Propofol Sedation in Pediatric Upper Endoscopy: A Study of Pharmacodynamics and the Effects of Gastroenterologists, Anesthesiologists, and Supervised Participants on the Procedure Time and Sedation Time.

Background and aims Propofol combined with fentanyl is a commonly used sedative for pediatric upper endoscopies (UEs). The primary aim was to study the association between propofol dose and procedure and sedation time. The secondary aims were to assess the pharmacodynamics of propofol use with fentanyl and evaluate if gastroenterologists' and anesthesiologists' years of experience or the presence of supervised participants (such as students, residents, and fellows) have any influence on the procedure and sedation time. Methods A retrospective study was performed at the Children's Hospital of Michigan on patients under 18 years who underwent UEs with propofol sedation with fentanyl over a two-year period. Results A correlation was found between the propofol amount used expressed per body mass index (BMI)/body surface area (BSA), procedure time, and sedation time (p < 0.0001). Throat pain was the most common post-procedural adverse event (4.48%). The impact of psychoactive drugs on these events was not statistically significant, but attention-deficit/hyperactivity disorder (ADHD) medication use was related to increased post-procedural pain complaints. The use of prescribed psychoactive medications was associated with larger propofol dose usage (p = 0.007) without a significant increase in sedation time. Individual gastroenterologists, their years of experience, and the presence of supervised participants were associated with different procedure times (p <0.0001, <0.0001, 0.01). Fellow participation was associated with a 1.11-minute procedure time increase (p = 0.04). Individual anesthesiologists, their years of experience, and the presence of supervised participants were associated with different sedation times (p <0.0001, <0.0001, 0.01). Conclusion We found a novel correlation between propofol dosing expressed by the BMI/BSA and sedation time. The UE procedure time and sedation time are associated with individual gastroenterologists and anesthesiologists, their years of experience, and the presence of supervised participants.

Preoperative ultrasound assessment of gastric content in patients with diabetes: A meta-analysis based on a systematic review of the current literature.

STUDY OBJECTIVE: To conduct a systematic literature review of the current evidence on the effect of diabetes mellitus on gastric volume observed during a preoperative ultrasound examination. Using the results of this systematic literature review, a meta-analysis was performed to investigate whether there was an association between diabetes mellitus and an increased risk of presenting with a high-risk stomach (gastric volume associated with an increased risk of pulmonary aspiration). DESIGN: Review article and meta-analysis. SETTING: Review of published literature. PATIENTS: A total of 3366 patients underwent surgery. INTERVENTION: Gastric ultrasound examination. MEASUREMENTS: Data for the meta-analysis and literature review were collected from the PubMed/Medline, Embase, Web of Science, and Google Scholar databases of the National Library of Medicine from the date of inception to January 2023. All included studies measured the gastric antral cross-sectional area and/or gastric residual volume in patients with diabetes and those without diabetes. The data utilized in the meta-analysis included all studies that evaluated the incidence of high-risk stomachs based on ultrasonographic measurements of the gastric antral cross-sectional area or gastric residual volume. MAIN RESULTS: Most collated studies revealed that diabetes mellitus was associated with increased antral cross-sectional area and gastric residual volume. A meta-analysis of published reports indicated that patients with diabetes have an increased rate of high-risk stomachs. CONCLUSIONS: Diabetes mellitus is associated with an increased rate of high-risk stomachs. The authors recommend large prospective trials to ascertain the safety of the current fasting guidelines for patients with diabetes undergoing surgery.

Neuraxial Anesthesia Significantly Reduces 30-Day Venous Thromboembolism Rate and Length of Hospital Stay in Primary Total Hip Arthroplasty: A Stratified Propensity Score-Matched Cohort Analysis.

