A clinical-pathological study of nonsurvivors of newborn ECMO

Acute Brain Injury in Infant Venoarterial Extracorporeal Membrane Oxygenation: An Autopsy Study

OBJECTIVES

Characterization of the types and timing of acute brain injury in infant autopsy patients after extracorporeal membrane oxygenation.

DESIGN

Retrospective cohort study.

SETTING

Single tertiary-care center.

PATIENTS

Infants supported on extracorporeal membrane oxygenation.

MEASUREMENTS AND MAIN RESULTS

Clinical and pathologic records were reviewed for infant extracorporeal membrane oxygenation patients who had undergone brain autopsy in a single center between January 2009 and December 2018. Twenty-four patients supported on venoarterial extracorporeal membrane oxygenation had postmortem examination with brain autopsy. Median age at extracorporeal membrane oxygenation initiation was 82 days (interquartile range, 11-263 d), median age at time of death was 20 weeks (interquartile range, 5-44 wk), and median extracorporeal membrane oxygenation support duration was 108 hours (interquartile range, 35-366 hr). The most common acute brain injury found at autopsy was hypoxic-ischemic brain injury (58%) followed by intracranial hemorrhage (29%). The most common types of intracranial hemorrhage were intracerebral (17%), subarachnoid (17%), and subdural (8%). Only five infants (21%) did not have acute brain injury. Correlates of acute brain injury included low preextracorporeal membrane oxygenation oxygen saturation as well as elevated liver enzymes, total bilirubin, and lactate on days 1 and 3 of extracorporeal membrane oxygenation. Gestational age, Apgar scores, birth weight, extracorporeal membrane oxygenation duration, anticoagulation therapy, and renal and hepatic impairments were not associated with acute brain injury.

CONCLUSIONS

Acute brain injury was observed in 79% of autopsies conducted in infants supported on extracorporeal membrane oxygenation. Hypoxic-ischemic brain injury was the most common type of brain injury (58%), and further associations with preextracorporeal membrane oxygenation acute brain injury require additional exploration.

Prognosis and Outcome of Neonates Treated Either with Veno-Arterial (VA) or Veno-Venous (VV) ECMO

A comparison was done between neonates requiring veno-arterial (VA) ECMO (too small jugular vein, inability to insert a 12 Fr double lumen catheter or cardio-circulatory instability) and neonates treated with veno-venous (VV) ECMO in the same period of time. From 1991-1995 ECMO was done in 48 neonates after failure of maximum conventional treatments, NO-inhalation and HFOV. 30/48 babies were treated with VV-ECMO, with a switch to VA-ECMO later on in 3 of them. In 18 infants VA-ECMO was installed primarily. Differences between the VA- and VV-ECMO group were: the 01 was higher in the VV-treated babies (62±20 vs. 48±13, p < 0.03), as were birth weight (3385±570 vs. 2963±653 g, p< 0.04), gestational age (39.7 ± 1.6 vs. 37.9 ± 2.7 weeks, p< 0.01) and MAP (18.7 ± 2.2 vs. 17.1 ± 2.4 cm H2O, p< 0.05). Severe ICH's occurred more frequently in the VA-treated babies (29 vs. 7%, p< 0.05), the rate of other complications was equal. The mortality rates were 43% (VA) and 15% (VV), p< 0.05. About one third of neonatal ECMO candidates will be treated with VA-ECMO, even if the VV-ECMO technique is available. Need for VA-ECMO implies - due to a higher number of preterm babies and a greater severity of illness before ECMO - a higher incidence of ICH's and a higher mortality rate.

