Catheter management after benign transurethral prostate surgery: RAND/UCLA Appropriateness Criteria

OBJECTIVES

To formally assess the appropriateness of different timings of urethral catheter removal after transurethral prostate resection or ablation. Although urethral catheter placement is routine after this common treatment for benign prostatic hyperplasia (BPH), no guidelines inform duration of catheter use.

STUDY DESIGN

RAND/UCLA Appropriateness Methodology.

METHODS

Using a standardized, multiround rating process (ie, the RAND/UCLA Appropriateness Methodology), an 11-member multidisciplinary panel reviewed a literature summary and rated clinical scenarios for urethral catheter duration after transurethral prostate surgery for BPH as appropriate (ie, benefits outweigh risks), inappropriate, or of uncertain appropriateness. We examined appropriateness across 4 clinical scenarios (no preexisting catheter, preexisting catheter [including intermittent], difficult catheter placement, significant perforation) and 5 durations (postoperative day [POD] 0, 1, 2, 3-6, or ≥7).

RESULTS

Urethral catheter removal and first trial of void on POD 1 was rated appropriate for all scenarios except clinically significant perforations. In this case, waiting until POD 3 was deemed the earliest appropriate timing. Waiting 3 or more days to remove the catheter for patients with or without preexisting catheter needs, or for those with difficult catheter placement in the operating room, was rated as inappropriate.

CONCLUSIONS

We defined clinically relevant guidance statements for the appropriateness of urethral catheter duration after transurethral prostate surgery. Given the lack of guidelines and this robust expert panel approach, these ratings may help clinicians and healthcare systems improve the consistency and quality of care for patients undergoing transurethral surgery for BPH.

How often are health care personnel hands colonized with multidrug- resistant organisms? A systematic review and meta-analysis

BACKGROUND

Hands of health care personnel (HCP) can transmit multidrug-resistant organisms (MDROs), resulting in infections. Our aim was to determine MDRO prevalence on HCP hands in adult acute care and nursing facility settings.

METHODS

A systematic search of PubMed/MEDLINE, Web of Science, CINAHL, Embase, and Cochrane CENTRAL was performed. Studies were included if they reported microbiologic culture results following HCP hands sampling; included prevalent MDROs, such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus, Clostridium difficile, Acinetobacter baumannii, or Pseudomonas aeruginosa, and were conducted in acute care or nursing facility settings.

RESULTS

Fifty-nine articles comprising 6,840 hand cultures were included. Pooled prevalence for MRSA, P aeruginosa, A baumannii, and vancomycin-resistant Enterococcus were 4.26%, 4.59%, 6.18%, and 9.03%, respectively. Substantial heterogeneity in rates of pathogen isolation were observed across studies (I² = 81%-95%). Only 4 of 59 studies sampled for C difficile, with 2 of 4 finding no growth. Subgroup analysis of MRSA revealed the highest HCP hand contamination rates in North America (8.28%). Sample collection methods used were comparable for MRSA isolation (4%-7%) except for agar direct contact (1.55%).

CONCLUSIONS

Prevalence of common MDROs on HCP hands vary by pathogen, care setting, culture acquisition method, study design, and geography. When obtained at an institutional level, these prevalence data can be utilized to enhance knowledge, practice, and research to prevent health care-associated infections.

Michigan Appropriate Perioperative (MAP) criteria for urinary catheter use in common general and orthopaedic surgeries: results obtained using the RAND/UCLA Appropriateness Method

BACKGROUND

Indwelling urinary catheters are commonly used for patients undergoing general and orthopaedic surgery. Despite infectious and non-infectious harms of urinary catheters, there is limited guidance available to surgery teams regarding appropriate perioperative catheter use.

OBJECTIVE

Using the RAND Corporation/University of California Los Angeles (RAND/UCLA) Appropriateness Method, we assessed the appropriateness of indwelling urinary catheter placement and different timings of catheter removal for routine general and orthopaedic surgery procedures.

METHODS

Two multidisciplinary panels consisting of 13 and 11 members (physicians and nurses) for general and orthopaedic surgery, respectively, reviewed the available literature regarding the impact of different perioperative catheter use strategies. Using a standardised, multiround rating process, the panels independently rated clinical scenarios (91 general surgery, 36 orthopaedic surgery) for urinary catheter placement and postoperative duration of use as appropriate (ie, benefits outweigh risks), inappropriate or of uncertain appropriateness.

