There has,
to da
te, been no prospec
tive descrip
tion of
the frequency wi
th which police officers encoun
ter individuals who display signs of exci
ted delirium syndrome (ExDS). The abili
ty
to documen
t the rela
tionship be
tween signs of exci
ted delirium and subjec
t ou
tcomes and
then de
termine
the underlying pa
thophysiology
tha
t resul
ts in morbidi
ty and mor
tali
ty is necessary in order
to de
termine
the case defini
tion for ExDS in live individuals. We prospec
tively evalua
ted
the frequency of signs of ExDS in a cohor
t of consecu
tive subjec
ts undergoing use of force by law enforcemen
t officers (LEOs) and de
termined
the frequency wi
th which
those fea
tures were encoun
tered alone and in combina
tion. Da
ta were collec
ted prospec
tively for all subjec
ts undergoing use of force (UOF) by LEOs in a single police agency from Augus
t 2006 un
til Augus
t 2009. Ten previously published signs of ExDS were prospec
tively recorded by officers: pain
tolerance, cons
tan
t/near cons
tan
t physical ac
tivi
ty, no
t responding
to police presence, superhuman s
treng
th, rapid brea
thing, no
t tiring despi
te heavy physical exer
tion, naked/inappropria
tely clo
thed, swea
ting profusely, ho
t to
the
touch, and a
ttrac
tion
to/des
truc
tion of glass/reflec
tive surfaces. UOF occurred in 1269 of 1.56 million police-public in
terac
tions (0.08 % , 95 % CI 0.08, 0.086). Of subjec
ts undergoing police use of force, 1101/1269 or 86.8 % (95 % CI 84.8 % , 88.6 % ) were assessed as having effec
ts of emo
tional dis
turbance, drugs, alcohol or a combina
tion of
these comorbidi
ties a
t the scene a
t the
time of
the UOF and 837/1269 or 66 % (95 % CI 63.3, 68.6) were violen
t a
t the
time of
the UOF. Excluding violence, 655/1269 (51.6 % 95 % CI 48.8, 54.4) had no signs of ExDS a
t the
time of UOF and ano
ther 405/1269 (31.9 % 95 % CI 29.4, 34.6 % )) had only one or
two signs of ExDS a
t the
time of UOF. The remaining 209/1269 (16.5 % , 95 % CI 14.5, 18.6) had 3 or more concomi
tan
t signs of ExDS a
t the
time of UOF. One person died in our cohor
t who was experiencing 10 concomi
tan
t fea
tures of ExDS a
t the
time of
the UOF even
t. Wi
th only one dea
th in our 3 year prospec
tive cohor
t, we canno
t commen
t on causali
ty or correla
tion be
tween number of Exci
ted Delirium signs and mor
tali
ty. Fur
ther s
tudy mus
t be under
taken
to de
termine whe
ther correla
tion exis
ts be
tween higher numbers of ExDS signs and physiologic measures of acu
te underlying pa
thology in live subjec
ts.
Conclusions
Law enforcement officers and other prehospital care providers can recognize and describe symptoms of ExDS in the field at the time of interaction. Even though police use of force is rare over 15 % , or approximately 1 in 6, of individuals undergoing police UoF have 3 or more concomitant signs of Excited Delirium at the time of the UoF event. The single death in our cohort occurred in an individual with 10 concomitant signs of ExDS. Future work including further clinical outcome data will determine whether higher numbers of concomitant signs of ExDS predicts subject morbidity or mortality and whether any specific symptoms or symptom cluster is associated with death. If so, a case definition will be able to be fully described.