Subtherapeutic voriconazole concentrations associated with concomitant dexamethasone: case report and review of the literature

WHAT IS KNOWN AND OBJECTIVE

Voriconazole has significant drug interactions due to metabolism by CYP enzymes. Subtherapeutic voriconazole concentrations associated with concomitant dexamethasone are not well described.

CASE DESCRIPTION

An 84-year-old male was started on voriconazole for a fungal brain abscess. He was readmitted due to clinical failure thought to be the result of subtherapeutic voriconazole concentrations. Dexamethasone was identified as a potential cause due to its induction of CYP enzymes. This interaction was substantiated by sequential troughs that demonstrated a rise in voriconazole concentrations as dexamethasone was tapered off.

WHAT IS NEW AND CONCLUSION

Therapeutic drug monitoring for patients on voriconazole and dexamethasone is essential to prevent suboptimal clinical outcomes.

Inhibition of a novel fibrogenic factor Tl1a reverses established colonic fibrosis

Intestinal fibrostenosis is among the hallmarks of severe Crohn's disease. Patients with certain TNFSF15 (gene name for TL1A) variants over-express TL1A and have a higher risk of developing strictures in the small intestine. In addition, sustained Tl1a expression in mice leads to small and large intestinal fibrostenosis under colitogenic conditions. The aim of this study was to determine whether established murine colonic fibrosis could be reversed with Tl1a antibody (Ab). Treatment with neutralizing Tl1a Ab reversed colonic fibrosis back to the original pre-inflamed levels, potentially as a result of lowered expression of connective tissue growth factor, Il31Ra, transforming growth factor β1 and insulin-like growth factor-1. In addition, blocking Tl1a function by either neutralizing Tl1a Ab or deletion of death domain receptor 3 (Dr3) reduced the number of fibroblasts and myofibroblasts, the primary cell types that mediate tissue fibrosis. Primary intestinal myofibroblasts expressed Dr3 and functionally responded to direct Tl1a signaling by increasing collagen and Il31Ra expression. These data demonstrated a direct role for TL1A-DR3 signaling in tissue fibrosis and that modulation of TL1A-DR3 signaling could inhibit gut fibrosis.

Immunopathology of inflammatory bowel disease

Inflammatory bowel disease (IBD) results from a complex series of interactions between susceptibility genes, the environment, and the immune system. The host microbiome, as well as viruses and fungi, play important roles in the development of IBD either by causing inflammation directly or indirectly through an altered immune system. New technologies have allowed researchers to be able to quantify the various components of the microbiome, which will allow for future developments in the etiology of IBD. Various components of the mucosal immune system are implicated in the pathogenesis of IBD and include intestinal epithelial cells, innate lymphoid cells, cells of the innate (macrophages/monocytes, neutrophils, and dendritic cells) and adaptive (T-cells and B-cells) immune system, and their secreted mediators (cytokines and chemokines). Either a mucosal susceptibility or defect in sampling of gut luminal antigen, possibly through the process of autophagy, leads to activation of innate immune response that may be mediated by enhanced toll-like receptor activity. The antigen presenting cells then mediate the differentiation of naïve T-cells into effector T helper (Th) cells, including Th1, Th2, and Th17, which alter gut homeostasis and lead to IBD. In this review, the effects of these components in the immunopathogenesis of IBD will be discussed.

Leukocyte compartments in the mouse lung: distinguishing between marginated, interstitial, and alveolar cells in response to injury

