Outcomes with use of extra-corporeal membrane oxygenation in high-risk pulmonary embolism: a national database perspective

Case Report: Resuscitation of patient with tumor-induced acute pulmonary embolism by venoarterial extracorporeal membrane oxygenation

Background

Pulmonary embolism is a condition of right cardiac dysfunction due to pulmonary circulation obstruction. Malignant tumor-induced pulmonary embolism, which has a poor therapeutic outcome and a significant impact on hemodynamics, is the cause of sudden death in patients with malignant tumors.

Case description

A 38-year-old female patient, who had a medical history of right renal hamartoma, and right renal space-occupying lesion, was admitted to the hospital. During the procedure to resect the right renal malignancy, the blood pressure and end-tidal carbon dioxide level dropped, and a potential pulmonary embolism was considered as a possibility. After inferior vena cava embolectomy, the hemodynamics in the patient remained unstable. The successful establishment of venoarterial extracorporeal membrane oxygenation (VA-ECMO) resulted in the stabilization of her hemodynamics and ventilation. On Day 2 of VA-ECMO support, her respiration and hemodynamics were relatively stable, and ECMO assistance was successfully terminated following the "pump-controlled retrograde trial off (PCRTO)" test on Day 6. The patient improved gradually after the procedure and was discharged from the hospital after 22 days.

Conclusion

VA-ECMO can be used as a transitional resuscitation technique for patients with massive pulmonary embolism. It is critical for the perfusion of vital organs and can assist with surgical or interventional treatment, lower right heart pressure, and hemodynamic stability. VA-ECMO has a significant impact on patient prognosis and can reduce the mortality rate.

Extracorporeal Membrane Oxygenation for Pulmonary Embolism: A Systematic Review and Meta-Analysis

BACKGROUND

The use of extracorporeal membrane oxygenation (ECMO) for high-risk pulmonary embolism (HRPE) with haemodynamic instability or profound cardiogenic shock has been reported. Guidelines currently support the use of ECMO only in patients with cardiac arrest or circulatory collapse and in conjunction with other curative therapies. We aimed to characterise the mortality of adults with HRPE treated with ECMO, identify factors associated with mortality, and compare different adjunct curative therapies.

METHODS

We conducted a systematic review and meta-analysis, searching four international databases from their inception until 25 June 2023 for studies reporting on more than five patients receiving ECMO for HRPE. Random-effects meta-analyses were conducted. The primary outcome was in-hospital mortality. A subgroup analysis investigating the outcomes with curative treatment for HRPE was also performed. The intra-study risk of bias and the certainty of evidence were also assessed. This study was registered with PROSPERO (CRD42022297518).

RESULTS

A total of 39 observational studies involving 6409 patients receiving ECMO for HRPE were included in the meta-analysis. The pooled mortality was 42.8% (95% confidence interval [CI]: 37.2% to 48.7%, moderate certainty). Patients treated with ECMO and catheter-directed therapy (28.6%) had significantly lower mortality (p < 0.0001) compared to those treated with ECMO and systemic thrombolysis (57.0%). Cardiac arrest prior to ECMO initiation (regression coefficient [B]: 1.77, 95%-CI: 0.29 to 3.25, p = 0.018) and pre-ECMO heart rate (B: -0.076, 95%-CI: -0.12 to 0.035, p = 0.0003) were significantly associated with mortality. The pooled risk ratio when comparing mortality between patients on ECMO and those not on ECMO was 1.51 (95%-CI: 1.07 to 2.14, p < 0.01) in favour of ECMO. The pooled mortality was 55.2% (95%-CI: 47.7% to 62.6%), using trim-and-fill analysis to account for the significant publication bias.

CONCLUSIONS

More than 50% of patients receiving ECMO for HRPE survive. While outcomes may vary based on the curative therapy used, early ECMO should be considered as a stabilising measure when treating patients with HRPE. Patients treated concurrently with systemic thrombolysis have higher mortality than those receiving ECMO alone or with other curative therapies, particularly catheter-directed therapies. Further studies are required to explore ECMO vs. non-ECMO therapies in view of currently heterogenous datasets.

Mental Health and Quality of Life in Pulmonary Embolism: A Literature Review

Pulmonary embolismis an acute disease with chronic complications and, although it is not considered a chronic disease, it requires close follow-up. The scope of the present literature review is to decode the existing data concerning quality of life and the mental health impact of PE during the acute and long-term phases of the disease. The majority of studies reported impaired quality of life in patients with PE when compared to population norms, both in the acute phase and >3 months after PE. Quality of life improves over time, irrespectively of the measurement used. Fear of recurrences, elderly, stroke, obesity, cancer and cardiovascular comorbidities are independently associated with worse QoL at follow-up. Although disease specific instruments exist (e.g., the Pulmonary Embolism Quality of Life questionnaire), further research is required in order to develop questionnaires that may fulfil international guideline requirements. The fear of recurrences and the development of chronic symptoms, such as dyspnea or functional limitations, may further impair the mental health burden of PE patients. Mental health may be implicated by post-traumatic stress disorder, anxiety and depressive symptoms present following the acute event. Anxiety may persist for 2 years following diagnosis and may be exaggerated by persistent dyspnea and functional limitations. Younger patients are at higher risk of anxiety and trauma symptoms while elderly patients and patients with previous cardiopulmonary disease, cancer, obesity or persistent symptoms exhibit more frequently impaired QoL. The optimal strategy for the assessment of mental health in this patient pool is not well defined in the literature. Despite mental burden being common following a PE event, current guidelines have not incorporated the assessment or management of mental health issues. Further studies are warranted to longitudinally assess the psychological burden and elucidate the optimal follow-up approach.