BACKGROUND: General anesthesia (GA) has been the commonly used protocol for total hip arthroplasty (THA); however, neuraxial anesthesia (NA) has been increasingly performed. Our purpose was to compare NA and GA for 30-day postoperative outcomes in United States veterans undergoing primary THA. METHODS: A large veteran's database was utilized to identify patients undergoing primary THA between 1999 and 2019. A total of 6,244 patients had undergone THA and were included in our study. Of these, 44,780 (79.6%) had received GA, and 10,788 (19.2%) had received NA. Patients receiving NA or GA were compared for 30-day mortalities, cardiovascular, respiratory, and renal complications, and wound infections and hospital lengths of stay (LOS). Propensity score matching, multivariate regression analyses, and subgroup analyses by American Society of Anesthesiology classification were performed to control for selection bias and patient baseline characteristics. RESULTS: Upon propensity-adjusted multivariate analyses, NA was associated with decreased risks for deep venous thrombosis (odds ratio [OR] = 0.63; 95% CI = 0.4-0.9; P = .02), any respiratory complication (OR = 0.63; 95% CI = 0.5-0.9; P = .003), unplanned reintubation (OR = 0.51; 95% CI = 0.3-0.9; P = .009), and prolonged LOS (OR = 0.78; 95% CI = 0.72-0.84; P < .001). Subgroup analyses by American Society of Anesthesiology classes showed NA decreased 30-day venous thromboembolism rate in low-risk (class I/II) patients and decreased respiratory complications in high-risk (class III/IV) patients. CONCLUSION: Using a patient cohort obtained from a large national database, NA was associated with reduced risk of 30-day adverse events compared to GA in patients undergoing THA. Postoperative adverse events were decreased with NA administration with similar decreases observed across all patient preoperative risk levels. NA was also associated with a significant decrease in hospital LOS.

Interventions to prevent hypothermia in extremely preterm low-weight infants undergoing cardiac catheterisation.

BACKGROUND: In January 2019, a new device called the Amplatzer Piccolo Occluder was approved by the US Food and Drug Administration for percutaneous closure of patent ductus arteriosus in infants weighing more than 700 g and of postnatal age more than 3 days. Premature low-weight infants are predisposed to hypothermia when transported outside of the thermo-neutral environment. At our institution, 90% of extremely preterm low-weight infants developed transient moderate hypothermia in the cardiac catheterisation suite. METHODS: We conducted a study testing multiple hypotheses aimed at preventing hypothermia in the cardiac catheterisation suite. Interventions included increasing ambient room temperature, reducing exposure to cold environment and reducing overall time spent in the remote location. The primary outcome was the proportion of patients who developed transient hypothermia at the start of the procedure in the cardiac catheterisation suite. The secondary measures included mean core body temperature at four different instances, as well as anaesthesia time, procedure time and radiation exposure. RESULTS: During the study period, 10 patients were enrolled in each group. The postintervention group saw a reduction in transient hypothermia from 90% to 40% (absolute risk reduction 50%, p=0.02). Data analysis showed an improvement in mean core body temperature (35.4°C vs 36.4°C, p<0.01) as well as a smaller percentage drop in temperature (4% vs 1.3%, p<0.01) between the two groups, both of which were statistically significant. The anaesthesia time, procedure time and radiation exposure reduced between the two groups. CONCLUSION: The application of the interventions reduced hypothermia in this high-risk population. The implementation of a protocol with collaboration of a multidisciplinary team is indispensable in providing optimal care to extremely preterm infants.

Battlefield Acupuncture Use for Perioperative Anesthesia in Veterans Affairs Surgical Patients: A Single-Center Randomized Controlled Trial.

