadministered are not known. Accordingly, we investigated the nature of the pharmacological interaction between ethanol and propofol during hypnosis and anesthesia in the mouse. Propofol, ethanol, and mixtures of the two were administered through the tail vein in male CD-1 mice (n = 162). The loss of righting response occurring 10 s after injection and persisting at least 10 s thereafter was defined as hypnosis, and lack of a motor response to tail clamping 60 s after injection was defined as anesthesia. The 50% effective dose (ED50) values for the hypnotic and anesthetic actions of the drugs were determined with quantal dose-response curves, using probit analysis. The pharmacological interactions were identified by the locations of ED50 values on their corresponding hypnosis and anesthesia isoboles. For each drug alone, the hypnotic and anesthetic ED50 values with 0.95 confidence intervals were 16.70 (11.98, 23.20) mg/kg and 25.02 (20.27, 31.29) mg/kg for propofol and 0.88 (0.81, 0.95) g/kg and 1.80 (1.45, 2.23) g/kg for ethanol, respectively. For the drugs in combination, the ED50 values for hypnosis with 0.95 confidence intervals were 6.98 (6.50, 7.49) mg/kg propofol with 0.61 (0.57, 0.66) g/kg ethanol, and for anesthesia were 10.55 (9.76, 11.42) mg/kg propofol with 0.93 (0.86, 1.05) g/kg ethanol, respectively. When plotted isobolographically, we found these combinations to be behaviorally additive both for hypnosis and anesthesia. Although a finding of synergism would have excluded the possibility of an identical mechanism of action for the drugs, elucidation of the molecular basis of the additivity must await further studies.

Anesthetics, Intravenous↗
PubMed1993

The effect of operative technique and uterine size on blood loss during myomectomy: a prospective randomized study.

OBJECTIVES: To compare operative blood loss between two accepted blood loss-reducing techniques used during myomectomy and to evaluate the effect of preoperatively determined uterine volume on blood loss. DESIGN: Subjects were stratified by ultrasound-determined uterine volume < 600 cm3 (n = 11) and > or = 600 cm3 (n = 10) and then randomized into treatment groups. The same radiologist, surgeons, and anesthetic induction technique were involved in every case. In the pharmacologic technique, diluted vasopressin (20 U in 20 mL normal saline) was injected into the serosa and/or myometrium overlying the fibroid(s) before the uterine incision(s). In the mechanical technique, a penrose drain tourniquet was passed through defects created in the broad ligaments at the level of the internal os and secured posteriorly, occluding the uterine vessels. In addition, vascular clamps were placed on the infundibulopelvic ligaments, occluding anastomotic blood flow through the ovarian vessels. RESULTS: There was no difference in operative blood loss, operating time, preoperative and intraoperative mean arterial blood pressures, postoperative febrile morbidity, preoperative and postoperative hematocrits, transfusion rates, and length of hospital stay between groups. Blood loss was significantly greater for uteri with ultrasound-determined volumes > or 600 cm3 (627 +/- 175 mL, mean +/- SEM) than for those < 600 cm3 (228 +/- 49 mL). For all subjects, blood lost while operating on the uterus (mean, 379 mL; range, 35 to 1,968 mL) was positively correlated with the total weight of the fibroids resected and with time spent operating on the uterus. Total blood loss (mean, 418 mL; range, 42 to 1,968 mL) was also positively correlated with the time spent operating on the uterus and with total operating time. CONCLUSIONS: There were no demonstrable differences in blood loss, morbidity, or transfusion requirements between subjects undergoing myomectomy using pharmacologic vasoconstriction and mechanical vascular occlusion techniques. Blood loss during myomectomy is primarily incurred while operating on the uterus and is correlated with preoperative uterine size, total weight of fibroids removed, and operating time.

Adult↗
PubMed1990

Anesthetic considerations for gynecologic cancer surgery.

