Cardiac resuscitation with percutaneous cardiopulmonary support

Impact of age on extracorporeal membrane oxygenation survival of patients with cardiac failure

Purpose

Extracorporeal membrane oxygenation (ECMO) is used to treat patients in critical condition with cardiogenic shock. However, few studies have examined the effect of old age in ECMO survival. This study analyzed the impact of age on ECMO survival of patients with cardiac failure, and analyzed predictive factors for survival according to age.

Materials and methods

We retrospectively reviewed the medical records of 95 patients who required veno-arterial (V-A) ECMO between May 2009 and May 2016 at a single center. Patients were classified into “age ≥65” (n=48, 50.5%) and “age <65” (n=47, 49.5%) groups.

Results

The age ≥65 group was significantly associated with increased mortality (HR: 1.715; 95% CI =1.038–2.831) at 90 days after ECMO initiation. These associations were attenuated and did not retain statistical significance after adjustment for comorbidities (HR: 1.485; 95% CI =0.844–2.614). To determine predictive factors of mortality, multivariate logistic analysis revealed that age ≥65 (OR 5.750; 95% CI [1.508–21.920]; P=0.010), low pre-ECMO serum bicarbonate (OR 0.884; 95% CI [0.788–0.991]; P=0.035), and high pre-ECMO serum creatinine (OR 4.546; 95% CI [1.021–20.239]; P=0.047) were significantly associated with survival to 90 days. By analyzing two groups separately, high pre-ECMO serum potassium level (OR 3.552; 95% CI [1.023–12.331]; P=0.046) was the only independent predictor in patients aged <65 years while low Glasgow Coma Scale score (OR 0.698; 95% CI [0.478–1.019]; P=0.063) showed a considerable trend toward significance in patients aged ≥65.

Conclusion

Older age was not an independent risk factor for mortality at 90 days among V-A ECMO patients. In addition, our study provides understanding of the differences in predictive factors for ECMO survival according to age. Pre-ECMO laboratory findings and mental status can assist clinicians in the prediction of a patient’s prognosis.

Clinical outcomes of patients with acute myocardial infarction complicated by severe refractory cardiogenic shock assisted with percutaneous cardiopulmonary support

PURPOSE

Limited data are available on the role of percutaneous cardiopulmonary support (PCPS) for the treatment of acute myocardial infarction (AMI) patients with cardiogenic shock. We investigated the clinical outcomes and predictors of in-hospital mortality after PCPS in patients with AMI complicated by severe refractory cardiogenic shock.

MATERIALS AND METHODS

From January 2004 to December 2011, we analyzed data from 96 consecutive AMI patients with cardiogenic shock assisted by a PCPS system. The primary outcome was in-hospital mortality. The predictors of in-hospital mortality were determined by a Cox proportional-hazards model.

RESULTS

In-hospital mortality occurred in 51 (53.1%) patients and 58 (60.4%) patients were able to be weaned from PCPS. Cardiopulmonary resuscitation (CPR) was performed in 61 (63.5%) patients before PCPS initiation. On multivariate analysis, age≥67 years [adjusted hazard ratio (HR), 4.74; 95% confidence interval (CI), 2.27-9.93; p<0.001], CPR (adjusted HR, 2.32; 95% CI, 1.11-4.85; p=0.03), lactate clearance for 48 hours<70% (adjusted HR, 2.50; 95% CI, 1.04-6.05; p=0.041), and unsuccessful revascularization (adjusted HR, 3.57; 95% CI, 1.85-6.90; p=0.002) were independent predictors of in-hospital mortality after PCPS in patients with AMI complicated by cardiogenic shock.

CONCLUSION

In spite of PCPS management, AMI patients complicated by severe refractory cardiogenic shock demonstrated high mortality. Older age, CPR, lower lactate clearance for 48 hours, and unsuccessful revascularization were independent predictors of in-hospital mortality.

Extracorporeal life support for cardiogenic shock: influence of concomitant intra-aortic balloon counterpulsation

OBJECTIVES

Intra-aortic balloon counterpulsation (IABP) during extracorporeal life support (ECLS) for cardiogenic shock may improve pulsatility and coronary perfusion, thereby promoting recovery of cardiac function. However, the risks and benefits of IABP during ECLS in real clinical settings have not been evaluated. This study aims to evaluate the effect of IABP on the early outcome of ECLS for cardiogenic shock.

