Do Not Resuscitate status as an independent risk factor for patients undergoing surgery for hip fracture

AIM To determine morbidity and mortality in this specific patient group and also to assess for any independent associations between Do Not Resuscitate(DNR) status and increased post-operative morbidity and mortality.METHODS We conducted a propensity score matched retrospective analysis using de-identified data from the American College of Surgeons' National Surgical Quality Improvement Project(ACS NSQIP) for all patients undergoing hip fracture surgery over a 7 year period in hospitals across the United States enrolled in ACS NSQIP with and without Do Not Resuscitate Status. We measured patient demographics including DNR status, co-morbidities, frailty and functional baseline, surgical and anaestheticprocedure data, post-operative morbidity/complications, length of stay, discharge destination and mortality.RESULTS Of 9218 patients meeting the inclusion criteria, 13.6% had a DNR status, 86.4% did not. Mortality was higher in the DNR status compared to the non-DNR group, at 15.3% vs 8.1% and propensity score matched multivariable analysis demonstrated that DNR status was independently associated with mortality(OR = 2.04, 95%CI: 1.46-2.86, P < 0.001). Additionally, analysis of the propensity score matched cohort demonstrated that DNR status was associated with a significant, but very small increased likelihood of post-operative complications(0.53 vs 0.43 complications per episode; OR = 1.21; 95%CI: 1.04-1.41, P = 0.004). Cardiopulmonary resuscitation and unplanned reintubation were significantly less likely in patients with DNR status.CONCLUSION Whilst DNR status patients had higher rates of postoperative complications and mortality, DNR status itself was not otherwise associated with increased morbidity. DNR status appears to increase 30-d mortality via ceilings of care in keeping with a DNR status, including withholding reintubation and cardiopulmonary resuscitation.

Therapeutic benefits of mild hypothermia in patients successfully resuscitated from cardiac arrest:A meta-analysis

BACKGROUND:Good neurological outcome after cardiac arrest(CA) is hard to achieve for clinicians.Experimental and clinical evidence suggests that therapeutic mild hypothermia is beneficial.This study aimed to assess the effectiveness and safety of therapeutic mild hypothermia in patients successfully resuscitated from CA using a meta-analysis.METHODS:We searched the MEDLINE(1966 to April 2012),OVID(1980 to April 2012),EMBASE(1980 to April 2012),Chinese bio-medical literature & retrieval system(CBM)(1978 to April 2012),Chinese medical current contents(CMCC)(1995 to April 2012),and Chinese medical academic conference(CMAC)(1994 to April 2012).Studies were included if 1) the study design was a randomized controlled trial(RCT);2) the study population included patients successfully resuscitated from CA,and received either standard post-resuscitation care with normothermia or mild hypothermia;3) the study provided data on good neurologic outcome and survival to hospital discharge.Relative risk(RR) and 95%confidence interval(CI) were used to pool the effect.RESULTS:The study included four RCTs with a total of 417 patients successfully resuscitated from CA.Compared to standard post-resuscitation care with normothermia,patients in the hypothermia group were more likely to have good neurologic outcome(RR=1.43,95%CI 1.14-1.80,P=0.002) and were more likely to survive to hospital discharge(RR=1.32,95%CI 1.08-1.63,P=0.008).There was no significant difference in adverse events between the normothermia and hypothermia groups(P>0.05),nor heterogeneity and publication bias.CONCLUSION:Therapeutic mild hypothermia improves neurologic outcome and survival in patients successfully resuscitated from CA.

A novel predictor of unsustained return of spontaneous circulation in cardiac arrest patients through a combination of capnography and pulse oximetry: a multicenter observational study

