Motives for Sex and Sexual Perpetration in College Men: An Exploratory Study

OBJECTIVE

Prior research has rarely focused on sexual motives (e.g., motives for having sex) when studying sexual violence perpetration prevention. The current study examined the role of sexual motives alongside other risk factors like alcohol expectancies in predicting sexual violence.

METHOD

We analyzed data from 205 male college students; 36% reported sexual perpetration of some type. Participants completed a series of questionnaires in a randomized order, including: measures of prior sexual perpetration, sexual motives, rape myth acceptance, alcohol expectancies, and a measure of social desirability. Data were analyzed using a series of T-tests and logistic regressions.

RESULTS

With one exception (coping motives), all sexual motives (intimacy, enhancement, self-affirmation, peer approval, and partner approval) were endorsed at higher levels by individuals who perpetrated sexual violence than those who did not (p < .05, Cohen's d = .25-.56). The partner approval motive significantly predicted sexual violence perpetration on its own. The enhancement motive, both independently and in interaction with alcohol expectancies for aggression, predicted sexual violence perpetration. Two other motives, intimacy and self-affirmation, were only significant in interaction with alcohol expectancies for aggression.

CONCLUSION

All sexual motives were endorsed more frequently by those who perpetrated sexual violence than those who did not. Sexual motives had a complex interaction with alcohol expectancies in predicting sexual violence perpetration. The results suggest that intervention programs should emphasize healthy, consensual sexual relationships that do not involve alcohol.

Environmental niches and metabolic diversity in Neoarchean lakes

The diversification of macro-organisms over the last 500 million years often coincided with the development of new environmental niches. Microbial diversification over the last 4 billion years likely followed similar patterns. However, linkages between environmental settings and microbial ecology have so far not been described from the ancient rock record. In this study, we investigated carbon, nitrogen, and molybdenum isotopes, and iron speciation in five non-marine stratigraphic units of the Neoarchean Fortescue Group, Western Australia, that are similar in age (2.78-2.72 Ga) but differ in their hydro-geologic setting. Our data suggest that the felsic-dominated and hydrologically open lakes of the Bellary and Hardey formations were probably dominated by methanogenesis (δ¹³ C_org  = -38.7 ± 4.2‰) and biologic N₂ fixation (δ¹⁵ N_bulk  =-0.6 ± 1.0‰), whereas the Mt. Roe, Tumbiana and Kylena Formations, with more mafic siliciclastic sediments, preserve evidence of methanotrophy (δ¹³ C_org as low as -57.4‰, δ¹³ C_carb as low as -9.2‰) and NH₃ loss under alkaline conditions. Evidence of oxygenic photosynthesis is recorded only in the closed evaporitic Tumbiana lakes marked by abundant stromatolites, limited evidence of Fe and S cycling, fractionated Mo isotopes (δ^98/95 Mo = +0.4 ± 0.4‰), and the widest range in δ¹³ C_org (-57‰ to -15‰), suggesting oxidative processes and multiple carbon fixation pathways. Methanotrophy in the three mafic settings was probably coupled to a combination of oxidants, including O₂ and SO₄^2- . Overall, our results may indicate that early microbial evolution on the Precambrian Earth was in part influenced by geological parameters. We speculate that expanding habitats, such as those linked to continental growth, may have been an important factor in the evolution of life.

Validation-verification of a highly effective, practical human testicular tissue in vitro culture-cryopreservation procedure aimed to optimize pre-freeze and post-thaw motility

PURPOSE

The aim of our paper was to validate a testicular biopsy procedure that simplifies handling, processing, and cryopreservation, while at the same time optimizes sperm motility before freezing and after thawing.

METHODS

Two prospective studies were conducted to verify, optimize, and understand the virtues of pre-freeze testicular tissue IVC at different temperatures (21, 30, or 37 °C). Testicular tissue was obtained from clinical specimens designated for whole tissue cryopreservation (i.e., intact mass of tubules) and/or for fresh use in IVF-ICSI cycles. Whole testicular biopsy pieces (1-3 mm(3)) were diluted in glycerol containing freeze solutions, slow cooled to 4 °C and then rapidly frozen in LN2 vapor. Fresh and post-thaw testicular biopsy tissue were evaluated for changes in the quantity (%) and pattern of motility (I-IV: twitching to rapid progression, respectively) over a 1 week duration. The clinical effectiveness of IVC-cryopreserved whole testicular biopsy tissue was also validated analyzing fresh embryo transfers.

