Coagulopathy during cardiac arrest and resuscitation in a swine model of electrically induced ventricular fibrillation

SHock-INduced Endotheliopathy (SHINE): A mechanistic justification for viscoelastography-guided resuscitation of traumatic and non-traumatic shock

Irrespective of the reason for hypoperfusion, hypocoagulable and/or hyperfibrinolytic hemostatic aberrancies afflict up to one-quarter of critically ill patients in shock. Intensivists and traumatologists have embraced the concept of SHock-INduced Endotheliopathy (SHINE) as a foundational derangement in progressive shock wherein sympatho-adrenal activation may cause systemic endothelial injury. The pro-thrombotic endothelium lends to micro-thrombosis, enacting a cycle of worsening perfusion and increasing catecholamines, endothelial injury, de-endothelialization, and multiple organ failure. The hypocoagulable/hyperfibrinolytic hemostatic phenotype is thought to be driven by endothelial release of anti-thrombogenic mediators to the bloodstream and perivascular sympathetic nerve release of tissue plasminogen activator directly into the microvasculature. In the shock state, this hemostatic phenotype may be a counterbalancing, yet maladaptive, attempt to restore blood flow against a systemically pro-thrombotic endothelium and increased blood viscosity. We therefore review endothelial physiology with emphasis on glycocalyx function, unique biomarkers, and coagulofibrinolytic mediators, setting the stage for understanding the pathophysiology and hemostatic phenotypes of SHINE in various etiologies of shock. We propose that the hyperfibrinolytic phenotype is exemplified in progressive shock whether related to trauma-induced coagulopathy, sepsis-induced coagulopathy, or post-cardiac arrest syndrome-associated coagulopathy. Regardless of the initial insult, SHINE appears to be a catecholamine-driven entity which early in the disease course may manifest as hyper- or hypocoagulopathic and hyper- or hypofibrinolytic hemostatic imbalance. Moreover, these hemostatic derangements may rapidly evolve along the thrombohemorrhagic spectrum depending on the etiology, timing, and methods of resuscitation. Given the intricate hemochemical makeup and changes during these shock states, macroscopic whole blood tests of coagulative kinetics and clot strength serve as clinically useful and simple means for hemostasis phenotyping. We suggest that viscoelastic hemostatic assays such as thromboelastography (TEG) and rotational thromboelastometry (ROTEM) are currently the most applicable clinical tools for assaying global hemostatic function-including fibrinolysis-to enable dynamic resuscitation with blood products and hemostatic adjuncts for those patients with thrombotic and/or hemorrhagic complications in shock states.

Minimally invasive beating heart technique for mitral valve surgery in patients with previous sternotomy and giant left ventricle

PURPOSE

To analyze the efficacy of minimally invasive beating heart technique for mitral valve surgery in the cardiac patients with previous sternotomy and giant left ventricle.

METHODS

Eighty cardiac patients with previous sternotomy and giant left ventricle according to the diagnostic criteria that left ventricular end diastolic diameter (LVEDD) was ≥70 mm, who underwent mitral valve surgery at our center from January 2006 to January 2019 were analyzed. We divided all patients into minimally invasive beating heart technique group (n = 30) and conventional median resternotomy arrested heart technique group (n = 50) according to the surgical methods. Preoperative, intraoperative, and postoperative variables were compared between two groups.

RESULTS

Minimally invasive beating heart technique compared to the conventional median resternotomy arrested heart technique for mitral valve surgery in the cardiac patients with previous sternotomy and giant left ventricle had significant differences in operation time(P = 0.002), cardiopulmonary bypass (CPB) time(P < 0.001), intraoperative blood loss(P < 0.001), postoperative transfusion ratio(P = 0.01), postoperative transfusion amount(P < 0.001), postoperative drainage volume(P = 0.001), extubation time(P = 0.04), intensive care unit (ICU) stay time(P = 0.04) and postoperative hospital stay time(P < 0.001), but no significant differences in re-exploration for bleeding, postoperative 30-day mortality, postoperative complications and 6 months postoperative echocardiographic parameters.

CONCLUSIONS

Using the method of minimally invasive beating heart technique for mitral valve surgery in the cardiac patients with previous sternotomy and giant left ventricle is effective and reliable, meanwhile reduce the operation time and CPB time, decrease the transfusion ratio and transfusion amount, shorten postoperative ICU stay and hospital stay time, promote the early extubation so that accelerate the patients' early recovery. All of these show a benefit of minimally invasive beating heart technique compared to conventional median resternotomy arrested heart technique.