We developed a flow cytometry-based assay to simultaneously quantify multiple leukocyte populations in the marginated vascular, interstitial, and alveolar compartments of the mouse lung. An intravenous injection of a fluorescently labeled anti-CD45 antibody was used to label circulating and marginated vascular leukocytes. Following vascular flushing to remove non-adherent cells and collection of broncho-alveolar lavage (BAL) fluid, lungs were digested and a second fluorescent anti-CD45 antibody was added ex vivo to identify cells not located in the vascular space. In the naïve mouse lung, we found about 11 million CD45+ leukocytes, of which 87% (9.5 million) were in the vascular marginated compartment, consisting of 17% NK cells, 17% neutrophils, 57% mononuclear myeloid cells (monocytes, macrophage precursors and dendritic cells), and 10% T cells (CD4+, CD8+, and invariant NKT cells). Non-vascular compartments including the interstitial compartment contained 7.7×10(5)cells, consisting of 49% NK cells, 25% dendritic cells, and 16% other mononuclear myeloid cells. The alveolar compartment was overwhelmingly populated by macrophages (5.63×10(5)cells, or 93%). We next studied leukocyte margination and extravasation into the lung following acid injury, a model of gastric aspiration. At 1 h after injury, neutrophils were markedly elevated in the blood while all other circulating leukocytes declined by an average of 79%. At 4 h after injury, there was a peak in the numbers of marginated neutrophils, NK cells, CD4+ and CD8+ T cells and a peak in the number of alveolar NK cells. Most interstitial cells consisted of DCs, neutrophils, and CD4+ T cells, and most alveolar compartment cells consisted of macrophages, neutrophils, and NK cells. At 24 h after injury, there was a decline in the number of all marginated and interstitial leukocytes and a peak in alveolar neutrophils. In sum, we have developed a novel assay to study leukocyte margination and trafficking following pulmonary inflammation and show that marginated cells comprise a large fraction of lung leukocytes that increases shortly after lung injury. This assay may be of interest in future studies to determine if leukocytes become activated upon adherence to the endothelium, and have properties that distinguish them from interstitial and circulating cells.

Interleukin-10/Ceftriaxone prevents E. coli-induced delays in sensorimotor task learning and spatial memory in neonatal and adult Sprague-Dawley rats

Intrauterine infection during pregnancy is associated with early activation of the fetal immune system and poor neurodevelopmental outcomes. Immune activation can lead to alterations in sensorimotor skills, changes in learning and memory and neural plasticity. Both interleukin-10 (IL-10) and Ceftriaxone have been shown to decrease immune system activation and increase memory capacity, respectively. Using a rodent model of intrauterine infection, we examined sensorimotor development in pups, learning and memory, via the Morris water maze, and long-term potentiation in adult rats. Pregnant rats at gestational day 17 were inoculated with 1 x 10(5) colony forming units of Escherichia coli (E. coli) or saline. Animals in the treatment group received IL-10/Ceftriaxone for 3 days following E. coli administration. Intrauterine infection delayed surface righting, negative geotaxis, startle response and eye opening. Treatment with IL-10/Ceftriaxone reduced the delay in these tests. Intrauterine infection impaired performance in the probe trial in the Morris water maze (saline 25.13+/-1.01; E. coli 20.75+/-1.01; E. coli+IL-10/Ceftriaxone 20.2+/-1.62) and reduced the induction of long-term potentiation (saline 141.5+/-4.3; E. coli 128.7+/-3.9; E. coli+IL-10/Ceftriaxone 140.0+/-10). In summary, the results of this study indicate that E. coli induced intrauterine infection delays sensorimotor and learning and memory, while IL-10/Ceftriaxone rescues some of these behaviors. These delays were also accompanied by an increase in interleukin-1beta levels, which indicates immune activation. IL-10/Ceftriaxone prevents these delays as well as decreases E. coli-induced interleukin-1beta activation and may offer a window of time in which suitable treatment could be administered.

Adenosine A2A receptor activation reduces infarct size in the isolated, perfused mouse heart by inhibiting resident cardiac mast cell degranulation

Mast cells are found in the heart and contribute to reperfusion injury following myocardial ischemia. Since the activation of A2A adenosine receptors (A2AARs) inhibits reperfusion injury, we hypothesized that ATL146e (a selective A2AAR agonist) might protect hearts in part by reducing cardiac mast cell degranulation. Hearts were isolated from five groups of congenic mice: A2AAR+/+ mice, A2AAR(-/-) mice, mast cell-deficient (Kit(W-sh/W-sh)) mice, and chimeric mice prepared by transplanting bone marrow from A2AAR(-/-) or A2AAR+/+ mice to radiation-ablated A2AAR+/+ mice. Six weeks after bone marrow transplantation, cardiac mast cells were repopulated with >90% donor cells. In isolated, perfused hearts subjected to ischemia-reperfusion injury, ATL146e or CGS-21680 (100 nmol/l) decreased infarct size (IS; percent area at risk) from 38 +/- 2% to 24 +/- 2% and 22 +/- 2% in ATL146e- and CGS-21680-treated hearts, respectively (P < 0.05) and significantly reduced mast cell degranulation, measured as tryptase release into reperfusion buffer. These changes were absent in A2AAR(-/-) hearts and in hearts from chimeric mice with A2AAR(-/-) bone marrow. Vehicle-treated Kit(W-sh/W-sh) mice had lower IS (11 +/- 3%) than WT mice, and ATL146e had no significant protective effect (16 +/- 3%). These data suggest that in ex vivo, buffer-perfused hearts, mast cell degranulation contributes to ischemia-reperfusion injury. In addition, our data suggest that A2AAR activation is cardioprotective in the isolated heart, at least in part by attenuating resident mast cell degranulation.

