Background and aims: Complications of endoscopy are usually under-reported. They are usually held hidden but carry a significant morbidity and sometimes mortality to the patients. Luminal perforation, bleeding and post ERCP pancreatitis are the dreaded complications of endoscopic procedures. Data on these complications is lacking from centers in developing countries. In this study, we looked at the incidence, etiology, outcome and implications of these major complications in a high-volume tertiary care teaching hospital in northern India and their context with developed countries.

Methods: A retrospective analysis of a prospectively maintained database of all endoscopic procedures done in our center from March 2000 to March 2008.

Results: Of 41,979 procedures during the period, perforations occurred in 40 cases (0.095%):  0.010% during diagnostic upper GI endoscopies, 0.014% during endoscopic injection sclerotherapy (EST), 0.12% during diagnostic colonoscopies, 0.66% during stricture dilatations, 2.16% during achalasia dilatations, and 0.48% during other miscellaneous procedures. Among 2479 ERCPs, (90% therapeutic) perforation occurred in 0.52% and clinically significant bleeding in 1.01% of the cases. All perforations in diagnostic endoscopy (n=5) occurred in elderly individuals with significant co- morbidities. Perforations, which occurred during management of esophageal varices, were with sclerotherapy and not with EVL. In achalasia dilatation, 4 of 5 perforations occurred in patients who underwent repeat procedures with larger sized balloons after a failed initial dilatation. Management of perforations was by surgery in 60% of the cases. Injection therapy sufficed to control post EPT bleed in 64%, but mortality occurred in 2 cases. Post ERCP pancreatitis occurred in 3.7% (n=91), with 0.32% (n=8) having severe pancreatitis.

Conclusion: The incidence of major post endoscopy complications in a tertiary care teaching hospital in a developing country like India is well comparable to that of all major centers in the developed world.  Unexpected complications lead to significant economic and social consequences as most patients are not covered by medical insurances and find it difficult to bear the additional cost of managing complications.

With advances in medicine and technology, endoscopy has become a widely accepted and reasonably safe modality for diagnosis as well as therapy for several gastrointestinal and pancreato-biliary disorders. In spite of its minimally invasive nature, it carries a small but definite risk of complications,¹ varying according to the patient’s condition, the nature and severity of the underlying disease, the complexity of the procedure, and the skill of the operator. The frequency of endoscopic complications is likely to rise owing to the increased number of indications for therapeutic procedures, and also to the increased complexity of endoscopic techniques.² Therapeutic third space endoscopy is akin to endoscopic surgeries done with similar rate of acceptance to complications.

Amongst many complications, Luminal perforation and major bleeding are the most dreaded complications of endoscopic procedures.^3,4 Studies have shown that diagnostic endoscopic procedures have a perforation rate of about 0.03 to 0.20%^5-7 whereas therapeutic procedures, especially endoscopic retrograde cholangiopancreatography (ERCP) carries a 0.5-1 %^8-10 risk of perforation. Various previous studies have shown the risk of post ERCP- papillotomy bleeds to be in the range of 1-2%^10,11 and mortality rates of about 0.1% due to bleeding.^8,10  All these reports are predominately from tertiary care centers situated in developed countries and indicates complication rates in advance set-ups with adequate infrastructure. The situation is different in developing countries, where volumes of procedures are high but they are sometimes conducted with limited resources, few paramedics, sparse use of anesthesia and limited ability to cope with unexpected challenges due to poor infrastructure and poor financial condition of patients. There is paucity of data on the complications encountered in developing countries, and the common assumption is that the incidence of complications is more and the outcomes are worse in these settings. There is a need for adequate information on the incidence of post endoscopy complications, the predisposing factors, challenges and outcome in such centers.  

Another common assumption is that the risk of complications would be higher in a teaching hospital where most of the procedures are performed by trainees. Although there is increasing data to suggest that the learning curve varies with the skill of the performer. There is also scarce data regarding the frequency of adverse effects occuring in the hands of trainees.^12,13

We conducted this study as a retrospective analysis of a prospectively maintained database, to look into the incidence, etiology, risk factors, mode of diagnosis, outcome and mortality rates of major endoscopic complications such as luminal perforation, bleeding and post-ERCP pancreatitis in a high volume, tertiary care teaching hospital located in northern India and compared it with the profile of complications in other centers across the globe.