BACKGROUND:Unsustained return of spontaneous circulation(ROSC)is a critical barrier to survival in cardiac arrest patients.This study examined whether end-tidal carbon dioxide(ETCO_(2))and pulse oximetry photoplethysmogram(POP)parameters can be used to identify unsustained ROSC.METHODS:We conducted a multicenter observational prospective cohort study of consecutive patients with cardiac arrest from 2013 to 2014.Patients’general information,ETCO_(2),and POP parameters were collected and statistically analyzed.RESULTS:The included 105 ROSC episodes(from 80 cardiac arrest patients)comprised 51 sustained ROSC episodes and 54 unsustained ROSC episodes.The 24-hour survival rate was significantly higher in the sustained ROSC group than in the unsustained ROSC group(29.2%vs.9.4%,P<0.05).The logistic regression analysis showed that the difference between after and before ROSC in ETCO_(2)(ΔETCO_(2))and the difference between after and before ROCS in area under the curve of POP(ΔAUCp)were independently associated with sustained ROSC(odds ratio[OR]=0.931,95%confi dence interval[95%CI]0.881-0.984,P=0.011 and OR=0.998,95%CI 0.997-0.999,P<0.001).The area under the receiver operating characteristic curve ofΔETCO_(2),ΔAUCp,and the combination of both to predict unsustained ROSC were 0.752(95%CI 0.660-0.844),0.883(95%CI 0.818-0.948),and 0.902(95%CI 0.842-0.962),respectively.CONCLUSION:Patients with unsustained ROSC have a poor prognosis.The combination ofΔETCO_(2) andΔAUCp showed signifi cant predictive value for unsustained ROSC.

Successful rescue of disseminated Nocardia infection with multiple abscesses in a patient with membranous nephropathy after cardiopulmonary resuscitation:A three-year follow-up

Nocardiosis manifests as an opportunistic infection,primarily affecting individuals who are immunocompromised and susceptible to the infection.We present a case study of one patient with nephrotic syndrome and membranous nephropathy,who underwent treatment with prednisone and cyclosporine in 2016.In early 2017,the patient was diagnosed with a"fungal infection"and discontinued the use of cyclosporine.After one month of anti-infection therapy,a cranial magnetic resonance imaging scan showed multiple abscesses in the right temporal region.The diagnosis of nocardiosis was confirmed based on the presence of metastatic abscess masses,multiple lung and brain lesions,and a positive culture of Nocardia in the drainage.We changed the anti-infection therapy to a combination of trimethoprim-sulfamethoxazole(TMP-SMX),minocycline,and voriconazole.However,the patient experienced a sudden cardiac arrest and subsequently recovered after cardiopulmonary resuscitation.During the five-month follow-up period following the discharge,the patient displayed an enhanced nutritional status and stable renal function.The focal infection ultimately resolved during the subsequent three years.Neuro-infection caused by Nocardia should be considered in immunocompromised patients,and TMP-SMX is the preferred initial therapy;however,because of the high mortality rate,a long-term combination therapy with imipenem,cefotaxime,amikacin,and TMP-SMX is suggested.

Recovering from prolonged cardiac arrest induced by electric shock:A case report

BACKGROUND Cardiac arrest(CA)induced by electric shock is a rare occurrence,particularly in cases of prolonged CA.Currently,there is limited literature on similar incidents,and we present a relevant case report.CASE SUMMARY A 27-year-old Asian male man,experiencing respiratory CA due to electric shock,was successfully restored to sinus rhythm after 50 min of cardiopulmonary resuscitation and 8 electrical defibrillation sessions.In the subsequent stages,the patient received multiple organ function protection measures,leading to a successful recovery and eventual discharge from the hospital.CONCLUSION Prolonging resuscitation time can enhance the chances of survival for patients,this study provide valuable insights into the management of electric shock-induced CA.

Effi cacy of partial and complete resuscitative endovascular balloon occlusion of the aorta in the hemorrhagic shock model of liver injury

BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic bleeding.However,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBOA)can alleviate ischemic burden;however,its security and eff ectiveness prior to operative hemorrhage control remains unknown.Hence,we aimed to estimate the effi cacy of pREBOA in a swine model of liver injury using an experimental sliding-chamber ballistic gun.METHODS:Twenty Landrace pigs were randomized into control(no aortic occlusion)(n=5),intervention with complete REBOA(cREBOA)(n=5),continuous pREBOA(C-pREBOA)(n=5),and sequential pREBOA(S-pREBOA)(n=5)groups.In the cREBOA and C-pREBOA groups,the balloon was inflated for 60 min.The hemodynamic and laboratory values were compared at various observation time points.Tissue samples immediately after animal euthanasia from the myocardium,liver,kidneys,and duodenum were collected for histological assessment using hematoxylin and eosin staining.RESULTS:Compared with the control group,the survival rate of the REBOA groups was prominently improved(all P<0.05).The total volume of blood loss was markedly lower in the cREBOA group(493.14±127.31 mL)compared with other groups(P<0.01).The pH was significantly lower at 180 min in the cREBOA and S-pREBOA groups(P<0.05).At 120 min,the S-pREBOA group showed higher alanine aminotransferase(P<0.05)but lower blood urea nitrogen compared with the cREBOA group(P<0.05).CONCLUSION:In this trauma model with liver injury,a 60-minute pREBOA resulted in improved survival rate and was effective in maintaining reliable aortic pressure,despite persistent hemorrhage.Extended tolerance time for aortic occlusion in Zone I for non-compressible torso hemorrhage was feasible with both continuous partial and sequential partial measures,and the significant improvement in the severity of acidosis and distal organ injury was observed in the sequential pREBOA.

