Improved clinical trial race/ethnicity reporting and updated inclusion profile, 2017-2022: A New Jersey snapshot

Background

Diverse representation in clinical trials is an important goal in the testing of a medical, diagnostic, or therapeutic intervention. To date, the desired level of trial equity and inclusivity has been unevenly achieved.

Methods

Employing the US National Library of Medicine's Clinicaltrials.gov registry, we examined 481 clinical trials conducted - at least in part - in the state of New Jersey. These trials were initiated after the FDA-mandated Common Rule changes, i.e., between January 2017 and October 2022, were enacted, and had their results posted. We analyzed sex/race/ethnicity reporting as well as applicable enrollment. Using meta-analysis, we estimated group participation proportions of a subset of the 481 identified trials; specifically, the 229 studies that were conducted solely within the US (i.e., without international sites) and compared them to US census data.

Findings

Within the 481 clinical trials analyzed, over 97% reported on the race and/or ethnicity of their enrollees; all included information on sex. Reporting was not affected by funding source or therapeutic area. Based on the 229 solely US-based studies, the participants overall were 76.7% White; 14.1% Black; 2.7% Asian; and 15% Hispanic. Inclusion of Black participants did not differ from the 2020 US census data; in contrast, the levels of Asian and Hispanic participation were below the corresponding census percentages.

Interpretation

The past five years have seen an overall uptick in the equity of race/ethnicity reporting and inclusivity of clinical trials, as compared to previously reported data, presaging the potential acquisition of ever more powerful and meaningful results of such interventional studies going forward.

Funding

Support for this study comes from the Hackensack Meridian Health Research Institute and the Hackensack Meridian School of Medicine.

Research in context

Evidence before this studyClinical trials are a critical part of determining whether or not a medical (drug/device/biologic) or socio-behavioral intervention is safe and truly effective. Through their use, scientific understanding is advanced and, ideally, human health is improved. To gain the most impactful information from a clinical trial, it should be sufficiently representative, that is, should enroll an adequate number of participants, and include a diverse population. Without such inclusion, the study is of only limited generalizability. Efforts are underway by funders, sites, and other stakeholders, to enhance reporting and promote inclusive enrollment. The extent to which such attempts are yielding results - at least for clinical trials in the state of New Jersey - is the focus of this data-driven analysis. The ClinicalTrials.gov registry database was carefully mined for the information contained in this report.Added value of this studyOur analysis of clinical trials initiated in the state of New Jersey and conducted there or elsewhere in the US reveals several positive trends. Our 5-year snapshot reveals that a very large percentage of trials report on race/ethnicity - and inclusivity is improving. While there is still some way to go to have the demographic numbers in these trials match US census values, our results suggest that recent efforts are having an effect.Implications of all the available evidenceFor myriad reasons, clinical trials have not enjoyed the public's universal trust over the years. In many ways, medicine moves at the speed of trust - without it, the promise of modern healthcare is brought into question. Clinical trials must include a commitment to diverse enrollment pools and equitable reporting under the law. Creating a legacy of trust - through greater inclusivity in clinical trials and more transparent reporting of results - will begin to heal the divide and engender faith in modern medicine and today's healthcare system. It would also allow for the desired far-reaching generalizability of results across patient populations. To better appreciate what needs to be done going forward, we must truly understand the state of clinical trials reporting and demographic inclusion. This report initiates such an analysis, by carefully documenting how New Jersey's clinical trials are performing. By virtue of its location (e.g., proximity to the cities of New York and Philadelphia) the state is part of a large biopharma cluster and healthcare nexus; it is critical that it performs well with respect to adopting/adhering to updated clinical trial guideline mandates. This report provides a glimpse - an important first look - into the state of clinical trials in New Jersey - from 2017 through 2022.

Does Utilizing IRIS, a Segmented Three-dimensional Model, Increase Surgical Precision During Robotic Partial Nephrectomy?

PURPOSE

Preservation of renal parenchyma is a major goal when performing a partial nephrectomy. IRIS anatomical visualization software generates a segmented 3D model, allowing improved visualization of the tumor and surrounding structures. We hypothesize that using IRIS intraoperatively during partial nephrectomy on complex tumors increases the precision of surgical procedures and therefore may result in more tissue preservation.

