Journal of Extra-Corporeal Technology最新文献

Hematologic complications are a source of morbidity and mortality for patients receiving extracorporeal membrane oxygenation (ECMO) support. There is no consensus strategy for monitoring anticoagulation for children supported with ECMO. This study evaluated a novel measurement of anticoagulation for children on ECMO. This was a single-center observational study of children supported with ECMO from 2015 to 2020. Each patient's current unfractionated heparin dose was multiplied by the current antithrombin III (AT) level to obtain a novel anticoagulation value, the heparin-antithrombin product (HAP). This value was compared with the heparin dose, AT, and activated clotting time (ACT) to predict anti-Xa value using linear correlation and decision tree methods. Data were obtained from 128 patients supported with ECMO. The HAP value was more highly correlated with anti-Xa level than heparin dose, AT level, and ACT. This correlation was highest in the neonatal population (r = .7). The variable importance metrics from the regression tree and random forest models both identified the HAP value as the most influential predictor variable for anti-Xa value. The HAP value is more highly correlated with the anti-Xa level than heparin dose, AT level, or ACT. Further research is needed to evaluate the effectiveness of the HAP value as a measurement of anticoagulation for children on ECMO.

Laboratory testing is a helpful tool for clinicians, but can be costly and harmful to patients. A quality improvement project was initiated to reduce laboratory testing for patients receiving extracorporeal membrane oxygenation (ECMO) in a pediatric intensive care unit (PICU) at a tertiary care center. Preliminary data was gathered to demonstrate preimplementation practice, cost, and patient need for packed red blood cell (pRBC) transfusions. A new protocol was created by an interprofessional team based on best practice and benchmarking with high-performing organizations. The project was evaluated using two comparison groups, pre- and postimplementation for anyone receiving ECMO therapy in the PICU. The average laboratory tests per ECMO day decreased by 52% (128.4 vs. 61.1), cost per case decreased by 14.7%, pRBC transfusions decreased from 100% to 85%, length of stay (LOS) decreased by 8 days, and mortality rates decreased by 9.5%. The revised pediatric ECMO laboratory testing guidelines were successfully implemented and reduced laboratory cost without adverse effects on mortality rates or LOS.

Pediatric patients undergoing cardiopulmonary bypass (CPB) require adequate anticoagulation to combat hemostatic activation. Heparin is used to bind and catalyze antithrombin III (ATIII) that works to inhibit clot formation. To dose heparin, a weight-based (WB) or patient-specific concentration-based (PSCB) method can be used. The WB protocol calculates the dose based on the patients' weight and uses an activated clotting time (ACT) test to ensure anticoagulation. The ACT has limitations during CPB especially for pediatric patients who have immature hemostatic systems. The PSCB method predicts the patients' response to heparin by projecting a heparin dose-response (HDR) curve. Some investigators have found benefit to using the PSCB method but further investigation into how well the HDR predicts the heparin response is needed. A literature review was conducted for studies that looked at heparin management strategies in pediatric CPB patients between 1992 and 2020. Articles that focused on pediatric physiology, heparin management strategies, and anticoagulation were included. Articles older than 1990 were excluded. The literature review highlights that utilizing the PSCB approach more adequately anticoagulated patients. The WB protocol was found to have several flaws due to its reliance on the ACT, especially in infants. The results show that further investigation is needed to understand why there is benefit to using the PSCB approach. Observing the association between the HDR curve and subsequent heparin concentrations could determine how accurately it predicts the patients' response to heparin and why there is benefit to using this method.