Approach to traumatic cardiac arrest in the emergency department: a narrative literature review for emergency providers

BACKGROUND:Traumatic cardiac arrest(TCA)is a major contributor to mortality and morbidity in all age groups and poses a significant burden on the healthcare system.Although there have been advances in treatment modalities,survival rates for TCA patients remain low.This narrative literature review critically examines the indications and eff ectiveness of current therapeutic approaches in treating TCA.METHODS:We performed a literature search in the PubMed and Scopus databases for studies published before December 31,2022.The search was refi ned by combining search terms,examining relevant study references,and restricting publications to the English language.Following the search,943 articles were retrieved,and two independent reviewers conducted a screening process.RESULTS:A review of various studies on pre-and intra-arrest prognostic factors showed that survival rates were higher when patients had an initial shockable rhythm.There were conflicting results regarding other prognostic factors,such as witnessed arrest,bystander cardiopulmonary resuscitation(CPR),and the use of prehospital or in-hospital epinephrine.Emergency thoracotomy was found to result in more favorable outcomes in cases of penetrating trauma than in those with blunt trauma.Resuscitative endovascular balloon occlusion of the aorta(REBOA)provides an advantage to emergency thoracotomy in terms of occupational safety for the operator as an alternative in managing hemorrhagic shock.When implemented in the setting of aortic occlusion,emergency thoracotomy and REBOA resulted in comparable mortality rates.Veno-venous extracorporeal life support(V-V ECLS)and veno-arterial extracorporeal life support(V-A ECLS)are viable options for treating respiratory failure and cardiogenic shock,respectively.In the context of traumatic injuries,V-V ECLS has been associated with higher rates of survival to discharge than V-A ECLS.CONCLUSION:TCA remains a signifi cant challenge for emergency medical services due to its high morbidity and mortality rates.Pre-and intra-arrest prognostic factors can help identify patients who are likely to benefit from aggressive and resource-intensive resuscitation measures.Further research is needed to enhance guidelines for the clinical use of established and emerging therapeutic approaches that can help optimize treatment effi cacy and ameliorate survival outcomes.

Cardiac arrest, stony heart, and cardiopulmonary resuscitation: An updated revisit

The post-resuscitation period is recognized as the main predictor of cardiopul-monary resuscitation(CPR)outcomes.The first description of post-resuscitation syndrome and stony heart was published over 50 years ago.Major manifestations may include but are not limited to,persistent precipitating pathology,systemic ischemia/reperfusion response,post-cardiac arrest brain injury,and finally,post-cardiac arrest myocardial dysfunction(PAMD)after successful resuscitation.Why do some patients initially survive successful resuscitation,and others do not?Also,why does the myocardium response vary after resuscitation?These ques-tions have kept scientists busy for several decades since the first successful resuscitation was described.By modifying the conventional modalities of resu-scitation together with new promising agents,rescuers will be able to salvage the jeopardized post-resuscitation myocardium and prevent its progression to a dismal,stony heart.Community awareness and staff education are crucial for shortening the resuscitation time and improving short-and long-term outcomes.Awareness of these components before and early after the restoration of circulation will enhance the resuscitation outcomes.This review extensively addresses the underlying pathophysiology,management,and outcomes of post-resuscitation syndrome.The pattern,management,and outcome of PAMD and post-cardiac arrest shock are different based on many factors,including in-hospital cardiac arrest vs out-of-hospital cardiac arrest(OHCA),witnessed vs unwitnessed cardiac arrest,the underlying cause of arrest,the duration,and protocol used for CPR.Although restoring spontaneous circulation is a vital sign,it should not be the end of the game or lone primary outcome;it calls for better understanding and aggressive multi-disciplinary interventions and care.The development of stony heart post-CPR and OHCA remain the main challenges in emergency and critical care medicine.