The study was conducted in the department of Gastroenterology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India, a tertiary level government referral and training center in northern India, with a high volume endoscopy unit. The prospectively maintained data of all endoscopic procedures done in the endoscopy unit of the hospital over a period of 8 years from March 2000 to March 2008 was retrospectively analyzed using 2 separate sources: the endoscopy unit records as well as the centrally computerized hospital information system (HIS), a computer database which contains all patient related information, to track patients who might have reported late after an adverse event or those who reported to other departments like surgical gastroenterology or critical care department. During the study period, ten consultants and several trainees performed endoscopic procedures; including diagnostic as well as therapeutic upper and lower gastrointestinal (GI) endoscopy, stricture dilatations, ERCP, cysto-gastrostomy and other miscellaneous procedures. The procedures were done in the endoscopy unit in the hospital, with facility for three endoscopy tables functioning simultaneously, five days in a week, and also providing emergency services as and when necessary. Separate fluoroscopic equipment available within the endoscopy theatre provided the necessary fluoroscopy for ERCP. Most patients underwent ERCP under inpatient care or daycare and were discharged the next day or later providing ample time for detecting early serious complications; only few procedures such as removal of stents and diagnostic upper (GI) endoscopy were performed as day care cases. The gastroenterologists themselves administered conscious sedation for ERCP, with anesthetic backup only in seriously ill patients or those with major co-morbidities.

 For the purpose of the study, ERCP was defined as therapeutic if papillotomy /sphincterotomy (EPT) was done or if stenting, stone extraction or dilatation of a stricture was performed during the session. Perforations occurring during endoscopic procedures were defined by clinical features along with imaging modalities demonstrating extraluminal air or collections, which were not present before the procedure. Hemorrhage was considered clinically significant if there was clinical evidence of bleeding, such as melena or hematemesis, with an associated fall of hemoglobin concentration of > 2 g per deciliter, or need for a blood transfusion.⁸ Post ERCP pancreatitis was defined as new onset of pancreatic-type abdominal pain associated with at least a threefold increase in serum amylase or lipase occurring within 24 hours after an ERCP, and the pain symptoms severe enough to require admission to the hospital in patients undergoing ERCP as a day care procedure or to extend the length of stay of patients who are already hospitalized.¹⁴

The data of all the patients who had bowel perforation, pancreatitis or a significant bleed post-endoscopy were retrieved and all factors regarding the condition of the patient as well as the procedure done were noted. The baseline clinical status of the patient, including presence of co-morbidities, severity of the basic disease, and condition just prior to the procedure were looked into, to try to understand the possible contributory factors. The technical details of the procedure done were analyzed, to determine what could be the factors responsible for the adverse outcome.

Statistical analysis

The data was analyzed using SPSS 15.0 version for windows. Chi-square test was used for categorical data, with a two-tailed p value of less than 0.05 being considered significant

During the period from March 2000 to March 2008, 41,979 endoscopic procedures were performed in the endoscopy unit of the department of Gastroenterology. The breakup of the various procedures is as shown in Table 1.

Bowel perforations

Bowel perforations were encountered in 0.095% of all procedures (40 out of 41979). Achalasia cardia dilatation had the maximum risk of perforation, at 2.16%, (5 out of 231 dilatations). Perforation occurred during dilatation of esophageal strictures in 0.66% (11 out of 1669) during therapeutic ERCP in 0.52% (13 of 2479 procedures), colonoscopy (diagnostic as well as therapeutic) in 0.12% (5 out of 4247 patients) diagnostic upper GI endoscopies in 0.01%  (2 out of 18,938) and therapeutic upper GI endotherapy for esophageal varices in 0.014% (2 out of 13,997). Perforations occurred in 0.48% during miscellaneous procedures, including 2 out of 418 cystogastrostomy procedures.

The overall breakup of perforations according to etiology showed maximum number of perforations with ERCP, followed closely by stricture dilatation, as depicted in Figure 1.   

Figure 1 Etiology of Perforation during endoscopy (N=40).

Yearly trends

Even though the numbers of procedure have been increasing steadily over the years, the rate of perforation has been more or less constant, as depicted in Figure 2.

Figure 2 Yearly trends in post ERCP perforation.

Our results also showed that only 20% (n=8) of the injuries occurred in the hands of fellows during training while the rest occurred with consultants. 

