Endovascular Cooling Research Articles

Rebound Hyperthermia in Exertional Heat Stroke.

Exertional heat stroke (EHS) is a life-threatening condition requiring rapid reversal of hyperthermia to prevent poor health outcomes. Current treatment protocols aim for a cooling rate of 0.15 C/min using various modalities. This case report details a 22-year-old male who, despite initial successful cooling measures, experienced rebound hyperthermia, necessitating the use of endovascular cooling (EVC). The patient collapsed during a 19.3 km (12-mile) ruck march in Fort Moore, Georgia, with an initial core temperature of 41.6ºC. Conventional cooling methods, including ice sheets and chilled intravenous saline, adequately cooled the patient to target temperatures; however, discontinuation of cooling methods resulted in rebound hyperthermia. Endovascular cooling was eventually initiated, resulting in euthermia after 36 hours of continued use. During his hospital admission, the patient was evaluated thoroughly for underlying etiologies contributing to his rebound hyperthermia. This workup did not yield any concerning pathology, except for bilateral foot cellulitis noted on physical examination, which was subsequently managed with antibiotics. Despite initial complications, the patient recovered within 5 days and returned to duty after 2 months. Several case reports have been published regarding the use of EVC in the management of EHS. These reports, however, describe its use in initial management of EHS or in cases where hyperthermia was refractory to other conventional cooling methods. To our knowledge, this is the first report of its kind highlighting its successful implementation in rebound hyperthermia. Early recognition and initiation of cooling measures are critical in EHS cases. Future directions include developing EHS-specific EVC protocols for patients experiencing refractory or rebound hyperthermia.

Impact of cooling method on the outcome of initial shockable or non-shockable out of hospital cardiac arrest patients receiving target temperature management: a nationwide multicentre cohort study

BackgroundLittle is known about the effectiveness of surface cooling (SC) and endovascular cooling (EC) on the outcome of out-of-hospital cardiac arrest (OHCA) patients receiving target temperature management (TTM) according to their initial rhythm.MethodsWe retrospectively analysed data from the Japanese Association for Acute Medicine Out‐of‐Hospital Cardiac Arrest registry, a multicentre, prospective nationwide database in Japan. For our analysis, OHCA patients aged ≥ 18 years who were treated with TTM between June 2014 and December 2017 were included. The primary outcome was 30-day survival with favourable neurological outcome defined as a Glasgow–Pittsburgh cerebral performance category score of 1 or 2. Cooling methods were divided into the following groups: SC (ice packs, fans, air blankets, and surface gel pads) and EC (endovascular catheters and any dialysis technique). We investigated the efficacy of the two categories of cooling methods in two different patient groups divided according to their initially documented rhythm at the scene (shockable or non-shockable) using multivariable logistic regression analysis and propensity score analysis with inverse probability weighting (IPW).ResultsIn the final analysis, 1082 patients were included. Of these, 513 (47.4%) had an initial shockable rhythm and 569 (52.6%) had an initial non-shockable rhythm. The proportion of patients with favourable neurological outcomes in SC and EC was 59.9% vs. 58.3% (264/441 vs. 42/72), and 11.8% (58/490) vs. 21.5% (17/79) in the initial shockable patients and the initial non-shockable patients, respectively. In the multivariable logistic regression analysis, differences between the two cooling methods were not observed among the initial shockable patients (adjusted odd ratio [AOR] 1.51, 95% CI 0.76–3.03), while EC was associated with better neurological outcome among the initial non-shockable patients (AOR 2.21, 95% CI 1.19–4.11). This association was constant in propensity score analysis with IPW (OR 1.40, 95% CI 0.83–2.36; OR 1.87, 95% CI 1.01–3.47 among the initial shockable and non-shockable patients, respectively).ConclusionWe suggested that the use of EC was associated with better neurological outcomes in OHCA patients with initial non-shockable rhythm, but not in those with initial shockable rhythm. A TTM implementation strategy based on initial rhythm may be important.

