Habitat requirements affect genetic variation in three species of mayfly (Ephemeroptera, Baetidae) from South Africa

This study investigates genetic diversity in three species of Ephemeroptera, one eurytopic and therefore widespread (Afroptilumsudafricanum) and two stenotopic and thus endemic (Demoreptusnatalensis and Demoreptuscapensis) species, all of which co-occur in the southern Great Escarpment, South Africa. Mitochondrial DNA was analysed to compare the genetic diversity between the habitat generalist and the two habitat specialists. Afroptilumsudafricanum showed no indication of population genetic structure due to geographic location, while both Demoreptus species revealed clear genetic differentiation between geographic localities and catchments, evident from phylogenetic analyses and high F_ST values from AMOVA. In addition, the phylogenetic analyses indicate some deeper haplotype divergences within A.sudafricanum and Demoreptus that merit taxonomic attention. These results give important insight into evolutionary processes occurring through habitat specialisation and population isolation. Further research and sampling across a wider geographic setting that includes both major mountain blocks of the Escarpment and lowland non-Escarpment sites will allow for refined understanding of biodiversity and associated habitat preferences, and illuminate comparative inferences into gene flow and cryptic speciation.

Multimodal analgesia using intrathecal diamorphine, and paravertebral and rectus sheath catheters are as effective as thoracic epidural for analgesia post-open two-phase esophagectomy within an enhanced recovery program

Thoracic epidural (TE) analgesia has been the standard of care for transthoracic esophagectomy patients since the 1990s. Multimodal anesthesia using intrathecal diamorphine, local anesthetic infusion catheters (LAC) into the paravertebral space and rectus sheaths and intravenous opioid postoperatively represent an alternative option for postoperative analgesia. While TE can provide excellent pain control, it may inhibit early postoperative recovery by causing hypotension and reducing mobilization. The aim of this study is to determine whether multimodal analgesia with LAC was effective with respect to adequate pain management, and compare its impact on hypotension and mobility. Patients receiving multimodal LAC analgesia were matched using propensity score matching to patients undergoing two-phase trans-thoracic esophagectomy with a TE over a two-year period (from January 2015 to December 2016). Postoperative endpoints that had been evaluated prospectively, including pain scores on movement and at rest, inotrope or vasoconstrictor requirements, and hypotension (systolic BP < 90 mmHg), were compared between cohorts. Out of 14 patients (13 male) that received LAC were matched to a cohort of 14 patients on age, sex, and comorbidity. Mean and maximum pain scores at rest and movement on postoperative days 0 to 3 were equivalent between the groups. In both cohorts, 50% of patients had a pain score of more than 7 on at least one occasion. Fewer patients in the LAC group required vasoconstrictor infusion (LAC: 36% vs. TE: 57%, P = 0.256) to maintain blood pressure or had episodes of hypotension (LAC: 43% vs. TE: 79%, P = 0.05). The LAC group was more able to ambulate on the first postoperative day (LAC: 64% vs. TE: 43%, P = 0.14) but these differences were not statistically significant. Within the epidural cohort, three patients had interruption of epidural due to dislodgement or failure of block compared to no disruption in the multimodal local anesthesia catheters group (P = 0.05). Therefore, multimodal anesthesia using spinal diamorphine with combined paravertebral and rectus sheath local anesthetic catheters appears to provide comparable pain relief post two-phase esophagectomy and may provide more reliable and safe analgesia than the current standard of care.

Professional behaviours demonstrated by undergraduate dental students using an incident reporting system

Critical incident reporting is widely used across healthcare and other sectors for reporting adverse events or behaviours. More recently it has been used in medical education as a means of assessing student professionalism. The aims of this study were to determine the usage of critical incident forms when reporting behaviours related to professionalism demonstrated by undergraduate dental students, and the types of behaviours exhibited. Three types of form could be awarded for highly professional (green), minor unprofessional (yellow) and serious unprofessional (red) behaviours. All forms completed over a two-year period were analysed recording the year of student, type of card and demographic of the member of staff reporting the incident. All text relating to the nature of the incident was entered into a qualitative data analysis software package and analysed thematically. In total, 583 cards were awarded, 55% green, 34% yellow and 11% red. Seventy-four percent of cards were awarded in a clinical environment, with administrative staff using them the most (29%). The overwhelming professional behaviours demonstrated related to altruism. The most common unprofessional behaviours related to a lack of conscientiousness, although a greater range of common unprofessional behaviours were reported. In conclusion, critical incidents forms were widely used for reporting both professional and unprofessional behaviours particularly in clinical environments by a range of staff. Such forms may be a valuable addition to the professionalism assessment portfolio, capturing behaviours not previously reported using traditional methods.

A comparison of grades awarded by peer assessment, faculty and a digital scanning device in a pre-clinical operative skills course

OBJECTIVE

The aim of this study was to compare the grades awarded by two experienced assessors with peer-assessment marks and measurements from a digital scanning device (Prepassistant; KaVo, Biberach, Germany), for full gold crown preparations completed in a pre-clinical operative skills course on typodont teeth.

METHODS

Seventy-eight preparations on typodont teeth were randomised and assessed by all three methods. Agreement was measured using weighted kappa statistics, and mean rank scores given by the Friedman test.

RESULTS

The highest agreement was seen between the experienced assessors (0.38), closely followed by peer assessment and experienced assessor agreement (0.36, 0.29). Despite this, the results indicate poor levels of agreement. No agreement was seen between any of the assessment methods when compared to the digital scanning device.

CONCLUSIONS

The findings of this study could be related to the difficulty of calculating a single grade from the output of the device, in addition to the inability of the machine to assess all the factors necessary for an acceptable preparation. From this study, it can be concluded that this device is not suitable for calculating grades when used in isolation. Further research could explore the role of the Prepassistant in providing student feedback, its potential to enhance the learning experience and the subsequent effect on performance.

Early mental health morbidity and later smoking at age 17 years

BACKGROUND

We examined the relationship between the onset and pattern of childhood mental health disorders and subsequent current smoking status at age 17 years.

METHOD

Data were from a prospective cohort study of 2868 births of which 1064 supplied information about their current smoking at 17 years of age. The association between the onset and pattern of clinically significant mental health disorders in the child and subsequent smoking at age 17 years was estimated via multivariable logistic regression.

RESULTS

Relative to 17 year olds who never had an externalizing disorder, 17-year-olds who had an externalizing disorder at age 5, 8 or 14 years were, respectively, 2.0 times [95% confidence interval (CI) 1.24-3.25], 1.9 (95% CI 1.00-3.65) or 3.9 times (95% CI 1.73-8.72) more likely to be a current smoker. Children with an ongoing pattern of externalizing disorder were 3.0 times (95% CI 1.89-4.84) more likely to be smokers at the age of 17 years and those whose mothers reported daily consumption of 6-10 cigarettes at 18 weeks' gestation were 2.5 times (OR 2.46, 95% CI 1.26-4.83) more likely to report smoking at 17 years of age. Associations with early anxiety and depression in the child were not found.