METHODS

We identified 74 non-IRIS and 19 IRIS patients who underwent partial nephrectomy, with nephrometry scores of 9, 10, and 11. Propensity scores were used to match 18 pairs of patients on nephrometry score, age, and tumor volume. Pre- and postoperative imaging (MRI/CT) was obtained. Volumes of the preoperative tumor and preoperative whole kidney were obtained to calculate predicted postoperative whole kidney volume and then compared to actual postoperative whole kidney volume.

RESULTS

Mean differences between predicted and actual postoperative whole kidney volumes were 19.2 cm3 (SD=20.2) and 32 cm3 (SD=16.1, P = .0074) for IRIS and non-IRIS groups, respectively. The mean improvement in precision for the IRIS procedure was 12.8 cm3 (95% confidence interval, 2.5 to Inf; P = .02). There was no significant change in mean glomerular filtration rate from baseline to 6 months postoperatively between IRIS and non-IRIS groups (-6.39, SD=15.8 vs -9.54, SD=13.3; P = .5). No significant differences in complication rates (0 vs 1, P = .2), worsening glomerular filtration rate staging (5 vs 4, P = 1), and >25% decrease in glomerular filtration rate (3 vs 4, P = 1) were found between IRIS and non-IRIS groups.

CONCLUSIONS

We demonstrated that using IRIS intraoperatively when performing partial nephrectomy on complex tumors is associated with improved surgical precision.

Function of arteries and veins in conditions of simulated cardiac arrest

Introduction: The study examined the behavior of vasculature in conditions of eliminated cardiac function using mathematical modeling. In addition, we addressed the question of whether the stretch-recoil capability of veins, at least in part accounts for the slower response to simulated cardiac arrest.

Methods: In the first set of computational experiments, blood flow and pressure patterns in veins and arteries during the first few seconds after cardiac arrest were assessed via a validated multi-scale mathematical model of the whole cardiovascular system, comprising cardiac dynamics, arterial and venous blood flow dynamics, and microcirculation. In the second set of experiments, the effects of stretch-recoil zones of venous vessels with different diameters and velocities on blood velocity and dynamic pressure analyzed using computational fluid dynamics (CFD) modeling.

Results: In the first set of experiments, measurement of changes in velocity, dynamic pressure, and fluid flow revealed that the venous system responded to cardiac arrest more slowly compared to the arteries. This disparity might be due to the intrinsic characteristics of the venous system, including stretch-recoil and elastic fiber composition. In the second set of experiments, we attempted to determine the role of the stretch-recoil capability of veins in the slower response to cardiac arrest. During the second set of experiments, we found that this recoil behavior increased dynamic pressure, velocity, and blood flow. The enhancement in dynamic pressure through combining the results from both experiments yielded a 15-40% increase in maximum dynamic pressure due to stretch-recoil, depending on vein diameter under normal conditions.

Conclusion: In the situation of cardiac arrest, the vein geometry changes continue, promoting smooth responses of the venous system. Moreover, the importance of such vein behavior in blood displacement may grow as the pressure on the venous side gradually decreases with time. Our experiments suggest that the driving force for venous return is the pressure difference that remains within the venous system after the energy coming from every ventricular systole spent to overcome the resistance created by arterial and capillary systems.

Axonal Conduction Velocity in CA1 Area of Hippocampus is Reduced in Mouse Models of Alzheimer's Disease

The timing of action potentials arrival at synaptic terminals partially determines integration of synaptic inputs and is important for information processing in the CNS. Therefore, axonal conduction velocity (VC) is a salient parameter, influencing the timing of synaptic inputs. Even small changes in VC may disrupt information coding in networks requiring accurate timing. We recorded compound action potentials in hippocampal slices to measure VC in three mouse models of Alzheimer's disease. We report an age-dependent reduction in VC in area CA1 in two amyloid-β precursor protein transgenic mouse models, line 41 and APP/PS1, and in a tauopathy model, rTg4510.