Oropharyngeal Scintigraphy: A Reliable Technique for the Quantitative Evaluation of Oral–Pharyngeal Swallowing

A valid and reliable technique to quantify the efficiency of the oral-pharyngeal phase of swallowing is needed to measure objectively the severity of dysphagia and longitudinal changes in swallowing in response to intervention. The objective of this study was to develop and validate a scintigraphic technique to quantify the efficiency of bolus clearance during the oral-pharyngeal swallow and assess its diagnostic accuracy. To accomplish this, postswallow oral and pharyngeal counts of residual for technetium-labeled 5- and 10-ml water boluses and regional transit times were measured in 3 separate healthy control groups and in a group of patients with proven oral-pharyngeal dysphagia. Repeat measures were obtained in one group of aged (> 55yr) controls to establish test-retest reliability. Scintigraphic transit measures were validated by comparison with radiographic temporal measures. Scintigraphic measures in those with proven dysphagia were compared with radiographic classification of oral vs. pharyngeal dysfunction to establish their diagnostic accuracy. We found that oral ( p = 0.04), but not pharyngeal, isotope clearance is swallowed bolus-dependently. Scintigraphic transit times do not differ from times derived radiographically. All scintigraphic measures have extremely good test-retest reliability. The mean difference between test and retest for oral residual was -1% (95% CI -3%-1%) and for pharyngeal residual it was -2% (95% CI -5%-1%). Scintigraphic transit times have very poor diagnostic accuracy for regional dysfunction. Abnormal oral and pharyngeal residuals have positive predictive values of 100% and 92%, respectively, for regional dysfunction. We conclude that oral-pharyngeal scintigraphic clearance is highly reliable, bolus volume-dependent, and has a high predictive value for regional dysfunction. It may prove useful in assessment of dysphagia severity and longitudinal change.

Reduced placental perfusion causes an increase in maternal serum leptin

OBJECTIVE

We tested the hypothesis that the inadequately perfused placenta increases production of leptin, which can be detected in maternal serum.

STUDY DESIGN

Sprague-Dawley rats (n=13), on day 14 of gestation, had placement of clips on the aorta and the ovarian arteries providing 35 per cent occlusion of the vessels. Eight rats had sham surgery and 14 rats served as non-surgical controls. All animals were sacrificed on day 19 of gestation. Maternal serum was obtained, and pups and placentae were weighed.

RESULTS

Both placental weights and pup weights were reduced due to reduced uterine perfusion and were negatively correlated with maternal serum leptin (P=0.018 and 0.028, respectively). Maternal serum leptin was increased in the treatment group (2.21 ng/ml+/-64 ng/ml) compared to controls (1.66 ng/ml+/-38 ng/ml) (P=0.031).

CONCLUSIONS

Our findings suggest that reduced placental perfusion results in an increase in maternal serum leptin. Further investigation is needed to determine if maternal serum leptin may be useful in identifying pregnancies with uteroplacental insufficiency.

Intravenous pyridoxine-induced metabolic acidosis

STUDY OBJECTIVE

Pyridoxine hydrochloride, the antidote for isonicotinic acid hydrazide (INH)--induced seizures, is available in solution at a concentration of 100 mg/mL at a pH of less than 3. Pyridoxine is often infused rapidly in large doses for INH-induced seizures. Effects of pyridoxine infusion on base deficit in amounts given for INH poisoning have not been studied in human subjects. We hypothesized that this infusion would result in transient worsening of acidosis.

METHODS

We conducted a randomized, controlled crossover trial in human volunteers. Five healthy volunteers (mean age, 35 years; range, 29 to 43 years) were randomized to receive intravenous placebo (50 mL of normal saline solution) or 5 g of pyridoxine (50 mL) over 5 minutes. A peripheral intravenous catheter was established in each arm, and a heparinized venous blood sample was obtained for base deficit at baseline and 3, 6, 10, 20, and 30 minutes after infusion. After at least a 1-week washout period, the volunteers were assigned to the alternate arms of the experiments, thus acting as their own control subjects. Data were analyzed by using the 2-tailed paired t test, controlling for multiple comparisons.

