Productive extension of semantic memory in school-aged children: Relations with reading comprehension and deployment of cognitive resources.

We investigated 7- to 10-year-old children's productive extension of semantic memory through self-generation of new factual knowledge derived through integration of separate yet related facts learned through instruction or through reading. In Experiment 1, an experimenter read the to-be-integrated facts. Children successfully learned and integrated the information and used it to further extend their semantic knowledge, as evidenced by high levels of correct responses in open-ended and forced-choice testing. In Experiment 2, on half of the trials, the to-be-integrated facts were read by an experimenter (as in Experiment 1) and on half of the trials, children read the facts themselves. Self-generation performance was high in both conditions (experimenter- and self-read); in both conditions, self-generation of new semantic knowledge was related to an independent measure of children's reading comprehension. In Experiment 3, the way children deployed cognitive resources during reading was predictive of their subsequent recall of newly learned information derived through integration. These findings indicate self-generation of new semantic knowledge through integration in school-age children as well as relations between this productive means of extension of semantic memory and cognitive processes engaged during reading. (PsycINFO Database Record

Development of memory for spatial locations and object/place associations in infant rhesus macaques with and without neonatal hippocampal lesions.

This study traces the development of spatial memory abilities in monkeys and reports the effects of selective neonatal hippocampal lesions on performance across development. Two different versions of the visual paired-comparison (VPC) task were used. The VPC-Spatial-Location task tested memory for object-locations that could be solved using an egocentric spatial frame of reference and the VPC-Object-In-Place task taxed memory for spatial relations using an allocentric reference frame. Eleven rhesus macaques (6 neonatal sham-operated controls and 5 with neonatal neurotoxic hippocampal lesions) were tested on both tasks as infants (8 months), juveniles (18 months), and adults (5-6 years). Memory for spatial locations was present by 18 months of age, whereas memory for object-place relations was present only in adulthood. Also, neonatal hippocampal lesions delayed the emergence of memory for spatial locations and abolished memory for object-place associations, particularly in animals that had sustained extensive and bilateral hippocampal lesions. The differential developmental time course of spatial memory functions and of the effects of neonatal hippocampal lesions on these functions are discussed in relation to morphological maturation of the medial temporal lobe structures in monkeys. Implications of the findings for the neural basis of spatial memory development in humans are also considered.

Clinical role of Cefixime in community-acquired infections.

UNLABELLED: Cefixime is an oral third generation cephalosporin, frequently used in respiratory tract infections (RTI) in the pediatric population. However, in some publications cefixime has demonstrated poor efficacy against staphylococci and streptococci. THE AIM: of this study was to evaluate the efficacy of cefixime in the treatment of community-acquired infections in a country where parenteral third generation cephalosporins have been used for a long time. The present study was designed to assess the clinical efficacy, bacteriological eradication rates and tolerability of cefixime in children with community-acquired upper RTI (URTI), lower RTI (LRTI) and uncomplicated urinary tract infections (UTI). MATERIALS AND METHODS: The study was prospective, open, and included 89 patients, from 6 months to 28 years, of both sexes, with the diagnosis of community-acquired URTI, LRTI and UTI. RESULTS: The treatment with cefixime was successful in 30/30 (100%) patients suffering from acute otitis media (AOM), in 10/12 (83.3%) with acute sinusitis, in 12/12 patients (100%) with pneumonia, in 31/35 (88.57) with uncomplicated UTI. The antibiotic was well tolerated. In 10 days treatment we recorded one case (1.3%) with acute gastroenteritis and two cases (2.6%) of maculopapular rash. Side-effects were transient and disappeared after finishing therapy in all three of the cases. CONCLUSIONS: Community-acquired infections, such as AOM, LRTI and UTI, caused by susceptible pathogens, can be treated with cefixime, as a good choice for a successful clinical response.

Emergent management of acute asthma.