METHODS

We evaluated 253 adult patients (aged 58.8 ± 15.3 [mean ± standard deviation] years, 154 males) undergoing ECLS for cardiogenic shock from January 2005 to August 2012. Of them, 60 patients underwent concomitant IABP (IABP group) and 193 underwent ECLS only (control group). In-hospital outcomes were compared using the inverse probability of treatment weighting based on propensity scores.

RESULTS

The indications for ECLS were low cardiac output after cardiac surgery in 118 patients (46.6%), heart failure in 71 (28.1%), acute myocardial infarction in 49 (19.4%) and others in 15 (5.9%). Successful ECLS weaning rate was significantly higher in the IABP group than in the control group (61.7 vs 42.0%, P = 0.008); however, there was no significant difference in in-hospital mortality between the two groups (68.6 vs 72.0%, P = 0.58). After adjustment for propensity of treatment assignment conditional on baseline characteristics, the IABP group showed a decreased risk of weaning failure (odds ratio [OR] 0.51; 95% confidence interval [CI] 0.28-0.92, P = 0.024) but with a similar risk of in-hospital mortality (OR 0.85; 95% CI 0.46-1.60; P = 0.62) compared with the control group.

CONCLUSIONS

The use of IABP during ECLS increased a successful ECLS weaning rate, but was not translated into improved survival. Studies on larger populations may verify the survival effect of IABP during ECLS.

Might rapid implementation of cardiopulmonary bypass in patients who are failing to recover after a cardiac arrest potentially save lives?

The question addressed was whether it might be beneficial to have a rapid-response emergency cardiopulmonary bypass service for patients who suffer an in-hospital or an out-of-hospital cardiac arrest of any aetiology. Eighty-five papers were reviewed using the reported search, of which 15 represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The concept of using emergency cardiopulmonary bypass (ECPB) for the management of cardiogenic shock and refractory cardiac arrest was developed in the late 1990s. Since this time, a large number of centres worldwide have reported success with use of ECPB for cardiac arrest refractory to conventional resuscitation techniques and for cardiogenic shock. This is a relatively new advancement in resuscitative strategy and is expanding in clinical practice. Clinical studies and experimental data reveal that ECPB is a very effective tool in the return of spontaneous circulation following refractory cardiac arrest. Resuscitation with this technique demonstrated survival benefit when compared with patients having conventional cardiopulmonary resuscitation for >10 min after witnessed in-hospital arrest, especially if the cause of arrest is of cardiac origin. The reported finding from a systematic review of 1494 patients treated with ECPB noted that the overall survival rate was 47.4%; their results indicate that the application of ECPB in cardiac arrest improves survival and the likelihood of a satisfactory neurological outcome. An additional review revealed that acceptable survival rate and neurological outcomes (30%) can be achieved with extracorporeal cardiopulmonary resuscitation in children after prolonged cardiac arrest (up to 95 min) refractory to standard resuscitation. However, no study has provided clear-cut evidence of the merits of ECPS in patients with out-of-hospital cardiac arrest, although many case reports and case series have concluded that it is an effective method. We conclude that institution of emergency cardiopulmonary bypass may save the lives of patients in whom routine attempts at resuscitation after a cardiac arrest fail, especially after >10 min. The likelihood of success is much higher for patients who have in-hospital witnessed cardiac arrest.

Predictive factors for successful weaning from percutaneous cardiopulmonary support in patients with cardiogenic shock complicating acute myocardial infarction

BACKGROUND AND PURPOSE

Percutaneous cardiopulmonary support (PCPS) is useful in the rescue of patients who have experienced severe cardiogenic shock. We investigated the predictive factors of survival among patients with cardiogenic shock requiring PCPS.

METHODS AND SUBJECTS

We enrolled 29 patients (21 men and 8 women, 73 ± 10 years old) with circulatory collapse complicating acute myocardial infarction (AMI) requiring PCPS. Fifteen patients could be weaned from PCPS and survived for more than 1 month (group A), while the other 14 patients could not (group B). We investigated the initial PCPS settings, and performed the appropriate laboratory tests. Hemodynamic data and arterial base excess (BE) values were recorded throughout the PCPS treatment.

