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Biomedical subjects

J D Baker

Publications and source records attributed to J D Baker.

At least 37 records · Page 2Linked to original sources
PubMed1998

Pharyngeal flap necrosis as a cause of airway obstruction during induction of anesthesia.

Anesthesiologists should approach the airway carefully in the patient with a diagnosis of head and neck carcinoma, particularly if the patient has had previous surgery and reconstruction. Patients with head and neck carcinoma may be difficult intubations due to altered anatomy from the tumor or fibrotic changes because of radiation therapy. Our patient had had pharyngectomy and reconstruction with a pectoralis major skin flap. The patient returned to the operating suite for wide-excision pharyngectomy and had acute airway obstruction after induction of general anesthesia. The pectoralis flap had necrosed, pulling away from the pharyngeal wall and obstructing the patient's glottic opening.

Aged↗
PubMed1997

Asymptomatic carotid artery stenosis screening in patients with lower extremity atherosclerosis: a prospective study.

Eighty-nine male veterans presenting to a vascular surgery clinic with symptomatic lower extremity atherosclerosis were prospectively screened by duplex scan for asymptomatic carotid artery stenosis (CAS). Their chief complaint was: claudication (90%), rest pain (6%), and ischemic ulcer or gangrene (4%). The mean ankle-brachial index (ABI) was 0.77. Twenty-five CAS > 50% were detected in 18 (20%) patients. Twelve CAS > 75% were detected in 11 (12%) patients. There was no difference between patients with and without CAS > 50% with regards to mean ABI, history of angina, diabetes, hypertension, prior coronary artery bypass, or history of smoking. Carotid bruit was associated with ipsilateral CAS > 50% [p < 0.0001, sensitivity (52%), specificity (88%), positive predictive value (41%), negative predictive value (92%)]. As a result of the screening, eight elective carotid endarterectomies have been performed to date in six (7%) patients with one transient twelfth cranial nerve paresis as the only postoperative complication. We conclude that: (1) male patients presenting with symptomatic lower extremity atherosclerosis have a 20% prevalence of asymptomatic CAS > 50%, (2) there is no correlation between the degree of lower extremity ischemia and CAS > 50%, (3) carotid bruit is significantly associated with CAS > 50%, but has a low sensitivity, and (4) routine CAS screening should be considered for all male patients with symptomatic lower extremity atherosclerosis regardless of whether a bruit is present.

Aged↗
PubMed1997

Strategies for teaching clinical decision-making.

Nursing today requires clinicians who are autonomous decision-makers. It is therefore essential that nurses develop effective problem-solving and decision-making skills. The authors have found, both in practice and in searches of the literature, that registered nurses (RNs) appear to lack the skills necessary to make effective decisions. RNs demonstrate a propensity to stereotype, to be influenced by cultural bias and a desire to make rapid decisions. The literature abounds with research into and discussion on clinical decision-making. It fails however, to specify the skills required and to delineate the educational strategies that may be employed to improve the process of making decisions. An educational program developed by the authors indicates that it is possible to facilitate the development of cognitive skills in clinical decision-making. This paper explores views expressed in the literature, as well as examining the skills developed within the program that have been found to enhance decision-making. Finally, educational strategies designed to improve these skills are discussed.

Clinical Competence↗
PubMed1997

Recommended standards for reports dealing with lower extremity ischemia: revised version.

Recommended standards for analyzing and reporting on lower extremity ischemia were first published by the Journal of Vascular Surgery in 1986 after approval by the Joint Council of The Society for Vascular Surgery and the North American Chapter of the International Society for Cardiovascular Surgery. Many of these standards have been accepted and are used in the current literature on peripheral arterial occlusive disease. With the passage of time, some oversights, aspects that require clarification, and better modifications have been recognized. This report attempts to correct these shortcomings while reinforcing those recommendations that have proven satisfactory. Explanatory comments are added to facilitate understanding and application. This version is intended to replace the original version.

Acute Disease↗
PubMed1997

Disruption of a behavioral sequence by targeted death of peptidergic neurons in Drosophila.

The neuropeptide eclosion hormone (EH) is a key regulator of insect ecdysis. We tested the role of the two EH-producing neurons in Drosophila by using an EH cell-specific enhancer to activate cell death genes reaper and head involution defective to ablate the EH cells. In the EH cell knockout flies, larval and adult ecdyses were disrupted, yet a third of the knockouts emerged as adults, demonstrating that EH has a significant but nonessential role in ecdysis. The EH cell knockouts had discrete behavioral deficits, including slow, uncoordinated eclosion and an insensitivity to ecdysis-triggering hormone. The knockouts lacked the lights-on eclosion response despite having a normal circadian eclosion rhythm. This study represents a novel approach to the dissection of neuropeptide regulation of a complex behavioral program.

Animals↗
PubMed1997

Phenomenography: an alternative approach to researching the clinical decision-making of nurses.

