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Purpose –This paper is the second of a two part series which offers new theoretical and empirical insights investigating the rates structures appropriate for exhaustible resources with a particular emphasis on urban land, based upon the differentiation of strong- and weak-form sustainability concepts constrained by the objectives of the sustainable criterion of Daly and Cobb (1994). The integration of the concepts and objectives allow the theoretical formulation of discount and capitalization rates that can be empirically tested. This empirical application employs data from 12 diverse national economies. The paper aims to discuss these issues. Design/methodology/approach – The paper integrates the concepts of discount rate development for environmental and long-term assets and discounted utility analysis to the policy concerns associated with the valuation of public and sustainable resources. The new approach empirically shows the diverse issues of competing sustainable objectives across nations. Findings – The potential and degree of strong-form or weak-form sustainability application in each nation enabled the identification as to whether alternative capital as defined by the modified Ramsey model used per nation, or the marginal rate of resource return as defined by strong form objective of a constant natural resource endowment, can identify which form of capital becomes the major constraint on the resource valuation and allocation decision appropriate within each nation. The findings showed constraints on nation resource endowments relative to population needs and the culture preferences endemic across nations. Originality/value – The findings serve as a basis for future research on the optimal levels of sustainable development appropriate for different nations, the impactions of the timing and level of capital re-switching associated with the application of strong- or weak-form sustainability and the develop of rate and risk measures that can assist in the consideration of sustainable resource as a distinct asset class. [ABSTRACT FROM AUTHOR]

This study assessed if wearing a heart rate monitor influenced student activity levels in elementary physical education. Data were analyzed for 4 students using an alternating treatment design to assess differential effects between accelerometer activity counts obtained from students when wearing the heart rate monitor and when they were not wearing the monitor. Results show that (a) there was no difference in activity counts between the 2 conditions, (b) boys had higher means than girls, and (c) the variance between more and less active boys was greater than the variance among the girls. [ABSTRACT FROM AUTHOR]

Abstract Background Care of the polytrauma patient does not end in the operating room or resuscitation bay. The patient presenting to the intensive care unit following initial resuscitation and damage control surgery may be far from stable with ongoing hemorrhage, resuscitation needs, and injuries still requiring definitive repair. The intensive care physician must understand the respiratory, cardiovascular, metabolic, and immunologic consequences of trauma resuscitation and massive transfusion in order to evaluate and adjust the ongoing resuscitative needs of the patient and address potential complications. In this review, we address ongoing resuscitation in the intensive care unit along with potential complications in the trauma patient after initial resuscitation. Complications such as abdominal compartment syndrome, transfusion related patterns of acute lung injury and metabolic consequences subsequent to post-trauma resuscitation are presented. Methods A non-systematic literature search was conducted using PubMed and the Cochrane Database of Systematic Reviews up to May 2012. Results and conclusion Polytrauma patients with severe shock from hemorrhage and massive tissue injury present major challenges for management and resuscitation in the intensive care setting. Many of the current recommendations for “damage control resuscitation” including the use of fixed ratios in the treatment of trauma induced coagulopathy remain controversial. A lack of large, randomized, controlled trials leaves most recommendations at the level of consensus, expert opinion. Ongoing trials and improvements in monitoring and resuscitation technologies will further influence how we manage these complex and challenging patients.