RESULTS

There was no difference in the laboratory test results or the left ventricular ejection fraction between the groups at the start of PCPS. PCPS flow (l/min) was significantly lower in group A than in group B at the 24th hour of PCPS (2.26 ± 0.36 and 2.54 ± 0.41, respectively). There were no differences in blood pressure between the groups. During the 24-h period prior to the end of PCPS, BE remained almost normal in group A. In group B, BE decreased continuously throughout the same period. BE values were significantly lower compared to those obtained in group A 12h prior to the end of PCPS.

CONCLUSIONS

A reduction in PCPS flow without hemodynamic collapse may allow for successful weaning from PCPS. BE may be a potent factor in determining when to terminate PCPS.

A review of the fundamental principles and evidence base in the use of extracorporeal membrane oxygenation (ECMO) in critically ill adult patients

Extracorporeal membrane oxygenation (ECMO) comprises a commonly used method of extracorporeal life support. It has proven efficacy and is an accepted modality of care for isolated respiratory or cardiopulmonary failure in neonatal and pediatric populations. In adults, there are conflicting studies regarding its benefit, but it is possible that ECMO may be beneficial in certain adult populations beyond postcardiotomy heart failure. As such, all intensivists should be familiar with the evidence-base and principles of ECMO in adult population. The purpose of this article is to review the evidence and to describe the fundamental steps in initiating, adjusting, troubleshooting, and terminating ECMO so as to familiarize the intensivist with this modality.

Efficacy of veno-arterial extracorporeal membrane oxygenation in acute myocardial infarction with cardiogenic shock

AIM

We analyzed the results of acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) necessitating extracorporeal membrane oxygenation (ECMO), and investigated for the associated risk factors for poor clinical outcomes.

METHODS

We retrospectively reviewed the medical records of 27 patients who required ECMO for AMI associated with CS between April 2006 and July 2010. Mean age was 63.7 ± 11.0 (range: 45-81) years, and there were 16 males (59.3%).

RESULTS

The mean duration of ECMO support was 30.2 ± 30.1 (range: 1-141)h. Cardiopulmonary resuscitations (CPR) were performed in 21 patients (77.8%) before ECMO initiation. Twenty-two patients (81.5%) were successfully weaned off ECMO, and 16 patients (59.3%) survived to discharge. The 30-day mortality was 37.0% (10/27 patients). Complications developed in 17 patients (63.0%: pneumonia in 10 patients, acute renal failure in 10 patients, massive bleeding in 4 patients, and thromboembolic event in 1 patient). The period between CPR initiation and ECMO commencement was a significant risk factor for ECMO weaning failure. High pre-ECMO serum lactate level was identified as a significant risk factor for poor survival on univariated and multivariated analysis.

CONCLUSION

ECMO support could improve survival in patients who suffer AMI associated with CS, and early ECMO initiation yields better outcomes (successful ECMO weaning).

Contrast media injection into right coronary artery caused thrombus extraction to aorta that may have resulted in left main trunk thrombosis

A 59-year-old man with inferior acute myocardial infarction underwent an urgent coronary angiography and as a result a total occlusion of the ostial right coronary artery (RCA) was observed. Interestingly, the thrombus in the RCA clearly shortened within 2.3 s during the contrast media injection. While we prepared for percutaneous coronary intervention (PCI) of the RCA, ventricular fibrillation occurred and pulseless electrical activity continued in spite of repeated cardioversion. Despite no stenosis in the left main trunk (LMT) in the initial coronary angiography, the LMT was totally occluded. Following aspiration therapy on the LMT with percutaneous cardiopulmonary support, PCI of the RCA was performed. A coronary angiography should be carefully performed if a lot of thrombi exist in the coronary ostium because LMT embolism may have been caused by thrombus extraction from the RCA by contrast media injection.

Potential risk of provisional stenting in left main coronary artery bifurcation in multivessel-related acute coronary syndrome

We present a case of an elderly man suffering from an acute coronary syndrome (ACS) with preshock vital signs and remarkable ST-T wave depression in leads V4-V6, and ST elevation in lead aVR. Coronary angiography showed total occlusion of the right coronary artery (RCA) and impending occlusion in the distal left main coronary artery (LMCA) with a tandem lesion in the proximal left anterior descending artery (LAD). After insertion of an intra-aortic balloon pump both the LAD and left circumflex artery (LCX) were dilated alternatively; and cross-over stenting in the LMCA bifurcation was subsequently performed. However, total occlusion of the LCX occurred and it caused acute hemodynamic collapse and ventricular fibrillation storm. Immediate installation of percutaneous cardio-pulmonary support system allowed stent deployment to be performed in the RCA and subsequent reopening of the LCX that led to a return to sinus rhythm. The patient recovered almost normal left ventricular wall motion and previous activity without any neurological deficit within 2 weeks. Provisional stenting in ACS in the LMCA bifurcation with multivessel disease has a potential risk of acute hemodynamic collapse; a planned two-stent deployment strategy may assure a higher rate of safety in such cases.

