Superficial versus deep parasternal intercostal plane blocks: cadaveric evaluation of injectate spread.

BACKGROUND: Deep and superficial parasternal intercostal plane blocks provide anterior chest wall analgesia for both breast and cardiac surgery. Our primary objective of this cadaveric study was to describe the parasternal spread of deep and superficial parasternal intercostal plane blocks. Our secondary objectives were to describe needle proximity to the internal mammary artery when performing deep parasternal intercostal plane blocks, and compare lateral injectate spread and extension into the rectus sheath. METHODS: We performed ultrasound-guided deep and superficial parasternal intercostal plane blocks 2 cm from the sternum at the T3-4 interspace in four fresh frozen cadavers as described in clinical studies. RESULTS: Parasternal spread of injectate was greater with the deep parasternal intercostal plane injection than with the superficial parasternal intercostal plane injection. The internal mammary artery was ∼3 mm away from the needle trajectory in cadaver #1 and ∼5 mm from the internal mammary artery in cadaver #2. Lateral spread extended to the midclavicular line for all deep parasternal intercostal plane blocks and beyond the midclavicular line for all superficial parasternal intercostal plane blocks. Neither block extended to the rectus sheath. CONCLUSIONS: A greater number of parasternal interspaces were covered with the deep parasternal intercostal plane block than with the superficial parasternal intercostal plane block when one injection was performed at the T3-4 interspace. However, considering proximity to the internal mammary artery, and potential devastating consequences of an arterial injury, we propose that the deep parasternal intercostal plane block be classified as an advanced block and that future studies focus on optimising superficial parasternal intercostal plane parasternal spread.

Deep Parasternal Intercostal Plane Block for Postoperative Analgesia After Sternotomy for Cardiac Surgery-A Retrospective Cohort Study.

OBJECTIVE: To examine the analgesic efficacy of postoperative deep parasternal intercostal plane (DPIP) blocks for patients having cardiac surgery via median sternotomy. DESIGN: This single-center retrospective study compared patients receiving bilateral DPIP blocks with a matched cohort of patients not receiving DPIP blocks. SETTING: Large quaternary referral center. PARTICIPANTS: Adult patients admitted to the authors' institution from January 1, 2016, to August 14, 2020, for elective cardiac surgery via median sternotomy. INTERVENTIONS: Patients received ultrasound-guided bilateral DPIP blocks. MEASUREMENTS AND MAIN RESULTS: A total of 113 patients received a DPIP block; 3,461 patients did not. The estimated multiplicative change in cumulative opioid consumption through 24 hours was 0.42 (95% CI 0.32-0.56; p < 0.001), indicating that patients receiving DPIP blocks required 60% fewer opioids than patients who did not. Proportional odds ratios for the average pain score on postoperative day (POD) 0 was 0.46 (95% CI 0.32-0.65; p < 0.001), and POD 1 was 0.67 (95% CI 0.47-0.94; p = 0.021), indicating lower pain scores for patients receiving blocks. The exploratory analysis identified an inverse correlation between DPIP blocks and atrial fibrillation incidence (2% v 15%; inverse probability of treatment weighting odds ratio 0.088, 95% CI 0.02-0.41; p = 0.002). CONCLUSIONS: The use of DPIP blocks in patients undergoing cardiac surgery via median sternotomy was associated with less opioid use and improved pain scores in the early postoperative period compared with patients not receiving blocks. Prospective randomized controlled studies should further elucidate the efficacy and risks of DPIP blocks in cardiac surgery.

Pectoral Fascial Plane Versus Paravertebral Blocks for Minimally Invasive Mitral Valve Surgery Analgesia.

