Systemic cooling cardiac protection

NEW FINDINGS: What is the central question of this study? Does passive heat stress attenuate the increase in cardiac parasympathetic stimulation, vascular resistance and blood pressure evoked by face cooling? What is the main finding and its importance? Passive heat stress attenuates the capacity to increase cardiac parasympathetic activation and impairs the ability to increase vascular resistance during sympathoexcitation, which ultimately results in a relative inability to increase blood pressure...

Early, prehospital cooling seeks to reduce and control the body temperature as early as possible to protect the brain and improve patient outcome in cardiac arrest, stroke, and traumatic brain injury. In this study, we investigate the feasibility of localized cooling of the porcine brain by using a novel high-flow cold air protocol, which utilizes the close proximity between the nasal cavity and the brain. Five adult pigs were anesthetized and temperature change was mapped before, during, and after cooling by using the proton resonance frequency method on a 3 T Siemens Magnetom Skyra system...

BACKGROUND: The use of mild therapeutic hypothermia (MTH) in patients after out-of-hospital cardiac arrest (OHCA) who are undergoing primary percutaneous coronary intervention (pPCI) can protect patients from thromboembolic complications. The aim of the study was to evaluate the adaptive mecha- nisms of the coagulation system in MTH-treated comatose OHCA survivors. METHODS: Twenty one comatose OHCA survivors with acute coronary syndrome undergoing imme- diate pPCI were treated with MTH...

We investigated feasibility and safety of the RhinoChill (RC) transnasal cooling system initiated before achieving a protected airway during cardiopulmonary resuscitation (CPR) in a prehospital setting.In out-of-hospital cardiac arrest (OHCA), transnasal evaporative cooling was initiated during CPR, before a protected airway was established and continued until either the patient was declared dead, standard institutional systemic cooling methods were implemented or cooling supply was empty. Patients were monitored throughout the hypothermia period until either death or hospital discharge...

UNLABELLED: Abstract PURPOSE: several therapeutic options are used in emergency situations, when heart and/or lung functions acutely fail. Because of the poor results of conventional treatments, the use of an extra-corporeal life support (ECLS) systems able to completely assume the heart and lung functions in emergency situations is becoming a viable alternative. We have developed a unique ECLS system for patients needing extended respiratory and/or circulatory support and controlled hypothermia...

OBJECTIVES: Myocardial hypertrophy represents a great challenge in cardiac surgery. Several strategies have been described to protect the hypertrophied myocardium during cardiopulmonary bypass, and aortic clamping, yet the ideal strategy has not been identified. This study investigates the use of moderate systemic hypothermia (MSH) as an adjuvant method to protect the hypertrophied myocardium in patients undergoing aortic valve replacement (AVR). METHODS: Twenty eight patients undergoing AVR were divided into two groups, (Group I) received continuous cold 5-8 °C retrograde blood cardioplegia (CRBC) and their body temperature was cooled down to 23-26 °C...

OBJECTIVES: Total liquid ventilation provides ultrafast and potently neuro- and cardioprotective cooling after shockable cardiac arrest and myocardial infarction in animals. Our goal was to decipher the effect of hypothermic total liquid ventilation on the systemic and cerebral response to asphyxial cardiac arrest using an original pressure- and volume-controlled ventilation strategy in rabbits. DESIGN: Randomized animal study. SETTING: Academic research laboratory...

Sudden cardiac arrest (SCA) is a leading cause of death in the United States. Despite return of spontaneous circulation, patients die due to post-SCA syndrome that includes myocardial dysfunction, brain injury, impaired metabolism, and inflammation. No medications improve SCA survival. Our prior work suggests that optimal Akt activation is critical for cooling protection and SCA recovery. Here, we investigate a small inhibitor of PTEN, an Akt-related phosphatase present in heart and brain, as a potential therapy in improving cardiac and neurological recovery after SCA...

Complement activation has been implicated in ischemia/reperfusion injury. This study aimed to determine whether mild hypothermia (HT) inhibits systemic and cerebral complement activation after resuscitation from cardiac arrest. Sixteen minipigs resuscitated from 8 minutes of untreated ventricular fibrillation were randomized into two groups: HT group (n=8), treated with HT (33°C) for 12 hours; and normothermia group (n=8), treated similarly as HT group except for cooling. Blood samples were collected at baseline and 0...

Postoperative pulmonary dysfunction (PPD) is a frequent and significant complication after cardiac surgery. It contributes to morbidity and mortality and increases hospitalization stay and its associated costs. Its pathogenesis is not clear but it seems to be related to the development of a systemic inflammatory response with a subsequent pulmonary inflammation. Many factors have been described to contribute to this inflammatory response, including surgical procedure with sternotomy incision, effects of general anesthesia, topical cooling, and extracorporeal circulation (ECC) and mechanical ventilation (VM)...

