Qualitative Comparison of Cryostat- versus Snap-Frozen Neurosurgical Intraoperative Consultations.

Background. Frozen sections (FS) are common in neurosurgery to address varied clinical concerns. Artifacts in central nervous system (CNS) FS can be severe and affect or hinder interpretation. We performed a case-control study using a semiquantitative scale: the Histologic Preservation Score (HPS), and a quantitative scale: the Ice Crystal Vacuolization Score (ICVS), to compare the histologic quality yielded by snap- versus cryostat freezing techniques. Material and Methods. All specimens were sectioned in 2 halves, one half was used for FS and the other for permanent evaluation. HPS assigns a distortion score to the FS sample using the non-frozen half as the comparator: 1 = minimal, 2 = slight, 3 = moderate, 4 & 5 = severe. The ICVS is the average size in µm of the 5 largest vacuoles/0.05 mm2, evaluated on digitized slides. Results. 86 CNS-FS were collected: 22 snap- and 64 cryostat-FS. Significant differences in HPS: 2.28 versus 2.84 (p <0.05) and ICVS 7.47 versus 14.56 (p < 0.001) were obtained for snap- versus cryostat-FS, respectively. HPS and ICVS showed a strong correlation: R2 = 0.63, p < 0.0001. Histologic distortion was worse for neuroglial than mesenchymal tissue by both methods; however, a significant difference was only observed in cryostat-FS: HPS: 3.23 versus 2.33, p < 0.001; ICVS: 16.86 µm versus 10.26 µm, p < 0.001. Conclusion. Snap-FS yields better histologic quality than cryostat-FS for CNS-FS, and the difference is more pronounced in neuroglial samples. HPS and ICVS correlate strongly, indicating that the histologic quality is inversely proportional to water-crystallization. These results may apply to other areas of surgical pathology.

Design and development of a self-assembling protein nanoparticle displaying PfHAP2 antigenic determinants recognized by natural acquired antibodies.

BACKGROUNDS: In order to move towards the elimination and eradication of malaria in the world, the development of vaccines is inevitable. Many modern vaccines are based on recombinant technology; however, they may not provide a fully protective, long-lasting immune response. One of the strategies to improve recombinant vaccines is designing the nanovaccines such as self-assembling protein nanoparticles (SAPNs). Hence, the presentation of epitopes in a repeat array and correct conformation should be considered. P. falciparum generative cell-specific 1 (PfGCS1) is a main transmission-blocking vaccine candidate with two highly conserved fragments, HAP2-GCS1 and cd loop, inducing partial malaria transmission inhibitory antibodies. Therefore, to design an effective malaria vaccine, we used cd loop and HAP2-GCS1 fragments at the amino and carboxy terminuses of the SAPN-forming amino acid sequence, respectively. METHODOLOGY/PRINCIPAL FINDINGS: The SAPN monomer (PfGCS1-SAPN) sequence was designed, and the three-dimensional (3D) structure was predicted. The result of this prediction ensured the presence of antigens on the SAPN surface. Then the accuracy of the predicted 3D structure and its stability were confirmed by 100 ns molecular dynamics (MD) simulation. The designed SAPN substructure sequence was synthesized, cloned, and expressed in Escherichia coli. With a gradual decrease in urea concentration in dialysis solutions, the purified proteins progressed to the final desired structure of the SAPN, which then was confirmed by Dynamic Light Scattering (DLS) and Field Emission Scanning Electron Microscopy (FESEM) tests. According to the Enzyme-Linked Immunosorbent Assay (ELISA), antigenic determinants were presented on the SAPN surface and interacted with antibodies in the serum of malaria patients. CONCLUSIONS/SIGNIFICANCE: Our results show that the SAPN formed by PfGCS1-SAPN has produced the correct shape and size, and the antigenic determinants are presented on the surface of the SAPN, which indicates that the designed SAPN has great potential to be used in the future as a malaria vaccine.