Management of perforations

The median time to diagnosis of perforation in our hospital was 6 (range 1-312) hours. Of the 40 cases of perforation, diagnosis was made by plain X-rays in 19 (47.5%), gastrograffin studies in 12 (30%), contrast enhanced CT scan (CECT) in 6 patients (15%) and ultrasonography showing evidence of collections as the diagnostic study for perforation in one patient (2.5%). In 2 cases, (5%) the diagnosis was made clinically and confirmed intra operatively, when plain X-ray failed to show a definite pneumoperitoneum.

On the slightest suspicion of a complication, the surgical team was consulted, and after careful evaluation of the patient’s condition and presence of co- morbidities, a decision for conservative management (13 patients, 32.5 %) or surgery (24 patients, 60%) was taken. Three patients were advised surgery but could not be done due to lack of finances for the same. Of the 21 patients who underwent surgery, 18 (86%) recovered and 3 (14%) died. Of these three, two had comorbidities in the form of end stage kidney disease and dilated cardiomyopathy. The third death was in a young woman with esophageal perforation that occurred during dilation of a corrosive esophageal stricture. She developed severe mediastinitis and sepsis and could not be salvaged despite surgery. Of the 16 patients managed conservatively, 9 (56%) recovered, and 7 died. Although statistics showed better outcome in those operated (p=0.032), the profile of patients in the 2 groups were very different, with co-morbidities being much more in the latter. Overall, adverse outcomes occurred in 13 (33%) of 40 who developed perforation. In the subgroup analysis of the 13 patients with post-ERCP perforations, all the 5 patients who were managed conservatively and all the 5 who were taken up for emergency surgery did well. The remaining 3 patients were advised surgery, but could not arrange finances at short notice and were discharge against medical advice, are presumed to have died.

Factors leading to perforation

There are several well-recognized risk factors for perforation, and we tried to look into these risk factors in our patients who had adverse events. Five cases of perforation occurred during diagnostic procedures, 3 during diagnostic colonoscopy and 2 during upper GI endoscopy (UGIE). These patients tended to be elderly, with a mean age of 65.2 years. 4 of them had pre-existing co morbid illnesses and 2 had malignancy as the basic disease. Both the patients who had perforation after a diagnostic colonoscopy had previous history of abdominal surgery, with probable intra-abdominal adhesions, leading to difficult colonoscopy. Three other colonoscopy perforations were encountered during therapeutic colonoscopic procedures.

Two cases of perforation occurred during endotherapy for esophageal variceal bleeding; both occurred with endoscopic sclerotherapy (EST) and none with endoscopic variceal ligation (EVL). Both these patients had Child C liver disease, and both were managed conservatively due to prohibitively high risk of surgery. One patient improved, while the other had a rapid downhill course and died.

Balloon dilation for achalasia cardia was associated with 5 cases of perforation; 4 patients had perforation while using balloon of size ≥ 35 mm, all of whom were undergoing repeat procedure after initial failed dilatation. The single patient who had a perforation with a 30 mm balloon was a thin built 18-year-old girl, who had a contained perforation, which responded well to conservative management. All other patients needed emergency surgery. Dilatation of esophageal strictures led to adverse event in 11 patients, (55% males, and median age 20 years, range 1 to 50 yrs). Seven (64 %) were due to corrosive esophageal injury. Savary Gilliard (SG) dilators were used in 7 while controlled radial expansion (CRE) balloons were used in the rest. 5 strictures were in the mid esophagus, 4 in the upper and 2 in the lower esophagus. In patients with perforations occurring due to SG dilators, instruments with diameters of ≤ 15 mm were responsible for perforation in all but one case where 18 mm dilatation was done. Five perforations occurred during the initial session, while others occurred in the subsequent sessions. Thirteen cases of post ERCP perforations occurred in patients with median age of 45 years, (range 12-62 years), 9 (70%) of them were females. We tried to assess whether poor general condition of the patient, nature of underlying disease or use of needle knife precut for cannulation (which are well recognized risk factors for a post ERCP perforation) were responsible in our patients. Regarding the general condition of the patient, 3 were in cholangitis and one of them also had respiratory distress at the time of procedure, while the rest 10 perforations (77%) occurred in stable patients. Eight perforations (62%) occurred during therapy for stone disease, with the remaining 5 occurring during management of biliary strictures, either benign (n=2) or malignant (n=3). Seven out of the 13 perforations (54%) occurred in patients who needed the use of needle knife sphincterotome for precut cannulation. Two patients also had endoscopic papillotomy (EPT) bleeds, needing adrenaline injection, and post procedure, developed signs of perforation.

