We often talk about ECMO in terms of circulatory or respiratory support. A more obscure field is ECMO supporting airway management. ECMO could provide respiratory support in a patient with a failed emergency airway or during entire airway surgeries. Here are two papers worth reading. Hong et al, from a recent issue of Journal of Critical Care describes using ECMO for ventilatory support in airway surgery where conventional mangement was impossible. The other, by Willms et al in Respiratory Care 2012, is a review of reported cases where patients were put on ECMO for emergent airway obstructions.
Hong et al.
In a recent issue of Journal of Critical Care, Hong et al retrospectively review 18 patients who were due to have surgery for central airway obstructions. These obstructions were mostly bronchogenic carcinomas or direct airway extension of adjacent tumours. In order to safely perform the surgery these patient’s airway needed to be secured.
However, based on pre-operative MR or bronchoscopy, in these patients conventional airway management was deemed impossible or too risky given the risk of complications and total obstruction. Instead, they put the patients on veno-venous ECMO for bridging ventilatory support while surgery was ongoing. The patients were on ECMO while the airway mass was removed through bronchoscopy and a patent airway was achieved.
Etiologies were mostly malignant tumours. Indications for VV-ECMO was tumour mass removal, tracheal stent insertions and failed stents, all of them via a rigid bronchoscope. Of the 18 cases only one was not successfully weaned from VV-ECMO. Median time on extracorporeal circulation was 22 hours. One patient died from massive airway haemorrhage, which the authors suggest could be related to the heparin anticoagulation the ECMO requires.
The authors conclude ECMO has a broader indication for ventilatory support in patients undergoing high risk airway surgery.
Study lives here:
J Crit Care. 2013 Oct;28(5):669-74. doi: 10.1016/j.jcrc.2013.05.020. Epub 2013 Jul 8. Use of venovenous extracorporeal membrane oxygenation in central airway obstruction to facilitate interventionsleading to definitive airway security. Hong Y, Jo KW, Lyu J, Huh JW, Hong SB, Jung SH, Kim JH, Choi CM.
Willms et al
The Willms paper is a primarily a case report. The patient had an osteogenic sarcoma with lung metastases. One tumour mass involved the distal trachea where the patient had stent to ensure patency. Then one day he was admitted with respiratory failure and had to be intubated. He was successfully intubated but there was marked resistance to inflation, suggesting there was an airway obstruction below the tube. ET-tube placement was confirmed by fiberoptics that also revealed how the growing tumour was obstructing the stent. Then patient became hypoxic, bradycardic and went into PEA cardiac arrest.
Here’s where ECMO saved this patients life. They cannulated the right femoral artery and vein and put the patient on VA-ECMO Immediately blood pressure, pulse and oxygenation stabilised at normal levels. Stabilisation on ECMO gave the ENT surgeons the hour they needed to remove the tumourous obstructing mass. The patient was weaned form ECMO the next day and survived the ordeal.
The paper then goes on to briefly review the other reported cases of severe airway obstructions saved by ECMO.
Paper lives here:
Respir Care. 2012 Apr;57(4):646-9. doi: 10.4187/respcare.01417. Emergency bedside extracorporeal membrane oxygenation for rescue of acute tracheal obstruction. Willms DC, Mendez R, Norman V, Chammas JH.
ECMO can provide airway support in instances where conventional airway management has failed or is inappropriate.