Background The impact of the coronavirus disease 2019 (COVID-19) pandemic substantially altered operations at hospitals that support graduate medical education. We examined the impact of the pandemic on an anesthesiology training program with respect to overall case volume, subspecialty exposure, procedural skill experience, and approaches to airway management. Methods Data for this single center, retrospective cohort study came from an Institutional Review Board approved repository for clinical data. Date ranges were divided into the following phases in 2020: Pre-Pandemic (PP), Early Pandemic (EP), Recovery 1 (R1), and Recovery 2 (R2). All periods were compared to the same period from 2019 for case volume, anesthesia provider type, trainee exposure to Accreditation Council for Graduate Medical Education (ACGME) index case categories, airway technique, and patient variables. Results 15,087 cases were identified, with 5,598 (37.6%) in the PP phase, 1,570 (10.5%) in the EP phase, 1,451 (9.7%) in the R1 phase, and 6,269 (42.1%) in the R2 phase. There was a significant reduction in case volume during the EP phase compared to the corresponding period in 2019 (-55.3%; P < .001) that improved but did not return to baseline by the R2 phase (-17.6%; P < .001). ACGME required minimum cases were reduced during the EP phase compared to 2019 data for pediatric cases (age < 12 y, -72.1%; P < .001 and age < 3 y, -53.5%; P < .006) and cardiopulmonary bypass cases (52.3%, P < .003). Surgical subspecialty case volumes were significantly reduced in the EP phase except for transplant surgery. By the R2 phase, all subspecialty volumes had recovered except for plastic surgery (14.9 vs. 10.5 cases/week; P < .006) and surgical endoscopy (59.2 vs. 40 cases/week; P < .001). Use of video laryngoscopy (VL) and rapid sequence induction and intubation (RSII) also increased from the PP to the EP phase (24.6 vs. 79.6%; P < .001 and 10.3 vs. 52.3%; P < .001, respectively) and remained elevated into the R2 phase (35.2%; P < 0.001 and 23.1%; P < .001, respectively). Conclusions The COVID-19 pandemic produced significant changes in surgical case exposure for a relatively short period. The impact was short-lived, with sufficient remaining time to meet the annual ACGME program minimum case requirements and procedural experiences. The longer-term impact may be a shift towards the increased use of VL and RSII, which became more prevalent during the early phase of the pandemic., Competing Interests: The authors have declared financial relationships, which are detailed in the next section., (Copyright © 2023, Grissom et al.)

Background: Intracranial hypertension (ICH) and hyperthermia are common after traumatic brain injury (TBI) and associated with worse neurological outcomes. This study sets out to determine the combined power of temperature and intracranial pressure (ICP) for predicting neurologic outcomes and prolonged length of stay (LOS) following severe TBI., Methods: High resolution (every 6 seconds) temperature and ICP data were collected in adults with severe TBI from 2008-2010. Temperatures were plotted against concurrent ICP and divided based on breakpoints (Temperature: <36, 36-38.5 or >38.5 °C, ICP: <20, 20-30 or >30 mmHg). The percentage of time spent in each section, as well as several pooled unfavourable conditions (hyperthermia ± ICH), were then evaluated for predictive value for ICU-LOS > 7 days and short-term (<6 months) vs. long-term (>6 months) dichotomized neurologic outcomes., Results: Fifty patients were included for analysis with severe TBI. Evaluation of the area under the operating receiver curve (AUC) showed significant periods of fever and high ICP (<30 mmHg) had a strong association with poor long-term neurological outcomes (Day 3, AUC = 0.71, p = 0.04) and were higher than either condition alone. ICU-LOS > 7 days was increased when hyperthermia and/or ICH remained uncontrolled by Day 5 (AUC = 0.82, p = 0.02)., Summary: Hyperthermia combined with ICH were shown to be significant prognostic indicators of future poor neurologic outcomes in patients with severe traumatic brain injury.

Objective: This study sought to determine whether continuous gastric suctioning influences esophageal temperature measurements., Methods: This study evaluated 21 patients scheduled for extremity or lower abdominal surgery. After induction of general endotracheal anesthesia, an orogastric tube, and esophageal and nasopharyngeal temperature probes were placed in functional positions. Baseline esophageal (Tes) and nasopharyngeal (Tnas) temperatures were recorded and the orogastric tube was placed on continuous suction. After the first 11 patients (Group I) were studied, 10 additional patients (Group II) were studied with more frequent data collection to improve the time resolution of temperature changes. Temperatures were recorded for patients in Group I at 2 and 10 min with suctioning and 10 min after cessation of suctioning. In Group II, temperatures were recorded at 1, 2, 5 and 10 min with suctioning and 10 min after cessation of suctioning. Analysis of data was performed using repeated measures analysis of variance and paired t-tests with the Bonferroni correction., Results: In Group I, Tes decreased significantly from 35.9 +/- 0.2 degrees C (mean +/- SE) to 35.1 +/- 0.4 degrees C at 2 min and 34.8 +/- 0.3 degrees C at 10 min of suctioning (p < 0.01). Ten minutes after cessation of suctioning, Tes was not significantly different from the baseline measurement. Tnas did not change significantly over the 20 min observation period. In Group II, Tes continually decreased from 36.2 +/- 0.1 degrees C to 34.8 +/- 0.3 degrees C after 10 min of suctioning (p < 0.006) and returned to near baseline 10 min after cessation of suctioning. There was no significant change in Tnas over the 20 min observation period., Conclusion: We conclude that continuous gastric suctioning decreases esophageal temperature measurements. This phenomenon should be recognized as an artifactual change in esophageal temperature and not a reflection of core temperature.

