NT can safely be performed by paramedics in an EMS system that includes urban, rural, and wilderness settings. Its efficacy does not differ between patients suffering from blunt versus penetrating trauma; however, it appears most beneficial for patients who are unstable but still have vital signs.

Introduction The summit of Yosemite's Half Dome is reached using cable handrails for the final 146 m (480 ft). Access to these cables was restricted to users with permits in 2010. The authors aim to describe the impact of permitting on search and rescue (SAR) in the region of the park most affected by permitting. Methods An observational study from 2005 to 2009 and 2011 to 2015 comparing the number of incidents, major incidents (exceeding $500), victims, and fatalities before and after permitting the use of cable handrails on Half Dome in the area above Little Yosemite Valley (LYV) and parkwide. Each year was analyzed separately with t tests and Mann-Whitney U tests. Data are presented as mean±SD. Result The number of hikers in the study area was reduced by up to 66% by permitting. Above LYV from 2005 to 2009, there were 85 SAR incidents, 134 victims, 8 fatalities, 38 major incidents, and annual SAR costs of $44,582±28,972. From 2011 to 2015, the same area saw 54 SAR incidents, 156 victims, 4 fatalities, 35 major incidents, and annual SAR costs of $27,027±19,586. No parameter showed statistical significance. Parkwide SAR incidents decreased from 232 to 198 annual incidents ( P=0.013) during the same time period, with parkwide mortality increasing from 8 to 12 deaths annually ( P=0.045). Conclusions SAR incidents, victims, fatalities, or costs above LYV did not decrease after cable handrail permitting. Parkwide SAR activity decreased during the same intervals. This strongly suggests that overcrowding is not the key factor influencing safety on Half Dome. This discordant trend warrants close observation over 5 to 10 y.

There was no significant difference in survival between patients with prolonged versus short transport times who underwent NT. Patients with prolonged transport times were more likely to have sustained blunt trauma, have vital signs on EMS arrival, and to have clinical improvement after NT.