Emergency Surgery for Colon Diseases in Elderly Patients. Analysis of Complications, and Postoperative Course
Conditions: Emergency Colorectal Surgery in Ultra 80 Patients
Sponsor: University of Foggia

Emergency surgery for colon diseases in elderly patients. 
1 
Analysis of complications, and postoperative course. 
2 
Keywords: Emergency surgery, colon diseases, elderly patients, 
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CR-POSSUM score 
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Short title: Colorectal emergencies  in elderly patients. 
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Date 25/06/2022 
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9 
Abstract  
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Background Colon diseases can turn in a clinical emergency with the onset of some 
11 
important complications. Some critical conditions are more common in aged patients 
12 
because they are more frails. The aim of this study is to examine ultra 80 patients, 
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undergoing emergency colorectal surgery, evaluating the aspects associated with post-
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operative complications and other problems in the short term. 
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Methods From November 2020 to February 2022 we have included 32 consecutive 
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patients older than 80 undergoing emergency surgery due to colon diseases. We have 
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collected and analysed all demographic, and operative data and then applied CR-
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POSSUM score and correlated with postoperative hospital stay and the onset of 
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postoperative complications according to Clavien Dindo classification. 
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Results Postoperative factors were selectively evaluated based on the clinical scenario 
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and different colic pathologies. There was no statistically significant differences, in terms of 
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postoperative hospital stay, postoperative complications, reoperation rate and 30-day 
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mortality. The number of cases of blood transfusions was significant, more numerous in 
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case of intestinal perforation and bleeding cases. The value of Operative Severity Score in 
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the Bowel Perforations, was significantly higher.  
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Conclusions The use of a score to stratify the risk is a useful tool especially in elderly 
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patients to undergo emergency surgery. The CR-POSSUM score was important for 
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predicting morbidity in our study. Emergency manifestations of colon diseases in the 
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elderly show higher morbidity and mortality rates. The effect of age on outcome is a 
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concept that needs to be emphasized, so further investigation is needed. 
 
