Frequency of complications of cardiopulmonary resuscitation after thrombolysis during acute myocardial infarction

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.

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.

Chest Compression Injuries Detected via Routine Post-arrest Care in Patients Who Survive to Admission after Out-of-hospital Cardiac Arrest

Abstract Objective. To examine injuries produced by chest compressions in out-of-hospital cardiac arrest (OHCA) patients who survive to hospital admission. Methods. A retrospective cohort study was conducted among 235 consecutive patients who were hospitalized after nontraumatic OHCA in Minnesota between January 2009 and May 2012 (117 survived to discharge; 118 died during hospitalization). Cases were eligible if the patient had received prehospital compressions from an emergency medical services (EMS) provider. One EMS provider in the area was using a mechanical compression device (LUCAS^TM) as standard equipment, so the association between injury and use of mechanical compression was also examined. Prehospital care information was abstracted from EMS run sheets, and hospital records were reviewed for injuries documented during the post-arrest hospitalization that likely resulted from compressions. Results. Injuries were identified in 31 patients (13%), the most common being rib fracture (9%) and intrathoracic hemorrhage (3%). Among those who survived to discharge, the mean length of stay was not statistically significantly different between those with injuries (13.5 days) and those without (10.8 days; p = 0.23). Crude injury prevalence was higher in those who died prior to discharge, had received compressions for >10 minutes (versus ≤10 minutes) and underwent computer tomography (CT) imaging, but did not differ by bystander compressions or use of mechanical compression. After multivariable adjustment, only compression time > 10 min and CT imaging during hospitalization were positively associated with detected injury (OR = 7.86 [95% CI = 1.7-35.9] and 6.30 [95% CI = 2.6-15.5], respectively). Conclusion. In patients who survived OHCA to admission, longer duration of compressions and use of CT during the post-arrest course were associated positively with documented compression injury. Compression-induced injuries detected via routine post-arrest care are likely to be largely insignificant in terms of length of recovery.

A systematic review and pooled analysis of CPR-associated cardiovascular and thoracic injuries

OBJECTIVE

The incidence of thoracic injuries resulting from cardiopulmonary resuscitation (CPR) is not well characterized. We describe a case in which a CPR-associated atrial rupture was identified with ultrasound and successfully managed in the intensive care unit with a bedside thoracotomy and atrial repair. We then describe a systematic review with pooled data analysis of CPR-associated cardiovascular, pulmonary, pleural, and thoracic wall injuries.

DATA SOURCES

PubMed, Scopus, EMBASE, and Web of Science were searched to identify relevant published studies. Unpublished studies were identified by searching the Australian and New Zealand Clinical Trials Registry, World Health Organization International Clinical Trials Registry Platform, Cochrane Library, ClinicalTrials.gov, Current Controlled Trials, and Google.

STUDY SELECTION

Inclusion criteria for the pooled analysis were any clinical or autopsy study in which (a) patients underwent cardiopulmonary resuscitation, (b) chest compressions were administered either manually or with the assistance of active compression-decompression devices, and (c) autopsy or dedicated imaging assessments were conducted to identify complications. Exclusion criteria for the pooled analysis were pre-clinical studies, case reports and abstracts.

DATA EXTRACTION

Nine-hundred twenty-eight potentially relevant references were identified. Twenty-seven references met inclusion criteria.

DATA SYNTHESIS

A systematic review of the literature is provided with pooled data analysis.

CONCLUSIONS

The incidence of reported CPR-associated cardiovascular and thoracic wall injuries varies widely. CPR with active compression-decompression devices has a higher reported incidence of cardiopulmonary injuries. Bedside ultrasound may be a useful adjunct to assess and risk-stratify patients to identify serious or life-threatening CPR-associated injuries.