Introduction: The risks from opioid use are well known in and mandate nonpharmacological modalities for the management of postoperative pain. The aim of this study was to investigate the effectiveness of battlefield acupuncture (BFA) as an adjunct therapy for postoperative pain in U.S. veteran patients undergoing major surgery under general anesthesia. Methods: Patients undergoing major surgery performed under general anesthesia from June 2017 to June 2018 were enrolled in the study. Patients were randomly assigned to receive either BFA or sham acupuncture. Outcomes such as pain intensity measured by visual analog scale score, opioid consumption, and the incidence of analgesia-related adverse effects were compared between the study groups. Results: A total of 72 subjects were included in this study (36 subjects in each study group). The median 24-h opioid postoperative consumption measured in morphine milligram equivalent (MME) was lower in the BFA group compared to the sham acupuncture group (18.3 [±12.2] MME vs. 38.6 [±15.9] MME, p < 0.001). Pain intensity reported by patients at 6, 12, 18, and 24 h postoperatively was lower in the BFA group compared to the sham acupuncture group. The incidence of postsurgical nausea and vomiting was lower in patients receiving BFA compared to patients receiving sham acupuncture. There were no intergroup differences in terms of postoperative anxiety or hospital length of stay. Conclusion: The results from this study reveal the potential clinical benefits of using BFA for reducing pain intensity and opioid requirements in surgical patients.

A Comparison of Neuraxial and General Anesthesia for Thirty-Day Postoperative Outcomes in United States Veterans Undergoing Total Knee Arthroplasty.

BACKGROUND: The aim of this study is to investigate which anesthetic technique is superior on 30-day outcomes after primary total knee arthroplasty (TKA) in United States veteran patients. To our knowledge, this is the first account from the Veterans Health Administration comparing the effects of different anesthesia modalities in patients undergoing TKA. METHODS: The Veterans Affairs Surgical Quality Improvement Program database was utilized to analyze patients undergoing primary TKA during the period of 2008-2015. Subjects were divided into 2 cohorts based on the method of surgical anesthesia used: general anesthesia or neuraxial anesthesia. Propensity score matching was utilized to avoid possible selection bias between the 2 cohorts when assessing patient demographics and comorbidities. The 2 groups were analyzed for 30-day postoperative complications, using multivariable logistic regression techniques to evaluate independent associations between anesthetic method and postoperative outcomes. RESULTS: All Veterans Affairs patients undergoing primary TKA under general anesthesia (n = 32,363) and neuraxial anesthesia (n = 14,395) within the study period were included in this study. Following propensity score matching, multivariable analysis revealed significantly lower risks of cardiovascular (adjusted odds ratio [AOR] 0.74, 95% confidence interval [CI] 0.6-0.88, P < .001), respiratory (AOR 0.75, 95% CI 0.57-0.97, P = .03), and renal complications (AOR 0.62, 95% CI 0.4-0.9, P = .01) in patients receiving neuraxial anesthesia compared to those receiving general anesthesia. Neuraxial anesthesia was also associated with reduced hospital stay and lower odds of prolonged hospitalization (AOR 0.85, 95% CI 0.8-0.9, P < .001). CONCLUSION: Veteran patients undergoing TKA under neuraxial anesthesia had reduced postoperative complications and decreased hospitalization stay compared to patients undergoing general anesthesia.

Down-Time During Work-Time.

An idle body can harbor an idle mind that often brews something appalling in emptiness. Refreshing one's mind during Down-Time (Me-Time) with "harmless" activities is a must whether at home or at the workplace.

A Novel Process Audit for Standardized Perioperative Handoff Protocols.

A perioperative handoff protocol provides a standardized delivery of communication during a handoff that occurs from the operating room to the postanestheisa care unit or ICU. The protocol's success is dependent, in part, on its continued proper use over time. A novel process audit was developed to help ensure that a perioperative handoff protocol is used accurately and appropriately over time. The Audit Observation Form is used for the Audit Phase of the process audit, while the Audit Averages Form is used for the Data Analysis Phase. Employing minimal resources and using quantitative methods, the process audit provides the necessary means to evaluate the proper execution of any perioperative handoff protocol.

Does exposure to inhalation anesthesia gases change the ratio of X-bearing sperms and Y-bearing Sperms? A worth exploring project into an uncharted domain.