OBJECTIVES: This study examined the postoperative analgesic efficacy of single-injection pectoral fascial plane (PECS) II blocks compared to paravertebral blocks for elective robotic mitral valve surgery. DESIGN: A single-center retrospective study that reported patient and procedural characteristics, postoperative pain scores, and postoperative opioid use for patients undergoing robotic mitral valve surgery. SETTING: This investigation was performed at a large quaternary referral center. PARTICIPANTS: Adult patients (age ≥18) admitted to the authors' hospital from January 1, 2016, to August 14, 2020, for elective robotic mitral valve repair who received either a paravertebral or PECS II block for postoperative analgesia. INTERVENTIONS: Patients received an ultrasound-guided, unilateral paravertebral or PECS II nerve block. MEASUREMENTS AND MAIN RESULTS: One hundred twenty-three patients received a PECS II block, and 190 patients received a paravertebral block during the study period. The primary outcome measures were average postoperative pain scores and cumulative opioid use. Secondary outcomes included hospital and intensive care unit lengths of stay, need for reoperation, need for antiemetics, surgical wound infection, and atrial fibrillation incidence. Patients receiving the PECS II block required significantly fewer opioids in the immediate postoperative period than the paravertebral block group, and had comparable postoperative pain scores. No increase in adverse outcomes was noted for either group. CONCLUSIONS: The PECS II block is a safe and highly effective option for regional analgesia for robotic mitral valve surgery, with demonstrated efficacy comparable to the paravertebral block.

Media Multitasking in Medical Students: A Theory-Based Approach to Understanding this Behavior.

PHENOMENON: While technology is useful and encouraged in medical school, the effect of media multitasking on academic performance remains concerning. Past research has investigated performance and cognitions associated with college students' in-class media multitasking behavior, but the extent and correlates among medical students is relatively unknown. APPROACH: We surveyed medical students at our institution to quantify media multitasking behaviors and related beliefs, and we collected corresponding course grades. Our research applies the Integrative Model of Behavioral Prediction theory to analyze course and cognitive factors influencing media multitasking behavior in medical students. Correlation of media multitasking behavior with average and block grades assessed potential academic impact of the behavior. FINDINGS: Media multitasking was common among medical students. Reported extent of media multitasking among medical students (N = 119) was not related to course grades but was driven by an interplay of beliefs about the behavior and specific course factors. Based on our hierarchical regression model, concerns about boredom appear to be the major cognitive belief underlying behavior. INSIGHTS: Our findings, in the context of the Integrative Model of Behavioral Prediction theory, show influential factors that impact medical students' behavior regarding media multitasking. A campaign targeting these factors influencing behavior may be the most effective approach to limit students' media multitasking and its potential impact on performance. Though our research did not find an association between the extent of media multitasking and course grades, our study was limited by self-report of media multitasking and relatively crude measures of academic performance. Further research is required to measure these behaviors and potential outcomes.Supplemental data for this article is available online at.

Copper primes adaptation of uropathogenic Escherichia coli to superoxide stress by activating superoxide dismutases.

Copper and superoxide are used by the phagocytes to kill bacteria. Copper is a host effector encountered by uropathogenic Escherichia coli (UPEC) during urinary tract infection in a non-human primate model, and in humans. UPEC is exposed to higher levels of copper in the gut prior to entering the urinary tract. Effects of pre-exposure to copper on bacterial killing by superoxide has not been reported. We hypothesized that copper-replete E. coli is more sensitive to killing by superoxide in vitro, and in activated macrophages. We utilized wild-type UPEC strain CFT073, and its isogenic mutants lacking copper efflux systems, superoxide dismutases (SODs), regulators of a superoxide dismutase, and complemented mutants to address this question. Surprisingly, our results reveal that copper protects UPEC against killing by superoxide in vitro. This copper-dependent protection was amplified in the mutants lacking copper efflux systems. Increased levels of copper and manganese were detected in UPEC exposed to sublethal concentration of copper. Copper activated the transcription of sodA in a SoxR- and SoxS-dependent manner resulting in enhanced levels of SodA activity. Importantly, pre-exposure to copper increased the survival of UPEC within RAW264.7 and bone marrow-derived murine macrophages. Loss of SodA, but not SodB or SodC, in UPEC obliterated copper-dependent protection from superoxide in vitro, and from killing within macrophages. Collectively, our results suggest a model in which sublethal levels of copper trigger the activation of SodA and SodC through independent mechanisms that converge to promote the survival of UPEC from killing by superoxide. A major implication of our findings is that bacteria colonizing copper-rich milieus are primed for efficient detoxification of superoxide.

