Prospective study of the value of necropsy examination in early death after cardiac surgery

Risk factors of sepsis after open congenital cardiac surgery in infants: a pilot study

Background: Postsurgical sepsis is one of the main causes of the high mortality and morbidity after open congenital heart surgery in infants.  This study aimed to evaluate the role of cardiopulmonary bypass duration, thymectomy, surgical complexity, and nutritional status on postsurgical sepsis after open congenital cardiac surgery in infants.Methods: A total of 40 patients <1 year of age with congenital heart disease, Aristotle Basic Score (ABS) ≥6 were followed for clinical and laboratory data before and after surgery until the occurrence of signs or symptoms of sepsis or until a maximum of 7 days after surgery. Bivariate analyses were performed. Variables with p≤0.200 were then included for logistic regression.Results: Duration of cardiopulmonary bypass ≥90 minutes was associated with 5.538 increased risk of postsurgical sepsis in comparison to those ≤90 minutes (80% vs 25%, RR=5.538, p=0.006). No association was observed between the incidence of postsurgical sepsis with poor nutritional status (86% vs 84%, RR=1.059, p=1.000), thymectomy (and 50% vs 76%, RR=0.481, p=0.157), and Aristotle Basic Score (p=0.870).Conclusion: Cardiopulmonary bypass time influences the incidence of sepsis infants undergoing open congenital cardiac surgery. Further studies are needed to elaborate a number of risk factors associated with the incidence of sepsis in this population.

Pulmonary Complications After Cardiac Surgery

Over the past two decades there has been a steady evolution in the practice of adult cardiac surgery with the introduction of “off-pump” surgery. However, respiratory complications remain a leading cause of postcardiac surgical morbidity and can prolong hospital stays and increase costs. The high incidence of pulmonary complications is in part due to the disruption of normal ventilatory function that is inherent to surgery in the thoracic region. Furthermore, patients undergoing such surgery often have underlying illnesses such as intrinsic lung disease (e.g., chronic obstructive pulmonary disease) and pulmonary dysfunction secondary to cardiac disease (e.g., congestive heart failure) that increase their susceptibility to postoperative respiratory problems. Given that many patients undergoing cardiac surgery are thus susceptiple to pulmonary complications, it is remarkable that more patients do not suffer from them during and after cardiac surgery. This is to a large degree because of advances in anesthetic, surgical and critical care that, for example, have reduced the physiological insults of surgery (e.g., better myocardial preservation techniques) and streamlined care in the immediate postoperative period (e.g., early extubation). Moreover, the development of minimally invasive surgery and nonbypass techniques are further evidence of the attempts at reducing the homeostatic disruptions of cardiac surgery. This review examines the available information on the incidences, consequences, and treatments of postcardiac surgery respiratory complications.

[Cardiac surgery in underlying chronic pulmonary disease. Prognostic implications and efficient preoperative evaluation]

Cardiac surgery in patients with chronic pulmonary diseases carries a high risk of postoperative pulmonary complications (ppc) because both are known to cause ppc. Autopsy studies have revealed ppc as the main cause of mortality in approximately 5-8% of patients after cardiac surgery. Not all pulmonary diseases are high risk comorbidities in cardiac surgery: whereas chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea significantly increase the risk of ppc, a well controlled asthma does not carry an additional risk of ppc. A thorough preoperative risk stratification is crucial for risk estimation and some validated risk calculators, such as the Canet risk score exist. Surprisingly the additional value of pulmonary function testing beyond a thorough patient history and physical examination is low. No validated thresholds exist in pulmonary function testing below which cardiac surgery should be denied if clearly indicated. Perioperative strategies for risk reduction should be applied to all patients whenever possible.

The medical malpractice in Milan-Italy. A retrospective survey on 14 years of judicial autopsies

