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Background and objectives: Tunneled cuffed hemodialysis catheters (TCC) get colonized by microorganisms, increasing risk for catheter related bacteremia (CRB). Our objective was to detect the prevalence of bacterial colonization of TCC by using quantitative PCR (qPCR) targeting 16S rRNA and by determining the intraluminal adherent biological material (ABM) coverage. Methods: A total of 45 TCC were investigated. The 16S rRNA qPCR technique was used to detect bacterial colonization after scraping the intraluminal ABM. Proximal, middle, and distal TCC were evaluated by scanning electron microscopy (SEM) to determine the percentage (%) of intraluminal ABM coverage. All catheters were cultured following sonication. Results: A total of 45 TCC were removed: 7 due to CRB, 3 for suspected CRB and 35 were removed for non-infectious etiologies. Bacterial colonization was detected in 27 TCC by documenting 16S rRNA qPCR (+) results (60%). Seven of these 16S rRNA qPCR (+) catheters were removed due to CRB. There was no difference in demographic, clinical, or laboratory values between the 16S rRNA (+) versus (−) TCC. The 16S rRNA qPCR (−) outcome was highly associated with CRB-free status with negative predictive value of 100%. Bacterial colonization was documented in 10 TCC using catheter cultures (22%), which was significantly less compared to qPCR method ( p = 0.0002). ABM were detected in all catheter pieces, with mean intraluminal surface coverage (ABMC) of 68.4 ± 26.1%. ABM was unlikely to be microbial biofilm in at least 36% of removed TCC as their 16S rRNA qPCR and catheter culture results were both negative. Conclusions: Detecting bacterial colonization of TCC was significantly higher with 16S rRNA qPCR compared to catheter cultures. The 16S rRNA qPCR (−) cannot be predicted and was strongly associated with absence of CRB. Intraluminal ABM was not associated with microbial presence in about 1/3 of the TCC. These pieces of evidence may help to improve prophylactic strategies against CRB.

The processing, storage, and flux of inorganic carbon in rivers and streams play an influential role in the lateral transfer of atmospheric and terrestrial carbon to the marine environment. Quantifying and understanding this transfer requires a rapid and accurate means of measuring representative concentrations of dissolved inorganic carbon (DIC) and CO(2) in field settings. This paper describes a field method for the determination of DIC based on the direct measurement of dissolved CO(2) using a commercial carbonation meter. A 100-mL water sample is combined with 10 mL of a high ionic strength, low-pH, citrate buffer, mixed well, and the dissolved CO(2) concentration is measured directly. The DIC is then calculated based on the dissolved CO(2) concentration, buffer-controlled ionic strength, pH, and temperature of the mixture. The method was accurate, precise, and comparable to standard laboratory analytical methods when tested using prepared sodium bicarbonate solutions up to 40 mM DIC, North Atlantic seawater, commercial bottled waters, and carbonate spring waters. Coal mine drainage waters were also tested and often contained higher DIC concentrations in the field than in subsequent laboratory measurements; the greatest discrepancy was for the high-CO(2) samples, suggesting that degassing occurred after sample collection. For chemically unstable waters and low-pH waters, such as those from high-CO(2) mine waters, the proposed field DIC method may enable the collection of DIC data that are more representative of natural settings.

Permanent vascular access (PVA) is preferred for long-term hemodialysis. Arteriovenous fistulae (AVF) have the best patency and the lowest complication rates compared to arteriovenous grafts (AVG) and tunneled cuffed catheters (TCC). However, AVF need time to mature. This study aimed to investigate predictors of time to first cannulation for AVF in pediatric hemodialysis patients. Data on first AVF and AVG of patients at 20 pediatric dialysis centers were collected retrospectively, including demographics, clinical information, dialysis markers, and surgical data. Statistical modeling was used to investigate predictors of outcome. First PVA was created in 117 children: 103 (88%) AVF and 14 (12%) AVG. Mean age at AVF creation was 15.0 ± 3.3 years. AVF successfully matured in 89 children (86.4%), and mean time to first cannulation was 3.6 ± 2.5 months. In a multivariable regression model, study center, age, duration of non-permanent vascular access (NPVA), and Kt/V at AVF creation predicted time to first cannulation, with study center as the strongest predictor (p < 0.01). Time to first cannulation decreased with increasing age (p = 0.03) and with increasing Kt/V (p = 0.01), and increased with duration of NPVA (p = 0.03). Secondary failure occurred in 10 AVF (11.8%). Time to first cannulation did not predict secondary failure (p = 0.29), but longer time to first cannulation tended towards longer secondary patency (p = 0.06). Study center is the strongest predictor of time to first cannulation for AVF and deserves further investigation. Time to first cannulation is significantly shorter in older children, with more efficient dialysis treatments, and increases with longer NPVA duration.

