Ullah W, Rashid MU, Mehmood A, Zafar Y, Hussain I, Sarvepalli D, Hasan MK. Splenic injuries secondary to colonoscopy: Rare but serious complication. World J Gastrointest Surg 2020; 12(2): 55-67 [PMID: PMC7044106 DOI: 10.4240/wjgs.v12.i2.55]
Corresponding Author of This Article
Mamoon Ur Rashid, MBBS, MD, Doctor, Medical Resident, Department of Internal Medicine, Advent Health Hospital, 2501 North Orange Avenue, Orlando, FL 32804, United States. mamoon.rashid.md@adventhealth.com
Research Domain of This Article
Gastroenterology & Hepatology
Article-Type of This Article
Systematic Reviews
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Author contributions: All authors equally contributed to this paper with conception and design of the study, literature review and analysis, drafting and critical revision and editing, and final approval of the final version.
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PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Mamoon Ur Rashid, MBBS, MD, Doctor, Medical Resident, Department of Internal Medicine, Advent Health Hospital, 2501 North Orange Avenue, Orlando, FL 32804, United States. mamoon.rashid.md@adventhealth.com
Received: September 6, 2019 Peer-review started: September 6, 2019 First decision: September 28, 2019 Revised: November 23, 2019 Accepted: December 14, 2019 Article in press: December 14, 2019 Published online: February 27, 2020 Processing time: 132 Days and 9.1 Hours
Abstract
BACKGROUND
Colonoscopy is a safe and routine diagnostic and therapeutic procedure for evaluation of large bowel diseases. Most common procedure related complications include bleeding and perforation but rarely a splenic Injury.
AIM
To investigate the reason for colonoscopy, presentation of patient with spleen injury, types of injury, diagnosis, management and outcomes of patients
METHODS
A structured search on four databases was done and 45 articles with 68 patients were selected. The reason for colonoscopy, presentation of patient with spleen injury, types of injury, diagnosis, management and outcomes of patients were identified and analyzed using SPSS.
RESULTS
The mean age of the patients was 62.7 years with 64% females. Twenty two percent had a complete splenic rupture with colonoscopy while 63% had subcapsular hematoma, spleen laceration and spleen avulsion. The most common reason for colonoscopy was screening (46%) followed by diagnostic colonoscopy (28%). Eighty seven percent of patients presented with abdominal pain. Patients with spleen rupture mostly required splenectomy (47%), while minor spleen hematomas and lacerations were managed conservatively (38%). Six percent of the patients were managed with proximal splenic artery splenic embolization and 4% were managed with laparoscopic repair. The overall mortality was 10% while 77% had complete recovery. The reason of colonoscopy against presentation specifically, abdominal pain showed no statistical significance P = 0.69. The indication of colonoscopy had no significant impact on incidence of splenic injury (P = 0.89). Majority of the patients (47%) were managed with splenectomy while the rest were managed conservatively (P = 0.04). This association was moderately strong at a cramer’s V test (0.34). The Fisher exact test showed a higher mortality with spleen rupture (P = 0.028).
CONCLUSION
Spleen rupture due to colonoscopy is a significant concern and is associated with high mortality. The management of the patients can be individualized based on clinical presentation.
Core tip: Colonoscopy is a safe diagnostic and therapeutic procedure for evaluation of large bowel diseases. Rarely, a splenic Injury can occur. We perform a structured search on four databases and selected 45 articles with 68 patients. The reason for colonoscopy, presentation of patient with spleen injury, types of injury, diagnosis, management and outcomes of patients were identified and analyzed. The most common reason for colonoscopy was screening (46%) followed by diagnostic colonoscopy (28%). Eighty seven percent of patients presented with abdominal pain. Patients with spleen rupture mostly required splenectomy (47%), while minor spleen hematomas and lacerations were managed conservatively (38%). Six percent of the patients were managed with proximal splenic artery splenic embolization and 4% were managed with laparoscopic repair. The overall mortality was 10% while 77% had complete recovery. Spleen rupture due to colonoscopy is a significant concern and is associated with high mortality. The management of the patients can be individualized based on clinical presentation.