Patient selection and therapeutic strategy for emergency percutaneous cardiopulmonary system in cardiopulmonary arrest patients

BACKGROUND

To clarify the appropriate application and therapeutic strategy for the percutaneous cardiopulmonary system (PCPS) in patients in cardiopulmonary arrest (CPA), the effects of the duration of cardiopulmonary resuscitation (CPR), diagnosis of underlying diseases, subsequent intervention and complications were retrospectively investigated for the correlation between discharge or death of patients. The patients were treated under an identical therapeutic PCPS protocol.

METHODS AND RESULTS

The 69 CPA patients [55 males (78.6%), 14 females; age, 55.0 +/-15.3 years; age range 15-79 years, 50 in-hospital CPA (I-CPA) and 19 out-of-hospital CPA (O-CPA) patients] were treated with emergency PCPS. The mean duration of CPR was 43.6 +/-37.4 min. Of 18 discharged patients (26.1%), 14 had I-CPA and 4 had O-CPA. Significant factors in the discharge of patients were confirmed diagnosis, subsequent treatment and prevention of complications associated with PCPS.

CONCLUSIONS

Appropriate patient selection for PCPS in cases of O-CPA is likely to give a similar survival rate as for I-CPA. Patient selection and reversibility of the underlying disease and clinical state after starting PCPS affect the prognosis. Aggressive diagnosis and therapy for the underlying disease and prevention of complications associated with PCPS are essential factors in successful discharge of patients. Patients with an unknown etiology are not expected to fully recover, despite PCPS.

Clinical review: aggressive management and extracorporeal support for drug-induced cardiotoxicity

Poisoning may induce failure in multiple organs, leading to death. Supportive treatments and supplementation of failing organs are usually efficient. In contrast, the usefulness of cardiopulmonary bypass in drug-induced shock remains a matter of debate. The majority of deaths results from poisoning with membrane stabilising agents and calcium channel blockers. There is a need for more aggressive treatment in patients not responding to conventional treatments. The development of new antidotes is limited. In contrast, experimental studies support the hypothesis that cardiopulmonary bypass is life-saving. A review of the literature shows that cardiopulmonary bypass of the poisoned heart is feasible. The largest experience has resulted from the use of peripheral cardiopulmonary bypass. However, a literature review does not allow any conclusions regarding the efficiency and indications for this invasive method. Indeed, the majority of reports are single cases, with only one series of seven patients. Appealing results suggest that further studies are needed. Determination of prognostic factors predictive of refractoriness to conventional treatment for cardiotoxic poisonings is mandatory. These prognostic factors are specific for a toxicant or a class of toxicants. Knowledge of them will result in clarification of the indications for cardiopulmonary bypass in poisonings.

Treatment of poisoning induced cardiac impairment using cardiopulmonary bypass: a review

Severe poisoning can cause potentially fatal cardiac depression. Cardiopulmonary bypass (CPB) can support the depressed myocardium, but there are no clear indications or guidelines available on its use in severe poisoning. A review was conducted of relevant papers in the available literature (seven single case reports of both deliberate and accidental ingestion of cardiotoxic drugs and two animal studies). Although CPB is rarely used in the management of poisoning, it may have potential benefits for haemodynamic instability not responding to conventional measures. At present there is insufficient evidence concerning the use of CPB as a treatment for severe cardiac impairment due to poisoning (grade C). This review suggests that in patients with severe and potentially prolonged reversible cardiotoxicity there is potential for full survival with CPB, provided that the patient has not already sustained hypoxic cerebral damage due to resistant hypotension prior to its use.

Does veno-arterial bypass without an artificial lung improve the outcome in dogs undergoing cardiac arrest?

