Serum Levels of Bupivacaine After Bilateral Ultrasound-Guided Deep Parasternal Intercostal Plane Block in Cardiac Surgery with Median Sternotomy.

OBJECTIVE: To evaluate systemic levels of bupivacaine after bilateral ultrasound-guided deep parasternal intercostal plan (PIP) block in cardiac surgical patients undergoing median sternotomy. DESIGN: Prospective, observational study SETTING: Single institution; academic university hospital PARTICIPANTS: Twenty-eight adult patients undergoing cardiac surgery with median sternotomy received a PIP block with 2.5 mg/kg bupivacaine with or without dexamethasone and dexmedetomidine. MEASUREMENTS: Arterial blood samples were analyzed for total serum bupivacaine concentration at 5, 15, 30, 45, 60, 90, 120, and 150 minutes after placement of PIP. Local anesthetic volume, local anesthetic adjuncts, time to extubation, postoperative pain scores, and opioid consumption were recorded. MAIN RESULTS: The mean peak bupivacaine concentration was 0.60 ± 0.62 µg/mL, and the mean time to maximum concentration (Tmax) was 16.92 ± 12.97 minutes. Two patients (7.1%) had a concentration >2.0 µg/mL within 15 minutes of block placement. The mean Tmax of bupivacaine was significantly greater in patients who did not receive additives compared to those patients who did (22.86 ± 14.77 minutes v 10.0 ± 5.22 minutes; p = .004). The times to extubation and postoperative pain were not improved with additives. CONCLUSIONS: Bilateral PIP placed at the end of cardiac surgery resulted in low systemic bupivacaine levels. The inclusion of additives shortened Tmax without improving outcome.

Hemodynamic Monitoring In The Cardiac Surgical Patient: Comparison of Three Arterial Catheters.

OBJECTIVE: Systemic systolic (SAP) and mean (MAP) arterial pressure monitoring is the cornerstone in hemodynamic management of the cardiac surgical patient, and the radial artery is the most common site of catheter placement. The present study compared 3 different arterial line procedures. It is hypothesized that a 20-G 12.7- cm catheter inserted into the radial artery will be equal to a 20-G 12.7- cm angiocath placed in the brachial artery, and superior to a 20-G 5.00 cm angiocath placed in the radial artery. DESIGN: A prospective randomized control study was performed. SETTING: Single academic university hospital. PARTICIPANTS: Adult patients ≥18 years old undergoing nonemergent cardiac surgery using cardiopulmonary bypass (CPB). INTERVENTIONS: After approval by the Rhode Island Hospital institutional review board, a randomized prospective control study to evaluate 3 different peripheral intraarterial catheter systems was performed: (1) Radial Short (RS): 20-G 5- cm catheter; (2) Radial Long (RL): 20-G 12- cm catheter; and (3) Brachial Long (BL): 20-G 12- cm catheter. MEASUREMENTS AND RESULTS: Gradients between central aortic and peripheral catheters (CA-P) were compared and analyzed before CPB and 2 and 10 minutes after separation from CPB. The placement of femoral arterial lines and administration of vasoactive medications were recorded. After exclusions, 67 BL, 61 RL, and 66 RS patients were compared. Before CPB, CA-P SAP and MAP gradients were not significant among the 3 groups. Two minutes after CPB, the CA-P SAP gradient was significant for the RS group (p = 0.005) and insignificant for BL (p = 0.47) and RL (p = 0.39). Two-group analysis revealed that CA-P SAP gradients are similar between BL and RL (p = 0.84), both of which were superior to RS (p = 0.02 and p = 0.04, respectively). At 10 minutes after CPB, the CA-P SAP gradient for RS remained significant (p = 0.004) and similar to the gradient at 2 minutes. The CA-P SAP gradients increased from 2 to 10 minutes for BL (p = 0.13) and RL (p = 0.06). Two minutes after CPB, the CA-P MAP gradients were significant for the BL (p = 0.003), RL (p < 0.0001), and RS (p < 0.0001) groups. Two-group analysis revealed that the CA-P MAP gradients were lower for the BL group compared with the RL (p = 0.054) and RS (p< 0.05) groups. Ten minutes after CPB, the CA-P MAP gradients in the RL and RS groups remained significant (p < 0.0001) and both greater than the BL group (p = 0.002). A femoral arterial line was placed more frequently in the RS group (8/66 = 12.1%) than in the RL group (3/61 = 4.9%) and the BL group (2/67 = 3.0%). Vasopressin was administered significantly more frequently in the RS group. CONCLUSION: Regarding CA-P SAP gradients, the RL group performed equally to the BL group, both being superior to RS. Regarding CA-P MAP gradients, BL was superior to RL and RS. Clinically, femoral line placement and vasopressin administration were fewer for the BL and RL groups when compared with the RS group. This study demonstrated the benefits of a long (12.7 cm) 20- G angiocath placed in the radial artery.

