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Beecher et al. World Journal of Emergency Surgery 2015, 10:6
Open Access
Hospital tests and patient related factors
influencing time-to-theatre in 1000 cases of
suspected appendicitis: a cohort study
Suzanne Beecher*, Donal Peter O’Leary and Ray McLaughlin
Background: Acute appendicitis is increasingly being managed in the setting of a dedicated emergency theatre.
However understanding of hospital factors that influence time-to-theatre (TTT) is poor. Thus, the aim of this study is
to identify factors that influence TTT and to observe the effect of prolonged TTT on patient outcome.
Methods: A retrospective review of an electronic prospectively maintained database was performed over a 2 year
period. Factors thought to influence TTT were highlighted. A delay was defined as TTT >8 hours. Data analysis was
performed using SPSS 20.
Results: 1,000 cases of suspected acute appendicitis were identified. Median age was 19 years. Appendicectomy
was performed in 90.7%. 68.1% underwent laparoscopic appendicectomy. Overall mean TTT was 12 hours,
27 minutes. There was a significant association between delayed TTT and female gender (p = 0.017), older age
(p = 0.001), pre-operative radiology (<0.001), normal WCC (p < 0.001), normal neutrophils (p < 0.001) and histological
non-perforated appendix (p < 0.001). However, on multivariate analysis, younger age, a neutrophilia and presence of
a perforation had a shorter TTT. Delayed TTT did not affect outcome variables including post-operative collection
(3.59% v 4.38%, p = 0.528), readmission rate (6.54% v 5.72%, p = 0.403) and length of stay (3.1 days v 3.34 days,
p = 0.823).
Conclusions: This study highlights key hospital factors that influence TTT in patients with suspected appendicitis.
Identification of these influential factors adds greatly to our understanding of patient prioritisation. Finally, TTT
delays greater than 8 hour do not appear to affect short-term patient outcomes.
Keywords: Appendicitis, Delay, Time, Factors, Appendicectomy, Appendectomy, Outcome, Readmission, Complications
Acute appendicitis is recognised internationally as the
most common acute surgical emergency requiring surgical intervention [1]. Acute appendicitis is increasingly
being managed in the setting of a dedicated emergency
theatre [2,3]. Provision of dedicated emergency theatre
facilities has resulted in improved patient outcomes including a shorter length of stay and improved morbidity
and mortality rates [4,5].
There is much debate surrounding the timing of appendicectomy performance at present [6]. In order to
avoid out of hours appendicectomies being performed,
* Correspondence: [email protected]
Department of Surgery, Galway University Hospital/National University of
Ireland (NUI), Galway, Republic of Ireland
delays may be encountered [7]. Recent published data
has noted that delays up to 24 hours do not appear to
increase the complexity of appendicitis or associated
morbidity [8,9]. On this basis it appears delays less than
24 hours may not adversely affect patient outcome, however timely intervention is still warranted in specific
groups for control of sepsis and pain [10,11].
Provision of timely intervention is very much
dependent upon an efficient emergency theatre [12].
Despite having dedicated emergency theatres, delays are
still encountered on a daily basis between the time when
a decision is made to go to theatre and the time of intervention with costly implications [13]. A lack of capacity
to facilitate emergency cases for all surgical specialties
presumably is the main factor contributing to delays
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Beecher et al. World Journal of Emergency Surgery 2015, 10:6
however there is a paucity of information within the literature pertaining to the factors that influence the time
to theatre (TTT) in patients with suspected acute appendicitis. Identification of these factors would greatly enhance our understanding of TTT in suspected acute
appendicitis and aid the organisation of emergency surgery services.
Thus we wished to identify the hospital and patient related factors that influence TTT in patients with suspected appendicitis, paying particular attention to
patient, procedure and histological factors. We then
wished to examine the effect of delayed TTT on short
term patient outcomes following appendicectomy.
An electronic prospectively maintained emergency theatre database was used to identify patients with suspected appendicitis between 31st December 2011 to the
31st December 2013.
