Induction of therapeutic hypothermia during prehospital CPR using ice-cold intravenous fluid

AIM OF THE STUDY: Primarily, to investigate induction of therapeutic hypothermia during prehospital cardiopulmonary resuscitation (CPR) using ice-cold intravenous fluids. Effects on return of spontaneous circulation (ROSC), rate of rearrest, temperature and haemodynamics were assessed. Additionally, the outcome was followed until discharge from hospital. MATERIALS AND METHODS: Seventeen adult prehospital patients without obvious external causes for cardiac arrest were included. During CPR and after ROSC, paramedics infused +4 degrees C Ringer's acetate aiming at a target temperature of 33 degrees C. RESULTS: ROSC was achieved in 13 patients, 11 of whom were admitted to hospital. Their mean initial nasopharyngeal temperature was 35.17+/-0.57 degrees C (95% CI), and their temperature on hospital admission was 33.83+/-0.77 degrees C (-1.34 degrees C, p<0.001). The mean infused volume of cold fluid was 1571+/-517 ml. The rate of rearrest after ROSC was not increased compared to previous reports. Hypotension was observed in five patients. Of the 17 patients, 1 survived to hospital discharge. CONCLUSION: Induction of therapeutic hypothermia during prehospital CPR and after ROSC using ice-cold Ringer's solution effectively decreased nasopharyngeal temperature. The treatment was easily carried out and well tolerated.     

Therapeutic hypothermia induced during cardiopulmonary resuscitation using large-volume, ice-cold intravenous fluid

INTRODUCTION: Therapeutic hypothermia after resuscitation improves outcome following prolonged out-of-hospital cardiac arrest. Laboratory studies suggest that this therapy may improve outcome further when induced during cardiopulmonary resuscitation. We report a case where therapeutic hypothermia was induced during cardiopulmonary resuscitation using large-volume (40 mL/kg), ice-cold (4 degrees C) intravenous fluid. DESIGN: Case report. SETTING: A tertiary level hospital in Victoria, Australia. CASE REPORT: The patient suffered a cardiac arrest secondary to pericardial tamponade following right ventricular perforation during cardiac catheterisation. Percutaneous needle drainage was unsuccessful and open drainage via a left emergency thoracotomy was performed. Therapeutic hypothermia during cardiopulmonary resuscitation was induced using of a rapid infusion of large-volume (40 mL/kg), ice-cold (4 degrees C) crystalloid fluid. A spontaneous circulation was restored after 37 min of cardiac arrest. The patient made a satisfactory neurological recovery. CONCLUSION: Treatment with a rapid intravenous infusion of large-volume (40 mL/kg), ice-cold (4 degrees C) fluid during cardiopulmonary resuscitation induces mild hypothermia and may provide neurological protection. Further clinical studies of this approach are warranted.     

Induced hypothermia using large volume,ice-cold intravenous fluid in comatose survivors of out-of-hospital cardiac arrest: a preliminary report

STUDY HYPOTHESIS: Recent studies have shown that induced hypothermia for twelve to twenty four hours improves outcome in patients who are resuscitated from out-of-hospital cardiac arrest. These studies used surface cooling, but this technique provided for relatively slow decreases in core temperature. Results from animal models suggest that further improvements in outcome may be possible if hypothermia is induced earlier after resuscitation from cardiac arrest. We hypothesized that a rapid infusion of large volume (30 ml/kg), ice-cold (4 degrees C) intravenous fluid would be a safe, rapid and inexpensive technique to induce mild hypothermia in comatose survivors of out-of-hospital cardiac arrest. METHODS: We enrolled 22 patients who were comatose following resuscitation from out-of-hospital cardiac arrest. After initial evaluation in the Emergency Department (ED), a large volume (30 ml/kg) of ice-cold (4 degrees C) lactated Ringers solution was infused intravenously over 30 min. Data on vital signs, arterial blood gas, electrolyte and hematological was collected immediately before and after the infusion. RESULTS: The rapid infusion of large volume, ice-cold crystalloid fluid resulted in a significant decrease in median core temperature from 35.5 to 33.8 degrees C. There were also significant improvements in mean arterial blood pressure, renal function and acid-base analysis. No patient developed pulmonary odema. CONCLUSION: A rapid infusion of large volume, ice-cold crystalloid fluid is an inexpensive and effective method of inducing mild hypothermia in comatose survivors of out-of-hospital cardiac arrest, and is associated with beneficial haemodynamic, renal and acid-base effects. Further studies of this technique are warranted.     