Conservation of wood turtles (Glyptemys insculpta) requires improved ecological knowledge near the southern extent of their geographic range. Our objectives were to determine home range sizes and structural habitat characteristics of wood turtles near the southern border of their geographic range in eastern West Virginia. We captured 284 wood turtles (137 males, 88 females, and 59 juveniles) along a 13.7-km reach of river from spring 2009 to summer 2011. Home ranges (95% minimum convex polygons) varied from 0.62 to 36.97 ha; male home ranges tended to be elongated along the river, whereas female and juvenile home ranges encompassed a greater proportion of terrestrial habitat. Low bare ground and rock cover and high vegetative vertical density were structural characteristics associated with the turtles' habitat compared with random plots. Our study provides vital data about home range, movements, and habitat use of wood turtles along the southern border of their range. These data will assist in pl...

Hemodialysis (HD) guidelines recommend permanent vascular access (PVA) in children unlikely to receive kidney transplant within 1 year of starting HD. We aimed to determine predictors of primary and secondary patency of PVA in pediatric HD patients. Retrospective chart reviews were performed for first PVAs in 20 participating centers. Variables collected included patient demographics, complications, interventions, and final outcome. There were 103 arterio-venous fistulae (AVF) and 14 AV grafts (AVG). AVF demonstrated superior primary (p = 0.0391) and secondary patency (p = 0.0227) compared to AVG. Primary failure occurred in 16 PVA (13.6%) and secondary failure in 14 PVA (12.2%). AVF were more likely to have primary failure (odds ratio (OR) = 2.10) and AVG had more secondary failure (OR = 3.33). No demographic, clinical, or laboratory variable predicted primary failure of PVA. Anatomical location of PVA was predictive of secondary failure, with radial having the lowest risk compared to brachial (OR = 12.425) or femoral PVA (OR = 118.618). Intervention-free survival was predictive of secondary patency for all PVA (p = 0.0252) and directly correlated with overall survival of AVF (p = 0.0197) but not AVG. Study center demonstrated statistically significant effect only on intervention-free AVF survival (p = 0.0082), but not number of complications or interventions, or outcomes. In this multi-center pediatric HD cohort, AVF demonstrated primary and secondary patency advantages over AVG. Radial PVA was least likely to develop secondary failure. Intervention-free survival was the only predictor of secondary patency for AVF and directly correlated with overall access survival. The study center effect on intervention-free survival of AVF deserves further investigation.

We examine how climate and irrigation conditions are associated with malaria infection from 1986 to 1995 in two climatically dissimilar regions in India. We analyze annually averaged malaria parasite incidence (API) and seasonally averaged climate and irrigation variables in western Rajasthan and Arunachal Pradesh. In arid western Rajasthan, API is significantly positively correlated with summer precipitation and soil moisture, and negatively correlated with summer potential evapotranspiration. Irrigation variables during boreal spring show a significant positive correlation with API in the moisture-limited region. In humid Arunachal Pradesh, API is positively related to summer temperature, but negatively related to summer precipitation and spring irrigation variables, while no statistically significant correlations are observed. During the years of high sea surface temperatures (SSTs) in the tropical western Pacific, increasing precipitation (accompanied by decreasing temperature) in northwestern India appears to promote malaria infection in arid western Rajasthan. However, during the same years, decreasing precipitation and increasing temperature result in increasing malaria incidence in humid Arunachal Pradesh. The statistically significant relationships of climate and irrigation factors with API in western Rajasthan suggest that increasing spring irrigation activity and wetter summer climates related to warmer SST in tropical western Pacific could increase malaria risk in the arid climate region.