In almost no other field is the gap between diagnostic and therapeutic knowledge and its general application so great as it is in asthma. As previously mentioned, most asthma deaths are preventable. Identification of high-risk patients, intensive education about asthma (purpose of each medication; necessity of compliance, particularly with inhaled corticosteroids; proper use of inhalers and spacer devices; home use of PEFR meter), self-treatment of mild or moderate attacks with oral corticosteroids, and written crisis plan for severe attacks explicitly telling the patient what to do and whom to call are necessary. In addition, all potential exacerating factors should be eliminated (external triggers, medication, gastroesophageal reflux, allergic rhinitis, and sinusitis). High doses of inhaled corticosteroids should be provided to all those patients, and referral to a specialist is highly recommended for such high-risk patients.

Comprehensive long-term management program for asthma: effect on outcomes in adult African-Americans.

To determine if a comprehensive long-term management program, emphasizing inhaled corticosteroids and patient education, would improve outcomes in adult African-American asthmatics a nonrandomized control trial with a 2-year intervention was performed in a university-based clinic. Inclusion criteria consisted of (> or = 5) emergency department (ED) visits or hospitalizations (> or = 2) during the previous 2 years. Intervention patients were volunteers; a comparable control group was identified via chart review at hospitals within the same area and time period as the intervention patients. Individualized doses of beclomethasone with a spacer, inhaled albuterol "as needed," and crisis prednisone were the primary therapies. Environmental control, peak flow monitoring, and a partnership with the patient were emphasized. Detailed patient education was an integral part of management. Control patients received usual care from local physicians. ED visits and hospitalizations for 2 years before and 2 years during the intervention period were compared. Quality of life (QOL) measurements were made at baseline and every 6 months in the intervention group. Study group (n = 21) had a significant reduction in ED visits (2.3 +/- 0.2 pre-intervention versus 0.6 +/- 0.2 post-intervention; P = 0.0001). Control group (n = 18) did not have a significant change in ED visits during the 2-year post-intervention period (2.6 +/- 0.2 pre-intervention versus 2.0 +/- 0.2 post-intervention; P = 0.11). Both groups had significant reductions in hospitalizations, but the study group had a greater reduction. Sixty-two percent of study patients had complete elimination of ED visits and hospitalizations, whereas no control patients had total elimination of the need for institutional acute care. QOL in the study patients revealed significant improvements for most parameters. A comprehensive long-term management program emphasizing inhaled corticosteroids combined with other state-of-the-art management, including intensive patient education, improves outcomes in adult African-American asthmatics.

Noninvasive mechanical ventilation in patients with acute respiratory failure.

OBJECTIVES: a) To describe the introduction of noninvasive means to provide positive-pressure ventilation in acute respiratory failure; b) to describe the physiologic response to noninvasive ventilation; c) to review the current published literature on using noninvasive ventilation in patients with acute hypercapnic and/or hypoxemic respiratory failure; d) to describe the technique of applying mask ventilation and current recommendations for using noninvasive ventilation and current recommendations for using noninvasive ventilation in patients with acute respiratory failure; and e) to discuss the advantages and disadvantages of noninvasive ventilation. DATA SOURCES: All relevant articles published in the English medical literature from 1988 through August 1994 were retrieved through a MEDLINE search, as well as from the author's experience. STUDY SELECTION: Studies were selected based on the use of positive-pressure mechanical ventilation delivered, using facial or nasal masks in various acute settings of respiratory failure. DATA EXTRACTION: The authors extracted all applicable data. DATA SYNTHESIS: Studies were analyzed according to the type of respiratory failure (hypercapnic vs. hypoxemic) and underlying conditions where noninvasive ventilation seemed to be a better alternative. The results were evaluated based on types of masks used and modes of ventilation. Outcome measures were compared based on studies that randomized patients with acute respiratory failure to receive noninvasive vs. conventional therapy. Complications of noninvasive ventilation, mainly local, were compared with those complications seen endotracheal intubation in acute respiratory failure patients. CONCLUSIONS: Noninvasive ventilation is a safe and effective means of ventilatory support for many patients with acute respiratory failure. Noninvasive ventilation is well tolerated, principally because it allows the patient to be in control and to continue verbal communication, and should be strongly considered in managing terminally ill patients with potentially reversible causes of respiratory failure. The duration of mechanical ventilation and its associated complications are significantly decreased in hypercapnic respiratory failure with noninvasive ventilation.