CONCLUSIONS

Current smoking in 17-year-olds may be underpinned by early emergent, and then, ongoing, externalizing disorder that commenced as young as age 5 years as well as exposure to early prenatal maternal smoking. The associations documented in adults and adolescents that link tobacco smoking and mental health are likely to be in play at these early points in development.

Successful reversal of threatening carotid artery occlusion in HIV-associated non-aneurysmal vasculitis

We report a case of HIV-associated carotid vasculitis, causing cerebral infarction. Immediate corticosteroid treatment was followed by improvement, with radiological documentation of reversal of the vasculitic changes, preventing arterial occlusion. Vasculitis should be considered as a diagnosis in stroke in HIV and steroid treatment considered as a potentially life-saving intervention.

A case of severe eczema following use of imiquimod 5% cream

Imiquimod 5% cream, an immune response modifier licensed for treatment of external ano-genital warts and superficial basal cell carcinomata, is known to cause local erythema, oedema and, rarely, exacerbation of psoriasis. We describe a case of exacerbation of eczema following application of this cream in a man with penile warts.

cDNA cloning of the polymeric immunoglobulin receptor of the marsupial Macropus eugenii (tammar wallaby)

cDNA encoding a marsupial polymeric immunoglobulin receptor (pIgR) was isolated from Macropus eugenii (tammar wallaby) mammary lymph node primarily by reverse transcriptase coupled polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) PCR. This resulted in a 5' truncated clone and, in order to obtain the full-length sequence, genomic walking PCR was utilized. The complete sequence consists of 2696 bp of cDNA and encodes a predicted polypeptide of 732 amino acids. The wallaby sequence is highly conserved in relation to the only other reported marsupial pIgR sequence, that of Trichosurus vulpecula (brushtail possum), having a nucleotide identity of 86.7% and a deduced amino acid identity of 79.9%. The wallaby nucleotide sequence also has a moderate degree of similarity with the pIgR sequences of eutherian mammals, being most similar to that of the rat, with an identity of 63.1%. At the amino acid level, in comparison to eutherian sequences, the wallaby pIgR is most similar to that of humans with an identity of 52.6%. pIgR phylogenetic trees were constructed for tammar wallaby, brushtail possum and several eutherian mammal cDNA and deduced amino acid sequences. In both DNA and protein analyses, the eutherian sequences formed a sister clade to the exclusion of the marsupial sequences, in agreement with the current view of mammalian evolution.

c-Myc initiates illegitimate replication of the ribonucleotide reductase R2 gene

The mechanisms through which the oncoprotein c-Myc initiates locus-specific gene amplification are not understood. When analysing the initiation mechanism of c-Myc-dependent amplification of the mouse ribonucleotide reductase R2 (R2) gene, we observe c-Myc-dependent initiation of illegitimate DNA replication of the R2 gene. We demonstrate multiple simultaneous c-Myc-induced R2 replication forks, whereas R2 normally replicates with a single fork. In contrast, cyclin C replicates with only a single replication fork irrespective of c-Myc deregulation. In addition to de novo replication forks, c-Myc also initiates bi-allelic replication of R2, abrogating its normal mono-allelic replication pattern. Moreover, several chromosomal regions also display c-Myc-induced illegitimate replication profiles. Thus, c-Myc can act as an illegitimate replication-licensing factor that promotes de novo replication initiation and illegitimate replication timing that adversely impacts upon genomic stability.

Nonoxynol-9 causes rapid exfoliation of sheets of rectal epithelium

Nonoxynol-9 (N-9) containing spermicides and other N-9 containing products are commonly used as lubricants during rectal intercourse. We have previously demonstrated that rectal application of N-9 products in mice can cause exfoliation of epithelial cells, increasing the probability of infection by HSV-2. To determine if N-9-containing products would have a similar effect on the rectal epithelium in humans, the application of K-Y Plus and ForPlay, both over-the-counter (OTC) N-9 products, were compared to the application of two formulations, carrageenan and methyl cellulose, that do not contain N-9. The effects of each formulation were evaluated in 4 human participants. Light and electron microscope examination of rectal lavage specimens collected 15 min post application of N-9 products revealed the presence of sheets of epithelium. Each sheet contained hundreds of epithelial cells that included columnar and goblet cells, varieties of cells typical of rectal epithelial morphology. Sheets of epithelium were not observed in rectal lavage specimens collected 8 to 12 hr post N-9 product use or in either of the timed lavages involving non-N-9 containing formulations. In addition, no sheets of epithelial cells were observed in the baseline lavage specimens. We conclude that the rectal use of N-9-containing products causes a rapid exfoliation of extensive areas of the rectal epithelium. Exfoliation of the epithelium is no longer observed at 8 hr. It is reasonable to assume that the loss of the protective epithelium would render a person more at risk for infection by HIV and other sexually transmitted pathogens. We, therefore, caution against the use of N-9-containing products during rectal intercourse.

FE(NO): relationship to exhalation rates and online versus bag collection in healthy adolescents

Measurement of exhaled nitric oxide (FE(NO)) is a noninvasive and practical method for assessing airway inflammation. We conducted this investigation to determine the most appropriate flow rate for FE(NO) measurement and to obtain normal values for FE(NO). We determined which expiratory flow was easy to sustain, generated reproducible values, and provided good correlation between offline and online measurements. Thirty-two healthy subjects (15- 18 yr old) underwent spirometry and FE(NO) measurements, using a chemiluminescent NO analyzer at expiratory flow rates of 46, 31, 23, 15, 10, 7, 5, and 4 ml/s. The major findings were as follows: (1) FE(NO) increased as flow rates decreased, with strong correlation between FE(NO) values and flow rates at the four highest flows (0. 85- 0.93, p < 0.001); (2) there were no significant differences and good agreement between offline bag and online FE(NO) values for the four highest flows (p < 0.09-0.83); (3) online FE(NO) values increased with age 15-17 yr at all flow rates, but decreased at age 18 yr; and (4) using multiple regression, significant predictors of FE(NO) were flow, body surface area, age, and FEF(25-75). On the basis of these results, we provide FE(NO) values for healthy adolescents and propose that the ideal flow rate for children is between 30 and 50 ml/s.

Screening for hearing loss and middle-ear disorders in children using TEOAEs

The purpose of this research was to obtain the sensitivity and specificity of transient evoked otoacoustic emission (TEOAE) screening procedures compared with conventional audiometric pure-tone screening and tympanometry. Pass/refer values were obtained from a group of 297 ears of 152 preschool and school-aged children, 3 to 8 years of age. The sensitivity and specificity of the TEOAE screenings compared with the pure-tone screenings were 81% and 95%, respectively. The sensitivity and specificity of TEOAE screenings compared with tympanometric screenings were 60% and 91%, respectively.

Emergency management of ischemic stroke

The accurate diagnosis of acute ischemic stroke is possible using clinical skills and diagnostic tools that are familiar to all neurosurgeons. Avoidance of immediate complications relies on the fundamentals of critical care. Effective treatment for ischemic stroke is available in the form of intravenous thrombolysis, but many stroke patients are denied this therapy because of the narrow window of opportunity for safe administration. Intra-arterial delivery may extend this benefit to a greater number of patients and may eventually prove more effective than intravenous treatment. Surgical treatment in a small number of ischemic stroke patients can be lifesaving and may afford reasonable functional recovery. This article discusses typical clinical presentations and differential diagnosis, diagnostic imaging for ischemic stroke, and possible treatments.