Correction:Establishment of a prediction model for prehospital return of spontaneous circulation in out-of-hospital patients with cardiac arrest

This is an erratum to an already published paper named“Establishment of a prediction model for prehospital return of spontaneous circulation in out-ofhospital patients with cardiac arrest”.We found errors in the affiliated institution of the authors.We apologize for our unintentional mistake.Please note,these changes do not affect our results.

A Case Report: Emergency Management of a Pregnant Trauma Patient—An Anesthesiologist’s Perspective and Role

Trauma is the leading cause of death for all women of childbearing age. Motor vehicle accidents account for almost two-thirds of all maternal non-obstetric, trauma-related deaths, while falls and domestic violence comprise a large percentage of the rest. The leading causes of obstetric trauma are motor vehicle accidents, falls, assaults, and gunshots, and ensuing injuries are classified as blunt abdominal trauma, pelvic fractures, or penetrating trauma . The causes are different with different life styles and different socio-economic and cultural background. Pregnant trauma victims tend to be younger, less severely injured, and more likely African American or of Hispanic descent compared with nonpregnant victims of trauma. Drugs and alcohol are a factor in about 20 percent of maternal trauma. With pregnancy comes the challenge and responsibility of caring for two patients at once, the mother and the fetus. In general, providing optimal maternal care is the best strategy to optimize fetal survival. Decision-making including the condition of the mother, gestational age, status of the fetus, and interventions are based on these key factors. Many providers are involved in the care of the pregnant patient: at the trauma scene, in the emergency department, and in the operating room. The anesthesiologist plays a key role in the care and management of the pregnant trauma patient. All anesthesiologists have ample training in obstetric anesthesia during their residency and frequently cover obstetric units in hospitals where pregnant patients are cared for. On the other hand, most nonobstetric physicians have little obstetric exposure and may be uncomfortable caring for the pregnant patient because of unfamiliarity with the physiologic changes of pregnancy or the evaluation of fetal well-being. This is not only a source of stress for other trauma providers, but can put maternal well-being at risk. Non-obstetric physicians may hesitate to order necessary diagnostic and therapeutic interventions for fear of doing the “wrong thing,” all because the patient is pregnant. A multidisciplinary approach to the pregnant trauma patient involving trauma surgeons, obstetricians, anesthesiologists, emergency medicine, and other providers, is critical to deliver optimal care and achieve the best outcomes for both the mother and the baby. In summary, a multidisciplinary approach to provide optimal maternal care will facilitate to achieve the best outcomes for the mother and is also the best strategy for optimizing fetal survival. The following is a case report of a pregnant trauma patient who needed immediate intervention because of massive placental abruption when only a minimal workup was completed because of the urgency of the situation.

Analysis of the Application Value of Virtual Reality Combined with Flipped Classroom Teaching Mode in Cardiopulmonary Resuscitation Teaching

Objective:To analyze the value of using virtual reality combined with the flipped classroom teaching model in teaching cardiopulmonary resuscitation(CPR).Methods:Two classes of our nursing program were randomly selected for the study from September 2022 to September 2023,Class A(52 students,conventional teaching method)and Class B(52 students,virtual reality combined with flipped classroom teaching mode).The assessment scores and independent learning ability scores of the students in the two classes were compared.Results:CPR theory and operation scores,passing rate,and independent learning ability scores of Class B were higher than those of Class A(P<0.05).Conclusion:the use of virtual reality combined with the flipped classroom teaching mode in CPR teaching is conducive to the improvement of students’assessment scores and independent learning ability.

The neuro-prognostic value of the ion shift index in cardiac arrest patients following extracorporeal cardiopulmonary resuscitation