Fate of patients with prehospital resuscitation for ST-elevation myocardial infarction and a high rate of early reperfusion therapy (results from the PREMIR [Prehospital Myocardial Infarction Registry])

Patients with acute ST-segment elevation myocardial infarction (STEMI) needing prehospital cardiopulmonary resuscitation (CPR) have a very high adverse-event rate. However, little is known about the fate of these patients and predictors of mortality in the era of early reperfusion therapy. From March 2003 through December 2004, 2,317 patients with prehospital diagnosed STEMI were enrolled in the Prehospital Myocardial Infarction Registry. One hundred ninety patients (8.2%) underwent prehospital CPR and were included in our analysis. Overall 90% of patients were treated with early reperfusion therapy, 56.3% received prehospital thrombolysis and 1/2 of these patients received early percutaneous coronary intervention after thrombolysis, 28.4% of patients were treated with primary percutaneous coronary intervention, and 5.3% received in-hospital thrombolysis. Total mortality was 40.0%. The highest mortality was seen in patients with asystole (63%) or pulseless electric activity (64%). Independent predictors of mortality were need for endotracheal intubation and older age, whereas ventricular fibrillation as initial heart rhythm was associated with survival. In conclusion, in this large registry with prehospital diagnosed STEMI, incidence of prehospital CPR was about 8%. Even with a very high rate of early reperfusion therapy, in-hospital mortality was high. Especially in elderly patients with asystole as initial heart rhythm and with need for endotracheal intubation, prognosis is poor despite aggressive reperfusion therapy.

[Managing the post-cardiac arrest syndrome. Directing Committee of the National Cardiopulmonary Resuscitation Plan (PNRCP) of the Spanish Society for Intensive Medicine, Critical Care and Coronary Units (SEMICYUC)]

Since the advent of cardiopulmonary resuscitation more than 40 years ago, we have achieved a return to spontaneous circulation in a growing proportion of patients with cardiac arrest. Nevertheless, most of these patients die in the first few days after admission to the intensive care unit (ICU), and this situation has not improved over the years. Mortality in these patients is mainly associated to brain damage. Perhaps recognizing that cardiopulmonary resuscitation does not end with the return of spontaneous circulation but rather with the return of normal brain function and total stabilization of the patient would help improve the therapeutic management of these patients in the ICU. In this sense, the term cardiocerebral resuscitation proposed by some authors might be more appropriate. The International Liaison Committee on Resuscitation recently published a consensus document on the "Post-Cardiac Arrest Syndrome" and diverse authors have proposed that post-arrest care be integrated as the fifth link in the survival chain, after early warning, early cardiopulmonary resuscitation by witnesses, early defibrillation, and early advanced life support. The therapeutic management of patients that recover spontaneous circulation after cardiopulmonary resuscitation maneuvers based on life support measures and a series of improvised actions based on "clinical judgment" might not be the best way to treat patients with post-cardiac arrest syndrome. Recent studies indicate that using goal-guided protocols to manage these patients including therapeutic measures of proven efficacy, such as inducing mild therapeutic hypothermia and early revascularization, when indicated, can improve the prognosis considerably in these patients. Given that there is no current protocol based on universally accepted evidence, the Steering Committee of the National Cardiopulmonary Resuscitation Plan of the Spanish Society of Intensive Medicine and Cardiac Units has elaborated this document after a thorough review of the literature and an online discussion involving all the members of the committee and a consensus meeting with the aim of providing a platform for the development of local protocols in different ICSs in our country to fit their own means and characteristics.

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.

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.

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.

Bolus thrombolytic infusion during prolonged refractory cardiac arrest of undiagnosed cause

Acute myocardial infarction (AMI) and pulmonary embolism (PE) account for about 70% of cardiac arrest. Although thrombolytic therapy is an effective therapy for both AMI and PE, it is not routinely recommended during cardiopulmonary resuscitation (CPR) for fear of life threatening bleeding complications. Numerous case reports and retrospective studies have suggested a beneficial effect of thrombolytics in cardiac arrest secondary to AMI and PE; however, we present a case of successful use of bolus thrombolytics during CPR in a patient with undifferentiated cardiac arrest (undiagnosed cause) after prolonged conventional resuscitation without success.

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.

Post resuscitation care: what are the therapeutic alternatives and what do we know?

