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J Foss

Publications and source records attributed to J Foss.

At least 19 recordsLinked to original sources
PubMed2000

Maxillofacial injuries in the pediatric patient.

Approximately 22 million children are injured in the United States annually. Children are uniquely susceptible to craniofacial trauma because of their greater cranial-mass-to-body ratio. The pediatric population sustains 1% to 14.7% of all facial fractures. The majority of these injuries are encountered by boys (53.7% - 80%) who are involved in motor vehicle accidents (up to 80.2%). The incidence of other systemic injury concomitant to facial trauma is significant (10.4% - 88%). The management of the pediatric patient with maxillofacial injury should take into consideration the differences in anatomy and physiology between children and adults, the presence of concomitant injury, the particular stage in growth and development (anatomic, physiologic, and psychologic), and the specific injuries and anatomic sites that the injuries affect. This comprehensive review, based on the last 25 years of the world's English-speaking surgical literature, presents current thoughts on the anatomic and physiologic differences between adults and children, a synopsis of childhood growth and development, and an overview of state-of-the-art management of the pediatric patient who has sustained maxillofacial injury.

Accidents, Traffic↗
PubMed2000

Comparing methods of clinical measurement: reporting standards for bland and altman analysis.

UNLABELLED: In this era of medical technology assessment and evidence-based medicine, evaluating new methods to measure physiologic variables is facilitated by standardization of reporting results. It has been proposed that assessing repeatability be followed by assessing agreement with an established technique. If the "limits of agreement" (mean bias +/- 2SD) are not clinically important, then one could use two measurements interchangeably. Generalizability to larger populations is facilitated by reporting confidence intervals. We identified 44 studies that compared methods of clinical measurement published during 1996 to 1998 in seven anesthesia journals. Although 42 of 44 (95.4%) used the limits of agreement methodology for analysis, several inadequacies and inconsistencies in reporting the results were noted. Limits of agreement were defined a priori in 7.1%, repeatability was evaluated in 21.4%, and relationship (pattern) between difference and average was evaluated in 7.1%. Only one of the articles reported confidence intervals. A computer macro for the Minitab statistical package (State College, PA) is described to facilitate reporting of Bland and Altman analysis with confidence intervals. We propose standardization of nomenclature in clinical measurement comparison studies. IMPLICATIONS: A literature review of anesthesia journals revealed several inadequacies and inconsistencies in statistical reports of results of comparison studies with regard to interchangeability of measurement methods. We encourage journal editors to evaluate submissions on this subject carefully to ensure that their readers can draw valid conclusions about the value of new technologies.

Anesthesiology↗
PubMed2000

Multistability in recurrent neural loops arising from delay.

The dynamics of a recurrent inhibitory neural loop composed of a periodically spiking Aplysia motoneuron reciprocally connected to a computer are investigated as a function of the time delay, tau, for propagation around the loop. It is shown that for certain choices of tau, multiple qualitatively different neural spike trains co-exist. A mathematical model is constructed for the dynamics of this pulsed-coupled recurrent loop in which all parameters are readily measured experimentally: the phase resetting curve of the neuron for a given simulated postsynaptic current and tau. For choices of the parameters for which multiple spiking patterns co-exist in the experimental paradigm, the model exhibits multistability. Numerical simulations suggest that qualitatively similar results will occur if the motoneuron is replaced by several other types of neurons and that once tau becomes sufficiently long, multistability will be the dominant form of dynamical behavior. These observations suggest that great care must be taken in determining the etiology of qualitative changes in neural spiking patterns, particularly when propagation times around polysynaptic loops are long.

Action Potentials↗
PubMed1999

Reducing myoclonus after etomidate.

BACKGROUND: The authors hypothesized that myoclonus after etomidate is dose-related, could be suppressed when small doses of etomidate were administered before induction, and is unassociated with seizure-like activity on electroencephalogram (EEG). METHODS: Three studies were performed. In the first study, 36 men were randomly assigned to receive 0.025, 0.050, 0.075, 0.100, 0.200, or 0.300 mg/kg of etomidate. In a second crossover study, eight men were randomly allocated to receive either a pretreatment dose of 0.050 mg/kg etomidate or placebo 50 s before 0.300 mg/kg etomidate was injected. EEG was recorded for subjects in the first two studies. In a third study, 60 patients were randomly allocated to one of three pretreatment doses of etomidate: 0.030, 0.050, or 0.075 mg/kg before 0.300 mg/kg was given. RESULTS: In Study 1, myoclonus was not observed after 0.025 or 0.050 mg/kg etomidate. One volunteer had myoclonus after 0.075 mg/kg and another after 0.100 mg/kg etomidate; three had myoclonus after 0.200 mg/kg; and five after 0.300 mg/kg. Incidence of myoclonus was dose-related (P < or = 0.01). In Study 2, two volunteers (25%) with etomidate pretreatment had mild myoclonus compared to six (75%) with placebo pretreatment (P < or = 0.05). EEG changes, other than delta waves, were not seen during myoclonic epochs. In Study 3, myoclonus was less likely after the small pretreatment doses (0.030 or 0.050 mg/kg) than after the large dose (0.075 mg/kg, P < or = 0.01). CONCLUSIONS: Incidence and intensity of myoclonus after induction with etomidate are dose-related, suppressed by pretreatment, and unassociated with seizure-like EEG activity.