The impact of hypoalbuminemia on postoperative outcomes after outpatient surgery: a national analysis of the NSQIP database.

PURPOSE: Hypoalbuminemia has been described as a modifiable factor to optimize postoperative outcomes after major inpatient surgeries. Nevertheless, the role of hypoalbuminemia on outpatient procedures is not well defined. The purpose of this study was to examine the impact of hypoalbuminemia on postoperative outcomes of patients undergoing low-risk outpatient surgery. METHODS: Patients were extracted from the American College of Surgeons National Surgical Quality Improvement Program database who had outpatient surgery from 2018 and recorded preoperative albumin levels. The primary outcome was a composite of any major complications including: 1) unplanned intubation, 2) pulmonary embolism, 3) ventilator use > 48 hr, 4) progressive renal failure, 5) acute renal failure, 6) stroke/cerebrovascular accident, 7) cardiac arrest, 8) myocardial infarction, 9) sepsis, 10) septic shock, 11) deep venous thrombosis, and 12) transfusion. Death, any infection, and readmissions were secondary outcomes. RESULTS: A total of 65,192 (21%) surgical outpatients had albumin collected preoperatively and 3,704 (1.2%) patients had levels below 3.5 g⋅dL-1. In the albumin cohort, 394/65,192 (0.6%) patients had a major medical complication and 68/65,192 (0.1%) patients died within 30 days after surgery. Albumin values < 3.5 g⋅dL-1 were associated with major complications (adjusted odds ratio [aOR], 1.92; 95% confidence interval [CI], 1.44 to 2.57; P < 0.001; death-adjusted OR, 3.03; 95% CI, 1.72 to 5.34; P < 0.001); any infection (aOR, 1.49; 95% CI, 1.23 to 1.82; P < 0.001); and readmissions (aOR, 1.82; 95% CI, 1.56 to 2.14; P < 0.001). In addition, when evaluated as a continuous variable in a multivariate analysis, for each increase in albumin of 0.10 g⋅dL-1, there was an associated reduction of major complications (aOR, 0.94; 95% CI, 0.92 to 0.96; P < 0.001). CONCLUSIONS: Hypoalbuminemia is associated with major complications and death in outpatient surgery. Since hypoalbuminemia is a potential modifiable intervention, future clinical trials to evaluate the impact of optimizing preoperative albumin levels before outpatient surgery are warranted.

RéSUMé: OBJECTIF: L'hypoalbuminémie a été décrite comme un facteur modifiable pour optimiser les issues postopératoires après des chirurgies hospitalières majeures. Néanmoins, le rôle de l'hypoalbuminémie dans les interventions ambulatoires n'est pas bien défini. L'objectif de cette étude était d'examiner l'impact de l'hypoalbuminémie sur les issues postopératoires des patients bénéficiant d'une chirurgie ambulatoire à faible risque. MéTHODE: Les patients ayant bénéficié d'une chirurgie ambulatoire à partir de 2018 et pour lesquels les taux d'albumine préopératoire ont été enregistrés ont été extraits de la base de données américaine du programme national d'amélioration de la qualité chirurgicale (NSQIP) de l'American College of Surgeons. Le critère d'évaluation principal était un composite de toutes les complications majeures, y compris : 1) intubation non planifiée, 2) embolie pulmonaire, 3) utilisation d'un ventilateur > 48 h, 4) insuffisance rénale progressive, 5) insuffisance rénale aiguë, 6) accident vasculaire cérébral, 7) arrêt cardiaque, 8) infarctus du myocarde, 9) sepsis, 10) choc septique, 11) thrombose veineuse profonde, et 12) transfusion. Les décès, infections et réadmissions constituaient des critères d'évaluation secondaires. RéSULTATS: Au total, les taux d'albumine ont été prélevés chez 65 192 (21 %) patients chirurgicaux ambulatoires avant l'opération et 3704 (1,2 %) patients avaient des taux inférieurs à 3,5 g⋅dL-1. Dans la cohorte albumine, 394 / 65 192 (0,6 %) patients ont eu une complication médicale majeure et 68 / 65 192 (0,1%) patients sont décédés dans les 30 jours suivant la chirurgie. Des valeurs d'albumine < 3,5 g⋅dL-1 étaient associées à des complications majeures (rapport de cotes ajusté [RCA]), 1,92 ; intervalle de confiance [IC] à 95 %, 1,44 à 2,57; P < 0,001; RC ajusté en fonction du décès, 3,03; IC 95 %, 1,72 à 5,34; P < 0,001); infections (RCA, 1,49; IC 95 %, 1,23 à 1,82; P < 0,001); et réadmissions (RCA, 1,82; IC 95 %, 1,56 à 2,14; P < 0,001). De plus, lorsque le taux d'albumine était évalué comme variable continue dans une analyse multivariée, pour chaque augmentation de l'albumine de 0,10 g⋅dL-1, il y avait une réduction associée des complications majeures (RCA, 0,94; IC 95 %, 0,92 à 0,96; P < 0,001). CONCLUSION: L'hypoalbuminémie est associée à des complications majeures et au décès en chirurgie ambulatoire. Étant donné que l'hypoalbuminémie est une intervention potentiellement modifiable, de futures études cliniques visant à évaluer l'impact de l'optimisation des taux préopératoires d'albumine avant une chirurgie ambulatoire sont nécessaires.