RESULTS

No difference was noted between groups at baseline. A statistically significant increased base deficit was noted after the pyridoxine infusion versus control at 3 to 20 minutes but not at 30 minutes (P =.1). Maximal mean increase in base deficit (2.74 mEq/L) was noted at 3 minutes.

CONCLUSION

A transient increase in base deficit occurs after the infusion of 5 g of pyridoxine in normal volunteers.

Diagnostic use of physicians' detection of urine fluorescence in a simulated ingestion of sodium fluorescein-containing antifreeze

STUDY OBJECTIVE

We sought to assess physicians' ability to accurately determine the presence or absence of sodium fluorescein (SF) in urine at a concentration corresponding to that present after ingestion of a toxic amount of commercial automotive antifreeze.

METHODS

We studied 2 different urine specimen evaluation formats--one presenting isolated specimens, and the other presenting specimens grouped for comparison--to determine whether the visual clues afforded by grouped comparison aided the accuracy of the evaluation. On each study day, 3 urine specimens (1 control specimen obtained before SF administration and 2 specimens obtained after SF administration) were obtained from each of 9 or 10 volunteers. Each of these 27 or 30 urine specimens were presented sequentially and in random order to 2 emergency physicians during separate evaluation time periods. Each physician was asked to classify each specimen as fluorescent or nonfluorescent (sequential format). After a rest period, each physician, again separately, was asked to look at the same 27 or 30 urine specimens, this time all together in a test tube rack so that grouped comparisons were possible. The physicians again classified each sample as either fluorescent or nonfluorescent (grouped format). We assessed sensitivity, specificity, and accuracy of the evaluation by each presentation format (sequential or grouped).

RESULTS

Mean examiner sensitivity, specificity, and accuracy for detecting the presence of SF in urine using the sequential presentation format were 35%, 75%, and 48%, respectively, whereas the same test performance indices were 42%, 66%, and 50%, respectively, when the grouped format was used.

CONCLUSION

Wood's lamp determination of urine fluorescence is of limited diagnostic utility in the detection of SF ingestion in an amount equivalent to toxic ingestion of some ethylene glycol--containing automotive antifreeze products.

Development and validation of a self-report symptom inventory to assess the severity of oral-pharyngeal dysphagia

BACKGROUND & AIMS

The aim of this study was to develop and evaluate the validity and reliability of a self-report inventory to measure symptomatic severity of oral-pharyngeal dysphagia.

METHODS

Test-retest reliability and face, content, and construct validity of a prototype visual analogue scale inventory were assessed in 45 patients who had stable, neuromyogenic dysphagia.

RESULTS

Normalized scores varied over time by -0.5% +/- 17.6% (95% confidence interval, -9.2% to 8.2%). Factor analysis identified a single factor (dysphagia), to which 18 of 19 questions contributed significantly, that accounted for 56% of total variance (P < 0.0001). After deletion of 2 questions with poor face validity and patient compliance, this proportion increased to 59%; mean test-retest change was -2% (95% confidence interval, -11% to 7%); and total score correlated highly with an independent global assessment severity score (r = 0.7; P < 0.0001). A mean 70% reduction in score (P < 0.0001) was observed after surgery in patients with Zenker's diverticulum (discriminant validity).

CONCLUSIONS

Applied to patients with neuromyogenic dysphagia, the 17-question inventory shows strong test-retest reliability over 2 weeks as well as face, content, and construct validity. Discriminant validity (responsiveness) has been demonstrated in a population with a correctable, structural cricopharyngeal disorder. Responsiveness of the instrument to treatment in neuromyogenic dysphagia remains to be quantified.

Cricopharyngeal myotomy does not increase the risk of esophagopharyngeal acid regurgitation

OBJECTIVE

It is not known whether cricopharyngeal myotomy predisposes to esophagopharyngeal regurgitation. Using ambulatory, dual pharyngeal, and esophageal pH monitoring before and after cricopharyngeal myotomy, our aim was to determine the effect, if any, of myotomy on the frequency of esophagopharyngeal acid regurgitation.

