Safety of thrombolysis during cardiopulmonary resuscitation

A case of massive pulmonary embolism causing cardiac arrest managed with successful systemic thrombolytic in the emergency department

Pulmonary Embolism (PE), when complicated by cardiac arrest, is almost always fatal despite all resuscitative efforts. However, a more favorable is possible when PE is rapidly identified as the cause of cardiac arrest and pulmonary circulation is quickly re-established by specific therapy. A 54-year-old woman was brought to the Emergency Department (ED) by 112 emergency ambulance service with the complaint of shortness of breath that had started 2 hours ago. She developed cardiac arrest while being physical examined 2 minutes after admission, and Cardiopulmonary Resuscitation (CPR) was immediately begun. Massive PE was considered the most likely diagnosis in the light of her history, physical examined, and bedside ultrasonography findings; thus, recombinant tissue Plasminogen Activator (r-tPA) was administered during CPR. The second CPR attempt achieved return of spontaneous circulation within 5 minutes. She was treated at intensive care unit for 32 days and discharged from the hospital with complete recovery.

Thrombolysis after cardiopulmonary resuscitation in myocardial infarction with abdominal pain as the first presentation: A case report

RATIONALE

Thrombolysis after cardiopulmonary resuscitation in patients with acute ST-segment elevation myocardial infarction (STEMI) is controversial. This case report describes a successful thrombolysis after resuscitation in delayed-diagnosis STEMI.

PATIENT CONCERNS

A 58-year-old man presented with acute abdominal pain as the first symptom of a subsequent STEMI diagnosis. When he returned to the clinic after having been assisted with abdominal pain relief, he suffered a sudden cardiac arrest. Cardiopulmonary resuscitation was performed immediately, and thrombolysis was carried out for his anterior STEMI. He was successfully resuscitated in a short period of time.

DIAGNOSIS

The patient was diagnosed with acute and extensive anterior STEMI. The D-dimer level was normal, and pericardial effusion was ruled out.

INTERVENTIONS

After successful resuscitation, the patient received half-dose alteplase thrombolytic therapy. After a few days, the patient was transferred to a general ward. Coronary angiography revealed unobstructed flow in the left anterior descending artery.

OUTCOMES

The ST segment of the patient gradually declined after thrombolytic therapy, and the myocardial injury marker levels increased. A small amount of pleural fluid in the lungs and pulmonary infection were observed. With effective diuretic, anti-infective, and other treatments, the patient's condition gradually improved, the ventilator was removed, and vasoactive drugs were successfully discontinued. Coronary angiography revealed that the flow of the culprit artery was unobstructed, and a drug-coated balloon was implanted. No wall motion abnormalities were detected on echocardiography, and the patient recovered well.

CONCLUSIONS

In patients with abdominal pain as the first presentation, a simple initial electrocardiogram may help reduce the risk of missed STEMI diagnosis. Thrombolysis after successful resuscitation is an effective treatment for these patients. However, the effects of thrombolysis after resuscitation remain unclear. The point of dispute lies in the effectiveness and safety of thrombolysis (primarily for bleeding). Prompt thrombolysis would lead to a better prognosis if spontaneous circulation can be restored within 10 minutes.

Return of spontaneous circulation in patients with out-of-hospital cardiac arrest caused by pulmonary embolism using early point-of-care ultrasound and timely thrombolytic agent application: Two case reports

Introduction:

Acute pulmonary embolism is a confirmed cause of up to 5% of out-of-hospital cardiac arrest and 5%–13% of unexplained cardiac arrest in patients. However, the true incidence may be much higher, as pulmonary embolism is often clinically underdiagnosed. Thrombolytic therapy is a recognized therapy for pulmonary embolism–associated cardiac arrest but is not routinely recommended during cardiopulmonary resuscitation. Therefore, clinicians should attempt to identify patients with suspected pulmonary embolism. Many point-of care ultrasound protocols suggest diagnosis of pulmonary embolism for cardiac arrest patients.

Case presentation:

We describe two male patients (60 years and 66 years, respectively) who presented to the emergency department with cardiac arrest within a period of 1 week. With administration of point-of care ultrasound during the ongoing cardiopulmonary resuscitation in both patients, fibrinolytic therapy was initiated under suspicion of cardiac arrest caused by pulmonary embolism. Both patients had return of spontaneous circulation; however, only the second patient, who received fibrinolytic therapy relatively early, was discharged with a good outcome. In this report, we discussed how to diagnose and manage patients with cardiac arrest–associated pulmonary embolism with the help of point-of care ultrasound. We also discuss the different clinical outcomes of the two patients based on the experience of the clinicians and the timing of thrombolytic agent application.