The medical malpractice is a rising and central topic for the forensic pathologist and forensic autopsies are a mandatory step in the judicial evaluation of the suspected medical malpractice. Reliable national and international registers about the medical malpractice are still missing and nowadays the necroscopic archives are therefore one of the best sources of data about such a complex phenomenon. We analyzed the archive of the Institute of Forensic Medicine of the Milan University from 1996 to 2009 and selected 317 lethal cases of suspected medical malpractice. The mean age of our cases was 60±18 years for males and 58±19 years for the females. In 70% of such cases the patient death occurred in a hospital setting. The first 24h of hospitalization turned out to be the hottest period for deaths followed by malpractice claims. The surgical branches were obviously the most involved, with abdominal surgery, orthopedics, neurosurgery and gynecology as the main contributors. Just 12% of the total amount of cases came from all the internistic branches put together. Non-hospital malpractice was typically caused by misdiagnosed myocardial infarctions and aortic ruptures. A full forensic report was present in 71 cases (all belonging to the 2007-2009 period): in 69% of cases the judicial autopsy revealed as a sufficient tool for diagnosing the cause of death; medical malpractice was confirmed in only 17% of the whole cases and a causal link between the ascertained malpractice and the patient death was recognized in only 12.7% cases.

Comparative effectiveness of preventative therapy for venous thromboembolism after coronary artery bypass graft surgery

BACKGROUND

Controversy exists regarding the optimal preventative therapy for venous thromboembolism (VTE) after coronary artery bypass graft (CABG) surgery. We sought to compare the effectiveness and safety of the most commonly used regimens.

METHODS AND RESULTS

We assembled a cohort of 92 699 patients who underwent CABG between 2004 and 2008, using the Premier database. Patients were categorized by method of VTE prevention initiated within 48 hours of surgery, including no preventative therapy (n=55 400), mechanical preventative therapy (n=21 162), subcutaneous unfractio--nated or low-molecular-weight heparin (n=10 718), subcutaneous fondaparinux (n=88), and concurrent mechanical-chemical therapy (n=5331). The incidence of VTE and major bleeding events within 6 weeks of CABG were compared, using multivariable and propensity score adjustment. The overall incidence of VTE for the entire cohort was 0.74%, and the incidence of major bleeding was 1.43%. VTE and bleeding events occurred with similar incidence in each of the patient categories (VTE: 0.70%, 0.79%, 0.81%, 1.14%, and 0.73%; major bleeding: 1.36%, 1.45%, 1.69%, 3.41%, 1.50%; no prevention, mechanical prevention, subcutaneous heparin, subcutaneous fondaparinux, concurrent mechanical-chemical prevention, respectively). Compared with receiving no prevention, the use of mechanical prevention or subcutaneous heparin did not significantly reduce the risk of VTE or change the risk of major bleeding (P=NS).

CONCLUSION

Venous thromboembolism occurs infrequently after CABG. Compared with the use of no prevention, the administration of chemical or mechanical preventative therapies to CABG patients does not appreciably lower the risk of VTE. These data provide support for the common practice of administering no VTE preventative therapy after CABG, used for nearly 60% of patients within this cohort.

Pulmonary embolism following coronary artery bypass grafting

BACKGROUND

Pulmonary embolism (PE) is a life-threatening complication, with a deceptive clinical presentation following coronary artery bypass grafting (CABG).

METHODS

We identified 13 studies on PE in post-CABG patients, spanning a period of 34 years.

RESULTS

The overall cumulative incidence of PE following CABG was 1.3% (111 PEs in 8553 CABGs).

CONCLUSION

We suggest further prospective randomized studies to examine the effect of saphenous system vein grafting, and choice of low molecular weight heparin prophylaxis on the incidence of post-CABG PE.

Medico-legal autopsy in postoperative hemodynamic collapse following coronary artery bypass surgery

Sudden unexpected postoperative hemodynamic collapse with a high mortality develops in 1–3% of patients undergoing coronary artery bypass surgery (CABG). The contribution of surgical graft complications to this serious condition is poorly known and their demonstration at autopsy is a challenging task. Isolated CABG was performed in 8,807 patients during 1988–1999. Of the patients, 76 (0.9%) developed sudden postoperative hemodynamic collapse resulting in subsequent emergency reopening of the median sternotomy and open cardiac massage. Further emergency reoperation could be performed in 62 (82%) whereas 14 patients died prior to reoperation and a further 21 did not survive the reoperation or died a few days later. All 35 (46%) patients who did not survive were subjected to medico-legal autopsy combined with postmortem cast angiography. By combining clinical data with autopsy and angiography data, various types of graft complications were observed in 27 (36%, 1.3 per patient) of the 76 patients with hemodynamic collapse. There were no significant differences in the frequency (33 vs. 40%) or number of complicated grafts per patient (1.2 vs. 1.4) between those who survived reoperation and who did not. Autopsy detected 25 major and minor findings not diagnosed clinically. Postmortem cast angiography visualized 2 graft twists not possible to detect by autopsy dissection only. Surgical graft complications were the most frequent single cause for sudden postoperative hemodynamic collapse in CABG patients leading to a fatal outcome in almost half of the cases. Postmortem angiography improved the accuracy of autopsy diagnostics of graft complications.