Effects of endovascular and surface cooling on resuscitation in patients with cardiac arrest and a comparison of effectiveness, stability, and safety: a systematic review and meta-analysis

ObjectivesThis study conducted a meta-analysis to assess the effectiveness, stability, and safety of mild therapeutic hypothermia (TH) induced by endovascular cooling (EC) and surface cooling (SC) and its effect on ICU, survival rate, and neurological function integrity in adult CA patients.MethodsWe developed inclusion criteria, intervention protocols, results, and data collection. The results included outcomes during target temperature management as well as ICU stay, survival rate, and neurological functional integrity. The characteristics of the included population and each study were analyzed.ResultsFour thousand nine hundred thirteen participants met the inclusion criteria. Those receiving EC had a better cooling efficiency (cooling rates MD = 0.31[0.13, 0.50], p < 0.01; induced cooling times MD = − 90.45[− 167.57, − 13.33], p = 0.02; patients achieving the target temperature RR = 1.60[1.19, 2.15], p < 0.01) and thermal stability during the maintenance phase (maintenance time MD = 2.35[1.22, 3.48], p < 0.01; temperature fluctuation MD = − 0.68[− 1.03, − 0.33], p < 0.01; overcooling RR = 0.33[0.23, 0.49], p < 0.01). There were no differences in ICU survival rate (RR = 1.22[0.98, 1.52], p = 0.07, I2 = 0%) and hospital survival rate (RR = 1.02 [0.96, 1.09], p = 0.46, I2 = 0%), but EC reduced the length of stay in ICU (MD = − 1.83[− 3.45, − 0.21], p = 0.03, I2 = 49%) and improved outcome of favorable neurological function at discharge (RR = 1.15[1.04, 1.28], p < 0.01, I2 = 0%). EC may delay the hypothermia initiation time, and there was no significant difference between the two cooling methods in the time from the start of patients’ cardiac arrest to achieve the target temperature (MD = − 46.64[− 175.86, 82.58]). EC was superior to non-ArcticSun in terms of cooling efficiency. Although there was no statistical difference in ICU survival rate, ICU length of stay, and hospitalization survival rate, in comparison to non-ArcticSun, EC improved rates of neurologically intact survival (RR = 1.16 [1.01, 1.35], p = 0.04, I2 = 0%).ConclusionsAmong adult patients receiving cardiopulmonary resuscitation, although there is no significant difference between the two cooling methods in the time from the start of cardiac arrest to achieve the target temperature, the faster cooling rate and more stable cooling process in EC shorten patients’ ICU hospitalization time and help more patients obtain good neurological prognosis compared with patients receiving SC. Meanwhile, although EC has no significant difference in patient outcomes compared with ArcticSun, EC has improved rates of neurologically intact survival.

Endovascular Cooling Method for Hypothermia in Injured Swine.

We evaluated an endovascular cooling method to modulate core temperature in trauma swine models with and without fluid support. Anesthetized swine (N = 80) were uninjured (SHAM) or injured through a bone fracture plus soft tissue injury or an uncontrolled hemorrhage and then subdivided to target body temperatures of 38°C (normothermia) or 33°C (hypothermia) by using a Thermogard endovascular cooling device (Zoll Medical). Temperature regulation began simultaneously at onset of injury (T0). Body temperatures were recorded from a rectal probe (Rec Temp) and from a central pulmonary artery catheter (PA Temp). At T15, swine received 500 mL IV Hextend over 30 minutes or no treatment (NONE) with continued monitoring until 3 hours from injury. Hypothermia was attained in 105 ± 39 minutes, at a cooling rate of -0.061°C ± 0.007°C/min for NONE injury groups. Postinjury Hextend administration resulted in faster cooling (-0.080°C ± 0.006°C/min); target temperature was reached in 83 ± 11 minutes (p < 0.05). During active cooling, body temperature measured by the PA Temp was significantly cooler than the Rec Temp due to the probe's closer proximity to the blood-cooling catheter balloons (p < 0.05). This difference was smaller in SHAM and fluid-supported injury groups (1.1°C ± 0.4°C) versus injured NONE groups (2.1°C ± 0.3°C). Target temperatures were correctly maintained thereafter in all groups. In normothermia groups, there was a small initial transient overshoot to maintain 38°C. Despite the noticeable difference between PA Temp and Rec Temp until target temperature was attained, this endovascular method can safely induce moderate hypothermia in anesthetized swine. However, likely due to their compromised hemodynamic state, cooling in hypovolemic and/or injured patients will be different from those without injury or those that also received fluids.

Risk of thromboembolic events with endovascular cooling catheters in patients with subarachnoid hemorrhage.

Endovascular cooling is currently used for hypothermia treatment and fever reduction therapy. At the same time, little is known about the risks associated to endovascular cooling in patients treated with an endovascular cooling catheter (ECC). A retrospective chart review of 122 patients with subarachnoid hemorrhage (SAH) treated with an ECC either for therapeutic hypothermia or for fever reduction was performed. ECC-associated thromboembolic events (TEE) such as pulmonary embolism and thrombosis were recorded and compared between patients treated with an ECC and patients treated only with a central venous line (CVL). Additionally, various laboratory parameters were recorded to determine if they might be related to the frequency of TEE's. 43 Patients were treated with an ECC and 79 with a CVL. Patients in the ECC group suffered more frequently from TEE (37 %) than those with a CVL (5 %). None of the laboratory parameters was associated with an increased TEE risk. The treatment with an ECC alone was a risk factor for a TEE, independent from age as well as from Hunt and Hess grade. Our data show that the treatment with ECC increases the risk of TEE in SAH patients. Therefore, especially when considered for fever reduction, non-invasive devices for surface cooling should be the first choice.