RESULTS

Appropriateness of catheter use varied by procedure, accounting for procedure-specific risks as well as expected procedure time and intravenous fluids. Procedural appropriateness ratings for catheters were summarised for clinical use into three groups: (1) can perform surgery without catheter; (2) use intraoperatively only, ideally remove before leaving the operating room; and (3) use intraoperatively and keep catheter until postoperative days 1-4. Specific recommendations were provided by procedure, with postoperative day 1 being appropriate for catheter removal for first voiding trial for many procedures.

CONCLUSION

We defined the appropriateness of indwelling urinary catheter use during and after common general and orthopaedic surgical procedures. These ratings may help reduce catheter-associated complications for patients undergoing these procedures.

Review of Strategies to Reduce Central Line-Associated Bloodstream Infection (CLABSI) and Catheter-Associated Urinary Tract Infection (CAUTI) in Adult ICUs

Central line-associated bloodstream infection (CLABSI) and catheter-associated urinary tract infection (CAUTI) are costly and morbid. Despite evidence-based guidelines, Some intensive care units (ICUs) continue to have elevated infection rates. In October 2015, we performed a systematic search of the peer-reviewed literature within the PubMed and Cochrane databases for interventions to reduce CLABSI and/or CAUTI in adult ICUs and synthesized findings using a narrative review process. The interventions were categorized using a conceptual model, with stages applicable to both CAUTI and CLABSI prevention: (stage 0) avoid catheter if possible, (stage 1) ensure aseptic placement, (stage 2) maintain awareness and proper care of catheters in place, and (stage 3) promptly remove unnecessary catheters. We also looked for effective components that the 5 most successful (by reduction in infection rates) studies of each infection shared. Interventions that addressed multiple stages within the conceptual model were common in these successful studies. Assuring compliance with infection prevention efforts via auditing and timely feedback were also common. Hospitalists with patient safety interests may find this review informative for formulating quality improvement interventions to reduce these infections.

Systematic Review of Interventions to Reduce Urinary Tract Infection in Nursing Home Residents

BACKGROUND

Urinary tract infections (UTIs) in nursing homes are common, costly, and morbid.

PURPOSE

Systematic literature review of strategies to reduce UTIs in nursing home residents.

DATA SOURCES

Ovid MEDLINE, Cochrane Library, CINAHL, Web of Science and Embase through June 22, 2015.

STUDY SELECTION

Interventional studies with a comparison group reporting at least 1 outcome for: catheter-associated UTI (CAUTI), UTIs not identified as catheter-associated, bacteriuria, or urinary catheter use.

DATA EXTRACTION

Two authors abstracted study design, participant and intervention details, outcomes, and quality measures.

DATA SYNTHESIS

Of 5794 records retrieved, 20 records describing 19 interventions were included: 8 randomized controlled trials, 10 pre-post nonrandomized interventions, and 1 nonrandomized intervention with concurrent controls. Quality (range, 8-25; median, 15) and outcome definitions varied greatly. Thirteen studies employed strategies to reduce catheter use or improve catheter care; 9 studies employed general infection prevention strategies (eg, improving hand hygiene, surveillance, contact precautions, reducing antibiotics). The 19 studies reported 12 UTI outcomes, 9 CAUTI outcomes, 4 bacteriuria outcomes, and 5 catheter use outcomes. Five studies showed CAUTI reduction (1 significantly); 9 studies showed UTI reduction (none significantly); 2 studies showed bacteriuria reduction (none significantly). Four studies showed reduced catheter use (1 significantly).

LIMITATIONS

Studies were often underpowered to assess statistical significance; none were pooled given variety of interventions and outcomes.

CONCLUSIONS

Several practices, often implemented in bundles, such as improving hand hygiene, reducing and improving catheter use, managing incontinence without catheters, and enhanced barrier precautions, appear to reduce UTI or CAUTI in nursing home residents. Journal of Hospital Medicine 2017;12:356-368.

Methadone in the treatment of chronic nonmalignant pain: a 2-year follow-up

OBJECTIVE

To examine the longitudinal use of methadone in a pain clinic.