Impairment of cingulothalamic learning-related neuronal coding in rabbits exposed to cocaine in utero: general and sex-specific effects

Neuronal activity was recorded in the cingulate cortex and the limbic thalamus in Dutch-belted rabbits (Oryctolagus cuniculus) exposed to cocaine (8 mg/kg/day i.v.) or saline in utero during acquisition and reversal learning of a discriminative avoidance response. Anterior cingulate cortical excitatory training-induced activity (TIA) was attenuated in cocaine-exposed female rabbits during acquisition and reversal learning, but only during reversal learning in male rabbits. Posterior cingulate cortical excitatory TIA was lessened in cocaine-exposed rabbits during acquisition, whereas discrimination between the positive and negative cues was enhanced. Neuronal firing was attenuated in the anterior ventral thalamus in cocaine-exposed rabbits during acquisition and reversal learning. Behavioral learning was normal in cocaine-exposed rabbits. Other data suggest that rabbits exposed to cocaine in utero exhibit a learning deficit when trained with nonsalient cues.

Rebound intracranial hypertension in dogs after resuscitation with hypertonic solutions from hemorrhagic shock accompanied by an intracranial mass lesion

We compared intracranial pressure (ICP) and cerebral blood flow (CBF) in dogs after inflating a subdural intracranial balloon to increase ICP to 20 mm Hg, inducing hemorrhagic shock (mean arterial pressure [MAP] of 55 mm Hg), and infusing a single bolus of fluid consisting of either 54 mL/kg of 0.8% saline (SAL), 6 mL/kg of 7.2% hypertonic saline (HS), 20% hydroxyethyl starch (HES) in 0.8% SAL, or a combination fluid (HS/HES) containing 20% HES in 7.2% saline. Twenty-six dogs were ventilated with 0.5% halothane in N2O and O2 (60:40 ratio). As ICP was maintained at 20 mm Hg, rapid hemorrhage reduced MAP to 55 mm Hg (time interval of zero [T0]) which was maintained at that level for 30 minutes (until T30). Subsequently, over a 5-minute interval (T30-T35), one of the four randomly assigned resuscitation fluids was infused. Data were collected at baseline; after subdural balloon inflation; at T0, T30, T35, and 30-minute intervals thereafter for 2 hours (T65, T95, T125, and T155). CBF and ICP were compared using repeat-measure ANOVA. Cerebral blood flow was greater at T35 in the HS and HS/HES groups than in the HES group (P = .025). In the SAL group, ICP increased significantly from T0 to T35, remaining unchanged thereafter. At T35, ICP in the HS group was significantly lower than in the SAL group (P < .05) but subsequently increased. ICP in the HS/HES group exceeded that in all other groups at T95 and T125 (P < .05). After a severe reduction in cerebral perfusion pressure (CPP), HS solutions (both HS and HS/HES) were associated with a delayed rise in ICP and did not improve global forebrain CBF in comparison with conventional saline solutions.

Impairment of cingulothalamic learning-related neuronal coding in rabbits exposed to cocaine in utero: general and sex-specific effects

Neuronal activity was recorded in the cingulate cortex and the limbic thalamus in Dutch-belted rabbits (Oryctolagus cuniculus) exposed to cocaine (8 mg/kg/day i.v.) or saline in utero during acquisition and reversal learning of a discriminative avoidance response. Anterior cingulate cortical excitatory training-induced activity (TIA) was attenuated in cocaine-exposed female rabbits during acquisition and reversal learning, but only during reversal learning in male rabbits. Posterior cingulate cortical excitatory TIA was lessened in cocaine-exposed rabbits during acquisition, whereas discrimination between the positive and negative cues was enhanced. Neuronal firing was attenuated in the anterior ventral thalamus in cocaine-exposed rabbits during acquisition and reversal learning. Behavioral learning was normal in cocaine-exposed rabbits. Other data suggest that rabbits exposed to cocaine in utero exhibit a learning deficit when trained with nonsalient cues.

Temporary vascular occlusion during cerebral aneurysm surgery

Temporary artery occlusion is an effective way to reduce the detrimental effects of intraoperative aneurysm rupture and to facilitate aneurysm dissection. The major risk incurred is of cerebral infarction. Dilemmas in the use of this technique include the amount of time that arterial flow may be interrupted safely and whether or not there is benefit to intermittent reperfusion. Protocol for the use of temporary occlusion is described.

Neurocytoma presenting with intraparenchymal cerebral hemorrhage

Neurocytomas are uncommon intracranial neoplasms that have only recently been characterized pathologically. Neurocytomas are histologically benign neoplasms that are often quite large when diagnosed, and previous reports have commonly described presentation with mass effect or cerebrospinal fluid outflow obstruction. We describe the first case of neurocytoma presenting with intraparenchymal cerebral hemorrhage.

Direct selection of conserved cDNAs from the DiGeorge critical region: isolation of a novel CDC45-like gene

We have used a modified direct selection technique to detect transcripts that are both evolutionary conserved and developmentally expressed. The enrichment for homologous mouse cDNAs by use of human genomic DNA as template is shown to be an efficient and rapid approach for generating transcript maps. Deletions of human 22q11 are associated with several clinical syndromes, with overlapping phenotypes, for example, velocardiofacial syndrome (VCFS) and DiGeorge syndrome (DGS). A large number of transcriptional units exist within the defined critical region, many of which have been identified previously by direct selection. However, no single obvious candidate gene for the VCFS/DGS phenotype has yet been found. Our technique has been applied to the DiGeorge critical region and has resulted in the isolation of a novel candidate gene, Cdc45l2, similar to yeast Cdc45p. [The sequence data described in this paper have been submitted to the EMBL data library under accession nos. AJ0223728 and AF0223729.]

Ethanol alters brain phospholipid levels which correlate with altered brain morphology

The effects of embryonic exposure on brain phospholipid levels were studied by injecting various concentrations of ethanol into fertile chicken eggs at 0 days of development. At 18 days of development, the levels of total phospholipids and various phospholipid classes were assayed in brain tissue and correlated to neuron densities within the cerebral hemispheres and the optic lobes. Although ethanol concentrations ranging from 0 to 3700 microns/Kg egg wt. failed to influence either total brain weight or total brain phospholipid levels, ethanol-induced changes in the levels of individual phospholipid classes were observed. When injected with 7 microns of ethanol/Kg egg wt., a 2- to 3-fold increase in brain phosphatidylethanolamine (PE) levels were observed with reduced levels of brain phosphatidylcholine (PC) and brain sphingomyelin (SP). When injected with 74 microns of ethanol/Kg egg wt., ethanol-induced increases in brain phosphatidylserine (PS) and PE were observed with ethanol-induced decreases in brain PC and SP. Cell fractionation studies demonstrated ethanol-induced increases in brain PE and PS and ethanol-induced decreases in brain PC and SP in nuclear, mitochondrial, and microsomal membranes. These ethanol-induced alterations in brain phospholipid profiles correlated with ethanol-induced reductions in neuron densities within the cerebral hemispheres and optic lobes.