RESULTS

More reliable recovery of motile testicular sperm was achieved using whole tissue freeze preservation combined with IVC (24-96 h) post-acquisition at an incubation temperature of 30 °C compared to ambient temperature (21 °C) or 37 °C. Up to 85 % of the pre-freeze motility was conserved post-thaw (+3 h) for easy ICSI selection. Sperm longevity was optimized to fresh tissue levels by implementing testicular biopsy sucrose dilution post-thaw. Favorable clinical outcomes were proven using frozen-thawed testicular biopsy sperm for ICSI.

CONCLUSIONS

By employing minimal tissue manipulation, integrating pre-freeze IVC processing at 30 °C and the freezing of whole testicular biopsy tissue, we have reduced the labor and improved the efficacy of processing testicular tissue for freeze-preservation and subsequent ICSI use.

Influence of Adhesive Core Buildup Designs on the Resistance of Endodontically Treated Molars Restored With Lithium Disilicate CAD/CAM Crowns

OBJECTIVE

To assess the influence of adhesive core buildup designs (4-mm buildup, 2-mm buildup, and no buildup/endocrown) on the fatigue resistance and failure mode of endodontically treated molar teeth restored with lithium disilicate computer-aided design/computer-aided manufacturing (CAD/CAM) complete crowns placed with self-adhesive cement.

METHODS AND MATERIALS

Forty-five extracted molars were decoronated at the level of the cementoenamel junction and endodontically treated. Specimens received different Filtek Z100 adhesive core buildups (4-mm buildup; 2-mm buildup; and no buildup endocrown preparation) and were restored with Cerec 3 CAD/CAM lithium disilicate crowns (IPS e.max CAD). The intaglio surfaces of restorations (n=15) were conditioned by hydrofluoric acid etching and silane, and prepared teeth were treated with airborne-particle abrasion, followed by cementation with RelyX Unicem 2 Automix. Specimens were then subjected to cyclic isometric loading at 10 Hz, beginning with a load of 200 N (×5000 cycles), followed by stages of 400, 600, 800, 1000, 1200, and 1400 N at a maximum of 30,000 cycles each. Specimens were loaded until failure or to a maximum of 185,000 cycles. The chewing cycle was simulated by an isometric contraction (load control) applied through a 10-mm in diameter composite resin sphere (Filtek Z100). Surviving specimens were axially loaded until failure or to a maximum load of 4500 N (crosshead speed 0.5 mm/min). The failure mode was assessed, and fractures were designated as catastrophic (tooth/root fracture that would require tooth extraction) or reparable (cohesive or cohesive/adhesive fracture of restoration only). Groups were compared using the life table survival analysis (log-rank test at p=0.05). Surviving specimens were loaded to failure and compared with one-way analysis of variance.

RESULTS

The survival rates after the fatigue test were 100%, 93%, and 100% for 4-mm, 2-mm, and no buildup (endocrown), respectively and were not statistically different (only one specimen failed with a 2-mm buildup under a crown that cohesively fractured at 1,400 N). Postfatigue load to failure averaged 3181 N for 4-mm buildups (15 specimens), 3759 N for 2-mm buildups (12 specimens), and 3265 N for endocrowns (14 specimens). The 2-mm buildups were associated with higher loads to failure than endocrowns and 4-mm buildups, but no differences were found between 4-mm buildups and endocrowns (p<0.05.) One endocrown and 2 restorations with a 2-mm buildup survived the load-to-failure test (at 4500 N). Only catastrophic fractures occurred after the load-to-failure test.

CONCLUSIONS

The buildup design influenced the performance of endodontically treated molars restored with lithium disilicate CAD/CAM complete crowns placed with self-adhesive resin cement. The 2-mm buildups were associated with higher loads to failure than the endocrown and the 4-mm buildup, but all restoration designs survived far beyond the normal range of masticatory forces.

Influence of No-Ferrule and No-Post Buildup Design on the Fatigue Resistance of Endodontically Treated Molars Restored With Resin Nanoceramic CAD/CAM Crowns

Objectives

To evaluate the influence of adhesive core buildup designs—4-mm buildup, 2-mm buildup, and no buildup (endocrown)—on the fatigue resistance and failure mode of endodontically treated molar teeth restored with resin nanoceramic (RNC) CAD/CAM complete crowns placed with self-adhesive resin cement.