Evaluation of Differentiation Quality of Several Differentiation Inducers of Bone Marrow-derived Mesenchymal Stem Cells to Nerve Cells by Assessing Expression of Beta-tubulin 3 Marker: A Systematic Review.

Neurological diseases have different etiological causes. Contemporary, developing an effective treatment for these diseases is an ongoing challenge. Cell therapy is recognized as one of the promising solutions for the treatment of these diseases. Amongst various types of stem cells, bone marrow-derived mesenchymal stem cells (BM-MSC) are known to be the most widely used stem cells. These cells are endowed with appealing properties such as the ability to differentiate into other cell types, including the muscle, liver, glial, and nerve cells. In this review study, we have systematically evaluated the ability of a variety of chemical compounds used in the last ten years to differentiate BM-MSCs into neurons by examining the expression level of beta-tubulin 3 protein. The present study is a systematic search performed at three separate databases, including PubMed, ScienceDirect, and Embase from August 2009 to August 2019. The search results in the three mentioned databases were 323 articles and finally, 8 articles were selected and carefully examined considering the inclusion and exclusion criteria. The results showed that different chemical compounds such as ROCK inhibitors, sex steroid hormones, bFGF, NGF, Noggin, 4 OHT, TSA, VPA, Antidepressants, Neurosteroids (Dex and E2), and DHA are involved in different signaling pathways, such as ERK, AKT, BMP, DHA / GPR40, Rho-dependent phosphorylation, and histone deacetylase inhibitors. Further investigation of these signaling pathways may open the way for better differentiation of BM-MSCs into neurons.

Comparison of lidocaine-dexmedetomidine and lidocaine-saline on the characteristics of the modified forearm bier block: A clinical trial.

Background and Aims: Forearm Modified Bier Block (FMBB) reduces local anesthetic systemic toxicity risks compared to the traditional method. This study was designed and implemented to compare the effects of lidocaine-dexmedetomidine (LD) and lidocaine-saline (LS) on the characteristics of the MFBB in distal forearm and hand surgery. Material and Methods: In this randomized double-blind trial, which was conducted after obtaining institutional ethical committee approval, 60 patients were enrolled and randomly divided into two groups. In both groups, the analgesic base of the block was 20 mL lidocaine 0.5% that was supplemented by 1 µg/kg dexmedetomidine in the LD group or 1 mL of 0.9% saline in the LS group. Patients were evaluated for the onset and duration of sensory block, time of the first request for postoperative analgesic, and analgesic request frequency during the first 24 h after surgery. Results: Sensory block onset in the LD group (7.1 ± 1.4 min) compared to the LS group (8.4 ± 1.4) was faster (P = 0.008). Duration of the sensory block in LD group (49.7 ± 7.2 min) was longer than LS group (33.3 ± 2.6) (P < 0.001). Compared to LS group, time of the first request for postoperative analgesic in LD group was later (P = 0.6), and had lesser analgesic requests during the first 24 h after surgery (P < 0.001). Conclusion: Based on our study's finding, adding dexmedetomidine to lidocaine in the MFBB increases the duration of sensory block.

Postpartum Headache due to Cerebellar Infarct Initially Misdiagnosed as Postdural Puncture Headache: A Case Report.

We present the case of a 39-year-old woman with postpartum cerebellar infarction (CI) following spinal anesthesia for cesarean delivery. The patient experienced mild headache after postoperative day 1 and returned on postoperative day 6 with a severe headache. For the subsequent 3 days, she underwent conservative treatment for presumed postdural puncture headache (PDPH) before neurologic decline and diagnosis of CI on postoperative day 9. She subsequently underwent craniotomy and debridement of necrotic tissues. Prolonged or position-independent postpartum headache should prompt broadening of the differential diagnosis beyond PDPH to include other more rare but serious causes of postpartum headache.

Intraoperative Provocative Testing in Patients with Obstructive Hypertrophic Cardiomyopathy Undergoing Septal Myectomy.

