The reliability of quantitative electroencephalography as an indicator of cerebral ischemia

The electroencephalogram (EEG) has been used to detect episodes of cerebral ischemia during various surgical procedures. Recently, computerized systems for recording and interpreting the quantitative EEG (QEEG) have been used by anesthesiologists because of their ease of application, clarity of display, and reported ability to identify ischemic EEG changes. However, the extent to which automated techniques of QEEG interpretation reliably differentiate cerebral ischemia from the confounding effects of anesthetics and other sources of "artifact" is not completely established. In this study, EEGs were recorded before and after defibrillator testing in patients undergoing implantable cardioverter defibrillator (ICD) placement and during analogous time periods in control patients undergoing abdominal surgery. EEGs were subjected to standard visual inspection by an experienced electroencephalographer and QEEG analysis with a commercially available system was used for automated EEG interpretation in order to evaluate the reliability of this quantitative technique. The CIMON technique identified episodes which met previously defined criteria for QEEG cerebral dysfunction and ischemic pattern in both groups, despite the presumed absence of cerebral ischemia in the control patients. Since there was no evidence of cerebral ischemia in the raw EEGs of either the ICD patients or the controls, these QEEG changes were not confirmed by conventional techniques of EEG interpretation. Our results suggest that caution is warranted when using automated systems for intraoperative interpretation of EEG.

The humanities and nursing: using popular literature as a means of understanding human experience

The rapid advances in technology during the twentieth century have encouraged science and technology to be the main focus of the nursing curricula. The effect of this focus tends to hinder the importance of the human condition. This paper discusses the benefits of including the humanities, particularly but not exclusively the inclusion of literary study in nursing curricula. It is argued that the study of popular literature by students of nursing provides them with the opportunity to understand and to appreciate life experiences. This assists them in gaining awareness and sensitivity to the many physical and psychological components of people's reactions to health, illness and hospitalization. The power of literary study to promote an appreciation of the hurt and pain of disease is considered by the authors to be an effective teaching tool within a comprehensive programme for students of nursing.

Coronary artery aneurysms after angioplasty and atherectomy

Coronary artery aneurysm formation after percutaneous transluminal coronary angioplasty and directional coronary atherectomy is unusual. We report the case of a left anterior descending coronary artery aneurysm that formed in such a patient. The left anterior descending coronary artery was bypassed and the aneurysm was plicated with the aid of coronary angioscopy. The English-language medical literature on the topic of coronary artery aneurysms is reviewed.

Implantable cardioverter-defibrillator. Evaluation of clinical neurologic outcome and electroencephalographic changes during implantation

During placement of implantable cardioverter-defibrillators, ventricular arrhythmias are induced to test the function of the devices. Although cerebral hypoperfusion and ischemic electroencephalographic changes occur in patients while implantable cardioverter-defibrillators are being tested, no investigation has assessed neurologic outcome in these patients. Nine patients having either implantation or change of an implantable cardioverter-defibrillator underwent neurologic examination and neuropsychometric tests before and after the operation. After induction of general anesthesia and insertion of implantable cardioverter-defibrillator leads (when needed), ventricular fibrillation, ventricular flutter, or ventricular tachycardia, was induced by means of programmed electrical stimulation. Implantable cardioverter-defibrillator testing continued until satisfactory lead placement was confirmed. The intraoperative electroencephalographic recording was analyzed for evidence of ischemic change. In all, an electroencephalogram was recorded during 50 periods of circulatory arrest. Mean duration of the arrest periods was 13.6 seconds. By means of conventional visual inspection of the raw electroencephalogram, high-amplitude rhythmic delta or theta, voltage attenuation, or loss of fast frequency activity was observed in 30 of the arrests. By means of an automated technique of electroencephalographic interpretation based on power spectral analysis, electroencephalographic changes were correctly identified in 26 of the arrests. The incidence of these electroencephalographic changes was dependent on the arrest duration. The mean interval from arrest onset to electroencephalographic change was 7.5 seconds (standard deviation +/- 1.8 seconds). In patients with electroencephalographic changes during multiple arrests, no downward trend in this interval was detected in later arrests and no evidence of persistent ischemic change was observed in electroencephalograms recorded after the conclusion of implantable cardioverter-defibrillator testing. Postoperative neurologic and neuropsychometric testing was completed in eight patients, none of whom exhibited a new neurologic deficit, exacerbation of a preexisting neurologic condition, or significant deterioration in neuropsychometric performance. We conclude that the brief arrest of cerebral circulation induced during insertion of an implantable cardioverter-defibrillator is not associated with permanent neurologic injury.