Effects of large volume, ice-cold intravenous fluid infusion on respiratory function in cardiac arrest survivors

International guidelines for cardiopulmonary resuscitation recommend mild hypothermia (32–34 °C) for 12–24 h in comatose survivors of cardiac arrest. To induce therapeutic hypothermia a variety of external and intravascular cooling devices are available. A cheap and effective method for inducing hypothermia is the infusion of large volume, ice-cold intravenous fluid. There are concerns regarding the effects of rapid infusion of large volumes of fluid on respiratory function in cardiac arrest survivors. We have retrospectively studied the effects of high volume cold fluid infusion on respiratory function in 52 resuscitated cardiac arrest patients.The target temperature of 32–34 °C was achieved after 4.1 ± 0.5 h (cooling rate 0.48 °C/h). During this period 3427 ± 210 mL ice-cold fluid was infused. Despite significantly reduced LV-function (EF 35.8 ± 2.2%) the respiratory status of these patients did not deteriorate significantly. On intensive care unit admission the mean PaO₂ was 231.4 ± 20.6 mmHg at a F_iO₂ of 0.82 ± 0.03 (PaO₂/F_iO₂ = 290.0 ± 24.1) and a PEEP level of 7.14 ± 0.31 mbar. Until reaching the target temperature of ≤34 °C the F_iO₂ could be significantly reduced to 0.63 ± 0.03 with unchanged PEEP level (7.23 ± 0.36 mbar). Under these conditions the PaO₂/F_iO₂ ratio slightly decreased to 247.5 ± 18.5 (P = 0.0893). Continuing the saline infusion to achieve a body temperature of 33 °C, the F_iO₂ could be further reduced with unchanged PEEP.The infusion of large volume, ice-cold fluid is an effective and inexpensive method for inducing therapeutic hypothermia. Resuscitation from cardiac arrest is associated with a deterioration in respiratory function. The infusion of large volumes of cold fluid does not cause a statistically significant further deterioration in respiratory function. A larger, randomized and prospective study is required to assess the efficacy and safety of ice-cold fluid infusion for the induction of therapeutic hypothermia.     

Cholinergic enzymatic activity of cerebrospinal fluid of patients with various neurologic diseases

The cerebrospinal fluid (CSF) of normal humans contains both true and pseudocholinesterases and choline acetyl transferase (choline acetylase) detectable by radiochemical assay. Elevations of total cholinesterase, pseudocholinesterase, and true cholinesterase occur in brain tumors, meningitis, Guillain-Barre disease, hydrocephalus, and brain abscess. However, the non-specificity and inconstancy of CSF cholinesterase changes in neurologic diseases limit its clinical usefulness.     

Induction of therapeutic hypothermia after cardiac arrest in prehospital patients using ice-cold Ringer's solution: a pilot study

The cooling and haemodynamic effects of prehospital infusion of ice-cold Ringer's solution were studied in 13 adult patients after successful resuscitation from non-traumatic cardiac arrest. After haemodynamics stabilisation, 30 ml/kg of Ringer's solution was infused at a rate of 100ml/min into the antecubital vein. Arterial blood pressure and blood gases, pulse rate, end-tidal CO(2) and oesophageal temperature were monitored closely. The mean core temperature decreased from 35.8 +/- 0.9 degrees C at the start of infusion to 34.0 +/- 1.2 degrees C on arrival at hospital (P < 0.0001). No serious adverse haemodynamic effects occurred. It is concluded that the induction of therapeutic hypothermia using this technique in the prehospital setting is feasible.     

Intravenous fluid therapy in neurologic injury.