Brain attack. The emergent management of hypertensive hemorrhage

Intracerebral hemorrhage (ICH) accounts for one half of stroke-related deaths, with hypertensive hemorrhage being the primary etiology. The evolution of minimally invasive devices for removal of ICHs, and the earlier delivery of patients for medical attention may have a great impact on the management of hypertensive hemorrhage.

Mortality rates, hospital length of stay, and the cost of treating subarachnoid hemorrhage in older patients: institutional and geographical differences

The risk of disability and death and the cost of medical care are particularly high for patients with aneurysmal subarachnoid hemorrhage (SAH) who are 65 years of age or older. A retrospective analysis of 47,408 Medicare patients treated over an 8-year period was performed to determine whether a relationship exists between the mortality rate and surgical volume for older patients with SAH. The mortality rate, length of stay in the hospital, and cost of treatment for patients with SAH in California and New York state were also compared. The mortality rate was 14.3% for patients with SAH who were 65 years old or older and who were treated surgically in hospitals in which an average of five or more craniotomies were performed per year; in hospitals averaging between one and five craniotomies annually the mortality rate was 18.4%; and in those averaging less than one such operation per year the rate was 20.5% (trend p = 0.01). There was no difference in the mortality rate for patients in California versus the rate for those in New York. Surgically and medically treated patients, respectively, left the hospital an average of 6.7 and 5.1 days sooner in California than in New York. The unadjusted average reimbursement from Medicare to hospitals for surgically treated patients averaged $1468 more in New York than in California (p < 0.0001), but was equivalent for medically treated patients in the two states. The mortality rate in older patients who are treated surgically for SAH may be inversely correlated with the annual number of craniotomies performed for SAH in patients 65 years of age or older at a given institution. Hospital stays for patients with SAH are significantly shorter in California than in New York.

Temporary vessel occlusion during intracranial aneurysm repair

Any method that decreases the risk of intraoperative rupture should improve outcome if complications associated with its use do not negate positive effect. If application time is limited and a form of cerebral protection and appropriate monitoring of cerebral function are used, temporary clip application may meet these requirements. The efficacy of temporary occlusion as an adjunct to aneurysm clipping may be limited by technical considerations with respect to regional anatomy, aneurysm size, and aneurysm consistency. In areas of limited access, positioning proximal clips may not be feasible. The use of endovascular techniques of balloon occlusion may provide proximal control in these situations (9, 106). The decision to use total circulatory arrest and profound hypothermia, as opposed to temporary clip application, remains largely a matter of the surgeon's judgment. The role of proximal parent vessel ligation must also be considered in the decision-making process regarding the treatment of giant or technically difficult aneurysms (114). Further refinements in cerebral monitoring that can accurately reflect intracellular processes in all territories affected by the application of temporary clips or balloon occlusion and development of more effective forms of cerebral protection may permit safer use of this technique. An adequately controlled clinical trial of temporary occlusion with or without putative "cerebral protection" is needed to confirm the efficacy of this technique.

Good clinical outcome in a patient with a large CT scan hypodensity treated with intra-arterial urokinase after an embolic stroke

Hypodense regions demonstrated by CT within 6 hours of the onset of stroke may reflect irreversibly damaged tissue, and some have suggested that patients with such findings should be spared the risks of thrombolytic therapy since they are unable to benefit from it. We report here a patient with a low-density area demonstrated by CT less than 6 hours after onset of symptoms who improved dramatically after successful intra-arterial thrombolysis.

The use of the eating disorder examination with children: a pilot study

OBJECTIVE

This article describes the use of a slightly modified version of the Eating Disorders Examination (EDE) in children.

METHODS

Sixteen children aged between 7 and 14 years attending an eating disorders clinic over a 5-month period were recruited to the study. The two main modifications to the EDE were (A) the inclusion of a sort task to assess overvalued ideas about weight and shape and (B) the reformulation of certain items to assess intent rather than actual behavior. The existing EDE scoring system was used, resulting in item, subscale, and global scores.

RESULTS

Of the 16 children (10 F 6 M), 11 had a diagnosis of anorexia nervosa, and 5 of eating disorder not otherwise specified (EDNOS). There were interesting differences in responses on items assessing core overvalued ideas, with weight and/or shape concerns emerging as of great importance in terms of self-evaluation in the majority of children with anorexia nervosa.

DISCUSSION

Results suggest that this may be a useful assessment tool in children, with some children obtaining global and subscale scores consistent with adult norms for females with eating disorders. Problems of the administration of the EDE to this patient group are discussed and details of the modifications used are outlined.

Idiom understanding in Australian youth: a cross-cultural comparison

In this developmental study, idiom understanding was examined in Australian students from Grades 5 and 8 (n = 50 per group; mean ages = 10.7 and 13.8, respectively). Twenty-four idioms with familiarity ratings ranging from high to low (as judged by Australian adolescents) were each presented in a brief story context. The students read each story and selected the best interpretation of the idiom from a set of four answer choices. Results indicated that performance on the task improved as a function of increasing grade level and that idiom familiarity was significantly correlated to idiom understanding for both groups of students. These results, which were consistent with a previous study of American students of comparable educational levels (Nippold & Taylor, 1995), provide further support for the "language experience" hypothesis of figurative language development. In replicating the previous developmental study, evidence of external validity is provided.

Cerebral arterial aneurysm formation and rupture in 20,767 elderly patients: hypertension and other risk factors

Cerebral arterial aneurysms are common in the general population and their rupture is a catastrophic event. Considerable uncertainty remains concerning the conditions that predispose individuals to aneurysm formation or rupture. The role of systemic hypertension in aneurysm formation and rupture has been especially controversial. Demographic variables have rarely been addressed because of the small sample sizes in previous studies. The authors describe the demographics and prevalence of hypertension in 20,767 Medicare patients with an unruptured aneurysm and compared these to a random sample of the hospitalized Medicare population. The prevalence of hypertension in patients with unruptured aneurysms was 43.2% compared with 34.4% in the random sample. Patients who survived their initial hospitalization were separated into two groups: those with an unruptured cerebral aneurysm as the primary diagnosis and those with an unruptured cerebral aneurysm as a secondary diagnosis. Follow-up data for 18,119 patients were examined to determine the risk of subarachnoid hemorrhage (SAH) associated with age, gender, race, hypertension, insulin-dependent diabetes mellitus, and surgical treatment. For patients with an unruptured cerebral aneurysm as the primary diagnosis, hypertension was found to be a significant risk factor for future SAH (risk ratio: 1.46, 95% confidence interval (CI): 1.01-2.11), whereas surgical treatment (risk ratio: 0.29, 95% CI: 0.09-0.97) had a significant protective effect. Advancing age had a small but significant protective effect in both groups. Elderly patients identified with unruptured aneurysms are more likely to have coexisting hypertension than the general hospitalized population. In elderly patients hospitalized with an unruptured cerebral aneurysm as their primary diagnosis, hypertension is a risk factor for subsequent SAH, whereas surgical treatment is a protective factor against SAH.