Citation: Ullah W, Rashid MU, Mehmood A, Zafar Y, Hussain I, Sarvepalli D, Hasan MK. Splenic injuries secondary to colonoscopy: Rare but serious complication. World J Gastrointest Surg 2020; 12(2): 55-67
Colonoscopy is a safe and routine procedure performed for evaluation of large bowel diseases. The most common post procedure complications include bleeding and perforation. Splenic Injury, a rare complication after colonoscopy was first reported by Wherry and Zehner[1] in 1974. Since then, the reported incidence is on the rise and is estimated to be 1 in 100000 procedures. Possible reasons include increased utilization of colonoscopy for management of gastrointestinal disorders including polypectomy and increased rate of screening colonoscopies from 38% in 2000 to 59% in 2013 in adults ≥ 50 years[2]. Previously reported risks of splenic injury include female sex, advanced age, history of abdominal/pelvic surgeries, anti-platelet or anti-coagulant therapy and polypectomies/biopsies performed during colonoscopies, but it is unclear if these factors are purely associations or represent a contributing cause[3].
Even though, splenic injury is a rare complication, it is associated with significantly high mortality rate (5%)[1,4-6]. In order to ensure the timely management of splenic injuries there should be a high index of suspicion of splenic trauma in any patient presenting with severe abdominal pain and hemodynamic instability after colonoscopy. Here, we performed a systematic review to identify the risks, diagnostic factors, clinical course and management of splenic injury with colonoscopy that may help predict splenic complications after colonoscopy.
MATERIALS AND METHODS
Search strategy and selection criteria
A literature search for relevant articles was performed through April 25, 2019, using MEDLINE (PubMed, Ovid), Embase and Cochrane databases (Figure 1). There was no language or time restrictions placed on the search. The search strategies included various combinations of text-words and medical subject headings (MeSH) to generate two subsets of citations: One for spleen injury, using the MeSH and terms like “spleen rupture”, “spleen injury”, “spleen laceration”, “spleen trauma”, “spleen insult”, “spleen” and “spleen disease” and the other for colonoscopy using terms and MeSH like “colonoscopy”, “endoscopy”, “sigmoidoscopy”, “rigid colonoscopy”, “flexible endoscopy”, “rigid endoscopy”, “flexible colonoscopy”. The terms from the two subsets were combined in 1:1 combination and finally results from all the possible combinations were downloaded. Based on our research question, we also manually searched the references in all known articles to identify studies that were missed by the initial search.
The selection criteria for the included studies was: (1) Recruited subjects with any type of spleen injury secondary to colonoscopy; and (2) Discussed the mechanism, diagnosis and outcome of spleen injury. Studies with insufficient data, posters and conference papers were excluded, as were studies with not enough description of its subjects.
Study selection
The titles and abstracts of the selected articles were reviewed independently by three authors and the articles which met the inclusion criteria were reviewed by the fourth author. Full-text articles that were potentially relevant to the study were also reviewed by all the four authors to confirm the eligibility. Disagreements were resolved by mutual consensus and after a detailed group discussion.
Data abstraction and analysis
Three reviewers extracted data[3,4,7-63] (Table 1) into the excel sheet identifying the reason of colonoscopy, presentation of patient with spleen injury, types of injury, diagnosis, management and outcome of all patients with spleen injury. After carefully assessing the extracted data, all categorical data was coded into binary numbers. Frequencies and proportions were obtained for nominal and ordinal data while means and standard deviation was calculated for continuous data. Inferential statistics for categorical data was performed using Pearson Chi-square test and the alpha criterion for significance was set at a value less than 0.05. Analysis was performed using SPSS v22.
Table 1 Details of case reports and Clavein-Dindo Classification of Post-Operative complication (computed tomography).
Ref.
Age
Sex
Reason for colonoscopy
Type of injury
Diagnosis
Management
Clavein-Dindo classification of Post-Operative complication
The mean age of the patients was 62.7 (Standard deviation 15.7 years). Of the reported cases of splenic injury majority were females 64% (n = 41/64), there was no gender data available for four patients. Twenty two percent of the patients (n = 15/68) had a complete rupture of the spleen secondary to colonoscopy while the remaining 63% (n = 43/68) had a variety of spleen injuries such as subcapsular hematoma, spleen laceration and spleen avulsion. Details on the type of spleen injury was not available in 15% patients (n = 10/68). The diagnosis of any kind of spleen insult was made using the computed tomography (CT) in all patients (98.5%, n = 67/68) except one patient who was diagnosed with CT angiography.
The most common reason for colonoscopy was screening for colon cancer 46% (n = 31/68) followed by evaluation for the cause of gastrointestinal bleeding 28% (n = 19/68). Other rationales for colonoscopy were polypectomy (13%, n = 9/68), abdominal pain (3%, n = 2/68) and weight loss (1.5%, n = 1/68). There was no mention of indication of colonoscopy in 6 (9%) (Table 2).