BACKGROUND:The ion shift index(ISI) as a prognostic indicator that can show the severity of hypoxic-ischemic injury.We aimed to evaluate the performance of the ISI in predicting unfavorable neurological outcomes at hospital discharge in cardiac arrest(CA) patients following extracorporeal cardiopulmonary resuscitation(ECPR) and to compare its performance to other prognostic predictors.METHODS:This was a retrospective observational study including adult CA patients treated with ECPR between January 2018 and December 2022 in a tertiary hospital.Data regarding clinical characteristics and laboratory parameters were collected from medical records.The ISI was determined based on the first available serum electrolyte levels after ECPR.The primary outcome was unfavorable neurological status at hospital discharge,defined as Cerebral Performance Categories 3–5.Comparisons of the characteristics between the two groups were made using the χ2 test for categorical variables and the t-test or non-parametric Mann-Whitney U-test for continuous variables,as appropriate.Correlation analysis was performed using Spearman’s rank correlation coeficient.A two-tailed P-value <0.05 was considered statistically significant.RESULTS:Among the 122 patients involved,46(37.7%) had out-of-hospital CA,and 88 had unfavorable neurological outcomes.The ISI was significantly higher in the unfavorable outcome group than in the favorable outcome group(3.74 [3.15–4.57] vs.2.69 [2.51–3.07],P<0.001).A higher ISI level was independently related to unfavorable outcome(odds ratio=6.529,95% confidence interval 2.239–19.044,P=0.001).An ISI level >3.12 predicted unfavorable outcomes with a sensitivity and specificity of 74.6% and 85.2%,respectively(P<0.001).The prognostic performance of ISI(area under the curve [AUC]=0.887) was similar to that of other predictors,such as gray-to-white matter ratio(AUC=0.850,P=0.433) and neuronspecific enolase(AUC=0.925,P=0.394).CONCLUSION:ISI may be used as a prognostic biomarker to predict neurological outcomes in CA patients following ECPR.

Cardiac arrest and cardiopulmonary resuscitation in“hostile”environments:Using automated compression devices to minimize the rescuers’danger

Mechanical automated compression devices are being used in cardiopulmonary resuscitation instead of manual,“hands-on”,rescuer-delivered chest compressions.The-theoretical-advantages include high-quality non-stop compressions,thus freeing the rescuer performing the compressions and additionally the ability of the rescuer to stand reasonably away from a potentially“hazardous”victim,or from hazardous and/or difficult resuscitation conditions.Such circumstances involve cardiopulmonary resuscitation(CPR)in the Cardiac Catheterization Laboratory,especially directly under the fluoroscopy panel,where radiation is well known to cause detrimental effects to the rescuer,and CPR during/after land or air transportation of cardiac arrest victims.Lastly,CPR in a coronavirus disease 2019 patient/ward,where the danger of contamination and further serious illness of the health provider is very existent.The scope of this review is to review and present literature and current guidelines regarding the use of mechanical compressions in these“hostile”and dangerous settings,while comparing them to manual compressions.

Establishment of a prediction model for prehospital return of spontaneous circulation in out-of-hospital patients with cardiac arrest

BACKGROUND Out-of-hospital cardiac arrest(OHCA)is a leading cause of death worldwide.AIM To explore factors influencing prehospital return of spontaneous circulation(P-ROSC)in patients with OHCA and develop a nomogram prediction model.METHODS Clinical data of patients with OHCA in Shenzhen,China,from January 2012 to December 2019 were retrospectively analyzed.Least absolute shrinkage and selection operator(LASSO)regression and multivariate logistic regression were applied to select the optimal factors predicting P-ROSC in patients with OHCA.A nomogram prediction model was established based on these influencing factors.Discrimination and calibration were assessed using receiver operating charac-teristic(ROC)and calibration curves.Decision curve analysis(DCA)was used to evaluate the model’s clinical utility.RESULTS Among the included 2685 patients with OHCA,the P-ROSC incidence was 5.8%.LASSO and multivariate logistic regression analyses showed that age,bystander cardiopulmonary resuscitation(CPR),initial rhythm,CPR duration,ventilation mode,and pathogenesis were independent factors influencing P-ROSC in these patients.The area under the ROC was 0.963.The calibration plot demonstrated that the predicted P-ROSC model was concordant with the actual P-ROSC.The good clinical usability of the prediction model was confirmed using DCA.CONCLUSION The nomogram prediction model could effectively predict the probability of P-ROSC in patients with OHCA.

The effects of hyperbaric oxygen therapy on paroxysmal sympathetic hyperactivity after cardiopulmonary resuscitation: a case series

The onset of cardiac arrest (CA) is sudden and critical.Due to cerebral ischaemia and hypoxia, the prognosis for post-cardiopulmonary resuscitation (CPR) patients is poor. Paroxysmal sympathetic hyperexcitability (PSH) is a potentially life-threatening condition, which is characterized by episodes of increased heart rate and blood pressure,sweating, hypothermia, and forced posture.[1] Hypoxicischaemic encephalopathy post-CPR can lead to PSH,which often indicates a worse prognosis.