According to recent surveys performed in United States and India, anesthesia care providers were observed to have sired female offspring in a higher proportion than male offspring as their firstborn progeny; however, the reasons for the skew are not clear. Our hypothesis is that the underlying biological evidence may be elucidated by unraveling differences (if any) between the concentrations of X-bearing sperms and Y-bearing sperms in the semen samples obtained from males exposed to varied levels of anesthetics in their lifetimes. Therefore, the objectives of the envisaged study would be to conduct a three-stage investigative study on in-vitro human semen samples to determine (a) X-bearing sperms and Y-bearing sperms concentrations' ratio in male pediatric anesthesia care providers' semen samples, (b) changes in X-bearing sperms and Y-bearing sperms concentrations' ratios between the pre-rotation and post-rotation semen samples of male medical student volunteers/observers, and (c) changes in X-bearing sperms and Y-bearing sperms concentrations' ratios between the pre-operative and post-operative day-3 semen samples of male patients presenting for outpatient procedures under inhalational anesthesia. The expected outcomes would be (a) linear and positive correlation of the anesthetic gas usage (exposure) with increased X-bearing sperms/Y-bearing sperms ratio in post-anesthesia day 3 sample as compared to the baseline preoperative sample, (b) linear and positive correlation of the anesthetic gas usage (exposure) with increased X-bearing sperms/Y-bearing sperms ratio in post-rotation sample as compared to the baseline sample, and (c) observation of high X-bearing sperms/Y-bearing sperms ratio in the pediatric anesthesia care providers. In summary, effects (if any) of occupational or personal exposure to inhalational anesthetic gases on the X-bearing sperms and Y-bearing sperms ratio is a worthy project wherein lots of questions that have arisen over decades could find the path to their definitive answers, based on envisaged laboratory investigations into this uncharted domain.

Effects of Circuit Leak Development Over Time and Response During Low-Flow Volume and Pressure-Controlled Ventilation.

Study Objective: To study the effects of circuit leak development over time and response during volume and pressure controlled ventilation using low flow in human patient simulator and to examine the minimum fresh gas flow needed to compensate for such a leak. Design/Setting: Prospective study using a patient Simulation Lab at Wayne State University. Measurements: A human patient simulator was endotracheally intubated. The endotracheal tube (ETT) was connected to the Datex-Ohmeda AS/3 Anesthesia machine. The tidal volume was set to 500ml in the volume controlled trial and the pressure to 6cm H2O in the pressure controlled trial. A hole was created in each experiment placed 10 cm after the inspiratory valve. Leaks were simulated from holes using 4 different needle diameters: 25, 21, 18 and 16G. A series of data were collected using fresh gas flow at 4 different flow rates (0.5, 1, 1.5 and 2 liters.min-1). Data was measured at different time points (baseline, 1, 3 and 5 minutes) in the series of simulated leaking breathing circuits. Results: Leak alarms were only detected with 16G hole at 5 minutes in the volume control mode versus leaks at 3 minutes with 16G hole and at 5 minutes with 18G hole in the pressure control mode. Conclusion: When a very low flow of 0.5 L/min is used, volume control is safer than pressure control modes.

RESIDENT IMPLEMENTATION OF THE 2007 ACC/AHA GUIDELINES ON PREOPERATIVE CARDIAC EVALUATION IN NON-CARDIAC SURGERY PATIENTS: IS CLINICAL EXPERIENCE ENOUGH?