Preoperative, intraoperative, and postoperative anesthetic considerations in gynecologic cancer surgery are discussed. Preoperatively, the anesthetist must document the patient's disease state, physical condition, responses to prior chemotherapeutic regimens and toxic side effects, particularly from Adriamycin and bleomycin. Laboratory studies should include electrolytes, hepatic, renal, and hematologic indices. The anesthetist should also recognize that patients may be under great emotional stress, which may require prescribing anti-anxiety medications for several days prior to surgery. Planning the anesthetic includes consultation with the surgeon relative to procedure planned, positioning requirements, anticipated blood loss, monitoring and postoperative care requirements. Intraoperative considerations again involve close communication with the surgeon. The use and benefits of a combined regional/general anesthetic technique are discussed. Postoperative considerations are directed toward hemodynamic stability and control of postoperative pain. Techniques of epidural narcotic and local anesthetic administration, as well as patient-controlled analgesia (PCA) are discussed.

Anesthesia, Conduction↗
PubMed1989

A comparison of two microcomputer-based programs for bibliographic retrieval and formatting.

We evaluated two representative microcomputer-based programs for organizing a biomedical literature filing system. With a bibliography of 100 anesthetic references, a series of benchmark tests was developed to measure the speed and accuracy of typical searching, sorting, and formatting tasks. Each program performed the searching tasks accurately and at about the same speed. One program performed sorting without errors, provided the field order of the template used to enter references was unchanged. Both programs used "punctuation files," that is, templates for controlling author presentation; punctuation to suit style requirements of individual journals; and order of particular fields, such as publisher and year of publication. Each program was able to format journal, book, and chapter references correctly, but the resulting output required some refining in a word processor. Both require a major time commitment to learn and to create custom punctuation files for journals not included in the predesigned punctuation files. Once mastered, both programs are quite competent at organizing reprints and formatting journal references.

Humans↗
PubMed1989

An evaluation of the effectiveness of a computer simulation of anaesthetic uptake and distribution as a teaching tool.

Gas Man is an interactive, microcomputer-based simulation and tutorial designed to teach the principles of anaesthetic uptake and distribution. Using two resident groups, one at a primary university-teaching hospital and the other at a medical school affiliated community hospital, the authors compared residents' knowledge of the subject prior to exposure to the tutorial and the average time spent using the program during a self-paced instruction period. Both groups not only significantly improved their knowledge of uptake and distribution 8 weeks after using this program, but wished to spend additional time with it, implying that it was a pleasant and satisfying way to learn. Computer simulation has the potential to be an important teaching tool in an anaesthesia residency training programme.

Anesthesiology↗
PubMed1989

A randomized, placebo-controlled, double-blind study evaluating leuprolide acetate depot treatment before myomectomy.

Eighteen premenopausal women with symptomatic leiomyomata uteri were enrolled in a stratified, randomized, double-blind, placebo-controlled study evaluating the efficacy of leuprolide acetate (LA) depot treatment before myomectomy. Stratification was based on pretreatment uterine volume (less than 600 cm3 versus greater than or equal to 600 cm3). Nine women received intramuscular (IM) depot LA 3.75 mg every 4 weeks for 12 weeks (group A); nine women received IM placebo with the same injection schedule (group B). All women underwent myomectomy within 4 weeks of their last injection. Mean total intraoperative blood loss was 213 +/- 44 mL (mean +/- standard error of the mean [SEM]) in group A and 302 +/- 43 mL in group B. When data from patients with large uteri (pretreatment uterine volumes of 600 cm3 or greater) were analyzed, mean total blood loss was 189 +/- 44 mL in group A and 390 +/- 20 mL in group B. These data suggest that leuprolide depot treatment before myomectomy may decrease intraoperative blood loss in women with large leiomyomata uteri.

Delayed-Action Preparations↗
PubMed1987

A comparison of clinical and psychological effects of fentanyl and nalbuphine in ambulatory gynecologic patients.

