Table 2. References regarding tracheotomy-related deaths associated with open surgical tracheostomy (OST) vs. percutaneous dilatational tracheostomy (PDT).

First author/comment	OST	PDT
Dulguerov 1999 (18) Meta-analysis OST versus PDT 1986–1996	17/10 000	55/10 000
Kearny 2000 (e72) Single center retrospective review PDT 1990–1998	n.s.	0.6%
Oliver 2007 (17) Meta-analysis OST versus PDT (1999–2006)	0.16%(1/628)	0.58%(3/522)
Kost 2005, 2008 (5, 6) Evaluation PDT versus OST 1988–2003	0–2%	0–0.5%
Mallick 2010 (20) Review tracheostomy in critically ill patients 1981–2008 (studies have demonstrated a procedural mortality rate approaching zero)	n.s.	n.a.
Dennis 2013 (e38) Single center retrospective review PDT 2001–2011	n.s.	0.16%
Simon 2013 (e101) Review PDT 1985–2013	n.s.	0.17%
Brass 2016 (8) Review PDT versus OST 1990–2011 (no evidence of a reduction in mortality with the use of a percutaneous technique)	n.s.	n.s.
Results of our review 1990–2015
Total	0.62% CI: [0.47; 0,82]	0.67% CI: [0,56; 0,81]
Deaths due to false passage	0.11% CI: [0.06; 0.22]	0.20% CI: [0.15; 0.29]
Deaths due to loss of airway	0.21% CI: [0.13; 0.34]	0.20% CI: [0.14; 0.28]
Deaths due to hemorrhage	0.26% CI: [0.17; 0.40]	0.26% CI: [0.19; 0.35]

CI, confidence interval; n.s., not specified