METHODS

We studied prospectively 18 patients who underwent cricopharyngeal myotomy for pharyngeal dysphagia (10 Zenker's, eight neurogenic dysphagia), of whom 17 agreed to undergo dual pH monitoring preoperatively, and 10 who agreed to both pre- and postoperative monitoring.

RESULTS

Symptoms of gastroesophageal reflux disease were present in 30%. Cricopharyngeal myotomy significantly reduced basal upper esophageal sphincter pressure by 49%, from 37+/-5 mm Hg to 19+/-3 mm Hg (p = 0.007). Esophagopharyngeal regurgitation was a rare event and the frequency of it did not differ between patients and healthy controls. Preoperatively, three regurgitation events in two patients did not differ from the postoperative frequency of a total of two events in the same two patients.

CONCLUSIONS

Increased esophageal acid exposure is common and esophagopharyngeal regurgitation is rare in unselected patients undergoing cricopharyngeal myotomy for pharyngeal dysphagia. Myotomy does not increase the frequency of esophagopharyngeal acid regurgitation in such patients.

Esophagopharyngeal acid regurgitation: dual pH monitoring criteria for its detection and insights into mechanisms

BACKGROUND & AIMS

A valid technique for the detection of esophagopharyngeal acid regurgitation would be valuable to evaluate suspected reflux-related otolaryngologic and respiratory disorders. The aim of this study was to derive pH criteria that optimally define esophagopharyngeal acid regurgitation and to examine patterns of regurgitation.

METHODS

In 19 healthy controls and 15 patients with suspected regurgitation, dual or quadruple pH sensors were used to monitor pharyngeal and esophageal pH. For each combination of the 2 variables, DeltapH and nadir pH, proportions of pH decreases that occurred during or independent of esophageal acidification were calculated to determine the likelihood that an individual pharyngeal pH decrease was a candidate regurgitation event or a definite artifact.

RESULTS

Overall, 92% of pharyngeal pH decreases of 1-2 pH units and 66% of pH decreases of this magnitude reaching a nadir pH of <4 were artifactual. Optimal criteria defining a pharyngeal acid regurgitation event were a pH decrease that occurred during esophageal acidification, had a DeltapH of >2 units, and reached a nadir of <4 units in less than 30 seconds. Regurgitation occurred more frequently in subjects in an upright (32 of 35) than in a supine (3 of 35 events; P </= 0.0001) position and was more frequently abrupt (synchronous with esophageal acidification) than delayed (P </= 0.05).

CONCLUSIONS

Accepted criteria for gastroesophageal reflux are not applicable to the detection of esophagopharyngeal acid regurgitation, and most regurgitation occurs abruptly and in upright position.

Self-inflicted burn injuries: an 11-year retrospective study

The burns unit at the Royal Brisbane Hospital accepted a total of 2275 admissions from 1986 to 1996. During this 11-year period, 65 cases of self-inflicted burn injury were treated, which made up 2.9% of the total number of admissions. A mortality rate of 21.5% (14 patients) is noted, with all patients dying after admission to the hospital. A common feature of people that self-inflict burn injuries is a psychiatric history, with many patients having histories of self-harm or suicide attempts. Two distinct groups were identified--those with suicidal intent and those with intent of self-harm. Those patients with self-inflicted injuries have an increased mean of 31.4% total body surface area burned as compared with those patients whose injuries are accounted for as accidental, which have a mean total body surface area burned of 10%. Additionally, the mean length of stay in the hospital for patients with self-inflicted injuries was 40 days for acute injuries, which is prolonged; the mean length of stay for acute injuries that were not self-inflicted was 14 days. This investigation discovered 3 cases of repeated self-inflicted burn injury.

Acute cyanide toxicity caused by apricot kernel ingestion

A 41-year-old woman ingested apricot kernels purchased at a health food store and became weak and dyspneic within 20 minutes. The patient was comatose and hypothermic on presentation but responded promptly to antidotal therapy for cyanide poisoning. She was later treated with a continuous thiosulfate infusion for persistent metabolic acidosis. This is the first reported case of cyanide toxicity from apricot kernel ingestion in the United States since 1979.

Effect of magnesium hydroxide on iron absorption following simulated mild iron overdose in human subjects

OBJECTIVE

To determine the effect of oral magnesium hydroxide [Mg(OH)2] on iron absorption after simulated iron overdose in human subjects.