Idiom understanding in youth: further examination of familiarity and transparency

School-age children and adolescents (n = 150) enrolled in Grades 5, 8, and 11 were administered a forced choice task of idiom understanding that controlled for idiom familiarity and transparency. Performance on the task steadily improved during the targeted age range and was affected by the factors of interest: Idioms that were higher in familiarity and transparency were easier for students to understand than those that were less familiar and more opaque. The results of this study provide further support for the language experience hypothesis of figurative language development and for the hypothesis that metalinguistic activity, which itself becomes more sophisticated during the school-age and adolescent years, facilitates later language development. The study also suggests certain methodological implications for future research that examines the development of idiom understanding in youth.

Changing incidence and etiology of iatrogenic ureteral injuries

In the last decade there have been major advances in endoscopic surgery including ureteroscopy and laparoscopy, both of which may cause ureteral injury. We sought to determine if increased use of these procedures affected the frequency and nature of major iatrogenic ureteral injuries managed at our medical center. From 1980 to 1984 we treated 8 patients with such injuries compared to 19 patients treated from 1985 to 1989. The most recent period corresponded to the institution of ureteroscopy and the use of more aggressive laparoscopic procedures. Of the patients 14 sustained injuries at our center while 13 were referred from other institutions. Between 1985 and 1989 the incidence of injuries per total hospital admissions at risk increased from 4 to 11 per 10,000 (p = 0.0067), the incidence of urological injuries increased from 4 to 23 per 10,000 (p = 0.0071) and the incidence of injuries occurring in gynecologic patients increased from 13 to 41 per 10,000 admissions (p = 0.0385). There was no difference in the incidence of injuries in the general surgical population. From 1980 to 1984 no laparoscopic or ureteroscopic injuries occurred. However, from 1985 to 1989, 25% of gynecologic injuries occurred during laparoscopy and 70% of urological injuries were sustained during ureteroscopic procedures. Depending on the extent of the injury, patients were initially treated with either endourological or open surgical procedures. Good results were obtained in the majority of cases. Contemporary therapeutic strategies for treating patients sustaining ureteral injuries are discussed.

Incidence of renal anomalies in children prenatally exposed to ethanol

OBJECTIVE

Based on a number of studies involving animals as well as human case reports indicating an association between prenatal ethanol exposure and renal malformations, it has been suggested that children with fetal alcohol syndrome (FAS) should be screened for renal anomalies. The purpose of this study was to evaluate a group of children prenatally exposed to alcohol to determine the incidence of renal anomalies and to evaluate the need for such a screening procedure.

METHODS

Renal ultrasounds were performed on a total of 84 patients (68 children, 13 adolescents, and three adults). In addition to screening for malformations, renal size was studied. Data were analyzed using both chronologic and height-age as determinants of kidney size.

PATIENTS

Of these 84 patients, 51 (61%) had FAS, and 33 (39%) had a history of prenatal ethanol exposure but did not have FAS.

RESULTS

Three (3.6%) patients (one with FAS, two with prenatal ethanol exposure who did not have FAS) had significant renal abnormalities. This incidence was not significantly different from that found in ultrasound screening of newborns. The kidneys of children with both FAS and prenatal ethanol exposure who did not have FAS were significantly smaller than normal for both chronologic and height-age. When children were compared across chronologic ages, those with FAS had significantly smaller kidneys than those who had no evidence of FAS. After adjusting for height, the difference between these two groups was no longer significant.

CONCLUSIONS

Based on these data, children prenatally exposed to ethanol do not need to be screened for renal anomalies.

Doppler hemodynamic profiles of 82 clinically and echocardiographically normal tricuspid valve prostheses

BACKGROUND

Normal Doppler hemodynamics for tricuspid prostheses have not been well characterized in a large group of patients. Therefore, we analyzed comprehensive Doppler echocardiographic examinations of 82 patients with tricuspid prostheses that were normal by clinical and two-dimensional echocardiographic examinations to establish the normal hemodynamics of various types and sizes of tricuspid prostheses.

METHODS AND RESULTS

The earliest complete postoperative echocardiographic study from each patient was chosen for analysis. Doppler examinations were analyzed on an off-line station from tapes or Doppler strip charts. Early velocity, atrial velocity, end-diastolic velocity, pressure half-time, and mean gradient were obtained by digitizing tricuspid velocity curves. The incidence of "physiological" tricuspid prosthetic regurgitation was noted. Ten Doppler cycles were measured for each patient, and maximal, minimal, and average measurements were recorded. The mean values +/- SD of early velocity, atrial velocity, end-diastolic velocity, mean gradient, and pressure half-time and incidence of mild prosthetic regurgitation were reported for each type of prosthesis, as were highest Doppler measurements for each valve type. Average pressure half-time was significantly lower for St Jude than for heterograft prostheses (P = .04). There were no significant differences between the valve types for mean gradient, early velocity, or incidence of prosthetic regurgitation. Increasing prosthesis size was associated with lower average pressure half-time for heterograft prostheses (P = .024). Average differences (respiratory- and cycle-length-dependent) between maximal and minimal values for 10 cardiac cycles were established for each prosthesis.

CONCLUSIONS

This study establishes normal ranges for Doppler hemodynamics of various tricuspid prostheses and emphasizes the importance of measuring multiple cycles for each tricuspid prosthesis, regardless of cardiac rhythm.

Myelitis following chickenpox: a case report

An 18-year-old woman presented with myelopathic symptoms and a T-8 sensory deficit during a primary varicella infection. There were significant MRI changes in both the cervical and thoracic regions. Following treatment with steroids and intravenous acyclovir, the patient improved clinically and the abnormalities on MRI improved.

A homoallelic Gly317-->Asp mutation in ALPL causes the perinatal (lethal) form of hypophosphatasia in Canadian mennonites

We have discovered a single homoallelic nucleotide substitution as the putative cause of the perinatal (lethal) form of hypophosphatasia in Canadian Mennonites. Previous linkage and haplotype analysis in this population suggested that a single mutational event was responsible for this autosomal recessive form of hypophosphatasia. The mutation is a guanosine-to-adenosine substitution at nucleotide position 1177 in exon 10 of the tissue nonspecific (liver/bone/kidney) alkaline phosphatase gene. This Gly317-->Asp mutation segregates exclusively with the heterozygote phenotype we previously assigned by biochemical testing (maximum combined lod score of 18.24 at theta = 0.00). This putative disease-causing mutation has not been described in controls nor in other non-Mennonite probands with both lethal and nonlethal forms of hypophosphatasia studied to date. This Gly317-->Asp mutation changes a polar glycine to an acidic aspartate at amino acid position 317 within the highly conserved active site region of the 507-amino-acid polypeptide. Carrier screening for this lethal mutation in our high-risk population is now feasible.