A large proportion of deaths in the Western World are caused by ischaemic heart disease. Among these patients a majority die outside hospital due to sudden cardiac death. The prognosis among these patients is in general, poor. However, a significant proportion are admitted to a hospital ward alive. The proportion of patients who survive the hospital phase of an out of hospital cardiac arrest varies considerably. Several treatment strategies are applicable during the post resuscitation care phase, but the level of evidence is weak for most of them. Four treatments are recommended for selected patients based on relatively good clinical evidence: therapeutic hypothermia, beta-blockers, coronary artery bypass grafting, and an implantable cardioverter defibrillator. The patient's cerebral function might influence implementation of the latter two alternatives. There is some evidence for revascularisation treatment in patients with suspected myocardial infarction. On pathophysiological grounds, an early coronary angiogram is a reasonable alternative. Further randomised clinical trials of other post resuscitation therapies are essential.

Therapeutic Hypothermia after Cardiac Arrest

The use of IH for 24 hours in patients who remain comatose following resuscitation from out-of-hospital cardiac arrest improves outcomes. How-ever, the induction of hypothermia has several physiologic effects that need to be considered. A protocol for the rapid induction of hypothermia is described. At present, the rapid infusion of a large volume (40 mL/kg) of ice-cold crystalloid (ie, lactated Ringer's solution) would appear to be an inexpensive, safe strategy for the induction of hypothermia after cardiac arrest. Hypothermia (33 degrees C) should be maintained for 24 hours, followed by rewarming over 12 hours. Particular attention must be paid to potassium and glucose levels during hypothermia.

Thrombolysis with streptokinase during cardiopulmonary resuscitation: a single center experience and review of the literature

OBJECTIVE

To report our experience with use of thrombolysis with streptokinase during cardiopulmonary resuscitation of patients with cardiac arrest due to myocardial infarction.

DESIGN

A case series.

METHODS

Thrombolytic therapy (streptokinase) was administered during cardiopulmonary resuscitation of 4 patients with suspected myocardial infarction as the cause of cardiac arrest.

RESULTS

3 of the 4 patients survived and were discharged from the hospital without any major complications or neurological sequela.

CONCLUSION

Thrombolysis with streptokinase during cardiopulmonary resuscitation of patients with suspected acute myocardial infarction is associated with reduced mortality and favorable neurological outcome.

[Acute coronary syndrome in the prehospital phase]

Cardiovascular diseases are the number one cause of death in Germany. In 2002 about 70,000 people died of acute myocardial infarction (AMI) and of these 37% died before arrival at hospital which underlines the relevance of adequate prehospital care. The generic term acute coronary syndrome (ACS) was introduced because a single pathomechanism accounts for the different forms and comprises unstable angina pectoris (iAP), non-ST-elevation myocardial infarction (NSTEMI), ST-elevation myocardial infarction (STEMI) and sudden cardiac death (SCD). Characteristic features are retrosternal pain, vegetative symptoms and radiation of pain into the adjoining regions. Further differentiation can only be achieved by the 12-lead ECG, as cardiac-specific enzymes do not play a role in prehospital decisions. Prehospital delays should be avoided, history and physical examination should be brief but focused, vital parameters should be assessed and monitored. Basic treatment for ACS should comprise inhalative oxygen, nitrates, morphine, aspirin and beta-blockers. If STEMI is diagnosed, patients with symptoms <12 h should undergo fibrinolytic therapy unless there is primary percutaneous coronary intervention (PCI) available within 90 min or if contraindicated. Heparin should be given to patients with STEMI depending on the choice of fibrinolytic agent, it otherwise results in a higher risk of bleeding, but in patients with iAP or NSTEMI it reduces mortality. All patients must be accompanied by the emergency physician during transportation and should be brought to a hospital with primary PCI, especially those with complicated ACS. Treatment of complications depends largely on the type, persistence and severity.

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.