Objectives: a) To determine the response of endotoxin-exposed vascular smooth muscle to exogenous vasoconstrictors during concomitant exposure to an inhaled anesthetic (halothane); and b) to determine if excess nitric oxide production is responsible for any altered response., Design: In vitro, prospective, repeated-measures, dose-response study., Setting: University/medical school experimental physiology laboratory., Subjects: Adult male Sprague-Dawley rats, whose aortae were studied in an in vitro preparation., Interventions: Thoracic aortae were excised from anesthetized animals and cut into 3-mm rings. After incubation in aerated organ baths containing a modified essential medium with or without Escherichia coli lipopolysaccharide (100 micrograms/mL) at 37 degrees C for 5 hrs, the rings were removed and suspended in separate baths for isometric tension recording. Phenylephrine dose-response data (10(-10) to 10(-5) M) were determined for lipopolysaccharide- and nonlipopolysaccharide-treated rings. After washout and equilibration, two vessels (one each lipopolysaccharide- and nonlipopolysaccharide-treated) were additionally exposed to 2% halothane and phenylephrine dose-response determinations were repeated for all vessels. This procedure was repeated for 1% halothane in a separate experiment. In some experiments, the nitric oxide synthase inhibitor, N omega-nitro-L-arginine (3 x 10(-4) M), was added to the bath after the washout from the second phenylephrine dose-response determination. Then, a third phenylephrine dose-response determination was performed, with and without 2% halothane., Measurements and Main Results: Dose-response curves were evaluated using a logistic regression analysis. In addition, absolute and percentage changes in tension were compared between the first and second contractions. Exposure to lipopolysaccharide resulted in a decrease in the maximum tension from 2.07 +/- 0.03 (controls) to 1.24 +/- 0.04 g/mg of vessel dry weight and an increase in the dose at which the contraction is 50% of maximum (ED50) from 3.78 x 10(-8) to 2.05 x 10(-7) M (p < .05). Exposure to 2% halothane produced significant reductions in the maximum tensions in both groups. The lipopolysaccharide-treated vessels showed not only a proportionately larger decrease (-51 +/- 5% vs. -18 +/- 2% in the control plus halothane group), but also a significantly greater absolute decrease (0.59 +/- 0.09 vs. 0.34 +/- 0.04 g/mg in the control plus halothane group). The addition of 1% halothane produced less pronounced decreases in tension, with only an additive effect in the lipopolysaccharide-treated vessels. The addition of N omega-nitro-L-arginine resulted in a reversal of the lipopolysaccharide-induced decrease in tension. However, 2% halothane still had a significantly greater effect on the lipopolysaccharide-exposed rings., Conclusions: Exposure of rat aortic rings to lipopolysaccharide in vitro decreased the contractile response to phenylephrine. The addition of 2% halothane resulted in a more than additive decrease in tension in the lipopolysaccharide-treated vessels. Patients in septic or endotoxic shock are sensitive to most anesthetic regimens, and some of this sensitivity may be due to an altered vasoconstrictive response induced by lipopolysaccharide exposure. The inability of nitric oxide synthase inhibition to reverse this response completely suggests that induction of nitric oxide synthase and increased production of nitric oxide are not solely responsible for this finding.

We evaluated the effects of anesthetics on neurologic outcome in a model of recoverable experimental spinal cord injury (SCI). Adult rats were implanted with various sizes of hygroscopic plastic material at the T12 spinal level to determine the dimensions that would produce a progressive neurologic deficit from which recovery could occur. Neurologic evaluation was conducted on an inclined plane, noting the maximum angle at which an animal was able to maintain orientation perpendicular to the longitudinal midline. Scores were statistically modeled for each group to develop profiles of neurologic deficits. Rats were subjected to a 4-h exposure to isoflurane, fentanyl/nitrous oxide, or ketamine 7 or 8 days postimplantation. Neurologic outcomes were compared to a SCI reference group which received no postimplant anesthesia. An animal weight/desiccated implant volume (Wa/Vi) ratio of 53 to 73 g/mm3 produced postimplant neurologic deficits which deteriorated to near maximum within 3 days, followed by a gradual improvement beginning at Day 8 and returning to near normal between 21 and 25 days. Final outcome was based on modeled ramp scores for each group and reported in degrees +/- SD: reference, 71.2 +/- 1.1; fentanyl/N2O, 70.4 +/- 0.3; isoflurane, 72.6 +/- 1.1; and ketamine, 64.9 +/- 0.6. The fentanyl group attained maximum recovery first (P > 0.05) but did not recover to a level different on the average from the reference group. The ketamine group demonstrated a poorer (P > 0.05) recovery level relative to the other anesthetic protocols.