We hypothesized that maintaining circulation and blood pressure by veno-arterial bypass (V-A bypass) without oxygenation would improve cardiopulmonary resuscitation (CPR) and survival rates. A total of 32 dogs, divided into four groups, were subjected to normothermic ventricular fibrillation (VF) for 15 min. The method of CPR was the same in the four groups, except for the method and timing of V-A bypass. We attempted to resuscitate the dogs without V-A bypass (control), with V-A bypass not including an artificial lung during VF, with V-A bypass not including an artificial lung during CPR, and with V-A bypass including an artificial lung during CPR. CPR was continued until restoration of spontaneous circulation (ROSC) or for 30 min. Although blood pressure was well maintained, severe hypoxemia was observed during V-A bypass without an artificial lung. The resultant hypoxemia was very detrimental. ROSC was achieved more easily in all dogs in the bypass group with an artificial lung. No significant difference in survival rates was demonstrated among the four groups (P = 0.11). We concluded that V-A bypass without oxygenation does not improve the chances for CPR and outcome after cardiac arrest in dogs. Our results suggest that oxygenation is indispensable in CPR.

Oozing-type of left ventricular rupture treated under percutaneous cardiopulmonary support without surgical repair

A 65-year-old man was admitted to the National Defense Medical College Hospital for acute anterolateral myocardial infarction and cardiogenic shock. Emergency coronary angiography demonstrated occlusion of the proximal left anterior descending artery. Primary percutaneous transluminal coronary angioplasty (PTCA) was successfully performed with the support of intra-aortic balloon pumping (IABP) and medical treatment to stabilize the patient's blood pressure. On the second hospital day, the patient suffered cardiac tamponade. Pericardiocentesis showed bloody fluid and revealed that an oozing-type of left ventricular rupture had occurred after the myocardial infarction. Cardiogenic shock persisted after successful removal of the pericardial effusion. Although the heparinization required during percutaneous cardiopulmonary support (PCPS) can increase pericardial effusion, PCPS was initiated to correct the systemic hypoperfusion; a surgical team was on standby in case massive pericardial effusion resulted, but fortunately that did not occur, and cardiac function recovered. The patient was weaned successfully from PCPS and IABP and has remained in a satisfactory condition for over 1 year. PCPS contributed to the patient's recovery from cardiac shock and may have decreased the effusion from the oozing-type rupture by reducing ventricular wall tension.

Orthotopic liver transplantation in a patient with severe portopulmonary hypertension

Liver transplantation in patients with severe portopulmonary hypertension (PPH) has been associated with mortality rates in the range of 70% to 80%. Preoperative long-term epoprostenol therapy reverses pulmonary hypertension and may be a valuable possibility to reduce mortality in patients with severe PPH undergoing orthotopic liver transplantation. We want to report a patient with severe PPH, who was treated with intravenous epoprostenol for an 8-month period, after which pulmonary vascular resistance had decreased from 12 to 3 Wood units. Nevertheless, the patient developed intractable perioperative right heart failure necessitating transient mechanical circulatory support. The patient was weaned from mechanical circulatory support, but died from another episode of acute right heart failure after 28 days. Complicated liver transplantation associated with major cardiovascular stress is obviously not tolerated in patients with severe portopulmonary hypertension even after preoperative long-term epoprostenol therapy.

Long-term mild hypothermia with extracorporeal lung and heart assist improves survival from prolonged cardiac arrest in dogs

BACKGROUND AND PURPOSE

although normothermic extracorporeal lung and heart assist (ECLHA) improves cardiac outcomes, patients can not benefit from hypothermia-mediated brain protection. The present study evaluated the effects of long-term ECLHA with mild to moderate hypothermia (33 degrees C) in a canine model of prolonged cardiac arrest.

METHODS

15 dogs were assigned to either the hypothermic (seven dogs, 33 degrees C) or normothermic group (eight dogs, 37.5 degrees C). All dogs were induced to normothermic ventricular fibrillation (VF) for 15 min, followed by 24 h of ECLHA and 72 h of intensive care. The hypothermia group maintained core (pulmonary artery) temperature at 33 degrees C for 20 h starting from resuscitation, then were rewarmed by 28 h. Outcome evaluations included: (1) mortality; (2) catecholamine dose; (3) time to extubation; (4) necrotic myocardial mass (g); and (5) neurological deficits score (NDS).