[A new method for establishing a ventricular fibrillation model by TCEI in Tibetan miniature pig]

OBJECTIVE

To explore an economical, convenient, safe and efficient method for establishing a Tibetan miniature pig model of cardiac arrest (CA).

METHODS

Cardiac puncture was performed in 12 Tibetan miniature pigs using two acupuncture needles. One needle was inserted into the fourth intercostal near the right side of the sternum about 3 cm in depth at an angle of 30° to 60° between the chest and the needle, and the depth was adjusted until the handle of the needle vibrated with the heartbeat without premature ventricular contraction on the electrocardiogram; the other was inserted into the subcutaneous tissue of the left armpit about 3 cm in depth without damaging important organs. The handles of the two needles were connected with 9V dry batteries to form a circuit and generate direct current stimulation. Ventricular fibrillation was produced in the pigs to induce CA by stimulation of transcutaneous electrical induction (TCEI) for 3 s, and the success rate of modeling was recorded. After an interval of 4 min without intervention, cardiopulmonary resuscitation (CPR) was performed using the standard Utstein style, and the survival of the pigs after recovery was observed.

RESULTS

The success rate of ventricular fibrillation modeling was 91.67% (11/12) using this method, and CPR achieved a success rate of 45.45% (5/11) in these models. The subsequent survival of the pigs was 100% (5/5) at 24 h and 80% (4/5) at 72 h. After observation for 72 h, the resuscitated Tibetan miniature pigs were dissected, and no significant damage was found in the vital organs in the thoracic or abdominal cavities.

CONCLUSIONS

We successfully established a model of CA using acupuncture needles and dry batteries in Tibetan miniature pigs, and this method is economical, convenient, safe and efficient.

Anticoagulation therapy could improve the restoration of sinus rhythm and spontaneous circulation in hospital patients with CPR

Objective

To analyse the role of anticoagulation therapy in cardiopulmonary resuscitation (CPR) following an in-hospital cardiac arrest.

Methods

This single-centre retrospective cohort study enrolled patients treated with in-hospital CPR that met the inclusion and exclusion criteria. The patients were divided into a without anticoagulation group and an anticoagulation group. The main outcome measures were the restoration of spontaneous respiration, restoration of sinus rhythm (ROSR), restoration of spontaneous circulation (ROSC) and the hospital mortality.

Results

The study analysed 344 patients: 272 in the without anticoagulation group and 72 in the anticoagulation group. Multiple logistic regression analyses demonstrated that anticoagulation therapy improved ROSR (adjusted odds ratio [OR] 2.21, 95% confidence interval [CI] 1.23, 3.96) and ROSC (adjusted OR 1.91, 95% CI 1.08, 3.40), but it did not improve the restoration of spontaneous respiration (adjusted OR 1.64, 95% CI 0.72, 3.76) and hospital survival (adjusted OR 0.90, 95% CI 0.40, 1.99).

Conclusion

Anticoagulation therapy improved ROSR and ROSC, but did not decrease the mortality rate of hospitalized patients undergoing CPR following in-hospital cardiac arrest.

Disseminated intravascular coagulation in cardiac arrest and resuscitation

The aims of this review are to demonstrate that the changes in coagulation and fibrinolysis observed in cardiac arrest and resuscitation can be recognized as disseminated intravascular coagulation (DIC), and to discuss the probability of DIC being a therapeutic target. The appearance of triggers of DIC, such as damage-associated molecular patterns, inflammatory cytokines, and adrenaline, is associated with platelet activation, marked thrombin generation and fibrin formation, insufficient anticoagulation pathways, and increased fibrinolysis by tissue-type plasminogen activator, followed by the suppression of fibrinolysis by plasminogen activator inhibitor-1, in patients with cardiac arrest and resuscitation. Simultaneous neutrophil activation and endothelial injury associated with glycocalyx perturbation have been observed in these patients. The degree of these changes is more severe in patients with prolonged precardiac arrest hypoxia and long no-flow and low-flow times, patients without return of spontaneous circulation, and non-survivors. Animal and clinical studies have confirmed decreased cerebral blood flow and microvascular fibrin thrombosis in vital organs, including the brain. The clinical diagnosis of DIC in patients with cardiac arrest and resuscitation is associated with multiple organ dysfunction, as assessed with the sequential organ failure assessment score, and increased mortality. This review confirms that the coagulofibrinolytic changes in cardiac arrest and resuscitation meet the definition of DIC proposed by the ISTH, and that DIC is associated with organ dysfunction and poor patient outcomes. This evidence implies that established DIC should be considered to be one of the main therapeutic targets in post-cardiac arrest syndrome.