Adult↗
PubMed1997

Haemolysis after etomidate: comparison of propylene glycol and lipid formulations.

We sought to determine if the solvent in the formulation of etomidate is responsible for haemolysis in patients. In a randomized, prospective, double-blind study of 49 patients undergoing otolaryngological surgery, patients received etomidate dissolved in propylene glycol or in lipid emulsion. Concentrations of free haemoglobin and haptoglobin were measured before and for up to 360 min after injection of etomidate. Free haemoglobin concentrations increased by 216.8 mg litre-1 in patients who received the propylene glycol formulation and by 11.8 mg litre-1 in the lipid emulsion group (P < or = 0.0004). Correspondingly, reductions in haptoglobin concentrations were significantly greater in the propylene glycol group (P < or = 0.002). We conclude that with respect to haemolysis, lipid emulsion is superior to propylene glycol as a solvent for etomidate.

Anesthetics, Intravenous↗
PubMed1996

Efficient parathyroidectomy guided by SPECT-MIBI and hormonal measurements.

UNLABELLED: Parathyroidectomy is a difficult and lengthy operation which is noncurative in 6% to 10% of cases. To improve the efficiency of this operation, a new dual diagnostic approach was prospectively applied. METHODS: Preoperative tomographic 99mTc-sestamibi (MIBI) scintography and intraoperative measurements of circulating parathyroid hormone (PTH) levels by a quick assay (QPTH) were used. Scintigraphy comprised immediate and delayed planar and SPECT of the neck and chest, following 20 mCi MIBI. The presence and location of persistent foci of abnormal activity found within the neck mediastinum on volume-rendered reprojection (RPJ) of the SPECT data were reported. The surgion, guided by the three-dimensional MIBI-SPECT/RPJ images, identified and excised the single or most prominent scintigraphic focus and applied the QPTH. If PTH levels fell from baseline by at least 50%, the operation was concluded. RESULTS: The operative time of primary parathyroidectomy was reduced from an average of 90 min (before the introduction of scintigraphy and intraoperative PTH measurements) to 57 min. All but two patients became normocalcemic. In 58 consecutive patients with hyperparathyroidism, MIBI-SPECT/RPJ correctly and precisely identified 51 of 53 (96%) primary parathyroid adenomas, 14 to 15 secondary hyperplasias and 2 of 3 hyperplastic glands in MEN (sensitivity 94%, specificity 92%). QPTH verified the excision of the primary parathyroid adenomas and predicted normocalcemia in 50 of 52 patients. In 6 patients with misleading scintigraphy, QPTH was especially useful and guided the surgeon to continue the operation until the abnormal parathyroid tissue was found and excised. CONCLUSION: MIBI-SPEC/RPJ and QPTH sequentially applied improved the efficiency of parathyroidectomy.

Adenoma↗
PubMed1994

Relative effectiveness of four preoperative tests for predicting adverse cardiac outcomes after vascular surgery: a meta-analysis.

Various noninvasive tests have been proposed to stratify perioperative cardiovascular risk, including dipyridamole thallium scintigraphy (DTS), ejection fraction estimation by radionuclide ventriculography (RNV), ischemia monitoring by ambulatory electrocardiography (AECG), and dobutamine stress echocardiography (DSE). Which of these tests is most effective for predicting adverse perioperative cardiac outcome? To answer this question, and also to stimulate future studies, we evaluated 56 studies examining one or more of the four tests. We conducted meta-analysis on 20 studies that met the inclusion criteria. Outcome measures evaluated were cardiac death or myocardial infarction occurring during hospital stay or within 1 mo after surgery. Relative risk (RR), which is the probability of adverse cardiac outcome when the test is positive divided by the probability of adverse outcome when the test is negative, was used to combine evidence from different studies. An empirical Bayes procedure with a normal-normal hierarchic model was then used to obtain a meta-analytic confidence interval for the overall median of the relative risks. The between-study variance was estimated using the method of moments approach described by DerSimonian and Laird (Controlled Clin Trials 1986;7:177-88). Combined (median) RR [95% confidence interval (CI)] and the number of studies included in our meta-analysis for different evaluative tests were as follows: DTS 4.6 (2.1-10.4) (n = 6); RNV 3.7 (1.6-8.3) (n = 5); AECG 2.7 (1.4-5.1) (n = 6), and DSE 6.2 (1.7-22.8) (n = 3). We conclude that while DTS, RNV, AECG, and DSE are effective (the 95% CIs are greater than 1.0) in predicting the cardiac outcome after vascular surgery, the data are not definitive in determining the optimal test (95% CIs for RR overlap). Future studies should include DSE, as this test shows great promise for predicting adverse cardiac events after vascular surgery.