Enhanced striatopallidal gamma-aminobutyric acid (GABA)A receptor transmission in mouse models of huntington's disease

BACKGROUND

Huntington's disease (HD) is caused by a CAG repeat expansion in the huntingtin gene. This mutation leads to progressive dysfunction that is largely attributable to dysfunction of the striatum. The earliest signs of striatal pathology in HD are found in indirect pathway gamma-Aminobutyric acid (GABA)-ergic spiny projection neurons that innervate the external segment of the globus pallidus (GPe). What is less clear is whether the synaptic coupling of spiny projection neurons with GPe neurons changes in HD.

OBJECTIVES

The principal goal of this study was to determine whether striatopallidal synaptic transmission was altered in 2 mouse models of HD.

METHODS

Striatopallidal synaptic transmission was studied using electrophysiological and optogenetic approaches in ex vivo brain slices from 2 HD models: Q175 heterozygous (het) and R6/2 mice.

RESULTS

Striatopallidal synaptic transmission increased in strength with the progression of behavioral deficits in Q175 and R6/2 mice. The alteration in synaptic transmission was evident in both prototypical and arkypallidal GPe neurons. This change did not appear attributable to an increase in the probability of GABA release but, rather, to an enhancement in the postsynaptic response to GABA released at synaptic sites. This alteration significantly increased the ability of striatopallidal axon terminals to pause ongoing GPe activity.

CONCLUSIONS

In 2 mouse models of HD, striatopallidal synaptic transmission increased in parallel with the progression of behavioral deficits. This adaptation could compensate in part for the concomitant deficit in the ability of corticostriatal signals to activate spiny projection neurons and pause GPe activity. © 2019 International Parkinson and Movement Disorder Society.

Differences in Synaptic Dysfunction Between rTg4510 and APP/PS1 Mouse Models of Alzheimer's Disease

Genetically modified mice have provided insights into the progression and pathology of Alzheimer's disease (AD). Here, we have examined two mouse models of AD: the rTg4510 mouse, which overexpresses mutant human Tau gene, and the APP/PS1 mouse, which overexpresses mutant human genes for amyloid precursor protein and presenilin 1. Both models exhibit deficits in hippocampal function, but comparative analyses of these deficits are sparse. We used extracellular field potential recordings in hippocampal slices to study basal synaptic transmission (BST), paired-pulse facilitation (PPF), and long-term potentiation (LTP) at the Schaffer collateral-CA1 pyramidal cell synapses in both models. We found that 6-7, but not 2-3-month-old rTg4510 mice exhibited reduced pre-synaptic activation (fiber volley (FV) amplitude, ∼50%) and field excitatory post-synaptic potential (fEPSP) slope (∼40%) compared to wild-type controls. In contrast to previous reports, BST, when controlled for FV amplitude, was not altered in rTg4510. APP/PS1 mice (2-3 mo and 8-10 mo) had unchanged FV amplitude compared to wild-type controls, while fEPSP slope was reduced by ∼34% in older mice, indicating a deficit in BST. PPF was unchanged in 8-10-month-old APP/PS1 mice, but was reduced in 6-7-month-old rTg4510 mice. LTP was reduced only in older rTg4510 and APP/PS1 mice. Our data suggest that BST deficits appear earlier in APP/PS1 than in rTg4510, which exhibited no BST deficits at the ages tested. However, FV and synaptic plasticity deficits developed earlier in rTg4510. These findings highlight fundamental differences in the progression of synaptic pathology in two genetically distinct models of AD.

The pathophysiology of aortic cross-clamping

During open aortic surgery, interrupting the blood flow through the aorta by applying a cross-clamp is often a key step to allow for surgical repair. As a consequence, ischemia is induced in parts of the body distal to the clamp site. This significant alteration in the blood flow is almost always associated with hemodynamic changes. Upon release of the cross-clamp, the blood flow is restored, triggering an ischemia-reperfusion response, leading to many pathophysiological processes such as inflammation, humoral changes, and metabolite circulation that could lead to injury in many organ systems and may significantly influence the postoperative outcome. It is therefore important to understand these processes and how they can be treated in order to allow for safe surgical aortic repairs while ensuring the best possible outcomes.