Coronary artery bypass graft and/or valvular operations following prior pneumonectomy: report of four new patients and review of the literature

BACKGROUND

The reported experience is sparse for patients with prior pneumonectomy who are undergoing surgery for ischemic or valvular heart disease. Such surgery poses special technical challenges. To expand the experience with this challenging clinical intervention, we reviewed the reported patients with prior pneumonectomy who were undergoing cardiac surgery as well as the experience at the Cleveland Clinic.

METHODS

A MEDLINE search of the literature for articles published in the English language from 1966 to August 2006 was conducted using the search terms "pneumonectomy" and "cardiac surgery." We included all available individually described patients and also reviewed the Cardiovascular Information Registry at the Cleveland Clinic from 1972 to 2006.

RESULTS

A total of 19 individually described patients in 13 reports were available, 15 of which had previously been reported and 4 that were newly reported from our institution (1 of whom had undergone two operations separated by 8 years). Of the 20 operations performed in these 19 patients, coronary artery bypass grafting (CABG) alone was performed in 15 patients (75%), valve replacement or repair was performed in 4 patients (20%), and CABG with both aortic valve replacement and mitral valve repair was performed in 1 patient (5%). Most patients (13; 68%) had undergone left pneumonectomy. For these 19 patients, the postoperative mortality rate was 16%. Postoperative complications followed 10 of the operations (50%).

CONCLUSIONS

Although complications and postoperative deaths occurred more frequently than in other high-risk patient groups (eg, those with COPD undergoing cardiac surgery), this experience suggests that cardiac surgery can be undertaken with a reasonable likelihood of a favorable outcome in this challenging population, justifying the approach in appropriately selected and counseled patients.

Autopsy findings in patients on postcardiotomy extracorporeal membrane oxygenation (ECMO)

OBJECTIVES

To assess the clinical sensitivity of causes of death, concomitant diseases and postoperative complications including thromboembolic events in ECMO patients.

METHODS

Between January 2000 and December 2004 154/202 patients (76.2%) died after postcardiotomy ECMO circulatory support. Autopsy was performed in 78 (50.6%) consecutive patients. Clinical and post-mortem data were prospectively recorded and compared concerning causes of death and postoperative complications including venous and arterial thromboembolisms and significant comorbidities.

RESULTS

Mean age was 62.1+/-11.3 years, ejection fraction was 43.4+/-17.3%. 39.7% were emergency operations including acute coronary syndrome in 25.6% and preoperative cardiogenic shock in 28.2%. Successful ECMO weaning rate was 43.6%. Mean postoperative survival was 11.3 days. Premortem unknown concomitant diseases were found in 63 patients (80.8%) with clinical relevance in 9 patients (11.5%). Clinically unrecognized postoperative complications were found in 59 patients (75.6%) including acute cerebral infarction (n=7), acute bowel ischemia (1), intestinal perforation (3), pneumonia (4), venous thrombus formation (25) and systemic thromboembolic events (24). Clinically based causes of death were cardiac in 62.8%, multi-organ failure in 10.3%, cerebral in 5.1%, respiratory in 10.3%, fatal pulmonary embolism in 2.6%, technical in 5.1%, and others in 3.8%. Unexpected causes of death were found by autopsy in 22 patients (28.2%) including myocardial infarction (n=5), acute heart failure (4), fatal pulmonary embolism (2), pneumonia (2), ARDS (1), lung bleeding (1), fatal cerebrovascular event (4) and multiorgan failure (3).

CONCLUSIONS

In ECMO patients major discrepancies between clinical and post-mortem examination were found. The true incidence of thromboembolic events is highly underestimated by clinical evaluation.

Implementation of the 2005 Coroners Rules Amendments: a survey of practice in England and Wales

BACKGROUND

On 1 June 2005, amendments to the Coroners Rules 1984 were introduced in England and Wales. These principally cover the retention of tissues from autopsies and their subsequent disposal. This study assesses regional variations in the interpretations of the amendments, and their impact on local autopsy practice in Oxford.

