Acoustic Communication for Medical Nanorobots

Communication among microscopic robots (nanorobots) can coordinate their activities for biomedical tasks. The feasibility of in vivo ultrasonic communication is evaluated for micron-size robots broadcasting into various types of tissues. Frequencies between 10MHz and 300MHz give the best tradeoff between efficient acoustic generation and attenuation for communication over distances of about 100 microns. Based on these results, we find power available from ambient oxygen and glucose in the bloodstream can readily support communication rates of about 10,000 bits/second between micron-sized robots. We discuss techniques, such as directional acoustic beams, that can increase this rate. The acoustic pressure fields enabling this communication are unlikely to damage nearby tissue, and short bursts at considerably higher power could be of therapeutic use.Comment: added discussion of communication channel capacity in section

Reduction in coronary artery bypass grafting surgery mortality and morbidity during a 3-year multicenter quality improvement project.

OBJECTIVE: Risk-adjusted operative mortality is a key quality measure for isolated coronary artery bypass grafting. Through a multicenter quality improvement initiative, we sought to improve this measure at 14 surgical programs within a large and geographically dispersed health care system. METHODS: Observed mortality and combined mortality/morbidity rates for isolated coronary artery bypass grafting were collected from January 2014 to June 2017. Expected mortality and mortality/morbidity rates were determined using the Society of Thoracic Surgeons risk models. The observed/expected ratios during the baseline (2014) and final 12-month outcome period were compared. The quality improvement intervention was multifaceted and surgeon led, and consisted of (1) regular sharing of unblinded data, (2) standardized quality improvement processes, (3) regular system-wide quality improvement meetings, (4) annual observed/expected mortality targets, (5) identification of underperforming institutions and creation of nonpunitive quality improvement action plans, and (6) implementation of checklists to drive perioperative care standardization. RESULTS: The observed/expected ratio of mortality was 1.19 during the baseline period and decreased to 0.59 for the outcome period (P = .004) without a change in expected mortality or case volume. The observed/expected ratio decreased for mortality/morbidity, and mortality without antecedent morbidity was almost eliminated. CONCLUSIONS: A significant and clinically meaningful 50% reduction in the observed/expected ratio for isolated coronary artery bypass grafting mortality was observed during a multifaceted quality improvement initiative across a large multicenter health care system. Morbidity also decreased. Keys to success included surgeon leadership and engagement, frequent unblinded data sharing, development of standardized quality improvement processes, improvement and standardization of care delivery, setting of quality improvement targets, and a shared vision for improved patient outcomes