BACKGROUND: Resolution of left ventricular outflow tract (LVOT) obstruction predicts symptom relief postmyectomy. Intraoperative measurement of LVOT gradients thus is essential for surgical guidance. We hypothesized that (1) hypertrophic cardiomyopathy patients have lower LVOT gradients when measured intraoperatively with transesophageal echocardiography (TEE) compared with preoperative measurements with transthoracic echocardiography (TTE) and that (2) intraoperative provocative testing can help evaluate the adequacy of surgical resection. METHODS: We compared resting LVOT gradients on preoperative TTE to intraoperative TEE. We also compared intraoperative resting and provoked gradients pre- and postresection. Either isoproterenol 10 µg/kg/min or dobutamine 20 µg/kg/min was used. Patients with provoked LVOT gradients >30 mm Hg were considered for further resection based on LVOT/mitral valve morphology and clinical comorbidities. RESULTS: Of 315 patients identified, 293 patients were included in the analysis. There was a statistically significant difference between preoperative TTE and intraoperative TEE resting LVOT gradients (60.9 ± 39.4 mm Hg vs 42.0 ± 30.5 mm Hg, P < .0001). Out of 197 patients who had significant resting obstruction preoperatively, 82 (41.6%) demonstrated mild or no dynamic obstruction under general anesthesia. Provocative testing with both isoproterenol and dobutamine increased peak gradients (116.8 ± 33 mm Hg isoproterenol vs 107.5 ± 33 mm Hg dobutamine, P = .03). Post-cardiopulmonary bypass, seven patients (2.3%) had LVOT gradients > 30 mm Hg at rest, while 63 patients (21.5%) had residual gradients >30 mm Hg only with provocation. Elevated gradients, persistent systolic anterior motion of the mitral valve with near contact, and/or significant mitral regurgitation with provocative testing resulted in return to cardiopulmonary bypass in 41 patients (14%). CONCLUSIONS: Resting intraoperative TEE LVOT gradients are significantly lower than preoperative TTE gradients, with systolic anterior motion of the MV and outflow obstruction often not visualized after inducing general anesthesia. Intraoperative pharmacologic provocation can identify patients who may benefit from further surgical intervention, facilitating procedural success.

Chronic postthoracotomy pain in transapical transcatheter aortic valve replacement.

Objective: Chronic postthoracotomy pain (CPTP) is a persistent, occasionally debilitating pain lasting >2 months following thoracic surgery. This study investigates for the first time the prevalence and clinical impact of CPTP in patients who have undergone a transapical transcatheter aortic valve replacement (TA-TAVR). Design: This was a single-institution, prospective observational survey and a retrospective chart review. Setting: The study was conducted in the University Hospital. Participants: Patients. Materials and Methods: A survey of 131 participants with either a previous TA TAVR or transfemoral (TF) TAVR procedure was completed. A telephone interview was conducted at least 2 months following TAVR; participants were asked to describe their pain using the Short-Form McGill Pain Questionnaire. Measurements and Main Results: Odds ratio (OR) was calculated using the proportions of questionnaire responders reporting "sensory" descriptors in the TA-TAVR versus the TF-TAVR groups. Results were then compared to individual Kansas City Cardiomyopathy Questionnaire (KCCQ12) scores and 5-min walk test (5MWT) distances. A total of 119 participants were reviewed (63 TF, 56 TA). Among TA-TAVR questionnaire responders (n = 16), CPTP was found in 64.3% of participants for an average duration of 20.5-month postprocedure (OR = 10, [confidence interval (CI) 95% 1.91-52.5];P = 0.003). TA-TAVR patients identified with CPTP had significant reductions in 5MWT distances (-2.22 m vs. 0.92 m [P = 0.04]) as well as trend toward significance in negative change of KCCQ12 scores OR = 18.82 (CI 95% 0.85-414.99;P = 0.06) compared to those without CPTP. Conclusions: CPTP occurs in patients undergoing TA-TAVR and is possibly associated with a decline quality of life and overall function.

Intraoperative Hemodynamic and Echocardiographic Measurements Associated With Severe Right Ventricular Failure After Left Ventricular Assist Device Implantation.