BACKGROUND: Preoperative evaluation of surgical patients is important, as perioperative complications are associated with increased mortality. Specialties including anesthesiology, internal medicine, cardiology, and surgery are involved in the evaluation and management of these patients. This institutional study investigated the residents' knowledge of the 2007 American College of Cardiology/American Heart Association (ACC/AHA) guidelines on perioperative evaluation of patients undergoing non-cardiac surgery. METHODS: This pilot study used a web-based survey questionnaire to assess resident's knowledge of the 2007 ACC/AHA guidelines through individual steps and corresponding branch point(s) in twelve clinical scenarios. Additionally, residents were asked if they were aware of, or if they had received lectures on ACC/AHA guidelines. Staff anesthesiologists with training in cardiac and intensive care medicine validated the scenarios. RESULTS: A total of 104 resident participants were surveyed including 35 anesthesiology residents, 41 internal medicine residents, 20 surgery residents, and 8 cardiology fellows. Awareness of the 2007 ACC/AHA guidelines by specialty was: anesthesiology (85%), internal medicine (97.6%), cardiology (100%), and surgery (70%). Only 54.3% of anesthesiology, 31.7% of internal medicine, 100% of cardiology, and 10% of surgery residents stated they received lectures. The overall mean score achieved on the eleven scenarios was 50.4% for anesthesiology, 47.0% for internal medicine, 55.7% for cardiology, and 42.3% for surgery. CONCLUSIONS: Although the majority of residents were aware of the 2007 ACC/AHA guidelines, fewer received lectures and regardless of specialty, implementation of these guidelines was poor. There exists significant room for improvement in the understanding of preoperative assessment of non-cardiac surgery patients.

RENAL PROTECTION IN THE CARDIAC SURGERY PATIENT: PERI-OPERATIVE SODIUM BICARBONATE INFUSION (POSBI) OR NOT?

BACKGROUND: Acute renal failure following cardiac surgery is not uncommon and carries a high level of morbidity and mortality. The aim of our study was to determine whether perioperative sodium bicarbonate infusion (POSBI) would decrease acute kidney injury in cardiac surgery patients and improve post-operative outcomes. METHODS: A retrospective analysis of 318 cardiac surgery patients from 2008-2011 was performed. Clinical parameters were compared in patients receiving POSBI versus sodium chloride. Serum creatinine levels were measured in the first five post-operative days. The primary outcome measured was the number of patients developing post-operative renal injury. Secondary outcomes included three-month mortality, intensive care unit and hospital length of stay. RESULTS: Patients given POSBI showed no significant differences compared to the normal saline cohort in regards to increases in serum creatinine [< 25% rise in Cr: 93% vs 94%; > 25% rise in Cr: 6% vs 6%; > 50% rise in Cr: 1% vs 1%; > 100% rise in Cr: 1% vs 0%, all with p-value > 0.99]. There were fewer patients with AKIN stage 1 renal failure receiving POSBI [8% vs 28%, p = 0.02] however there was no difference between POSBI and sodium chloride cohorts in AKIN stages 2 and 3 renal failure. Mortality, duration of hospitalization and ICU stay were not statistically significant. CONCLUSIONS: POSBI resulted in fewer patients developing AKIN stage 1 renal failure. Despite this, there appears to be little benefit in the prevention of acute kidney injury after 48 hours or mortality reduction in cardiac surgery patients.

CONSUMPTION TRENDS OF RESCUE ANTI-PSYCHOTICS FOR DELIRIUM IN INTENSIVE CARE UNITS (ICU DELIRIUM) SHOW INFLUENCE OF CORRESPONDING LUNAR PHASE CYCLES: A RETROSPECTIVE AUDIT STUDY FROM ACADEMIC UNIVERSITY HOSPITAL IN THE UNITED STATES.