The novel KMO inhibitor CHDI-340246 leads to a restoration of electrophysiological alterations in mouse models of Huntington's disease

Dysregulation of the kynurenine (Kyn) pathway has been associated with the progression of Huntington's disease (HD). In particular, elevated levels of the kynurenine metabolites 3-hydroxy kynurenine (3-OH-Kyn) and quinolinic acid (Quin), have been reported in the brains of HD patients as well as in rodent models of HD. The production of these metabolites is controlled by the activity of kynurenine mono-oxygenase (KMO), an enzyme which catalyzes the synthesis of 3-OH-Kyn from Kyn. In order to determine the role of KMO in the phenotype of mouse models of HD, we have developed a potent and selective KMO inhibitor termed CHDI-340246. We show that this compound, when administered orally to transgenic mouse models of HD, potently and dose-dependently modulates the Kyn pathway in peripheral tissues and in the central nervous system. The administration of CHDI-340246 leads to an inhibition of the formation of 3-OH-Kyn and Quin, and to an elevation of Kyn and Kynurenic acid (KynA) levels in brain tissues. We show that administration of CHDI-340246 or of Kyn and of KynA can restore several electrophysiological alterations in mouse models of HD, both acutely and after chronic administration. However, using a comprehensive panel of behavioral tests, we demonstrate that the chronic dosing of a selective KMO inhibitor does not significantly modify behavioral phenotypes or natural progression in mouse models of HD.

Chronic postsurgical pain: still a neglected topic?

Background

Surgical injury can frequently lead to chronic pain. Despite the obvious importance of this problem, the first publications on chronic pain after surgery as a general topic appeared only a decade ago. This study tests the hypothesis that chronic postsurgical pain was, and still is, represented insufficiently.

Methods

We analyzed the presentation of this topic in journal articles covered by PubMed and in surgical textbooks. The following signs of insufficient representation in journal articles were used: (1) the lack of journal editorials on chronic pain after surgery, (2) the lack of journal articles with titles clearly indicating that they are devoted to chronic postsurgical pain, and (3) the insufficient representation of chronic postsurgical pain in the top surgical journals.

Results

It was demonstrated that insufficient representation of this topic existed in 1981–2000, especially in surgical journals and textbooks. Interest in this topic began to increase, however, mostly regarding one specific surgery: herniorrhaphy. It is important that the change in the attitude toward chronic postsurgical pain spreads to other groups of surgeries.

Conclusion

Chronic postsurgical pain is still a neglected topic, except for pain after herniorrhaphy. The change in the attitude toward chronic postsurgical pain is the important first step in the approach to this problem.

Hypotension during gradual blood loss: waveform variables response and absence of tachycardia

BACKGROUND

Variation in arterial pressure and plethysmographic waveforms has been shown to be predictors of cardiac output response to fluid challenge. The objective of this study was to evaluate the ability of arterial and plethysmographic waveform variables to predict hypotension during blood loss.

METHODS

Patients undergoing autologous haemodilution were studied. After anaesthesia induction, blood was withdrawn in steps of 2% of estimated circulating blood volume (ECBV). Arterial and plethysmographic waveforms were recorded and analysed offline at each step of blood withdrawal.

RESULTS

Thirty-four (29%) out of 118 studied patients tolerated 20% ECBV withdrawal without hypotension. Patients who tolerated 20% ECBV withdrawal were younger than those who did not [mean (sd): 53.8 (11.1) vs 62.7 (10.7); P<0.0001]. Patients with hypertension developed hypotension earlier than healthier patients did. There were no differences at the baseline in arterial and plethysmographic waveform variables between those who did and those who did not tolerate 20% of ECBV withdrawal. All values of variables increased significantly from the baseline after the withdrawal of 4% of ECBV (P<0.005). There were no changes in heart rate (HR), 73 (12) at the baseline and 76 (13) after 20% of ECBV withdrawal (P=0.4).

CONCLUSIONS

Arterial and plethysmographic waveform variables were augmented with increasing blood loss in all patients. Older patients, patients who received anti-hypertensive drugs, or both developed hypotension earlier than others. Baseline values were weak predictors of hypotension during stepwise blood withdrawal. No clinically significant increase in HR was observed, regardless of tolerance of arterial pressure to blood withdrawal.