Discrepancies between autopsy and clinical findings among patients requiring extracorporeal membrane oxygenator support

Discrepancy between clinical and autopsy diagnosis in children supported on extracorporeal membrane oxygenation (ECMO) has not been previously described. To assess the utility of autopsy examination in children supported on ECMO and assess discrepancies between premortem and postmortem diagnosis in these patients. Retrospective chart review. General pediatric and cardiac intensive care units (ICUs) in a tertiary children's hospital. The hospital's ECMO database was queried for patients supported on ECMO from 2000 through 2010 who died and underwent autopsy examination. Fifty-four autopsies were performed in 139 nonsurvivors (28%) who required ECMO support in the pediatric and cardiac ICU. Major discrepancies between premortem and postmortem diagnoses were found in 29 patients (53.7%). The commonest missed diagnosis was myocardial infarction that occurred in 16 patients, followed by adrenal hemorrhage in three patients. Five patients with a cardiac diagnosis had both major (type 1 discrepancy) and minor (type 2 discrepancy) discrepancies. Surgical complications were noted in four postmortem study with three of them being class 1 discrepancy. We report significant discrepancy between autopsy and clinical findings among ECMO-supported pediatric patients. Our findings underscore the need for enhanced premorbid surveillance in patients supported on ECMO.

Symmetrical peripheral gangrene in four pediatric cardiac surgery patients receiving extracorporeal membrane oxygenation

Symmetrical peripheral gangrene (multilimb ischemia without large artery occlusion) is a rare condition usually associated with disseminated intravascular coagulation, hemodynamic compromise, and/or sepsis. However, it has not been described in patients on extracorporal membrane oxygenation (ECMO). Over a 5 year period, four pediatric patients developed symmetrical peripheral gangrene on ECMO after cardiac surgery. They subsequently died and came to autopsy. History, physical examination, and laboratory studies were examined. Gross and microscopic autopsy material was reviewed. Patients were 11 days to 13 years old. Extracorporal membrane oxygenation duration was 11-22 days, and limb ischemia began 2-4 days before death. Three patients had rapid onset, with ischemia developing in <48 hours. In the fourth, ischemic changes began as focal lesions and gradually spread. Two patients were septic. Three had evidence of other end-organ damage. Pressors were used in 3 patients before the limb ischemia. Autopsies disclosed ischemic changes involving all limbs, with confluent ecchymoses. In a detailed examination in 1 case, large arteries of the extremities were patent. Involved skin and soft tissue showed bland fibrin thrombi in the microcirculation, with tissue necrosis and hemorrhage. This report describes the first 4 cases of symmetrical peripheral gangrene complicating ECMO. The 4 pediatric patients all had recent surgery for congenital cardiac disease, and all had significant exposure to ECMO prior to developing limb ischemia. Symmetrical peripheral gangrene is an unusual complication of ECMO that may arise in the setting of disseminated intravascular coagulation, sepsis, or other hemostatic and/or hemodynamic imbalance.

Neurological complications of extracorporeal membrane oxygenation in children

OBJECT

Extracorporeal membrane oxygenation (ECMO) is a potentially life-saving treatment for patients in refractory cardiorespiratory failure. Neurological complications that result from ECMO treatment are known to significantly impact patient survival and quality of life. The purpose of this study was to review the incidence of neurological complications of ECMO in the pediatric population and the role of neurosurgery in the treatment of these patients.

METHODS

Data were obtained from the national Extracorporeal Life Support Organization (ELSO) Registry for the years 1990 to 2009. The neurological complications recorded by the registry include CNS hemorrhage, CNS infarction, and seizure. The ECMO Registry at the authors' institution was then searched, and 3 pediatric patients who had undergone craniotomy during ECMO treatment were identified.

RESULTS

Children in the ELSO Registry who were treated with ECMO survived to hospital discharge in 65% of cases. Intracranial hemorrhage occurred in 7.4% of the ECMO-treated patients, with 36% of those surviving to hospital discharge. Hemorrhage was more likely in patients younger than 30 days old and in those requiring ECMO for cardiac indications. Cerebral infarction occurred in 5.7% of all ECMO-treated patients. Clinically diagnosed seizures occurred in 8.4% of all ECMO-treated patients. The ECMO Registry at the authors' institution revealed that 1898 patients were treated there. Intracranial hemorrhage was diagnosed in 81 patients (5.8%), and 3 of these patients were treated with craniotomy. Two of the patients were alive with minimal neurological impairment and normal school performance at 10 and 16 years of follow-up.