Background and Purpose: Develop and assess psychometric properties of the Wang Pregnancy Stress Scale for measuring stress among pregnant women in Taiwan. Methods: Data were collected in 3 obstetric and gynecological clinics in Taiwan; 485 pregnant women participated in this study. We used exploratory factor analysis and internal consistency reliability was measured using Cronbach's alpha. Results: A 4-factor structure emerged for the Wang Pregnancy Stress Scale. The internal reliability of the scale as measured by Cronbach's alpha was .898, with standardized alpha .905. Conclusions: The Wang Pregnancy Stress Scale has high reliability and validity in measuring pregnancy stress that would allow nurses or health care workers to measure women's stress levels during pregnancy. Nurses can use the assessed pregnancy stress to alter intervention of care for their pregnant clients.Keywords: pregnancy stress; scale development; reliability; validity; factor analysis; Taiwanese womenFew cross-cultural, reliable, and valid scales are available for measuring stress in pregnant women, with the exception of Chen's (Chen, Chen, & Huang, 1989) initial study of Taiwanese pregnant women in 1989. Chen's instrument, however, does not address socioeconomic aspects of pregnancy stress. The purpose of this research was to develop and assess psychometric properties of the Wang Pregnancy Stress Scale for measuring stress among pregnant women in Taiwan. The Wang Pregnancy Stress Scale includes items that address some socioeconomic aspects of pregnancy stress. Understanding pregnancy-related stressors is important for developing intervention programs that would help to facilitate nursing care of pregnant women among diverse cultural groups.BACKGROUND AND CONCEPTUAL FRAMEWORKFor many expectant mothers, pregnancy can be a stressful time. Some women experience very high levels of stress, whereas others see pregnancy as a welcome challenge. For pregnant women, loss of a job, divorce, or death of a family member can contribute to high levels of stress during pregnancy. Potential problems during pregnancy can include fetal development, learning and attention deficiency, anxiety, and depressive symptoms (North Dakota Pregnancy Risk Assessment Monitoring Systems, 2000).Depression during pregnancy can be associated with poor maternal self-care behaviors, which may influence the baby's health, and may place the mother at significant risk of developing postpartum depression (Dennis, Ross, & Grigoriadis, 2007). Studies have also indicated that high stress and mood disturbances during pregnancy are related to various negative maternal and birth outcomes (Flynn, Blow, & Marcus, 2006; Kinney, Munir, Crowley, & Miller, 2008; Marcus, Flynn, Blow, & Barry, 2003). Prenatal psychosocial stress is common, and high levels of stress are associated with negative maternal factors, such as alcohol consumption, drug usage, smoking, and depression, among other factors, known to contribute to poor pregnancy outcomes (Woods, Melville, Guo, Fan, & Gavin, 2010). Prenatal exposure to stressful life events is associated with significantly increased risk of autism disorder as well as other disorders, such as schizophrenia and depression (Kinney et al., 2008). Social support has been found to be important to postpartum women in adaptation to a new role, in helping new mothers to be more responsive to their babies, and in facilitating their intimate relationships (Baker & Taylor, 1997). Social support has an indirect effect on women's health after childbirth (Hung, 2007). Hung identified concerns about role attainment, concerns about negative body image, and concerns about lack of social support as postpartum stressors. Mothers' behaviors are influenced by their perception of the amount of positive support they have received (Henshaw, 2003).Asian women have less postpartum depression because of traditional postpartum rituals (Stern & Krukman, 1983). …

The original version of this article unfortunately contained a mistake. The name of Vimal Chadha was presented incorrectly. The corrected author list is given above.

This prospective cohort study determined the type, frequency, intensity, and duration of actual vs expected leisure activity among a cohort undergoing total knee arthroplasty. Data on actual and expected participation in 36 leisure activities were collected preoperatively and at 12 months in 90 patients with knee osteoarthritis. Despite high expectations, there were statistically and clinically significant differences between actual and expected activity at 12 months suggesting that expectations may not have been fulfilled. The differences were equivalent to walking 14 less miles per week than expected, which is more than the amount of activity recommended in national physical activity guidelines. Perhaps an educational intervention could be implemented to help patients establish appropriate and realistic leisure activity expectations before surgery.