Methods and Materials

Forty-five extracted molars were decoronated at the level of the cementoenamel junction, and the roots were endodontically treated. Specimens received different Filtek Z100 adhesive core buildups (4-mm buildup, 2-mm buildup, and no buildup, endocrown preparation) and were restored with Cerec 3 CAD/CAM RNC crowns (Lava Ultimate). Restorations (n=15) and prepared teeth were treated with airborne-particle abrasion, followed by cementation with RelyX Unicem 2 Automix. Specimens were then subjected to cyclic isometric loading at 10 Hz, beginning with a load of 200 N (for 5000 cycles), followed by stages of 400, 600, 800, 1000, 1200, and 1400 N at a maximum of 30,000 cycles each. Specimens were loaded until failure or to a maximum of 185,000 cycles (10-mm-diameter composite resin sphere antagonist). The failure mode was assessed: “catastrophic” (tooth/root fracture that would require tooth extraction), “possibly reparable” (cohesive/adhesive failure with fragment and minor damage, chip or crack, of underlying tooth structure), or “reparable” fracture (cohesive or cohesive/adhesive fracture of restoration only). Groups were compared using the life table survival analysis. Intact specimens were loaded to failure and compared with one-way analysis of variance.

Results

All specimens survived the fatigue test until the 800 N-step. The survival rates for 4-mm, 2-mm, and no buildup (endocrown) were 53%, 87%, and 87%, respectively, and were not statistically different even though crowns with 2-mm buildups only started to fail at 1200 N. Minor cohesive chips were detected in many samples despite having survived all 185,000 cycles. Postfatigue load-to-failure ranged from 2969 N with 4-mm buildup (eight specimens), 2794 N for 2-mm buildup (13 specimens), and 2606 N for endocrowns (13 specimens) and were also not statistically different. There were only two catastrophic failures during the fatigue test and small subgingival delamination fractures and cracks (only with 4-mm buildup). All specimens in the load-to-failure test exhibited nonrestorable catastrophic fractures.

Conclusions

There was no influence of the buildup design on the performance of endodontically treated molars restored with RNC CAD/CAM complete crowns placed with self-adhesive cement. All restoration designs survived the normal range of masticatory forces. Failure mode tended to be more favorable with the 2-mm buildup or no buildup (endocrown).

Metabolic enrichment of omega-3 polyunsaturated fatty acids does not reduce the onset of idiopathic knee osteoarthritis in mice

OBJECTIVE

We evaluated the effect of a reduction in the systemic ratio of n-6:n-3 polyunsaturated fatty acids (PUFAs) on changes in inflammation, glucose metabolism, and the idiopathic development of knee osteoarthritis (OA) in mice. We hypothesized that a lower ratio of n-6:n-3 PUFAs would protect against OA markers in cartilage and synovium, but not bone.

DESIGN

Male and female fat-1 transgenic mice (Fat-1), which convert dietary n-6 to n-3 PUFAs endogenously, and their wild-type (WT) littermates were fed an n-6 PUFA enriched diet for 9-14 months. The effect of gender and genotype on serum PUFAs, interleukin (IL)-6, tumor necrosis factor (TNF)-α, and glucose tolerance was tested by 2-factor analysis of variance (ANOVA). Cortical and trabecular subchondral bone changes were documented by micro-focal computed tomography (CT), and knee OA was assessed by semi-quantitative histomorphometry grading.

RESULTS

The n-6:n-3 ratio was reduced 12-fold and 7-fold in male and female Fat-1 mice, respectively, compared to WT littermates. IL-6 and TNF-α levels were reduced modestly in Fat-1 mice. However, these systemic changes did not reduce osteophyte development, synovial hyperplasia, or cartilage degeneration. Also the fat-1 transgene did not alter subchondral cortical or trabecular bone morphology or bone mineral density.

CONCLUSIONS

Reducing the systemic n-6:n-3 ratio does not slow idiopathic changes in cartilage, synovium, or bone associated with early-stage knee OA in mice. The anti-inflammatory and anti-catabolic effects of n-3 PUFAs previously reported for cartilage may be more evident at later stages of disease or in post-traumatic and other inflammatory models of OA.