Ocular tilt reaction resulting from vestibuloacoustic nerve surgery

The ocular tilt reaction (OTR) is a triad of head-eye synkinesis composed of head tilt, conjugate ocular torsion in the direction of head tilt, and skew deviation. The OTR represents a normal compensatory response to lateral head tilts and is produced by activation of the utricle of the lowermost ear. A pathological OTR results when otolith activity is unopposed as the result of injury to the opposite utricle or its nerve. Vertical diplopia may be the only symptom of OTR in patients who have undergone surgery involving the vestibuloacoustic nerve. We report a series of patients with OTR after surgery for acoustic neuroma or Meniere's disease. In each patient, the manifesting symptom was vertical diplopia. Bedside neuro-ophthalmological testing readily excluded a brain stem cause for the double vision. We conclude that OTR after vestibuloacoustic surgery is a benign condition with spontaneous resolution of symptoms within several months.

Regional cerebrovascular responses to progressive hypotension after traumatic brain injury in cats

We investigated the effects of hypotension on cerebral blood flow (CBF) after traumatic brain injury (TBI) in cats. Isoflurane-anesthetized cats were prepared for TBI and for microsphere measurements of total (T) and regional (r) CBF. Four groups were studied: sham injury (group I, n = 6); TBI (group II, n = 6); isoflurane anesthesia, no TBI or hypotension (group III, n = 4); and isoflurane and TBI, no hypotension (group IV, n = 8). After TBI or sham trauma, mean arterial pressure (MAP) was reduced to 80, 60, and 40 mmHg by hemorrhage. Group I TCBF did not change significantly from baseline until MAP reached 40 mmHg, but rCBF was more dependent on MAP in anterior hemispheric than in brain stem regions. Group II TCBF was significantly lower than baseline, and group I TCBF at all levels of hypotension and autoregulation was impaired at higher MAP levels in anterior than in posterior brain regions. Groups III and IV indicated that decreases in TCBF were not due to duration of the preparation or to TBI in the absence of hemorrhagic hypotension. We conclude that global and regional autoregulation are absent in response to hemorrhagic hypotension after TBI.

Measurement of globe position in complex orbital fractures. I. A modification of Hertel's exophthalmometer, using the external auditory canal as a reference point

Where there has been displacement or removal of the lateral orbital rim or zygomaticomaxillary complex secondary to trauma or surgery, the measure of globe position by the Hertel exophthalmometer is problematic and inaccurate. A modification of Hertel's instrument that uses the external auditory canal (EAC) rather than the orbital rim as reference point has been developed. Measurement of globe position of 120 normal volunteers was obtained with the Hertel and the modified EAC-fixated exophthalmometer. Although the mean absolute difference between right and left measurements for both methods (Hertel mean, 0.36 mm; modified mean, 0.51 mm; n = 120) differed statistically from 0 (p = 0.0001), that difference was not clinically significant. A more meaningful comparison was that of the variability of the two methods. The variance of the Hertel method (0.32) did not differ from the variance of the modified method (0.40; p = 0.06). No statistically significant difference was noted for sex (p = 0.33) or for race (p = 0.11). We believe this instrument to be of practical use in the assessment of enophthalmos or exophthalmos in patients whose facial deformity, trauma, surgery, or disease precludes the use of a rim-based exophthalmometry.

Reduced cerebral blood flow, oxygen delivery, and electroencephalographic activity after traumatic brain injury and mild hemorrhage in cats

The authors investigated the effects of transient, mild hemorrhagic hypotension after fluid-percussion traumatic brain injury on intracranial pressure, cerebral blood flow (CBF), cerebral oxygen delivery (CBF x arterial O2 content), and electroencephalographic (EEG) activity. Adult mongrel cats were anesthetized with 1.6% isoflurane in N2O:O2 (70:30) and prepared for trauma and for radioactive microsphere CBF measurement. Isoflurane concentration was decreased to 0.8%, and the cats were randomly assigned to one of four control groups or to an experimental group. Animals in the four control groups underwent either mild hemorrhage (18 ml.kg-1) immediately followed by resuscitation with equal volumes of 10% Hetastarch (eight cats), mild hemorrhage followed by replacement of shed blood (six cats), isovolemic hemodilution with 18 ml.kg-1 of Hetastarch (six cats), or moderate (2.2 atm) trauma alone (eight cats). The experimental group received a combination of trauma and mild hemorrhage followed by resuscitation with Hetastarch (eight cats). Mild hemorrhage produced no significant changes in CBF, renal blood flow, or cardiac output. Following resuscitation from mild hemorrhage, mean arterial blood pressure, cardiac output, renal blood flow, and CBF were not significantly different from baseline; cardiac output and renal blood flow did not differ significantly from baseline 2 hours after Hetastarch resuscitation. Neither hemorrhage nor trauma alone produced significant decreases in CBF or in EEG activity, but trauma followed by hemorrhage and resuscitation produced significant (p less than 0.01) decreases in CBF, cerebral oxygen delivery, and EEG score. These data demonstrate that, following traumatic brain injury, even mild hemorrhagic hypotension is associated with significant deficits in cerebral oxygen availability and neurological function.

HIV prevention: a dramaturgical analysis and practical guide to creating safer sex interventions

Safer sex is currently a major strategy for preventing HIV transmission. We examine safer sex interventions using an interactionist form of dramaturgical analysis. This approach yields a dynamic model with which to generate novel safer sex interventions highly sensitive to changing individual, cultural, and social variables. Our goal is to help medical anthropologists, applied social scientists, health educators, community outreach specialists, and those who are sexually active apply safer sex strategies more effectively.

Cerebrovascular and cerebral metabolic effects of alterations in perfusion flow rate during hypothermic cardiopulmonary bypass in man

Recent experimental and clinical investigations provide conflicting evidence regarding the effects of changes in the systemic flow rate from the pump oxygenator on cerebral blood flow and the cerebral metabolic rate of oxygen consumption. However, the results of existing clinical studies are difficult to interpret because of the confounding effects of differences in management of arterial carbon dioxide tension and use of anesthetic and vasoactive agents during cardiopulmonary bypass. To clarify the relationship among perfusion flow rate, cerebral blood flow, and cerebral metabolic rate of oxygen consumption in man during hypothermic cardiopulmonary bypass, we varied perfusion flow rate in random order to either 1.75 or 2.25 L.min-1.m-2 and studied cerebral blood flow (measured by clearance of xenon 133) and cerebral metabolic rate of oxygen consumption (estimated as the product of cerebral blood flow and the cerebral arteriovenous oxygen content difference) in patients managed with both the alpha-stat (group 1) and the pH-stat (group 2) methods of pH and arterial carbon dioxide tension adjustment. We measured the cerebral arteriovenous oxygen content difference using radial arterial and jugular venous bulb blood samples. In each patient other variables known to exert effects on cerebral blood flow and cerebral metabolic rate of oxygen consumption, including temperature, arterial carbon dioxide tension, arterial oxygen tension, mean arterial pressure, and hematocrit, were maintained constant between measurements. In both groups, mean arterial pressure at both pump flow rates was similar because of spontaneous reciprocal alterations in systemic vascular resistance, that is, as perfusion flow rate declined, systemic vascular resistance increased; as perfusion flow rate increased, systemic vascular resistance declined. Under these tightly controlled conditions, pump flow variation per se exerted no effect on cerebral blood flow or cerebral metabolic rate of oxygen consumption in either group.