Molecular analysis of the Methoprene-tolerant gene region of Drosophila melanogaster

Adult functions of juvenile hormone (JH) have been described for Drosophila melanogaster and other dipteran insects, but preadult function for this hormone remains largely unknown in this order of insects. We have identified a mutation of Drosophila, Methoprene-tolerant (Met), which appears to alter JH reception during late larval development. The molecular cloning of Met will be a step toward understanding this gene and possibly identifying a preadult role(s) for JH. Molecular cloning was initiated using the technique of transposon-tagging with a transposable P element. P-element insertional alleles of Met were generated, and genomic libraries were constructed from two of these alleles. From these libraries P-element-bearing clones were isolated that in situ hybridized to the cytogenetic region where Met had been previously localized by genetic methods. Two of the alleles were shown to have complete P-elements inserted in similar, but not identical, locations in the predicted cytogenetic region where Met is located. A late-larval cDNA library was screened to identify transcriptional units in this region, and clones were recovered with homology to a DNA fragment abutting the P-element insertion site. These clones may represent Met cDNA molecules.

Transplacental antibody transfer following maternal immunization with polysaccharide and conjugate Haemophilus influenzae type b vaccines

Passive transfer of antibody to infants born to women immunized during the third trimester of pregnancy with a Haemophilus influenzae type b (Hib) vaccine (PRP polysaccharide or Hib conjugates PRP-D or HbOC) was studied in 50 mothers and infants and 47 nonimmunized mother-infant pairs. Geometric mean total PRP antibody by RIA was 1.2 micrograms/mL at delivery in unimmunized women and 21, 149, and 171 micrograms/mL in women who received PRP, PRP-D, and HbOC, respectively. Mean cord PRP antibody levels were 0.29, 3.0, 17.5, and 29.3 micrograms/mL for the corresponding groups. Postimmunization and cord PRP antibody levels were higher after maternal immunization with conjugate vaccines than with PRP vaccine (P < .01). PRP IgG1 subclass was transmitted more efficiently than IgG2 (56% vs. 35%, P < .01). The proportion of anti-PRP IgG transmitted from immunized mothers to infants correlated with time between immunization and delivery. Administration of PRP conjugate vaccines to women during pregnancy resulted in higher levels of PRP antibodies in infants than did polysaccharide or no vaccine.

Ex vivo two-dimensional proton nuclear magnetic resonance spectroscopy of smooth muscle tumors: advantages of total correlated spectroscopy over homonuclear J-correlated spectroscopy

Two-dimensional total correlated proton nuclear magnetic resonance spectroscopy (TOCSY) at 600 MHz was used for an ex vivo biochemical analysis of a benign human smooth muscle tumor (leiomyoma) and high grade malignant smooth muscle tumor (leiomyosarcoma). While there are a number of applications of proton nuclear magnetic resonance magnitude-mode two-dimensional correlated spectroscopy (COSY) to the ex vivo study of tissues and cells in the literature, to our knowledge this is the first application of TOCSY for the ex vivo study of biological tissue. Comparison of TOCSY and purged COSY data demonstrate the potential sensitivity advantages of the TOCSY method for the study of heterogeneous biological tissues. These TOCSY spectra were used to identify and quantitate a wide range of metabolites such as amino acids, peptides, triglycerides, phospholipid precursors and degradation products, bound fucose, and other saccharides. The leiomyosarcoma was found to have 5-fold higher levels of triglycerides and a 7-fold increase in the glycerophosphocholine:choline ratio compared to the leiomyoma. These metabolite changes may enhance membrane fluidity in the leiomyosarcoma compared to leiomyoma and thus may be of fundamental importance to cell motility, recognition, sarcoma tumorigenesis, and metastatic potential.

Children awaiting invasive medical procedures: do children and their mothers agree on child's level of anxiety?