Last-recorded P2Y12 reaction units value is strongly associated with thromboembolic and hemorrhagic complications occurring up to 6 months after treatment in patients with cerebral aneurysms treated with the pipeline embolization device

BACKGROUND AND PURPOSE

A recent study identified a preprocedural P2Y12 reaction units value of <60 or >240 as a strong independent predictor of perioperative thromboembolic and hemorrhagic complications after treatment of cerebral aneurysms with the Pipeline Embolization Device. This study aimed to determine whether a last-recorded P2Y12 reaction units value of <60 or >240 predicts thromboembolic and hemorrhagic complications up to 6 months after treatment of cerebral aneurysms with the Pipeline Embolization Device in the same patient cohort.

MATERIALS AND METHODS

We recorded patient and aneurysm characteristics, P2Y12 receptor antagonist administered, P2Y12 reaction units value with VerifyNow, procedural variables, and thromboembolic and hemorrhagic complications up to 6 months after Pipeline Embolization Device procedures at our institution during an 8-month period. Complications causing a permanent disabling neurologic deficit or death were considered major. Multivariate regression analysis was performed to identify independent predictors of thromboembolic and hemorrhagic complications.

RESULTS

Forty-four patients underwent 48 Pipeline Embolization Device procedures at our institution during the study period. There were 11 thromboembolic and hemorrhagic complications up to 6 months after treatment in our cohort (22.9%), 5 of which were major (10.4%). A last-recorded P2Y12 reaction units value of <60 or >240 was the only independent predictor of all (P = .002) and major (P = .03) thromboembolic and hemorrhagic complications in our cohort. Most patients (71%) required, on average, 2 adjustments to the dose or type of P2Y12 receptor antagonist to remain within the 60-240 target P2Y12 reaction units range.

CONCLUSIONS

In our cohort, a last-recorded P2Y12 reaction units value of <60 or >240 was the only independent predictor of all and major thromboembolic and hemorrhagic complications up to 6 months after Pipeline Embolization Device procedures.

Did life originate from a global chemical reactor?

Many decades of experimental and theoretical research on the origin of life have yielded important discoveries regarding the chemical and physical conditions under which organic compounds can be synthesized and polymerized. However, such conditions often seem mutually exclusive, because they are rarely encountered in a single environmental setting. As such, no convincing models explain how living cells formed from abiotic constituents. Here, we propose a new approach that considers the origin of life within the global context of the Hadean Earth. We review previous ideas and synthesize them in four central hypotheses: (i) Multiple microenvironments contributed to the building blocks of life, and these niches were not necessarily inhabitable by the first organisms; (ii) Mineral catalysts were the backbone of prebiotic reaction networks that led to modern metabolism; (iii) Multiple local and global transport processes were essential for linking reactions occurring in separate locations; (iv) Global diversity and local selection of reactants and products provided mechanisms for the generation of most of the diverse building blocks necessary for life. We conclude that no single environmental setting can offer enough chemical and physical diversity for life to originate. Instead, any plausible model for the origin of life must acknowledge the geological complexity and diversity of the Hadean Earth. Future research may therefore benefit from identifying further linkages between organic precursors, minerals, and fluids in various environmental contexts.

Diagnostic yield of catheter angiography in patients with subarachnoid hemorrhage and negative initial noninvasive neurovascular examinations

BACKGROUND AND PURPOSE

The yield of DSA in patients with SAH and negative initial noninvasive neurovascular examinations (CTA or MRA) is not well-understood. This study aimed to determine the yield of DSA for the detection of causative vascular lesions in this clinical scenario.

MATERIALS AND METHODS

We examined the yield of DSA for the detection of causative vascular lesions in a cohort of patients presenting to our institution with SAH and negative initial noninvasive neurovascular examinations during a 5-year period. Two experienced neuroradiologists independently evaluated the NCCT to determine the SAH pattern (diffuse, perimesencephalic, or peripheral sulcal) and the catheter angiograms to assess the presence of a causative vascular lesion.

