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D A Scott

Publications and source records attributed to D A Scott.

153 records · Page 9Linked to original sources

Cholesterol vehicle in experimental atherosclerosis. Part 18. Comparison of North American, African and South American peanut oils.

Peanut oils were obtained from the United States (NAPNO), Africa (APNO), and South America (SAPNO) and their effects on atherosclerosis in rabbits fed 2% cholesterol were determined. The major differences among the oils were in the content of oleic (NAPNO, 48.9%; APNO, 58.6%; SAPNO, 36.4%) and linoleic (NAPNO, 29.6%; APNO, 21.7%; SAPNO, 41.1%) acids. In a series of 4 experiments it was found that South American peanut oil was 7% more atherogenic than African peanut oil and 18% more atherogenic than North American peanut oil. American peanut oil was 14% more atherogenic that corn oil (CO). South American peanut oil gave highest serum and liver lipid levels. The differences in atherogenicity may be due to the structure of the triglycerides of the various peanut oils.

Africa↗

A seroepidemiological survey of viral hepatitis in the Yemen Arab Republic.

During February 1988 a seroepidemiological survey of hepatitis A, B and D was performed in the Yemen Arab Republic. 879 sera were collected from 4 different areas; Sanaa, Hajja, Hodeidah and Taiz. The prevalence of hepatitis B surface antigen (HBsAg) was 12.7% (112/879) and some marker of hepatitis B infection was found in 45.5% (399/879) of study subjects. Only 2 (1.8%) of the 112 HBsAg positives were positive for antibody to delta hepatitis, and 9.7% (9/93) were positive for hepatitis B e antigen (HBeAg). Univariate analysis showed age, sex, qat chewing, blood transfusion, surgery and a past history of jaundice to be associated with hepatitis B infection. Using multivariate logistic regression analysis only, age (odds ratios 1.37 for HBsAg carriers and 1.51 for seropositives), a past history of jaundice (odds ratio 1.42), and combined history of blood transfusion and surgery (odds ratio 2.76) were independent predictors of infection. Hepatitis B appears to be a major health concern in the Yemen Arab Republic.

Adult↗

Comparison of clonidine and epinephrine in lidocaine for cervical plexus block.

BACKGROUND AND OBJECTIVES: Carotid endarterectomy under cervical plexus block offers the advantage of awake neurologic assessment. The hypothesis was tested that the addition of clonidine 5 micrograms/mL to lidocaine 1.5% for the block is as effective clinically as the addition of epinephrine 5 micrograms/mL but without the associated tachycardia. METHODS: In a double-blind, randomized, prospective trial of 40 patients, local anesthetic solutions of lidocaine 1.5% containing either clonidine 5 micrograms/mL or epinephrine 5 micrograms/mL were compared for cervical plexus block in patients undergoing carotid endarterectomy. Each solution was administered to 20 patients with a total lidocaine dose of 7 mg/kg. The electrocardiogram, heart rate, and arterial pressure (radial artery catheter) were continuously monitored. Blood samples were drawn for determination of serum lidocaine levels during the first hour. RESULTS: The block onset time (8.4 +/- 0.6 minutes for epinephrine, 8.8 +/- 0.8 minutes for clonidine) and duration (139 +/- 6.7 minutes for epinephrine, 148 +/- 5.8 minutes for clonidine) were not different between the two groups. During the period from completion of the block until incision there was a significant heart rate increase in the epinephrine group (23% mean rise) as compared with the clonidine group (4% mean rise) (P < .003). There was no difference in blood pressure between the two groups. The maximum plasma concentrations of lidocaine were 2.5-7.6 micrograms/mL (mean, 4.5 +/- 0.3 micrograms/mL) for the epinephrine group and 4.7-18.4 micrograms/mL (mean, 7.5 +/- 0.7 micrograms/mL) for the clonidine group (P < .0002). The maximum concentrations were reached 0-30 minutes (mean, 8 +/- 1.4 minutes) after injection for the epinephrine group and 0-10 minutes (mean, 4.5 +/- 7.1 minutes) for the clonidine group (P < .03). CONCLUSIONS: Clonidine 5 micrograms/mL is a useful additive to lidocaine 1.5% for cervical plexus block to reduce the incidence of tachycardia; however, omission of epinephrine results in higher serum lidocaine levels.

Adrenergic alpha-Agonists↗

Continuous axillary brachial plexus block for postoperative pain relief. Intermittent bolus versus continuous infusion.

BACKGROUND AND OBJECTIVES: The aim of this study was to compare the efficacy and safety of continuous axillary brachial plexus block by infusion and by intermittent injection of bupivacaine 0.25% in the management of postoperative pain. METHODS: Two methods of continuous axillary brachial plexus block for pain management were compared in a prospective randomized trial. Twenty 16- to 62-year-old male patients (ASA I and II), undergoing microsurgery, received 0.25% bupivacaine following surgery, by either continuous infusion (group C, n = 10), or intermittent hourly bolus (group B, n = 10), via an axillary brachial plexus catheter inserted prior to operation. Efficacy assessments and analysis of plasma bupivacaine levels were performed for up to 38 hours postsurgery. RESULTS: There was no difference between groups with respect to pain scores, degree of motor block, or supplemental narcotic requirements. Plasma bupivacaine levels were higher in group C, with the difference reaching significance after 26 hours (means +/- SEM: C = 1.03 +/- 0.10 micrograms/mL, B = 0.73 +/- 0.08 microgram/mL, P < .05). There were no significant differences in cumulative bupivacaine doses or infusion rates between the groups. Complications included one case of axillary artery puncture at insertion, two unplanned premature catheter removals, and a self-limited grand mal convulsion in a known epileptic. CONCLUSIONS: Overall, both techniques provided safe and effective postoperative analgesia. As compared with continuous infusion, intermittent bolus administration resulted in lower plasma bupivacaine levels despite similar infusion rates.

Adolescent↗

Superficial and deep cervical plexus block for carotid artery surgery: a prospective study of 1000 blocks.

BACKGROUND AND OBJECTIVES: Cervical plexus blocks are performed for carotid surgery to allow neurological assessment of the awake patient. The aim of this study was to establish the frequency of success, complications, and patient acceptance of the technique. METHODS: One thousand superficial and deep cervical blocks were performed in 924 patients having carotid artery surgery. Data about the blocks were recorded prospectively and patients were followed up postoperatively by an independent anesthesiologist to assess patient acceptance of the technique. RESULTS: Lidocaine was the most frequently used anesthetic (88%). Surgical supplementation of the blocks was required in 53% of operations. Six blocks (0.6%) had clinical evidence of intravascular injection of local anesthetic. Sedation was required in 66% of operations and conversion to general anesthesia occurred in 25 (2.5%) of operations. Ninety-one percent of patients reported no problems with the block, and 93% stated that they would have the same anesthetic for any future similar surgery. CONCLUSIONS: We conclude that superficial and deep cervical plexus block has a high success rate, low complication rate, and high patient acceptance rate. Caution should, however, be exercised to ensure a low intravascular injection rate which is of most concern with this technique, because blood was aspirated in 30% of patients during performance of the block.

Aged↗