DESIGN

Follow-up study of 40 patients initially treated with methadone and re-evaluated 2 years later, comparing those maintained on methadone with those who were switched to other opioids.

SETTING

Pain clinic at a university hospital.

RESULTS

The 14 patients (35%) who stayed on methadone for the duration of the study, had higher employment rates (P <.05) and higher functional ratings (P <.02) than those on other opioids. Side effects were the most common reason (33.4%) for discontinuation of methadone. Dose escalation occurred in 11 of 14 patients (78.6%).

CONCLUSIONS

Chronic pain patients may be safely and effectively treated with methadone. Those not responding or tolerating methadone may be benefited by treatment with other opioids.

Pain management issues: the cost of medications in rural settings

Cost of analgesic and adjuvant medications used by rural patients with cancer cared for by 29 nurses participating in an in-depth education program were evaluated before and after the program. Across all time periods, the median daily cost was $5.16 across all medications. Average daily cost and maximum and median cost of all medications were $5.36, $74.38 and $3.58, respectively. Average daily cost did not change over time. Average pain intensity did not change over time and was not related to prescribing patterns or daily costs. While professional education was demonstrated to produce change in prescribing practices, further research is needed to evaluate patterns of medication administration and effectiveness patterns using reliable outcome measures other than self report of pain intensity.

Successful treatment of headache related to intravenous immunoglobulin with antimigraine medications

In order to investigate headache related to intravenous immunoglobulin, we studied a 36-year-old woman with a history of migraine receiving weekly intravenous immunoglobulin for refractory myasthenia gravis who experienced severe headaches with each treatment. Neurological examination, CT scan of the head, and a lumber puncture after the first headache were normal. Significant therapeutic response was based upon 50% reduction in pain and associated features. Headache features included throbbing pain which worsened with head movement and was associated with severe photophobia and nausea. Sumatriptan, 6 mg subcutaneous, reduced headache significantly with resolution of associated complaints. Treatment prior to intravenous immunoglobulin with dihydroergotamine mesylate resulted in development of only a mild dull ache without further development of severe head pain. Dihydroergotamine mesylate was also abortive in the few instances when the headache worsened. Headaches associated with intravenous immunoglobulin may have features of migraine and may be successfully prevented and/or treated with 5-HT1D receptor agonists.

An examination of nursing attitudes and pain management practices

PURPOSE

The purpose of this evaluation is to examine the relationship among nurses' pain management attitudes and pain management practices and to begin to explore the theoretical underpinnings that may influence this relationship.

DESCRIPTION OF STUDY

A convenience sample of 29 female registered nurses working in hospice or home health settings participated in an educational program 1 day per week for 6 weeks. All participants were asked to complete the Cancer Pain Knowledge Inventory and Survey of Expectations and Pain Assessment Questionnaire 5 weeks before, immediately before, immediately after, 6 months after, and 12 months after the program. Seventeen participants completed all questionnaires at the 6-month follow-up; 16 participants completed all questionnaires at the 1-year follow-up. Personal beliefs about pain were evaluated in relation to the dimensions and treatment of pain. Intentions and expectations to perform specific activities were evaluated in relation to in-depth assessments, equianalgesic conversions, demonstration of new ideas, and communication.

RESULTS

Nurses' attitudes, beliefs, intentions, and expectations about pain and pain management influenced nurses' patient care and educational activities. Nurses who believed that patients should be pain free and nurses who focused on both the dimensions and treatment of pain implemented more pain management activities. In general, nurses who had high intentions and expectations performed more pain management activities.

CLINICAL IMPLICATIONS

Although nurses reported change in attitude, and high expectancy for change, feelings of increased credibility, and increased motivation as advocates for new approaches to practice, nurses sometimes found it difficult to implement new practices because of constraints in time and collaborative efforts. To implement new knowledge and achieve individualized goals for change, nurses must be allowed adequate time to analyze the relationships between their beliefs about pain and the ways that they solve patients' pain problems. In addition, more support for multidisciplinary collaboration is needed.

Changing the relationship among nurses' knowledge, self-reported behavior, and documented behavior in pain management: does education make a difference?