METHODS

A randomized, controlled crossover study was conducted in healthy adult male human volunteers taking no medications. Subjects received an average of 5.0 mg/kg elemental iron orally followed 1 hour later by either oral administration of 4.5 g of Mg(OH)2 per g ingested elemental iron or no treatment. Serial serum specimens were obtained over the 12 hours following iron ingestion and stored at -60 degrees C until standard serum iron assay was performed. After a 2-week washout period, the subjects were enrolled in the alternative trial arm. Individual baseline diurnal variation in serum iron levels was determined over a 12-hour period on the day prior to each trial. Area under time-concentration curves (AUCs) were calculated, and the AUC due to experimental iron ingestion (deltaAUC) was determined by subtracting the baseline diurnal AUC from the experimental AUC for each subject.

RESULTS

Thirteen healthy adult male subjects were enrolled. Mean +/- SEM for deltaAUC due to experimental iron ingestion followed by treatment with Mg(OH)2, 78 +/- 23 micromol(hr)/L, was significantly less than that followed by no treatment, 144 +/- 33 micromol(hr)/L (p = 0.03 by signed rank test).

CONCLUSIONS

Magnesium hydroxide, administered 1 hour post-iron ingestion at an oral dose of 4.5 g per g elemental iron ingested, significantly reduced iron absorption during a 12-hour period following simulated mild iron overdose in healthy adult human volunteers.

Influence of altered tongue contour and position on deglutitive pharyngeal and UES function

The potential influence of altered lingual position and contour during the bolus loading phase of the swallow in mediating the swallowed bolus volume-dependent regulation of upper esophageal sphincter (UES) relaxation and opening was studied in 15 healthy volunteers using simultaneous videoradiography and manometry. A maxillary dental splint modulated tongue deformity during the early oral phase of deglutition. We examined the effect of the splint and swallowed bolus density on bolus volume-dependent changes in the timing of events in the swallow sequence and on hypopharyngeal intrabolus and midpharyngeal pressures. Peak mid-pharyngeal pressure (P = 0.001) and hypopharyngeal intrabolus pressure (P = 0.04) were significantly reduced by the splint. The normal volume-dependent earlier onset of sphincter relaxation and opening was preserved with the splint in situ. The splint significantly delayed the onset of hyoid motion and UES relaxation and opening without influencing transit times or total swallow duration. Alterations in tongue contour and position reduce intrabolus pressure and pharyngeal contraction without influencing normal bolus volume-dependent regulation of timing of UES relaxation and opening.

Antibiotic-induced convulsions

Convulsive episodes are associated with the use of a number of antimicrobial agents. Although seizures may be a feature of the disease being treated, antibiotics should be considered possible causes of seizures, particularly if suggested by temporal relationships between seizure activity and drug administration. The astute clinician should be aware of the clinical settings in which antibiotic-induced seizures occur, be familiar with likely agents and their mechanisms of toxicity, and be prepared to institute appropriate management directed at this adverse effect of antimicrobial therapy.

Predictors of outcome following cricopharyngeal disruption for pharyngeal dysphagia

The indications for, and predictors of outcome following cricopharyngeal disruption in pharyngeal dysphagia are not clearly defined. Our purpose was to examine the symptomatic response to cricopharyngeal disruption, by either myotomy or dilatation, in patients with oral-pharyngeal dysphagia and to determine pre-treatment manometric or radiographic predictors of outcome. Using simultaneous pharyngeal videoradiography and manometry, we studied 20 patients with pharyngeal dysphagia prior to cricopharyngeal dilatation (n = 11) or myotomy (n = 8), and 23 healthy controls. We measured peak pharyngeal pressure, hypopharyngeal intrabolus pressure, upper esophageal sphincter diameter, and coordination. Response rate to sphincter disruption was 65%. The extent of sphincter opening was significantly reduced in patients compared with controls (p = 0.004), but impaired sphincter opening was not a predictor of outcome. Increased hypopharyngeal intrabolus pressures (> 19 mmHg for 10 ml bolus; > 31 mmHg for 20 ml bolus) was a significant predictor of outcome (p = 0.01). Neither peak pharyngeal pressure nor incoordination were predictors of outcome. In pharyngeal dysphagia, hypopharyngeal intrabolus pressure, and not peak pharyngeal pressure, is a predictor of response to cricopharyngeal disruption. The relationship between intrabolus pressure and impaired sphincter opening is an indirect measure of sphincter compliance which helps predict therapeutic response.