Chemical mediators of inflammation and resolution in post-operative abdominal aortic aneurysm patients

Temporal-metabolomic studies of local mediators during inflammation and its resolution uncovered novel pathways and mediators, e.g., lipoxins, resolvins, and protectins that stimulate key resolution responses. Since these studies were carried out with isolated human cells and in animal models, it is important to determine in humans whether temporal profiles between pro-inflammatory mediators and pro-resolving mediators are demonstrable in vivo. To this end, we examined patients undergoing abdominal aortic aneurysm (AAA) surgery. Profiles of mediators including eicosanoids were assessed in addition to pro-resolving mediators. The results demonstrate temporal relationships for local-acting peptides (e.g., VEGF, IL-10, TGF(β)) and lipid mediators (leukotrienes and resolvins). In addition, profiles obtained for AAA patients divided into two groups based on their temporal profile: one group consistent with a pro-inflammatory and another with a resolving profile. Together, these translational metabolomic profiles demonstrate for the first time the temporal relationships between local mediators in humans relevant in inflammation resolution.

Heterogeneous release probabilities and activity-dependent short-term synaptic depression

Synaptic transmission is a major mechanism by which neurons communicate with each other. Basic steps in neurotransmitter release are similar in all synapses. However, many properties of release vary between synapses and reflect specific structural and functional requirements, endowing synapses with specialized functions. Recently, Gelman et al.1 described properties of release and short-term depression at specialized nicotinic synapses in the brainstem of goldfish, Carassius auratus (Linnaeus). These axo-axonic synapses between the Mauthner cell collaterals and their targets, cranial relay neurons (CRNs), exhibit strong short-term depression, even at stimulation frequencies as low as 0.33 Hz. In short, amplitudes of post-synaptic responses, evoked by presynaptic trains of action potentials, were depressed with a time course approximated by a sum of two exponential functions. Initially, fast depression reduced the amplitude of EPSP(2) (response after the second stimulus), to less than 50% of EPSP(1) (response after the first stimulus). This was followed by a slow component of depression that produced an additional 10-30% amplitude reduction over a time-span of tens to hundreds of seconds. Interestingly, depressed EPSPs exhibited longer latencies than that of the "undepressed" EPSP1. Additionally, fast and slow calcium chelators (BAPTA and EGTA), injected pre-synaptically, were equally potent in reducing release. These data are consistent with a previously proposed general mechanism that assumes a change in release probability after the initial release. However, in an alternative interpretation the results could be coherently explained by postulating two releasable pools of vesicles, with high and low release probabilities, and a generally accepted depletion scheme. This latter interpretation will be discussed in this article.

Atypical properties of release and short-term depression at a specialized nicotinic synapse in the Mauthner cell network

Many synapses exhibit temporally complex forms of activity-dependent short-term synaptic plasticity. The diversity of these phenomena reflects the evolutionary specialization of synapses within networks. We examined the properties of transmission and plasticity, in vivo, at an identified, specialized axo-axonic nicotinic synapse between the goldfish Mauthner cell and one of its targets, the cranial relay neuron (CRN), using intracellular paired recordings and low frequency (0.33-2 Hz) train stimulations. Depression of successive excitatory postsynaptic potentials (EPSPs), which dominates short-term plasticity, had two components. A fast component reduced the amplitude of EPSP(2), to less than 50% of EPSP(1). A slow component produced an additional 10-30% of amplitude reduction and developed with a time constant of tens of seconds. The latencies of the later depressed responses were ∼0.1 ms longer than that of EPSP(1), suggesting a reduced release probability. The Ca(2+) chelators EGTA and BAPTA, injected presynaptically, reduced all EPSPs and slowed development of the second component of depression. Interestingly, spike broadening, produced by injecting K(+) channel blockers, reduced release, but accelerated the kinetics of the slow component. Finally, Ba(2+) in the external medium enhanced release, and reduced the first component and slowed the development of the second component of depression. Taken together, these last two results, which are in contrast to observations at other synapses, and the two-component depression suggest atypical release properties at the output synapses of the Mauthner cell, which triggers an escape behavior. We suggest that the second component of depression provides an additional safety factor to prevent repetitive firing of the CRN.