An educational program designed to change knowledge in order to change pain management practices and patient outcomes was offered to nurses who provide day-to-day care to patients with cancer in communities in a predominantly rural state. A quasi-experimental time-series design was used to measure the effectiveness of the program in changing nurse knowledge, attitude and behavior, and to evaluate the relationships between the outcomes. Data were collected from nurses (N = 29) and patient charts before (N = 209) and after (N = 163) the program. Nurses' knowledge increased, but the change was not statistically significant; the mean percent of correct answers on the three subtests were different and differences persisted throughout the study. Nurses believed that patients should be "pain free." Documentation of behaviors, for example, practice activities, occurred infrequently and showed little change until 6 months after the program. Increase in documentation of pain-intensity ratings, pain location, number of sites of pain, presence of confusion, anxious or depressed mood, sleep, nausea and vomiting, constipation, and general activity were noted. Documentation of the use of a propoxyphene-containing analgesic decreased; increase in the use of hydromorphone methadone and transdermal fentanyl was noted. Analysis of the relationships between correct responses to nurse knowledge questions and documentation of behavior provided interesting, statistically insignificant results that need to be reexamined in future research. Future programs should emphasize analgesic dosing and calculation of equianalgesic doses. Current practices in chart documentation may provide incomplete information regarding change in practice behaviors; more detailed documentation of pain management practices is needed. Nurses who participated in the program anecdotally reported feelings of increased credibility and effectiveness. Although change in behavior is slow to occur, education does make a difference.

Relationship of learned resourcefulness to measures of pain description, psychopathology and health behavior in a sample of chronic pain patients

OBJECTIVE

We investigated the association between the coping style of learned resourcefulness and the variables of pain description, pain locus of control, psychological distress, and health-care utilization.

DESIGN

A cross-sectional, retrospective, correlational design was used.

PATIENTS AND SETTING

The sample was comprised of 87 outpatients from a university-based, multidisciplinary pain clinic.

MAIN OUTCOME MEASURES

Self-Control Schedule, pain intensity, McGill Pain Questionnaire, Pain Locus of Control Scale, SCL-90-R, Health-Care Utilization Questionnaire.

RESULTS AND CONCLUSIONS

Results indicated that chronic pain patients obtained comparable resourcefulness ratings to normal subjects but there were wide individual differences. Consistent with theoretical predictions, resourcefulness was found to be associated with better psychological adjustment and less impulsive health-care measures. Results suggest that assessment of learned resourcefulness may be useful in predicting behavioral outcome in clinical settings with chronic pain patients.

Relationship of sexual and physical abuse to pain description, coping, psychological distress, and health-care utilization in a chronic pain sample

OBJECTIVE

We investigated the association of physical/sexual abuse to pain description, coping, psychological distress, and health-care utilization in a heterogeneous sample of chronic pain patients.

DESIGN

A cross-sectional, retrospective design was used. Patients were categorized as abused (n = 22) or nonabused (n = 58) based on responses to a valid and reliable sexual/physical abuse questionnaire.

MAIN OUTCOME MEASURES

Pain description (Visual Analog Scale measures of pain intensity and frequency, and the McGill Pain Questionnaire); coping ability and attributional style (Functional Interference Estimate, Self-Control Schedule, Pain Locus of Control Scale); psychological distress (SCL-90-R Global Severity Index); and a Health-care utilization measure.

RESULTS AND CONCLUSIONS

No differences between abused and nonabused groups were found for the pain description or functional interference variables. Compared to the nonabused group, the abused group had significantly lower Self-Control Schedule scores, higher Pain Locus of Control Scale Chance Factor scores, and higher SCL-90-R Global Severity Index scores and was more likely to use the emergency room for pain symptoms. These results replicate the findings of previous studies of the effects of abuse in more specific pain samples and underscore the importance of assessment of abuse in patients with chronic pain. The data suggest that interventions which involve coping-skills training or self-control management of pain may be affected by an abuse history via reduced perceptions of efficacy, resourcefulness, and beliefs that external variables are responsible for pain.

Managing cancer pain: content and scope of an educational program for nurses who work in predominantly rural areas

A great deal of effort is being expended at national, state and local levels to improve cancer pain management in the United States. The fact that cancer patients continue to experience "unrelieved pain" is of concern to professional caregivers and families, as well as to the patients themselves. This article describes the content and scope of an educational program for nurses who work in predominantly rural areas. Content of the program and the evaluation process are described in detail in order to provide other caregivers with a model that could be implemented in similar settings.