BACKGROUND: Severe right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation increases morbidity and mortality. We investigated the association between intraoperative right heart hemodynamic data, echocardiographic parameters, and severe versus nonsevere RVF. METHODS: A review of LVAD patients between March 2013 and March 2016 was performed. Severe RVF was defined by the need for a right ventricular mechanical support device, inotropic, and/or inhaled pulmonary vasodilator requirements for >14 days. From a chart review, the right ventricular failure risk score was calculated and right heart hemodynamic data were collected. Pulmonary artery pulsatility index (PAPi) [(pulmonary artery systolic pressure - pulmonary artery diastolic pressure)/central venous pressure (CVP)] was calculated for 2 periods: (1) 30 minutes before cardiopulmonary bypass (CPB) and (2) after chest closure. Echocardiographic data were recorded pre-CPB and post-CPB by a blinded reviewer. Univariate logistic regression models were used to examine the performance of hemodynamic and echocardiographic metrics. RESULTS: A total of 110 LVAD patients were identified. Twenty-five did not meet criteria for RVF. Of the remaining 85 patients, 28 (33%) met criteria for severe RVF. Hemodynamic factors associated with severe RVF included: higher CVP values after chest closure (18 ± 9 vs 13 ± 5 mm Hg; P = .0008) in addition to lower PAPi pre-CPB (1.2 ± 0.6 vs 1.7 ± 1.0; P = .04) and after chest closure (0.9 ± 0.5 vs 1.5 ± 0.8; P = .0008). Post-CPB echocardiographic findings associated with severe RVF included: larger right atrial diameter major axis (5.4 ± 0.9 vs 4.9 ± 1.0 cm; P = .03), larger right ventricle end-systolic area (22.6 ± 8.4 vs 18.5 ± 7.9 cm; P = .03), lower fractional area of change (20.2 ± 10.8 vs 25.9 ± 12.6; P = .04), and lower tricuspid annular plane systolic excursion (0.9 ± 0.2 vs 1.1 ± 0.3 cm; P = .008). Right ventricular failure risk score was not a significant predictor of severe RVF. Post-chest closure CVP and post-chest closure PAPi discriminated severe from nonsevere RVF better than other variables measured, each with an area under the curve of 0.75 (95% CI, 0.64-0.86). CONCLUSIONS: Post-chest closure values of CVP and PAPi were significantly associated with severe RVF. Echocardiographic assessment of RV function post-CPB was weakly associated with severe RVF.

Minute ventilation assessment in the PACU is useful to predict postoperative respiratory depression following discharge to the floor: A prospective cohort study.

STUDY OBJECTIVE: Reliably identifying patients at risk for postoperative respiratory depression (RD) remains an unmet need. We hypothesized that defined low minute ventilation events (LMVe) near the end of the post-anesthesia care unit (PACU) stay identifies patients at RD risk on the general hospital floor (GHF). DESIGN: Prospective observational study. SETTING: Tertiary care, urban academic medical center. PACU and GHF during the first postoperative night. PATIENTS: One hundred-and-nineteen adult, ASA I - III patients undergoing elective surgery under general anesthesia completed the study. INTERVENTIONS: Data collection from a non-invasive respiratory volume monitor and the patients' medical record perioperatively through the first postoperative night. MEASUREMENTS: Minute ventilation (MV), tidal volume (TV) and respiratory rate (RR) were measured continuously in the PACU and on the GHF. MV was counted as the percent of individual predicted MV (MVPRED), and RD was defined as ≥1 LMVe/h on the GHF. Based on the number of LMVes within 30 min before PACU discharge, patients were grouped into A, 'Not-At-Risk': 0 LMVe and B, 'At-Risk': ≥1 LMVes. Unpaired t-test, Mann-Whitney U test, ANOVA, Kruskal-Wallis test, Fisher's exact test, sensitivity and specificity and ROC curve analyses were applied as appropriate. MAIN RESULTS: One hundred-and-six (89%) and 13 (11%) patients met Group A and B criteria respectively. The latter had more LMVe/h on the GHF (median 0.81 vs 0, p ≤ 0.001), and their MVPRED was significantly less. Following opioid administration, the LMVe likelihood was 43% in Group B and 5.6% in Group A. As a predictor for RD on the GHF, the number of LMVe in the last 30 min of PACU, had positive and negative predictive values of 61.5% and 90.6%, respectively. CONCLUSION: Minute ventilation assessment in the PACU as described in this study can be useful to identify patients at risk for postoperative respiratory depression.