Noninvasive positive pressure ventilation via face mask. First-line intervention in patients with acute hypercapnic and hypoxemic respiratory failure.

OBJECTIVES: We have previously reported our experience with noninvasive positive pressure ventilation (NPPV) via face mask in a small group of selected patients with acute respiratory failure (ARF). NPPV was frequently effective (70% success rate) in correcting gas exchange abnormalities and in avoiding endotracheal intubation (ETI); NPPV also had a low rate of complications. We have evaluated the clinical application of NPPV as first-line intervention in patients with hypercapnic and short-term hypoxemic ARF. A dedicated respiratory therapist conducted an educational program with physicians-in-training rotating through the medical ICUs of a university medical center and supervised implementation of a simplified management protocol. Over 24 months, 164 patients with heterogeneous forms of ARF received NPPV. We report on the effectiveness of NPPV in correcting gas exchange abnormalities, in avoiding ETI, and associated complications, in different conditions precipitating ARF. PATIENT POPULATION: One hundred fifty-eight patients completed the study. Forty-one had hypoxemic ARF, 52 had hypercapnic ARF, 22 had hypercapnic acute respiratory insufficiency (ARI), 17 had other forms of ARF, and 26 with advanced illness had ARF and refused intubation. Twenty-five percent of the patients developed ARF after extubation. INTERVENTION: Mechanical ventilation was delivered via a face mask. Initial ventilatory settings were continuous positive airway pressure (CPAP) mode, 5 cm H2O, with pressure support ventilation of 10 to 20 cm H2O titrated to achieve a respiratory rate less than 25 breaths/min and an exhaled tidal volume of 7 mL/kg or more. Ventilator settings were adjusted following arterial blood gases (ABG) results. RESULTS: The mean duration of NPPV was 25 +/- 24 h. When the 26 patients with advanced illness are excluded, NPPV was effective in improving or correcting gas exchange abnormalities in 105 patients (80%) and avoiding ETI in 86 (65%). Failure to improve ABG values was the reason for ETI in 20 of 46 (43%). The overall average predicted and actual mortality were 32% and 16%, respectively. Survival was 93% in non-intubated patients and 79% in intubated patients. NPPV was effective in lessening dyspnea throughout treatment in all but seven patients. Complications developed in 24 patients (16%). In patients with hypercapnic ARF, nonresponders had a higher PaCO2 at entrance (91.5 +/- 4.2 vs 80 +/- 1.5; p < 0.01). In patients with hypercapnic ARF and ARI, arterial blood gases response (pH and PaCO2) within 2 h of NPPV predicted success (p < 0.0001). None of the entrance parameters predicted need for ETI. CONCLUSIONS: We conclude that application of NPPV in clinical practice is an effective and safe alternative to ETI in many hemodynamically stable patients with hypercapnic ARF and in those with hypoxemic ARF in whom the clinical condition can be readily reversed in 48 to 72 h. An educational and supervision program is essential to successfully implement this form of therapy.

Diagnosis and management of acute asthma.

Deaths from asthma are relatively uncommon but have continued to rise worldwide in the past few decades, despite a better understanding of the disease and an increased number of patient medications. This often is attributed to inadequate assessment and treatment of the disease. This article focuses on defining several items that pertain to acute severe asthma. In addition, the pathophysiology and clinical manifestation of acute asthma, as well as current investigational tools, are reviewed. Traditional and nontraditional therapies of acute asthma are discussed. Finally, complications of severe asthma and the long-term outcome are discussed, with appropriate preventive measures stressed strongly.

Noninvasive mechanical ventilation via face mask in patients with acute respiratory failure who refused endotracheal intubation.