Examined correspondence between mother and child reports of child anxiety immediately preceding a scheduled invasive medical procedure. The State-Trait Anxiety Inventory for Children (STAIC) was administered to 101 children ages 10-18 years. Mothers completed the STAIC and the State-Trait Anxiety Inventory to assess their perceptions of the child's anxiety and their own level of anxiety, respectively. Children were reported to have significantly more state anxiety as perceived by themselves and their mothers relative to the normative sample. Results also revealed low overall mother-child correspondence on child anxiety, particularly for mothers reporting more anxiety in themselves. Additionally, while age, gender, and socioeconomic status were not associated with mother-child correspondence, an unexpected relationship between race and correspondence emerged. Overall, our findings indicate that reliance on parents' perceptions of child anxiety prior to an invasive medical procedure is not sufficient.

Long-term follow-up after total parathyroidectomy without parathyroid reimplantation in chronic renal failure

Forty-three patients with secondary or autonomous hyperparathyroidism complicating chronic renal failure (CRF) underwent total parathyroidectomy (PTX) (follow-up 2-18 years, mean 8.7 years). Five were on conservative treatment for CRF, 35 on regular dialysis, and only three had a functioning allograft. At PTX, the most frequent findings were uncontrollable hypercalcaemia, musculo-skeletal pain, radiographic changes in the phalanges, and raised plasma parathyroid hormone (PTH) concentration. Pre-operatively, all patients were loaded with dihydrotachysterol or 1-alpha-OH cholecalciferol. Postoperatively, they were maintained on tapering doses of the same drugs and, briefly, oral calcium supplements. Five glands were identified and removed in two patients, four in 35 patients, three in three patients and only two in one patient. All had changes of hyperplasia and adenoma formation, except for one with a parathyroid carcinoma. Prompt symptomatic and radiographic improvement occurred, with normalization of plasma calcium and alkaline phosphatase. Postoperative PTH levels were available in 33 patients (23 by intact PTH assay): they were persistently high in 10/33 (2/23 intact); normal in seven (6 intact); low in 11 (3 intact), and undetectable in four (3 intact). Thus, PTX was incomplete in the majority of patients. Following transplantation, 3/20 (3/18 intact) patients still had detectable PTH. Only one patient developed symptomatic recurrent parathyroid disease requiring re-operation, and complications were few. Small dosages of vitamin D continue to be required, but not calcium supplementation, and no clinical effects of possible adynamic bone have been noted. At later renal transplantation in 27 patients, an easily treatable, uncomplicated hypocalcaemia was noted in 33%.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of recurrent suprahyoid cervicofacial lymphangioma with intravenous cyclophosphamide

PURPOSE

Surgical resection of cervicofacial cystic hygromas and lymphangiomas rarely effects complete reduction because of severe anatomic restrictions.

PATIENTS AND METHODS

With prior knowledge of cyclophosphamide activity against lesions of this type, a formal trial of cyclophosphamide was initiated.

RESULTS

Overall dose escalation therapy resulted in 50% reduction in mass without recurrence after cessation of therapy and with minimal and readily reversible toxicity.

CONCLUSIONS

The favorable responses to cyclophosphamide in this study suggest that a prospective randomized trial should be initiated. Certainly, children who have airway and/or esophageal compromise who have failed surgical therapies should be considered for cyclophosphamide treatment.

Is thrombolysis of occluded popliteal and tibial bypass grafts worthwhile?

PURPOSE

We analyzed the short- and long-term results for patients undergoing thrombolysis of occluded infrainguinal bypass grafts at our institution over a 62-month period.

METHODS

Thirty-one patients with 40 episodes of graft thrombosis in 33 grafts managed by thrombolysis were retrospectively reviewed. The effects of graft age, material, and anatomy, symptoms, treatment, anticoagulation, and occlusion duration were evaluated for impact on patency after thrombolysis. Dose and duration of therapy with use of the technique of pulse-spray thrombolysis was assessed.