Cerebral autoregulation and the blood-brain barrier are two important mechanisms that attempt to preserve brain homeostasis. The function of either may be disrupted by injury. When autoregulation is impaired, blood pressure and hematocrit determine cerebral oxygen delivery. Injury to the blood-brain barrier impairs brain volume regulation and may contribute to cerebral edema. The choice of intravenous fluid influences cerebral blood flow, cerebral oxygen delivery, brain metabolism, and brain volume.     

Mild hypothermia therapy reduces blood glucose and lactate and improves neurologic outcomes in patients with severe traumatic brain injury

Purpose

The study aimed to investigate the association between blood glucose or lactate and the outcomes of severe traumatic brain injury (TBI), and to evaluate the effect of mild hypothermia therapy on glucose and lactate levels.

Methods

Eighty-one patients with TBI were randomly divided into normothermia (n = 41) and mild hypothermia (n = 40) group. Body temperature of hypothermia group was maintained at 32.7°C for 72 hours. Arterial blood glucose and lactic acid were determined before and after hypothermia therapy. Glasgow Outcome Scale (GOS) score was assessed 3 months after the treatment.

Results

The mean glucose (7.04 ± 0.51 vs 9.71 ± 1.63 mmol/L, P < .05) in the hypothermia group was lower than in the normothermia group after hypothermia therapy. There were more patients with good neurologic function (GOS 4-5) in the hypothermia group than in the normothermia group (75.0% vs 51.2%, P = .038). Multivariate regression analysis showed that blood glucose greater than 10 mmol/L (adjusted risk ratio, 5.7; 95% confidence interval, 1.4-13.2; P < .05) was an independent predictor for poor neurologic outcomes in these patients, and hypothermia therapy was an independent predictor for favorable outcomes (risk ratio, 4.9; 95% confidence interval, 1.0-15.6; P < .05). No significant association between lactate and GOS scores was identified in the multivariate analysis.

Conclusion

Hyperglycemia after TBI was associated with poor clinical outcomes, but the predictive value of blood lactate level requires further investigation. Hypothermia therapy improves neurologic outcomes in patients with severe TBI, and reduction in blood glucose may be partially responsible for the improved outcomes.     

Effects of therapeutic hypothermia on activity of some enzymes in cerebrospinal fluid of patients with anoxic-ischemic brain injury

I assessed the effect of therapeutic hypothermia on the activity in cerebrospinal fluid of creatine kinase (EC 2.7.3.2) and its brain isoenzyme (CK-BB), lactate dehydrogenase (EC 1.1.1.27), and aspartate aminotransferase (EC 2.6.1.1.) as markers of cerebral damage in patients with transient anoxic-ischemic brain injury. Moderate hypothermia (30-32 degrees C) lasting more than 24 h resulted in disproportionately greater activity of creatine kinase during the post-insult period than in patients not treated with hypothermia but having similar insults and outcome (p less than .01 for survivors, and p less than .005 for nonsurvivors). No differences were observed for the thermostable enzymes lactate dehydrogenase and aspartate aminotransferase, which demonstrates that the effect of hypothermia must be taken into account when thermolabile enzymes are used as sole markers of brain damage in such patients.     

亚低温辅助治疗重型颅脑外伤患者82例

目的探讨亚低温在治疗重型颅脑外伤中的应用价值。方法对连续收治的160例重型颅脑外伤患者,随机分为亚低温治疗组（n=82）和常温组（n=78）,观察两组的治疗效果。结果随访6个月,亚低温组20例轻度残疾、正常生活,24例中残,16例重残,9例植物生存,13例死亡;对照组10例轻度残疾、正常生活,18例中残,16例重残,14例植物生存,20例死亡;两组比较有统计学差异（P〈0．05）,亚低温组的治疗效果优于常温组。结论亚低温有显著的脑保护作用,能降低重型颅脑外伤患者的死残率,改善预后。     

Blood ammonia is a predictive biomarker of neurologic outcome in cardiac arrest patients treated with therapeutic hypothermia

Purpose

The aim of this study was to investigate the value of commonly examined laboratory measurements, including ammonia and lactate, in predicting neurologic outcome of out-of-hospital cardiac arrest (OHCA) patients treated with therapeutic hypothermia (TH).