Conclusions:

If acute pulmonary embolism is suspected in patients with out-of-hospital cardiac arrest, we recommend prompt point-of care ultrasound examination. Point-of care ultrasound may help identify patients with pulmonary embolism during cardiopulmonary resuscitation, leading to immediate treatment, although the clinical outcomes may vary.

Thrombolysis as a Therapeutic Modality in Cardiac Arrest

Introduction

In recent years, thrombolysis has emerged as a potentially promising treatment for cardiac arrest. Patients with cardiac arrests from myocardial infarction or pulmonary embolism, as well as out-of-hospital cardiac arrests, were reported to have improvement in both survival and neurologic outcome after being treated with thrombolysis. This paper aims to review the available literature on the use of thrombolysis in cardiac arrest.

Method

Study of papers from PubMed literature search for all articles with terms related to thrombolysis and cardiac arrest in title or abstract.

Results

Thrombolytics are thought to act by lysing both macroscopic clots and microthrombi, particularly in the cerebral microcirculation, thus alleviating or reversing post-arrest cerebral no-reflow. Their use in cardiac arrest has been restrained by concerns over their safety after cardiopulmonary resuscitation, in particular bleeding-related complications, although these concerns seem to have been misplaced.

Conclusions

Thrombolysis for cardiac arrest is likely to be most efficacious in a pre-hospital environment, and future research should be directed to this setting.

Coagulofibrinolytic Changes in Patients with Post-cardiac Arrest Syndrome

Whole-body ischemia and reperfusion due to cardiac arrest and subsequent return of spontaneous circulation constitute post-cardiac arrest syndrome (PCAS), which consists of four syndromes including systemic ischemia/reperfusion responses and post-cardiac arrest brain injury. The major pathophysiologies underlying systemic ischemia/reperfusion responses are systemic inflammatory response syndrome and increased coagulation, leading to disseminated intravascular coagulation (DIC), which clinically manifests as obstruction of microcirculation and multiple organ dysfunction. In particular, thrombotic occlusion in the brain due to DIC, referred to as the "no-reflow phenomenon," may be deeply involved in post-cardiac arrest brain injury, which is the leading cause of mortality in patients with PCAS. Coagulofibrinolytic changes in patients with PCAS are characterized by tissue factor-dependent coagulation, which is accelerated by impaired anticoagulant mechanisms, including antithrombin, protein C, thrombomodulin, and tissue factor pathway inhibitor. Damage-associated molecular patterns (DAMPs) accelerate not only tissue factor-dependent coagulation but also the factor XII- and factor XI-dependent activation of coagulation. Inflammatory cytokines are also involved in these changes via the expression of tissue factor on endothelial cells and monocytes, the inhibition of anticoagulant systems, and the release of neutrophil elastase from neutrophils activated by inflammatory cytokines. Hyperfibrinolysis in the early phase of PCAS is followed by inadequate endogenous fibrinolysis and fibrinolytic shutdown by plasminogen activator inhibitor-1. Moreover, cell-free DNA, which is also a DAMP, plays a pivotal role in the inhibition of fibrinolysis. DIC diagnosis criteria or fibrinolysis markers, including d-dimer and fibrin/fibrinogen degradation products, which are commonly tested in patients and easily accessible, can be used to predict the mortality or neurological outcome of PCAS patients with high accuracy. A number of studies have explored therapy for this unique pathophysiology since the first report on "no-reflow phenomenon" was published roughly 50 years ago. However, the optimum therapeutic strategy focusing on the coagulofibrinolytic changes in cardiac arrest or PCAS patients has not yet been established. The elucidation of more precise pathomechanisms of coagulofibrinolytic changes in PCAS may aid in the development of novel therapeutic targets, leading to an improvement in the outcomes of PCAS patients.

