An Observational Study on Validity of DULK Score as a Tool for Early Diagnosis of Anastomotic Leakage in the Immediate Post-Operative Period After Elective Primary Intestinal Anastomosis
Conditions: Anastomosis, Leaking
Sponsor: Sawai Mansingh Medical College

10-10-2024
“An observational study on validity of DULK score as a tool for early diagnosis of
anastomotic leakage in immediate post-operative period after elective primary intestinal
anastomosis.”
ABSTRACT
Background: Anastomotic leakage (AL) is a significant complication of intestinal
anastomoses, that contributes to increased morbidity, mortality, and prolonged hospital stay.
This study evaluated the effectiveness and accuracy of the Dutch Leakage Score (DULK), a
postoperative scoring system, for the early detection of AL following elective open intestinal
anastomosis.
Methods: A total of 86 cases meeting the inclusion and exclusion criteria were included in
this observational study from SMS Medical College, Jaipur, over a duration of 14 months,
from March 2023 to May 2024. Postoperative assessments were conducted using the DULK
score on days 1, 3, 5, 7, and 12 to evaluate its validity as an early diagnostic tool for
anastomotic leakage and to identify associated risk factors.
Results: The study confirmed that the DULK score is a reliable tool for detecting
anastomotic leaks, with a sensitivity of 84.37% and specificity of 79.62%. Key risk factors
included anemia (58.3% leak rate), hypoalbuminemia (75% leak rate), and leukocytosis
(66.6% leak rate), emphasizing their significance in predicting leak.
Conclusion: DULK score with a cut-off value of 8 is an effective diagnostic tool for
anastomotic leaks, demonstrating its significance in early detection and the management of
anastomotic leak.
Key words: Anastomotic leakage, DULK score, Early diagnosis, Risk factors, Predictive tool,
Surgical outcomes.
INTRODUCTION
Anastomotic leakage (AL) is a serious complication following intestinal surgery, despite
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advancements in surgical techniques. Defined as a defect in the intestinal wall at the anastomotic site,
AL leads to communication between intra- and extraluminal compartments.(1) The variability in
definitions and diagnostic criteria across studies complicates the assessment of AL incidence, with up
to 24% reported in distal rectal surgeries, whereas the overall rates for intestinal surgeries range from
6%-7%. (2) Anastomotic leaks results in increased morbidity, mortality, and prolonged hospital stays.
In colorectal cancer patients, AL has been linked to decreased long-term survival and higher local
recurrence rates.(3)
The clinical presentation of AL can vary widely, from subtle signs, such as low-grade fever and
abdominal pain to severe conditions, such as sepsis and peritonitis. Early diagnosis is critical because
delayed detection can lead to severe complications, including the need for reoperation and intensive
care. Traditional diagnostic methods often fall short, necessitating imaging studies such as CT scans,
which are more effective than contrast enemas in identifying leaks. Multiple risk factors contribute to
the occurrence of AL, including surgical technique, local sepsis, ischemia at the anastomosis site, and
patient-related factors such as age, obesity, and pre-existing health conditions.(4)
Studies have shown that timely intervention can significantly reduce the mortality rates associated
with AL, emphasizing the need for effective diagnostic tools. (5) The DULK Score a postoperative
scoring system developed for the early detection of AL, has shown promise in previous studies,
demonstrating early diagnosis and lower postoperative mortality. This study aimed to evaluate the
effectiveness and accuracy of the DULK Score in detecting AL following elective open intestinal
anastomosis. Specifically, it will assess the score's sensitivity and specificity, investigate its
correlation with AL occurrence, and analyse individual risk factors contributing to anastomotic leak.
Table 1: Various clinical parameters used to assess DULK score (4)
Variables
Fever
Respiratory rate
Heart rate
Oliguria
Mental Status
Clinical condition
Ileus/Bowel obstruction
Gastric retention
Surgical wound
dehiscence
Abdominal pain other
than wound pain
Signs of infection
Threshold
Scores
> 38o C
1
> 30/min
1
> 100/min
1
<30 ml/h or 700 ml/d
1
Agitation or lethargic
2
Deterioration
2
Present
2
Present
2
Present
2
Present
2
Leucocytosis or
1
2

Renal function
Nutrition
CRP- C-Reactive Protein
elevated CRP
Creatinine elevation or
1
urea by 5%
Parenteral nutrition
2
AIM & OBJECTIVES:
Our aim was to assess the validity of the DULK Score as a tool for the early diagnosis of
anastomotic leakage in the immediate post-operative period following elective primary
intestinal anastomosis through an observational study.