OBJECTIVE: To evaluate the response to noninvasive ventilation in a group of terminally ill patients with acute respiratory failure who refused endotracheal intubation. DESIGN: Case series. SETTING: Medical intensive care units (ICUs) in a university health science center. PATIENTS: Eleven patients, nine with hypercapnic and two with hypoxemic acute respiratory failure. Mean age of patients was 64 yrs. INTERVENTION: Mechanical ventilation was delivered via a face mask. The initial ventilatory setting was continuous positive airway pressure mode, with pressure-support ventilation of 10 to 20 cm H2O, titrated to achieve a respiratory rate of < 25 breaths/min and a tidal volume of 5 to 7 mL/kg. Ventilatory settings were adjusted based on results of arterial blood gases. Mean duration of mechanical ventilation was 44 hrs. MEASUREMENTS AND MAIN RESULTS: Mechanical ventilation via face mask was effective in correcting gas exchange abnormalities in seven of 11 patients, all of whom survived and were discharged from the ICU. Four patients with hypercapnic acute respiratory failure died. Mechanical ventilation via face mask was effective in improving respiratory acidosis in three patients and had no effect in one patient. Two of the four patients could not be weaned from mechanical ventilation and opted for discontinuation of this method. Removal of the ventilator while retaining the mask for oxygen supplementation was a nontraumatic experience to the patient and family. Even when respiratory failure did not resolve, mechanical ventilation via face mask was effective in lessening dyspnea and allowed the patient to maintain autonomy and continuous verbal communication. CONCLUSIONS: We conclude that mechanical ventilation via face mask offers an effective, comfortable, and dignified method of supporting patients with end-stage disease and acute respiratory failure.

Reassessing the therapeutic range for theophylline on laboratory report forms: the importance of 5-15 micrograms/ml.

The therapeutic status of theophylline has changed dramatically over the last decade. As part of this change, a different view of the most appropriate therapeutic range for serum theophylline concentration (STC) has emerged. The National Institutes of Health Expert Panel Report, "Guidelines for the Diagnosis and Management of Asthma," suggests a conservative approach of aiming for STC of 5-15 micrograms/ml. This truly landmark document along with several studies in the literature, recently prompted us to change our hospital's laboratory report form for the medical record to read that the therapeutic range for STC is 5-15 micrograms/ml. We encourage hospital laboratories or other clinical laboratories who have not already made this change to do so.

Two- and four-day rifampin chemoprophylaxis regimens induce oxidative metabolism.

The effects of two short-term chemoprophylaxis regimens of rifampin (2 or 4 days) on oxidative metabolism were investigated in 14 healthy subjects. Seven subjects received 600 mg of rifampin twice daily on study days 6 and 7 (group A), and seven subjects received 600 mg of rifampin once daily on days 4, 5, 6, and 7 (group B). Antipyrine (18 mg/kg of body weight) was administered orally on days 1, 8, and 15. Short-term rifampin regimens increased oral clearance of antipyrine in both groups compared with the baseline value (P less than 0.05), and group B displayed a larger percent increase over the baseline value than group A did (70.5 +/- 14.3 versus 33.1 +/- 18.1; P less than 0.05). The partial metabolic clearance (CLM) of antipyrine to 3-hydroxymethylantipyrine (HMA) on day 8 increased 71 and 108% for regimens A and B, respectively (P less than 0.05 for both). The corresponding increases in CLM to norantipyrine (NORA) were 57 and 98% (P less than 0.05 for both). CLM to 4-hydroxyantipyrine (OHA) on day 8 increased 64% for regimen A (P = 0.08) and 97% for regimen B (P less than 0.05) compared with the baseline. Although CLM to HMA and OHA on day 15 remained greater than 50% over the baseline with both regimens, CLM to NORA on day 15 was less than 25% over the baseline with both regimens. Thus, both short-term rifampin chemoprophylaxis regimens increased antipyrine clearance for at least 1 week. The increase tended to be higher with the 4-day regimen. The pattern observed for the CLMS suggests that more than one P-450 enzyme is affected.

Noninvasive face mask mechanical ventilation in patients with acute hypercapnic respiratory failure.