Double Bolus Thrombolysis for Suspected Massive Pulmonary Embolism during Cardiac Arrest

More than 70% of cardiac arrest cases are caused by acute myocardial infarction (AMI) or pulmonary embolism (PE). Although thrombolytic therapy is a recognised therapy for both AMI and PE, its indiscriminate use is not routinely recommended during cardiopulmonary resuscitation (CPR). We present a case describing the successful use of double dose thrombolysis during cardiac arrest caused by pulmonary embolism. Notwithstanding the relative lack of high-level evidence, this case suggests a scenario in which recombinant tissue Plasminogen Activator (rtPA) may be beneficial in cardiac arrest. In addition to the strong clinical suspicion of pulmonary embolism as the causative agent of the patient's cardiac arrest, the extremely low end-tidal CO2 suggested a massive PE. The absence of dilatation of the right heart on subxiphoid ultrasound argued against the diagnosis of PE, but not conclusively so. In the context of the circulatory collapse induced by cardiac arrest, this aspect was relegated in terms of importance. The second dose of rtPA utilised in this case resulted in return of spontaneous circulation (ROSC) and did not result in haemorrhage or an adverse effect.

Successful thrombolytic therapy of post-operative massive pulmonary embolism after ultralong cardiopulmonary resuscitation: a case report and review of literature

BACKGROUND AND AIMS

Cardiac arrest caused by massive pulmonary embolism (PE) is highly refractory to conventional resuscitation. Thrombolytic therapy has been considered to be an effective way to massive PE.

METHODS

We reported a case of successful thrombolytic therapy of post-operative massive PE after 90-min cardiopulmonary resuscitation (CPR) and reviewed the relevant literature.

RESULTS

We presented the case of a 48-year-old woman with surgery of varicosis of great saphenous vein who suffered from a massive PE with circulatory arrest refractory to 90 min of aggressive CPR. Thrombolysis was given only as a single dose of 50 mg of recombinant tissue plasminogen activator. Rapid haemodynamic and clinical improvement followed the bolus dose. The patient was discharged later without neurological or other sequelae. An extensive literature search of the PubMed database only identified 11 cases of massive PE with cardiac arrest during the perioperative period with a survival rate was 88.9%. The time period of CPR before thrombolysis or anti-coagulation was 15-90 min.

CONCLUSIONS

Thrombolytic therapy is useful to achieve the return of spontaneous circulation in the resuscitation of patients with cardiac arrest secondary to massive PE during the perioperative period, even in the prolong resuscitation.

Successful alteplase bolus administration for a presumed massive pulmonary embolism during cardiopulmonary resuscitation

OBJECTIVE

To describe the case of a patient successfully resuscitated with bolus alteplase for a presumed massive pulmonary embolism (PE) with associated cardiac arrest.

CASE SUMMARY

A 54-year-old man presented to the emergency department for evaluation of syncope following recent open reduction and internal fixation of his ankle. On arrival, his condition rapidly deteriorated and progressed to cardiopulmonary arrest. Because of noncompliance with postoperative thromboprophylaxis, there was high suspicion for PE. Following 40 minutes of advanced cardiac life support, empirical alteplase 50 mg was administered intravenously over 2 minutes with return of spontaneous circulation (ROSC) observed 6 minutes later. The diagnosis of PE using computed tomographic angiography was confirmed after fibrinolytic therapy. Although his hospital course was complicated by a gastrointestinal bleed requiring transfusion, he was discharged neurologically intact.

DISCUSSION

Clinical guidelines recommend fibrinolytic therapy for patients with PE and cardiac arrest. Data from retrospective analyses, case series, and case reports suggest that various fibrinolytic regimens may facilitate ROSC and improve neurologically intact survival without an increased risk of fatal hemorrhage.

CONCLUSION

The choice of fibrinolytic therapy should be based on hospital availability, with prompt initiation of treatment and incorporation of an intravenous bolus. A reasonable treatment regimen is alteplase 0.6 mg/kg (maximum of 50 mg) or fixed dose of alteplase 50 mg given over 2 to 15 minutes. Resuscitation should be continued for at least 30 minutes, or until ROSC, after fibrinolytic initiation to allow time for the medication to work.

Expanding the role of percutaneous coronary intervention in patients resuscitated from cardiac arrest

Special attention to post-cardiac arrest management is important to long-term survival and favorable neurological outcome in patients resuscitated from cardiac arrest. The use of emergent percutaneous coronary intervention in resuscitated patients presenting with ST-segment elevation myocardial infarction has long been considered an appropriate approach for coronary revascularization. Recent evidence suggests that other subsets of patients, namely, post-cardiac arrest patients without ST-segment elevation myocardial infarction, may benefit from immediate percutaneous coronary intervention following resuscitation. These findings could eventually have important implications for the care of resuscitated patients, including transportation of resuscitated patients to appropriate cardiac interventional facilities, access to treatment modalities such as therapeutic hypothermia, and coordinated care with cardiac catheterization laboratories.