RESULTS

Fifty-five patients were included in the study, with a mean age of 58.2 years (median, 58 years; range, 25-88 years). Twenty-eight patients were men (50.9%), and 27 were women (49.1%). The initial noninvasive examination was a CTA in 47 patients (85.5%) and an MRA in 8 patients (14.5%). Thirty-three patients had diffuse SAH (60%); 11, perimesencephalic SAH (20%); and 11, peripheral sulcal SAH (20%). DSA demonstrated a causative vascular lesion in 6 patients (10.9%), 5 of whom had diffuse SAH (yield of 15.2%) and 1 of whom had peripheral sulcal SAH (yield of 9.1%). No causative vascular lesions were found in patients with perimesencephalic SAH.

CONCLUSIONS

DSA is a valuable tool in the evaluation of patients with diffuse and peripheral sulcal SAH who have negative initial noninvasive neurovascular examinations, demonstrating a causative vascular lesion in 15.2% and 9.1% of patients, respectively.

271 THE EFFECT OF TEMPERATURE ON HUMAN TESTICULAR TISSUE TO OPTIMIZE THE IN VITRO MATURATION OF PRE-FREEZE MOTILITY

The development of intracytoplasmic sperm injection has made the use of testicular sperm a viable option for infertile men with obstructive and nonobstructive azoospermia. Over the past decade, testicular biopsies have been handled and processed using a variety of different methods. Whole biopsy pieces can be effectively cryopreserved in a 10% glycerol diluent (Schiewe et al. 1997 67, S115 abst); however, the ability to find viable, motile sperm post-thaw is improved when prefreeze motility exists. The purpose of this study was to comparatively document in vitro sperm motility enhancement over time at different temperatures, and to prove that an intermediate temperature (28 to 30°C) would optimize sperm longevity for up to 1 week. In this study, 10 men with obstructive azoospermia underwent a surgical, open testicular biopsy procedure. Each biopsy was placed in HEPES buffered-human tubal fluid (mHTF) medium supplemented with 5% human serum albumin (HSA; Irvine Sci., Santa Ana, CA, USA) and transported to the laboratory at room temperature. Each testis biopsy (TBx) was dissected into 8 equal pieces (approximately 2 × 2 × 1 mm). Five intact pieces of TBx were cryopreserved in separate cryovials for future use. The remaining TBx tissue was subdivided into 1 of 3 temperature treatment groups (24, 30, or 37°C) for extended IVM. The 30°C incubation condition was achieved by placing the dish(es) in a Styrofoam box placed on a 37°C warming plate. Each TBx was placed into a separate 100 × 35 mm Falcon dish in 150-μL droplets of mHTF under oil and shredded by needle dissection to disperse the contents of the seminiferous tubules. Reminant tissue was placed into another droplet for additional dissection, as needed. Sperm were analyzed for motility (graded as Type I = twitching, II = undulating, III = slow progression, and IV = rapid progression) at 0, 24, 96, and 144 h without replacing the IVM medium. The percentage increase in motility, compared with 0 h, was statistically contrasted across temperature treatments by chi-squared analysis. Testicular sperm motility ranged from 5 to 25% at 0 h and increased in all groups at 24 h. There was no difference in total motility at 24 h, but progressive motility was higher (P < 0.05) at 37°C compared with 24°C. Significant differences (P < 0.05) were observed in total percentage of motility/percentage of progressive motility at 96 h with treatment differences (*) being 30°C (66%*/44%*) > 24°C (42%*/14%) > 37°C (18%*/10%). This statistical trend continued at 144 h with 30°C (42%*/23%*) > 24°C (24%*/8%) > 37°C (9%*/5%). During this study, a viable pregnancy was achieved using a 30°C sample 8 days post biopsy, exceeding 2 previous healthy triplet pregnancies, which were successful using 4-day-old TBx specimens in 1996 and 2004. This study confirms that an intermediate IVM temperature of 30°C is optimal to enhance TBx cryopreservation, which in our laboratory is generally performed at 24 to 72 h of IVM. Our routine pregnancy success in applying ICSI with IVM, thawed TBx sperm discounts the concern some individuals express regarding DNA fragmentation of sperm over time.

Use of conventional ECG electrodes for depth of anaesthesia monitoring using the cerebral state index: a clinical study in day surgery

BACKGROUND

The cost-benefit relationship for depth of anaesthesia monitors is complicated by the high cost of specially designed EEG electrodes. The cerebral state index (CSI) monitor will accept regular ECG electrodes with snap connectors. The purpose of this study was to determine if generic ECG electrodes could replace the more expensive proprietary EEG electrodes for the CSI monitor.

