John, Shobana Rajan, Alana Flexman, and Tumul Chowdhury are strong starting contacts for English-language neuroanesthesia outreach. Below is a verified shortlist, primarily from the US, Canada, and UK.

There is no authoritative ranking of “most prominent” or “most active.” I selected these physicians based on academic leadership, education, and documented social-media involvement; I could not verify comparative posting frequency.

Name / location	Why consider them	Public professional email	Public professional phone	Social media
Shobana Rajan, MD — Cleveland Clinic, USA	Neuroanesthesiology fellowship director; documented role as social-media editor of the Journal of Neurosurgical Anesthesiology.	RAJANS5@ccf.org	+1 216-598-6915 — fellowship contact	X: @shobanarajan51 · LinkedIn
Alana Flexman, MD — Vancouver, Canada	UBC neuroanesthesia division head; established professional presence on X.	alana.flexman@phc.ca	+1 604-816-7520 — published research contact	X: @AlanaFlex
Tumul Chowdhury, MD — UAB, Birmingham, USA	Professor, vice chair and clinical director of Neuroscience Anesthesiology. His listed interests include big data and AI models, making him particularly relevant to your AI conference.	tchowdhury@uabmc.edu	+1 205-934-6007 — department office	X: @ChowdhuryTumul
John F. Bebawy, MD — Northwestern, Chicago, USA	Professor of anesthesiology and neurological surgery; chief of Neuroanesthesia.	anesthesiology@northwestern.edu — department forwarding address	+1 312-695-0061 — clinical office	LinkedIn; activity level unverified.
Martin Smith — London, UK	Distinguished neuroanaesthesia educator and recipient of the NACCS Lifetime Achievement Award.	martin.smith@uclh.nhs.uk	+44 20 7829 8711 — neuroanaesthesia department	Personal social-media activity unverified.
Paul Garcia, MD, PhD — Columbia, New York, USA	Neuroanesthesia division chief; elected SNACC secretary-treasurer in 2026.	pg2618@cumc.columbia.edu	+1 212-305-2179 — department office	Personal social-media activity unverified.

For your AI in Neuroanesthesiology webcast, I would contact Tumul Chowdhury first for the AI topic, Shobana Rajan for education and online outreach, and Alana Flexman for academic networking. These are my recommendations based on the evidence above. All contact details are publicly listed professional contacts; departmental numbers and forwarding emails are labeled.