Current pharmacological advances in the treatment of cardiac arrest

Cardiac arrest is defined as the sudden cessation of spontaneous ventilation and circulation. Within 15 seconds of cardiac arrest, the patient loses consciousness, electroencephalogram becomes flat after 30 seconds, pupils dilate fully after 60 seconds, and cerebral damage takes place within 90–300 seconds. It is essential to act immediately as irreversible damage can occur in a short time. Cardiopulmonary resuscitation (CPR) is an attempt to restore spontaneous circulation through a broad range of interventions which are early defibrillation, high-quality and uninterrupted chest compressions, advanced airway interventions, and pharmacological interventions. Drugs should be considered only after initial shocks have been delivered (when indicated) and chest compressions and ventilation have been started. During cardiopulmonary resuscitation, no specific drug therapy has been shown to improve survival to hospital discharge after cardiac arrest, and only few drugs have a proven benefit for short-term survival. This paper reviews current pharmacological treatment of cardiac arrest. There are three groups of drugs relevant to the management of cardiac arrest: vasopressors, antiarrhythmics, and other drugs such as sodium bicarbonate, calcium, magnesium, atropine, fibrinolytic drugs, and corticosteroids.

Successful thrombolytic therapy with recombinant tissue-type plasminogen activator for massive pulmonary embolism -A case report-

Massive pulmonary embolism is associated with significant perioperative morbidity and mortality. We report here on a case of a 69-year-old man who suffered a massive pulmonary embolism with pulseless electrical activity during knee arthroscopic surgery. After a diagnosis was made by performing transthoracic echocardiography, the patient was treated with recombinant tissue-type plasminogen activator. The patient was transferred to the intensive care unit after his hemodynamic status improved. The patient went on to make a full cardiopulmonary recovery without any complications.

Thrombolysis during resuscitation for out-of-hospital cardiac arrest

BACKGROUND

Approximately 70% of persons who have an out-of-hospital cardiac arrest have underlying acute myocardial infarction or pulmonary embolism. Therefore, thrombolysis during cardiopulmonary resuscitation may improve survival.

METHODS

In a double-blind, multicenter trial, we randomly assigned adult patients with witnessed out-of-hospital cardiac arrest to receive tenecteplase or placebo during cardiopulmonary resuscitation. Adjunctive heparin or aspirin was not used. The primary end point was 30-day survival; the secondary end points were hospital admission, return of spontaneous circulation, 24-hour survival, survival to hospital discharge, and neurologic outcome.

RESULTS

After blinded review of data from the first 443 patients, the data and safety monitoring board recommended discontinuation of enrollment of asystolic patients because of low survival, and the protocol was amended. Subsequently, the trial was terminated prematurely for futility after enrolling a total of 1050 patients. Tenecteplase was administered to 525 patients and placebo to 525 patients; the two treatment groups had similar clinical profiles. We did not detect any significant differences between tenecteplase and placebo in the primary end point of 30-day survival (14.7% vs. 17.0%; P=0.36; relative risk, 0.87; 95% confidence interval, 0.65 to 1.15) or in the secondary end points of hospital admission (53.5% vs. 55.0%, P=0.67), return of spontaneous circulation (55.0% vs. 54.6%, P=0.96), 24-hour survival (30.6% vs. 33.3%, P=0.39), survival to hospital discharge (15.1% vs. 17.5%, P=0.33), or neurologic outcome (P=0.69). There were more intracranial hemorrhages in the tenecteplase group.

CONCLUSIONS

When tenecteplase was used without adjunctive antithrombotic therapy during advanced life support for out-of-hospital cardiac arrest, we did not detect an improvement in outcome, in comparison with placebo. (ClinicalTrials.gov number, NCT00157261.)

Out-of-hospital thrombolysis during cardiopulmonary resuscitation in patients with high likelihood of ST-elevation myocardial infarction