CONCLUSIONS

Intracranial hemorrhage is a serious complication of ECMO treatment. While the surgical risk is substantial, there may be a role for surgical evacuation of hemorrhage in well-selected patients.

Laboratory and clinical predictors of thrombosis and hemorrhage in 29 pediatric extracorporeal membrane oxygenation nonsurvivors

Extracorporeal membrane oxygenation (ECMO) is a life-saving therapy for infants and children with cardiac and respiratory failure. However, thrombosis and hemorrhage are common complications. To determine clinical and laboratory predictors of thrombosis and hemorrhage resulting from ECMO, records and slides were reviewed from 29 consecutive autopsies from 2004 through 2008 of pediatric patients who received ECMO at our institution. Laboratory results, including prothrombin time, activated partial thromboplastin time, platelet count, fibrinogen level, and activated clotting time, were analyzed, as was heparin dosing. Thrombosis and hemorrhage were very common, with 1 or both seen in 86% of patients. Sixty-nine percent had thrombosis, and 52% had hemorrhage after ECMO initiation, including intracranial hemorrhage in 33% of the patients in whom brain examination was permitted. Hemorrhage and thrombosis coexisted in 31% of patients. Thrombosis was significantly more common in patients with congenital cardiac disease. Duration of ECMO therapy, being on ECMO at death, sepsis, and patient age and sex did not predict hemorrhage or thrombosis at autopsy. Laboratory tests were poor predictors of thrombosis and hemorrhage, with no correlation between these complications and prothrombin time, partial thromboplastin time, platelet count, fibrinogen level, activated clotting time, or heparin dose. In conclusion, thrombosis and hemorrhage continue to be frequent complications among patients who die during or after ECMO therapy. Patients with congenital cardiac disease appear especially susceptible to thrombosis on ECMO. Prothrombin time, partial thromboplastin time, platelet count, fibrinogen level, activated clotting time, and heparin dose are poor predictors of thrombosis or hemorrhage for pediatric patients who die after ECMO.

Histopathological features of open lung biopsies in children treated with extracorporeal membrane oxygenation (ECMO)

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has become an established treatment for severe respiratory distress in a range of pediatric conditions. This study describes the histopathological features in a series of 22 children receiving ECMO therapy in whom open lung biopsy was carried out.

AIMS

To describe the histopathological features of open lung biopsies in children receiving ECMO therapy.

STUDY DESIGN

Retrospective review of clinical material.

SUBJECTS

Children receiving ECMO therapy in whom open lung biopsy was carried out.

RESULTS

In those investigated in infancy, open lung biopsy allowed a definite diagnosis to be made of the underlying condition in more than 90% of cases. In older children, the histopathological changes were more non-specific and, although providing useful clinical information, a definitive diagnosis could often not be made. In about a quarter of cases, there are additional pathological features, which may be related to ECMO treatment, such as significant intra-alveolar haemorrhage, but ECMO does not in itself impair the diagnostic usefulness of open lung biopsy in these selected patients.

CONCLUSION

Open lung biopsy provides clinically useful information in infants receiving ECMO therapy. The histopathological changes may be complex and represent both the effects of ECMO and progression of the underlying disease.

Histological changes in the hearts of non-survivors of the UK collaborative trial of neonatal ECMO (extra corporeal membrane oxygen)

AIMS

To study the cardiac pathology of infants enrolled in the UK collaborative trial of neonatal ECMO (extra corporeal membrane oxygen) who died following random allocation to a trial arm.

METHODS

During the trial, 81 infants died. The hearts of 26 babies were received and examined without knowledge of treatment regimen. The control group consisted of 14 infants who received conventional treatment. Twelve were allocated to ECMO; seven received this treatment.