Table 2 Reason for colonoscopy and types of injury.
Frequency
Valid percent
Colonoscopy reason
Frequency
Valid percent
Gender
Male
23
35.9
Screening
31
45.6
Female
41
64.1
Bleeding
19
27.9
Injury
Polypectomy
9
13.2
Rupture
15
22
Abdominal pain
2
2.9
Injury
43
63.2
Weight loss
1
1.5
The most common clinical presentation of splenic insult was abdominal pain either generalized or in the left hypochondrium in 87% of patients (n = 59/68). Other minor presentations included dizziness, syncope, back pain, chest pain and symptoms of anemia (Table 2, Figure 2).
Figure 2 Graphical representation of splenic injury and reason for colonoscopy.
Management in all cases was tailored according to the clinical presentation and CT scan findings. Majority of the patients required laparotomy and splenectomy 47% (n = 32/68). While patients with minor spleen hematomas and lacerations were managed conservatively with intravenous fluids, pain control and vitals monitoring 38% (n = 26/68). Interestingly, 6% (n = 4/68) patients were managed with proximal splenic artery splenic embolization (PSAE) and 4% (n = 3/68) were managed with laparoscopy. There was no outcome reported in 4.4% (n = 3/68) patients.
Despite the wide array of spleen insults ranging from mild hematoma to rupture, majority of patients survived with different management modalities. The overall mortality rate however, was significant at 10% (n = 7/68) while 77% (n = 52/68) had successful recovery. There was no outcome reported in 13% (n = 9/68) patients (Table 3).
Table 3 Presentation, diagnosis and management of splenic injury.
Presentation
Diagnosis and outcome
Management
Female
Percent (%)
Female
Percent (%)
Female
Percent (%)
Abdominal pain
59
87
CT
67
98.5
Laparotomy
32
47.1
Syncope
4
6
CTPA
1
1.5
PSAE
4
5.9
Dizziness
3
5
Survived
52
76.5
Conservative
26
38.2
Chest pain
1
1.5
Died
7
10.3
Laparoscopy
3
4.4
The reason of colonoscopy against presentation specifically abdominal pain showed no statistical significance P = 0.69. For all patients with spleen rupture and injury the most common reason was screening colonoscopy followed by colonoscopy done for gastrointestinal bleeding evaluation. This association between screening colonoscopy and spleen injury was analyzed by likelihood ratio as the number of expected count in more than 20% of the cells for more than 2 variables was less than 5. The association was robust with a value of 2.3, degree of freedom (df) of 4 but not statistically significant (P 0.667). Similarly, Chi-Square analysis and cross tabulation for the management of spleen injury was tested for any association with reason of colonoscopy. The likelihood ratio was interpreted based on the same rationale as mentioned above, there was no significant association found between the all type of colonoscopy and the management of spleen injury (splenectomy P = 0.89 and splenorrhaphy = 0.91). The alpha criteria of less than 0.05 was taken as a cutoff for significance (Figure 3).
Figure 3 Graphical representation of reason for colonoscopy and management of splenic injury.
PSAE: Proximal splenic artery splenic embolization.
To assess the association of outcome (survival/mortality) with reason of colonoscopy we cross tabulated these groups and did a chi-square test. The likelihood ratio was 3.17, df 4 and P value was not significant (screening colonoscopy 0.52, diagnostic colonoscopy 0.61) indicating there was no association between the two variables (Table 4).
Table 4 Likelihood ratios for different comparisons.
Comparison
Value
df
P value
Abdominal pain and colonoscopy
2.20
4
0.69
Spleen Injury and colonoscopy
2.37
4
0.66
Splenectomy and colonoscopy
6.4
12
0.89
Splenorrhaphy and colonoscopy
6.8
12
0.91
Outcome and screening colonoscopy
3.17
4
0.52
Outcome and diagnostic colonoscopy
3.21
4
0.61
We compared the type of spleen injury and its association with the type of management performed. It is interesting to note that 74% of the spleen rupture patients were managed with splenectomy through exploratory laparotomy. About 45% for spleen injury group had splenectomy, an equal number of patients (45%) were managed with conservative management. These results are indicating that laparotomy was a common management strategy in both groups. Only 14% patients in spleen rupture group had conservative management and PSAE due to multiple comorbidities or surgery denial. The likelihood ratio for splenectomy association with spleen rupture was 8.1, df 3 and the P value was significant at 0.04 (< 0.05). The strength of association between these variables was was moderately strong at at a cramer’s V 0.34.