Coronary Angiography↗
PubMed1993

AORN membership survey results.

The 1993 survey is the first step in a planned, systematic method of eliciting members' opinions, demographic information, and program preferences. The data collected will be used to analyze current programs and services and plan for the future. There are limitations to survey research. Questions may be deleted accidentally or worded in such a way that respondents answer them incorrectly. In this survey, there were limitations in the questions pertaining to salary. Respondents were not asked to identify if they were employed full time or part time when they selected salary ranges. Even with these limitations, the respondent population appears to be of sufficient size to ensure a validity in the 95% range.

Adult↗
PubMed1993

A proposal to use confidence intervals for visual analog scale data for pain measurement to determine clinical significance.

Visual analog scales (VAS) ranging from 0 cm (no pain) to 10 cm (worst imaginable pain) are used widely for pain measurement, but various investigators have not treated these data consistently. Conventional statistical tests of such data, although evaluating the "statistical significance" may obscure the clinical value of a treatment. On the other hand, confidence intervals (CIs) can illuminate both statistical and clinical importance. CIs give a range of values based on the observed data which contain, with a specified probability, a true but unknown variable typifying a population. We reviewed 112 articles published recently in anesthesia journals for statistical reporting of VAS data. Of the 112 articles, only two used CIs to report mean pain scores and one used CIs to report differences in median pain scores between the study groups. Only two articles presented 95% CI for the mean pain scores graphically. Analgesic techniques that produce VAS values in the range of 0-3 have been reported to represent adequate analgesia. A graphical method using CIs is proposed that allows ready interpretation of VAS data. With this approach, one evaluates whether the 95% CI for the mean pain score in a group during a particular period lies entirely within the zone defined as "analgesic success" (0-3). Such an analysis allows a visual assessment of whether a particular technique would produce clinically important effects in the population at large. This approach seems to provide more information than the use of conventional hypothesis testing in the interpretation of VAS data for pain measurement.

Confidence Intervals↗
PubMed1992

Assessing work retention issues.

Within 6 months, a 10-member Nursing Services task force created and administered a literature-based retention survey. Tool development and administration is described. The 33-item tool was completed by 85% of the staff. Responses led to the formation of work groups, charged with addressing dissatisfiers and communicating implementation strategies to the hospital at large.

Adult↗
PubMed1982

A Golgi analysis of cerebellar immunopathy in neonatal rats after infection with lymphocytic choriomeningitis virus.

Morphological changes in cerebellar neurons during the immune reaction to a viral infection were examined using Golgi methods. Wistar albino rats, infected at 4 days of age with lymphocytic choriomeningitis virus, were killed on postinfection days 4 to 10, and the cerebella were processed by rapid Golgi and Golgi-Cox methods. Some of the sections impregnated by the rapid Golgi method were subsequently processed for electron microscopy. Necrosis was evident in the lingula and portions of the posterior vermis by postinjection day 7. By the 9th day, degeneration was observed throughout the vermis. Purkinje cells appeared normal 4 days after infection, but by days 9 and 10, all the impregnated Purkinje cells had atrophic cell bodies; stunted, agglomerate dendrites; and dilated axons with collaterals that had many short processes. Some cells in the infected tissue did not resemble any normal cell type. These data indicate that the value of the Golgi method is a useful complement to conventional techniques for examining the neuropathological response to viral infections. In fact, it provides neuropathological information that is difficult or impossible to obtain with other procedures.

Animals↗
PubMed1980

Tinidazole and doxycycline as antimicrobials in elective colorectal surgery. A randomized multicentre trial.

A prospective randomized study on the effect of doxycycline alone, tinidazole alone and the two antimicrobials in two different combinations as prophylactic antimicrobials on elective colorectal surgery is presented (Table II). The number of patients included in the study was 265. Of the four different treatment groups, the one which consisted of a single preoperative dose of tinidazole 2 g and doxycycline 200 mg, seemed to give the most favourable result. In this treatment group (n = 70), wound sepsis was recorded in 7.2% and perineal sepsis in 34.8% of the cases. Only one serious, but non-fatal intra-abdominal complication (1.4%) was observed in this group. The trial did not include a placebo group.

Aged↗