Mechanisms of oral-pharyngeal dysphagia in patients with Parkinson's disease

BACKGROUND & AIMS

Oral-pharyngeal dysphagia in Parkinson's disease is well recognized. The aim of this study was to establish the mechanisms of oral-pharyngeal dysphagia in these patients.

METHODS

Using simultaneous videoradiography and pharyngeal manometry, we studied 19 patients with Parkinson's disease (12 with oral-pharyngeal dysphagia and 7 without oral-pharyngeal dysphagia) and compared them with 23 healthy controls.

RESULTS

the clinical severity of Parkinson's disease predicted neither the presence nor the severity of dysphagia. Minor alterations in oral function were common in controls and patients, but pharyngeal dysfunction was significantly more prevalent in patients. Incomplete upper esophageal sphincter (UES) relaxation was present in 4 patients (21%), all of whom showed increased hypopharyngeal intrabolus pressure, but not all of whom had a diminished UES opening. The patients had a reduced UES diameter (P = 0.004) and a higher intrabolus pressure compared with the controls (P = 0.007). Pharyngeal contraction pressures were lower in patients, but 6 patients with dysphagia and an abnormal pharyngeal wall motion had normal peak pressures.

CONCLUSIONS

An incomplete UES relaxation and a reduced UES opening, both associated with high intrabolus pressure, are prevalent in Parkinson's disease. Oral-pharyngeal dysphagia in Parkinson's disease is multifactorial, with the majority of patients showing oral and pharyngeal dysfunction, even before the clinical expression of dysphagia. Impaired pharyngeal bolus transport is the major determinant of dysphagia.

Influence of cold stimulation on the normal pharyngeal swallow response

We examined the potential influence of cold stimulation of the anterior tonsillar pillars, before and after topical anesthesia, on the temporal linkage between the oral and pharyngeal components of the swallow. We hypothesized that if elicitation of the pharyngeal swallow were dependent upon stimulation of faucial mucosal receptors this response would be facilitated by cold tactile stimulation and inhibited by topical anesthesia. In 14 healthy volunteers undergoing simultaneous videoradiography and manometry we measured and compared regional transit and clearance times, and the timing of hyoid motion, upper esophageal sphincter relaxation, and opening within the swallow sequence. There was a significant, volume-dependent forward shift in timings of hyoid motion, upper esophageal sphincter (UES) relaxation profile, and opening which were influenced neither by cold stimulation nor topical anesthesia. Regional transit and clearance times and UES coordination were not influenced by cold stimulation. Pharyngeal clearance time was prolonged by tonsillar pillar anesthesia due to earlier arrival of the bolus head at this region (p = 0.002). We conclude that the normal pharyngeal swallow response is neither facilitated nor inhibited by prior cold tactile stimulation or topical anesthesia to the tonsillar pillars, respectively. These observations do not support the hypothesis that elicitation of the pharyngeal swallow response is dependent upon stimulation of mucosal receptors in the tonsillar arches.

Influence of mucosal receptors on deglutitive regulation of pharyngeal and upper esophageal sphincter function

The potential influence of mucosal sensory receptors on the regulation of oral-pharyngeal swallow events was studied in 15 healthy volunteers using simultaneous videoradiography and manometry. We determined the effects of selective pharyngeal and oral plus pharyngeal anesthesia on the following temporal and manometric measures in response to liquid and viscous swallows: regional transit and clearance times; motion of hyoid and larynx; upper esophageal sphincter relaxation, opening, and closure; and pharyngeal contraction wave characteristics. Under the influence of mucosal anesthesia no subjects demonstrated aspiration during deglutition. Neither regional transit and clearance times nor pharyngosphincteric coordination was influenced significantly by pharyngeal mucosal anesthesia or oral plus pharyngeal anesthesia. Although midpharyngeal and distal pharyngeal contraction amplitudes were not influenced by mucosal anesthesia, midpharyngeal contraction wave duration was reduced significantly by both pharyngeal (P = 0.02) and oral plus pharyngeal anesthesia (P = 0.0005). We conclude that 1) neither elicitation of the pharyngeal swallow response nor temporal regulation among swallow events is dependent on mucosal sensory receptors and 2) duration of the pharyngeal contraction is influenced by sensory input from the oral-pharyngeal mucosa.