Up to 90% of cardiac arrests are due to acute myocardial infarction or severe myocardial ischaemia. Thrombolysis is an effective treatment for ST-elevation myocardial infarction (STEMI), but there is no evidence or guideline to put forward a thrombolysis strategy during cardiopulmonary resuscitation (CPR). In two physician-manned emergency medical service (EMS) units in Berlin, Germany, using thrombolysis is based on an individual judgment of the EMS physician managing the CPR attempt. In this retrospective analysis over 3 years (total 22.164 scene calls), thrombolysis was started at the scene in 50 patients during brief intermittent phases of spontaneous circulation, and in 3 patients during ongoing CPR. On-scene diagnosis of myocardial infarction was established in 45 patients (85%) by a 12-lead ECG, 5 (9%) patients had a left bundle branch block. Sixteen patients (30%) died at the scene, 37 patients (70%) were admitted to a hospital. In-hospital mortality was 35% (13 of 37 patients), with cause of death being cardiogenic shock in nine patients, hypoxic cerebral coma in two and acute haemorrhage in two other patients. All 24 of 53 (45%) survivors were discharged with an excellent neurological recovery. CPR was started by an EMS physician in 18 of the 24 survivals (75%) and emergency medical technicians who arrived first in six (25%). Duration of CPR until return of spontaneous circulation was <10 min in 13 of 24 (54%) of the survivors. Thrombolysis was initiated during intermittent phases of spontaneous circulation in 50 (94%) of all patients and in 23 (96%) of the 24 survivors. In conclusion, this retrospective analysis shows excellent survival rates and neurological outcome in selected patients with a high likelihood of myocardial infarction, who develop cardiac arrest and are treated with thrombolysis.

[Application of the current resuscitation guidelines 2005. Case report of successful cardiopulmonary resuscitation]

The international guidelines for cardiopulmonary resuscitation are subject to continuous modification and were revised in November 2005. This report describes a case of an out-of-hospital cardiopulmonary resuscitation where the patient survived a cardiac arrest without neurological sequelae after chest compression (30:2), bag-mask ventilation and multiple biphasic defibrillation (single shocks). This article gives a practical review of the most important new recommendations in the current resuscitation guidelines. The accomplished measures are discussed on the background of the new recommendations.

A serious complication of thrombolysis after prolonged cardiac arrest: airway obstruction from tongue injury

Prolonged cardiac arrest with external chest compression was regarded as a contraindication to thrombolysis for acute myocardial infarction, although recent work has largely refuted previous concerns. This paper presents a serious haemorrhagic complication, which risked airway patency due to unrecognised nasopharyngeal airway-induced trauma and tongue biting. The patient required blood transfusion, and owing to the haemorrhage was unable to have rescue angioplasty. Methods of revascularisation after prolonged cardiac arrest are discussed.

Role of thrombolytic agents in cardiac arrest

The prognosis of patients having a cardiac arrest is generally poor, with a few exceptions. Interventions that aim to improve outcome in cardiac arrest have proved to be disappointing. In particular, no drug has been reliably proved to increase survival to discharge after cardiac arrest. Given that coronary thrombosis in situ and pulmonary thromboembolism are implicated in a large proportion of patients with cardiac arrest, the use of thrombolytic agents has been suggested. Case reports and animal studies have shown favourable results, and have proposed plausible mechanisms to explain them. This is a review of the current literature focusing on the use of thrombolysis during cardiac arrest. A comprehensive literature search was carried out on Medline from 1966 to January 2006, Embase from 1988 to January 2006 and the Cochrane Library, using the Ovid interface. Six articles were selected for review. Although some results are encouraging, all the studies currently available are limited by size and flaws in design.

Pharmacotherapy considerations in advanced cardiac life support

Cardiac arrest and sudden cardiac death remain major causes of mortality. Early intervention has been facilitated by emergency medical response systems and the development of training programs in basic life support and advanced cardiac life support (ACLS). Despite the implementation of these programs, the likelihood of a meaningful outcome in many life-threatening situations remains poor. Pharmacotherapy plays a role in the management of patients with cardiac arrest, with new guidelines for ACLS available in 2005 providing recommendations for the role of specific drug therapies. Epinephrine continues as a recommended means to facilitate defibrillation in patients with pulseless ventricular tachycardia or ventricular fibrillation; vasopressin is an alternative. Amiodarone is the primary antiarrhythmic drug that has been shown to be effective for facilitation of defibrillation in patients with pulseless ventricular tachycardia or fibrillation and is also used for the management of atrial fibrillation and hemodynamically stable ventricular tachycardia. Epinephrine and atropine are the primary agents used for the management of asystole and pulseless electrical activity. Treatment of electrolyte abnormalities, severe hypotension, pulmonary embolism, acute ischemic stroke, and toxicologic emergencies are important components of ACLS management. Selection of the appropriate drug, dose, and timing and route of administration are among the many challenges faced in this setting. Pharmacists who are properly educated and trained regarding the use of pharmacotherapy for patients requiring ACLS can help maximize the likelihood of positive patient outcomes.

