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ECMO has even been shown to be used as a treatment to recovery to avoid lung transplantation . There are multiple reports of patients recovering after ECMO when the lung has been given time to repair . De Walue et al . did a retrospective study [ 22 ] looking at the maximum amount of time under VV ECMO where pulmonary recovery remains possible . 14 patients who were on VV ECMO for more than 50 days with COVID-19 and very severe ARDS were included in the study . Recovery was reported in 10 patients , with one patient on ECMO for 151 days , deeming this a good treatment and avoiding lung transplantation . Unnecessary transplants could thus be avoided in at least some patients with acute respiratory failure .
Currently , research is being done to develop treatments to enhance lung regeneration and repair . Managing the inflammatory response and infection of pathogens seems to be key to these improvements [ 23 ]. Stem cell therapy is also emerging , where endogenous lung progenitors , induced pluripotent stem cells , and embryonic cells may be the way forward in introducing truly regenerative lung cells for the future [ 24 ].
Intraoperative support Anesthesia support
Anesthesia management for lung transplants with venoarterial extracorporeal membrane oxygenation ( VA ECMO ) involves careful coordination between the anesthesia team , the transplant surgeons , and the ECMO specialists .
A preoperative evaluation of the patient ’ s medical history including the indication for transplant as well as a physical examination is carried out . A careful review of laboratory parameters such as full blood count , coagulation profile , metabolic profile as well inflammatory markers , echocardiogram , CT scan , and right heart catheterisation measurements is done . An anesthetic plan is made in discussion with the surgeon as well as the perfusionist . Anesthetic induction is carried out in a gentle manner minimizing hemodynamic fluctuations and keeping in mind the degree of pulmonary hypertension and right ventricular function . Continuous monitoring of arterial blood pressure , central venous pressure , cardiac output , and cerebral oximetry along with arterial blood gases and electrolytes form the corner stone of anesthetic management . Close coordination with the perfusionist is key to managing anticoagulation on ECMO . A fine balance must be kept in mind to balance the risk of clot in the circuit versus excessive bleeding and thromboelastography or thromboelastometry may be used as a guidance .
The ventilation strategy may vary depending on the patient ’ s lung condition and the phase of the transplant procedure . Lung protective ventilation strategies are typically employed to minimize ventilator-associated lung injury . Following the procedure , continuous monitoring in the intensive care unit ( ICU ) with close collaboration between the anesthesia team , transplant surgeons , and critical care specialists is done where management of pain , sedation , and ventilatory support in the postoperative period is looked at . Gradual weaning of ECMO support based on the patient ’ s clinical status and lung function is the goal .
Utmost vigilance is called for to avoid and address promptly complications such as bleeding , thrombosis , and hemolysis associated with ECMO . Overall , anesthesia management for lung transplant with VA ECMO requires a multidisciplinary approach , with close communication and coordination among all members of the healthcare team to optimize patient outcomes [ 25 – 27 ].
Intraoperative ECMO
ECMO plays a crucial role in LTx by providing temporary cardiopulmonary support intraoperatively . The use of VA ECMO intraoperatively mitigates the need for full cardiopulmonary bypass and thereby avoids all potential complications of cardiopulmonary bypass , such as less activation of coagulation cascade , thrombocytopenia and systemic inflammatory response syndrome leading to severe vasodilatory shock . The use of ECMO during LTx still presents potential challenges , including the risk of bleeding , thrombosis , infection , and organ dysfunction . These risks highlight the importance of careful monitoring and specialized care throughout the surgical procedure to mitigate complications . Despite these challenges , studies have shown that ECMO support during LTx can yield favourable outcomes .
Lus et al . emphasized the significant improvements in perioperative cardiopulmonary support for LTx through the use of extracorporeal life support ( ECLS ). Enhanced patient management , multidisciplinary collaboration , and standardized ECLS protocols have contributed to excellent outcomes in high-volume transplant centres . Although ECMO supported patients may experience a higher prevalence of complications , there may be no significant difference in long-term graft function compared to non-supported patients . It is worth noting that the evidence supporting ECLS in LTx is primarily based on realworld experience rather than randomized controlled trials [ 28 ].
The outcomes of LTx with and without ECMO were examined in a study involving 48 lung transplants . While the 30-day mortality rate was higher in patients with ECMO , the difference was not statistically significant . The study highlighted a successful ECMO weaning rate and indicated that ECMO was an effective adjunctive support during surgery for critically ill lung transplant recipients [ 29 ].
Routine intraoperative ECMO has shown promise in improving primary graft function and mid-term outcomes in bilateral LTx , as demonstrated by Hoetzenecker et al . [ 30 ]. Patients who underwent bilateral LTx with ECMO support exhibited low rates of primary graft dysfunction , favourable extubation times , and survival rates . These findings support the recommendation for routine intraoperative ECMO in bilateral LTx to enhance patient outcomes [ 31 ].
Intraoperative extracorporeal assistance in lung transplant has also been reviewed by Ruszel et al ., focusing on 77 lung transplant cases . The study highlighted that central ECMO had higher survival rates compared to peripheral ECMO or cardiopulmonary bypass ( CPB ). However , patients with support devices were more prone to acute kidney injury and thromboembolic complications . The study recommended the preference of central ECMO over peripheral cannulation or CPB during LTx [ 32 ].