There are current concerns that antibiotic lock solutions (ABL) can induce antimicrobial resistance in long-term hemodialysis patients. Retrospective chart review of 157 children on hemodialysis between January 1997 and June 2006 was performed. In ERA I, only systemic antibiotics were used. In ERA II, ABL were added to systemic antibiotics when needed. In ERA III, ABL were used for treatment of all cases of catheter-related bacteremia (CRB) and for CRB prophylaxis in high-risk patients. The study includes 111,325 catheter days. The CRB incidence was 3.9 CRB/1000 catheter days. There was significant decrease for the total systemic antibiotic exposure (P = 0.0484) and the percentage of catheters lost to malfunction (P = 0.001) in ERA III. Protocol ABL exposure was associated with a trend to increased tobramycin-gentamicin resistance for gram-positive CRBs (P = 0.2586) but with improved tobramycin-gentamicin resistance for gram-negative (P = 0.0949) and polymicrobial CRBs (P = 0.1776) and improved vancomycin resistance for gram-positive CRBs (P = 0.0985). This retrospective analysis does not support the premise that ABL use will promote antimicrobial resistance in the hemodialysis population. The decreased exposure to systemic antibiotics by vigorous ABL use may even improve the antimicrobial resistance patterns in this population in the long term.

This study determined the prevalence of complications related to early weight bearing and the factors associated with time to healing in children after a complete tibial shaft fracture. Radiographs and medical records were reviewed from patients with unilateral, closed, complete tibial shaft fractures who were treated nonoperatively with a long leg cast. There were 55 males (68.8%) and 25 females (31.2%) with a mean ± SD age of 6.0 ± 4.0 years (range 1-16). There were few complications (2.5%) and patients healed faster if they bore weight earlier (0.3 days faster for each day earlier to weight bearing, P = 0.02), were younger (2.3 days faster per year younger, P < 0.001), were female (2.7 days faster than males, P = 0.02), or did not have a closed reduction (3.8 days faster, P = 0.002) (R = 0.63). Time to weight bearing after complete tibial shaft fracture was not associated with an increased risk of complications. Earlier weight bearing was associated with a shorter time to healing. This study provides support for treatment with early weight bearing in children with closed, complete tibial shaft fractures.

The aim of this retrospective study was to investigate if the application of chlorhexidine-based solutions (ChloraPrep®) to the exit site and the hub of long-term hemodialysis catheters could prevent catheter-related bacteremia (CRB) and prolong catheter survival when compared with povidone–iodine solutions. There were 20,784 catheter days observed. Povidone–iodine solutions (Betadine®) were used in the first half of the study and ChloraPrep® was used in the second half for all the patients. Both groups received chlorhexidine-impregnated dressings at the exit sites. The use of Chloraprep® significantly decreased the incidence of CRB (1.0 vs 2.2/1,000 catheter days, respectively, P = 0.0415), and hospitalization due to CRB (1.8 days vs 4.1 days/1,000 catheter days, respectively, P = 0.0416). The incidence of exit site infection was similar for the two groups. Both the period of overall catheter survival (207.6 days vs 161.1 days, P = 0.0535) and that of infection-free catheter survival (122.0 days vs 106.9 days, P = 0.1100) tended to be longer for the catheters cleansed with ChloraPrep®, with no statistical significance. In conclusion, chlorhexidine-based solutions are more effective for the prevention of CRB than povidone–iodine solutions. This positive impact cannot be explained by decreased number of exit site infections. This study supports the notion that the catheter hub is the entry site for CRB.

This retrospective study was designed to investigate the effectiveness of tissue plasminogen activator-tobramycin antibiotic lock solutions (TPA/tobra ABLs) for prophylaxis of catheter-related bacteremia (CRB) in high-risk children on long-term hemodialysis. During the first 6 months (Era 1), the high-risk group was defined. These patients received TPA/tobra ABL prophylaxis after every hemodialysis treatment for the next 6 months (Era 2). The prophylaxis regimen was applied once a week for the third 6-months period (Era 3). Primary endpoints were CRB and infection-free catheter survival. There were 16,412 catheter days, and 95 cases of CRB in 43 children. The incidence of CRB was 5.8/1,000 catheter days. Significant decrease in the incidence of CRB was observed when prophylactic TPA/tobra ABL was used in the high-risk group (P = 0.0201). There was a tendency for less CRB when prophylactic ABL was applied after every hemodialysis session compared with once a week (P = 0.0947). The catheters in the high-risk group had shorter survival times than those in the average-risk group in Era 1 (P < 0.0001). However, both the overall and infection-free survival of the catheters in the high-risk group significantly improved while the patients were receiving TPA/tobra ABL prophylaxis, becoming similar to the outcomes of the catheters in the average-risk group and exhibiting statistically non-significant differences (P = 0.5571 and P = 0.9711, respectively). In conclusion, the TPA/tobra ABLs may effectively reduce the rate of CRB, and this may prolong both the overall and infection-free survival times of the catheters in the high-risk group.