Data collected included patient gender, patient age, patient identification number, operation, time added to list,
operation start time and operation finish time. We also
noted the surgical approach used, either laparoscopic or
open. Blood parameters were recorded including White
Cell Count (WCC), neutrophils and C-reactive protein
(CRP). Use of additional radiological diagnostic modalities pre-operatively was recorded. Outcome variables
including length of stay, post-operative collection, conversion to open, readmission and perforation rates were
recorded. We did not gather data relating to wound infections as outpatient management of these complications would have provided incomplete and inaccurate
The time at which the patient was added to the emergency theatre list represented the time that the decision
was made to go to theatre at the time of surgical admission in the Emergency Depatment. A delayed time to
theatre for the operative management of acute appendicitis of >8 hours was defined by priority targets for
emergency theatre access in emergency surgery guidelines and publications. We thus defined a delayed appendicectomy as >8 hours following the decision to
intervene. Out of hours was defined as an operation
start time outside the hours of 9 am to 5 pm.
A univariate analysis was performed to identify factors
associated with a delayed TTT. Significant factors were
then entered into a multivariate analysis and analysed
using a logistic regression model to identify independent
factors which influenced TTT. Statistical analysis was
performed using SPSS version 20.0. A p-value <0.05
was considered statistically significant. Ethics approval
was received for the ethics committee at University
Hospital Galway.
Page 2 of 5
1000 cases of suspected acute appendicitis were identified from our prospectively maintained emergency theatre electronic database and we subsequently performed
a detailed analysis of these cases.
Patient demographics and operative details are outlined in Table 1. The median patient age was 19 years.
Of the 1000 patients who had clinical evidence of appendicitis, appendicectomies were performed in 90.7% of
patients, with the majority of patients (68.1%) undergoing laparoscopic appendicectomy. In patients who
were <12 years, open appendicectomy was more frequently performed (62.5%).
Of the 907 appendicectomies performed, pathology
was detected in 730 cases, providing a negative appendicectomy rate of 19.6%. Table 2 details the histopathology
findings on the resected appendixes. Acute appendicitis
was found in 65.5% specimens. 11.8% of patients had a
perforated appendix. A carcinoid tumour was detected
in 1%.
We next looked at factors influencing TTT, as
highlighted by Table 3. The overall mean time to theatre
was 12 hours, 27 minutes. A number of factors were
found to be significant on univariate analysis. Younger
patients were brought to theatre quicker than older patients (p = 0.001). Male patients endured a shorter time
awaiting surgery (p = 0.017). Patients with abnormal
blood parameters, particularly those with a raised neutrophil count on presentation, were also brought to theatre faster than those with normal parameters (p <
0.001). Those operated on within 8 hours were more
likely to have their appendix removed (P = 0.035).
Table 1 Patient demographics & operative details
N = 1000
Age* (range)
19 (2–78)
Total Patients ≤12 years
Females ≥16 years
Pregnant Patients
Laparoscopy Only
907 90.7%
Laparoscopic Appendicectomy
Open Appendicectomy
Conversion to Open
Operative details
Right Hemicolectomy
Beecher et al. World Journal of Emergency Surgery 2015, 10:6
Page 3 of 5
TTT. There was no significant difference in the outcomes for appendicectomies performed out of hours.
Table 2 Histopathology from appendicectomies
N = 907
Acute appendicitis
Organisation of emergency surgery services requires a
greater understanding of the factors influencing how we
prioritise use of limited resources within the emergency
setting. This study identifies three key factors which influence the TTT for patients with suspected appendicitis.
These patient related factors provide useful parameters
on which to prioritise patients with suspected appendicitis appropriately for emergency theatre.
Understandably, younger aged patients were identified
as having quicker access to theatre. Our emergency theatre prioritisation system ensures children <12 years of
age in need of an emergency operation are given high
priority and invariably have their intervention in a timely
manner. This is to the detriment of older patients but is
necessary in the setting of limited theatre resources.
Interestingly, a neutrophilia was found to be the only
blood parameter found to influence TTT. A neutrophilia
indicates an acute inflammatory response and would be
in keeping with an acute appendicitis and appears to
represent a good marker of the clinical severity of the
appendicitis and the timing of appendicectomy. Histological confirmation of a perforated appendix was the
final factor that influenced TTT. Although presence of a
perforation is a factor that is determined retrospectively,
these patients would have more advanced clinical signs
and signs of sepsis. This indicates that clinical exam is
indispensible in deciding who should be operated on urgently. Altogether, these patient related factors highlight
Enterobius Vermicularis
Faecolith + appendicitis
Faecolith – appendicitis
No pathology
Retrospectively, those with histopathological confirmation of a perforated appendix had also been brought to
theatre more rapidly than those without (p < 0.001). Preoperative radiology increased TTT by 52% in those patients who underwent either an ultrasound or CT scan
(p < 0.001).