The type of spleen injury was analyzed with the outcomes. An 80% of the spleen rupture and 97% of the spleen injury group survived. However, in the remaining patients, the mortality was 3 times more with spleen rupture rather than minor injury about 75% n = ¾ and 25% n = ¼ respectively. The Fisher exact test was used as in 50% cells the expected count was less than 5 and the P value was 0.028 (statistically significant) indicating higher mortality with spleen rupture. The estimate of measure size was calculated using the Phi test and it was 0.28 (< 0.3) indicating a weak association between the type of spleen rupture and mortality (Table 5, Figure 4).
Table 5 Likelihood ratios and Fisher’s test for different comparisons.
Comparison
Value
df
P value
Splenectomy and spleen rupture (Likelihood ratio)
8.1
3
0.04
Mortality and spleen rupture (Fisher’s test)
4.8
1
0.028
DISCUSSION
Colonoscopy is considered a safe procedure with low risk of complications. Common procedure related complications include perforation and bleeding[6]. A retrospective study by Levin et al[64] reported 16318 colonoscopies of which the overall complication rate was 0.5% (perforation rate 0.09%, post- biopsy/polypectomy bleeding rate 0.48%). Splenic injury after colonoscopy procedure is rare but a serious complication. During a study at a single institution, the incidence of splenic injury was 0.2 in 10000 procedures (7 out of 296248) for all the colonoscopies done between 1980 and 2008[65]. Another study reported a rate of 0.72 per 10000 procedures (12 of 165527 colonoscopies)[66]. Furthermore, a recent study by Laanani et al[10] reported an incidence of 0.20–0.34 splenic injuries per 10000 first colonoscopy procedures. The discordance of incidence rates in various reports possibly could be due to underreporting and underdiagnosis of the cases. Even though there are a few explanations for splenic trauma during colonoscopy, the mechanism is yet to be fully understood. One of the hypotheses is excessive traction on the splenocolic ligament or on splenocolic adhesions, secondary to previous abdominal surgery or intra-abdominal inflammatory processes[1,49,58,67,68]. Another possible reason could be a direct blunt trauma when navigating the colonoscope through the splenic flexure[56]. Other known risk factors for splenic trauma include older age, less experienced endoscopists, being female, polypectomy and biopsies during the procedure[1,3,5,6,69].
Nearly 2/3 of the patients (64%) with splenic trauma were females. The higher rate in females can be partly explained by the slightly better participation of women in the colorectal cancer screening process[2]. Saunders et al[70] described colonoscopy being a more complicated procedure in females compared to males because of inherently long transverse colon in females. Nonetheless, there is no evidence to support that anatomic difference could be a reason for higher incidence in females.
In our systematic review, 46% of the people that presented with splenic injury underwent colonoscopy for routine surveillance while an equal number of cases (46%) occurred when colonoscopy was done for diagnostic reasons (gastrointestinal bleed, abdominal pain, weight loss) and polypectomy together. The higher incidence in screening group can be related to increased colonoscopy rates due to public awareness[2]. In regard to the extent of injury to spleen, complete splenic rupture was seen only in 22%, whereas majority (63%) suffered a variety of spleen injuries such as sub-capsular hematoma, spleen laceration and spleen avulsion. Moreover, we did not find any association of reason for colonoscopy with either presentation, management or outcome of the patients.
In our review, CT was sensitive in diagnosing almost all cases (98.5%) of splenic trauma. This was higher than the findings of previous literature, which was 81.8%[22]. These findings reinforce the importance of performing a timely CT abdomen in all symptomatic patients suspected of post colonoscopy splenic trauma. Early diagnosis can aid in prompt management of the patients, which in turn may translate into lower mortality rate. Interestingly, until 1987 majority of splenic injuries were diagnosed during laparotomy[71,72]. It was since 1989, when CT and ultrasound came into existence, these became the major diagnostic tools[71,73]. CT is very sensitive and specific in diagnosing and grading the extent of splenic injury and thereby determines the management options. Nevertheless, the single most factor that appears to determine the management is the hemodynamic status of the patient.