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Introduction 
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Colorectal emergencies are among the most frequent in the field of abdominal surgery 1. 
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Colon perforation can cause severe sepsis, with subsequent multiple organs dysfunction, 
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but colonic intestinal occlusions or haemorrhages are also clinical scenarios that should 
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not be underestimated, as they might lead to life-threatening conditions for the patient 2. 
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Frequently emergency surgery affects elderly patients, in fact several critical conditions are 
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more common in geriatric patients because they are frailer and might suffer a delay in 
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diagnosis 3 4. 
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Surgical choices are mutable and may include treatments with radical or palliative intent, 
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based on the severity of the disease and with the sole intent of saving the patient's life. 
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The onset of complications like occlusion, bleeding and perforation worsen morbidity and 
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postoperative mortality 5 6. 
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Emergency surgery, in general, is featured by a higher morbidity and mortality rate in 
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comparison with elective surgery, (it can reach rates 33.6-64% and 20-34%, respectively7). 
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Moreover, old age is considered a risk factor for emergency surgery in patients with 
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colorectal diseases, and this assumption often influences the idea that surgery is 
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associated with postoperative risks overwhelming the benefits8. These considerations 
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make emergencies associated to colorectal pathologies a real challenge for surgeons. 
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The aims of this study are to analyse the profile of ultra 80 patients, undergoing 
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emergency colorectal surgery, evaluating the possible correlation between the factors 
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associated with post-operative complications and other problems in the short term. 
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Methods 
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From November 2020 to February 2022 we have performed 253 procedure of colonic 
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surgery. The average age of the total number of patients treated was 69.4 years, with a 
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percentage of patients over eighty of 26.8%. 61% of the operations were performed as 
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elective surgery while 39% as an emergency, of which 78 in the first 24 hours. All cases of 
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trauma were excluded. 32 consecutive patients older than 80 undergoing emergency 
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surgery (within 24 hours) due to colon diseases were included in this retrospective study. 
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All the demographic data have been collected (Table 1), and in order to better evaluate the 
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factors and the aspects influencing the postoperative course, we separately considered 
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the clinical picture of the emergency and the nature of the disease, collecting data on 
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postoperative hospitalization, onset of postoperative complications (according to the 
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Clavien Dindo classification 9), blood transfusions, reoperation rate and 30-day mortality, 
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analyzed with the Significance Tests, ANOVA test. We then applied the modified 
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POSSUM score (Physiological and Operative Severity Score for the enUmeration of 
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Mortality and morbidity) for colorectal surgery (CR-POSSUM score 10) and correlated with 
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postoperative hospital stay and the onset of postoperative complications according to 
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Clavien Dindo classification, using Pearson Correlation Coefficient (ρ). All patients 
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underwent short-term follow-up for up to 30 days after discharge. 
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Table 1 Demographic data. Patients treated in emergency surgery for colon diseases. Data are expressed 
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as mean, or percentage values 
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Results 
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Postoperative factors were selectively evaluated based on the clinical scenario 
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determining the surgical emergency (Table 2). 
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There was no statistically significant difference between the three groups (Bowel 
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Ostruction, Bowel perforation and Bleeding), in terms of postoperative hospital stay, 
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postoperative complications, reoperation rate and 30-day mortality. On the other hand, the 
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number of cases of blood transfusions was significant, more numerous in case of intestinal 
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perforation and bleeding (Table 2). 
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Table 2 Post surgical data, in different clinical pictures. Significance Tests used are ANOVA and Chi-Square. 
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No significant differences were found in the three groups of colic pathologies considered 
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(Malignancy, Diverticulitis, Ischemic bowel disease). The Ischemic bowel disease group 
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had an average postoperative hospital stay, longer as well as the cases of blood 
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transfusions compared to the other two groups, albeit not significant (Table 3).  
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Table 3 Post surgical data, in different colon diseases. Significance Tests used are ANOVA and Chi-Square. 
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All patients in the study underwent the CR-POSSUM score. We selectively analyzed the 
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three parameters of the CR-POSSUM (Physiology Score, Operative Severity Score, 
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Mortality), for each clinical scenario and colon disease. In our cohort, the highest value of 
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Operative Severity Score in the Bowel Perforations group was statistically significant 
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(Table 4 and Table 5). 
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Table 4 CR-POSSUM in different clinical pictures. Significance Test used is ANOVA test. 
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Table 5 CR-POSSUM. in different colon diseases. Significance Test used is ANOVA test. 
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Finally we analyzed the results obtained, with Pearson's Tests of Correlation. A significant 
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correlation was observed between Physiology Score, Mortality rate and postoperative 
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complications according to Clavien Dindo classification (ρ= 0.479 p value=0.05; ρ= 0.399 p 
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value= 0.023). In the analysis of the postoperative hospital stay, there was always a 
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positive correlation (ρ> 0) but not statistically significant (Graph 1 and Graph 2). 
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Graph 1 Pearson Correlation Coefficient to predict Postoperative Hospital Stay.. A. Physiology Score and 
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Postoperative Hospital Stay (ρ= 0.193 p value= 0.289). B Operative Severity Score and Postoperative 
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Hospital Stay (ρ= 0.07 p value= 0.703). C Mortality Rate and Postoperative Hospital Stay (ρ= 0.269 p value= 
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0.136). 
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Graph 2 Pearson Correlation Coefficient to predict postoperative complications according to Clavien Dindo 
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Classification  . A. Physiology Score and Clavien Dindo Classification  (ρ= 0.479 p value=0.05). B Operative 
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Severity Score and Clavien Dindo Classification (ρ= -0.174 p value= 0.340). C Mortality Rate and and 
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Clavien Dindo Classification (ρ= 0.399 p value= 0.023). 
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Discussion 
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Acute abdomen in aged patients represents a real challenge to all surgeons. The atypical 
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presentation of the disease occurs very frequently in this group of patients and the 
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diagnosis is often only possible employing instrumental tests. The diagnosis might 
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consequently come late also because these patients eventually live in alienation, do not 
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adhere to screening programs, and these aspects are furtherly accentuated in the 
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pandemic SaRS COV 2 era11 12. If the presence of a surgical condition is confirmed, then 
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surgical treatment is mandatory and the decision making in such cases might be very 
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challenging. 
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The results of our study show that elderly patients undergoing emergency surgery for 
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colonic disease suffer from a 30-day mortality rate of 15.6% and a malignant disease rate 
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of 25%. 
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In our study the complications recorded they were easily manageable, with only four cases 
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(12.5%) of reoperations (Clavien Dindo IIIa). Many data obtained between the 
127 
comparisons of the three groups are not statistically significant, although we recorded a 
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unfavourable postoperative course for intestinal perforations, among the different clinical 
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scenarios, and for intestinal ischemia when comparing colon diseases. In the evaluation of 
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the CR-POSSUM score, the difference in the Operative Severity Score compared between 
131 
the different clinical scenarios was significant. 
132 
The principal emergencies related to colorectal diseases are intestinal obstruction, 
133 
haemorrhage and perforation. Intestinal obstruction is the most frequent in literature 13 14 
134 
and represents 46.8% of the cases in ours study. The cases of malignancy are often 
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characterized by advanced stage disease and / or metastatic disease, for which surgery is 
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often not performed with radical intents but with the aim of saving the patient's life. This 
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circumstance occurs more frequently in elderly patients 15 16. 
138 