RESULTS

in the normothermic group five dogs died of cardiogenic shock and one dog succumbed to poor oxygenation. The two surviving dogs remained comatose (NDS 60.5 +/- 4.9%) with necrotic myocardial mass of 14.5 +/- 3.5 g. In the hypothermic group, one dog died from pulmonary dysfunction, the other six dogs survived. The surviving dogs showed brain damage (29.8 +/- 2.5%), but there was evidence of some brain-protective effect. The mass of necrotic myocardium was 4.2 +/- 1.3 g in the hypothermic group or 3.4 times smaller than in the normothermic group. The survival rate was significantly higher in the hypothermic than in the normothermic group (P < 0.05). The catecholamine requirement was also lower in the hypothermic than in the normothermic dogs (P < 0.05).

CONCLUSIONS

Long-term mild to moderate hypothermia with ECLHA induced immediately after cardiac arrest improved survival as well as cerebral and cardiac outcomes.

Cardiopulmonary cerebral resuscitation using emergency cardiopulmonary bypass, coronary reperfusion therapy and mild hypothermia in patients with cardiac arrest outside the hospital

OBJECTIVES

The purpose of this study was to evaluate the efficacy of an alternative cardiopulmonary cerebral resuscitation (CPCR) using emergency cardiopulmonary bypass (CPB), coronary reperfusion therapy and mild hypothermia.

BACKGROUND

Good recovery of patients with out-of-hospital cardiac arrest is still inadequate. An alternative therapeutic method for patients who do not respond to conventional CPCR is required.

METHODS

A prospective preliminary study was performed in 50 patients with out-of-hospital cardiac arrest meeting the inclusion criteria. Patients were treated with standard CPCR and, if there was no response, by emergency CPB plus intra-aortic balloon pumping. Immediate coronary angiography for coronary reperfusion therapy was performed in patients with suspected acute coronary syndrome. Subsequently, in patients with systolic blood pressure above 90 mm Hg and Glasgow coma scale score of 3 to 5, mild hypothermia (34 C for at least two days) was induced by coil cooling. Neurologic outcome was assessed by cerebral performance categories at hospital discharge.

RESULTS

Thirty-six of the 50 patients were treated with emergency CPB, and 30 of 39 patients who underwent angiography suffered acute coronary artery occlusion. Return of spontaneous circulation and successful coronary reperfusion were achieved in 92% and 87%, respectively. Mild hypothermia could be induced in 23 patients, and 12 (52%) of them showed good recovery. Factors related to a good recovery were cardiac index in hypothermia and the presence of serious complications with hypothermia or CPB.

CONCLUSIONS

The alternative CPCR demonstrated an improvement in the incidence of good recovery. Based upon these findings, randomized studies of this hypothermia are needed.

Successful resuscitation of a verapamil-intoxicated patient with percutaneous cardiopulmonary bypass

OBJECTIVE

To describe our experience with the use of percutaneous cardiopulmonary bypass as a therapy for cardiac arrest in an adult patient intoxicated with verapamil.

DESIGN

Case report.

SETTING

Emergency department of a university hospital.

PATIENT

A patient with cardiac arrest after severe verapamil intoxication.

INTERVENTIONS

Percutaneous cardiopulmonary bypass and theophylline therapy.

CASE REPORT

A 41-yr-old white male had taken 4800-6400 mg of verapamil in a suicide attempt. On arrival of the ambulance physician, the patient was conscious with weak palpable pulses and was transported to a nearby hospital. The patient developed a pulseless electrical activity, and cardiopulmonary resuscitation was started. Despite all advanced life support efforts, the patient remained in cardiac arrest. Therefore, he was transferred under ongoing cardiopulmonary resuscitation to our department, where percutaneous cardiopulmonary bypass was initiated immediately (2.5 hrs after cardiac arrest). The first verapamil serum concentration obtained at admittance to our institution was 630 ng/mL. After several ineffective intravenous epinephrine applications, the administration of 0.48 g of theophylline as an intravenous bolus 6 hrs and 18 mins after cardiac arrest led to the return of spontaneous circulation. The patient remained stable and was transferred to an intensive care unit the same day. He woke up on the 12th day and was extubated on the 18th day. After transfer to a neuropsychiatric rehabilitation hospital, he recovered totally.

CONCLUSION

In patients with cardiac arrest attributable to massive verapamil overdose, percutaneous extracorporeal cardiopulmonary bypass can provide adequate tissue perfusion and sufficient cerebral oxygen supply until the drug level is reduced and restoration of spontaneous circulation can be achieved.