Intraoperative Administration of 4-Factor Prothrombin Complex Concentrate Reduces Blood Requirements in Cardiac Transplantation.

OBJECTIVE: Assessing the efficacy of intraoperative 4-factor prothrombin complex concentrate (4F-PCC) use in blood product utilization, time to chest closure, intensive care unit (ICU) and hospital length of stay (LOS), thromboembolic complications, renal injury and mortality in left ventricular assist device (LVAD) patients on home anticoagulation therapy with warfarin, undergoing orthotopic heart transplantation (OHT). DESIGN: Retrospective analysis of OHT patients at Tufts Medical Center from May 2013 to October 2016. SETTING: Single-institution, university hospital setting. PARTICIPANTS: Patients with preexisting LVADs who received orthotopic heart transplants (n = 74; 32 patients 4F-PCC, 42 patients no 4F-PCC). INTERVENTIONS: Warfarin reversal using 4F-PCC in patients with LVADs undergoing orthotopic heart transplantation with the 4F-PCC dosing partitioned such that one-third was given pre-CPB and two-thirds were given post-CPB. MEASUREMENTS AND MAIN RESULTS: The 4F-PCC group required less plasma (6 [IQR 4] v 1.31 [IQR 2] U, p < 0.001), cryoprecipitate (10 [IQR 10] v 7.50 [IQR 5] U, p < 0.001), and packed red blood cells (5 [IQR 4] v 2 [IQR 1.5] U, p < 0.001) and had a shorter time to chest closure (618.8 ± 111.4 v 547.9 ± 110.1 minutes, p = 0.008). There was no difference in platelet transfusion (2 [IQR 1] v 2 [IQR 1] U, p = 0.16), ICU or hospital LOS, acute kidney injury, or mortality. No thrombotic complications occurred. CONCLUSIONS: Replacing plasma with 4F-PCC to reverse preoperative warfarin anticoagulation during OHT was associated with a shorter time to chest closure and less blood product utilization, without an increase in acute kidney injury, thromboembolic complications, or death.

Comparison of forced-air and water-circulating warming for prevention of hypothermia during transcatheter aortic valve replacement.

INTRODUCTION: Transcatheter Aortic Valve Replacement (TAVR) procedures at our institution were complicated by perioperative hypothermia despite use of the standard of care forced-air convective warming device (the BairHugger, Augustine Medical Inc, Eden Prairie, MN, USA). To remedy this problem, we initiated a quality improvement process that investigated the use of a conductive warm water-circulating device (the Allon ThermoWrap, Menen Medical Corporation, Trevose, PA, USA), and hypothesized that it would decrease the incidence of perioperative hypothermia. METHODS: We compared two different intraoperative warming devices using a historic control. We retrospectively reviewed intraoperative records of 80 TAVRs between 6/2013 and 6/2015, 46 and 34 of which were done with the forced-air and water-circulating devices, respectively. Continuous temperature data obtained from pulmonary artery catheter, temperature upon arrival to cardiothoracic ICU (CTU), age, BSA, height, and BMI were compared. RESULTS: Patients warmed with both devices were similar in terms of demographic characteristics. First recorded intraoperative temperature (mean 36.26 ± SD 0.61 vs. 35.95 ± 0.46°C, p = 0.02), lowest intraoperative temperature (36.01 ± 0.58 vs. 34.89 ± 0.76°C, p<0.001), temperature at the end of the procedure (36.47 ± 0.51 vs. 35.17 ± 0.75°C, p<0.001), and temperature upon arrival to the CTU (36.35 ± 0.44 vs. 35.07 ± 0.78°C, p<0.001) were significantly higher in the water-circulating group as compared to the forced-air group. CONCLUSION: A quality improvement process led to selection of a new warming device that virtually eliminated perioperative hypothermia at our institution. Patients warmed with the new device were significantly less likely to experience intraoperative hypothermia and were significantly more likely to be normothermic upon arrival to the CTU.