 
139 
Age cannot represent a prognostic factor by itself when dealing with survival rates in 
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colonic surgery 17, but there is no doubt that the presence of comorbidities in elderly 
141 
patients is higher and influence the clinical course 18.  
142 
The high mortality and morbidity rates described in emergency interventions emphasise 
143 
the need for vigilant preoperative assessments to correct comorbidities, as colon diseases 
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also lead to special deficit states such as anaemia, malnutrition and sepsis in the worse 
145 
scenarios 19 20. 
146 
From these premises arise the need to categorize these patients according to a reliable 
147 
scoring system, which might allow to objectively stratify the perioperative risk and better 
148 
communicate with the patients' relatives. CR-POSSUM come from the POSSUM and P-
149 
POSSUM models for surgical mortality and morbidity risk estimate. This adjustment of the 
150 
POSSUM model is indicated for patients undergoing colorectal surgery 21. It can be 
151 
employed for both emergency and elective surgery, but there is not a specific value 
152 
indicating emergency treatment, and this is, in our opinion, a limitation of this score. On the 
153 
other hand, a worse score will be assigned considering the patient's age, advanced cancer 
154 
stage or in case of peritoneal contamination. 
155 
 In our study we therefore thought that CR-POSSUM, originally developed to predict 
156 
mortality, might also be utilized to foresee morbidity. To demonstrate this, we performed 
157 
an analysis using the Pearson Correlation Coefficient between the values obtained in the 
158 
CR-POSSUM, and the postoperative hospital stay and staged complications according to 
159 
the Clavien Dindo classification. We intend the postoperative hospital stay value as a 
160 
parameter that could correlate with the recovery of the elderly and frail patient, as well as 
161 
being a parameter related to general costs 22. We consider the obtained results interesting 
162 
because in all cases a positive relationship with a ρ > 0, (except for Operative Severity 
163 

Score and Clavien Dindo Classification), was recorded and the acquired data were 
164 
statistically significant when compared with Physiology Score and Clavien Dindo 
165 
Classification (ρ = 0.479 p value = 0.05) and Mortality Rate and Clavien Dindo 
166 
Classification (ρ= 0.399 p value= 0.023).We could infer that the values obtained from the 
167 
CR-POSSUM score are reliable to analyse them separately and that this approach can 
168 
help surgeons in predicting the clinical trends of the patient operated in emergency regime. 
169 
 
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171 

Conclusion  
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Dealing with stratification of the operative risk, we believe in the usefulness of a score that 
173 
provides objective information and allows the assessment of mortality and morbidity risk 
174 
values. This might also be considered as a useful tool in communicating with the patients, 
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who might only rely on surgery as a therapeutic choice. The CR-POSSUM score is a 
176 
consistent scoring system that expressed a significant value in predicting morbidity, 
177 
although no indicator assigning a higher score to emergency interventions is available. 
178 
Emergency manifestations of colon diseases in the elderly are frequent and show higher 
179 
morbidity and mortality rates in comparison with elective admissions. The impact of old 
180 
age on outcomes is a concept that must be underlined and emphasized, because it is 
181 
associated with poor surgical results of this population. 
182 
In critical situations, the patient's survival must be the only goal to pursue, despite a 
183 
possible complicated postoperative course. Further investigation with adjunctive 
184 
prospective studies, will improve our knowledge on these situations. 
185 
 
 
186 

Table 6 Demographic data. Patients treated in emergency surgery for colon diseases. Data are expressed as mean, or 
187 
percentage values 
188 
 
N= 32 
Age (years) 
86 (80-95) 
Male sex  
16 (50%) 
BMI 
24.5 
Previous surgery 
38% 
Malignancy Rate 
25% 
Death at 30 days 
15.6% 
 
189 
 
190 
Table 7 Post surgical data, in different clinical pictures. Significance Tests used are ANOVA and Chi-Square. 
191 
 
Bowel Obstruction 
(n=15) 
Bowel Perforation 
(n=11) 
Bleeding  
(n=6) 
 
Postoperative Hospital 
Stay 
 
8.3 (7-15) 
 