Methods

This was a retrospective cohort study of patients with a return of spontaneous circulation after OHCA who were treated with TH between February 2007 and July 2010. We measured typical blood measurements on arrival at the emergency department. The subjects were classified into 2 groups: the good neurologic outcome group (Cerebral Performance Category [CPC] 1-2 at 1 month) and the poor neurologic outcome group (Cerebral Performance Category 3-5). We compared blood biomarker levels and basal characteristics between the 2 groups. Logistic regression analyses were performed to determine independent biomarkers that predict poor neurologic outcome.

Results

A total of 117 patients were included. Between the 2 groups, significantly different levels of blood measurements included hemoglobin level, pH, Pao₂, Paco₂, base excess, albumin, glucose, potassium, chloride, bilirubin, phosphorous, and ammonia. In multivariate analyses, blood ammonia level (>96 mg/dL; odds ratio [OR], 7.240; 95% confidence interval [CI], 1.718-30.512), noncardiac causes (OR, 46.215; 95% CI, 9.670-220.873), and time interval from collapse to return of spontaneous circulation (>33 min; OR, 5.943; 95% CI, 1.543-22.886) were significantly related to poor neurologic outcome.

Conclusion

Among the blood measurements on emergency department arrival, blood ammonia (>96 mg/dL) was the only independent predictive biomarker of poor neurologic outcome. Thus, higher blood ammonia level was associated with poor neurologic outcome in OHCA patients treated with TH.     

亚低温治疗对急性重型颅脑损伤患者局部脑氧饱和度及脑脊液乳酸的影响

目的 :探讨亚低温治疗对急性重型脑损伤患者局部脑氧饱和度 (r Sc O2 )、颅内压 (ICP)及脑脊液乳酸含量变化的影响。方法 :49例急性重型脑损伤患者随机分为亚低温治疗组 2 5例和常温治疗对照组 2 4例。亚低温治疗组在常规治疗基础上于伤后 2 0小时内行亚低温治疗 ,直肠温度控制在 32 .5℃～ 34 .5℃ ,持续 2～5日 ,同时监测患者生命体征、ICP、脑灌注压 (CPP)、血电解质、颈静脉血氧饱和度 (Sj O2 )、动脉血氧饱和度(Sa O2 )以及 r Sc O2 。对照组仅行常规治疗。 2组患者均于伤后 3个月时评定预后。结果 :与对照组比较 ,亚低温治疗组患者伤后早期的高颅内压、脑脊液高乳酸分别显著下降 (P<0 .0 5或 P<0 .0 1) ,显著降低的 r Sc O2 和CPP早期即上升并维持正常 (P<0 .0 1或 P<0 .0 5 ) ,而患者的生命体征、血电解质及 Sj O2 、Sa O2 无明显差异 ,且未发生严重并发症 ,病死率下降 ,预后明显改善。结论 :亚低温治疗对重型脑损伤有明显疗效 ,可显著降低病死率 ,提高生存质量 ;无创持续监测局部脑氧饱和度能反映脑伤后脑氧代谢 ,对亚低温治疗更具指导意义     

Determination of the concentration of immunoglobulins and other proteins in bronchoalveolar fluid of patients with various types of pulmonary pathology

The levels of immunoglobulins and other proteins (alpha 2-MG, alpha 1-AT, C3, albumin, transferrin and lactoferrin) were studied in the BAL of 60 patients with different types of pulmonary tuberculosis, 4 patients with sarcoidosis and 7 CNPD patients. The level of most proteins in BAL of the examinees was higher than that reported for healthy subjects. The highest protein levels were noted in CNPD and sarcoidosis patients. The diagnostic importance of the level of alpha 2-MG was established for sarcoidosis. 27 paired BAL-serum specimens from the same patients with pulmonary tuberculosis were investigated for analysis of the mechanisms of protein appearance in BAL. The protein/albumin ratio for most proteins was higher in BAL than in the respective serum. A relatively high level of proteins in the patients' BAL was probably determined by the activation of their local synthesis.     