Early Postoperative Outcomes of Super Morbid Obese Compared to Morbid Obese Patients After Ambulatory Surgery Under General Anesthesia: A Propensity-Matched Analysis of a National Database.

BACKGROUND: Patients with body mass index (BMI) ≥50 kg/m2, defined as super morbid obesity, represent the fastest growing segment of patients with obesity in the United States. It is currently unknown if super morbid obese patients are at greater odds than morbid obese patients for poor outcomes after outpatient surgery. The main objective of the current investigation is to assess if super morbid obese patients are at increased odds for postoperative complications after outpatient surgery when compared to morbid obese patients. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2017 to 2018 was queried to extract and compare patients who underwent outpatient surgery and were defined as either morbidly obese (BMI >40 and <50 kg/m2) or super morbidly obese (BMI ≥50 kg/m2). The primary outcome was the occurrence of medical adverse events within 72 hours of discharge. In addition, we also examine death and readmissions as secondary outcomes. A propensity-matched analysis was used to evaluate the association of BMI ≥50 kg/m2 versus BMI between 40 and 50 kg/m2 and the outcomes. RESULTS: A total of 661,729 outpatient surgeries were included in the 2017-2018 NSQIP database. Of those, 7160 with a BMI ≥50 kg/m2 were successfully matched to 7160 with a BMI <50 and ≥40 kg/m2. After matching, 17 of 7160 (0.24%) super morbid obese patients had 3-day medical complications compared to 15 of 7160 (0.21%) morbid obese patients (odds ratio [OR; 95% confidence interval {CI}] = 1.13 [0.57-2.27], P = .72). The rate of 3-day surgical complications in super morbid obese patients was also not different from morbid obese patients. Thirty-five of 7160 (0.48%) super morbid obese patients were readmitted within 3 days, compared to 33 of 7160 (0.46%) morbid obese patients (OR [95% CI] = 1.06 [0.66-1.71], P = .80). When evaluated in a multivariable analysis as a continuous variable (1 unit increase in BMI) in all patients, BMI ≥40 kg/m2 was not significantly associated with overall medical complications (OR [95% CI] = 1.00 [0.98-1.04], P = .87), overall surgical complication (OR [95% CI] = 1.02 [0.98-1.06], P = .23), or readmissions (OR [95% CI] = 0.99 [0.97-1.02], P = .8). CONCLUSIONS: Super morbid obesity is not associated with higher rates of early postoperative complications when compared to morbid obese patients. Specifically, early pulmonary complications were very low after outpatient surgery. Super morbid obese patients should not be excluded from outpatient procedures based on a BMI cutoff alone.

An appraisal of published clinical guidelines in anesthesiology practice using the AGREE II instrument.

PURPOSE: Clinical practice guidelines are developed to provide physicians with appraised scientific evidence and enhance their medical decision-making process. Poorly developed guidelines can have a negative impact on patient care, but the quality of clinical guidelines has not been evaluated in anesthesiology practice. METHODS: We evaluated the quality of clinical practice guidelines in anesthesiology retrieved from PubMed, Scopus, Cochrane Library, and Embase databases from August 2013 to August 2018 using a validated appraisal instrument. Exclusion criteria excluded consensus statements, editorials, non-clinical/legal-themed manuscripts, institutional protocols, research methods, and chronic pain and surgical technique guidelines. PRINCIPAL FINDINGS: A total of 96 clinical practice guidelines were included in the analysis. Seventy-one out of 96 (74%; 95% confidence interval, 65 to 83) guidelines had overall quality scores lower or equal to 5 and could not be recommended as published. Higher quality guidelines (overall score greater than 5) were published in journals with higher median [interquartile range] impact factors than lower quality guidelines (4.0 [3.5-6.5] vs 3.8 [2.3-4.7]; P = 0.02). The publication of a higher quality guideline was not associated with the year that the guideline was published or if the guideline was published by a society. CONCLUSIONS: The overall quality of most guidelines relevant to the practice of anesthesiology were poor, and the domains applicability and rigor of development rated particularly low. Future groups developing clinical guidelines should consider using methodological support to improve the quality of guidelines relevant to the practice of anesthesiology.