UNLABELLED: A 30-year-old female gravida 1 (37 weeks + 5 days gestation) underwent a crash Cesarean section for evidence of fetal distress, with the presumed diagnosis of placental abruption. Immediately post-op, the patient had a complete cardiovascular collapse with pulseless electrical activity, requiring cardiopulmonary resuscitation (CPR). Two doses of thrombolytics (Tenecteplase) were administered during the resuscitation, with a presumed diagnosis of a pulmonary embolism. After approximately 45 minutes into the resuscitation, the cardiac surgery team was called to initiate extracorporeal membrane oxygenation (ECMO)...

BACKGROUND: Extracorporeal circulation used during coronary artery bypass grafting triggers systemic inflammatory response with neutrophil activation which adversely affects ischaemic/reperfused myocardium. One method of myocardial protection during cardiac surgery is the use of blood cardioplegia. Its protective effect is related to cardiac cooling and metabolism reduction, oxygen supply from erythrocytes, and reactive oxygen species scavenging. However, blood cardioplegia is also associated with myocardial damage induced by undesirable morphotic blood elements...

BACKGROUND: Therapeutic hypothermia (TH) is used to mitigate cerebral injury after an out of hospital cardiac arrest. There is a perceived risk of increased arrhythmias with temperatures lower than the current target of 32-34°C for TH. This study sought to develop and investigate the electrophysiological changes in a sheep model of systemic hypothermia regarding the susceptibility to ventricular arrhythmias. METHODS: Ten sheep underwent systemic hypothermia using a venous-venous extra-corporeal circuit whilst instrumented with a 12 lead ECG...

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Is cerebrospinal fluid (CSF) drainage of benefit in patients undergoing surgery on the descending thoracic aorta or thoracoabdominal aorta?' Altogether 1177 papers were found using the reported search, of which 17 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated...

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: Is it worth packing the head with ice in patients undergoing deep hypothermic circulatory arrest (DHCA)? Altogether more than 34 papers were found using the reported search, of which 7 represented the best evidence to answer the clinical question, 5 of which were animal studies, 1 was a theoretical laboratory study and 1 study looked at the ability to cool using circulating water 'jackets' in humans...

The last 20 years was characterized by great improvements in the efficacy and tolerability of anticancer therapies. Most of these changes are related to the introduction of targeted drugs, which presents a better activity on the biology of cancer and less toxicity. Nevertheless, the initial enthusiasm was cooled by the emerging evidences of cardiac side effects. The aim of this review is to describe the actual knowledge about the possible cardiotoxicity of targeted drugs. The most important need is the detection of early cardiotoxicity and the evidence of subtle myocardial dysfunction that allows to begin a protective therapy...

Hypothermia is used in the clinic for protection of organs such as the brain against ischemic injury during aortic/complex congenital cardiac surgery or post-resuscitation encephalopathy. The principal mechanism of hypothermic protection is suppression of metabolism, however, the pleiotropic effects of cooling are incompletely understood. Here, we used a rat model system to evaluate metabolic changes induced by deep hypothermia. The hypothermia-induced changes were identified using fluorescence-based two-dimensional (2-D) difference gel electrophoresis (DIGE) and matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF/TOF) tandem mass spectrometry...

BACKGROUND: Out of hospital cardiac arrest is associated with a high rate of mortality, and poor neurological outcomes. Favourable neuro-protective effects are associated with induced hypothermia and international recommendations exist for therapeutic hypothermia. OBJECTIVE: This study reviews practice for therapeutic hypothermia for out of hospital cardiac arrest patients within one ICU. It aims to describe the level of adherence to the guideline, identify barriers to implementation and to improve adherence...

OBJECTIVE: To explore the molecular mechanisms by which mild hypothermia following resuscitation improves neurological function in a porcine model of cardiac arrest. METHODS: Thirty-three inbred Chinese Wuzhishan (WZS) minipigs were used. After 8 min of untreated ventricular fibrillation (VF), the surviving animals (n=29) were randomly divided into two groups including serum group (n=16) and molecular group (n=13). Serum group animals were used to measure porcine-specific tumour necrosis factor-alpha (TNF-α), interleukin (IL-6, IL-10), matrix metalloproteinase (MMP9), Aquaporin-4 (AQP4), tissue inhibitor to metalloproteinase-1 (TIMP1), neuron-specific enolase (NSE) and S100B at 0...

Due to its protective effect on the brain and the myocardium, hypothermia therapy (HT) has been extensively studied in cardiac arrest patients with coma as well as in patients presenting with acute myocardial infarction (MI). In the setting of cardiac arrest, randomized studies have shown that HT decreases mortality and improves neurological outcomes. Subsequent guidelines have therefore recommended cooling (32°C to 34°C) for 12 to 24 h in unconscious adult patients with spontaneous circulation after out-of-hospital cardiac arrest due to ventricular fibrillation...