RESULTS

Thrombolysis successfully reestablished patency in 92% of grafts treated. Mean lysis time and urokinase dose were 118 minutes and 607,000 units, respectively. Responsible lesions were identified and treated by angioplasty or surgery in 35 of 37 cases. The patency rate after thrombolysis was 28% at 30 months, and the secondary patency rate was 46% at 18 months. Duration of occlusion, symptoms, treatment, graft anatomy, and prior graft revision did not impact on patency. Mean secondary patency was 21.5 months in grafts in place over 1 year and 7.0 months in grafts in place for less than 1 year. Mean secondary patency was 23.8 months in polytetrafluoroethylene grafts and 8.4 months in vein grafts. The limb salvage rate was 84% at 30 months, and the patient survival rate was 84% at 42 months.

CONCLUSIONS

Pulse-spray thrombolysis is effective in rapidly recanalizing thrombosed infrainguinal grafts. Grafts failing in the first year after placement should generally be replaced, reserving thrombolysis and revision for grafts greater than 1 year old. Vein grafts tolerate thrombosis less well than synthetic conduits and have decreased long-term patency.

Physical proximity as a possible facilitator in post-detoxification treatment-seeking among chemically dependent veterans

The transition into rehabilitative treatment following detoxification is a critical event for most chemically dependent individuals. A host of factors may enhance or impede this transition, yet little or no research has been done to shed light on this issue. This paper presents the results of the fortuitous changing of one variable which appeared to increase the likelihood of a successful transition, namely, the degree of physical proximity of the detox program and the rehab program. Results indicated a significantly greater proportion of patients successfully making the transition from detox to rehab when the programs were very close proximally than when they were less close. The role of possible patient-to-patient modeling effects was discussed.

Blood volume responses of men and women to bed rest

This paper reviews a series of studies that indicate that estrogens play an important role in blood volume regulation. The first study illustrates that the plasma volume (PV) of ambulatory women fluctuates during the menstrual cycle, increasing during periods of elevated estrogens. In the second study, it was shown that exogenous and endogenous elevations in blood estrogens attenuate the decrease in PV during bed rest. In the third study, the hypothesis was tested that women, who naturally have a higher blood estrogen content compared with men, will have a smaller loss of PV during bed rest. Ten men and ten women underwent a 13-day, 6 degrees head-down bed rest. Plasma volume and red cell mass (RCM) were measured before and after bed rest using 125I and 51Cr labeling, respectively. Before bed rest, the men and women had similar blood volume (BV) and PV (mL/kg body weight), but the women had a smaller (P < .01) RCM (22.2 +/- 0.9 versus 26.2 +/- 0.8 mL/kg, mean +/- SE). During bed rest, the decrease in RCM (mL/kg) was similar in men and women. However, the decrease in BV was greater in men (8.0 +/- 0.8 mL/kg versus 5.8 +/- 0.8 mL/kg), because of a greater reduction in PV (6.3 +/- 0.6 mL/kg versus 4.1 +/- 0.6 mL/kg). Because the decline in BV has been proposed to contribute to the cardiovascular deconditioning after bed rest, it is possible that women may experience less cardiac and circulatory strain on reambulation.

Arterial or mixed venous lactate measurement in critically ill children. Is there a difference?

Seven critically ill children had simultaneous measurement of whole blood lactate concentrations obtained from a systemic arterial and mixed venous (pulmonary artery) site. An excellent correlation was found (r = 0.995). The mean difference between arterial and mixed venous values was 0.02 mmol/l and the limits of agreement (+/- 0.22) were -0.20 to 0.24. The differences found were clinically insignificant (two-tailed paired Student's t-test; p = 0.36) and therefore support the continued use of arterial sampling for blood lactate measurement.

Dimensions associated with successful implementation of a hospital based integrated order entry system

Implementation of an integrated electronic medical record requires direct physician order entry. This application involves multi-level changes in the whole system of care, from physicians attitudes to interdepartmental relations. This study reports the results of the first round of a modified Delphi, where a diverse group of individuals were asked to identify the most important facilitating and impeding factors associated with implementation of an order entry application. From a Q-sort of their responses, we identified 20 systemic, behavioral, and attitudinal dimensions perceived to be causal factors in successful implementation. We also explored how these dimensions may influence success by comparing successful with unsuccessful hospitals in terms of the frequency with which these dimensions were differently mentioned by respondents. We found that although available functionality was the most commonly mentioned factor by all participants, hardware availability, physician involvement, administration support, and medical administration involvement were more often mentioned by successful hospitals than by less successful hospitals. These results suggest that these factors were not present in the less successful hospitals. We also found that the frequency of responses within each category varied depending on the institutional role of the individuals responding. Those involved in support tended to see organizational variables as more important than those in clinical positions, whereas clinicians viewed administrative support and involvement of the chief as more important. These findings support the notion that the changes involved in instituting a physician order entry system are system wide and involve individual as well as organizational factors.