METHODS

Two identical cerebral state monitors were used simultaneously during sevoflurane anaesthesia for knee arthroscopy in 14 ASA I-II patients. One monitor used proprietary (Danmeter) EEG electrodes and the other used ECG electrodes (3M Red Dot Diagnostic ECG Electrodes). Paired CSI values were recorded every other minute. Anaesthetic depth was titrated clinically. Sedation depth was scored according to the Observer's Assessment of Alertness/Sedation (OAAS) scale.

RESULTS

The agreement between the two measures was found to be high, mean difference--0.23, and the overall repeatability mean bias was 6.6 and 153/163 pairs (94%) were located within the 95% limits of agreement. No major difference was noted in impedance, noise, or artifacts. A large overlap in CSI was noted for each level of the OAAS scale; patients with CSI values as low as 40-50 responded whereas patients not responding to surgical stimulation had CSI values as high as 75. The direct cost of disposables decreased from 4euro to 0.50euro per patient by using ordinary ECG electrodes.

CONCLUSIONS

Switching from proprietary EEG electrodes to ordinary generic ECG electrodes maintains the same accuracy at about a 10th of the cost when measuring CSI during day surgery with sevoflurane anaesthesia.

The effects of fresh gas flow on the amount of sevoflurane vaporized during 1 minimum alveolar concentration anaesthesia for day surgery: a clinical study

BACKGROUND

Even small costs per case can become economically significant in high volume day surgical units. While general anaesthesia with higher fresh gas flow rates has technical advantages, they result in higher costs. The aim of the present study was to evaluate drug consumption and direct costs related to variations in the fresh gas flow and use of nitrous oxide at a 1 minimum alveolar concentration (MAC) sevoflurane end-tidal anaesthesia for day surgery.

METHODS

Thirty-two ASA I-II patients undergoing elective day surgery under general anaesthesia [14 (10-21) min] were studied. Induction was with propofol and fentanyl 100 microg. After laryngeal mask airway placement, patients were randomized to one of four different fresh gas flows: 1 or 2 l/min oxygen in air (50% oxygen), 3 l/min (33% oxygen), or 3 l/min oxygen in nitrous oxide (33% oxygen). Anaesthesia was maintained at 1 MAC. The vaporizer was weighed before and after each procedure. The primary study variable was the sevoflurane utilization per minute.

RESULTS

Sevoflurane utilization increased with increasing fresh gas flow for oxygen in air (r2 = 0.89). The nitrous oxide in oxygen group had the lowest sevoflurane utilization, even compared with the lowest oxygen in air group (0.36 vs. 0.48 g/min).

CONCLUSION

Sevoflurane utilization during 1 MAC anaesthesia increases linearly with fresh gas flow and is still higher than when nitrous oxide is used even with very low fresh gas flow rates. Direct inhaled anaesthesia-related costs are consequently 20% higher than when nitrous oxide is used, even for the lowest oxygen in air fresh gas flows.

Cerebral state index: comparison between pairwise registrations from the left and the right sides of the brain

BACKGROUND

Lateralization of cerebral blood flow and EEG activity is known to vary during cognition, sleep and waking. In spite of this, electrode placement for the cerebral state index (CSI) monitor is not specified to a particular side of the brain. This study is designed to determine if pairwise registrations differ for CSI measured simultaneously from the left or right sides of the brain.

METHODS

In total, 25 ASA I-II patients undergoing elective day surgery under general anaesthesia were recruited. Pairwise recordings were made every minute from two CSI monitors (Cerebral State Monitor, Danmeter A/S; Odense, Denmark) connected to the left and the right side of the head. Sedation was graded according to the observer's assessment of alertness/sedation rating scale and correlated with CSI.

RESULTS

A large overlap of indices, of similar magnitude, for each side of the brain was seen between different levels of sedation. The agreement between pairwise registrations was high, correlation between the 584 CSI pairs of recordings left/right was r(2)=0.92.

CONCLUSIONS

Despite known lateralization of the EEC, this study found a very high correlation in CSI derived simultaneously from the left and right sides of the brain by two independent monitors.

Cerebral state index response to incision: a clinical study in day-surgical patients

BACKGROUND

Inadequate anaesthesia, with somatic/autonomic response or awareness, is often revealed at intubation and surgical incision. Anaesthetic depth monitors should be able to prevent this risk. This explorative study examined the ability of the cerebral state monitor to predict autonomic/somatic responses to incision.