Objective: To compare propofol, methohexital, and midazolam administered as titrated infusions for sedation during electrical cardioversion., Design: A prospective, randomized, single-blind comparative study., Setting: Coronary care unit in a military teaching hospital., Patients: Thirty adult patients with atrial fibrillation, atrial flutter, or paroxysmal supraventricular tachycardia. Each patient required electrical cardioversion. Patients were randomized to receive one of the three study drugs. Ten patients composed one drug group., Measurements and Main Results: Demographic variables were similar between groups. Patients were randomized to receive propofol (10 mg/mL), methohexital (5 mg/mL), or midazolam (0.5 mg/mL) administered at 10 mL/min until the patients failed to follow verbal commands and demonstrated a degradation of the lid response to stimulation. Dose requirements (mean +/- SD) were propofol 1.69 +/- 0.46 mg/kg, methohexital 1.07 +/- 0.34 mg/kg, and midazolam 0.16 +/- 0.06 mg/kg. Hemodynamic assessment at baseline, after induction, after cardioversion, and at recovery demonstrated no difference in mean arterial pressure between the three groups. The time to awakening was significantly prolonged in the group that received midazolam (33 +/- 11 mins, p < .05) as compared with the times of the groups that received propofol (11 +/- 4 mins) and methohexital (9 +/- 3 min). Side-effects were similar between groups, with the exception of an increase in pain on injection with propofol and an increased frequency of confusion in those patients receiving midazolam. Recall of the electrical discharges at one hour after the procedure occurred in two patients in the propofol group. In both cases, there were technical problems which caused the duration of the procedure to extend into the anticipated recovery period. Unit dose costs at our institution for a 70-kg patient are: methohexitol, $3.14 (500-mg bottle); medazolam, $14.88 (5-mg vials x 3); and propofol, $6.60 (200-mg ampule)., Conclusions: All three drugs are acceptable choices for use during elective direct-current cardioversion. Titration of the agent results in a total drug dose which is usually less than the typical induction dose. There were no significant differences in the hemodynamic actions of these drugs at any time interval. Both propofol and methohexital proved superior in their ability to provide a more rapid anesthetic onset and recovery as compared with midazolam. Propofol offers the advantage of requiring no premixing or dilution, and it is not a controlled substance, although it does result in more pain on injection.

Usher syndrome is an autosomal recessive disorder characterized by severe hearing loss or deafness and retinitis pigmentosa. Eleven families with 25 affected members were studied. The test battery included genetic studies, clinical examination, audiological, ophthalmologic, and otoneurological tests, and magnetic resonance imaging. Sixteen affected persons had profound hearing loss or were considered anacusic, with absent bilateral vestibular responses. These patients had varying degrees of retinitis pigmentosa. These 16 patients were considered to have type I Usher syndrome. Nine persons were diagnosed as Usher type II with a moderate to profound hearing loss, normal vestibular function, and retinitis pigmentosa of varying degree. Magnetic resonance imaging was normal in all cases. Otoneurological tests indicated no central nervous system disturbances. The conclusion is that hearing loss and balance problems in Usher syndrome are due to inner ear damage with no evidence of central nervous system disturbances. Furthermore, the ataxia seen in Usher type I is due to a combination of retinitis pigmentosa and bilateral peripheral vestibular deficiency.

Abdominal pregnancy is a rare event and preoperative diagnosis may be difficult. Recently, sonographic examination and magnetic resonance imaging have proved helpful in the preoperative diagnosis in a patient who presented with advanced abdominal pregnancy after tubal sterilization. As well, ultrasound was of benefit in the follow-up of placental involution after delivery.

The issue of genetic heterogeneity is a critical problem in the localization of the gene(s) for Usher syndrome. Based on the data obtained on families studied to date, the differences between type I and type II Usher syndrome appear quite distinct with regard to auditory and vestibular function. Although the majority of families can be confidently diagnosed as typical type I or type II, clinical investigations revealed four families with findings that did not fit into either of the two more common subtypes. These findings emphasize the critical importance of an in-depth clinical analysis concomitant with the linkage investigation to assure accurate subtyping of Usher syndrome. Based on an analysis of only those families with definite type I or type II Usher syndrome, approximately 17% of the genome can be excluded as a potential site of the gene for type I, and 14% can be excluded as the site for the type II gene. This study will continue until the Usher gene(s) is successfully localized.