Mechanically assisted intermittent positive-pressure ventilation effectively provides ventilatory support in patients with respiratory failure but it requires placing an artificial airway. We have previously reported our successful experience delivering mechanical ventilation via a face mask (FMMV) rather than with an endotracheal tube in a pilot study of patients with acute respiratory failure. The present investigation evaluated an additional 18 patients with hypercapnic respiratory failure to determine the efficacy of FMMV in a more homogeneous group and to determine factors predicting its success. FMMV was successful in avoiding intubation in 13 of the 18 patients. A significant initial improvement in PCO2 (greater than 16 percent decrease) and in pH (from less than 7.30 to greater than 7.30) predicted success. The five patients who failed on FMMV required endotracheal intubation because of inability to improve gas exchange (three patients), apnea due to sedatives (one patient), and management of secretions (one patient). FMMV was generally well accepted with only two patients withdrawn because of intolerance of the mask. The mean duration of FMMV was 25 h. Complications were seen in only two patients (11 percent): aspiration (one patient) and mild skin necrosis (one patient). Seven patients entered the study by meeting entrance criteria after an unsuccessful extubation attempt and therefore received both forms of mechanical ventilation. All but one patient avoided reintubation, and the face mask proved to be as effective as the endotracheal tube as a conduit for delivering the mechanical tidal volume and improving gas exchange. Our findings indicate that FMMV is a viable option for short-term (one to four days) ventilatory support of patients with hypercapnic respiratory failure and insufficiency.

Inhaled albuterol and oral prednisone therapy in hospitalized adult asthmatics. Does aminophylline add any benefit?

STUDY OBJECTIVE: To determine the efficacy of intravenous aminophylline in the treatment of adult patients hospitalized for exacerbation of asthma. DESIGN: Randomized, double-blind, placebo-controlled trial throughout the study. SETTING: University Hospital Clinical Research Center. PATIENTS: Forty-four patients admitted from the emergency room with a primary diagnosis asthma; 39 patients completed the study. INTERVENTIONS: Patients received either intravenous aminophylline or placebo in addition to frequent nebulized albuterol; prednisone 0.5 mg/kg body weight every 6 h orally; and supplemental oxygen. Aminophylline infusion rates were adjusted to achieve serum theophylline concentrations of 10 to 20 micrograms/ml. Changes were made in placebo infusion rates to maintain the double blind design. MEASUREMENTS AND RESULTS: Forced expiratory volume in 1 s (FEV1) and other spirometric measurements every 8 h by a blinded investigator or trained respiratory therapist. Subjective patient response and duration of hospitalization were compared. No difference in spirometric measurements was observed between the two groups at any time point. On admission to the study, FEV1 in the placebo group was 41.5 (+/- 2.9) percent predicted and in the aminophylline group 34.7 (+/- 2.3) percent predicted (p = 0.08). At discharge, FEV1 was 70.4 (+/- 2.9) percent predicted in the placebo group and 63.7 (+/- 2.8) percent predicted in the theophylline group (p = 0.10). There was no difference in subjective patient rating or duration of hospitalization between the two groups (placebo 1.95 days and aminophylline 1.78 days, p = 0.51). CONCLUSIONS: Our results suggest that aminophylline therapy does not add significant benefit to other standard therapies in hospitalized adult asthmatic patients. Because of the risks and cost of aminophylline treatment in the hospital setting, further research is needed to determine if there are subgroups of adult asthmatics who may benefit from the addition of aminophylline to other standard optimal therapies.

Is theophylline use justified in acute exacerbations of asthma?

Despite widespread use of theophylline in the hospital management of asthma, supportive data justifying its use are sparse. Clinical research in the 1980s has forced a serious new examination of the drug's role in acute exacerbations of asthma. Because of the morbidity, mortality, questionable value, and overall cost of theophylline therapy, this reevaluation is of particular importance. Enhanced knowledge of the value of treatment with intensive inhaled beta agonists, systemic glucocorticoids, and inhaled ipratropium should prompt elimination of the routine, initial use of theophylline in emergency room care of most asthmatics. Further research is necessary to justify the routine, initial use of the drug in hospitalized asthmatics.