Safety of thrombolysis during cardiopulmonary resuscitation

The prognosis is generally poor for patients who experience a cardiac arrest. The most common causes of sudden cardiac arrest are massive pulmonary embolism (PE) and acute myocardial infarction (MI). While thrombolysis is a first-line treatment option in massive PE and acute MI, cardiopulmonary resuscitation (CPR) has been regarded as a relative contraindication for thrombolysis because of the anticipated bleeding risk caused by traumatic cardiocompressions. However, an increasing number of case reports and clinical studies on thrombolysis during and after CPR highlight an increased frequency of the return of spontaneous circulation and a better neurological outcome of surviving patients. These effects are mainly due to the thrombolysis of macroscopic blood clots and the amelioration of microcirculatory reperfusion. This article reviews case reports and clinical studies of thrombolysis during and shortly after CPR in order to estimate the risk of severe bleeding events caused by CPR in association with thrombolysis compared with CPR without thrombolysis. Although thrombolysis per se can cause severe and potentially fatal haemorrhage, there is no evidence that severe bleeding events occur more often when thrombolysis is combined with cardiocompressions. In addition, by far the majority of bleeding complications can be treated effectively. Thus, in many cases, the possible benefit of thrombolysis during CPR seems to outweigh the potential risks. However, there may be a publication bias in some case reports and studies towards reporting successful rather than unsuccessful CPRs. In addition, not enough controlled clinical trials have yet been conducted. Therefore, data from large randomised, multicentre studies are needed to definitely answer the question of the relationship between safety and efficacy of this promising treatment option. We conclude that the currently available data do not indicate that thrombolysis contributes to a significant increase in bleeding complications when administered during CPR.

Major bleeding complications in cardiopulmonary resuscitation: the place of thrombolytic therapy in cardiac arrest due to massive pulmonary embolism

OBJECTIVE

Thrombolytic therapy in patients with massive pulmonary embolism (MPE) and prolonged cardiopulmonary resuscitation (CPR) is subject to debate. This study was performed to determine whether (1) thrombolytic treatment increases the risk of bleeding complications, (2) if the risk of bleeding is influenced by the duration of CPR and if (3) thrombolytic therapy improves outcome.

DESIGN

Retrospective cohort study.

SETTING

Emergency department of a tertiary care university hospital.

PATIENTS AND METHODS

Sixty-six patients with cardiac arrest (CA) due to MPE admitted between July 1993 and December 2001. Thirty-six patients received thrombolysis (TL) and were compared with 30 patients without thrombolytic therapy. Bleeding complications were assessed by clinical evidence or autopsy.

RESULTS

Major bleeding complications appear to occur more frequently in patients treated with thrombolytics (9/36 (25%) vs. 3/30 (10%)) even though the difference was statistically not significant (P=0.15). It appears that CPR duration >10 min has no adverse impact on major bleeding complications. No difference in the rate of major bleeding complications between thrombolyzed patients who had a CPR duration of </=10 or >10 min could be observed (2/8 (25%) vs. 7/28 (25%), P=0.99). In thrombolyzed patients a return of spontaneous circulation could be achieved more frequently (24/36 (67%) vs.13/30 (43%) in controls, P=0.06) and survival after 24 h was higher (19/36 (53%) vs. 7/30 (23%), P=0.01). Survival to discharge was also higher in the TL group (7/36 (19%) vs. 2/30 (7%)), but not statistically significant (P=0.15).

CONCLUSION

Although severe bleeding complications tend to occur more frequently in patients undergoing TL, the benefit of this treatment might outweigh the risk of bleeding.

Major bleeding complications after cardiopulmonary resuscitation: impact of thrombolytic treatment

OBJECTIVE

The risk of bleeding complications caused by thrombolysis in patients with cardiac arrest and prolonged cardiopulmonary resuscitation is unclear. We evaluate the complication rate of systemic thrombolysis in patients with out-of-hospital cardiac arrest caused by acute myocardial infarction, especially in relation to duration of cardiopulmonary resuscitation.

DESIGN

The study was designed as retrospective cohort study, the risk factor being systemic thrombolysis and the end-point major haemorrhage, defined as life-threatening and/or need for transfusion. Over 10.5 years, emergency cardiac care data, therapy, major haemorrhage and outcome of 265 patients with acute myocardial infarction admitted to an emergency department after successful cardiopulmonary resuscitation were registered.