11.1 (2-26) 
 
9 (5-15) 
 
p= 0,434 
Clavien Dindo 
Grade 0 
Grade I 
Grade II 
Grade IIIa 
 
2/15 (13.3%) 
7/15 (46.7%) 
5/15 (33.3%) 
1/15 (6.7%) 
 
3/11 (27.3%) 
2/11 (18.2%) 
4/11 (36.4%) 
2/11 (18.2%) 
 
1/6 (16.7%) 
2/6 (33.3%) 
2/6 (33.3%) 
1/6 (16.7%) 
 
 
 
 
p=0.812 
Blood Transfusion 
2/15 (13.3%) 
4/11 (36.4%) 
4/6 (66.7%) 
p=0.05 
Reoperation 
1/15 (6.7%) 
2/11 (18.2%) 
1/6 (16.7%) 
p=0.641 
30 days Mortality 
3/15 (20%) 
2/11 (18.2%) 
0 
p=0.907 
 
192 
 
193 
Table 8 Post surgical data, in different colon diseases. Significance Tests used are ANOVA and Chi-Square. 
194 
 
Malignancy  
(n=12) 
Diverticulitis 
(n=15) 
Ischemic bowel 
disease (n=5) 
 
Postoperative Hospital 
Stay 
 
9.5 (7-15) 
 
8.6 (2-24) 
 
11.6 (7-26) 
 
p= 0.567 
Clavien Dindo 
Grade 0 
Grade I 
Grade II 
Grade IIIa 
 
1/12 (8.3%) 
5/12 (41.7%) 
4/12 (33.3%) 
2/12 (16.7%) 
 
4/15 (26.7%) 
5/15 (33.3%) 
5/15 (33.3%) 
1/15 (6.7%) 
 
1/5 (20%) 
1/5 (20%) 
2/5 (40%) 
1/5 (20%)  
 
 
 
 
p=0.863 
Blood Transfusion 
4/12 (33.3%) 
3/15 (20%)  
3/5 (60%)  
p=0.242 
Reoperation 
2/12 (16.7%) 
1/15 (6.7%)  
1/5 (20%) 
p=0.633 
30 days Mortality 
3/12 (25.0%) 
1/15 (6.7%) 
1/5 (20%) 
p=0.409 
 
195 
 
 
196 

 
197 
Table 9 CR-POSSUM in different clinical pictures. Significance Test used is ANOVA test. 
198 
 
Bowel Obstruction 
(n=15) 
Bowel Perforation 
(n=11) 
Bleeding  
(n=6) 
P value 
CR-POSSUM 
  
  
 
 
Physiology Score 
17.866 
17.091 
17.5 
0.283 
Operative Severity 
Score 
8.533 
9.818 
8.5 
<0.001 
Mortality (%) 
37.9% 
42.1% 
35% 
0.191 
 
 
 
 
 
 
199 
Table 10 CR-POSSUM. in different colon diseases. Significance Test used is ANOVA test. 
200 
 
Malignancy  
(n=12) 
Diverticulitis 
(n=15) 
Ischemic bowel 
disease (n=5) 
P value 
CR-POSSUM 
  
  
 
 
Physiology Score 
17.416 
17.467 
18 
0.655 
Operative Severity 
Score 
8.833 
9.133 
8.8 
0.635 
Mortality (%) 
36.6% 
39.8% 
41.1% 
0.488 
 
 
 
 
 
 
201 
 
202 
 
 
203 

Graph 3 Pearson Correlation Coefficient to predict Postoperative Hospital Stay.. A. Physiology Score and Postoperative Hospital Stay (ρ= 0.193 
p value= 0.289). B Operative Severity Score and Postoperative Hospital Stay (ρ= 0.07 p value= 0.703). C Mortality Rate and Postoperative 
Hospital Stay (ρ= 0.269 p value= 0.136). 
 
204 
 
205 
A 
206 
B 
 
207 
 
208 
C 
 
209 
 
 
210 

Graph 4 Pearson Correlation Coefficient to predict postoperative complications according to Clavien Dindo Classification  . A. 
211 
Physiology Score and Clavien Dindo Classification  (ρ= 0.479 p value=0.05). B Operative Severity Score and Clavien Dindo 
212 
Classification (ρ= -0.174 p value= 0.340). C Mortality Rate and and Clavien Dindo Classification (ρ= 0.399 p value= 0.023). 
213 
 
214 
A 
 
215 
 
216 
B 
 
217 
 
218 
C 
 
219 
 
220 

 
 
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