Experimental Effects of Tweets Encouraging Social Distancing: Effects of Source, Emotional Appeal, and Political Ideology on Emotion, Threat, and Efficacy.

CONTEXT: Public health officials and celebrities use social media to provide guidance to reduce the spread of COVID-19. Messages apply different promotional strategies to motivate behavior change, likely yielding divergent reactions from partisan audiences. The Extended Parallel Process Model (EPPM) suggests that perceived threat for a negative outcome should impact perceived need for the advocated health behavior, which should be more appealing to an audience if perceived it to be efficacious and feasible. OBJECTIVE: This study examines the interactive effects of Tweet source, message emotional appeal, and audience political affiliation on US adults' perceptions of COVID-19 threat and social distancing efficacy during early months of the pandemic. DESIGN AND SETTING: This online survey experiment applies the EPPM to assess US adults' reactions to tweets encouraging social distancing. The experiment tests 3 emotional appeals (fear, humor, and neutral) and 2 sources (Centers for Disease Control and Prevention [CDC] and celebrity) on adults' emotional reactions and perceptions of COVID-19 threat and social distancing efficacy. PARTICIPANTS: The final sample included 415 US adults (242 Democrat and 173 Republican) recruited through Amazon's Mechanical Turk. MAIN OUTCOME MEASURES: Outcome measures were adapted from the EPPM and include perceived susceptibility to and severity of COVID-19, and response efficacy and self-efficacy regarding social distancing. Each was measured through the survey on a 7-point response scale. RESULTS: Humor and fear appeal messages evoked less fear and guilt responses than a neutral tweet from the CDC. Fear and guilt emotions predicted greater perceived threat, while hope and pride predicted efficacy constructs in relationships moderated by political ideology. CONCLUSIONS: Public health messages targeting a bipartisan audience through social media may increase perceived threat by inducing fear of COVID-19 infection. EPPM theory suggests boosting efficacy is also critical to message acceptance and behavior change; thus, inducing feelings of hope and pride in addition to fear may be particularly effective.

Stellate Ganglion Blockade for Refractory Ventricular Arrhythmias: Implications of Ultrasound-Guided Technique and Review of the Evidence.

Refractory ventricular arrhythmias (VAs) carry high mortality rates despite electrical and pharmacologic therapy utilization. These patients often require aggressive hemodynamic support, including mechanical circulatory devices such as extracorporeal membrane oxygenation because of progressive hemodynamic and metabolic deterioration. Sympathetic nervous system stimulation and neuronal remodeling after myocardial insults have been implicated as drivers of refractory VAs. This understanding has led to interest in and a growing body of experience with percutaneous blockade of the stellate ganglion as a means of interrupting the vicious cycle of refractory VAs. A number of techniques have been described for stellate ganglion blockade, including landmark-driven approaches, fluoroscopy-assisted blockade, and ultrasound guidance. Herein, the literature is evaluated and the authors' experience with stellate ganglion blockade using ultrasound guidance for refractory VAs is described.

Asymmetrical selection maintains heritable phenotypic variation between two subspecies of Monardella villosa.

PREMISE: Monardella villosa is an evolutionarily young species complex distributed across a large geographic range. Our goal was to determine whether the phenotypic difference between two subspecies of M. villosa was heritable and whether the alternative phenotypes were adaptive to their respective local habitats. METHODS: We collected seeds from 25 populations of M. villosa, 14 from subspecies franciscana, which grows closer to the coast, and 11 from subspecies villosa, which has a larger and more inland geographic distribution. We reciprocally transplanted the two subspecies into their respective habitats and compared plant germination, post-emergence survival, and growth. We used linear mixed models to quantify the effects of genotype and environment to determine whether subspecies were locally adapted and whether leaf traits that distinguish these subspecies were genetically based. RESULTS: Plants of both subspecies grown at the coastal site had significantly lower survival and biomass than the inland site. The subspecies were not locally adapted; however, the coastal subspecies franciscana did have a home site advantage. We also found that distinctive leaf morphological traits were genetically based, with high broad-sense heritability of traits. CONCLUSIONS: The two subspecies of Monardella villosa were not locally adapted to their respective habitat, but rather we found that selection for local genotypes may be stronger at the coastal site. Despite the lack of evidence for local adaptation in the strict sense, the subspecies had heritable variation in several leaf phenotypes, indicating that heterogeneous selection imposes an adaptive trade-off for leaf trichome production within this species.