Accidental Cannulation of the Ascending Lumbar Vein during Placement of an Endovascular Femoral Venous Cooling Catheter

Accidental Cannulation of the Ascending Lumbar Vein during Placement of an Endovascular Femoral Venous Cooling Catheter

Endovascular Cooling for Severe Hyperthermia in Cervical Spine Injury

Sustained severe hyperthermia in patients with high cervical spinal cord injuries may have many etiologies, from infection to autonomic dysregulation. When uncontrolled, it has been seen to have a high morbidity and mortality. We present two patients with high cervical spinal cord injury (SCI) who had sustained severe hyperpyrexia, of possible autonomic origin. The temperature stayed above 40°C and was uncontrolled with conventional methods of temperature management. We employed endovascular cooling for therapeutic normothermia which was successful in effective control of temperature in both the patients. The first patient suffered complications from deep vein thrombosis and pulmonary embolism which may be attributed to the presence of the cooling catheter in spite of chemical and mechanical thromboprophylaxis. The use of endovascular cooling in the management of severe life threatening hyperthermia in patients with cervical SCI may be an useful intervention. There must be a high suspicion for the possibility of deep vein thrombosis in this subgroup, however.

Therapeutic Hypothermia after Cardiac Arrest: A Retrospective Comparison of Surface and Endovascular Cooling Techniques

Therapeutic Hypothermia after Cardiac Arrest: A Retrospective Comparison of Surface and Endovascular Cooling Techniques

A Pilot Study of Rapid Cooling by Cold Saline and Endovascular Cooling Before Reperfusion in Patients With ST-Elevation Myocardial Infarction

Experimental studies have shown that induction of hypothermia before reperfusion of acute coronary occlusion reduces infarct size. Previous clinical studies, however, have not been able to show this effect, which is believed to be mainly because therapeutic temperature was not reached before reperfusion in the majority of the patients. We aimed to evaluate the safety and feasibility of rapidly induced hypothermia by infusion of cold saline and endovascular cooling catheter before reperfusion in patients with acute myocardial infarction. Twenty patients with acute myocardial infarction scheduled to undergo primary percutaneous coronary intervention were enrolled in this prospective, randomized study. After 4 ± 2 days, myocardium at risk and infarct size were assessed by cardiac magnetic resonance using T2-weighted imaging and late gadolinium enhancement imaging, respectively. A core body temperature of <35°C (34.7 ± 0.3°C) was achieved before reperfusion without significant delay in door-to-balloon time (43 ± 7 minutes versus 40 ± 6 minutes, hypothermia versus control, P=0.12). Despite similar duration of ischemia (174 ± 51 minutes versus 174 ± 62 minutes, hypothermia versus control, P=1.00), infarct size normalized to myocardium at risk was reduced by 38% in the hypothermia group compared with the control group (29.8 ± 12.6% versus 48.0 ± 21.6%, P=0.041). This was supported by a significant decrease in both peak and cumulative release of Troponin T in the hypothermia group (P=0.01 and P=0.03, respectively). The protocol demonstrates the ability to reach a core body temperature of <35°C before reperfusion in all patients without delaying primary percutaneous coronary intervention and that combination hypothermia as an adjunct therapy in acute myocardial infarction may reduce infarct size at 3 days as measured by MRI. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00417638.

Efficacy and Safety of Endovascular Cooling After Cardiac Arrest: Cohort Study and Bayesian Approach

Efficacy and Safety of Endovascular Cooling After Cardiac Arrest: Cohort Study and Bayesian Approach

Performance Characteristics of Endovascular Cooling Devices for Inducing Hypothermia after Cardiac Arrest

Performance Characteristics of Endovascular Cooling Devices for Inducing Hypothermia after Cardiac Arrest

Therapeutic Hypothermia after Cardiac Arrest: Performance Characteristics and Safety of Surface Cooling with or without Endovascular Cooling