Lateral-line activity during undulatory body motions suggests a feedback link in closed-loop control of sea lamprey swimming

The lateral-line system is common to most aquatic organisms. It plays an important role in behaviours involving detection of other animals and obstacles. In gnathostome fishes, these behaviours appear to be dependent on an efferent inhibitory system that filters out stimuli caused by the animal’s own movement. Sea lampreys ( Petromyzon marinus L., 1758), the most basal extant vertebrate, possess a functional lateral-line system. Yet they completely lack the inhibitory efferent system. Thus, they may use the lateral line to sense their own swimming movements, helping to stabilize swimming. To test this hypothesis, we first investigated the kinematics of free-swimming lampreys. In an intact tethered preparation, we then generated undualatory body motions of comparable amplitude and frequency to swimming, while monitoring the evoked responses of the posterior lateral-line nerve. Last, we tested the effect of eliminating lateral-line inputs by cobalt treatment. In the tethered preparation, we recorded distinctive and consistent activity in the lateral-line nerve that was strongly dependent on characteristics of the motion. We found that distinct characteristics of the rhythmic movements are encoded in the temporal characteristics of the response. Swimming kinematics of cobalt-treated animals differed from controls, suggesting a complex, yet necessary role of the lateral-line system in closed-loop control of swimming.

Metamorphosis-related changes in the lateral line system of lampreys, Petromyzon marinus

Lamprey metamorphosis leads to considerable changes in morphology and behavior. We have recently reported that larval lampreys possess a functional lateral line system. Here we investigated metamorphic morphological changes in the lateral line system using light and electron microscopy. Functional modifications were studied by recording the trunk lateral line nerve activity of larvae and adults while stimulating neuromasts with approximately sinusoidal water motion. We found a general re-patterning of neuromasts on the head and trunk including an increase in numbers, redistribution within the pit lines, and shifts of the pit lines relative to external features. The trunk lateral line nerve response was qualitatively similar in adults and larvae. Both showed two neuronal populations responding to opposite directions of water flow. Magnitude of the response increased monotonically with stimulus amplitude. At low frequencies, the response lag relative to the stimulus maximum was approximately 220 degrees , and the gain depended approximately linearly on frequency, confirming that superficial neuromasts are velocity detectors. Changes in phase lag with increasing stimulus frequency were steeper in larvae, suggesting slower afferent conductance. The response gain with frequency was smaller for adults, suggesting a narrower frequency discrimination range and decreased sensitivity. These changes may be adaptations for the active lifestyle of adult lampreys.

Anesthetics impact the resolution of inflammation

BACKGROUND

Local and volatile anesthetics are widely used for surgery. It is not known whether anesthetics impinge on the orchestrated events in spontaneous resolution of acute inflammation. Here we investigated whether a commonly used local anesthetic (lidocaine) and a widely used inhaled anesthetic (isoflurane) impact the active process of resolution of inflammation.

METHODS AND FINDINGS

Using murine peritonitis induced by zymosan and a systems approach, we report that lidocaine delayed and blocked key events in resolution of inflammation. Lidocaine inhibited both PMN apoptosis and macrophage uptake of apoptotic PMN, events that contributed to impaired PMN removal from exudates and thereby delayed the onset of resolution of acute inflammation and return to homeostasis. Lidocaine did not alter the levels of specific lipid mediators, including pro-inflammatory leukotriene B(4), prostaglandin E(2) and anti-inflammatory lipoxin A(4), in the cell-free peritoneal lavages. Addition of a lipoxin A(4) stable analog, partially rescued lidocaine-delayed resolution of inflammation. To identify protein components underlying lidocaine's actions in resolution, systematic proteomics was carried out using nanospray-liquid chromatography-tandem mass spectrometry. Lidocaine selectively up-regulated pro-inflammatory proteins including S100A8/9 and CRAMP/LL-37, and down-regulated anti-inflammatory and some pro-resolution peptides and proteins including IL-4, IL-13, TGF-â and Galectin-1. In contrast, the volatile anesthetic isoflurane promoted resolution in this system, diminishing the amplitude of PMN infiltration and shortening the resolution interval (Ri) approximately 50%. In addition, isoflurane down-regulated a panel of pro-inflammatory chemokines and cytokines, as well as proteins known to be active in cell migration and chemotaxis (i.e., CRAMP and cofilin-1). The distinct impact of lidocaine and isoflurane on selective molecules may underlie their opposite actions in resolution of inflammation, namely lidocaine delayed the onset of resolution (T(max)), while isoflurane shortened resolution interval (Ri).