Background and objectives: This retrospective study compared the effectiveness of the timing of the antibiotic locks to clear catheter-related bacteremia in children on chronic hemodialysis. Design, setting, participants, & measurements: The early antibiotic lock group received antibiotic locks along with systemic antibiotics from the very beginning of catheter-related bacteremia. The late antibiotic lock group was given only systemic antibiotics initially, and antibiotic locks were used late in the infection if the catheter-related bacteremia could not be cleared after resolution of symptoms. Results: There were 264 catheter-related bacteremias in 79 children during 6 yr of observation. Early antibiotic locks were able to clear catheter-related bacteremia and resolve the symptoms more effectively without the need for catheter exchange when compared with late antibiotic locks. A total of 84 catheter-related bacteremias required wire-guided exchange of the catheters. Late antibiotic locks required wire-guided catheter exchange more frequently than the early antibiotic locks. The post–catheter-related bacteremia infection–free survival of the catheters after wire-guided exchange were significantly longer than those of both antibiotic lock groups. Recurrence of catheter-related bacteremia within 45 d after wire-guided exchange occurred at similar rates compared with the antibiotic lock groups. Conclusion: Antibiotic locks are significantly more effective in clearing catheter-related bacteremia when used early in infection, diminishing the need for catheter exchange. Wire-guided exchange has a late-onset advantage for infection-free survival compared with catheter in situ treatment. The recurrence rates in the first 45 d after catheter-related bacteremia are similar regardless of the treatment strategy.

Food availability influences movements, population dynamics, and harvest of black bears (Ursus americanus) in the Appalachian Mountains. We compared combinations of hard and soft mast indices to black bear non-hunting mortalities in West Virginia, USA, 1980–2004. Mast conditions were inversely related to non-hunting black bear mortalities. We constructed regression equations to predict non-hunting bear mortalities and used Akaike's Information Criterion (AIC) to compare fit of each model to the data. Oak (Quercus spp.; ΔAICc = 0.000), oak + hickory (Carya spp.; ΔAICc = 0.251), all hard mast (ΔAICc = 6.41), and hard mast + black cherry (Prunus serotina; ΔAICc = 7.06) were considered the best competing models for explaining non-hunting black bear mortalities. Managers may use this data to help explain and predict the importance of hard mast conditions on non-hunting black bear mortalities.

The processing, storage, and flux of inorganic carbon in rivers and streams play an influential role in the lateral transfer of atmospheric and terrestrial carbon to the marine environment. Quantifying and understanding this transfer requires a rapid and accurate means of measuring representative concentrations of dissolved inorganic carbon (DIC) and CO2 in field settings. This paper describes a field method for the determination of DIC based on the direct measurement of dissolved CO2 using a commercial carbonation meter. A 100-mL water sample is combined with 10 mL of a high ionic strength, low-pH, citrate buffer, mixed well, and the dissolved CO2 concentration is measured directly. The DIC is then calculated based on the dissolved CO2 concentration, buffer-controlled ionic strength, pH, and temperature of the mixture. The method was accurate, precise, and comparable to standard laboratory analytical methods when tested using prepared sodium bicarbonate solutions up to 40 mM DIC, North Atlantic seawater, commercial bottled waters, and carbonate spring waters. Coal mine drainage waters were also tested and often contained higher DIC concentrations in the field than in subsequent laboratory measurements; the greatest discrepancy was for the high-CO2 samples, suggesting that degassing occurred after sample collection. For chemically unstable waters and low-pH waters, such as those from high-CO2 mine waters, the proposed field DIC method may enable the collection of DIC data that are more representative of natural settings.