Experience with emergency cardiac surgery following institution of percutaneous cardiopulmonary support

Between August 1992 and February 1998, 43 patients were treated with percutaneous cardiopulmonary support (PCPS) in our institution, and 8 of them subsequently required emergency cardiac surgery. There were 3 males and 5 females with a mean age of 63 years (range, 37 to 81 years). The etiology of shock in these 8 patients was acute myocardial infarction in 3, postinfarction left ventricular (LV) free wall rupture in 1, postinfarction ventricular septal perforation (VSP) in 1, LV free wall rupture and VSP in 1, and fatal arrhythmia due to severe aortic valvular disease in 2. The mean time interval from the onset of cardiogenic shock to the institution of PCPS was 77 min (range, 18 to 183 min). The mean time interval from the institution of PCPS until surgery was 145 min (range, 40 to 603 min). The surgical procedures were coronary artery bypass grafting (CABG) in 3 patients, closure of the LV rupture and/or closure of VSP in 3, and aortic valve replacement in 2. Six patients were weaned from PCPS, and 2 patients were discharged from the hospital (discharge rate, 25%). Although the results of emergency cardiac surgery following PCPS still are not satisfactory, we continue to apply PCPS and perform appropriate surgical procedures to improve the survival rate of the patients who would die without PCPS.

Use of percutaneous cardiopulmonary support of patients with fulminant myocarditis and cardiogenic shock for improving prognosis

Percutaneous cardiopulmonary support was used in 9 patients with fulminant myocarditis and cardiogenic shock. Although 2 of the patients died, 7 improved and were able to resume social activities. Percutaneous cardiopulmonary support should be administered routinely to patients with fulminant myocarditis developing into cardiogenic shock.

Percutaneous cardiopulmonary bypass for therapy resistant cardiac arrest from digoxin overdose

A 79-year 65 kg male called the ambulance service 4 h after ingestion of 100 tablets of digoxin 0.1 mg complaining of nausea and vomiting. The ECG showed an idioventricular escape rhythm with a heart rate of 30/min. After 0.5 mg atropine, heart rate increased to 80/min. Soon after admission to the emergency department, the patient developed electromechanical dissociation. Due to persistent cardiac arrest, percutaneous cardiopulmonary bypass was started, and the ECG rhythm changed to ventricular fibrillation. Several attempts to terminate ventricular fibrillation by electrical defibrillation failed. Fifty-eight minutes after cardiac arrest, antidigoxin-Fab was administered and 1 h 25 min after cardiac arrest, ventricular fibrillation was terminated by the tenth electrical defibrillation attempt. Initially, the patient's overall status improved over the next 2 days, but then he developed a severe adult respiratory distress syndrome and died of unresponsive septic shock 12 days after ingestion of digoxin. This case demonstrates that percutaneous cardiopulmonary bypass may provide support in patients with cardiac arrest due to massive digoxin overdose. This temporary support can maintain adequate tissue perfusion during the time required for drug neutralization in order to achieve successful defibrillation. Percutaneous cardiopulmonary bypass should be considered in patients with severe, but temporary cardiac dysfunction due to a life-threatening drug overdose.

Percutaneous venoarterial extracorporeal membrane oxygenation for emergency mechanical circulatory support

In this retrospective study we report our initial experience with percutaneous venoarterial extracorporeal membrane oxygenation in the emergency treatment of intractable cardiogenic shock or pulseless electrical activity. Between January 1994 and July 1995, percutaneous venoarterial extracorporeal membrane oxygenation was attempted in seven patients (pulseless electrical activity, five patients; cardiogenic shock, two patients). In two of the seven patients, efforts at arterial cannulation resulted in cannula perforation at the level of the iliac artery. In the remaining five patients, percutaneous venoarterial extracorporeal membrane oxygenation could be established and was maintained for 3-84 h. Major bleeding remained a common complication during extracorporeal membrane oxygenation despite the use of heparin-coated bypass circuits and was responsible for death during extracorporeal membrane oxygenation in one patient. The remaining four patients could be weaned from mechanical circulatory support within 24 h, two after surgical interventions (resection of right atrial tumor, heart transplantation), one after thrombolytic therapy. In one patient, cardiac function recovered spontaneously after 6 h on venoarterial extracorporeal membrane oxygenation. Three patients were discharged from hospital, two of them made a full recovery, one sustained severe hypoxic brain injury. A few patients with intractable cardiogenic shock or pulseless electrical activity can be resuscitated with the help of emergency percutaneous venoarterial extracorporeal membrane oxygenation. Emergency venoarterial extracorporeal membrane oxygenation is associated with a high rate of complications and its use should therefore be limited to selected patients with a rapidly correctable underlying cardiopulmonary pathology (anatomic, metabolic or hypothermic) who do not respond to conventional advanced cardiac life support.