RéSUMé: OBJECTIF: Les lignes directrices de pratique clinique sont élaborées afin de fournir aux médecins des données probantes et d'améliorer leur processus de prise de décision médicale. Des lignes directrices mal élaborées peuvent avoir un impact négatif sur les soins aux patients, mais la qualité des lignes directrices cliniques n'a pas été évaluée en anesthésiologie. MéTHODE: Nous avons évalué la qualité des directives pour la pratique clinique de l'anesthésiologie extraites des bases de données PubMed, Scopus, Cochrane Library et Embase entre le mois d'août 2013 et le mois d'août 2018 à l'aide d'un instrument d'évaluation validé. Étaient exclus selon nos critères les déclarations de consensus, les éditoriaux, les manuscrits non cliniques/juridiques, les protocoles institutionnels, les méthodes de recherche et les lignes directrices sur la douleur chronique et les techniques chirurgicales. CONSTATATIONS PRINCIPALES: Au total, 96 lignes directrices sur la pratique clinique ont été incluses dans notre analyse. Soixante et onze lignes directrices sur 96 (74 %; intervalle de confiance de 95 %, 65 à 83) avaient des scores de qualité globaux inférieurs ou égaux à 5 et ne pouvaient pas être recommandées telles que publiées. Les lignes directrices de meilleure qualité (score global supérieur à 5) ont été publiées dans des revues ayant des facteurs d'impact médians [écart interquartile] plus élevés que les lignes directrices de qualité inférieure (4,0 [3,5-6,5] vs 3,8 [2,3­4,7]; P = 0,02). La publication d'une ligne directrice de meilleure qualité n'a pas été associée à l'année de publication de la ligne directrice ni à sa publication par une société. CONCLUSION: La qualité globale de la plupart des lignes directrices pertinentes à la pratique de l'anesthésiologie était médiocre, et les domaines d'applicabilité et de la rigueur de mise au point ont été évalués comme étant particulièrement faibles. Les futurs groupes élaborant des lignes directrices cliniques devraient envisager d'utiliser un soutien méthodologique pour améliorer la qualité des lignes directrices pertinentes à la pratique de l'anesthésiologie.

Spinal versus general anesthesia for patients undergoing outpatient total knee arthroplasty: a national propensity matched analysis of early postoperative outcomes.

BACKGROUND: A comparison of different anesthetic techniques to evaluate short term outcomes has yet to be performed for patients undergoing outpatient knee replacements. The aim of this investigation was to compare short term outcomes of spinal (SA) versus general anesthesia (GA) in patients undergoing outpatient total knee replacements. METHODS: The ACS NSQIP datasets were queried to extract patients who underwent primary, elective, unilateral total knee arthroplasty (TKA) between 2005 and 2018 performed as an outpatient procedure. The primary outcome was a composite score of serious adverse events (SAE). The primary independent variable was the type of anesthesia (e.g., general vs. spinal). RESULTS: A total of 353,970 patients who underwent TKA procedures were identified comprising of 6,339 primary, elective outpatient TKA procedures. Of these, 2,034 patients received GA and 3,540 received SA. A cohort of 1,962 patients who underwent outpatient TKA under GA were propensity matched for covariates with patients who underwent outpatient TKA under SA. SAE rates at 72 h after surgery were not greater in patients receiving GA compared to SA (0.92%, 0.66%, P = 0.369). In contrast, minor adverse events were greater in the GA group compared to SA (2.09%, 0.51%), P < 0.001. The rate of postoperative transfusion was greater in the patients receiving GA. CONCLUSIONS: The type of anesthetic technique, general or spinal anesthesia does not alter short term SAEs, readmissions and failure to rescue in patients undergoing outpatient TKR surgery. Recognizing the benefits of SA tailored to the anesthetic management may maximize the clinical benefits in this patient population.

American Society of Anesthesiologists Physical Status Classification as a reliable predictor of postoperative medical complications and mortality following ambulatory surgery: an analysis of 2,089,830 ACS-NSQIP outpatient cases.

BACKGROUND: Seventy percent of surgical procedures are currently performed in the outpatient setting. Although the American Society of Anesthesiologists (ASA) Physical Classification ability to predict risk has been evaluated for in-patient surgeries, an evaluation in outpatient surgeries has yet to be performed. The major goal of the current study is to determine if the ASA classification is an independent predictor for morbidity and mortality for outpatient surgeries. METHODS: The 2005 through 2016 NSQIP Participant Use Data Files were queried to extract all patients scheduled for outpatient surgery. ASA PS class was the primary independent variable of interest. The primary outcome was 30-day medical complications, defined as having one or more of the following postoperative outcomes: (1) deep vein thrombosis, (2) pulmonary embolism, (3) reintubation, (4) failure to wean from ventilator, (5) renal insufficiency, (6) renal failure, (7) stroke, (8) cardiac arrest, (9) myocardial infarction, (10) pneumonia, (11) urinary tract infection, (12) systemic sepsis or septic shock. Mortality was also evaluated as a separate outcome. RESULTS: A total of 2,089,830 cases were included in the study. 24,777 (1.19%) patients had medical complications and 1,701 (0.08%) died within 30 days. ASA PS IV patients had a much greater chance of dying when compared to healthy patients, OR (95%CI) of 89 (55 to 143), P < 0.001. Nonetheless, over 30,000 ASA PS IV patients had surgery in the outpatient setting. Multivariable analysis demonstrated a stepwise independent association between ASA PS class and medical complications (C statistic = 0.70), mortality (C statistic = 0.74) and readmissions (C statistic = 0.67). Risk stratifying ability was maintained across surgical procedures and anesthesia techniques. CONCLUSIONS: ASA PS class is a simple risk stratification tool for surgeries in the outpatient setting. Patients with higher ASA PS classes subsequently developed medical complications or mortality at a greater frequency than patients with lower ASA PS class after outpatient surgery. Our results suggest that the ambulatory setting may not be able to match the needs of high-risk patients.