RESULTS

We observed major haemorrhage in 13 of 132 patients who received thrombolysis (10%, 95% confidence interval 5-15%), five of these survived to discharge, none died because of this complication. Major haemorrhage occurred in seven of 133 patients in whom no thrombolytic treatment had been given (5%, 95% confidence interval 1-9%), two of these survived to discharge. Taking into account baseline imbalances between the groups, the risk of bleeding was slightly increased if thrombolytics were used (odds ratio 2.5, 95% confidence interval 0.9-7.4) but this was not significant (P = 0.09). There was no clear association between duration of resuscitation and bleeding complications (z for trend = 1.52, P = 0.12). Survival was not significantly better in patients receiving thrombolysis (odds ratio 1.6, 0.9-3.0, P = 0.12).

CONCLUSIONS

Bleeding complications after cardiopulmonary resuscitation are frequent, particularly in patients with thrombolytic treatment, but do not appear to be related to the duration of resuscitation. In the light of possible benefits on outcome, thrombolytic treatment should not be withheld in carefully selected patients.

Major pulmonary embolism: review of a pathophysiologic approach to the golden hour of hemodynamically significant pulmonary embolism

Major pulmonary embolism (PE) results whenever the combination of embolism size and underlying cardiopulmonary status interact to produce hemodynamic instability. Physical findings and standard data crudely estimate the severity of the embolic event in patients without prior cardiopulmonary disease (CPD) but are unreliable indicators in patients with prior CPD. In either case, the presence of shock defines a threefold to sevenfold increase in mortality, with a majority of deaths occurring within 1 h of presentation. A rapid integration of historical information and physical findings with readily available laboratory data and a structured physiologic approach to diagnosis and resuscitation are necessary for optimal therapeutics in this "golden hour." Echocardiography is ideal because it is transportable, and is capable of differentiating shock states and recognizing the characteristic features of PE. Spiral CT scanning is evolving to replace angiography as a confirmatory study in this population. Thrombolytic therapy is acknowledged as the treatment of choice, with embolectomy reserved for those in whom thrombolysis is contraindicated.

Thrombolytic therapy after cardiac arrest and its effect on neurological outcome

OBJECTIVE

the aim of the study is to investigate the effect of thrombolytic therapy on neurological outcome in patients after cardiac arrest due to acute myocardial infarction. Laboratory investigations have demonstrated that thrombolytic therapy after cardiopulmonary resuscitation improves neurological function.

METHODS

from July 1991 to June 1996, patients with witnessed ventricular fibrillation cardiac arrest due to acute MI and successful restoration of spontaneous circulation admitted to the emergency department were analyzed retrospectively. A logistic regression model was used to assess the association between thrombolytic therapy and neurological outcome [best cerebral performance category (CPC) within 6 months after cardiac arrest].

RESULTS

all 157 patients [median age 57 years (IQR 50-69)] were analyzed. Thrombolytic therapy was applied in 42 patients (27%). With thrombolytic therapy good functional neurological recovery (CPC 1 or 2) was achieved more frequently (69 vs. 50%, P=0.03). After controlling for age, prehospital dosage of epinephrine, and the duration of cardiac arrest we found a non significant trend towards good neurological recovery when thrombolytic therapy was given (OR 1.9, 95% CI 0.8-4.6).

CONCLUSION

thrombolytic therapy after cardiac arrest due to acute myocardial infarction is associated with improved neurological outcome.

Thrombolysis during cardiopulmonary resuscitation in fulminant pulmonary embolism: a review

OBJECTIVE

To review current knowledge on thrombolysis in patients with fulminant pulmonary embolism (FPE) who need cardiopulmonary resuscitation (CPR).

DATA SOURCES

The bibliography for the study was compiled through a search of different databases between 1966 and 2000. References cited in the articles selected were also reviewed.

STUDY SELECTION

The selection criteria included all reports published on thrombolysis, pulmonary embolism, and CPR, from case reports and case series to controlled studies.

DATA SYNTHESIS

Very few studies evaluated thrombolysis in cases of FPE that required CPR and most of these were clinical case reports and case series with a low level of scientific evidence. There has been no clinical trial to address this issue.