METHODS

A questionnaire was circulated to pathologists in 120 coronial jurisdictions, addressing conditions under which histological material could be retained. A local review of autopsy practice was conducted before and after the introduction of the amendments.

RESULTS

Questionnaires were returned from 71 coronial jurisdictions. 35 (49%) coroners provided written guidelines on their interpretation of the amendments. In 52 (73%) jurisdictions, pathologists are authorised to retain material to confirm/refine causes of death from natural causes. In 77% of jurisdictions, coroner's officers are responsible for obtaining instructions from the next of kin on subsequent retention, use or disposal of retained tissues. In Oxford, there has been a reduction in the proportion of cases in which histology is taken, but an increase in the proportion of cases in which a histology report is issued.

CONCLUSIONS

There is considerable regional variation in the interpretation of the 2005 Coroners Rules Amendments. These variations have potentially important implications for clinical practice.

Significant value of autopsy for quality management in cardiac surgery

OBJECTIVE

With recent advances in diagnostic imaging, the value of autopsy has been called into question. The aim of our study was to assess the current impact of autopsy for early postoperative quality management in cardiac surgery.

METHODS

Between 2000 and 2003, a total of 14,313 patients underwent cardiac surgery at our center. Of these, 898 patients (6.3%) died, and autopsy was performed in 468 cases (52.1%). Data from clinical and postmortem examination were prospectively analyzed regarding causes of death, postoperative complications, concomitant diseases, and surgery-associated pathologic findings.

RESULTS

Mean age was 68.7 years. Mean survival was 13.9 postoperative days. On autopsy, causes of death were cardiac in 49.8% of cases (n = 233), respiratory in 8.3% (n = 39), cerebral in 6.4% (n = 30), abdominal in 4.7% (n = 22), multiorgan failure or sepsis in 14.9% (n = 70), pulmonary embolism in 6.6% (n = 31), procedure associated in 8.3% (n = 39), and others in 0.9% (n = 4). Discrepancies between clinical and postmortem determinations of cause of death were found in 108 cases (23.1%). These were acute myocardial infarction (n = 38), low cardiac output (n = 9), respiratory (n = 8), cerebral (n = 5), abdominal (n = 7), multiorgan failure or sepsis (n = 12), pulmonary embolism (n = 18), and procedure associated (11). Clinically unrecognized postoperative complications were found in 364 cases (77.8%). Unknown concomitant diseases were found in 464 cases (99.1%), with potential therapeutic relevance in 90 cases (19.2%). In 85 cases (18.2%), autopsy examination revealed 96 premortem unrecognized surgery-associated pathologic findings.

CONCLUSION

A high overall discrepancy rate between premortem and autopsy diagnoses was recognized. Autopsy revealed clinically relevant information in a significant number of cases. Therefore autopsy remains essential for quality assessment in perioperative treatment.

Molecular mechanisms in male determination and germ cell differentiation

Sex determination and gametogenesis are key processes in human reproduction, and any defect can lead to infertility. We describe here the molecular mechanisms of male sex determination and testis formation; defects in sex determination lead to a female phenotype despite the presence of a Y chromosome, more rarely to a male phenotype with XX chromosomes, or to intersex phenotypes. Interestingly, these phenotypes are often associated with other developmental malformations. In testis, spermatozoa are produced from renewable stem cells in a complex differentiation process called spermatogenesis. Gene expression during spermatogenesis differs to a surprising degree from gene expression in somatic cells, and we discuss here mechanistic differences and their effect on the differentiation process and male fertility.

Mechanisms of death in the early postoperative period following coronary artery bypass grafting for acquired heart disease. A clinicopathological study of 32 cases

OBJECTIVES

A retrospective cardiopathological and clinical study was conducted in order to determine causes of perioperative death following coronary artery bypass grafting (CABG).

EXPERIMENTAL DESIGN

Between January 1992 and June 1995, a total of 5749 CABG procedures were performed at the Heart Center Duisburg (Germany). Following the procedures, 218 patients died in hospital (mortality rate 3.8%). Fifty-eight were autopsied at the Institute of Pathology, Bethesda Hospital, Duisburg, and 32 autopsied cases were amenable to our study. Basis for selection was accessibility of clinical and morphological data and a postoperative death within 30 days.

METHODS

In each case, morphological analysis of the heart and an evaluation of surgical and clinical data were performed in order to draw a conclusion on the mechanism of death.