Small increases in serum creatinine postoperatively reflect an acute kidney injury (AKI) that likely occurred during cardiopulmonary bypass (CPB). Maintaining adequate oxygen delivery (DO₂) during CPB, known as GDP (goal-directed perfusion), improves outcomes. Whether GDP improves outcomes of patients at high risk for acute renal failure (ARF) is unknown. Forty-seven adult patients undergoing cardiac surgery with CPB utilizing GDP with Cleveland Clinic Acute Renal Failure Score of 3 or greater were compared with a matched cohort of patients operated upon using a flow-directed strategy. CPB flow in the GDP cohort was based on a DO₂ goal of 260 mL/min/m². Serum creatinine values were used to determine whether postoperative AKI occurred according to AKIN (Acute Kidney Injury Network) guidelines. We examined the distribution of all variables using proportions for categorical variables and means (standard deviations) for continuous variables and compared treatment groups using t tests for categorical variables and tests for differences in distributions for continuous and count variables. We used inverse probability of treatment weighting to adjust for treatment selection bias. In adjusted models, GDP was not associated with a decrease in AKI (odds ratio [OR]: .97; confidence interval [CI]: .62, 1.52), but was associated with higher odds of ARF (OR: 3.13; CI: 1.26, 7.79), mortality (OR: 3.35; CI: 1.14, 9.89), intensive care unit readmission (OR: 2.59; CI: 1.31, 5.15), need for intraoperative red blood cell transfusion (OR: 2.02; CI: 1.26, 3.25), and postoperative platelet transfusion (OR: 1.78; CI: 1.05, 3.01) when compared with the historic cohort. In patients who are at high risk for postoperative renal failure, GDP was not associated with a decrease in AKI when compared to the historical cohort managed traditionally by determining CPB flows based on body surface area. Surprisingly, the GDP cohort performed significantly worse than the retrospective control group in terms of ARF, mortality, intensive care unit readmission, and RBC and platelet transfusions.

Blood hemolysis caused by mechanical impact is a serious problem in medicine. In addition to the heart-lung machine (artificial surfaces, flow irritating connection points) which contributes to hemolysis, blood suction and surgical suction devices are influencing factors. Goal of our research is to develop best flow optimizing suction geometry that represents the best compromise between all influencing effects. Based on data that negative pressure and turbulence have a negative impact on blood components, 27 surgical suction tips have been examined for acoustic stress and negative pressure behavior. Furthermore, a dimensionless factor Q was introduced to assess the overall performance of the suction tips investigated.

Near-infrared spectroscopy (NIRS) is a non-invasive clinical tool allowing for real-time, continuous measurement of regional tissue oxygenation (rSO₂); though predominantly used for neuromonitoring, it also has the potential for early detection of hemodynamic compromise in the patients on extracorporeal life support (ECLS). The authors present two cases of neonates for whom continuous monitoring of multisite rSO₂ with NIRS provided the first indication of a significant compromise in hemodynamic status from catastrophic hemorrhagic complications while on ECLS ahead of conventional ECLS monitoring parameters. Routine NIRS monitoring of neonates on ECLS has utility for ongoing assessment of hemodynamic status and can be used for early detection of complications leading to impaired tissue perfusion.

Standards and guidelines for cardiopulmonary bypass have been established by various professional societies. They serve as an instrument to guide safe and effective patient care. We conducted a survey of practicing perfusionists in Kenya to learn about their background, education, current clinical practice and about their knowledge, and attitude regarding standards and guidelines. Two multiple-choice surveys were distributed to all known practicing perfusionist in Kenya using SurveyMonkey (San Mateo, CA). Multiple-choice questions related to professional background, training, annual procedure volume, staffing models, clinical practices, the use of safety devices, and the use of checklists were included in the questionnaires. The survey also inquired about familiarity with American and European perfusion practice standards and guidelines and opinions on establishing standards in Kenya. Responses were received from 12 perfusionists practicing at 10 centers. Professional backgrounds included anesthesia nursing, clinical officers, and critical care nursing. Sixty-seven percent (8/12) received formal training and 33% (4/12) trained primarily through clinical instruction. Of those that received formal training, 63% (5/8) received 1-2 years of training, 25% (2/8) <1 year but more than 6 months, and 12.5% (1/8) received 6 months of formal training. The median clinical experience was 5 years (range 1-22). The median annual case load was 54 (range 0-100). Use of safety devices was reported as follows: level sensor 75% (9/12), air bubble detector 17% (2/12), one-way vent valves 67% (8/12), continuous venous oxygen saturation monitoring 25% (3/12), and gas supply analyzers 33% (4/12). More than one-third of the respondents had no knowledge of the American and European perfusion practice standards, and nearly two-thirds were aware of or had read them. This survey provides contextual information about perfusion practice in Kenya in 2021. There was consensus among perfusionists to develop standards and practice guidelines for Kenya.