On multivariate analysis, younger age, a raised neutrophil count and the presence of a perforation were found
to be independent factors influencing TTT.
Table 4 displays the impact of theatre delay in those
who had histologically confirmed appendicitis. Interestingly, there was no significant difference between any of
the outcome variables examined with or without an
8 hour delay.
Table 5 compares outcomes of those operated on during working hours and those operated on out of hours.
Time of the day did not have a significant impact on
Table 3 Factors influencing TTT
<8 Hours (447)
≥8 Hours (553)
Univariate p-value
Multivariate p-value
Radiology Pre-op (N)
Diagnostic laparoscopy
Patient age (mean)
Gender (N)
Abnormal bloods (N)
Operation type (N)
Perforation (N)
Beecher et al. World Journal of Emergency Surgery 2015, 10:6
Page 4 of 5
Table 4 Impact of theatre delays on patient outcomes for those with appendicitis
Theatre <8 hrs (N = 306)
Theatre ≥8 hrs (N = 297)
66 (21.5%)
41 (13.8%)
Conversion to open
6 (1.96%)
11 (3.7%)
LOS* (range)
3 days (1–12)
3 days (1–20)
20 (6.54%)
17 (5.72%)
13 (4.38%)
the factors that influence our decision making when
prioritising patients for an appendicectomy in the setting
of a multi-speciality emergency theatre. It is clear that
clinical prioritisation influences TTT with young age, increased neutrophils and presumably clinical signs suggesting perforation resulting in the surgeons being more
proactive in prioritising these cases. It is also clear that
while there were no clear increased complications in the
group with longer TTT it is important to realise that
this is not the same as saying all patient can wait. The
lack of increased complication rate in the delayed group
may be as a result of sicker patients being prioritised to
earlier theatre times.
This study highlights the patient related factors which
influenced TTT. It is likely there are other non-patient
related organisational factors which also have a bearing
on TTT such as staffing levels for example. However
these would difficult to measure and would vary from
institution to institution. The lack of influence of preoperative radiology on TTT was surprising. However,
the decision for theatre would not have been taken until
after the radiological investigation, thus although the
overall length of stay was delayed, the TTT by definition
was not. Interestingly the time of day does not impact
on TTT.
Delaying TTT beyond the 8 hour time frame does not
appear to affect the short-term outcome for patients
with acute appendicitis within this study. Although this
time-frame was defined by published guidelines and recent studies, we also analysed this data looking at different time-points including 8,12,16 and 24 hours [2,12].
There was no difference noted in patient short-term outcome at any of these time-points. This is consistent with
findings from a recent meta-analysis and systematic
Table 5 Subanalysis of appendicectomies performed out
of hours
Working hours
Out of hours
Time to theatre*
Length of stay*
3 days
3 days
Readmission (N)
Morbidity (N)
*Mean, hh:mm.
P value
review which demonstrated delays up to 24 hours in selected patients may be feasible as studies have shown
that a delay within this window is not associated with increased rates of complex pathology [6]. Thus there may
be scope to extend the recommended TTT within
current emergency surgery guidelines, however those
with clinical signs of perforation, neutrophillia and younger age were prioritised in this study which may suggest
the subgroups that need early surgery.
This study highlights key ‘patient related’ factors that influence TTT in patients with suspected appendicitis.
Identification of these influential factors adds greatly to
our understanding of patient prioritisation in the setting
of a dedicated emergency theatre. Finally, TTT delays
greater than 8 hour do not appear to affect short-term
patient outcomes.
Competing interests
The authors declare that they have no competing interests.
Authors’ contributions
SB collected the data & drafted the manuscript. DPO’L performed the
statistical calculations & edited the manuscript. RML edited the manuscript.
All authors read and approved the final manuscript.
Received: 11 December 2014 Accepted: 18 January 2015
Published: 29 January 2015
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Cite this article as: Beecher et al.: Hospital tests and patient related
factors influencing time-to-theatre in 1000 cases of suspected appendicitis:
a cohort study. World Journal of Emergency Surgery 2015 10:6.
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