Abstracts of FIS/HIS 2016
HIS Grants Abstracts
Evaluating the treatment of surgical site infection (SSI) in patients
undergoing surgery for spinal metastases
Ross A. Atkinson, Anna Jones, Benjamin M. Davies, Dmitri van Popta,
Karen J. Ousey, John Stephenson.
Connolly Hospital, Dublin
Surgical site infection (SSI) is a highly undesirable
complication of any surgical procedure. Spinal tumour patients, who
may have undergone chemo- and radiotherapy, are immunosuppres-
sed and nutritionally compromised, are at increased risk of SSI.
Understanding the risk to patients requiring surgery, and the costs
associated with this complication, is important for operative planning.
The aims of this project were to retrospectively audit suitability
of patients with metastatic spinal tumours for surgery based on a
recognised prognostic tool; conduct a survival analysis of patients
experiencing SSI; characterise the management plan for spinal
metastatic tumour patients experiencing SSI; and calculate the costs
associated with SSI in this patient group.
A retrospective case review study identified spinal meta-
static tumour patients both with and without SSI undergoing surgery
between January 2009 and December 2012. Eligibility for surgery
(using the Revised Tokuhashi Scoring [RTS] system) and fitness for
surgery (using the American Society of Anesthesiologists [ASA] grade)
were determined. Overall survival was assessed using the Kaplan-
Meier method. A semi-parametric Cox proportional hazards survival
(time-to-event) analysis was undertaken to assess the relationships
between covariates and survival. The management of those with SSI
was reviewed from existing clinical documentation, and the costs to
the service associated with SSI were calculated.
A total of 176 surgical procedures for metastatic spinal
tumours were undertaken in 152 patients (77 females and 75 males,
mean age 60.5 ± 12.9 years) over the four year study period. SSI
occurred following 17 procedures in 17 patients (SSI rate 11.2 per 100
patients; 9.7 per 100 procedures). As expected, better survival was
observed in patients with higher RTS scores and lower ASA grades.
Survival was substantively better in patients without SSI (median
276 days [95% CI 183
369 days]) when compared with those with SSI
(median 135 days [95% CI 62
208 days]) (P = 0.075). Costs were
significantly higher in patients with SSI when compared with a
random sample of patients without SSI (p = 0.019). In-patient hos-
pital stay and return to theatre were the main costs associated with
SSI. Return to theatre was the most expensive single intervention
employed to treat SSI.
Both RTS and ASA can be used as indicators of patient
survival in those undergoing surgery for spinal metastases. SSI has a
negative impact on survival, but a larger study sample would be
needed to confirm this. SSI in this patient group significantly increases
healthcare costs, mainly due to prolonged hospitalisation and return
to theatre for wound management.
Do biocides increase antibiotic resistance in
, K. Hopkins
, M. Sutton
, N. Woodford
, J.-Y. Maillard
School of Pharmacy and Pharmaceutical Sciences, Cardiff University,
PHE Colindale, London,
PHE Porton Down, UK
Since the discovery of penicillin in 1929, antibiotics have been heavily
used and misused to treat bacterial infections. This resulted in an
increased number of multidrug resistant bacteria. Bacteria are
adapting faster to antibiotics than pharmaceutical companies are
able to introduce new ones on the market. Therefore, multi-drug
resistant organisms are becoming one of the most important concerns
worldwide. Without any new family of antibiotics developed within
the last decade, infection prevention and control measures are
predominant, relying on the efficiency of biocides to contain the
. Biocides are now extensively used, questioning
their impact on the development and transfer of resistance mechan-
isms within bacteria. The selective pressure exerted by biocides could
lead to co-selection and cross-resistance mechanisms, enhancing the
maintenance and transfer of resistance genes.
As little is still known about the impact of biocides on antibiotic
resistance, this study aims to investigate four commonly used biocides,
including a quaternary ammonium compound (benzalkonium chlor-
ide), a biguanide (chlorhexidine digluconate) and two heavy metals
(copper sulfate and silver nitrate), on the maintenance and transfer
of carbapenem-resistance genes among
clinical isolates. Using microdilution broth method, minimum inhibi-
tory and bactericidal concentrations (MICs and MBCs) were deter-
mined for 210 clinical isolates. For each biocide, the distribution
presented a single modal value, except for copper where a bi-modal
distribution with two peaks was observed. Correlations studies were
performed using Spearman
s nonparametric test to detect potential
links between the susceptibility profiles to biocides and antibiotics.
Regardless of the bacterial species, weak to moderate but significant
correlations (p < 0.05 to p < 0.001) were found between the MICs of
benzalkonium chloride and chlorhexidine. For
correlations between elevated MICs and MBCs of benzalkonium
chloride or silver nitrate and elevated MICs of ertapenem were
observed. Furthermore high MICs/MBCs of chlorhexidine and clinical
resistance to imipenem, meropenem and ertapenem were identified.
Further studies are needed to investigate the reasons behind these
: contamination of tap outlet fittings
and consequential contamination of tap water
University of Southampton and Public Health
Recent neonatal deaths were linked to
the contamination of hospital tap water. Investigations demonstrated
that the tap outlet fittings (OFs) were heavily colonised by
. Cross-contamination during cleaning has been implicated
in OF contamination.
To investigate the contamination of OFs via contaminated cleaning
cloths and the consequential contamination of water delivered from
both frequently and infrequently used taps.
Microfibre cloths contaminated with
used towipe three different types of OF (A, B and C). OFs were inserted
into an experimental tap rig for up to 24-hours. Survival over time was
assessed by culture. Taps were used at high-and low-frequencies by
subjecting taps to single, and multiple flushes. Water was sampled via
The median number of
transferred from cloths to OFs was
1.4 × 10
persisted on all OFs for 24-hours. However,
in comparison to OFA, significantly fewer organisms were recovered
from OFB and C after 8- and 12 h respectively.
At all time points and despite tap usage,
from water delivered from OFA at levels above the augmented care
alert level (i.e.
10 CFU/100 mL). Water delivered from OFB did not
beyond the first flush.
Contamination of OFs via cleaning cloths is possible and can lead
to contaminated water being eluted from frequently- and infre-
quently-used taps. OF design, whilst not removing the potential
for retrograde contamination, may, in combination with a flushing
regimen, reduce the risk of persistent contaminant presence in the
0195-6701/© 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.