Standardized practice design with electronic support mechanisms for surgical process improvement: reducing mechanical ventilation time.

BACKGROUND: Hospital surgical care is complex and subject to unwarranted variation. OBJECTIVE: As part of a multiyear effort, we sought to reduce variability in intraoperative care and management of mechanical ventilation in cardiac surgery. We identified a patient population whose care could be standardized and implemented a protocol-based practice model reinforced by electronic mechanisms. METHODS: In a large cardiac surgery practice, we built a standardized practice model between 2009 and 2011. We compared mechanical ventilation time before (2008) and after (2012) implementation. To ensure groups were comparable, propensity analysis matched patients from the 2 operative years. RESULTS: In 2012, more than 50% of all cardiac surgical patients were managed with our standardized care model; of those, 769 were one-to-one matched with patients undergoing surgery in 2008. Patients had a mix of coronary artery bypass grafting, valve surgery, and combined procedures. Our practice model reduced median mechanical ventilation duration from 9.3 to 6.3 hours (2008 and 2012) (P < 0.001) and intensive care unit length of stay from 26.3 to 22.5 hours (P < 0.001). Reintubation and intensive care unit readmission were unchanged. Variability in ventilation time was also reduced. CONCLUSIONS: We demonstrate that in more than 50% of all cardiac surgical patients, a standardized practice model can be used to achieve better results. Clinical outcomes are improved and unwarranted variability is reduced. Success is driven by clear patient identification and well-defined protocols that are clearly communicated both by electronic tools and by empowerment of bedside providers to advance care when clinical criteria are met.

Some considerations of the tolerability of ketamine for ECT anesthesia: a case series and review of the literature.

Most anesthetic agents used for electroconvulsive therapy (ECT) have few intrinsic adverse effects. Ketamine, however, is well known to be associated with a variety of adverse effects including nausea, dizziness, and psychotomimetic phenomena. Over the past several decades, there have been numerous reports on the use of ketamine for ECT anesthesia, with varied assessments on how prominent these adverse effects are in the ECT situation. Ketamine has received a resurgence of interest as an ECT anesthetic of late owing to its established independent antidepressant effects and to theoretical reasons why it might lessen the cognitive adverse effects of ECT. In this case series, the author reviews the experience with 14 patients who had undergone ECT who were switched to ketamine as anesthetic from methohexital at the preference of the treating anesthesiologist. All 14 patients spontaneously reported a strong preference not to be given ketamine again due to bothersome adverse effects. The latter consisted of either vestibular-type symptoms (nausea/vomiting, dizziness, and vertigo) or psychotomimetic effects (dissociative phenomena). It is concluded that ketamine is not free of adverse effects when used as an ECT anesthetic. Electroconvulsive therapy clinicians should be vigilant about assessing for these effects when ketamine is used, and consideration should be given to using a benzodiazepine such as diazepam or midazolam at seizure termination when ketamine anesthesia is used to prevent bothersome adverse effects seen upon awakening.

Anesthetic-induced pain on injection in electroconvulsive therapy: review of the literature and suggestions for prevention.

Pain on injection (angialgia) is a common adverse effect of anesthetic medications, especially propofol and methohexital, which are both used for electroconvulsive therapy (ECT). In this review, the authors survey some general literature on angialgia incidence, mechanisms, and prevention efforts in non-ECT settings and follow this with a review of similar topics relevant to ECT. They review practical methods of angialgia prevention for ECT patients. The methods with the best research basis include the use of an antecubital vein for intravenous access as well as the local anesthetic lidocaine. Regarding the latter, concerns regarding shortening of seizure duration during ECT have been raised. If lidocaine is used for angialgia in ECT, low doses should be administered to avoid possible interference with ictal electroencephalogram expression. Other methods worth studying further for angialgia during ECT include use of the antiemetic agent metoclopramide and high-potency opiates.