RESULTS

In the control group, four showed minor histological changes. The other hearts were histologically normal. In the group treated with ECMO, four had multiple foci of micro-infarction throughout both ventricles and papillary muscles. There was variable thrombotic vascular occlusion. Three were normal. There was no correlation between cardiac pathology and clinical features. There was a significant difference in the length of survival between the two groups.

CONCLUSIONS

ECMO treatment seems to be associated with clinically significant cardiac pathology. The changes observed may reflect the longevity of survival in the ECMO group rather than an association with the treatment itself. Nevertheless, the findings have significant implications for those monitoring the development of infants surviving ECMO treatment and suggest that the monitoring of myocardial function will be crucial.

Risk factors for intracranial hemorrhage in adults on extracorporeal membrane oxygenation

OBJECTIVE

Intracranial hemorrhage is a recognized complication in neonates and infants on extracorporeal membrane oxygenator support and various risk factors associated with this have been defined. The prevalence and risk factors associated with intracranial hemorrhage in adults on extracorporeal membrane oxygenator support are unknown and this study was performed to define these factors.

METHODS

A retrospective study of adults supported with extracorporeal membrane oxygenators at a single institution between January 1992 and December 1996 was performed. Age, gender, weight, body surface area, renal function, anticoagulation, coagulation variables, blood flow, arterial pressure, arterial cannulation sites, duration of support, extracranial bleeding, native cardiac function and presence of intracranial microemboli were analyzed to determine the risk factors for intracranial hemorrhage.

RESULTS

Fourteen out of 74 adults on extracorporeal membrane oxygenator support had intracranial hemorrhage (18.9%). An increased risk of intracranial hemorrhage showed a positive correlation with female gender (P = 0.02, odds ratio 6.5), use of heparin (P = 0.05, odds ratio 8.5), creatinine greater than 2.6 mg/ dl (P = 0.009, odds ratio 6.5), need for dialysis (P = 0.03, odds ratio 4.3) and thrombocytopenia (P = 0.007, odds ratio 18.3). Diminishing renal function and the need for dialysis were associated with increasing duration of support. Multivariable logistic regression showed female gender and thrombocytopenia, especially with platelet counts less than 50000 cells/mm3 to be the most important predictors of intracranial hemorrhage. Intracranial hemorrhage was associated with a mortality of 92.3% compared with a mortality of 61% in those without intracranial hemorrhage (P = 0.027).

CONCLUSION

Intracranial hemorrhage is a significant complication in adults on extracorporeal membrane oxygenator support. Judicious management of anticoagulation, prevention of renal failure and aggressive correction of thrombocytopenia may help to lower the risk of intracranial hemorrhage in adults on extracorporeal membrane oxygenator support.

Pathological complications of non-survivors of newborn extracorporeal membrane oxygenation

The pathology was reviewed of the early deaths identified from the first 50 neonates treated with extracorporeal membrane oxygenation (ECMO) during its introduction to the UK. Fifteen neonates died during or shortly after ECMO between August 1989 and June 1992. Data on 12 are presented (three did not have a postmortem examination). The clinical diagnoses at referral for ECMO were as follows: persistent pulmonary hypertension of the newborn (six infants), primary congenital pneumonia (one infant), community acquired pneumonia (two infants), birth asphyxia (one infant), respiratory distress syndrome (one infant), and meconium aspiration syndrome (one infant). In our group, at necropsy, five had significant haemorrhage (three intracranial, one pulmonary, one pericardial and intraventricular). Three of five infants with evidence of haemorrhage also had signs of sepsis. Six infants had evidence at necropsy of systemic sepsis, five showed evidence of severe anoxic brain injury, and four infants had cerebellar haemorrhages. Three infants had evidence of myocardial ischaemia. It is difficult to discriminate between the relative influence of the primary diagnosis, the mode of treatment, and the severity of presentation in the genesis of this pathology. It is likely that the extent and severity of some of the findings represent a pathological progression that would have been interrupted by the death of the patient, had ECMO not been instituted.