Hypertonic/hyperoncotic fluid resuscitation after hemorrhagic shock in dogs

We compared canine systemic and cerebral hemodynamics after resuscitation from hemorrhagic shock with 4 mL/kg (a volume approximating 12% of shed blood volume) of 7.2% saline (HS; 1233 mEq/L sodium), 20% hydroxyethyl starch (HES) in 0.8% saline, or a combination fluid consisting of 20% hydroxyethyl starch in 7.2% saline (HS/HES). Eighteen endotracheally intubated mongrel dogs (18-24 kg) were ventilated to maintain normocarbia with 0.5% halothane in nitrous oxide and oxygen (60:40). After a 30-min period of hemorrhagic shock (mean arterial blood pressure = 40 mm Hg), extending from time T0 to T30, animals received one of three randomly assigned intravenous resuscitation fluids: HS, HES, or HS/HES. Data were collected at baseline, at the beginning and end of the shock period (T0 and T30), immediately after fluid infusion (T35), and at 60-min intervals for 2 h (T95, T155). After resuscitation, mean arterial blood pressure and cardiac output increased similarly in all groups, but failed to return to baseline. Intracranial pressure decreased during shock and increased slightly, immediately after resuscitation in all groups. During shock, cerebral blood flow (cerebral venous outflow method) declined in all groups. After resuscitation, cerebral blood flow increased, exceeding baseline in the HS and HS/HES groups but remaining low in the HES group (P less than 0.05 HS vs HES at T35). We conclude that small-volume resuscitation (4 mL/kg) with HS, HS/HES, or HES does not effectively restore or sustain systemic hemodynamics in hemorrhaged dogs. In dogs without intracranial pathology, the effects on cerebral hemodynamics are also comparable, except for transiently greater cerebral blood flow in the HS group in comparison with the HES group.

Regional cerebral blood flow following resuscitation from hemorrhagic shock with hypertonic saline. Influence of a subdural mass

After severe hemorrhage, hypertonic saline restores systemic hemodynamics and decreases intracranial pressure (ICP), but its effects on regional cerebral blood flow (rCBF) when used for resuscitation of experimental animals with combined shock and intracranial hypertension have not been reported. We compared rCBF changes (by radiolabeled microsphere technique) after resuscitation from hemorrhage with either 0.8 or 7.2% saline in animals with and without a right hemispheric subdural mass. We studied 24 mongrel dogs anesthetized with 0.5% halothane and 60% nitrous oxide. In group 1 (n = 12), hemorrhage reduced mean arterial pressure (MAP) to 45 mmHg for 30 min. In group 2 (n = 12), ICP was increased and maintained constant at 15 mmHg, whereas hemorrhage reduced MAP to 55 mmHg for 30 min (cerebral perfusion pressure [CPP] approximately 40 mmHg in each group). After the 30-min shock period, 6 animals in each group received one of two randomly assigned resuscitation fluids over a 5-min interval: 1) 7.2% hypertonic saline (HS; sodium 1,232 mEq.l-1, volume 6.0 ml.kg-1); or 2) 0.8% isotonic saline (SAL; sodium 137 mEq.l-1, volume 54 ml.kg-1). Once fluid resuscitation began, ICP was permitted to vary independently in both groups. Data were collected at baseline (before subdural balloon inflation in group 2), midway through the shock interval (T15), immediately after fluid infusion (T35), and 60 and 90 min later (T95, T155). In groups 1 and 2, ICP was significantly less in animals resuscitated with HS compared to those receiving SAL (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Sodium nitroprusside infusion does not dilate cerebral resistance vessels during hypothermic cardiopulmonary bypass

This study determined whether sodium nitroprusside (SNP) changes cerebral vascular resistance during stable, hypothermic cardiopulmonary bypass (CPB). Cerebral blood flow (CBF) was measured using Xenon clearance in 39 patients anesthetized with fentanyl. In 25 patients (group 1), CBF was measured before and during infusion of SNP at a rate sufficient to reduce mean arterial pressure (MAP) approximately 20%. In 14 other patients (group 2), CBF was measured before and during simultaneous infusion of SNP and phenylephrine; SNP was continued at a rate that had reduced MAP approximately 20% while phenylephrine was added in a dose sufficient to restore MAP to preinfusion levels. Patients within each group were randomized to maintenance of PaCO2 approximately 40 mmHg (groups 1a and 2a), uncorrected for body temperature, or to maintenance of PaCO2 approximately 50 mmHg (groups 1b and 2b). The following variables were maintained within a narrow range: nasopharyngeal temperature (26-29 degrees C), pump oxygenator flow (1.7-2.5 l.min-1.m-2), PaO2 (150-300 mmHg), and Hct (22-28 vol%). In each patient, controlled variables varied no more than +/- 5% between measurements. In group 1a (PaCO2 approximately 40 mmHg), MAP was 86 +/- 9 mmHg (mean +/- SD) before and 65 +/- 8 mmHg during SNP infusion (P less than 0.0001). CBF was 12 +/- 3 ml.100g-1.min-1 before and 10 +/- 2 ml.100(-1).min-1 during SNP infusion (P less than 0.01). In group 1b (PaCO2 approximately 55 mmHg), MAP was 86 +/- 11 mmHg before and 66 +/- 13 mmHg during SNP infusion (P less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of anatrophic nephrolithotomy and percutaneous nephrolithotomy with and without extracorporeal shock wave lithotripsy for management of patients with staghorn calculi

A retrospective study was conducted comparing anatrophic nephrolithotomy (10 cases), percutaneous nephrolithotomy alone (4 cases) or percutaneous nephrolithotomy combined with extracorporeal shock wave lithotripsy (23 cases) for the treatment of large staghorn calculi. A comparison based on collecting system anatomy demonstrated that anatrophic nephrolithotomy resulted in a greater stone-free rate, shorter hospitalization and lower costs while complication rates were similar. Anatrophic nephrolithotomy should still be considered a viable treatment option, especially for patients with large branched calculi in complex collecting systems.

Improved lung preservation with cold air storage

Conventional topical slush cooling limits lung transport to 4 to 6 hours. For this canine study of an alternate air cooling system, 37 canine lungs were removed: 24 were placed in plastic bags, and inserted in a Transplanthermm container at core air temperatures (n = 6 lungs each) of (A) 4 degrees C, (B) 8 degrees C, (C) 12 degrees C, and (D) 20 degrees C; 6 were stored conventionally in ice slush (E); and 7 were transplanted immediately (F). After 8 hours, the stored lungs were transplanted and the contralateral pulmonary artery was ligated. Survival, arterial oxygen tension, and extravascular lung water were monitored at 15 minutes and every hour for 4 hours. Four-hour survival was 100% in groups A, B, and F; 83% in group C, 50% in group D, and 17% in group E. The mean arterial oxygen tension at 1 hour was lower in group E (6.4 +/- 2.4 kPa) than in group A (39.8 +/- 13.2 kPa) (p = 0.0002) or in group F (42.0 +/- 16.2 kPa) (p = 0.0035). Extravascular lung water in group E was higher at 15 minutes (15.44 +/- 5.63 mL/kg) than in group A (3.76 +/- 0.63 mL/kg) (p = 0.0001) and group F (4.69 +/- 1.65 mL/kg) (p = 0.003). Cold air storage appears to provide better lung preservation than hypothermic immersion in ice slush.