Psychometric characteristics of a brief measure of pain-related functional impairment

This study presents reliability and validity data from two samples (pain clinic vs medical clinic) on a five-item self-report scale, termed the Functional Interference Estimate (FIE), designed to measure functional impairment associated with chronic pain. Results from the pain clinic sample demonstrated that the FIE is internally consistent and has satisfactory levels of test-retest reliability, item-total score correlations, and convergent validity. Results from the medical clinic sample demonstrated that the FIE discriminated between medical clinic patients without pain and both medical clinic patients with pain and pain clinic patients. The data support the use of the FIE as one of several available assessment methods for evaluation of pain-related functional impairment.

Pain locus of control scores in chronic pain patients and medical clinic patients with and without pain

OBJECTIVE

We investigated the association between treatment setting and pain control attributions as assessed by the Pain Locus of Control Scale (PLOC).

DESIGN

Nonrandomized consecutive samples.

PATIENTS AND SETTING

The patient groups included an outpatient pain clinic sample of chronic pain patients (n = 48), a group of medical clinic outpatients with chronic pain (n = 28), and a group of medical clinic outpatients without current pain (n = 22). Medical clinic patients without current pain were asked to reply to the PLOC items in terms of their usual response when experiencing pain.

RESULTS AND CONCLUSIONS

Results indicated that pain clinic patients were the least likely of the three groups to report predictable control of their pain as reflected by their significantly lower "powerful other" and higher "chance" dimension scores. Medical clinic patients without pain reported greater personal control of pain than the other two groups as evidenced by their higher "internality" dimension score and lower "chance" dimension score. Results indicate that pain control appraisals differ among patients with chronic pain and illness as a function of the treatment setting and suggest that differences in cognitive appraisal can affect treatment efficacy.

Extrarenal Wilms' tumor. Unusual presentation in the lumbosacral region

True extrarenal Wilms' tumor is a rare malignant neoplasm most frequently presenting in the retroperitoneal or inguinal regions. We report an unusual subcutaneous lumbosacral (LS) region extrarenal Wilms' tumor without associated teratomatous tumor elements or associated neural tube defect in a 2 1/2-year-old girl. Pathologic review revealed features of true extrarenal Wilms' tumor, and the patient remains in complete remission following surgery and combination chemotherapy. This report illustrates the importance of early surgical intervention and pathologic examination of similar soft tissue masses in children.

Octanoic Acid Produces Accumulation of Monoamine Acidic Metabolites in the Brain: Interaction with Organic Anion Transport at the Choroid Plexus

Effects of octanoic acid on monoamines and their acidic metabolites in the rat brain were analyzed by HPLC. Octanoic acid (1,000 mg/kg i.p.) elevated homovanillic acid levels by 54% in the caudate and 338% in the hypothalamus but increased 5-hydroxyindoleacetic acid (5-HIAA) levels in both the caudate and the hypothalamus by approximately 50% compared with the control. A lower dose of octanoic acid (500 mg/kg) increased 5-HIAA levels by 29% in the caudate and 20% in the hypothalamus. However, it did not produce any changes in the concentration of homovanillic acid in either the caudate or the hypothalamus. Treatment with octanoic acid also failed to change the level of dopamine, serotonin, and 3,4-dihydroxyphenylacetic acid in the caudate and the hypothalamus. The role of carrier-mediated transport in the clearance of 5-HIAA from the rabbit CSF was also evaluated in vivo by ventriculocisternal perfusion. Steady-state clearance of 5-HIAA from CSF exceeded that of inulin and was reduced in the presence of octanoic acid. Because this transport system in the choroid plexus is normally responsible for the excretion of the serotonin metabolite from the brain to the plasma, accumulation of endogenously produced organic acids in the brain, secondary to reduced clearance by the choroid plexus, could be a contributing factor in the development of encephalopathy in children with medium-chain acyl-CoA dehydrogenase deficiency who have elevated levels of octanoic acid systematically.

Relationship of pain drawing scores to ratings of pain description and function

We examined the relationship between pain distribution and measures of self-reported behavioral functioning, pain intensity, frequency, and quality in 51 patients with chronic pain. Results indicate that patients with more distributed pain report their pain as more disruptive to important areas of functioning and also report their pain as more intense and frequent. These results corroborate previous findings and suggest that pain distribution may be used as a useful clinical marker of disability status in chronic pain patients.