CONCLUSIONS

FPE can frequently produce cardiac arrest, which has an extremely high mortality despite application of the usual CPR measures. The administration of thrombolytic therapy during CPR could help to reduce the mortality, although it has classically been contraindicated. There are no published clinical trials or other high-grade studies that evaluated the efficacy and safety of this approach. From the few existing studies, it can be inferred that thrombolysis may be efficacious and safe for patients with FPE who need CPR. However, a clinical trial is required to provide evidence of value for sound clinical decision-making.

Out-of-hospital thrombolytic therapy during cardiopulmonary resuscitation in refractory cardiac arrest due to acute myocardial infarction

Out-of-hospital thrombolytic therapy was administrated to a 53-year-old woman with confirmed acute myocardial infarction and refractory cardiac arrest. Standard advanced cardiac life support measures were performed by an out-of-hospital critical care team but they were unsuccessful. Thrombolytic therapy was given as a rescue therapy after prolonged cardiopulmonary resuscitation. The patient recovered a sinus rhythm and circulation 20 minutes after a bolus infusion of tissue plasminogen activator and was fit to be transported to the hospital. Reversal of arterial occlusion was confirmed at the hospital. There was no sequelae related to thrombolytic therapy and the patient was finally discharged 21 days later. This is the first published report of out-of-hospital thrombolytic therapy during cardiopulmonary resuscitation for a patient with refractory cardiac arrest due to acute myocardial infarction.

Recombinant tissue plasminogen activator during cardiopulmonary resuscitation in 108 patients with out-of-hospital cardiac arrest

BACKGROUND

Thrombolytic therapy during cardiopulmonary resuscitation (CPR) is a controversial issue in emergency medicine practice. This study was conducted to determine whether administration of recombinant tissue plasminogen activator (rt-PA) in out-of-hospital cardiac arrest of non-traumatic aetiology improves CPR outcome.

METHODS AND RESULTS

A retrospective chart review of 401 patients with out-of-hospital cardiac arrest who were resuscitated by the emergency medical services (EMS) during a 6 year period was performed. A total of 108 patients received rt-PA during CPR and were compared to 216 controls, closely matched according to baseline characteristics, arrival status and ECG findings. Administration of rt-PA was optional. Return of spontaneous circulation (ROSC) occurred in 76 patients under rt-PA treatment (70.4 vs. 51.0% in controls; P=0.001). Fifty-two patients from the lysis group survived the first 24 h (48.1 vs. 32.9% in controls; P=0.003), while 27 (25.9%) survived to discharge. Autopsy reports revealed major bleeding complications in six patients receiving rt-PA treatment. Fulminant intracranial haemorrhage was observed in one patient who received rt-PA and in two cases from the control group.

CONCLUSIONS

Thrombolytic therapy may improve frequency of return of spontaneous circulation substantially and increase primary survival in patients with non-traumatic cardiac arrest. Serious bleeding complications are not frequently observed under rt-PA treatment.

Thrombolytic therapy during cardiopulmonary resuscitation and the role of coagulation activation after cardiac arrest

Thrombolysis is an effective causal therapy for patients suffering from massive pulmonary embolism or acute myocardial infarction. In more than 70% of patients with cardiac arrest, one of these two diseases is the underlying cause of deterioration. Nevertheless, because of the fear of severe bleeding complications, thrombolytic therapy during cardiopulmonary resuscitation (CPR) has been contraindicated. Increasing clinical experience and data from open studies now suggest that thrombolysis during CPR can contribute to hemodynamic stabilization and survival in patients with massive pulmonary embolism and acute myocardial infarction, after conventional CPR procedures have been performed unsuccessfully. After administration of thrombolytic agents, some patients have been stabilized even after more than 90 minutes of CPR. Besides the specific causal action of thrombolytic agents at the site of pulmonary emboli and coronary thrombosis, experimental data indicate that thrombolysis during CPR can improve microcirculatory reperfusion, which may be most important in the brain. In accordance with these data, marked activation of blood coagulation without adequate activation of endogenous fibrinolysis has been demonstrated during reperfusion after cardiac arrest. Massive coagulation activation with subsequent fibrin formation is responsible for microcirculatory reperfusion disorders, and thrombolytic therapy may be indicated. However, no controlled studies are available on this therapeutic concept. Because the risk of bleeding complications is potentially associated with the administration of thrombolytic agents, although this occurs far less than anticipated, thrombolysis during CPR is presently a treatment strategy that can be performed on an individual basis. Whether thrombolysis during CPR can improve survival rates and neurologic outcomes should be addressed in randomized, controlled trials.

