Determining the Relative Frequency of Intestinal Obstruction Causes in Patients Referred to Ahvaz Golestan Hospital During October 2003 to 2008

Intestinal obstruction is a disruption in the forward movement of intestinal contents which can mechanically or non-mechanically involve small and large intestine. Different structures from duodenum to the anal region can be partially or completely involved. Mechanical obstruction can be induced by obstructing agents in intestinal tract, intestinal wall or by the pressure of the intestine-outside factors on the intestinal wall. Non-mechanical obstruction can be induced by abdominal surgery, pneumonia, fractured vertebrae and ribs, renal colic, radiotherapy, diabetes and medicines and mesenteric artery thrombosis. The present study aimed to investigate the causes and frequency of intestinal obstruction in patients referred to Ahvaz Golestan Hospital during October 2003 to 2008. Research method: The medical records of patients diagnosed with intestinal obstruction were studied. Finally, having finished the treatment process, 214 patients were discharged and their records were investigated according to the study’s goals and questions. In this study, 15.65% of the patients voluntarily left the hospital, 2.84% died during the treatment process, and 76.15% (214 patients) were discharged from the Hospital. In the present study, 60.3% of the patients were males and 39.7% were females. The age group of 61-75 years was the most referred age group to the Hospital. Winter showed the highest number (29.5%) of referring patients, and abdominal pain, nausea and vomiting, inability to pass gas and anorexia were the most common symptoms of patients when referring to the hospital. Finally, the patients underwent surgery and non-surgery treatments in two groups, with 45.3% undergoing surgery and 54.7% responding to supporting therapies. In the surgery group, the site of obstruction of 77.3% was in the small bowel, and that of 22.7% was in the colon. The most common causes of intestinal obstruction in the patients were adhesion of bands (52.40%), fecal impaction (13.1%), ileus (9.8%), hernia (7.5%), colon tumor (6.5%), bowel ischemia and gangrene (4.2%), rectosigmoid tumor (3.7%), volvulus (2.3%), and bezoar (0.5%). In this study, the population of male patients with bowel obstruction was more than the females. The most common cause of bowel obstruction in the referring patients was shown to be adhesion bands. The most common reason that led to surgery was adhesion bands and the most common sign that responded to the Medical Treatment was also adhesion bands. The highest figure of surgery as well as that of medical treatment belonged to the age group of 61-75 years. The causes that led to ultimate surgery had nothing to do with time, but the highest response to the medical treatment was in winter.


INTRODUCTION
Intestinal obstruction refers to any type of disruption in the passage of matters from the intestinal tract, which can be in mechanical or non-mechanical forms (1).Mechanical obstruction can involve the small intestine either completely or partially (1).One of the most common causes of abdominal surgery is intestinal surgery and one of the most common causes of intestinal surgery is intestinal obstruction (1).Small Bowel Obstruction (SBO) is more common and serious and constitutes 90% of the obstruction cases, which has led to more surgeries of the small intestine than the large intestine (4,3,2,5).Based on the anatomic relationship between obstructive lesions and the small intestine, the causes of obstruction can be classified into three categories: factors inside the intestine, factors inside the intestinal wall, factors outside the intestinal wall (1).
Bowel dilation occurs with the two ends closed, as accumulation of gas and fluid happens faster.Bowel lumen dilation occurs faster and intestinal mucosa is exposed to ischemia, necrosis, and perforation faster (6).On the other hand, gas and fluid accumulation in the proximal part to the obstruction site leads to the increased pressures inside the intestines, which causes colicky pains (7).The clinical symptoms of intestinal obstruction are different depending on the severity, duration and type of obstruction (the anatomical site of obstruction, the obstruction's being complete or partial, its being simple, gangrenous, or the two ends closed) (6).
Four main symptoms of intestinal obstruction are abdominal pain, vomiting, bowel distention, and inability to pass gas or stool (7).Simple abdominal photo is the most valuable diagnostic test of intestinal obstruction and will work in intestinal obstruction diagnosis in 50 to 60 percent of the cases (8).Other diagnostic methods of intestinal obstruction include ultrasound, CT scan, barium enema, colonoscopy, and blood test (6,1,8,3).Fifteen percent (over 300000 annual cases) of the emergency admissions include abdominal pain (6) which is one of the most important causes of mortality and high financial costs worldwide (2).Intestinal obstruction needs rapid diagnosis and emergency treatment measures so that necrosis and intestinal perforation will be more likely if intestinal obstruction is not treated rapidly.This is why surgeons give much importance to timely treatment of this disease (2,9).Since surgeries have increased due to different reasons, it is likely that intestinal obstruction prevalence is increasing in the world.In this study, all of the patients referred to Ahvaz Golestan Hospital (Iran) during October 2003 to 2008 were studied and the common and uncommon causes of intestinal obstruction were investigated and finally the patients were classified into two groups of surgery or medication treatment groups.