The risk of alcohol

We have reviewed 156 papers which provided sufficient information to relate individual alcohol consumption to risk for a variety of physical damage. Overall, there was evidence for a dose-response relationship between level of alcohol consumption and risk of harm for liver cirrhosis, cancers of the oropharynx, larynx, oesophagus, rectum (beer only), liver and breast, and blood pressure and stroke. An increased risk of cardiac arrhythmias, cardiomyopathy and sudden coronary death was associated with heavy drinking. There was evidence for a protective effect of alcohol consumption against risk of coronary heart disease, which could be achieved at consumption levels of less than 10 g alcohol a day. The mortality of non-drinkers was higher than that of moderate drinkers in some studies. Level of alcohol consumption and total mortality were dose-related when non-drinkers were excluded. The finding of a dose-relationship between alcohol and harm suggested causality. It was not possible to define individual risk for all harms at a given level of alcohol consumption because of variations in methodology, but some idea of the order of magnitude of the increased risk can be obtained from calculating trends of pooled log-odds ratios. At levels of alcohol consumption of more than 20-30 g a day, all individuals are likely to accumulate risk of harm. Current guidelines on upper limits of lower risk drinking in different countries (168-280 g of alcohol a week for men and 84-140 g a week for women) reflect levels at which the risk of total mortality is not greatly increased above one.

Variability in the risk of major gastrointestinal complications from nonaspirin nonsteroidal anti-inflammatory drugs

BACKGROUND

We have assessed the extent to which the risk of serious gastrointestinal complications from nonaspirin nonsteroidal anti-inflammatory drugs (NANSAIDs) varies with the age and sex of recipients, use of aspirin or alcohol, administration by the oral or rectal route, and dose and choice of drug.

METHODS

A case-control study was performed with prospective recruitment of cases of gastrointestinal bleeding or ulcer perforation and age- and sex-matched controls. Information on preadmission drug use obtained by structured interview.

RESULTS

Six hundred forty-four patients and 1268 controls were recruited. The odds ratio for upper gastrointestinal complications in users compared with nonusers of NANSAIDs increased with age: < or = 59 years, odds ratio 2.0; 60-79 years, odds ratio 3.0; > or = 80 years, odds ratio 4.2; and was higher in women (5.4) than in men (1.9). There was a linear dose-response curve that was steeper in women than in men. Combined exposure suggested additive risks: NANSAIDs and aspirin, odds ratio 6.7; NANSAIDs and alcohol, odds ratio 6.0 NANSAIDs by the oral route were associated with an odds ratio of 2.3, compared with 11.4 with rectal administration. Piroxicam was associated with the highest risk, odds ratio 4.8; and ibuprofen the lowest risk, odds ratio 0.7.

CONCLUSIONS

A number of factors can alter the risk of major gastrointestinal complications with NANSAIDs and need to be considered when individual prescribing decisions are made.

Comparison of the abundance of the fecal sterol coprostanol and fecal bacterial groups in inner-shelf waters and sediments near Sydney, Australia

Concurrent measurement of the sewage tracer coprostanol and fecal indicator bacteria were made for water and sediments collected in January 1992 from coastal waters off Sydney, Australia. The coprostanol results were compared with data from an earlier survey conducted in 1989 before the commisioning of Sydney's deepwater ocean outfalls in 1990 and 1991. Good correlations were observed for both water and sediment samples between coprostanol and the two fecal indicator organisms, fecal coliforms and Clostridium perfringens spores, thereby validating the use of coprostanol as a sewage signature in this environment. For sediments, most inner-shelf sites (1-10 km offshore) showed an increase in the concentration of coprostanol between the two surveys. The areas of highest concentration have been shifted further off-shore, to zones adjacent to the diffusers.