An evaluation of impact factor bias of clinical trials published in pain journals.

BACKGROUND AND OBJECTIVE: Studies with nonsignificant results are less likely to be published or published in lower impact factor journals. To determine whether a similar phenomenon occurs in pain literature, we explored impact factor bias in peer-reviewed pain journals. METHODS: A PubMed search involving randomized controlled trials in pain journals during 2012 through 2018 was performed. The primary outcome was the publication impact factor. Exclusion criteria included commentaries, editorials, meta-analyses, reviews, and animal studies. The average impact factor for each journal was determined. The primary independent variable was a study with a positive outcome. RESULTS: Of the 9 journals evaluated, 1108 articles met our inclusion criteria and were included in our analysis. The quartiles for the impact factor for the journals included were 2.5, 2.9, and 3.6. A multivariate analysis identified sample size greater than 100, description of a sample size calculation, presence of a stated hypothesis, and presence of sponsorship funding as independent predictors of publication in a journal with greater impact factor. In contrast, positive results were not associated with publication in a greater impact factor journal, even when forced into the model, P = 0.49. CONCLUSIONS: After adjusting for study factors associated with publication, there is no evidence of impact factor bias within the pain literature. The lack of impact factor bias in the pain literature is a positive finding for the field and should benefit scientific development and the clinical care of patients.

The association between labor epidural analgesia and postpartum depression: a systematic review and meta-analysis.

BACKGROUND: Previous studies have demonstrated that appropriate treatment for postoperative pain can lead to improvement in depressive symptoms, however the association between adequate intrapartum pain control and the development of postpartum depression is not clear. The purpose of the study was to examine the effects of labor epidural analgesia and postpartum depression. METHODS: We performed a quantitative systematic review in compliance with the PRISMA statement. We conducted a search of PubMed, Embase, the Cochrane Database of Systematic Reviews and Google Scholar databases. The primary outcome was a positive screen of postpartum depression among women who received labor epidural analgesia up to 3 months into the postpartum period. Meta-analysis was performed using the random effect model. RESULTS: Of the 148 studies available, 9 studies with 4442 patients were included in the analysis. The use of labor analgesia on positive depression screen compared to control revealed no significant effect, OR (95% CI) of 1.02 (0.62 to 1.66, P = 0.94). CONCLUSION: Based on current literature, the use of epidural analgesia for pain relief during labor doesn't appear to affect the likelihood of postpartum depression. Future studies are warranted to further investigate these findings and identity other possible preventative interventions that reduce postpartum depression.

The effect of ultrasound-guided erector spinae plane block on postsurgical pain: a meta-analysis of randomized controlled trials.

BACKGROUND: The effect of erector spinae plane block has been evaluated by clinical trials leading to a diversity of results. The main objective of the current investigation is to compare the analgesic efficacy of erector spinae plane block to no block intervention in patients undergoing surgical procedures. METHODS: We performed a quantitative systematic review of randomized controlled trials in PubMed, Embase, Cochrane Library, and Google Scholar electronic databases from their inception through July 2019. Included trials reported either on opioid consumption or pain scores as postoperative pain outcomes. Methodological quality of included studies was evaluated using Cochrane Collaboration's tool. RESULTS: Thirteen randomized controlled trials evaluating 679 patients across different surgical procedures were included. The aggregated effect of erector spinae plane block on postoperative opioid consumption revealed a significant effect, weighted mean difference of - 8.84 (95% CI: - 12.54 to - 5.14), (P < 0.001) IV mg morphine equivalents. The effect of erector spinae plane block on post surgical pain at 6 h compared to control revealed a significant effect weighted mean difference of - 1.31 (95% CI: - 2.40 to - 0.23), P < 0.02. At 12 h, the weighted mean difference was of - 0.46 (95% CI: - 1.01 to 0.09), P = 0.10. No block related complications were reported. CONCLUSIONS: Our results provide moderate quality evidence that erector spinae plane block is an effective strategy to improve postsurgical analgesia.