BACKGROUND: The etiology of delirium in intensive care units (ICU) is usually multi-factorial. There is common "myth" that lunar phases affect human body especially human brains (and minds). OBJECTIVE: In the absence of any pre-existing studies in ICU patients, the current retrospective study was planned to investigate whether lunar phases play any role in ICU delirium by assessing if lunar phases correlate with prevalence of ICU delirium as judged by the corresponding consumptions of rescue anti-psychotics used for delirium in ICU. MATERIALS AND METHODS: After institutional review board approval with waived consent, the daily census of ICU patients from the administrative records was accessed at an academic university's Non-Cancer Hospital in a Metropolitan City of United States. Thereafter, the ICU pharmacy's electronic database was accessed to obtain data on the use of haloperidol and quetiapine over the two time periods for patients aged 18 years or above. Subsequently the data was analyzed for whether the consumption of haloperidol or quetiapine followed any trends corresponding to the lunar phase cycles. RESULTS: A total of 5382 pharmacy records of haloperidol equivalent administrations were analyzed for this study. The cumulative prevalence of incidents of haloperidol equivalent administrations peaked around the full moon period and troughed around the new moon period. As compared to male patients, female patients followed much more uniform trends of haloperidol equivalent administrations' incidents which peaked around the full moon period and troughed around the new moon period. Further sub-analysis of 70-lunar cycles across the various solar months of the total 68-month study period revealed that haloperidol equivalent administrations' incidents peaked around the full moon periods during the months of November-December and around the new moon periods during the month of July which all are interestingly the major holiday months (a potential confounding factor) in the United States. CONCLUSION: Consumption trends of rescue anti-psychotics for ICU delirium revealed an influence by lunar phase cycles particularly that of full moon periods on female patients in the ICU.

Intraoperative patient information handover between anesthesia providers.

Currently, no reported studies have evaluated intraoperative handover among anesthesia providers. Studies on anesthetic handover in the US recovery room setting observed that handover processes are insufficient and, in many instances, significant intraoperative events are disregarded. An online survey tool was sent to anesthesia providers at US anesthesia residency programs nationwide (120 out of the 132 US programs encompassing around 4500 residents and their academic MDAs) and a smaller survey selection of CRNAs (10 institutions about 300 CRNAs in the metropolitan area of Detroit, MI, USA) to collect information on handover practices. The response rate to this survey (n = 216) was comprised of approximately 5% (n = 71) of the resident population in US anesthesia programs, 5% (n = 87) of MDAs , and 20% (n = 58) of the CRNAs. Out of all respondents (n = 212), 49.1 % had no hand-over protocol at their institution and 88% of respondents who did have institutional handover protocols believed them insufficient for effective patient handover. In addiiton, 84.8% of all responders reported situations where there was insufficient information received during a patient handover. Only 7% of the respondents reported never experiencing complications or mismanagement due to poor or incomplete hand-overs. In contrast, 60% reported rarely having complications, 31% reported sometimes having complications, and 3% reported frequent complications. In conclusion, handover transition of patient care is a vulnerable and potentially life-threatening event in the operating room. Our preliminary study suggests that current intraoperatvive handover practices among anesthesia providers are suboptimal and that national patient handover guidelines are required to improve patient safety.

STOP-Bang and prediction of difficult airway in obese patients.

STUDY OBJECTIVE: To determine if a high score (≥ 3) on the STOP-Bang screening questionnaire for obstructive sleep apnea (OSA) predicts whether obese patients are at high risk for OSA and increased risk of difficult airway. DESIGN: Prospective, questionnaire-based clinical assessment. SETTING: University-affiliated hospital. PATIENTS: 127 ASA physical status 2 and 3 patients, who were scheduled for elective bariatric surgery. INTERVENTIONS: Patients were allocated to three groups. Group 1 patients had a previous history of OSA, Group 2 patients had no history of OSA but did have a high STOP-Bang score (≥ 3), and Group 3 patients had no history of OSA but did have a low STOP-Bang score (< 3). Groups 2 and 3 only were assessed using the STOP-Bang questionnaire. After induction and intubation of the patient, an anesthesiologist who was blinded to the three study group allocations completed an airway questionnaire on the three study groups. MEASUREMENTS: The frequency of difficult airway, difficult mask ventilation with or without muscle relaxation, poor visualization of the vocal cords, difficulty in blade insertion, and difficult intubation were compared. MAIN RESULTS: The group of patients with high STOP-Bang scores (Group 2) and those patients previously diagnosed with OSA (Group1) showed a higher risk for difficult airway than the patients with low STOP-Bang scores (Group 3; P < 0.001). CONCLUSION: The STOP-Bang score may be used as an effective predictor of difficult airway in obese patients. Obese surgical patients with unknown/undiagnosed OSA status should be evaluated using the STOP-Bang questionnaire score.

