The Jena Method: Perfusionist Independent, Standby Wet-Primed Extracorporeal Membrane Oxygenation (ECMO) Circuit for Immediate Catheterization Laboratory and/or Hybrid Operating Room Deployment

Background: The timely initiation of extracorporeal membrane oxygenation (ECMO) is crucial for providing life support. However, delays can occur when perfusionists are not readily available. The Jena Method aims to address this issue by offering a wet-primed ECMO system that can be rapidly established without the perfusionist's presence. Methods: The goal was to ensure prompt ECMO initiation while maintaining patient safety. The method focuses on meeting hygienic standards, safe primed storage of the circuit, staff training, and providing clear step-by-step instructions for the ECMO unit. Results: Since implementing the Jena Method in 2015, 306 patients received VA-ECMO treatment. Bacterial tests confirmed the sterility of the primed ECMO circuits during a 14-day period. The functionality of all the components of the primed ECMO circuit after 14 days, especially the pump and oxygenator, were thoroughly checked and no malfunction was found to this day. To train staff for independent ECMO initiation, a step-by-step system involves safely bringing the ECMO unit to the intervention site and establishing all connections. This includes powering up, managing recirculation, de-airing the system, and preparing it for cannula connection. A self-developed picture-based guide assists in this process. New staff members learn from colleagues and receive quarterly training sessions by perfusionists. After ECMO deployment, the perfusionist provides a new primed system for a potential next patient. Conclusions: Establishing a permanently wet-primed on-demand extracorporeal life support circuit without direct perfusionist support is feasible and safe. The Jena Method enables rapid ECMO deployment and has the potential to be adopted in emergency departments as well.

Sterility and performance of open and closed extracorporeal circuits after long-term dry-wet setups

BACKGROUND

The timeframe for safely using previously setup dry, crystalloid, and blood-primed extracorporeal circuits has long been debated. This study was undertaken to determine a safe deviation from standardized recommendations.

METHODS

Open (cardiopulmonary bypass) circuits and closed extracorporeal membrane oxygenation circuits were setup dry for up to 60 days and wet primed for up to 6 weeks with one control inoculated with Escherichia coli. Open circuits were cultured daily, closed circuits weekly. Circuits were primed with blood, albumin, heparin, NaHCO₃, and CaCl₂. Baseline pCO₂, pO₂, hemoglobin, lactate dehydrogenase, and plasma free hemoglobin were measured. Circuits were recirculated at a blood flow of 6 Liters/minute with a sweep gas of 1 Liter/minute at 100% FiO₂ for 1 minute. Post oxygenator blood gases were collected at 8-, 16-, and 24-hour intervals.

RESULTS

There was no observed compromise to the sterility of the circuits and no clinically significant gas exchange abnormalities observed over the duration of the study period. Statistical significance (p < 0.01) was seen in free hemoglobin and lactate dehydrogenase levels, most significant in between the 16- and 24-hour time point in the closed systems intentionally inoculated with E. coli.

CONCLUSION

Open and closed circuits can be safely setup dry for up to 60 days. Open, wet-primed circuits can be used safely up to 5 days. Closed, wet-primed circuits can be used safely up to 6 weeks. Blood-primed circuits can be safely run up to 16 hours prior to patient use but should be validated in a randomized clinical study.

Sterility Duration of Preprimed Extracorporeal Membrane Oxygenation Circuits

OBJECTIVES

There is a lack of standardization and supporting data regarding the duration preassembled and preprimed extracorporeal membrane oxygenation (ECMO) circuits are expected to be sterile. Therefore, the purpose of this study was to prospectively evaluate whether preassembled and preprimed ECMO circuits could maintain sterility for a period up to 65 days.

DESIGN

Four ECMO circuits (2 neonatal/pediatric¼" and 2 adolescent/adult ⅜ ") were assembled and primed under sterile conditions and maintained at room temperature. Culture samples were obtained from each circuit and plated within 1 hour. Culture samples were obtained on day 0 when assembled and primed then every 5 days up to day 65. Samples were plated on several different media including the following: blood agar plate: trypticase soy agar with 5% sheep blood, MacConkey agar, and thioglycollate broth then incubated at 35°C for 3 days.

RESULTS

All cultures obtained from the priming solution from of the¼" and ⅜ " ECMO circuits produced no microbial or fungal growth for the 65-day study period.

CONCLUSION

These pilot data suggest preprimed ECMO circuits may maintain sterility for a period up to 65 days. Additional studies evaluating a larger number of ECMO circuits are needed to confirm these findings.

Current and future status of extracorporeal life support for respiratory failure in adults

PURPOSE OF REVIEW

The purpose is to review the development and current application of extracorporeal life support [ECLS, extracorporeal membrane oxygenation (ECMO)] in acute severe respiratory failure.

RECENT FINDINGS

Extracorporeal support (ECMO) is used for acute severe respiratory failure in advanced ICUs. The current survival rate is 60-70%. Three controlled trials all demonstrated 20-30% improvement in survival compared to conventional care. Patients may now be maintained awake and ambulatory with spontaneous breathing.

SUMMARY

ECMO is the next step in the algorithm for management of severe respiratory failure unresponsive to conventional care.