Systemic imidacloprid is the most widely used insecticide to control the hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), an exotic pest of eastern hemlock, Tsuga canadensis (L.) Carriere in the United States. This study was conducted to 1) determine the effect of treatment timing (spring vs. fall) and application method (trunk injection vs. soil injection) on the spatial and temporal distribution of imidacloprid within the crown of A. tsugae-free eastern hemlock using a competitive enzyme-linked immunosorbent assay (ELISA), 2) compare ELISA to gas chromatography-mass spectrometry (GC/MS) for the detection of imidacloprid in xylem fluid, and 3) determine the concentration of imidacloprid in leaf tissue using high performance liquid chromatography with tandem mass spectrometric (LC/MS/MS) detection methods. Xylem fluid concentrations of imidacloprid were found to be significantly higher for spring applications than for fall applications and for trunk injections than soil injections in the first year posttreatment. A total of 69% of samples analyzed by ELISA gave 1.8 times higher concentrations of imidacloprid than those found by GC/MS, leading to evidence of a matrix effect and overestimation of imidacloprid in xylem fluid by ELISA. A comparison of the presence of imidacloprid with xylem fluid and in leaf tissue on the same branch showed significant differences, suggesting that imidacloprid moved intermittently within the crown of eastern hemlock.

Background. Antibiotic lock (ABL) solutions can effectively treat catheter-related bacteraemia (CRB) without the need for catheter exchange. This approach does not increase secondary infectious complications. We evaluated the risk factors that contribute to failure when CRB is treated with ABLs and systemic antibiotics in paediatric haemodialysis patients. Methods. A retrospective chart review of 72 children on haemodialysis between January 2004 and June 2006 was performed. We evaluated risk factors for ABL treatment using patients' characteristics, CRB/catheter characteristics and patients' biochemical profiles. The first CRB of each catheter was included in the statistical analysis. Our end points were outcome at 2 weeks of treatment and at 6 weeks following treatment. Compound symmetry covariance structure was employed for statistical analysis. Results. We treated 149 CRB in 50 patients. The incidence was 3.4 CRB/1000 catheter days. Thirty CRB failed to be cleared with the use of ABL and systemic antibiotics at 2 weeks of treatment (30/149, 20 vs 80%, P < 0.001). Twenty-four of these catheters required exchange. Thirty-nine of the treated catheters got re-infected within the next 6 weeks (39/125, 31 vs 69%, P < 0.001). CRB aetiology was the only statistically significant independent variable for 2-week outcome (P = 0.033). Coagulase-negative Staphylococcus CRB had higher odds of being cleared at 2 weeks compared with other CRB aetiologies. For the 6-week outcome, the statistically significant independent variables in the final model included age (P = 0.048) and serum phosphorous level (P < 0.001). Younger age and higher serum phosphorous levels were independent risk factors for failure at 6 weeks with re-infection. Area under the receiver operating characteristic (ROC) curve for the model of the 2-week outcome was 0.736 with the percentage of correct predictions at 81.2%. Area under the ROC curve for the model of the 6-week outcome was 0.689 with the percentage of correct predictions at 75.5%. Conclusions. CRB can effectively be treated with ABLs and systemic antibiotics. CRB aetiology is the only independent variable of early treatment failure. Younger age and higher serum phosphorous levels are independent risk factors for re-infection at 6 weeks.

Twenty-seven patients with acute neurosurgical injuries were compared with 23 patients with neurosurgical and multisystem injuries and 10 patients with multi-system injuries without neurosurgical injuries. Patients with isolated acute neurosurgical injuries did not demonstrate a hypermetabolic state with increased loss of nitrogen and decreased circulating levels of albumin, prealbumin, and retinol-binding protein when compared to multisystem-injured patients. Patients with demonstrated hypermetabolism on day 1 were supported with parenteral nutrition which decreased their protein losses and stabilized other metabolic variables such as calcium and phosphorus. It is concluded that patients with neurosurgical and other multisystem injuries require close metabolic monitoring. Early institution of metabolic support in hypercatabolic patients may prevent clinically significant depletion states.

To the Editor. —We read with interest the article "Complications of Metrizamide Myelography" by Killebrew et al (Archives1983;40:78-80). The group of neurosurgeons with whom we are associated perform approximately 40 myelograms per month, of which a growing segment are cervical metrizamide myelograms. We would like to share some of our treatment protocol that has brought our complication rate for lumbar myelography to less than 5% and that for cervical myelography to less than 15%. Standard metrizamide, in concentrations of 18 mL of 180 mg/dL for lumbar studies and 10 mL of 260 mg/ dL for cervical and complete myelographic studies, are used. All patients have nothing by mouth on the morning of myelographic examination. Preoperative medications given intramuscularly one hour prior to the procedure consist of 10 mg of diazepam, 100 mg of hydroxyzine hydrochloride, and 4 mg of dexamethasone sodium phosphate. Following myelography, the patient is placed in