The objectives were:
1. To evaluate the accuracy and reliability of the DULK Score in detecting anastomotic
leakage in patients undergoing elective primary intestinal anastomosis.
2. To analyze the association between DULK Score results and the occurrence of
anastomotic leakage in the immediate post-operative period.
3. To assess the practicality and feasibility of implementing the DULK Score as a routine
diagnostic tool for anastomotic leakage in clinical practice.
MATERIALS AND METHODS
The study involved patients undergoing elective intestinal anastomosis at SMS Medical
College, Jaipur, with informed consent obtained prior to participation. A sample size of 86
was chosen, considering a 15% attrition rate. Inclusion criteria included adults over 18, while
emergency surgeries and certain patient conditions were excluded. The methodology
involved collecting detailed medical histories, conducting comprehensive investigations
(blood tests and imaging), and performing elective surgeries. Postoperatively, patients were
assessed using the DULK Score to monitor anastomotic leakage risk. Post op monitoring of
clinical parameters and investigations was done to calculate DULK score on days 1, 3, 5,7
and 12.
OBSERVATIONS
Incidence and Demographic variables
A total of 86 patients were included in the study, comprising 48 (59%) male and 38 (41%)
female patients. Anastomotic leaks occurred in 32 patients (37.2% of the population) with 19
males and 13 females. Males had a 59.3% leak rate at p value of 0.6087, indicating non-
significance as a risk factor. The highest incidence was in the 50-60 age group (28%), with
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75% of those over 60 experiencing leaks. Over 50% of patients above 40 years developed
leaks, while the rate was 20% or less in those under 40.
Association of various Risk Factors with anastomotic leak
In our study, 12 patients (13.9%) were anemic, with 58.3% developing leaks, indicating
anemia increases leak risk by 2.7 times (p = 0.10). Hypoalbuminemia was present in 27.9%
of cases, with a significant 75% leak rate (p < 0.00001), making patients 10.2 times more
susceptible. Leukocytosis was observed in 34.8%, with 66.6% developing leaks (p =
0.00003), raising risk by 7.3 times. Among leak patients, 21.8% had anemia, 62.5% had
leukocytosis, and 56.2% had hypoalbuminemia.
Table 2: Association of various risk factors with percentage anastomotic leak
No of patients in No. of patients Percentage
Risk factor
study group with with risk factor
risk factor
Hypoalbuminemia
24
who
develop
leak
18
75 %
ASA
status
(2
or 39
29
74.3 %
above)
Raised WBC count
30
20
66.6 %
Anemia
12
7
58.3 %
Immunocompromised 11
6
54.5 %
Chronic disease
44
23
52.2 %
Chronic steroid use
14
7
50 %
Gender (Male)
48
19
39.5 %
ASA- American society of anesthesiologists; WBC- white blood cells;
Timing of leak and DULK Score cut off value
The majority of leaks were identified on postoperative day 5 (56.2%), with only 2 leaks
occurring beyond postoperative day 7. Out of 32 patients who had leak 27 patients had
DULK score of 8 while only 5 patients had score of less than 8. At cut-off score of 8, the
DULK Score exhibited a sensitivity of 84.37%, specificity of 79.62%, positive predictive
value (PPV) of 71.05%, and negative predictive value (NPV) of 89.58%.
Table 3: Post op Day when leak is identified
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Post Op Day
(POD)
POD-3
POD-5
POD-7
POD-12
Total
No of
Percen
patients
tage
4
12.5 %
18
56.25
%
8
25 %
2
6.25 %
32
Table 4: DULK Score cut-off and Anastomotic leak
DULK
Score
8 or more
<8
Total
Leak No leak
27
11
5
43
32
54
Surgical Techniques, site of anastomosis and duration
Analysis of surgical techniques revealed no significant difference between hand-sewn and
stapled anastomoses (p-value: 0.475). Of the 68 patients who underwent hand-sewn
anastomosis, 24 (35.2%) experienced leaks, while 8 of 18 patients (44.4%) with stapled
anastomosis developed leaks. Colo-colic anastomoses had the highest leak rate (40.7%),
followed by ileo-colic (35.2%) and ileo-ileal (34.2%).