In this paper, the limitations associated with current research approaches to the study of clinical decision-making are discussed. Research examining the clinical decision-making of nurses and doctors, and associated work in information procession, is reviewed. It is concluded that although the research is valuable in furthering the understanding of clinical decision-making, there are limitations associated with the current research approaches. The limitations are primarily related to the research approaches employed and the concentration on experienced nurses. The research fails to examine the development of clinical decision-making ability and the learning that occurs in practice. Phenomenography is proposed as an alternative approach. The aim of phenomenography is to describe an individual's perception of a phenomenon. Phenomenography is relevant to the study of clinical decision-making as it is concerned with variation in experience. When applied to the study of new graduate nurses, phenomenography can provide valuable information in relation to individual differences in learning that arise from experience, what factors influence learning and how they affect clinical decision-making ability.

Clinical Competence↗
PubMed1996

Orbital sonography in children.

Orbital sonography with color-flow Doppler imaging is a relatively new technology with significant application in the pediatric patient. This review stresses the primary indications for pediatric ophthalmic ultrasound and also discusses those instances where the use of ultrasound supplements other imaging studies.

Child↗
PubMed1996

Intraoperative vascular endoscopy: early and late results.

In a prospective study, 60 consecutive cases of vascular endoscopy were analyzed to examine the role of angioscopy in infrainguinal vascular procedures. A total of 52 patients had 60 separate vascular endoscopy procedures performed as an adjunct to various vascular procedures; results of intraoperative arteriography were available in 38 of 60 cases. All patients were followed for at least 42 months. The 19 patients who underwent thrombectomy with angioscopy were compared with 19 age-matched control subjects who underwent infrainguinal thrombectomy without angioscopy to evaluate the influence of angioscopy on primary and secondary patency rates. Angioscopy allowed observation of 50 lesions; angiography failed to detect three. These findings altered surgical management in 24 cases (40%). Primary patency rates for the control and experimental thrombectomy groups were 38.8% and 6.5% at 42 months, respectively (p = 0.010 based on log-rank test). Secondary patency rates for the control and experimental groups at 42 months were 63.8% and 49%, respectively (p = 0.521). The limb salvage rate was 89% at 42 months for both groups (p = 0.973). Angioscopy provides the clinician with a direct view while he or she is performing vascular procedures. However, there was no statistical improvement in secondary patency and limb salvage rates. Furthermore, the use of angioscopy during thrombectomy may increase the propensity for subsequent intervention as evidenced by the frequency of changes in surgical management and the lower primary patency rate.

Adolescent↗
PubMed1996

The NMDA antagonist MK-801 blocks the extinction of Pavlovian fear conditioning.

Five groups of rats were given Pavlovian fear conditioning. Four groups were then given extinction training. Prior to extinction these groups received an injection of either the noncompetitive NMDA antagonist MK-801 (0.025, 0.05, or 0.1 mg/kg) or saline. The 5th group received saline but no extinction. During testing, the extinction groups given saline or 0.025 mg/kg of MK-801 showed reduced fear, but the groups that had received the higher doses exhibited as much conditioned fear as the saline group, which had not received extinction. This study showed that MK-801 blocked extinction in a dose-dependent manner. The design of the study ruled out the possibility that the effect was due to state-dependency or to MK-801 interfering with the processing of the conditioned stimulus.

Animals↗
PubMed1996

Abdominal aortic aneurysm screening in elderly males with atherosclerosis: the value of physical exam.

The purpose was 1) To assess the prevalence of abdominal aortic aneurysms (AAA) in elderly males with atherosclerosis and 2) to evaluate the value of physical exam (PE) by a vascular surgeon in detecting AAA. A total of ninety-six males older than 55 years referred to vascular surgery clinic with atherosclerotic disease were screened prospectively with PE by a vascular surgeon, followed by ultrasonography (US). Atherosclerosis was documented by ankle brachial index and duplex US. Patients who had recently undergone a vascular procedure, aortography, laparotomy, abdominal computed tomography, or US were excluded. Mean age was 67 years. Patients were 67 per cent Caucasian, 32 per cent black, and 1 per cent Hispanic. Presenting complaints were related to claudication (83%), carotid disease (19%), both (3%), and subclavian stenosis (1%). Patient characteristics included cigarette smoking (85%), hypertension (67%), cardiac disease (51%), diabetes (45%), stroke (18%), and chronic obstructive pulmonary disease (8%). One (1%) 3.7 cm AAA was detected by US. Sensitivity of PE was 100 per cent and specificity 92 per cent. Twenty-two (23%) patients were too obese for us to feel the aortic pulse. Screening cost was $14,250. The prevalence of AAA in this population is very low. AAA screening should be reserved for patients with a positive PE or who are too obese for the examiner to feel the aortic pulse.

Aged↗