Relationship between perceived self-control of pain, pain description and functioning

Recent research has shown an association between preferred coping style and pain report. The present study explores in a sample of 51 patients with chronic pain of myofascial origin the relationship between a dispositional measure of coping, the internality dimension of the Pain Locus of Control Scale (PLOC), and ratings of pain intensity, frequency, and pain-related behavioral functioning. Patients above the median on the internality dimension of the PLOC reported their pain as less intense and frequent than those below the median. No differences were noted on the behavioral functioning measures. Results are consistent with previous studies and indicate an association between ability to control pain and variations in magnitude and periodicity of pain. The clinical implication of the data is that strategies which provide reduction in pain intensity and frequency might be expected to result in increased perception of personal control of pain.

A nonlinear least-squares method for determining cerebrospinal fluid formation and absorption kinetics in pseudotumor cerebri

Data from 14 patients with benign intracranial hypertension (pseudotumor cerebri) have been analyzed using a nonlinear least-squares regression model which was developed and programmed from in-hospital microcomputer use. The method of analysis permits rapid estimation of cerebrospinal fluid (CSF) formation and absorption rates as functions of pressure in individual patients using data from constant-rate infusion manometrics. The analysis predicts that prednisone therapy in pseudotumor cerebri reduces resting CSF pressure by increasing CSF absorption at all intracranial pressures studied, and decreasing CSF formation at high pressures. This result is in accordance with evidence suggesting that impaired CSF absorption plays a major role in the pathogenesis of increased intracranial pressure in pseudotumor cerebri.

Assessment of cerebrospinal fluid compliance and outflow resistance: analysis of steady-state response to sinusoidal input

Cerebrospinal fluid dynamics have been studied in the past by analyses of responses to bolus, constant rate or constant pressure inputs. In this study, we present a method for analyzing CSF pressure responses to sinusoidal variation in the infusion rate. Infusion of artificial CSF into the cisterna magna of adult rats was modulated sinusoidally between 0 and 30 microliter/min. The resulting sinusoidal variation in intracranial pressure was recorded on a strip chart recorder simultaneously with the infusion rate signal. The two signals were analyzed for peak-to-peak variation, mean value, and phase shift for input frequencies in the range of 0.0015 to 0.01 HZ (0.00942 to 0.0628 radians/sec). The system was analyzed at each mean infusion rate as a parallel resistance and compliance with a first order linear model. The resistance to CSF outflow was determined as the change in mean steady-state pressure divided by the change in mean infusion rate. The compliance was then obtained from the frequency dependent phase shift between input and output using the first-order linear model. Resistance values were lower for higher average infusion rates consistent with our previous work, while compliance remained constant over the measured pressure range.

Saturable accumulation of the anionic herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D), by rabbit choroid plexus: early developmental origin and interaction with salicylates

Transport of the anionic herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D) was examined in vitro via the isolated choroid plexus of adult and neonatal rabbits and in vivo via ventriculocisternal perfusion. In vitro, the facilitated transport of 2,4-D by the choroid plexus was established in the rabbit by as early as 3 days of age. Uptake in both adults and neonates took place against a concentration gradient via a saturable process that was inhibited by ouabain and hypothermia (0 degrees C). Probenecid and hippuric acid were effective dose-dependent inhibitors of 2,4-D transport in vitro. The major metabolite of salicylate, salicyluric acid, was also an effective inhibitor, more than its precursor, salicylate, or gentisic acid, a second salicylate metabolite. Neither phenol, acetaminophen nor glycine inhibited 2,4-D transport. Thus, the effects appear specific for those compounds which share the organic acid transport system. The role of carrier-mediated transport in the clearance of 2,4-D from cerebrospinal fluid (CSF) was also evaluated in vivo by ventriculocisternal perfusion. Steady-state clearance of 2,4-D from CSF exceeded that of inulin and was reduced in a dose-dependent fashion in the presence of salicylate. Neither CSF formation nor absorption rates were changed. These results indicate that 2,4-D is transported from the CSF via the organic anion transport system, and that inhibitors of this transport system may block its elimination from the brain in vivo, just as they block its transport by the isolated choroid plexus.