Post endoscopy bleeds

Hemodynamically significant bleeds occurred post procedure in 25 out of the 2479 (1.01%) patients who underwent ERCP, and in 2 cases of cysto-gastrostomy and one case of duodenal polypectomy with median age 50 years, (range 31-80 years), 15 (54%) males. Analysis of baseline parameters showed that 11 (40%) had cholangitis, 4 (14.3%) had coagulopathy, and 8 (28.6%) had poor general condition at the time they underwent the procedure. 20% were undergoing a second attempt after failed initial attempt. Needle knife precut was used to gain access to the papilla in 10 of these 25 cases, (40%). The original indication for ERCP in these patients was as given in Table 2.

The median delay in diagnosis was 4 hours; 61% patients experienced hypotension, while 75% needed blood transfusion of at least one unit. Sixteen instances of bleed (64 %) settled with adrenaline injection alone, either at the same or at a second session, while one (4%) required digital substraction angiography (DSA) and coil embolisation after failure of adrenaline to control the bleed with 6 patients (24%) went on to need for surgery. Two patients (8%) had major bleeds, not settling with adrenaline injection, one of them died within 6 hours of ERCP due to major bleed despite resuscitatory measures, while one patient who was advised surgery could not afford the same and had to be taken elsewhere due to lack of finances.

All the 3 patients who had major bleeds after cystogastrostomy or polypectemy underwent surgery with uneventful post-operative course.

Post ERCP pancreatitis

 Post ERCP pancreatitis occurred in 91 patients, was severe in 8, of whom 1 died. The incidence of post ERCP pancreatitis was 3.7%, and severe pancreatitis 0.32%. 

The overall incidence and outcomes of the major post endoscopy complications are as summarized in Table 3.

Image 1 shows major factors associated with complications in endoscopy. Despite significant advances in technology and the minimally invasive nature of endoscopy, major complications, though infrequent, continue to occur for two possible reasons. The primary reason is that more patients who are elderly, frail or sick are undergoing endoscopic procedures nowadays, and secondly a large number of procedures being performed are of therapeutic nature and involves some degree of cutting, stretching, injecting or penetrating tissues, which increases the complication risk exponentially. This is possibly one of few studies, which has attempted to audit the incidence of all major post endoscopy complications in the current era in a developing country, and have also studied its association with the underlying condition of the patient and the type and setting of procedure. 

Figure 3 Yearly trends in post ERCP perforation.

Our analysis have shown the frequency of post endoscopy perforation to be 0.095%^5,6 and that of post ERCP bleeds to be 1.01%^8,10 which were  well comparable with other published data.¹⁵ Despite the existence of various lacunae in the infrastructure which exists in a developing country, our data of complications is comparable to reports from the developed nations.^8,10 An audit of post colonoscopy complications, (but not those of other endoscopic procedures) have been published from other developing countries like Israel and Thailand, and the results are comparable to our study. The study from Israel¹⁶ showed a 0.058% incidence of perforations following colonoscopy. Western data estimates the risk to be between 0.002 to 0.19%,¹⁷ while our center has a 0.12% rate of post colonoscopy perforations. A report from Thailand¹⁸ showed a 0.09% perforation rate with colonoscopy, again similar to our results. There is only one recently published data on audit of complications during endoscopy. This particular study from Hyderabad shows, overall 0.5% adverse events during endoscopy. ERCP had 6.7% complications with 0.7% being serious. EUS having 0.05% complication rate.¹⁹