Effect of ultrasonography and fluoroscopic guidance on the incidence of complications of cannulation in extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest: a retrospective observational study

BACKGROUND

It remains unclear which cannulation method is best in cases of extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest. We assessed the effect of ultrasound- and fluoroscopy-guided percutaneous cannulation on complication incidence, compared with that using only ultrasound guidance.

METHODS

This single-center retrospective observational study was conducted between February 2011 and December 2015. In the comparison group, cannulation was performed percutaneously using only ultrasound guidance. In the exposure group, cannulation was performed percutaneously using fluoroscopy and ultrasound guidance. The primary outcome assessed was whether complications were associated with cannulation. The secondary outcome assessed was the duration from hospital arrival to extracorporeal circulation start. In addition to univariate analysis, multivariate logistic-regression analysis for cannulation complications was performed to adjust for several presumed confounders.

RESULTS

Of the patients who underwent ECPR, 73 were eligible; the comparison group included 50 cases and the exposure group included 23 cases. Univariate analysis showed that the complication incidence of the exposure group was significantly lower than that of the comparison group (8.7 vs. 36.0%, p = 0.022). Duration from hospital arrival to extracorporeal circulation start was almost the same in both groups (median, 17.0 min vs. 17.0 min, p = 0.92). After multivariate logistic regression analysis, cannulation using fluoroscopy and ultrasound was independently associated with a lower complication incidence (adjusted odds ratio, 0.14; p = 0.024).

CONCLUSIONS

Ultrasound- and fluoroscopy-guided cannulation may reduce the complication incidence of cannulation without delaying extracorporeal circulation start.

Thrombolytic-Enhanced Extracorporeal Cardiopulmonary Resuscitation After Prolonged Cardiac Arrest

OBJECTIVE

To investigate the effects of the combination of extracorporeal cardiopulmonary resuscitation and thrombolytic therapy on the recovery of vital organ function after prolonged cardiac arrest.

DESIGN

Laboratory investigation.

SETTING

University laboratory.

SUBJECTS

Pigs.

INTERVENTIONS

Animals underwent 30-minute untreated ventricular fibrillation cardiac arrest followed by extracorporeal cardiopulmonary resuscitation for 6 hours. Animals were allocated into two experimental groups: t-extracorporeal cardiopulmonary resuscitation (t-ECPR) group, which received streptokinase 1 million units, and control extracorporeal cardiopulmonary resuscitation (c-ECPR), which did not receive streptokinase. In both groups, the resuscitation protocol included the following physiologic targets: mean arterial pressure greater than 70 mm Hg, cerebral perfusion pressure greater than 50 mm Hg, PaO2 150 ± 50 torr (20 ± 7 kPa), PaCO2 40 ± 5 torr (5 ± 1 kPa), and core temperature 33°C ± 1°C. Defibrillation was attempted after 30 minutes of extracorporeal cardiopulmonary resuscitation.

MEASUREMENTS AND MAIN RESULTS

A cardiac resuscitability score was assessed on the basis of success of defibrillation, return of spontaneous heart beat, weanability from extracorporeal cardiopulmonary resuscitation, and left ventricular systolic function after weaning. The addition of thrombolytic to extracorporeal cardiopulmonary resuscitation significantly improved cardiac resuscitability (3.7 ± 1.6 in t-ECPR vs 1.0 ± 1.5 in c-ECPR). Arterial lactate clearance was higher in t-ECPR than in c-ECPR (40% ± 15% vs 18% ± 21%). At the end of the experiment, the intracranial pressure was significantly higher in c-ECPR than in t-ECPR. Recovery of brain electrical activity, as assessed by quantitative analysis of electroencephalogram signal, and ischemic neuronal injury on histopathologic examination did not differ between groups. Animals in t-ECPR group did not have increased bleeding complications, including intracerebral hemorrhages.