Empiric tenecteplase is associated with increased return of spontaneous circulation and short term survival in cardiac arrest patients unresponsive to standard interventions

BACKGROUND

Prospective and retrospective studies have shown that empiric use of fibrinolytic agents in sudden cardiac arrest is safe and may improve outcomes in sudden cardiac arrest. Use of fibrinolytic agents for this indication is increasing in response to these data.

METHODS

A prospective multicenter observational trial was performed in three emergency departments (EDs) to determine the proportion of patients that respond to empiric fibrinolysis with tenecteplase (TNK) after failing to respond to Advanced Cardiac Life Support (ACLS) measures. Cardiac arrest patients unresponsive to ACLS, who were given TNK by their treating physician, were enrolled in an outcome registry. Return of spontaneous circulation (ROSC), survival, complications, and neurological outcomes were recorded.

RESULTS

Fifty patients received TNK after a mean of 30min of cardiac arrest and eight doses of ACLS medications. One hundred and thirteen concurrent control patients received standard ACLS measures. ROSC occurred in 26% of TNK patients (95% confidence interval (CI) 16-40%) compared to 12.4% (95% CI 6.9-20%) among ACLS controls (p=.04); 12% (4.5-24%) of TNK patients survived to admission compared to none in the control group (p=.0007); 4% (0.5-14%) survived to 24h (p=NS); and 4% (0.5-14%) survived to hospital discharge (p=NS). All survivors had a good neurological outcome (Cerebral Performance Category (CPC) 1-2). One intracranial hemorrhage (ICH) occurred. No other significant bleeding complications were observed.

CONCLUSIONS

Empiric fibrinolysis with TNK in cardiac arrest is associated with increased ROSC and short term survival, and with survival to hospital discharge with good neurological function in patients who fail to respond to ACLS. Results may improve with earlier administration. Prospective controlled interventional trials are indicated to evaluate this promising new therapy.

Cerebral resuscitation: state of the art, experimental approaches and clinical perspectives

Neuronal injury following global cerebral ischemia continues to bea central problem of patients in the postresuscitation phase following cardiocirculatory arrest. In addition to measures focusing on rapid restoration of spontaneous circulation, the most effective treatment after cardiac arrest, as shown by large randomized trials,is the use of therapeutic mild hypothermia. Current guidelines of the International Liaison Committee on Resuscitation (ILCOR)are recommending the use of therapeutic mild hypothermia for all unconscious patients after cardiac arrest. At present there is no specific neuroprotective treatment available. Promising animal experimental data concerning the use of thrombolytic agents during cardiopulmonary resuscitation have led to a large European multicenter trial (TROICA trial) that will provide its data in 2006.

Drug treatment and thrombolytics during cardiopulmonary resuscitation

PURPOSE OF REVIEW

During cardiopulmonary resuscitation, no specific drug therapy has been shown to improve survival to hospital discharge after cardiac arrest, and only few drugs have a proven benefit for short-term survival. This article reviews recent experimental and clinical data about vasopressor, antiarrhythmic and thrombolytic agents.

RECENT FINDINGS

General use of high-dose epinephrine (>1 mg) can not be recommended, whereas it should be considered during prolonged cardiopulmonary resuscitation. No catecholamine superior to epinephrine has been identified. Arginine vasopressin has been shown to be as effective as epinephrine in patients with ventricular fibrillation and pulseless electrical activity, and may be more effective in patients presenting with asystole or as the second vasopressor (after epinephrine) in refractory cardiac arrest. Sodium bicarbonate should not be 'blindly' administered during cardiopulmonary resuscitation unless an arterial blood gas analysis can be obtained, or after prolonged unsuccessful cardiopulmonary resuscitation. Amiodarone should be preferred over lidocaine, since it may improve short-term survival. Thrombolytic therapy during cardiopulmonary resuscitation may be beneficial if a pulmonary embolism or acute myocardial infarction is suggested to be the cause of the cardiac arrest.

SUMMARY

Epinephrine still represents the first-line vasopressor during cardiopulmonary resuscitation. Arginine vasopressin may be considered in patients presenting with asystole or who are unresponsive to initial treatment with epinephrine. Amiodarone should be preferred to other antiarrythmic agents in patients with cardiac arrest. Thrombolytic therapy during cardiopulmonary resuscitation is a promising new therapeutic option, but its general use in cardiac arrest cannot be recommended until the results of a large multicentre trial become available.