METHODS

Forty-two ASA I-II day-surgical patients [19 men and 23 females; mean age 52 (29-79) years, mean weight 77 (50-118) kg] were induced clinically with fentanyl/propofol with sevoflurane after placement of the laryngeal mask airway. The cerebral state index (CSI) was blindly recorded 4 min prior to and 4 min after incision.

RESULTS

During the 4 min prior to incision, the mean CSI was 45 (16-62) and increased by 9 (-13-40) when the mean value for the first 4 min after incision was subtracted from the value prior to incision, corresponding to a relative change of 21% (-21-118). The change in CSI did not show any consistent relation to the value before incision. Five patients showed minor movements after incision and six patients had > 25% increase in blood pressure. Neither CSI nor the change in index differed between patients who did or did not respond somatically or autonomically to incision. The last CSI value just prior to incision was 44 for non-responders and 40 and 42 for somatic and autonomic responders, respectively.

CONCLUSION

The CSI in the majority of patients was within acceptable ranges during clinically adjusted anaesthesia prior to incision but seems not to be able to reliably predict an autonomic or somatic response to incision.

Desflurane vs. sevoflurane as the main inhaled anaesthetic for spontaneous breathing via a laryngeal mask for varicose vein day surgery: a prospective randomized study

BACKGROUND

Sevoflurane has become widely used in day surgery; however, desflurane may be a valuable alternative even in this setting. This study compares emergence from anaesthesia for day surgery with spontaneous breathing using either desflurane or sevoflurane.

METHODS

This prospective, randomized, single-blinded study examined 70 ASA III patients undergoing elective ambulatory varicose vein surgery. Primary endpoint was emergence time (cessation of anaesthetic gas to communicating). Secondary endpoints included post-operative pain, nausea, time to discharge, and patient satisfaction. Patients were anaesthetized according to a standardized protocol including multimodal analgesia and antiemetic therapy and were randomized to receive sevoflurane or desflurane as the main anaesthetic while breathing spontaneously through a laryngeal mask airway. Fresh gas flow was oxygen in air 1 : 2 l/min.

RESULTS

Intra-operative anaesthesia was uneventful apart from airway irritation observed in 5/35 desflurane and 1/35 sevoflurane patients. Emergence was 25-40% faster in patients anaesthetized with desflurane. Pain and post-operative nausea and vomiting (PONV) were equally infrequent in both groups. Overall, patient satisfaction was high with no difference between the groups.

CONCLUSION

Desflurane is associated with a faster emergence with no differences during the post-operative course except a somewhat higher incidence of airway irritation.

Cerebral state monitor, a new small handheld EEG monitor for determining depth of anaesthesia

BACKGROUND AND OBJECTIVE

The cerebral state index (CSI) derived from a new small handheld electroencephalogram monitor was studied during routine day surgical anaesthesia titrated according to the bispectral index (BIS). The objective was to determine the degree of agreement between the two monitors.

METHODS

Anaesthesia was induced with propofol and fentanyl (0.1 mg) in 38 patients undergoing general anaesthesia for routine day-surgery. Maintenance anaesthesia (sevoflurane (20/38), desflurane (10/38) or propofol (8/38)) titrated by BIS XP (Aspect Medical, Natwick, MA, USA) and BIS and CSI (cerebral State Monitor, Danmeter; Odense, Denmark) index values were recorded every minute. No patient received muscle relaxation. Observer's Assessment of Alertness/Sedation rating scale was used to assess level of sedation.

RESULTS

Pair-wise recordings (914) of CSI and BIS were collected. The indices showed similar pattern and decreased with increasing level of sedation, however with large ranges for each level of sedation. Median indices were similar during surgery (BIS: 50 (14-89); CSI: 51 (7-88)) and both indices increased (P 20% from BIS-index in 24% of readings, and on rare occasions CSI indices deviated >100% from the BIS reading. When BIS < 40, CSI decreased slower than BIS and with wider spreading.

CONCLUSIONS

When used for day-surgery anaesthesia without muscle relaxation, CSI and BIS show similar patterns and numerical values but with the incidence of occasionally large discrepancies between pair-wise readings. Which monitor is the more dependable remains to be established and cannot be implied from this initial explorative study.