Abdominal pain either generalized or in left upper quadrant was the chief complaint in most patients (85%), only 15% presented with signs of hemodynamic instability such as dizziness and syncope. Nearly half of the patients (47%) required laparotomy with splenectomy, 38% had conservative treatment (IV fluids, pain medication and blood transfusion), 4% had laparoscopy and only 6% received spleen saving splenic artery embolization. Here, we further classified management based on the degree of injury. Whereas 75% of patients with splenic rupture required laparotomy with splenectomy, the other group received either splenectomy or conservative management in equal proportions of 45% each. Here, a point worth mentioning was the favorable results shown by PSAE in grade I-II splenic injuries, though it is not widely available but reiterates the idea of increased utilization of minimally invasive treatment strategies[49,74].
The mortality rate of bleeding and perforation after colonoscopy have either trended down or stayed stable in the last few years. However, our review indicated an alarming rise in the mortality rate from splenic trauma post-colonoscopy. The overall mortality rose to 10% with 7 deaths out of 68 reviewed cases. This was twice the previously reported rate of 5.4%[56]. In addition, the mortality was 3 times higher with spleen rupture than with other forms of splenic injury. The survival rate of these groups was 80% and 97% respectively. To understand the rising mortality rates, we reviewed existing literature on the incidence of the complication but unfortunately it was limited to case reports and case series.
We could not do meta analysis as there were not enough evidence available and our review was mostly based on the individual reported cases. There were no randomized control trials or large scale observational studies available to justify further comprehensive analysis.
In conclusion, colonoscopy overall is a safer procedure and is rarely associated with splenic injuries. The incidence and management of splenic complications is not affected by the indication of colonoscopy. However, the management of spleen injury should be tailored according to the type of injury with splenectomy being reserved mostly for unstable patients with spleen rupture as it has been associated with a significantly higher mortality rate.
ARTICLE HIGHLIGHTS
Research background
Colonoscopy is a routine diagnostic and therapeutic procedure. Rarely, colonoscopy can cause splenic Injury.
Research motivation
Splenic injury is a rare but fatal complication of colonoscopy. We wanted to study the various research manuscripts published on splenic injuries during colonoscopy and find out the most common indications for colonoscopy, various presentations of patient with spleen injury, different types of injury, diagnosis and management of splenic injury.
Research objectives
The main objectives were to investigate the reason for colonoscopy, presentation of patient with spleen injury, types of injury, diagnosis, management and outcomes of patients
Research methods
A structured search on four databases was done and 45 articles with 68 patients were selected. and analyzed using SPSS. A literature search for relevant articles was performed through April 25, 2019, using MEDLINE (PubMed, Ovid), Embase and Cochrane databases. We selected manuscripts which inlcuded subjects with any type of spleen injury secondary to colonoscopy and discussed the mechanism, diagnosis and outcome of spleen injury.
Research results
We found that the mean age of the patients was 62.7 years with females predominance. Some of the patient (20%) had a complete splenic rupture, while majority (63%) had subcapsular hematoma, spleen laceration and spleen avulsion. We noticed that the most common reason for colonoscopy was screening (46%) followed by diagnostic colonoscopy (28%). Most common presentation was with abdominal pain. Patients with spleen rupture mostly required splenectomy (47%), while minor spleen hematomas and lacerations were managed conservatively (38%). Few patients (6%) were managed with proximal splenic artery splenic embolization and 4% were managed with laparoscopic repair. The overall mortality was 10% while 77% had complete recovery. Majority of the patients with splenic rupture were managed with splenectomy while the rest were managed conservatively (P = 0.04). This association was moderately strong at a cramer’s V test (0.34). The Fisher exact test showed a higher mortality with spleen rupture (P = 0.028).
Research conclusions
We found that the most common reason for colonoscopy among patients with splenic injuries was screening colonoscopy. The most common presentation was with abdominal pain. Computed tomography abdomen was diagnostic mode of choice. Majority of the patients with splenic rupture were managed with splenectomy and overall mortality was 10%. Recently, monitored anesthesia care has been used in majority of the patients for anesthesia during colonoscopy. Propofol has been used as a part of the protocol. It has been postulated that compared to conscious sedation, deep sedation is expected to blunt patient responses to painful stimuli which can lead to traumatic injuries during colonoscopy like splenic injury and perforation. Majority of the manuscripts did not have information on anesthesia protocol, which would have provided valuable information.
Research perspectives
Further studies are needed to find the likely etiology of splenic injury during. Anesthesia with propofol has been postulated to be one of the reasons for splenic injury as it might blunt patient responses to painful stimuli.
Footnotes
Manuscript source: Unsolicited manuscript
Specialty type: Gastroenterology and hepatology
Country of origin: United States
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