The Impact and Statistical Analysis of a Multifaceted Anticoagulation Strategy in Children Supported on ECMO: Performance and Pitfalls.

BACKGROUND: We sought to determine whether the introduction of a new anticoagulation protocol improved the frequency with which target anticoagulation parameters were met in children supported with extracorporeal membrane oxygenation (ECMO). Additionally, we sought to correlate the results of various tests of anticoagulation with the heparin infusion dose (HID) for patients on ECMO and to evaluate the utility of these anticoagulation monitoring tests for the titration of the HID. METHODS: A retrospective chart review of 18 patients who received ECMO at an academic tertiary care children's hospital. Nine patients who were managed using a new anticoagulation protocol were matched by age and diagnosis with 9 patients managed with the old protocol. We collected data relating to patient demographics, type of extracorporeal support, disease process, and incidence of bleeding or thrombosis. Anticoagulation parameters collected include the activated clotting time (ACT), activated partial thromboplastin time (aPTT), prothrombin time/international normalized ratio, anti-factor Xa level, and antithrombin 3 level along with the HID at each time point. Patient groups were compared using a Generalized Linear Mixed Model, a mixed model analysis of variance, and correlational studies. MAIN RESULTS: The percentage of in-range ACT values was not different between the 2 protocols, whereas the percentage of in-range aPTT values was higher in the new anticoagulation protocol (ACT: 37.7% vs 39.5%; aPTT: 25.1% vs 39.8%). After accounting for repeated and variable measures within patients, the probability of obtaining an in-range ACT and aPTT did not differ significantly between the 2 protocols (ACT: P = .3488; aPTT: P = .16). The mean HID did not differ between the 2 groups (35.0 unit/kg/h vs 37.6 unit/kg/h, P = .56). Correlation coefficients demonstrated a significant inverse correlation between the ACT and the HID in both the groups (old: r = -.22, P < .0001; new: r = -.26, P < .0001). We observed a significant positive correlation between the aPTT and the HID in the historical group (r = .25, P < .0001), but no correlation between the aPTT and the HID in the current group (r = -.02, P = .71). The anti-factor Xa level showed a significantly positive correlation with the HID in the current group (r = .62, P < .0001). CONCLUSIONS: A multipronged monitoring regimen slightly increased the amount of time that anticoagulation parameters were within range. Correlations between the HID and the aPTT differed based on anticoagulation protocol, with a positive correlation in the older protocol and no correlation in the new protocol. This may highlight a problem in study design and analysis that requires further examination. Further trials are needed to assess the most useful markers with which anticoagulation protocols for ECMO can be created, adjusted, and evaluated.

Nosocomial Bloodstream Infections in Patients Receiving Extracorporeal Life Support: Variability in Prevention Practices: A Survey of the Extracorporeal Life Support Organization Members.

Nosocomial blood stream infections (BSIs) increase both the morbidity and the mortality of patients receiving extracorporeal life support (ECLS). The aim of this study was to identify common practices for blood stream infection prevention among national Extracorporeal Membrane Oxygenation (ECMO) programs. An electronic survey that comprised of a 16-item questionnaire was sent out to all ECMO program directors and coordinators within the United States that are part of the Extracorporeal Life Support Organization (ELSO) registry. A total of 152 institutions in 40 states were surveyed, with 85 (55%) responses. One-quarter of the institutions responded that an ECMO infection-prevention bundle or checklist was used during the cannulation. Less than half responded that an ECMO infection-prevention bundle or checklist was used for cannula maintenance, although a majority (82.9%) of institutions responded that a "standard approach to cannula dressings" was used. Half of the respondents reported antimicrobial prophylaxis was routinely prescribed for patients on ECMO, although specific regimens varied widely. Of the institutions, 34.2% reported sending daily blood cultures as part of routine surveillance. Smaller programs were more likely to send daily surveillance blood cultures (58.8%, P < .01). We found no clear consensus on practices used to prevent BSI in patients receiving ECMO.

An Updated Therapeutic Intervention Scoring System for Critically Ill Children Enables Nursing Workload Assessment With Insight Into Potential Untoward Events.

BACKGROUND: To introduce an updated version of the original Therapeutic Intervention Scoring System (TISS) applicable to critically ill children (TISS-C). This version was designed to assess patient acuity and nursing workload (NW) and to determine a relationship between such assessment and the incidence of adverse events. METHODS: Reviewing previous versions of TISS, an updated TISS-C was developed. Items inapplicable to pediatric critical care were eliminated; items current to critical care were added; and items still valid were edited. The point system accounts for the wide range of care provided. Random patients from a predetermined period had TISS-C scores calculated. The TISS-C scores were also calculated on patients with documented adverse events. Baseline scores were compared with scores of patients in whom adverse events had occurred. We determined the pediatric intensive care unit (PICU) NW to be the product of the TISS-C score and the patient-nurse ratio (PNR). RESULTS: One hundred twenty-five random patients had a mean TISS-C of 14.6 ± 11.8. Patients with any adverse event (98) had a TISS-C of 19.9 ± 11.6 (P < .05). Using our PICU mean PNR of 1.4 (20 patients/14 nurses), the NW for patients with more severe events was 33.6 ± 15.9. CONCLUSIONS: Critically ill pediatric patients are more vulnerable to experience adverse events when their derived NW values are high. It is postulated that a critical NW exists, where adverse events are more likely to occur.

Risk factors associated with intracranial hemorrhage in neonates with persistent pulmonary hypertension on ECMO.

BACKGROUND: Up to 40% of infants with persistent pulmonary hypertension (PPHN) remains refractory to conventional therapies, and extracorporeal membrane oxygenation (ECMO) is offered as an effective support for this group. However, ECMO is a highly invasive and risky procedure with devastating complications such as intracranial hemorrhage (ICH). In this study, we aimed to determine the risk factors for ICH in infants with PPHN. METHODS: A case-control study of patients admitted to the pediatric intensive care unit (PICU) with PPHN requiring ECMO support was conducted. The study was carried out at a 25-bed PICU in large urban tertiary care children's hospital. A total number of 32 subjects were studied. Patients with and without ICH during ECMO were evaluated for activated clotting time (ACT), heparin dosing, platelet count, coagulation profile such as activated partial thromboplastin time (aPTT), prothrombin time (PT), international normalized ratio (INR), fibrinogen level, vital signs including heart rate and mean arterial pressure (MAP), transfusion history, gestational age, and severity of pre-ECMO illness as possible risk factors. RESULTS: Low fibrinogen level (115 ± 13 mg/dl) and low platelet counts (37.4 ± 18.3 Thousand/µl) were associated with higher incidence of ICH (p = 0.009 and p = 0.005, respectively). Elevated MAP (69 ± 4.34 mmHg) was also noticed in ICH patients (p = 0.006). CONCLUSIONS: Results demonstrated that low fibrinogen level and low platelet count were associated with ICH in PPHN patients on ECMO. While on ECMO support, maintaining fibrinogen and platelet counts within normal ranges seems crucial to prevent ICH in PPHN patients. This is the first report identifying low fibrinogen level among the risk factors for ICH in infants with PPHN on ECMO support.