Effect of increasing carbon chain length on organic acid transport by the choroid plexus: a potential factor in Reye's syndrome

Transport of the anionic herbicide 2,4-dichlorophenoxyacetic acid by choroid plexus is inhibited significantly by several short and medium chain acids. For both monocarboxylic and dicarboxylic homologs, inhibition clearly increases with chain length. It appears that organic acid compounds of longer chain length, higher brain uptake index, and highest inhibition of choroid plexus transport would be the ones producing the most significant increases in intracranial pressure in metabolic encephalopathy such as Reye's syndrome.

The effect of academic preparation on medical technologists' registry examination performance

This study investigated the effects of the college attended and the length of the educational program on ASCP Board of Registry Examination Scores. Registry scores were statistically analyzed for all graduates of Butterworth Hospital's (Grand Rapids, Michigan) Medical Technology program for the years 1970-80. Results indicated college differences in student academic preparation, as measured by the certification examination given by the ASCP Board of Registry. There were no statistical differences in average Registry examination scores for students who complete three versus four year educational programs. Other analyses considered sex differences in college grades and Registry exam performance, and the "grade inflation" phenomenon during the period of this study.

Phenytoin reversal and prevention of morphine-induced catalepsy in the rat

The interaction of morphine sulphate and phenytoin was studied with respect to morphine-induced catalepsy in the rat using a previously described method for measuring degree of immobility. As expected, catalepsy developed several minutes after intravenous morphine and lasted for more than ninety minutes. Intravenous phenytoin, 35 mg/kg, given fifteen min prior to or following the administration of morphine, 1 mg/kg, significantly prevented, or reversed, morphine-induced catalepsy. Control experiments revealed that the antagonistic effect was due solely to the morphine-phenytoin interaction. A similar effect was found with naloxone, 0.2 mg/kg. The data are discussed in terms of possible sites of interaction, including synaptosomal calcium metabolism.

Clearance of macromolecular and particulate substances from the cerebrospinal fluid system of the rat

Arachnoid villi in the intracranial dural sinuses constitute the principal sites for absorption of proteins and particulates from the cerebrospinal fluid (CSF) system. Although arachnoid villi in the rat are morphologically less complex than those found in other mammals, their resistance to CSF outflow, as assessed by a graded series of contstant flow manometric infusions, is similar to that found in other species. Moreover, inulin and polystyrene beads, when infused into the spinal subarachnoid space of rats, are rapidly cleared from the CSF system into intracranial dural sinuses. Inulin appeared in sinus blood 3 minutes after onset of infusion and reached concentrations 26 times greater than those found in the systemic circulation; particulate matter in the form of 0.5 micrometer polystyrene beads showed similar efflux characteristics. Hence, the CSF system of the rat is functionally similar to that found in other mammalian species, with arachnoid villi constituting a major efflux route for clearance of macromolecular and particulate substances.

Diazepam and dialysis encephalopathy

A patient with the clinical and electroencephalographic features of dialysis encephalopathy exhibited dramatic improvement with the initiation of diazepam therapy. Although improvement was sustained for a period of several weeks, her clinical condition eventually deteriorated despite continued treatment with diazepam and dialysis. Dialysis encephalopathy in this patient is compared with other cases recently reported in the medical literature as having a similar dramatic response to diazepam. It is concluded that diazepam transiently reverses a component of the dialysis encephalopathy syndrome, but it does not appear to change the ultimate prognosis for patients with this condition.

Inversion duplication of chromosome 6 with trisomic codominant expression of HLA antigens

Trisomic codominant expression of the HLA antigens was observed in an infant with duplication of a part of 6p occurring as a result of crossing over within a paternally transmitted pericentric inversion. The HLA-A and B loci were linked absolutely with the inversion chromosome in a four generation pedigree.

Aspirin prophylaxis in migraine

A prospective double-blind trial of aspirin prophylaxis demonstrated a reduction of more than 50% in headache frequency in 9 of 12 migraine patients. Response to aspirin did not correlate with age, duration of headache history, family history, or platelet ultrastructure. There is some evidence that response to aspirin is associated with raised platelet aggregation. This pilot study indicates that aspirin is effective in migraine prophylaxis.