Efficacy and safety of thrombolytic therapy after initially unsuccessful cardiopulmonary resuscitation: a prospective clinical trial

BACKGROUND

During cardiopulmonary resuscitation (CPR), thrombolysis can help to stabilise patients with pulmonary embolism and myocardial infarction. Moreover, thrombolysis during CPR has beneficial effects on cerebral reperfusion after cardiac arrest. We investigated this new therapeutic approach in patients in whom conventional CPR had been unsuccessful.

METHODS

We assessed, in a prospective study, patients undergoing CPR after out-of-hospital cardiac arrest for cardiological reasons in whom return of spontaneous circulation was not achieved within 15 min. According to the Ustein criteria, our control group consisted of patients who were assessed during 1 year. After this year patients were treated with a bolus of 5000 U of heparin and 50mg, over 2 min, of tissue-type plasminogen activator (rt-PA treated group). This intervention was repeated if return of spontaneous circulation was not achieved within the following 30 min. For controls only CPR was given.

FINDINGS

Overall, 90 patients were included; heparin and rt-PA were given to 40 patients. There were no bleeding complications related to the CPR procedures. Of the rt-PA group, 68% (27) had return of spontaneous circulation and 58% (23) were admitted to a cardiac intensive care unit, compared with 44% (22; p=0.026) and 30% (15; p=0.009) of the controls, respectively. At 24 h after cardiac arrest a larger proportion of the rt-PA group than of the controls was alive (35% [14] vs 22% [11], p=0.171), and 15% (six) of rt-PA-treated patients and 8% (four) of controls could be discharged from hospital.

INTERPRETATION

After initially unsuccessful out-of-hospital CPR, thrombolytic therapy combined with heparin is safe and might improve patient outcome. On the basis of our data a randomised controlled trial might be regarded as ethical.

Medical treatment for acute coronary syndromes

The medical treatment of acute coronary syndromes with thrombolytic, antithrombin, and antiplatelet agents is a major area of research and a vast topic for clinical review. This review summarizes important recent findings on the background of existing pathological and clinical knowledge to provide an understanding of the basis of current therapy and the new therapies that are likely to be introduced in the near future. Current controversies regarding the management of these conditions and the choice between medical, interventional, and combined strategies in different situations are also discussed.

Successful out-of-hospital cardiopulmonary resuscitation: what is the optimal in-hospital treatment strategy?

The aim of the study was to evaluate prognostic factors in patients after successful out-of-hospital resuscitation (sOHR) within 30 min after admission. A prognostic scoring scale in patients surviving OHR was analysed. We also studied the effect of these predictive factors and the in-hospital treatment (percutaneous transluminal coronary angioplasty (PTCA) vs. thrombolysis) on mortality. We performed a retrospective analysis of the emergency medical system forms and medical files of 72 consecutive patients aged > or =18 years with sOHR. Of these 72 patients 37 (51%) met the electrocardiographic and enzymatic criteria for acute myocardial infarction (AMI). Ten of the 37 AMI patients (27%) underwent acute PTCA as primary treatment and seven patients (19%) received thrombolytic therapy for AMI despite prolonged (mean 24+/-13 min) cardiopulmonary resuscitation (CPR). The remaining 20 patients had no specific infarct treatment. Despite successful PTCA, in eight out of ten patients, their mortality in hospital was 60% (6/10). Mortality in the thrombolysis group was 57% (4/7). For the remaining 20 MI-patients the mortality was 65% (13/20). Univariate and multivariate analyses were performed to design a weighted prognostic scoring system. The Glasgow coma scale (GCS) was the strongest independent predictor (r=0.76, P< or =0.001) for in-hospital death.

CONCLUSIONS

in-hospital mortality after successful OHR seems to largely depend on neurological status at admission and much less on the specific treatment of myocardial infarction. The prognostic scoring system accurately predicted the in-hospital mortality and can be used for early treatment stratification; however, it should be proven in a prospective study.

