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M Mitchell

Publications and source records attributed to M Mitchell.

275 records · Page 16Linked to original sources

Management of dizziness in primary care.

BACKGROUND: We sought to determine the types of dizziness problems that are commonly seen in primary care practices, and to bring to light clinical and demographic factors that predict management decisions. METHODS: We undertook a prospective cohort study with a 6-month follow-up using data gathered in nine primary care practices in two North Carolina counties. Subjects were 144 dizziness patients examined by primary care physicians. Data collected included demographic characteristics, a standardized dizziness history, physician estimation of symptom severity and diagnostic certainty, and physician "worry" about arrhythmia, transient ischemic attack, and brain tumor. Physicians reported their management decisions and diagnosis (or differential diagnosis) by responding to a questionnaire after completing the patient encounter. A 6-month follow-up chart review and physician interview were completed on 140 patients (97.2 percent); information obtained included changes in diagnosis and patient mortality. RESULTS: The most common diagnoses were labyrinthitis, otitis media, benign positional vertigo, unspecified presyncope, sinusitis, and transient ischemic attack. The initial diagnosis changed during the 6-month follow-up period in 34 (24.3 percent) of patients. The overall course of these patients was benign, however, with only one death occurring during the 6-month follow-up period. Patients' dizziness tended to be managed using a combination of strategies, including office laboratory testing (33.6 percent), advanced testing (11.4 percent), referral to a specialist (9.3 percent), medication (61.3 percent), observation (71.8 percent), reassurance (41.6 percent), and behavioral recommendations (15.0 percent). Office laboratory testing was associated with younger patient age, a suspected metabolic or endocrine disorder, and physician worry about a cardiac arrhythmia; advanced laboratory testing was associated with suspected cardiovascular or neurologic disorders. Medication tended to be prescribed for vertigo and severe symptoms and avoided when physicians were worried about a cardiac arrhythmia. Referral to a specialist was associated with suspected neurologic disease. Observation, behavior change, and reassurance were avoided in patients with poorly defined dizziness and tended to be used in older patients. The management approaches employed by the 4 physicians who referred the most subjects to the study varied considerably. CONCLUSIONS: Dizziness in primary care represents an extremely broad spectrum of diagnoses. The generally conservative management approach of primary care physicians in this study is consistent with basic clinical and epidemiologic principles, and patient mortality with this approach is low.

Adolescent↗

Comparative flow rates of saline in commonly used spinal needles including pencil-tip needles.

BACKGROUND AND OBJECTIVES: Certain characteristics of spinal needles that can influence their clinical usefulness were examined, namely, flow rates, internal diameters, and size of orifices of pencil-type needles. METHODS: Flow rates of 0.9% sodium chloride solution were measured in spinal needles with an infusion pressure of 10 mmHg at isothermic and steady-state conditions. In 15 different types, a new needle was used for each experiment, and 6 experiments were performed with each needle type for a total of 90 experiments. The Hagen-Poisseuille Law for laminar flow was used to calculate the internal diameters. RESULTS: The flow rates of needles of the same gauge varied considerably depending on the manufacturer. Compared with 26-gauge ultrathin-wall spinal needle produced by the same manufacturer (Braun, Bethlehem, Pennsylvania), the flow rate through 29-gauge spinal needle was 18% that of the former needle. The flow rate through 27-gauge Quincke Whitacre needle (Becton Dickinson, Rutherford, New Jersey) was not statistically different from that through 26-gauge needle by the same manufacturer. By arbitrarily choosing < or = 2 seconds to be the in vitro desirable period for saline to traverse the needle from one end to the other, all needles with the exception of 29-gauge and standard 26-gauge Quincke Braun needles met this criterion. The length and size of the orifices of Whitacre needles were found to be significantly smaller than those of Sprotte needles (Havel, Cincinnati, Ohio). The orifice of Sprotte needle was longer than the known thickness of the dura while that of the Whitacre needle was smaller. CONCLUSIONS: Needles of the same gauge do not necessarily have the same flow rate. Flow rate correlates well with internal, not external, diameter. By considering < or = 2 seconds to be the desirable time for saline to traverse a spinal needle, all, except two, meet this criterion. The orifice of Whitacre needle has more desirable features than that of Sprottle needle. Anesthesiologists are encouraged to use 27-gauge needles since their flow rate is not slower than that of 26-gauge needles.

Needles↗

Magnetic resonance imaging of the foot and ankle: an updated pictorial review.

The authors describe magnetic resonance imaging (MRI) of the foot and ankle using a variety of cases studied. This modality represents considerable benefit in dealing with the difficult pathologic conditions, as well as clarifying others that may not be evident on plain radiographs. The soft tissue versus osseous abnormalities may be differentiated on the T1 versus T2 images. An excellent pictorial review dealing with the foot and ankle is offered.

Ankle↗

Sturge-Weber syndrome: cranial MR imaging with Gd-DTPA.

PURPOSE: To study the role of Gd-DTPA in cranial MR of patients with Sturge-Weber syndrome. METHODS AND MATERIALS: Seven patients with Sturge-Weber syndrome, ages 3 months to 36 years, were evaluated with unenhanced and contrast-enhanced (Gd-DTPA) MR imaging. Correlation was made to cranial CT in five patients. RESULTS: MR findings included (in decreasing frequency): pial angiomatosis, cerebral atrophy, decrease in cortical veins, enlargement of deep veins, enlargement of choroid plexus, and parenchymal calcification. Contrast MR imaging was essential in diagnosis in four cases in which cranial CT, unenhanced MR, or angiography was normal or demonstrated nonspecific abnormalities. Pial angiomatosis with adjacent cerebral atrophy were the only consistent radiographic abnormalities. CONCLUSION: In all patients, contrast MR demonstrated the radiographic spectrum of central nervous system abnormalities in Sturge-Weber syndrome to a greater degree than unenhanced MR or CT and may represent the method of diagnosis in these patients. Demonstration of the pial angioma on contrast MR should be considered the most important criterion for the radiographic diagnosis of Sturge-Weber syndrome.

Adolescent↗

Shared governance as a way to involve staff in decision-making.

Increasing the involvement of clinicians in decision-making is a key part of recent NHS policy. One model designed to increase involvement is shared governance. This article describes the approach to shared governance developed at Kettering General Hospital. Ongoing evaluation of the scheme suggests benefits in terms of personal and professional development for those involved.

Communication↗