Establishment of a Rat Model of Capillary Leakage Syndrome Induced by Cardiopulmonary Resuscitation After Cardiac Arrest

Objective:Cardiopulmonary resuscitation(CPR)after cardiac arrest(CA)is one of the main causes of capillary leakage syndrome(CLS).This study aimed to establish a stable CLS model following the CA and cardiopulmonary resuscitation(CA-CPR)model in Sprague-Dawley(SD)rats.Methods:We conducted a prospective,randomized,animal model study.All adult male SD rats were randomly divided into a normal group(group N),a sham operation group(group S),and a cardiopulmonary resuscitation group(group T).The SD rats of the three groups were all inserted with 24-G needles through their left femoral arteries and right femoral veins.In group S and group T,the endotracheal tube was intubated.In group T,CA induced by asphyxia(AACA)was caused by vecuronium bromide with the endotracheal tube obstructed for 8 min,and the rats were resuscitated with manual chest compression and mechanical ventilation.Preresuscitation and postresuscitation measurements,including basic vital signs(BVS),blood gas analysis(BG),routine complete blood count(CBC),wet-to-dry ratio of tissues(W/D),and the HE staining results after 6 h were evaluated.Results:In group T,the success rate of the CA-CPR model was 60%(18/30),and CLS occurred in 26.6%(8/30)of the rats.There were no significant differences in the baseline characteristics,including BVS,BG,and CBC,among the three groups(P>0.05).Compared with pre-asphyxia,there were significant differences in BVS,CBC,and BG,including temperature,oxygen saturation(SpO_(2)),mean arterial pressure(MAP),central venous pressure(CVP),white blood cell count(WBC),hemoglobin,hematocrit,pH,pCO_(2),pO_(2),SO_(2),lactate(Lac),base excess(BE),and Na+(P<0.05)after the return of spontaneous circulation(ROSC)in group T.At 6 h after ROSC in group T and at 6 h after surgery in groups N and S,there were significant differences in temperature,heart rate(HR),respiratory rate(RR),SpO_(2),MAP,CVP,WBC,pH,pCO_(2),Na+,and K+among the three groups(P<0.05).Compared with the other two groups,the rats in group T showed a significantly increased W/D weight ratio(P<0.05).The HE-stained sections showed consistent severe lesions in the lung,small intestine,and brain tissues of the rats at 6 h after ROSC following AACA.Conclusion:The CA-CPR model in SD rats induced by asphyxia could reproduce CLS with good stability and reproducibility.

Synchronized ventilation during resuscitation in pigs does not necessitate high inspiratory pressures to provide adequate oxygenation

The optimal ventilation method for patients suffering from cardiac arrest and receiving cardiopulmonary resuscitation(CPR)remains unclear,and the recent guidelines do not provide detailed information.[1-3]During CPR,changing thoracic pressures due to chest compressions and ventilation pressure infl uence venous return and cardiac output,respectively.[4-6]Novel mechanical ventilation modes that are synchronized to chest compressions may improve blood flow and oxygenation.[4]In this porcine trial,we investigated the feasibility of a specially designed chest compression synchronized ventilation(CCSV)mode with peak pressures limited to 40 mbar(1 mbar=0.1 kPa)and an experimental synchronized ventilation(SV)limited to 20 mbar,respectively,intended to achieve a more lung-protective ventilation pattern during resuscitation.We evaluated whether the diff erent synchronized pressure levels ameliorate hemodynamics,gas exchange and pulmonary function and compared it to intermittent positive pressure ventilation(IPPV).

Liposome-Encapsulated Hemoglobin Vesicle Improves Persistent Anti-arrhythmogenesis through Improving Myocardial Electrical Remodeling and Modulating Cardiac Autonomic Activity in a Hemorrhagic Shock-Induced Rat Heart Model