The inner membrane protein YhiM links copper and CpxAR envelope stress responses in uropathogenic E. coli.

Urinary tract infection (UTI) is a ubiquitous infectious condition, and uropathogenic Escherichia coli (UPEC) is the predominant causative agent of UTI. Copper (Cu) is implicated in innate immunity, including against UPEC. Cu is a trace element utilized as a co-factor, but excess Cu is toxic due to mismetalation of non-cognate proteins. E. coli precisely regulates Cu homeostasis via efflux systems. However, Cu import mechanisms into the bacterial cell are not clear. We hypothesized that Cu import defective mutants would exhibit increased resistance to Cu. This hypothesis was tested in a forward genetic screen with transposon (Tn5) insertion mutants in UPEC strain CFT073, and we identified 32 unique Cu-resistant mutants. Transposon and defined mutants lacking yhiM, which encodes a hypothetical inner membrane protein, were more resistant to Cu than parental strain. Loss of YhiM led to decreased cellular Cu content and increased expression of copA, encoding a Cu efflux pump. The CpxAR envelope stress response system was activated in the ΔyhiM mutant as indicated by increased expression of cpxP. Transcription of yhiM was regulated by CueR and CpxR, and the CpxAR system was essential for increased Cu resistance in the ΔyhiM mutant. Importantly, activation of CpxAR system in the ΔyhiM mutant was independent of NlpE, a known activator of this system. YhiM was required for optimal fitness of UPEC in a mouse model of UTI. Our findings demonstrate that YhiM is a critical mediator of Cu homeostasis and links bacterial adaptation to Cu stress with the CpxAR-dependent envelope stress response in UPEC.IMPORTANCEUPEC is a common bacterial infection. Bacterial pathogens are exposed to host-derived Cu during infection, including UTI. Here, we describe detection of genes involved in Cu homeostasis in UPEC. A UPEC mutant lacking YhiM, a membrane protein, exhibited dramatic increase in resistance to Cu. Our study demonstrates YhiM as a nexus between Cu stress and the CpxAR-dependent envelope stress response system. Importantly, our findings establish NlpE-independent activation of CpxAR system during Cu stress in UPEC. Collectively, YhiM emerges as a critical mediator of Cu homeostasis in UPEC and highlights the interlinked nature of bacterial adaptation to survival during Cu and envelope stress.

Effect of drinker type on water disappearance of nursery pigs.

This study was conducted to evaluate the water disappearance of nursery pigs (from weaning to 6 wk post-weaning; 6.4 ±â€…1.07 to 22.0 ±â€…3.39 kg live body weight) using a randomized complete block design to compare two Drinker Type treatments: Nipple vs. Cup. A total of 336 pigs housed in 16 pens with 21 pigs per pen in 2 rooms (8 pens per room) were used. Pens had fully-slatted concrete floors; floor space was 0.32 m2/pig and there was one feeder and one drinker per pen. Pigs were fed corn-soybean-based diets formulated to meet or exceed nutrient requirements. Pigs and feeders were weighed at the start and end of the study. Water disappearance was measured using a water-flow meter fitted to the water pipeline supplying the drinker in each pen. For the overall study period, Drinker Type did not affect (P > 0.05) growth performance; however, average daily water disappearance was greater (P < 0.05) for Nipple than Cup drinkers (2.74 and 2.25 liters/d, respectively; SEM = 0.139). Water to feed disappearance ratio was greater (P < 0.05) for the Nipple than the Cup treatment (5.23 vs. 4.22 liters:kg, respectively; SEM = 0.263). These results suggest that water disappearance from nipple drinkers was greater than for cup drinkers. The lack of an effect of Drinker Type treatment on pig growth performance suggests that the treatment difference for water disappearance was most likely due to greater water wastage for the nipple drinkers rather than any effect on water intake per se.