CONCLUSIONS

In a porcine model of prolonged cardiac arrest, t-ECPR improved cardiac resuscitability and reduced brain edema, without increasing bleeding complications. However, early electroencephalogram recovery and ischemic neuronal injury were not improved.

An Effective and Reproducible Model of Ventricular Fibrillation in Crossbred Yorkshire Swine (Sus scrofa) for Use in Physiologic Research

Transcutaneous electrical induction (TCEI) has been used to induce ventricular fibrillation (VF) in laboratory swine for physiologic and resuscitation research. Many studies do not describe the method of TCEI in detail, thus making replication by future investigators difficult. Here we describe a detailed method of electrically inducing VF that was used successfully in a prospective, experimental resuscitation study. Specifically, an electrical current was passed through the heart to induce VF in crossbred Yorkshire swine (n = 30); the current was generated by using two 22-gauge spinal needles, with one placed above and one below the heart, and three 9V batteries connected in series. VF developed in 28 of the 30 pigs (93%) within 10 s of beginning the procedure. In the remaining 2 swine, VF was induced successfully after medial redirection of the superior parasternal needle. The TCEI method is simple, reproducible, and cost-effective. TCEI may be especially valuable to researchers with limited access to funding, sophisticated equipment, or colleagues experienced in interventional cardiology techniques. The TCEI method might be most appropriate for pharmacologic studies requiring VF, VF resulting from the R-on-T phenomenon (as in prolonged QT syndrome), and VF arising from other ectopic or reentrant causes. However, the TCEI method does not accurately model the most common cause of VF, acute coronary occlusive disease. Researchers must consider the limitations of TCEI that may affect internal and external validity of collected data, when designing experiments using this model of VF.

Perimortem cesarean section for maternal and fetal salvage: concise review and protocol

Cardiopulmonary arrest is a rare event during pregnancy and labor. Perimortem cesarean section has been resorted to as a rare event since ancient times; however, greater awareness regarding this procedure within the medical community has only emerged in the past few decades. Current recommendations for maternal resuscitation include performance of the procedure after five minutes of unsuccessful cardiopulmonary resuscitation. If accomplished in a timely manner, perimortem cesarean section can result in fetal salvage and is also critical for maternal resuscitation. Nevertheless, deficits in knowledge about this procedure are common. We have reviewed publications on perimortem cesarean section and present the most recent evidence on this topic, as well as recommending our "easy-to-access protocol" adapted for resuscitation following maternal collapse.

Hyperfibrinolysis is common in out-of-hospital cardiac arrest: results from a prospective observational thromboelastometry study

BACKGROUND

Cardiocirculatory arrest (CCA) activates procoagulant pathways. It has also been reported to inhibit fibrinolysis, resulting in fibrin deposition and further impairment of blood flow. Until now, no studies have used whole-blood viscoelastic tests to characterize coagulation and the impact of fibrinolysis in out-of-hospital cardiac arrest (OHCA).

METHODS

Patient with established OHCA who underwent cardiopulmonary resuscitation (CPR) were enrolled. Blood samples were obtained immediately after placement of an intravenous line at the scene, for full blood cell count, standard coagulation tests and rotational thromboelastometric (ROTEM(®)) analyses. Patients with return of spontaneous circulation (ROSC) were compared to non-ROSC patients.

RESULTS

Fifty-three patients (median age 67 years, interquartile range: 56-73 years) were included in the study. ROSC was established in 25 patients. Prothrombin time index (PTI) was significantly lower and activated partial thromboplastin time (aPTT) was significantly prolonged in non-ROSC patients compared to ROSC patients. Clotting time (CT) in the extrinsically activated ROTEM test (EXTEM) was significantly longer in non-ROSC versus ROSC patients. For the remaining EXTEM parameters, there were no significant differences between ROSC and non-ROSC patients. Hyperfibrinolysis (maximum lysis>15% according to ROTEM test results) was observed in 19 patients (35.8%). There was no difference between ROSC and non-ROSC patients in the incidence of hyperfibrinolysis.

CONCLUSIONS

PTI, aPTT and EXTEM CT revealed significant differences between ROSC and non-ROSC patients. Hyperfibrinolysis according to ROTEM test results was much more common than previously assumed. Routine use of fibrinolytic therapy in all patients with prolonged CPR cannot therefore be recommended.