Effects of intraaortic balloon pumping on coronary and carotid flow during percutaneous cardiopulmonary support

Previous studies have suggested an improved clinical outcome when percutaneous cardiopulmonary support is combined with intraaortic balloon counterpulsation in patients with cardiogenic shock. We evaluated the effect of combined intraaortic balloon counterpulsation and percutaneous cardiopulmonary support therapy on coronary and cerebral blood flow by Doppler measurements in the coronary and the carotid arteries in a patient with cardiac arrest. During pacemaker stimulation, intraaortic balloon counterpulsation in addition to percutaneous cardiopulmonary support markedly improved coronary and carotid blood flow. Possible mechanisms are discussed.

The determinant of severe cerebral dysfunction in patients undergoing emergency extracorporeal life support following cardiopulmonary resuscitation

We investigated the factors associated with cerebral dysfunction in patients undergoing extracorporeal life support (ECLS) following conventional advanced cardiac life support (ACLS). The subjects were 9 patients in whom ECLS was started following ACLS because of intractable cardiac arrest. We investigated whether the irreversibility of cerebral dysfunction during ECLS was related to the cardiopulmonary resuscitation (CPR) time, arterial pH and blood gases, hemoglobin concentration (Hb), peak arterial pressure (PAP) before the start of ECLS and total doses of epinephrine and sodium bicarbonate administered during CPR. Two of the 3 patients who recovered consciousness were weaned from ECLS and survived, while all 6 patients who did not recover from coma were not weaned and died. There was no difference in the CPR time, Hb and PAP before the start of ECLS along with total doses of epinephrine and sodium bicarbonate administered during CPR between the patients who recovered consciousness and those who did not. In addition, there was no difference in arterial pH and blood gases except the arterial oxygen tension (PaO2) between the groups. The PaO2 values before the start of ECLS in the patients who remained in coma ranged from 34 to 58 mmHg, whereas those in the patients who recovered consciousness ranged from 132 to 442 mmHg. The PaO2 values before the start of ECLS in the patients who remained in coma were less than 60 mmHg, whereas those in the patients who recovered consciousness were over 60 mmHg. The present study suggests that hypoxemia during CPR may play a major role in severe cerebral dysfunction in patients undergoing ECLS and PaO2 during CPR.

Cardiopulmonary support for complex angioplasty

The role of cardiopulmonary support (CPS) in interventional procedures is currently in evolution. The authors review the clinical applications and technical considerations involved in CPS including discussion of indications, hemodynamic effects, complications, and prophylactic versus stand-by techniques. Use of the technique in high risk percutaneous transluminal coronary angioplasty patients is discussed.

Emergency and long-term extracorporeal life support following acute myocardial infarction: rescue from severe cardiogenic shock related to stunned myocardium

There has been no report regarding therapy of extracorporeal life support (ECLS) that showed stunned myocardium echocardiographically and electrocardiographically in patients with acute myocardial infarction. ECLS was performed in eight patients with cardiogenic shock or arrest unresponsive to catecholamines and intra-aortic balloon pumping following myocardial infarction; these patients required prolonged external cardiac massage. After the initiation of ECLS, both blood pressure and metabolic acidosis improved in all patients. Four of eight patients were weaned from ECLS after a mean of 69.3 h, which was far longer than previously reported in patients with ischemic heart disease. Three of these patients survived, and cardiac function recovered to NYHA class II in two of the survivors and class III in the other. The other five patients did not recover from coma during ECLS and died. A marked improvement of ventricular wall motion was seen in two survivors with the disappearance of pathologic Q waves after the initiation of ECLS. No occlusion of the coronary arteries or bypass grafts was observed in any of the survivors. These findings suggested the existence of stunned myocardium with myocardial reperfusion. The recovery of stunned myocardium may be delayed for days or even weeks, hence the extended period of ECLS therapy was theoretically justifiable. We conclude that long-term ECLS is a useful therapeutic method for patients with severe cardiogenic shock that is related to stunned myocardium.