Mixing Studies in Patients With Prolonged Activated Partial Thromboplastin Time or Prothrombin Time.

BACKGROUND: Patients presenting for surgery may have isolated or combined prolonged activated partial thromboplastin time (aPTT) and/or prothrombin time (PT). In patients not receiving anticoagulants or with no identifiable cause for abnormal clot formation, a mixing study is performed. The index of circulating anticoagulant (ICA) has been used to predict the presence of an inhibitor, usually a lupus anticoagulant. METHODS: We retrospectively reviewed the results of mixing studies performed at Northwestern Memorial Hospital, between January 1, 2010 and February 29, 2012. We determined the number of samples that normalized or remained prolonged, the clotting factors associated with prolonged test results, and the presence of coagulation inhibitors. We calculated the ICA in the samples with prolonged aPTT and PT to determine its ability to predict a lupus anticoagulant. The primary comparison of interest was the diagnostic utility of the ICA at cutoff values of 11% for predicting the presence of lupus anticoagulant. RESULTS: There were 269 mixing studies performed: 131 samples with prolonged aPTT; 95 with prolonged PT; and 43 with both prolonged aPTT and prolonged PT. Of the samples with a prolonged aPTT, 55 of 131 (42%) normalized, 36 of 131 (27%) partially corrected, and 40 of 131 (31%) remained prolonged. Thirty-three of 95 samples (35%) with prolonged PT normalized, while 62 of 95 (65%) remained prolonged. Eight of 43 (19%) mixing studies of patients with prolonged PT and aPTT normalized; the aPTT normalized, but the PT remained prolonged in 17 of 43 (39%); the PT normalized, but the aPTT remained prolonged in 7 of 43 (16%); and both tests remained prolonged in 11 of 43 (26%) samples. Prolongations in the aPTT were primarily associated with low activities of CF XII, while the majority of the prolongations in PT were secondary to low activities in CF VII. Combined prolongations were secondary to deficiencies in both the intrinsic and extrinsic as well as the common pathways. An ICA >11% had 100% (95% CI, 59%-100%) sensitivity, 53% (95% CI, 35%-70%) specificity, and 77% (95% CI, 62%-92%) accuracy in predicting the presence of lupus anticoagulant in patients with prolonged aPTT. CONCLUSIONS: Normalization of the aPTT and PT in a mixing study was associated with low clotting factor activity. The ICA may be helpful in predicting the presence of a lupus anticoagulant. As anesthesiologists take ownership of the perioperative surgical home, we need to understand the clinical implications of the results of mixing studies.

CD8+ lineage dendritic cells determine adaptive immune responses to inflammasome activation upon sterile skin injury.

The molecular links between sterile inflammation and induction of adaptive immunity have not been fully identified. Here, we examine how damage-associated molecular patterns (DAMPs), as opposed to pathogen-associated molecules (PAMPs), regulate the immune response to non-self-antigens presented at the site of a physical injury. Heat applied briefly to the skin invokes sterile inflammation, characterized by local cell death and caspase-1 activation without demonstrably disrupting skin integrity. Co-delivery of ovalbumin (OVA) with heat injury induces OVA-specific CD8+ T-cell responses, and this is dependent on caspase-1 activation and MyD88 signalling. Using Id2flox/flox-CD11cCre+ mice, we demonstrate that CD8+ lineage DCs are required to induce OVA-specific CD8+ T-cell responses following heat injury. Consistent with this observation, intradermal administration of CD8+ lineage DCs but not CD11b+ lineage DCs restores priming of CD8+ T-cell responses in Casp-1-/- mice. Thus, we conclude that a sterile injury induces CD8+ T-cell immune responses to local antigen through caspase-1 activation and requires CD8+ lineage DCs, a finding of significance for immunotherapy and for the pathogenesis of autoimmunity.

A Prospective Randomized Trial of Prognostic Genicular Nerve Blocks to Determine the Predictive Value for the Outcome of Cooled Radiofrequency Ablation for Chronic Knee Pain Due to Osteoarthritis.

Background and Objectives: Genicular nerve radiofrequency ablation is an effective treatment for patients with chronic pain due to knee osteoarthritis; however, little is known about factors that predict procedure success. The current study evaluated the utility of genicular nerve blocks to predict the outcome of genicular nerve cooled radiofrequency ablation (cRFA) in patients with osteoarthritis. Methods: This randomized comparative trial included patients with chronic knee pain due to osteoarthritis. Participants were randomized to receive a genicular nerve block or no block prior to cRFA. Patients receiving a prognostic block that demonstrated ≥50% pain relief for six hours received cRFA. The primary outcome was the proportion of participants with ≥50% reduction in knee pain at six months. Results: Twenty-nine participants (36 knees) had cRFA following a prognostic block, and 25 patients (35 knees) had cRFA without a block. Seventeen participants (58.6%) in the prognostic block group and 16 (64.0%) in the no block group had ≥50% pain relief at six months (P = 0.34). A 15-point decrease in the Western Ontario and McMaster Universities Osteoarthritis Index at six months was present in 17 of 29 (55.2%) in the prognostic block group and 15 of 25 (60%) in the no block group (P = 0.36). Conclusions: This study demonstrated clinically meaningful improvements in pain and physical function up to six months following cRFA. A prognostic genicular nerve block using a local anesthetic volume of 1 mL at each injection site and a threshold of ≥ 50% pain relief for subsequent cRFA eligibility did not improve the rate of treatment success.