The frequency of post ERCP perforations has remained almost the same over the years, despite significant refinements in technique. An analysis done in Western centers in 1996 showed the incidence of perforations to be 0.3%⁸ while analysis done in 2008 found the rate to be 0.5%.⁹ Our study, distributed over the last 8 years, shows a 0.52% incidence of post ERCP perforations the rates being almost constant over the years. We analyzed the risks of both diagnostic and therapeutic procedures in our study. The perforations with diagnostic endoscopy occurred in elderly patients with co morbidities. Those with perforations during diagnostic colonoscopy also had previous abdominal surgery as a significant risk factor. These are well known high-risk situations for any endoscopic procedure even if the procedure is performed by the most experiencing person.^5,20 Complications with therapeutic upper GI endoscopy, especially sclerotherapy,²¹ occurred more often in patients with co morbidities (advanced liver disease) and contributed to the poor outcome in this group. Achalasia dilatation resulting in perforation occurred while using large diameter balloons and in repeat procedures after an initial failed attempt.^22,23 Perforations during dilatation of esophageal strictures mostly occurred with Savary Gillard dilators.²⁴ Previous studies done in India^25,26 have shown an incidence of (0.9-1.8%) of perforation while dilating corrosive esophageal strictures, higher than our complication rate of 0.66%.  Our complication rate is the lowest reported in this group.

 Post ERCP complications occurred more in patients who had no serious underlying co morbidities, the main risk factor for the perforation being a difficult anatomy at the papilla and the need to use a needle knife precut, as was the case in more than half of the cases. These risk factors are similar to those in other published experience^27,28 with many of the risk factors being non modifiable. Conventionally surgical management is a must in all cases of post ERCP duodenal perforations, but this was not necessary in all our patients. One third of the patients were kept on conservative management, since the patients were considered stable enough and the perforation appeared to be contained, and they all had an uneventful recovery. Previous data also support a role for such conservative management of post ERCP duodenal perforations in a select group of patients with subsequent successful outcome.^29,30

Mortality rate for post ERCP perforation was 0.12%, which is also well comparable with Western data, which ranges from 0.2-0.8%. In most of our patients, there were difficulties in management at various levels, principally due to financial constraints. Such a situation would not occur in the developed countries due to wide availability of medical insurances with the population and higher GDP expenditure over health, far ahead of India. Significant post EPT bleeds occurred in 1.01% of all ERCPs, again comparable to published series which show the risk to be 1.6-2%.^8,10 One of the previous study have shown the risk to be has high as 5.3%.³¹ Use of needle knife precut and the presence of cholangitis in 40% of our patients, are the major risk factors for post EPT bleed in our study.  Adrenaline injection continues to be the mainstay of management, with surgical options being needed in about one fourth of patients who do not respond to the same.³² Mortality rate of 0.08% is within the acceptable limits, and here again lack of finances adversely affected the situation in these patients.

Our study was conducted in a teaching hospital where the majority of procedures are done by the trainees under supervision. Despite this, the complications were found more with the high-risk procedures done by the consultants themselves. Complications occurring in very low risk patients due to inexperience of the trainees were virtually nonexistent. This shows that adequate supervision makes endoscopic training extremely safe for the patients, as seen in by other studies also.^12,13

Our study has several limitations that are intrinsic to a retrospective study. The details of the procedure and condition of the patient are not recorded uniformly in some cases, making univariate and multivariate analysis of risk factors difficult. Even though we have included all patients who presented at our center with these complications, there would be a minority who would have gone to other centers after developing complications at our center. So, the actual incidence of complications could be marginally more than these numbers. This is also within acceptable limits, since most previous studies of this nature would have the same limitation.

In the current era where several medico-legal issues are pertinent, any patient coming for an elective endoscopic procedure needs to be clearly informed about the risks and benefits of the procedure. Patient safety and minimizing the risk incidents should be an utter priority.³³ Our study is among the few that provides a comprehensive audit of complications associated with not just ERCP, but all endoscopic procedures in the current era. Other centers also need to have clear audit of their in house data and can convey it clearly to the patients who can have a clarity regarding the procedure and its adverse outcomes.

The incidence of major post endoscopy complications in a tertiary care teaching hospital in a developing country like India is well comparable to that of all major centers in the developed world.  Post endoscopy, perforations occurred in 0.095% of all endoscopic procedures and 0.52% of all ERCPs, with mortality of 0.02% for endoscopies in general and 0.12% for ERCP. Despite lack of adequate infrastructure and finances to face major complications, timely detection and aggressive management can reduce the morbidity and mortality of post procedure complications down to acceptable limits. Unexpected complications also leads to significant economic and social consequences, as most patients are not covered by medical insurances and find it difficult to bear the additional cost of managing complications

None.

None.

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