MATERIALS AND METHODS
The present study is a retrospective crosssectional study conducted on 281 patients who had referred to Ahvaz Golestan Hospital from October 2003 to 2008 and who had been hospitalized with primary diagnosis of intestinal obstruction.We prepared a questionnaire based on the special goals and questions of the research in order to collect the required information.The questionnaire included demographic data including patients' gender, age, type of treatment, cause of intestinal obstruction, disease symptoms, previous history of surgery, and history of chemoradiotherapy.

RESULTS
A total of 281 records related to intestinal obstruction were reviewed (129 males (60.3%) and 85 females (39.7%)).The patients under study were divided into 6 age groups (Table 1).As shown in the table, the largest number of the patients belongs to the age group of 61-75 years.The referring patients were placed in four groups in terms of the time when they had referred to the hospital (Table 2).
Winter was recognized as the season with the highest rate of patients with intestinal obstruction The patients were studied based on different symptoms they had when they had referred to the hospital, i.e. the symptoms that had helped the intestinal obstruction diagnosis in them (Table 3).
The most common symptoms of the referring patients included inability to pass gas or stool, abdominal, Nausea and vomiting, anorexia and abdominal distension (Table 3).The patients were examined in terms of colicky and non-colicky pain as well as the site of abdominal pain (Tables 4  & 5).
After examining these cases, the patients were divided into two groups of surgery treatment and non-surgery treatment (Table 6).
Among the 214 patients under study, 103 patients (48.1%) had the history of surgery, out of  7 & 8).
The most common surgery operations reported by the patients in the surgery group were appendectomy, gastrectomy, splenectomy, cholecystectomy, prostate surgery, resection, herniorrhaphy, rectosigmoid cancer, colon cancer, and laparotomy (Table 10).
In the present study, the site of intestinal obstruction in the group that had undergone surgery was in two forms based on during-surgery observation: obstruction in small intestine in 75 patients (77.3% of the patients operated upon) and in large intestine in 22 patients (22.7% of the patients that had undergone surgery operation).
The results of examining the causes of intestinal obstruction with regard to the diagnosis based on clinical signs and during-surgery observation have been shown in Table 11.
Of 214 patients with intestinal obstruction, adhesion bands was the most common cause of intestinal obstruction with 112 patients (52.4%), followed by mass stool, ileus, hernia, and colon cancer (Table 11).In next step, the frequency and distribution of the common causes of intestinal obstruction against gender were evaluated ( Table 12).
In this study, the relative frequency distributions of intestinal obstruction with the origin of small intestine that need surgery were respectively band adhesion, hernia, ischemia, intestine gangrene, and bezoar.In addition, the relative frequency distributions of intestinal obstruction with the origin of colon that need surgery were respectively colon cancer, rectosigmoid tumor, volvulus, ischemia, and intestine gangrene (Table 13).

DISCUSSION AND CONCLUSION
This study, like other similar studies, showed that the males suffering from intestinal obstruction are more than females (11,10).This can be attributed to the fact that males, compared with females, are more encountered with events such as accidents, shooting, and quarrels that resulting higher rate of surgical operations and problems such as ileus, relative obstruction, and adhesion bands.
The largest number of patients with intestinal obstruction was shown to belong to the age group 65-71 with 34.6%.due to the fact that surgical operations are more common in higher ages and also due to underlying medical diseases and reduced mobility at older ages, the mass of stool is one of the causes of intestinal obstruction in many of these patients.On the other hand, the highest rate of neoplasms at these ages can account for the largest number of intestinal obstruction in this study.
The present study showed that winter is the season with the largest number of patients (29.5% of the total patients).This may be due to the dietary habits in this season.As a larger number of the patients are at the older ages, and mobility reduces at these ages, especially at the cold seasons of the year, the incidence of intestinal obstruction in winter is more common than in other seasons of the year.
This study showed that the cause of 77.3% of the patients that had undergone surgery was small intestine, and that of 22.7% of them was colon, which was similar to the conclusions made in two other studies (12,13).The most common causes of intestinal obstruction were shown to be respectively: band adhesion with 52.4%, mass of stool with 13.1% and ileus with 98%.The age group of 61-75 years had the highest rate of surgical operations of all age groups.In addition, in the age distribution of intestinal obstruction responding to medical therapy, the age group of 61-75 years had the highest rate of medical treatment of all the age groups.
The results obtained about the time distribution of intestinal obstruction leading to surgery showed that the causes that had ultimately led to surgery had nothing to do with the time when the patients had referred to the hospital.However, the time distribution of intestinal obstruction responding to medical therapy showed that the causes that had responded to the medical therapy were related to the time when the patients had referred to the hospital, so that the highest rate of medical therapy occurred in winter.