Single dose systemic acetaminophen to improve patient reported quality of recovery after ambulatory segmental mastectomy: A prospective, randomized, double-blinded, placebo controlled, clinical trial.

Few systemic drug interventions are efficacious to improve patient reported quality of recovery after ambulatory surgery. We aimed to evaluate whether a single dose systemic acetaminophen improve quality of recovery in female patients undergoing ambulatory breast surgery. We hypothesized that patients receiving a single dose systemic acetaminophen at the end of the surgical procedure would have a better global quality of postsurgical recovery compared to the ones receiving saline. The study was a prospective randomized double blinded, placebo controlled, clinical trial. Healthy female subjects were randomized to receive 1 g single dose systemic acetaminophen at the end of the surgery or the same volume of saline. The primary outcome was the Quality of Recovery 40 (QOR-40) questionnaire at 24 hours after surgery. Other data collected included opioid consumption and pain scores. Data were analyzed using group t tests and the Wilcoxon exact test. The association between opioid consumption and quality of recovery was evaluated using Spearman rho. P < .05 was used to reject the null hypothesis for the primary outcome. Seventy subjects were randomized and sixty-five completed the study. Patients' baseline characteristics and surgical factors were similar between the study groups. There was a clinically significant difference in the global QoR-40 scores between the acetaminophen and the saline groups, median (IQR) of 189 (183 to 194) and 183 (175 to 190), respectively, P = .01. In addition, there was an inverse relationship (Spearman's rho= -0.33) between oral opioid consumption at home (oral morphine equivalents) and 24 hour postoperative quality of recovery, P = .007. A single dose of systemic acetaminophen improves patient reported quality of recovery after ambulatory breast surgery. The use of systemic acetaminophen is an efficacious strategy to improve patient perceived quality of postsurgical recovery and analgesic outcomes after hospital discharge for ambulatory breast surgery.

The impact of health literacy on shared decision making before elective surgery: a propensity matched case control analysis.

BACKGROUND: Poor health literacy affects over 90 million Americans. The primary aim of the study was to evaluate a possible association between health literacy and decision conflict in surgical patients. METHODS: Patients undergoing a diverse number of elective surgeries were enrolled in the study. Health literacy was measured using the Newest Vital Sign instrument and decision conflict using the low literacy version of the Decision Conflict Scale. RESULTS: 200 patients undergoing elective surgeries were included in the study. Patients who had greater health literacy scores had lower decision conflict scores, Spearman's rho = - 0.43, P < 0.001. Following propensity-score matching to account for potential covariates, the median (IQR) decision conflict score was 20 (0 to 40) for patients with poor health literacy compared to 0 (0 to 5) for patients with adequate literacy, P < 0.001. CONCLUSIONS: Poor health literacy is associated with greater decision conflict in patients undergoing elective surgical procedures. Strategies should be implemented to minimize decision conflict in poor health literacy patients undergoing elective surgical procedures.

The Effect of Intraoperative Systemic Lidocaine on Postoperative Persistent Pain Using Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials Criteria Assessment Following Breast Cancer Surgery: A Randomized, Double-Blind, Placebo-Controlled Trial.

OBJECTIVE: To compare the incidence in postsurgical persistent pain following breast cancer surgery in women receiving intravenous lidocaine compared to saline using validated pain instruments in accordance with the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) recommendations. METHODS: The study was a randomized, double-blinded, placebo-controlled, clinical trial. Subjects were randomized into Group 1 (1.5 mg/kg bolus of intravenous lidocaine followed by a 2 mg/kg/hour infusion) or Group 2 (normal saline at the same bolus and infusion rate). Patients were evaluated at 3 and 6 months for the presence of chronic persistent postsurgical pain. RESULTS: One hundred forty-eight patients were included in the study analysis. There were no differences in quality of recovery, pain burden, or opioid consumption between groups at 24 hours. Pain (yes/no) at 6 months attributed to surgery was reported in 29% of Group 2 vs. 13% of Group 1 patients (P = 0.04); however, only 3 subjects (5%) in Group 1 and 2 subjects (3%) in Group 2 met IMMPACT criteria for persistent postoperative pain (P = 0.99). DISCUSSION: Perioperative infusion of lidocaine has been reported to decrease the incidence of postsurgical pain at 3 and 6 months following mastectomy using dichotomous (yes/no) scoring. Although intravenous lidocaine reduced the reported incidence of pain at rest at 6 months, pain with activity, pain qualities, and the physical or emotional impact of the pain were unaffected. Future studies evaluating postsurgical persistent pain should adhere to the IMMPACT recommendations in order to more accurately describe the effect of an intervention on persistent pain.