Various methods are available to induce and maintain therapeutic hypothermia after cardiac arrest, but little data is available comparing device-mediated cooling to simple surface methods in this setting. To assess the performance characteristics of simple surface cooling with or without an endovascular cooling catheter system, we retrospectively reviewed all cases of hypothermia for comatose survivors of cardiac arrest treated at a single academically affiliated urban hospital. Forty two comatose survivors of cardiac arrest were treated over a 3.5-year period. Hypothermia was induced and maintained by simple surface methods (ice packs, cooling blankets) with or without placement of an endovascular cooling catheter system with automated temperature feedback regulation. Overall, the rate of active cooling was not different between patients treated with endovascular catheter-assisted hypothermia and patients treated with surface cooling alone. However, use of a larger (14 F) catheter was associated with faster cooling rates. Maintenance of goal temperature (33 degrees C) was far better controlled with the use of a cooling catheter. Use of surface cooling alone was associated with significant temperature overshoot. Patients treated with surface cooling alone spent more time bradycardic. Use of an endovascular cooling catheter as part of a treatment protocol for hypothermia after cardiac arrest provides better control during maintenance of hypothermia, preventing temperature overshoot. Active cooling rates may be enhanced by the use of a larger cooling catheter.

Increased Risk of Deep Venous Thrombosis with Endovascular Cooling in Patients with Traumatic Head Injury

Endovascular therapeutic hypothermia has been shown to preserve neurological function and improve outcomes; however, its use and potential complications have not been fully described in patients with traumatic head injuries. We believe that the use of endovascular cooling leads to deep venous thrombosis (DVT) in this high-risk population. We performed a retrospective review of 11 patients with severe head injuries admitted to our Level I trauma center surgical intensive care unit who underwent intravascular cooling. Duplex sonograms were obtained after 4 days at catheter removal or with clinical symptoms that were suspicious for DVT. Patients had a mean age of 23.2 (range, 16-42) years and an Injury Severity Score of 31.9 (range, 25-43). The overall incidence of DVT was 50 per cent. The DVT rate was 33 per cent if catheters were removed in 4 days or less and 75 per cent if removed after 4 days (risk ratio = 2.25; odds ratio = 6; P = ns). An elevated international normalized ratio upon admission was protective against DVT (no DVT = 1.26 vs DVT = 1.09; P = 0.02). Inferior vena cava filters were placed in most patients with DVT. The use of endovascular cooling catheters is associated with increased risk of DVT in patients with traumatic head injuries. Therefore, we discourage the use of endovascular cooling devices in this patient population.

Efficacy and Safety of Endovascular Cooling After Cardiac Arrest: Cohort Study and Bayesian Approach

Efficacy and Safety of Endovascular Cooling After Cardiac Arrest: Cohort Study and Bayesian Approach

Efficacy and Safety of Endovascular Cooling After Cardiac Arrest

Recently 2 randomized trials in comatose survivors of cardiac arrest documented that therapeutic hypothermia improved neurological recovery. The narrow inclusion criteria resulted in an international recommendation to cool only a restricted group of primary cardiac arrest survivors. In this retrospective cohort study we investigated the efficacy and safety of endovascular cooling in unselected survivors of cardiac arrest. Consecutive comatose survivors of cardiac arrest, who were either cooled for 24 hours to 33 degrees C with endovascular cooling or treated with standard postresuscitation therapy, were analyzed. Complication data were obtained by retrospective chart review. Patients in the endovascular cooling group had 2-fold increased odds of survival (67/97 patients versus 466/941 patients; odds ratio 2.28, 95% CI, 1.45 to 3.57; P<0.001). After adjustment for baseline imbalances the odds ratio was 1.96 (95% CI, 1.19 to 3.23; P=0.008). When discounting the observational data in a Bayesian analysis by using a sceptical prior the posterior odds ratio was 1.61 (95% credible interval, 1.06 to 2.44). In the endovascular cooling group, 51/97 patients (53%) survived with favorable neurology as compared with 320/941 (34%) in the control group (odds ratio 2.15, 95% CI, 1.38 to 3.35; P=0.0003; adjusted odds ratio 2.56, 1.57 to 4.17). There was no difference in the rate of complications except for bradycardia. Endovascular cooling improved survival and short-term neurological recovery compared with standard treatment in comatose adult survivors of cardiac arrest. Temperature control was effective and safe with this device.

Comparison of Endovascular and Surface Cooling During Unruptured Cerebral Aneurysm Repair

Comparison of Endovascular and Surface Cooling During Unruptured Cerebral Aneurysm Repair

Safety and Efficacy of the SetPointTM Endovascular Cooling Catheter in Swine

Safety and Efficacy of the SetPointTM Endovascular Cooling Catheter in Swine