The risk of wound infection after simple hand laceration.

BACKGROUND: This prospective observational study aimed to determine the infection rate of simple hand laceration (SHL), and to compare infection rates between patients who were prescribed antibiotics and those who were not. METHODS: The study was performed at two urban hospitals enrolling 125 emergency department (ED) patients with SHL. Exclusion criteria included patients with lacerations for more than 12 hours, immunocompromized patients, patients given antibiotics, and patients with gross contamination, bites or crush injuries. Wound infection was defined as clinical infection at a follow-up visit (10-14 days) or wound was treated with antibiotics. Patient satisfaction was also measured using a visual analogue scale 1-10, asking the patients about wound appearance. Demographic data and wound characteristics were compared between the infected and non-infected wounds. The infection rates were also compared between patients who received prophylactic antibiotics and those who did not. The results were presented with medians and quartiles or percentages with 95% confidence intervals (CI). RESULTS: In the 125 patients SHL [median age: 28 (18, 43); range: 1-102 years old; 36% female], 44 (35%, 95% CI: 27%-44%) were given antibiotics in the ED. Wound infection was reported in 6 patients (4.8%, 95% CI: 2%-10%). Age, gender, history of diabetes and wound closure were not associated with wound infection (P>0.05). The infection rate was not significantly different between patients with or without antibiotic prophylaxis [7% (3/44), 95% CI: 2%-10% vs. 4% (3/81), 95% CI: 1%-11%, P=0.66]. Patient's satisfaction with appearance of infected and non-infected wounds were significantly different [7.5 (6, 8) vs. 9 (8, 10), P=0.01]. CONCLUSION: Approximately 5% of simple hand lacerations become infected. Age, gender, diabetes, prophylactic antibiotics and closure technique do not affect the risk of infection.

The risk of wound infection after simple hand laceration / 世界急诊医学杂志（英文）

@#BACKGROUND: This prospective observational study aimed to determine the infection rate of simple hand laceration (SHL), and to compare infection rates between patients who were prescribed antibiotics and those who were not. METHODS: The study was performed at two urban hospitals enrolling 125 emergency department (ED) patients with SHL. Exclusion criteria included patients with lacerations for more than 12 hours, immunocompromized patients, patients given antibiotics, and patients with gross contamination, bites or crush injuries. Wound infection was defined as clinical infection at a follow-up visit (10–14 days) or wound was treated with antibiotics. Patient satisfaction was also measured using a visual analogue scale 1–10, asking the patients about wound appearance. Demographic data and wound characteristics were compared between the infected and non-infected wounds. The infection rates were also compared between patients who received prophylactic antibiotics and those who did not. The results were presented with medians and quartiles or percentages with 95％ confidence intervals (CI). RESULTS: In the 125 patients with SHL [median age: 28 (18, 43); range: 1–102 years old; 36％female], 44 (35％, 95％ CI: 27％–44％) were given antibiotics in the ED. Wound infection was reported in 6 patients (4.8％, 95％ CI: 2％–10％). Age, gender, history of diabetes and wound closure were not associated with wound infection (P>0.05). The infection rate was not significantly different between patients with or without antibiotic prophylaxis [7％ (3/44), 95％ CI: 2％–10％ vs. 4％ (3/81), 95％ CI:1％–11％, P=0.66]. Patient's satisfaction with appearance of infected and non-infected wounds were significantly different [7.5 (6, 8) vs. 9 (8, 10), P=0.01]. CONCLUSION: Approximately 5％ of simple hand lacerations become infected. Age, gender, diabetes, prophylactic antibiotics and closure technique do not affect the risk of infection.