Investigating the Effect of Substrate Materials on Wearable Immunoassay Performance.

Immunoassays are ubiquitous across research and clinical laboratories, yet little attention is paid to the effect of the substrate material on the assay performance characteristics. Given the emerging interest in wearable immunoassay formats, investigations into substrate materials that provide an optimal mix of mechanical and bioanalytical properties are paramount. In the course of our research in developing wearable immunoassays which can penetrate skin to selectively capture disease antigens from the underlying blood vessels, we recently identified significant differences in immunoassay performance between gold and polycarbonate surfaces, even with a consistent surface modification procedure. We observed significant differences in PEG density, antibody immobilization, and nonspecific adsorption between the two substrates. Despite a higher PEG density formed on gold-coated surfaces than on amine-functionalized polycarbonate, the latter revealed a higher immobilized capture antibody density and lower nonspecific adsorption, leading to improved signal-to-noise ratios and assay sensitivities. The major conclusion from this study is that in designing wearable bioassays or biosensors, the design and its effect on the antifouling polymer layer can significantly affect the assay performance in terms of analytical specificity and sensitivity.

Does Cervical Interlaminar Epidural Steroid Injection with Low-Dose Lidocaine Cause Objective Upper Extremity Weakness? A Preliminary Study.

OBJECTIVE: Low-dose local anesthetic is often used in cervical interlaminar epidural steroid injections (CIESI), yet its effect on upper extremity strength has not been studied. The presence of consequent weakness has potential implications for postprocedure safety. This study aimed to determine whether low-dose lidocaine in a C7-T1 CIESI causes objective weakness. DESIGN: Prospective case series. SETTING: Academic pain center. SUBJECTS: Adults, cervical radicular pain. METHODS: Participants underwent CIESI with 1 mL of 1% lidocaine (3 mL total injectate). Elbow flexion (EF), wrist extension (WE), elbow extension (EE), and handgrip strength were measured by dynamometry at baseline, 15 minutes, and 30 minutes postinjection. Changes in strength from baseline and the proportion of participants with a minimum perceptible change in EF, WE, EE, and handgrip strength (≥20%) and 95% confidence intervals (CIs) were calculated. RESULTS: Twenty-seven participants were included. At 15 and 30 minutes postinjection, there was no within-participant difference in EF, WE, EE, and handgrip strength from baseline overall. Nonetheless, five (19%, 95% CI = 4-33) of the participants demonstrated a 20% or greater strength decrease in at least one myotomal distribution. A 20% or greater decrease in strength was present in left EF 4% (95% CI = 0-11%), right EF 7% (95% CI = 0-17%), left WE 4% (95% CI = 0-11%), and right WE 7% (95% CI = 0-17%). CONCLUSIONS: The present data suggest that CIESI with an injectate volume of 3 mL that includes 1 mL of 1% lidocaine may result in objective upper extremity weakness that is above the minimum threshold of perception in a subset of patients.

The relationship between the Bispectral Index (BIS) and the Observer Alertness of Sedation Scale (OASS) scores during propofol sedation with and without ketamine: a randomized, double blinded, placebo controlled clinical trial.

Prior studies have examined the static effect of intravenous ketamine on the BIS Index for sedation but it remains unknown if the BIS Index is a reliable method to track sedation levels in the presence of ketamine. The major objective of the current investigation was to compare the BIS Vista Index ability to track varying depths of sedation as determined by OASS scores in a standardized anesthetic regimen with and without ketamine. The study was a randomized, double blinded clinical trial. Patients undergoing breast surgery under sedation with propofol were randomized to receive ketamine (1.5 µg kg min(-1)) or saline. Infusion data was used to estimate propofol plasma concentrations (Cp). The main outcome of interest was the correlation between the BIS Vista Index with the OASS score. Twenty subjects were recruited and fifteen completed the study. Four hundred fifty-five paired data points were included in the analysis. Model performance (Nagelkerke R(2)) of the multinomial logistic regression model was 0.57 with the c-statistic of 0.87 (95 % CI 0.82-0.91). Compared to awake the odds ratio for BIS values predicting moderate sedation in the saline/propofol group 1.19 (95 % CI 1.12-1.25) but only 1.06 (95 % CI 1.02-1.1) in the ketamine/propofol group (P = 0.001). There was no difference in the odds for BIS values to predict deep sedation between groups (P = 0.14). The BIS monitor can be used to monitor sedation level even when ketamine is used with propofol as part of the sedation regimen. However, ketamine reduces the value of the BIS in predicting moderate sedation levels.