Regulation of intracranial pressure in rat, dog, and man

Intracranial resistance and compliance were assessed in the cerebrospinal fluid system of rat, dog, and man by means of low-volume, short-duration infusions of artificial CSF into the subarachnoid space. A family of pressure/time response curves was obtained for each species: at low flow rates, steady-state pressure elevations were associated with normal neurological function; at high flow rates, rapid linear pressure elevations were associated with marked neurological dysfunction. From these curves a mathematical model was developed which describes transport and pressure-dependent valvelike characteristics of the CSF outflow resistance. This resistance shows a progressive phylogenetic change in rat, dog, and man which increasingly enhances the species' abilities to vent fluid from the intracranial cavity into the venous circulation. Arachnoid villi appear to be the major structures modulating sustained, nonlethal elevations of intracranial pressure.

Long-term administration of corticosteroids in myasthenia gravis

Favorable results were obtained in 30 patients with myasthenia gravis treated initially with high daily doses of prednisone and subsequently maintained on lower doses for a protracted period. In 45 incidents of treatment, complete remission occurred in 69 percent, marked improvement in 20 percent, and moderate improvement in 17 percent. Nineteen patients proceeded to thymectomy, with negligible morbidity and sustained improvement. In four patients, it was possible to discontinue prednisone 1 year or more after thymectomy.

Long-term prednisone followed by thymectomy in myasthenia gravis

The present series of thirty patients has led us to certain conclusions concerning the management and treatment of patients with myasthenia gravis. The use of cholinesterase inhibitors alone is reserved for those patients with purely ocular myasthenia whose deficits can be satisfactorily corrected with those agents. Some of those with ocular involvement may be disabled; and in light of our excellent results with that small group, as well as similar findings presented by Fischer et al., patients with disabling or refractory ocular myasthenia should be considered for treatment with prednisone. All other patients with myasthenia are given a course of oral corticosteroids (prednisone) initially at high doses, with subsequent tapering to maintenance, alternate-day low-dose therapy. Cholinesterase inhibitors are used as needed while the patient is receiving corticosteroids. We now anticipate that patients will exhibit sustained improvement within the first two weeks, reaching maximal improvement at about three months. Exacerbations of myasthenic weakness may occur in the early phases of treatment. Such exacerbations have been commonly mild and occur with a mean onset at 5 days, and have a mean duration of 6 days. Most patients have been able to tolerate an alternate-day schedule of prednisone therapy when maintenance levels were achieved. The effective maintenance dose has been determined as the smallest dose of prednisone which allows the patient to maintain maximal improvement. Following the establishment of maximal improvement, patients have been considered for thymectomy. In our experience, the sternum-splitting procedure has been tolerated extremely well by patients exhibiting marked imporvement or remission while on corticosteroids. In those patients where thymectomy is contraindicated, irradiation of the thymus might be considered. Patients are continued on maintenance steroid therapy following surgery for a period of time that has been arbitrary. Currently, we consider an attempt to discontinue steroids at approximately one year reasonable. Should the patient relapse after discontinuation of the medication, oral corticosteroid treatment is reinitiated. Consideration is given to the possibility of recurrent thymus in patients who repeatedly fail to maintain a remission when steroids have been stopped. Our experience has not permitted us to draw firm conclusions concerning how long a time high-dose daily steroid treatment should be continued in patients who show no favorable response to that therapy. Other modes of treatment, such as courses of parenteral ACTH, methyl prednisolone, dexamethazone, or antimetabolites might be considered if there is no response after 12 weeks of high-dose, daily corticosteroid therapy.

Minimizing loss of indoleacetic acid during purification of plant extracts

Published methods for isolation of 3-indoleacetic acid (IAA) were found to give low yields due to losses at specific steps. Loss during extraction was minimized by grinding tissue under a nitrogen atmosphere, using 0.02% sodium diethyldithiocarbamate in 80% ethanol as the extractant. When ethereal solutions of IAA were concentrated in vacuo, the hormone was lost, presumably by sublimation. This significant source of loss was eliminated by concentration at atmospheric pressure. Oxidative losses during application of extracts to chromatograms were reduced by prior application of an antioxidant to the origin of chromatograms. These precautions permitted development of a method where 10-50 μg of IAA could be recovered from soybean leaves with approximately 60% yield.