Cerebrovascular Effects of Small Volume Resuscitation from Hemorrhagic Shock

To determine if hypertonic and hyperoncotic resuscitation solutions exerted comparable effects on cerebral hemodynamics following hemorrhagic shock, we compared randomly assigned, equal volumes (6.0 ml/kg) of hypertonic (7.2%) saline (HS) and hyperoncotic (20%) hydroxyethyl starch (HES) for resuscitation from acute experimental hemorrhage in 12 anesthetized dogs. Regional cerebral blood flow (radiolabeled microspheres), intracranial pressure (cisternal catheter), and systemic hemodynamics were recorded. Rapid hemorrhage reduced the mean arterial pressure to 45 mm Hg for 30 min. Resuscitation fluids were infused over 5 min. Both fluids restored mean arterial pressure and cardiac output equally. However, at 60 min following resuscitation, cardiac output decreased in the HS group in comparison to the HES group (1.7 +/- 0.1 vs. 3.1 +/- 0.2 L/min, p <0.05). Cardiac output rapidly declined, however, in the HS group in comparison to the HES group (p <0.05 60 min following resuscitation). Intracranial pressure and cerebral perfusion pressure were similar at all intervals. Regional cerebral blood flow was similar following both fluids. Neither fluid restored cerebral oxygen transport to baseline values. Based on these data, the authors conclude that, following severe hemorrhagic shock of brief duration, systemic and cerebral hemodynamic values are restored equally well by highly concentrated colloid or by hypertonic saline, although hypertonic saline only transiently improves cardiac output.

Small-volume resuscitation from hemorrhagic shock in dogs: effects on systemic hemodynamics and systemic blood flow

BACKGROUND AND METHODS

This study compared canine systemic hemodynamics and organ blood flow (radioactive microsphere technique) after resuscitation with 0.8% saline (Na+ 137 mEq/L), 7.2% hypertonic saline (Na+ 1233 mEq/L), 20% hydroxyethyl starch in 0.8% saline, or 20% hydroxyethyl starch in 7.2% saline, each in a volume approximating 15% of shed blood volume. Twenty-four endotracheally intubated mongrel dogs (18 to 24 kg) underwent a 30-min period of hemorrhagic shock, from time 0 to 30 min into the shock period, followed by fluid resuscitation. Data were collected at baseline, 15 min into the shock period, immediately after fluid infusion, 5 min after the beginning of resuscitation, and at 60-min intervals for 2 hr, (65 min after the beginning of resuscitation, and 125 min after the beginning of resuscitation). The animals received one of four randomly assigned iv resuscitation fluids: saline (54 mL/kg), hypertonic saline (6.0 mL/kg), hydroxyethel starch (6.0 mL/kg) or hypertonic saline/hydroxyethyl starch (6.0 mL/kg).

RESULTS

Mean arterial pressure increased in all groups after resuscitation. Cardiac output increased with resuscitation in all groups, exceeding baseline in the saline and hypertonic saline/hydroxyethyl starch groups (p less than .05 compared with hypertonic saline or hydroxyethyl starch). Sixty-five minutes after the beginning of resuscitation, cardiac output was significantly (p less than .05) greater in either of the two colloid-containing groups than in the hypertonic saline group. After resuscitation, hypertonic saline and hydroxyethyl starch produced minimal improvements in hepatic arterial flow, hypertonic saline/hydroxyethyl starch increased hepatic arterial flow to near baseline levels, and saline markedly increased hepatic arterial flow to levels exceeding baseline (p less than .05, saline vs. hydroxyethyl starch). One hundred twenty-five minutes after the beginning of resuscitation, hepatic arterial flow had decreased in all groups; hepatic arterial flow in the hypertonic saline group had decreased to levels comparable with those during shock. Myocardial, renal, and brain blood flow were not significantly different between groups.

CONCLUSIONS

Small-volume resuscitation with the combination of hypertonic saline/hydroxyethyl starch is comparable with much larger volumes of 0.8% saline, and is equal to hypertonic saline or hydroxyethyl starch in the ability to restore and sustain BP and improve organ blood flow after resuscitation from hemorrhagic shock.

Cerebral blood flow decreases with time whereas cerebral oxygen consumption remains stable during hypothermic cardiopulmonary bypass in humans

Recent investigations demonstrate that cerebral blood flow (CBF) progressively declines during hypothermic, nonpulsatile cardiopulmonary bypass (CPB). If CBF declines because of brain cooling, the cerebral metabolic rate for oxygen (CMRO2) should decline in parallel with the reduction in CBF. Therefore we studied the response of CBF, the cerebral arteriovenous oxygen content difference (A-VDcereO2) and CMRO2 as a function of the duration of CPB in humans. To do this, we compared the cerebrovascular response to changes in the PaCO2. Because sequential CBF measurements using xenon 133 (133Xe) clearance must be separated by 15-25 min, we hypothesized that a time-dependent decline in CBF would accentuate the CBF reduction caused by a decrease in PaCO2, but would blunt the CBF increase associated with a rise in PaCO2. We measured CBF in 25 patients and calculated the cerebral arteriovenous oxygen content difference using radial arterial and jugular venous bulb blood samples. Patients were randomly assigned to management within either a lower (32-48 mm Hg) or higher (50-71 mm Hg) range of PaCO2 uncorrected for temperature. Each patient underwent two randomly ordered sets of measurements, one at a lower PaCO2 and the other at a higher PaCO2 within the respective ranges. Cerebrovascular responsiveness to changes in PaCO2 was calculated as specific reactivity (SR), the change in CBF divided by the change in PaCO2, expressed in mL.100 g-1.min-1.mm Hg-1.(ABSTRACT TRUNCATED AT 250 WORDS)

Binding of S protein by Neisseria gonorrhoeae and potential role in invasion

An agglutination assay was used to examine the binding of purified human S protein (vitronectin, serum spreading factor) to 201 clinical isolates of Neisseria gonorrhoeae. Strains belonging to the protein IA serovars were significantly (P less than 0.001) more reactive in agglutination tests with human S protein and were more serum resistant than strains belonging to the protein IB serovars. The strains from patients with disseminated infections belonged predominantly to the IA serovar (19 of 23) and, with the exception of IA-4 and certain IB serovars, avidly agglutinated with S protein. The serovar IA-4 and IB strains isolated from joint or cerebrospinal fluid failed to agglutinate with S protein and appeared to be less serum resistant than most other IA isolates. Cysteine hydrochloride or 2-mercaptoethanol inhibited agglutination of S protein and a more than twofold increase in resistance to killing by fresh human serum following preincubation with S protein; the serum-sensitive parent strain did not agglutinate S protein, and serum resistance was not increased following preincubation with this protein. Binding of S protein by gonococci may represent a novel pathogenic mechanism that can contribute to serum resistance.