Trombolisis en la parada cardíaca

Both acute myocardial infarction and pulmonary thromboembolism are responsible for a great number of cardiac arrests. Both present high rates of mortality. Thrombolysis has proved to be an effective treatment for acute myocardial infarction and pulmonary thromboembolism with shock. It would be worth considering whether thrombolysis could be effective and safe during or after cardiopulmonary resuscitation (CPR). Unfortunately, too few clinical studies presenting sufficient scientific data exist in order to respond adequately to this question. However, most studies they show that thrombolysis applied during and after CPR is a therapeutic option that is not associated with greater risk of serious hemorrhaging and could possibly have beneficial effects. On the other hand, experimental data exists which show that thrombolytics can attenuate neurological damage produced after CPR. Nevertheless, clinical trials would be necessary in order to adequately establish the effectiveness and safety of thrombolysis in patients who require CPR.

Update in the prevention and treatment of deep vein thrombosis and pulmonary embolism

PURPOSE OF REVIEW

Thromboembolic events have a major impact on outcome of surgical and medical patients. This review is focused on standards and recent advances in antithrombotic strategies for prevention and therapy of venous thromboembolism and pulmonary embolism.

RECENT FINDINGS

Alert programs improve prophylactic strategies to prevent venous thromboembolism. Evidenced-based guidelines are available on antithrombotic and thrombolytic therapy outweighing the benefits, risks, burdens and costs. Selective factor Xa and direct thrombin inhibitors are at least as effective as low-molecular-weight heparin in prevention of venous thromboembolism and treatment of pulmonary embolism, but have fewer side effects and will not need routine monitoring. In high-risk orthopaedic patients but not in general surgery patients fondaparinux is superior to low-molecular-weight heparin in the prevention of thromboembolic disease. Ximelagatran, the first oral direct thrombin inhibitor, is as effective and well tolerated as warfarin. Long-term treatment is uncertain, however, because of elevation in alanine transaminase levels. In high-risk patients with contraindication for anticoagulation, retrievable vena cava filters may be an option to prevent pulmonary embolism. Permanent cava filters do not improve long-term survival and are associated with relevant side effects. Thrombolytics should be reserved for deep venous thrombosis complicated by limb gangrene and for life threatening pulmonary embolism.

SUMMARY

There is currently sufficient information based on guidelines available on preventive and therapeutic strategies for venous thromboembolism and pulmonary embolism. Antithrombotics are the therapeutic backbone. In high-risk orthopedic surgery and venous thromboembolism the new antithrombotics fondaparinux, idraparinux and ximelagatran are superior to standard treatment. Temporary caval filters may be a therapeutic option in high-risk patients with contraindication for antithrombotics.

Effects of thrombolysis during out-of-hospital cardiopulmonary resuscitation

In this post hoc analysis, we assessed effects of thrombolysis during out-of-hospital cardiopulmonary resuscitation. The original study was designed as a double-blinded, prospective, multicenter, randomized, controlled clinical trial. In this report, 1,219 patients were randomized, but 33 patients were excluded due to missing study drug codes. Thus, 1,186 patients were analyzed based on receipt (n = 99) versus nonreceipt (n = 1,087) of thrombolysis; the primary end point was hospital admission, and the secondary end point was hospital discharge. Patients who received thrombolysis versus those who did not were significantly younger (mean +/- SD 62.7 +/- 13.3 vs 66.5 +/- 14.3 years of age, p = 0.01) and more likely to have had an acute myocardial infarction (75.3% vs 54.6%, p < 0.01) or pulmonary embolism (20.2% vs 12.0%, p = 0.03) as the suspected underlying cause for cardiac arrest. In patients who underwent thrombolysis versus those who did not, cardiac arrest was more often witnessed (86.9% vs 77.5%, p = 0.03), initial ventricular fibrillation was more likely (59.6% vs 38.0%, p < 0.01), and a short estimated interval (0 to 5 minutes) between collapse and initiation of basic life support was more likely (51.3% vs 29.2%, p < 0.01). In patients who received thrombolysis, sodium bicarbonate (45.5% vs 33.0%, p = 0.01), lidocaine (32.3% vs 18.1%, p < 0.01), and amiodarone (30.3% vs 12.2%, p < 0.01) were administered significantly more often. Hospital admission rates were significantly higher in patients who underwent thrombolysis than in patients who did not (45.5% vs 32.7%, p = 0.01), and there was a trend to higher hospital discharge rates (14.1% vs 9.5%, p = 0.14). In patients who had suspected myocardial infarction, hospital admission and discharge rates were significantly higher in patients who underwent thrombolysis than in patients who did not. In logistic regression models after adjusting for confounding variables (e.g., age, initial electrocardiographic rhythm, and initiation of basic life support), hospital admission and discharge rates did not differ significantly. In conclusion, even when being employed in patients with a potentially better chance to survive, thrombolysis in patients with cardiac arrest resulted in an increased hospital admission but not discharge rate in this post hoc analysis.