Furthermore, prolonged surgery duration (>4 hours) was associated with a higher risk of AL,
with 54.5% of patients experiencing leaks
compared to 34.6% for surgeries lasting less than 4 hours. Cases performed by residents
under the guidance of consultant showed a higher incidence of leaks (42.5%) compared to
those performed by consultants (32.6%), although this difference was not statistically
significant (p-value: 0.343).
Table 5: Correlation of anastomotic technique with leak
5

Technique
Hand sewn
Stapled
Total
Leak No leak
24
44
8
10
32
54
Table 6: Correlation of site of anastomosis with site of leak
Site
Ileo-ileal
Colo-colic
Ileo-colic
Jejuno-
jejunal
Total
Leak No Leak
13
25
11
16
6
11
2
2
32
54
Percentage leak
34.2
40.7
35.2
50
DISCUSSION
Our study reinforces the findings of previous research regarding the DULK Score as a
significant predictive tool for anastomotic leakage (AL). The DULK score, established to
reduce diagnostic delays and associated mortality rates, demonstrated good performance in
our cohort, with a cut-off score of 8 yielding a sensitivity of 84.37% and specificity of
79.62%. These metrics highlight the score's utility in early detection, allowing for timely
interventions that can significantly alter patient outcomes.
In our analysis of 86 patients, 37.2% developed AL, with the majority of leaks occurring on
postoperative day 5 (56.2% of leaks), mirroring previous study done by Das et al (2013) that
report a peak detection window between postoperative days 5 and 8.(6) In previous studies it
was established that leak rates are high for very proximal (oesophageal) and very distal (low
rectal) anastomoses. (7) In our study 40.7% of colo-colic anastomosis and 35.2% of ileo- colic
anastomosis developed leak. Leak percentage was lowest in ileo ileal 34.2% concluding leak
rates are high for distal anastomoses compared to proximal anastomoses.
Additionally, we identified critical risk factors contributing to AL, including
hypoalbuminemia, which was present in 27.9% of cases with a staggering 75% leak rate
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among those affected in consistent with study done by Anandan PK et al.(8) Similarly,
leukocytosis was found in 34.8% of patients, with 66.6% of these individuals experiencing
AL, indicating a 7.3 times higher risk compared to those with normal white blood cell counts
comparable to results from study done by Zarnescu et al (2021). (9) Chronic disease status
emerged as a significant predictor, with a p-value of 0.0031, affirming its association with
increased leakage risk.
These findings emphasize the need for vigilance in monitoring patients with identified risk
factors, particularly hypoalbuminemia and leukocytosis. Incorporating the DULK score or
modified DULK score (10), which is based on fewer parameters like abdominal pain,
tachypnoea, rise in CRP and clinical deterioration into clinical practice or may enable
healthcare providers to stratify risk more effectively and implement proactive management
strategies, ultimately improving postoperative outcomes for patients undergoing
anastomosis.
The study's limitations include a small sample size, single-centre design, potential
subjectivity in DULK Score assessments, exclusion of certain patient groups (emergency
surgeries), limited follow-up duration, unaccounted confounding variables, and variability in
surgical techniques, affecting the generalizability of results.
CONCLUSION
The study explored factors influencing anastomotic leaks following elective intestinal
anastomosis, emphasizing the significance of various patient demographics and clinical
conditions in predicting leak risk. This study confirms the DULK as a reliable early
diagnostic tool for anastomotic leaks, achieving a sensitivity of 84.37% and specificity of
79.62%. Its effectiveness in identifying leaks by postoperative day 5 highlights its potential to
enhance clinical decision-making and improve patient management.
Funding: No funding sources
Conflict of interest: None
Ethical approval: The study was approved by the institutional ethics committee
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