Objective Shock heart syndrome(SHS)is associated with lethal arrhythmias(ventricular tachycardia/ventricular fibrillation,VT/VF).We investigated whether liposome-encapsulated human hemoglobin vesicles(HbVs)has comparable persistent efficacy to washed red blood cells(wRBCs)for improving arrhythmogenesis in the subacute to chronic phase of SHS.Methods Optical mapping analysis(OMP),electrophysiological study(EPS),and pathological examinations were performed on blood samples from Sprague-Dawley rats following induction of hemorrhagic shock.After hemorrhagic shock,the rats were immediately resuscitated by transfusing 5%albumin(ALB),HbV,or wRBCs.All rats survived for 1 week.OMP and EPS were performed on Langendorff-perfused hearts.Spontaneous arrhythmias and heart rate variability(HRV)were evaluated using awake 24-h telemetry,cardiac function by echocardiography,and pathological examination of Connexin43.Results OMP showed significantly impaired action potential duration dispersion(APDd)in the left ventricle(LV)in the ALB group whereas APDd was substantially preserved in the HbV and wRBCs groups.Sustained VT/VF was easily provoked by EPS in the ALB group.No VT/VF was induced in the HbV and wRBCs groups.HRV,spontaneous arrhythmias,and cardiac function were preserved in the HbV and wRBCs groups.Pathology showed myocardial cell damage and Connexin43 degradation in the ALB group,all of which were attenuated in the HbV and wRBCs groups.Conclusion LV remodeling after hemorrhagic shock caused VT/VF in the presence of impaired APDd.Similar to wRBCs,HbV persistently prevented VT/VF by inhibiting persistent electrical remodeling,preserving myocardial structures,and ameliorating arrhythmogenic modifying factors in the subacute to chronic phase of hemorrhagic shock-induced SHS.

Vagus nerve stimulation protects against cerebral injury after cardiopulmonary resuscitation by inhibiting inflammation through the TLR4/NF-κB and α7nAChR/JAK2 signaling pathways

BACKGROUND: Our previous research proved that vagus nerve stimulation(VNS) improved the neurological outcome after cardiopulmonary resuscitation(CPR) by activating α7 nicotinic acetylcholine receptor(α7nAChR) in a rat model, but the underlying mechanism of VNS in neuroprotection after CPR remains unclear.METHODS: In vivo, we established a mouse model of cardiac arrest(CA)/CPR to observe the survival rate, and the changes in inflammatory factors and brain tissue after VNS treatment. In vitro, we examined the effects of α7nAChR agonist on ischemia/reperfusion(I/R)-induced inflammation in BV2 cells under oxygen-glucose deprivation/reoxygenation(OGD/R) conditions. We observed the changes in cell survival rate, the levels of inflammatory factors, and the expressions of α7nAChR/Janus kinase 2(JAK2) and toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB).RESULTS: In vivo, VNS preconditioning enhanced functional recovery, improved the survival rate, and reduced hippocampal CA1 cell damage, and the levels of inflammatory mediators after CA/CPR. The application of α7nAChR agonists provided similar effects against cerebral injury after the return of spontaneous circulation(ROSC), while α7nAChR antagonists reversed these neuroprotective impacts. The in vitro results mostly matched the findings in vivo. OGD/R increased the expression of tumor necrosis factor-alpha(TNF-α), TLR4 and NF-κB p65. When nicotine was added to the OGD/R model, the expression of TLR4, NF-κB p65, and TNF-α decreased, while the phosphorylation of JAK2 increased, which was prevented by preconditioning with α7nAChR or JAK2 antagonists.CONCLUSION: The neuroprotective effect of VNS correlated with the activation of α7nAChR. VNS may alleviate cerebral IR injury by inhibiting TLR4/NF-κB and activating the α7nAChR/JAK2 signaling pathway.

Controversies in the management of acute pancreatitis:An update

This review summarized the current controversies in the management of acute pancreatitis(AP).The controversies in management range from issues involving fluid resuscitation,nutrition,the role of antibiotics and antifungals,which analgesic to use,role of anticoagulation and intervention for complications in AP.The interventions vary from percutaneous drainage,endoscopy or surgery.Active research and emerging data are helping to formulate better guidelines.The available evidence favors crystalloids,although the choice and type of fluid resuscitation is an area of dynamic research.The nutrition aspect does not have controversy as of now as early enteral feeding is preferred most often than not.The empirical use of antibiotics and antifungals are gray zones,and more data is needed for conclusive guidelines.The choice of analgesic is being studied,and the recommendations are still evolving.The position of using anticoagulation is still awaiting consensus.The role of intervention is well established,although the modality is constantly changing and favoring endoscopy or percutaneous drainage rather than surgery.It is evident that more multicenter randomized controlled trials are required for establishing the standard of care in these crucial management issues of AP to improve the morbidity and mortality worldwide.