Expediting the early hospital care of the adult patient with nontraumatic chest pain: impact of a modified ED triage protocol

A prospective study that compared a traditional emergency department (ED) triage protocol with an expedited protocol was conducted to determine if minimizing the subjectivity of nursing triage would result in more efficient management of adult patients presenting with nontraumatic chest pain. The traditional protocol triaged 382 patients into 1 of 5 categories of acuity. The expedited study group (418 patients) were triaged as usual but subsequently were treated as if they were triage category 1 or 2 (medical evaluation within 15 minutes of arrival). Traditional triage led to 40% of acute myocardial infarction (AMI) patients being triaged into inappropriately low-acuity categories. The expedited protocol resulted in significant improvement in the following intervals: ED arrival to triage, triage to cubicle, ED arrival to cubicle, ED arrival to electrocardiogram (ECG) ordered, ED arrival to ECG available, ED arrival to physician evaluation, and ED arrival to decision to thrombolyse. Study patients with non-AMI cardiac chest pain and AMI cardiac chest pain were evaluated by a physician an average of 12 minutes and 8 minutes after ED arrival, respectively. Delays in interdepartmental processes, such as ECG-technician responsiveness, thrombolysis protocol fulfillment and thrombolytic agent delivery, negated benefits derived from improvements in internal processes. Effective coordination of the numerous processes involved in the initial ED management of adult patients with nontraumatic chest pain is required to make thrombolytic therapy for AMI within 30 minutes of patient arrival a routinely achievable goal.

Relevant factors in the identification of hearing loss

This study examined factors which may affect early identification of hearing loss. The medical records of 123 children with educationally significant hearing impairment were examined. Information about each child's degree and type of hearing loss, etiology, referral source, birth and medical history, additional handicaps, age of suspicion of loss, mode of identification, age of identification, and age at which aided was entered into a database for further analysis. The age range for identification was 7 weeks to 10 yr, with a median age of 2.1 yr. Children with a greater degree of hearing loss, an additional handicap, additional medical conditions, or an etiology strongly associated with hearing loss were identified earlier than those without these factors. Unexpectedly, children with a history of middle ear dysfunction were identified no later than those without, and children with a positive family history of hearing loss were identified later than those with a negative family history. These results agree with other studies which show that, in general, children are identified and habilitated at a later age than that recommended by both the American Speech-Language-Hearing Association Committee and the Joint Committee on Infant Hearing.

Blunt aortic trauma: signs of high risk

In the last 10 years, our center has managed 60 cases of aortic rupture from blunt chest trauma. Nineteen patients died (32%), 11 of whom were moribund on admission. Two patients out of ten who had undergone aortography at other institutions arrived at our hospital with massive bleeding in the left chest and died despite immediate operation. Six patients exsanguinated 1 to 2 1/2 hours after admission while aortography was being arranged or performed, and review of these cases to identify clinical signs of high risk revealed that left hemothorax, pseudocoarctation, and/or supraclavicular hematoma were present in five of the six. It appeared that the survival rate of patients suspected of blunt aortic trauma who had any of these clinical signs might be improved if they were taken directly to the operating room. To investigate this possibility we reviewed all cases from the past 10 years (excluding patients moribund on arrival or who had aortography elsewhere) in whom suspicion of aortic trauma led to aortography or surgery. Thirteen of the 17 patients (76%) with one or more signs of high risk had torn the aortic isthmus, compared to 26 of 154 patients (17%) without these signs. Five of the high-risk group (29%) exsanguinated, compared to one (less than 1%) of the others. No patient in this series died from unsuspected aortic trauma, which we attribute to the liberal use of aortography. Except for the patients with exsanguinating hemorrhage preoperatively, there were no operative or postoperative deaths.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatic vein bullet embolus as a complication of left thoracic gunshot injury

The case of a patient with a hepatic vein bullet embolus complicating a left ventricular gunshot injury is described. The patient presented hypotensive with a left midaxillary entrance wound. Initial radiographs showed a bullet fragment below the right hemidiaphragm. Emergency open thoracotomy was performed with release of a tense pericardial effusion and repair of a left ventricular penetrating wound. Surgical exploration failed to reveal direct penetrating injury to the diaphragm or abdominal viscera. After a hepatic venogram localized the bullet fragment in a branch of the right lobe hepatic vein, a periscopically directed catheter extraction of the fragment was successfully performed. A discussion of missile embolization, its pathology, clinical presentation, diagnosis, and management is presented.