International multicentre trial protocol to assess the efficacy and safety of tenecteplase during cardiopulmonary resuscitation in patients with out-of-hospital cardiac arrest: the Thrombolysis in Cardiac Arrest (TROICA) Study

Prehospital cardiac arrest has been associated with a very poor prognosis. Acute myocardial infarction and massive pulmonary embolism are the underlying causes of out-of-hospital cardiac arrest in 50-70% of patients. Although fibrinolysis is an effective treatment strategy for both myocardial infarction and pulmonary embolism, clinical experience for this therapy performed during resuscitation has been limited owing to the anticipated risk of severe bleeding complications. The TROICA study is planned as one of the largest randomized, double-blind, placebo-controlled trials to assess the efficacy and safety of prehospital thrombolytic therapy in cardiac arrest of presumed cardiac origin. Approximately 1000 patients with cardiac arrest will be randomized at approximately 60 international study centres to receive either a weight-adjusted dose of tenecteplase or placebo after the first dose of a vasopressor. Patients can be included if they are at least 18 years, presenting with a witnessed cardiac arrest of presumed cardiac origin, and if either basic life support had started within 10 min of onset and had been performed up to 10 min or advanced life support is started within 10 min of onset of cardiac arrest. Primary endpoint of the study is the 30-day survival rate, and the coprimary endpoint is hospital admission. Secondary endpoints are the return of spontaneous circulation (ROSC), survival after 24 h, survival to hospital discharge, and neurological performance. Safety endpoints include major bleeding complications and symptomatic intracranial haemorrhage.

Massive Pulmonary Embolism: Percutaneous Mechanical Thrombectomy during Cardiopulmonary Resuscitation

Seven patients with massive pulmonary embolism (PE) causing cardiac arrest underwent percutaneous mechanical thrombectomy (PMT) with Hydrolyser and Oasis catheters during cardiopulmonary resuscitation (CPR). Three received adjunctive recombinant tissue plasminogen activator. Thrombectomy was successful in restoring pulmonary perfusion in six patients (85.7%). One patient died of cardiac arrest. Systolic pulmonary pressure decreased after thrombectomy from a median of 73 mm Hg (range, 63-90 mm Hg) to 42 mm Hg (range, 32-81 mm Hg; P < .05). There was one groin hematoma that required blood transfusion. In conclusion, massive PE causing cardiac arrest can be treated with PMT simultaneously with CPR maneuvers to rapidly revert circulatory collapse, with restoration of pulmonary circulation. Larger series are needed to validate this method.

Skeletal chest injuries secondary to cardiopulmonary resuscitation

OBJECTIVE

To review the evidence on the incidence of rib and sternal fractures after conventional closed-chest compression in the treatment of cardiac arrest in adults and children, and after active compression-decompression cardiopulmonary resuscitation (ACD-CPR).

METHODS

Medline search and additional review of the cited literature in the articles found.

RESULTS

Reports on conventional CPR in adults suggest an incidence of rib fractures ranging from 13 to 97%, and of sternal fractures from 1 to 43%. Reports on CPR in children suggest an incidence of rib fractures of 0-2%, and no sternal fractures. ACD-CPR has been reported as causing rib fractures in 4-87%, and sternal fractures in 0-93% of cases.

CONCLUSIONS

Sound methodological studies on thoracic fractures due to chest compression do not exist and the available studies cannot be compared one with another. In infants and toddlers, manual CPR rarely causes skeletal chest injuries. In adults, sternal fractures occur in at least one-fifth and rib fractures as well as rib and/or sternal fractures in at least one-third of the patients during conventional CPR. There is no compelling evidence to show that an increased complication rate is associated with ACD-CPR. Rib or sternal fractures are unlikely to increase mortality, as they rarely cause severe internal organ damage. Further prospective studies are desirable to assess complications by post-mortem examinations that explicitly address them. In particular, clinical evaluation of mechanical CPR devices should be accompanied by a thorough assessment of the associated complications because data specific to this modality are not available.