CONCLUSIONS

Taken together, both local and volatile anesthetics impact endogenous resolution program(s), altering specific resolution indices and selective cellular/molecular components in inflammation-resolution. Isoflurane enhances whereas lidocaine impairs timely resolution of acute inflammation.

Larval lampreys possess a functional lateral line system

Morphology of larval lampreys' neuromasts was found to be very similar to that of adults. Activity in the lateral line nerve, elicited by a vibrating ball, indicated a functional lateralis system. Analysis revealed at least two populations of afferents, responding to opposite directions of water flow, with adapting responses. The response magnitude increased monotonically with stimulus amplitude. Larval lampreys' neuromasts were less sensitive than those of teleosts. At low frequencies the response showed a phase lead of 200-220 degrees with respect to the maximum of the ball displacement and a gain that was approximately linearly proportional to frequency.

A demographic, service, and financial survey of anesthesia training programs in the United States

In February 2000, a demographic, service, and finance survey was sent to the directors of anesthesiology training programs in the United States under the auspices of the Society of Academic Anesthesia Chairs/Association of Academic Program Directors. In August of 2000, 2001, and 2002, shorter follow-up surveys were sent to the same program directors requesting the numbers of vacancies in faculty positions and certified registered nurse anesthetists (CRNA) positions. The August 2001 survey also inquired if departments had positive or negative financial margins for the fiscal year ending June 2001. The August 2002 survey included the questions of the 2001 survey and additionally asked if the departments had had an increase or decrease in institutional support and the amount of that current support. The survey results revealed that the average program had 36 anesthetizing locations and 36 faculty. Those faculty spent 69% of their time providing clinical service. Approximately one-half of the departments paid for some of their residents, whereas the other 50% paid for none. Eighty-five percent of the departments employed CRNAs who were funded by the hospital in one third of the departments. In 2000, departments received $34,319/yr in support per faculty full-time equivalent (FTE) from their institutions and had a mean revenue of $407,000/yr/faculty FTE. In 2002, the department's institutional support per FTE increased to $59,680 (a 74% increase since 2000). The departments in academic medical centers paid 20% in overhead expenses, whereas departments in nonacademic medical centers paid 10%. In 2000, 2001, and 2002, the percentage of departments with positive margins was 53%, 53%, and 65%, respectively, whereas the departments with a negative margin decreased from 44% in the year 2000 to 38% in 2001 and 33% in 2002. For the departments with a positive margin, the amount of margin per FTE over this 3-yr period was approximately $50,000, $15,000, and $30,000, respectively. Although the percentage of departments with a negative margin has been decreasing, the negative margin per FTE seems to be increasing from approximately $24,000 to $43,000. The number of departments with open faculty positions has decreased from 91.5% in the year 2000 to 83.5% in 2001 and 78.4% in 2002; in these departments, the number of open faculty positions has also decreased from 3.8 in 2000 to 3.9 in 2001 to 3.4 in 2002. The number of open CRNA positions seems to have been relatively constant with approximately two thirds of the departments requiring an average of approximately four CRNAs each. Overall, academic anesthesiology departments fiscal security seems to have eroded with an increased dependence on institutional support. Departments pay larger overhead rates relative to private practice, and there seems to be a continued, but possibly decreasing, shortage of faculty.

IMPLICATIONS

A survey was conducted of anesthesia training program directors that demonstrated that their departments' financial conditions have been eroding over the years 2000 to 2002. During this same period of time, departments were receiving an increase in institutional support from $34,319/full-time equivalent (FTE) faculty in the year 2000 to $59,680/FTE in the year 2002. Although there seems to be an approximate 10% shortage in academic faculty, the number of departments with open positions has progressively decreased from 91% to 73% over the past 3 yr. On average, the financial condition of the training departments has deteriorated over the past 3 yr despite a significant increase in institutional support to enable departments to recruit and retain faculty in an era of an apparent national shortage of anesthesiologists.