Computed tomographic determinants of neurologic deterioration in patients with large middle cerebral artery infarctions

OBJECTIVE: To identify specific radiographic features on computed tomographic (CT) imaging that can predict neurologic deterioration in patients with large middle cerebral artery (MCA) infarctions. PATIENTS AND METHODS: We performed a 10-year retrospective review from January 1, 1991, through December 31, 2001, of medical records and CT scans of patients with large MCA infarctions. Neurologic deterioration was defied as progressive drowsiness or signs of herniation. The CT scans were grouped into 3 periods according to time after ictus. Radiographic features reviewed included hyperdense middle cerebral artery sign (HMCAS), more than a 50% loss of MCA territory, sulcal effacement, loss of lentiform nucleus or insular ribbon, and septal and pineal shift. Demographic and radiographic variables were compared by using t tests and the Fisher exact test. Prognostic values were calculated for all significant radiographic variables. RESULTS: Thirty-four CT scans in 22 patients before neurologic deterioration were compared with 47 scans obtained in 14 patients without neurologic worsening. There were no demographic differences between groups. Initial analysis revealed that early (<12 hours) involvement of more than 50% of the MCA territory (P=.047; odds ratio [OR], 14.02; 95% confidence interval [CI], 1.04-189.42) and the HMCAS at any time (P<.001; OR, 21.6; 95% CI, 3.54-130.04) were independent predictors of neurologic deterioration. The positive predictive power for early involvement of more than 50% of the MCA and the HMCAS was 0.75 and 0.91, respectively. CONCLUSION: The HMCAS and early CT evidence of more than 50% MCA involvement are predictive of neurologic deterioration in patients with large MCA infarcts.     

Predictors of poor neurologic outcome in patients after cardiac arrest treated with hypothermia: a retrospective study

Introduction

Outcome studies in patients with anoxic-ischemic encephalopathy focus on the early and reliable prediction of an outcome no better than a vegetative state or severe disability. We determined the effect of mild therapeutic hypothermia on the validity of the currently used clinical practice parameters.

Methods

We conducted a retrospective cohort study of adult comatose patients after cardiac arrest treated with hypothermia. All data were collected from medical charts and laboratory files and analyzed from the day of admission to the intensive care unit until day 7, discharge from the intensive care unit or death using the Utstein definitions for the registration of the data.

Results

We analyzed the data of 103 patients. The combination of an M1 or M2 on the Glasgow Coma Scale or absent pupillary reactions or absent corneal reflexes on day 3 was present in 80.6% of patients with an unfavourable and 11.1% of patients with a favourable outcome. The combination of M1 or M2 and absent pupillary reactions to light and absent corneal reflexes on day 3 was present in 14.9% of patients with an unfavourable and none of the patients with a favourable outcome. None of the patients with a favourable outcome had a bilaterally absent somatosensory evoked potential of the median nerve. The value of electroencephalogram patterns in predicting outcome was low, except for reactivity to noxious stimuli.

Conclusions

No single clinical or electrophysiological parameter has sufficient accuracy to determine prognosis and decision making in patients after cardiac arrest, treated with hypothermia.     

Intraoperative care of patients at risk of neurologic injury

The pathophysiology of disease states that place the patient at risk are reviewed and specific management schemes are developed. Additionally, anesthetic drugs and adjuvants are discussed with regard to their use in patients at risk of neurologic injury.     

A large hypopigmented skin lesion following extravasation of intravenous fluid

This report describes an unusual presentation and complication of extravasation of intravenous fluid in an infant who presented with a large hypopigmented skin lesion distant from the site of intravenous cannulation. The infusion was immediately discontinued and an alternate intravenous site secured. A chest radiograph revealed that the catheter was not in the external jugular vein site, and a large fluid collection was apparent over the right lateral chest wall. The hypopigmented skin lesion disappeared within 48 h, and the infant remained stable. This article serves to alert the physician to consider the extravasation of intravenous fluid as a potential cause of acute development of skin hypopigmentation in an at-risk patient.