Cardiac tamponade in a patient supported by veno-arterial extracorporeal membrane oxygenation.

Cardiac tamponade occurring in a patient supported on central veno-arterial extracorporeal membrane oxygenation is depicted in a transesophageal echocardiography image and associated rendering. Prompt recognition of tamponade, which can be assisted with echocardiography, and emergent evacuation is critical to restoring cardiovascular stability.

Influence of high cyclic ambient temperature and water drinker design on growth performance and water disappearance of growing-finishing pigs.

The objective of this study was to determine effects of room temperature and drinker design on growth and water disappearance of growing-finishing pigs (26.9 ±â€…3.67 to 130.9 ±â€…5.10 kg live body weight). A split-plot design was used with a 2 × 2 factorial arrangement of treatments: Room Temperature (RT) [Thermoneutral (TN) vs. High (HI); main plot], Drinker Design (DD; Nipple vs. Cup; sub-plot). A total of 316 pigs were used, housed in 32 pens in 4 rooms (8 pens/room; 7 pens of 10 pigs and 1 pen of 9 pigs). Two rooms were on each RT treatment. Room temperature for the TN treatment was constant throughout each day but decreased from 24°C at the start to 20°C and 18°C on d 14 and 45 of the study period, respectively. For the HI treatment, a single, cyclic RT protocol was used throughout the study (30°C from 08:00 to 19:00 h and 20°C from 20:00 to 07:00 h, with 1-h transition periods). Pens had fully-slatted concrete floors and 1 feeder and drinker (either nipple or cup); floor space was 0.67 m2/pig. Pigs had ad libitum access to standard corn-soybean diets, formulated to meet or exceed NRC (2012) nutrient requirements. Water disappearance was measured using a meter fitted to the water line supplying each drinker. There were no interactions (P > 0.05) between RT and DD treatments. Drinker Design did not affect (P > 0.05) growth performance; water disappearance was 7.3% greater (P ≤ 0.05) for Nipple than Cup drinkers. Compared to the TN treatment, the HI treatment had no effect (P > 0.05) on gain:feed ratio, but resulted in lower (P ≤ 0.05) average daily gain (6.5%) and average daily feed intake (5.5%) and greater (P ≤ 0.05) average daily water disappearance (16.8%). These results suggest that both drinker design and RT can affect water disappearance, and that the high, cyclic RT regime used reduced growth performance of growing-finishing pigs. Further research is needed to determine the contribution of water intake and wastage to treatment differences in water disappearance.

Paradoxical embolus caught in transit through a patent foramen ovale.

Diagnosing a paradoxical embolism is challenging, and it can be proven only if the thrombus is identified across the intracardiac defect. Very few cases have been diagnosed as an impending paradoxical embolism. Recently, the diagnosis and management of these entities have greatly improved with the advent of transesophageal echocardiography (compared with transthoracic echocardiography). Pulmonary hypertension may cause right-to-left shunting across a patent foramen ovale and predispose development of a paradoxical embolism. We report a patient with an impending paradoxical embolism that was caught in transit across the patent foramen ovale. The patient was treated successfully with emergent surgery.

Urban forest biodiversity and cardiovascular disease: Potential health benefits from California's street trees.

Enhanced immune functioning in response to biodiversity may explain potential health benefits from exposure to green space. Using unique data on urban forest biodiversity at the zip code level for California measured from 2014 to 2019 we test whether greater diversity of street trees is associated with reduced death from cardiovascular disease. We find that urban forests with greater biodiversity measured via the Shannon Index at the genus level are associated with a lower mortality rate for heart disease and stroke. Our estimates imply that increasing the Shannon Index by one standard deviation (0.64) is associated with a decrease in the mortality rate of 21.4 per 100,000 individuals for heart disease or 13% and 7.7 per 100,000 individuals for stroke or 16%. Our estimates remain robust across several sensitivity checks. A policy simulation for tree planting in Los Angeles based on our estimates suggests that if these relationships were causal, investment in planting for a more biodiverse set of street trees would be a cost-effective way to reduce mortality related to cardiovascular disease in urban areas.