Transient paraplegia after stent grafting of a descending thoracic aortic aneurysm treated with cerebrospinal fluid drainage

We present a case of descending thoracic aortic aneurysm repair using an endovascular stent graft, complicated by postoperative paraplegia, which was successfully treated by placing a spinal drain. The case highlights the importance of the concept of collateral flow to the spinal cord and of choosing an anesthetic technique that allows immediate postoperative evaluation of lower extremity neurologic function.

Prospective double-blind study of effect of ketorolac administration after laparoscopic urologic surgery

BACKGROUND AND PURPOSE

To decrease postoperative dependence on narcotics for analgesia, we have evaluated ketorolac as an adjunct to perioperative pain control in patients undergoing laparoscopic urologic surgery.

PATIENTS AND METHODS

Sixty-five patients (34 male, 31 female) were randomized to receive either ketorolac tromethamine (15-30 mg IV q 6 h) or placebo prior to laparoscopic surgery. Patient-controlled analgesia in the form of morphine sulfate was provided. Operative factors such as the type of surgery, operative time, and estimated blood loss were recorded. Postoperative factors such as analog pain score (range 0-10), narcotic usage, and length of stay were evaluated.

RESULTS

Fifty-five patients completed the study. The average pain score was 2.2 and 4.5 for the ketorolac and placebo groups, respectively (P < 0.005). The mean amounts of total morphine used were 39.2 mg (ketorolac) and 62.5 mg (placebo) (P = 0.077). The length of stay was not significantly different in the ketorolac (2.5 days) and placebo (2.6 days) groups (P = 0.74). Operative times (P = 0.21) and estimated blood loss (P = 0.60) were not significantly different in the two groups. Ketorolac did not adversely affect renal function; serum creatinine changes were not significantly different from those in the patients receiving placebo (P = 0.50). Laparoscopic pyeloplasty necessitated more narcotic analgesia than did other laparoscopic procedures (P = 0.05).

CONCLUSION

Ketorolac decreases the subjective perception of pain after laparoscopic urologic surgery. It is suggested that ketorolac administration decreases the amount of narcotic usage as well. Time to resumption of oral intake and length of hospital stay were not influenced by use of ketorolac.

Raised interleukin-6 levels in obese patients

OBJECTIVE

Obese patients demonstrate a variety of biochemical, metabolic, and pulmonary abnormalities. Inflammatory mediators such as tumor necrosis factor-alpha and interleukin-6 (IL-6) may have a direct effect on glucose and lipid metabolism. Hypoxemia in itself induces release of IL-6. The aim of this study was to examine the relationship between IL-6 levels in healthy volunteers (control group) and three different groups of obese patients: patients without obstructive sleep apnea syndrome (OSAS), patients with OSAS, and patients with obesity hypoventilation syndrome (OHS) (daytime baseline oxygen saturation of <93%).

RESEARCH METHODS AND PROCEDURES

We measured serum IL-6 levels in 25 obese patients (body mass index of >35 kg/m2) and 12 healthy women.

RESULTS

The results demonstrate statistically significant differences in serum IL-6 levels between the control group (1.28 +/- 0.85 pg/mL) and obese patients without OSAS (7.69 +/- 5.06 pg/mL, p < 0.05) and with OSAS (5.58 +/- 0.37 pg/mL, p < 0.0005). In the patients with OHS, IL-6 concentrations were highest (43.13 +/- 24.27 pg/mL).

DISCUSSION

We conclude that serum IL-6 is increased in obese patients. The highest IL-6 levels were found in the patients with OHS.

Perioperative renal protection

Acute renal failure continues to complicate the postoperative courses of our vascular and cardiac surgical patients, dramatically increasing mortality and decreasing quality of life when it occcurs. In spite of better understanding of the disease, few gains have been made in its prevention. We review its pathophysiology and discuss the most recent developments that may eventually lead to perioperative renal protection.