RESULTS

Using criteria defined by us, the following causes of death were determined: (1) surgical complications (43%); (2) severe coronary artery disease with incomplete revascularization (41%); (3) congestive heart failure (13%); (4) non-cardiac complications (3%).

CONCLUSION

Criteria defined in this study may be useful in evaluations of causes of death after open heart surgery and may help to compare results in future series. Determination of the cause of death is important for the cardiac surgeon to reconsider indications and quality of surgical procedure.

Clinical versus actual outcome in cardiac surgery: a post-mortem study

BACKGROUND

Clinical attribution of the cause of death can be misleading, with the only true outcome measure being post-mortem analysis. Despite this there is very little published data on post-mortems following cardiac surgery.

METHODS

Prospective consecutive post-mortem data were collected on 167 patients (84.4% of all in-hospital cardiac surgical deaths) in a single institution. Clinical diagnoses were compared with post-mortem findings.

RESULTS

The mean age at death was 69.8 with 67.6% male. The proportion undergoing coronary artery bypass graft (CABG) alone was 52.1%, valve surgery 18.6%, valve+CABG 19.2% and other procedures 10.1%. The mean time to death was 7.9 days (range 0-87). The causes of death were cardiac 67.7%, gastrointestinal 9.6%, respiratory 8.4%, haemorrhage/technical failure 4.8%, stroke (cerebrovascular accident) 3.6%, multiorgan failure 3.0%, sepsis 1.8%, malignancy 0. 6% and trauma 0.6%. Post-mortem revealed an unsuspected cause of death in 19 (11.4%). These were gastrointestinal (infarction nine, perforation two), cardiac three, adult respiratory distress syndrome two, technical two and pulmonary embolus one. In addition, an unsuspected lung cancer was found in 1 patient who died of cardiac causes. When cardiac deaths were compared with non-cardiac causes the Parsonnet score was higher 20.0 (+/-1.4) vs. 15.3 (+/-1.6), P=0. 07; and a greater proportion tended to have poor ejection fractions (34 vs. 15%), P=0.12. There was no significant difference between the groups in terms of age, sex, operation, hypertension, diabetes, creatinine and body mass.

CONCLUSIONS

Post-mortem can determine unsuspected diagnoses in a significant proportion of cases. Pre-operative risk factors do not correlate with eventual cause of death. Post-mortem still has an important role to play in cardiac surgery.

Acp. Best practice no 155. Pathological investigation of deaths following surgery, anaesthesia, and medical procedures

The pathological investigation of deaths following surgery, anaesthesia, and medical procedures is discussed. The definition of "postoperative death" is examined and the classification of deaths following procedures detailed. The review of individual cases is described and the overall approach to necropsy and interpretation considered. There are specific sections dealing with the cardiovascular system (including air embolism, perioperative myocardial infarction, cardiac pacemakers, central venous catheters, cardiac surgery, heart valve replacement, angioplasty, and vascular surgery); respiratory system (postoperative pneumonia, pulmonary embolism, pneumothorax); central nervous system (dissection of cervical spinal cord), hepatobiliary and gastrointestinal system; musculoskeletal system; and head and neck region. Deaths associated with anaesthesia are classified and the specific problems of epidural anaesthesia and malignant hyperthermia discussed. The article concludes with a section on the recording of necropsy findings and their communication to clinicians and medicolegal authorities.

Post-mortem examination after cardiac surgery

Following a recent enquiry into surgery at a paediatric cardiac centre in England, there will be substantial changes in the way that the success and failure of surgical procedures will be monitored and investigated. Post-mortem examinations on patients dying after cardiac surgery are likely to be performed and reported in more detail. This review describes the protocol that we have developed and summarizes recent clinical and pathological studies that have increased our understanding of postoperative pathophysiology. Close attention should be paid to the history, particularly the operation note. Cardiac failure is the commonest cause of death. We believe this is a clinicopathological diagnosis and provide definitions of preoperative and perioperative cardiac failure. Haemorrhage, stroke, pulmonary emboli and infection are other important causes of death. Methods of dissection are suggested for bypass grafts and valve replacements. Two recent studies show that the post-mortem examination provides answers to most clinical questions and reveals an unexpected cause of death in 10-15% of patients. There are limitations however: an incomplete or indeterminate cause of death is found in 14-25% of patients, most commonly sudden clinically unexplained death or clinically unexplained cardiac failure soon after surgery.