Delayed vocal fold paralysis after continuous interscalene level brachial plexus block with catheter placement: a case report.

We report an incident of delayed onset of true vocal fold paralysis with continuous interscalene brachial plexus block. A 51 year old woman underwent left shoulder manipulation and lysis of adhesions with fluoroscopy and general anesthesia. An interscalene brachial plexus block was performed and a catheter with a continuous infusion pump was placed for postoperative pain control. Following hospital discharge, approximately 8 hours after the initial catheter bolus the patient developed hoarseness, dysphagia, and dyspnea, secondary to left vocal fold palsy. The patient was admitted for observation and the catheter was discontinued with no intubation required. By the next morning, the patient's dysphagia and dyspnea had resolved and her hoarseness improved.

Effective low dosage of mepivacaine in ultrasound-guided axillary nerve block: a double-blinded, randomized clinical trial of efficacy in patients undergoing distal upper extremity surgery.

STUDY OBJECTIVE: To evaluate two low-dose volumes (20 mL or 30 mL) of 1.5% mepivacaine solution used for ultrasound-guided axillary blockade for outpatients undergoing distal upper limb surgery. DESIGN: Prospective, double-blinded randomized study. SETTING: Outpatient surgical setting of a university-affiliated hospital. PATIENTS: 64 adult, ASA physical status 1, 2, and 3 patients, aged 28-46 years, scheduled for upper limb surgery. INTERVENTIONS: Patients were randomized to two groups to receive either 20 mL of 1.5% mepivacaine solution (n=31) or 30 mL of 1.5% mepivacaine solution (n=33) for ultrasound-guided axillary plexus blockade. MEASUREMENTS: Block duration, proportion of surgical and functional successful blocks, onset of sensory and motor blockade measured from 0 to 30 minutes following final needle extraction, total amount of preoperative sedative (midazolam), and intraoperative propofol administered were recorded. MAIN RESULTS: Following axillary plexus blockade, neither patient group showed any statistically significant difference in the percentage of functionally successful blockade (30 mL, 100%: 20 mL, 97%; P = 0.48), surgically successful blockade (30 mL, 100%; 20 mL, 94%; P = 0.23), cumulative sensory or motor blockade surgical time, block performance time, preoperative midazolam use, or intraoperative propofol use. CONCLUSION: Low volumes (30 mL or 20 mL) of 1.5% mepivacaine provides satisfactory anesthesia for ambulatory distal upper limb surgery with no significant difference in clinical outcomes.

Ketamine reverses stress-induced depression-like behavior and increased GABA levels in the anterior cingulate: an 11.7 T 1H-MRS study in rats.