Drug dosages, length of stay (LOS), and incidence of psychological side effects of fentanyl and nalbuphine were compared in a randomized, double-blind study using unpremedicated female day-surgery patients undergoing diagnostic laparoscopy. Patients received either fentanyl 1.5 micrograms/kg (F group; n = 142), low-dose nalbuphine 300 micrograms/kg (LN group; N = 103), or high-dose nalbuphine 500 micrograms/kg (HN group; n = 41), intravenously (IV) before anesthesia consisting of thiopental, N2O, O2, and a succinylcholine infusion. Additional IV intraoperative and IM postoperative opioids were given if required for signs of inadequate anesthesia or postoperative pain. The patients' clinical and psychological status was evaluated at 20-min intervals postoperatively by a team of trained interviewers. The low- and high-dose nalbuphine groups clinically resembled the fentanyl group in terms of dosing frequency and patients' self-ratings of postoperative analgesia. Length of stay and postoperative sedation were significantly greater with nalbuphine. The incidence of psychological side effects, including dreaming and postoperative anxiety, was also greater with nalbuphine. However, patient acceptance of nalbuphine was high and was similar to that observed in patients given fentanyl.

Ambulatory Care↗
PubMed1985

Differential effects of ketamine stereoisomers on maze performance in the mouse.

The authors studied effects of subanesthetic doses of the d- and l-ketamine stereoisomers on maze performance in mice to determine whether the stereoisomers differed in their ability to disrupt a stable cognitive behavior. Twenty-four Swiss-Webster (CFW) mice were trained to stability in a four-compartment modular maze, using water as a reward. Each compartment contained a central partition with a barrier at the distal end of one of the two passageways. A fixed barrier-sequence was employed. Elapsed time to traverse all four compartments and total number of errors (the number of times a wrong compartment was entered) were measured. A cohort design was employed with the following four groups: saline control, d-ketamine, l-ketamine, racemate. Two subanesthetic doses, 7.5 and 15 mg/kg of each form of the drug were given subcutaneously at five-day intervals. Both the d-isomer and the racemate significantly prolonged elapsed time at 15 mg/kg, the d-isomer having the greatest effect. The l-isomer did not alter elapsed time at either dose but appeared to increase spontaneous locomotor activity after injection. Relative to errors, at the 7.5 mg/kg dose there were no changes from control with any form of ketamine. However, at the 15 mg/kg dose, total errors significantly increased both with the racemate and the d-isomer. The performance decrements observed with the racemate appear to be attributable largely to the d-component.

Animals↗
PubMed1985

Comparative acceptance of three transdermal nitroglycerin placebo patches.

Factors that might affect patient acceptance of transdermal drug-delivery system patches were evaluated in healthy volunteers using placebo patches. Placebo transdermal nitroglycerin patches (Transderm-Nitro 5 placebo, Ciba Pharmaceutical Company; Nitro-Dur 10 cm2 placebo, Key Pharmaceuticals; and Nitrodisc 5 placebo, Searle Laboratories) were supplied by the manufacturers. Eighty-two healthy subjects were randomly assigned to begin using one of the three brands of patches. Using a Latin-square crossover design, subjects applied each brand of patch daily for five days and crossed over to the other brands on study days 6 and 11. At the end of each study phase, subjects completed a written questionnaire designed to evaluate their overall acceptance of each brand of patch. A total of 80 subjects completed all three phases of the study. According to forced rank preference, 84% of subjects preferred the Ciba patch to one of the other two brands. Subjects judged the Ciba patch to be the easiest of the three brands to use and reported significantly fewer side effects and skin irritation while using the Ciba patch; they also preferred the size of the Ciba patch and experienced significantly fewer problems with adherence of the Ciba patch. A significant percentage of subjects indicated that they would prefer a transdermal patch over tablets or ointment. Most subjects preferred the Ciba patch over the Key patch or Searle patch.

Adhesiveness↗
PubMed1975

Effects of nitrous oxide on decision-strategy and sustained attention.

Effects of 10,20, and 30% N2O on decision-making strategy, reaction-times, sustained attention, the Digit Symbol Subsititution Test (DSST), short-term memory and the Clyde Mood Scale were assessed in 12 test subjects. Decision-making strategy, as measured by 2-choice probability-learning, was unaffected by 30% N2O once a strategy had been formulated, but reaction-times were increased. Sustained attention was significantly affected in 33% of our subjects, whereas performance on the DSST and on the short-term memory task was impaired in virtually all subjects. Changes were noted in several mood-scale factors with 30% N2O. No residual drug effects were found.

Adolescent↗