Thrombolytic therapy in acute myocardial infarction

Early reperfusion of thrombotically occluded coronary arteries by thrombolytic therapy has become a routine option in initial therapy of acute myocardial infarction. Many efforts have been made to improve the biological properties of thrombolytic agents in terms of fibrin specificity, plasma half-life and resistance to natural plasma inhibitors, to improve adjuvant therapy and to shorten the 'pain to reperfusion' time. Numerous randomised, multicentre trials have analysed the benefit of the various thrombolytic agents and regimens, which has enabled the creation of a 'current standard of therapy'. This review presents an update on available thrombolytic agents, their biochemical and pharmacological properties and results from clinical trials.

Thrombolytic eligibility

The Fibrinolytic Therapy Trialists' Collaborative Group has demonstrated that patients without clear contraindications who present with ischaemic chest pain within 12 hours of the onset of symptoms and who have ST segment elevation or bundle branch block on their electrocardiogram (ECG), will benefit from thrombolytic therapy. Therefore the treatment of patients presenting with ischaemic chest pain is guided by the initial ECG. This paper addresses the question of thrombolytic eligibility in several subsets of patients who may benefit from treatment. It also explores the data which confirm the benefit for patients presenting with an inferior myocardial infarction and for those presenting from six-12 hours after the onset of symptoms. In conclusion, thrombolytic therapy should not be routinely withheld from diabetic or elderly patients, menstruating women and patients who have had cardiopulmonary resuscitation.

Thrombolysis for acute myocardial infarction

Thrombolytic therapy has been a major advance in the management of acute myocardial infarction. Unfortunately, it continues to be underused or is administered later than is optimal. Thrombolytic therapy works by lysing infarct artery thrombi and achieving reperfusion, thereby reducing infarct size, preserving left ventricular function, and improving survival. The most effective thrombolytic regimens achieve angiographic epicardial infarct-artery patency in only approximately 50% of patients within 90 minutes. Bleeding requiring transfusion occurs in approximately 5% of patients and stroke in approximately 1.8% with these regimens, which include adjunctive aspirin and intravenous heparin. There are several ways in which reperfusion rates and thus patient outcomes might be improved, such as different dosing regimens of established agents; combinations of different agents; improved adjunctive therapy such as direct antithrombin agents, low-molecular-weight heparin, or glycoprotein IIb/IIIa receptor antagonists; or the development of novel thrombolytic agents with enhanced fibrin specificity, resistance to native inhibitors, or prolonged half-lives allowing bolus administration. All of these strategies are being tested in clinical trials. The best approach currently is to administer thrombolytic therapy as soon as possible to all patients without contraindications who present within 12 hours of symptom onset and have ST-segment elevation on the ECG or new-onset left bundle-branch block, unless an alternative reperfusion strategy is planned.

Bolus thrombolytic infusions during CPR for patients with refractory arrest rhythms: outcome of a case series

Thrombolytic therapy has been accepted in the treatment of acute myocardial infarction. Given historical recommendations that thrombolytic therapy is contraindicated in patients receiving CPR, its potential clinical benefit for facilitating conversion of rhythm in patients in refractory cardiac arrest has not been investigated. We present three case reports in which patients with confirmed acute myocardial infarction had a witnessed cardiac arrest in the ED. Standard Advanced Cardiac Life Support measures failed in all three cases. A bolus infusion of tissue plasminogen activator was administered during CPR in refractory ventricular fibrillation (two cases) and pulseless ventricular tachycardia (one case). Patients were given tissue plasminogen activator and had defibrillation, followed by a spontaneous return of circulation, with resuscitation and subsequent discharge. No postarrest sequelae were observed as a result of thrombolytic use during the resuscitative process. We conclude that bolus thrombolytic infusions during CPR may facilitate spontaneous return of circulation in select patients with confirmed acute myocardial infarction, witnessed cardiac arrest in the ED, and refractory ventricular fibrillation or tachycardia.

Unusual bleeding complications of thrombolytic therapy after cardiopulmonary resuscitation. Three case reports

The authors present three case reports retrospectively casting doubt on the benefit of thrombolysis after external cardiac massage.