Gamma-aminobutyric acid (GABA) is the major inhibitory amino acid neurotransmitter in the brain and is primarily responsible for modulating excitatory tone. Clinical neuroimaging studies show decreased GABA levels in the anterior cingulate of patients with mood disorders, including major depressive disorder. Chronic unpredictable stress (CUS) is an animal model thought to mimic the stressful events that may precipitate clinical depression in humans. In this study male Sprague-Dawley rats were subjected to a modified CUS paradigm that used a random pattern of unpredictable stressors twice daily for 10 days to explore the early developmental stages of depression-like endophenotypes. Control rats were handled daily for 10 days. Some rats from each treatment group received an injection of ketamine (40 mg/kg) after the final stressor. One day following the final stressor rats were tested for behavioral effects in the forced swim test and then euthanized to collect trunk blood and anterior cingulate brain samples. GABA levels were measured in anterior cingulate samples ex vivo using proton magnetic resonance spectroscopy ((1)H-MRS) at 11.7 T. Animals subjected to CUS had lower body weights, higher levels of blood corticosterone, and increased immobility in the forced swim test; all of which suggest that the stress paradigm induced a depression-like phenotype. GABA levels in the anterior cingulate were significantly increased in the stressed animals compared to controls. Administration of ketamine on the last day of treatment blunted the depression-like behavior and increased GABA levels in the anterior cingulate following CUS. These data indicate that stress disrupts GABAergic signaling, which may over time lead to symptoms of depression and ultimately lower basal levels of cortical (1)H-MRS GABA that are seen in humans with depression. Furthermore, the data suggests that ketamine modulates cortical GABA levels as a mechanism of its antidepressant activity.

Firstborn offspring sex ratio is skewed towards female offspring in anesthesia care providers: A questionnaire-based nationwide study from United States.

BACKGROUND: A parental occupation such as anesthesia care provider can involve exposure of the parent to various chemicals in the work environment and has been correlated to skewed offspring sex ratios. OBJECTIVES: The objective was to conduct a nation-wide survey to observe (a) whether firstborn offspring sex ratio (OSR) in anesthesia providers is skewed towards increased female offspring, and (b) to identify potential factors influencing firstborn OSR, particularly those relating to the peri-conceptional practice of inhalational anesthesia induction among anesthesia providers. MATERIALS AND METHODS: After institutional review board approval, a questionnaire was uploaded on SurveyMonkey and sent to anesthesia providers through their program coordinators in United States (US) to complete the survey. RESULTS: The current US national total-population sex ratio is 0.97 male (s)/female with an at-birth sex ratio of 1.05 male (s)/female; comparatively, the results from anesthesia providers' survey respondents (n = 314) were a total OSR of 0.93 male (s)/female (P = 0.61) with firstborn OSR 0.82 male (s)/female (a 6% increase in female offspring; P = 0.03), respectively. The only significant peri-conceptional factor related to anesthesia providers' firstborn OSR's skew was inhalational induction practice by anesthesia care provider favoring female offspring (P < 0.01). CONCLUSION: Based on the results of this limited survey, it can be concluded that anesthesia care providers who practice inhalation induction of anesthesia during the peri-conceptional period are significantly more likely to have firstborn female offspring.

Phantom shocks unmasked: clinical data and proposed mechanism of memory reactivation of past traumatic shocks in patients with implantable cardioverter defibrillators.

BACKGROUND: Implantable cardioverter defibrillators (ICD), despite an unequivocal clinical benefit, are known to have a complex psychosocial impact on the patients. ICD shocks and the resultant psychobiological changes are known to contribute to increased levels of anxiety, depression, and post-shock stress symptoms in these patients. Phantom shock is a patient-reported perception of an ICD shock in the absence of any actual shock; however, its pathophysiological understanding is poor. METHODS: A retrospective chart review of the University hospital ICD patients' database from June 2006 to April 2010 was conducted. A total of 38 patients with documented phantom shocks as cases and 76 age- and sex-matched patients with no phantom shocks as controls were selected from the database. Patient characteristics were analyzed for their potential association with the occurrence of phantom shocks. RESULTS: Phantom shock patients had higher prevalence of documented depression (31.6%), anxiety (23.7%), and cocaine use (42.1%). Additionally, patients who had previous ICD shock storms were more likely to have phantom shocks (39.5%; p = 0.001). More importantly, no phantom shocks were reported in patients who did not receive defibrillation threshold testing or past ICD shock storms. CONCLUSIONS: Phantom shocks are primarily observed in ICD patients who had prior exposure to traumatic device shocks and are more common in patients with a history of depression, anxiety, or substance abuse. A pathophysiological mechanism is proposed as a guide to potential prevention.