Definitions of Anastomosis Leak: ‘A leak of luminal contents from a surgical join between two hollow viscera’¹

The intestine plays a crucial role in nutrient absorption and overall health. Intestinal anastomosis is a common surgical procedure to restore intestinal continuity after removing a diseased portion. It can be performed using hand-sewn or stapling techniques, with hand-sewn being more common due to ease of availability and affordability. Timely intervention is essential to maintain homeostasis and ensure a healthy functional life.

The principles of the good anastomosis are adequate exposure and access, adequate blood supply of both proximal and distal bowel, avoid gross fecal contamination or sepsis, suture and proper stapler application by placing and approximation of all layer of intestinal wall, with no tension anastomosis, operative duration of less than 4 hours, and prevent distal obstruction due to narrow lumen, good nutritional condition of the patient and adequate large bowel preparation in case of elective surgery.²

Modifiable risk factors: Alcohol, Smoking, Obesity, Medication, Nutrition and Hypoalbuminaemia, Mechanical Bowel Preparation (MBP), Radiotherapy, Preoperative antibiotics and selective decontamination of the digestive tract.

Non-modifiable risk factors: Gender and age, Diabetes, Elective vs. Emergency Surgery, Tumour factors.

Early detections and modification of modifiable risk factors especially in elective settings; cumulative and clinical judgment by the surgeon, optimal preoperative care, better operative techniques, and early identification of leaks using clinical signs with biochemical markers are of principal importance in reducing anastomosis leaks. Assessment of each individual patient's risk for the leak must be made at the time of the operation and decisions regarding anastomosis and use of proximal diversion should be made accordingly³

Decision about anastomotic technique was made by the surgeon depending on his preference⁴.

1. Interrupted suture technique (IST): This technique was always performed as single-layered anastomosis with extramucosal inverting stiches using 3/0

2. Continuous suture technique (CST): For this technique single and double- layered technique was Suture material included 4/0 or 5/0 polydioxanone and 4/0 polyglyconate.

Anastomotic Configuration:⁵

There are three main anastomotic configurations used in bowel surgery. End-to-end anastomosis is used when the two bowel segments are similar in size, often in rectal resections. End-to-side anastomosis is employed when one segment is larger than the other, typically in cases of chronic obstruction. Side-to-side anastomosis creates a large, well-vascularized connection and is commonly used in ileocolic and small bowel anastomoses.

Recent Advances:

Stapler⁶ At present, a multitude of different surgical staplers can facilitate tissue closure, division, and reconstruction during open, laparoscopic, and robotic operations.

Straight staplers and linear cutters are used to seal, cut, and anastomose tubular or vascular structures, such as bowel segments and blood vessels. To unite two hollow viscera, the stapler is inserted through stab wounds in each lumen, locked, and actuated, creating a side-to-side anastomosis. The stab wounds are then closed with sutures or sealed with a straight stapler. An additional layer of hand-sewn sutures may be applied for a "two-layer" anastomosis, providing added security and peace of mind for the surgeon.

Circular staplers create an end-to-end anastomosis by inserting the staple head through a side hole in the bowel wall or through the anus. A purse-string suture is tightened around each bowel end, drawing them over the staple magazine and anvil head.

The anvil is screwed down, trapping the bowel ends, and the instrument is activated, thrusting staples through both layers and cutting off excess tissue. The instrument is then withdrawn, and the trimmed ends are examined to confirm a complete anastomosis.

The principles of anastomosis are crucial for ensuring a successful surgical outcome. To achieve this, several key considerations must be taken into account. Firstly, it is essential to ensure adequate arterial supply and venous drainage to the anastomosed site. Additionally, the anastomosis should only be performed between two disease-free ends, and it is vital to rule out any distal obstruction before joining the intestinal ends. The direction of peristaltic waves should also be carefully considered to maintain normal physiological function.

Finally, the anastomosis should be performed in a tension-free manner, without twisting or excessive constriction, to prevent complications and promote optimal healing.

Aim: To study the factors that affecting the outcome of intestinal resection and anastomosis and predispose to anastomotic leak and the measures by which these complications can be minimized and managed.

Total of 100 patients of undergoing bowel primary resection and anastomosis in various surgical units at Jawaharlal Nehru Medical College & Attached group of Hospitals, Ajmer from January 2023 to June 2024.

The relevant data was collected through a comprehensive approach, including detailed patient history, hematological and radiological investigations, intraoperative details, and post-operative information. Specifically, data was gathered on patient comorbidities, anastomosis techniques and indications and post-operative complications such as wound infections and faecal discharge. Institutional ethics committee permission was taken and patients informed consent was obtained.

Patients undergoing abdominal surgeries, either emergency or elective, involving bowel anastomosis, with a minimum age of 12 years and undergoing intestinal resection with primary anastomosis were included.

Patients under 12 years old, those undergoing initial diversion procedures or stoma closures, and those requiring combined gastrointestinal and biliary-enteric anastomosis were excluded from the study.

The study examined various pre-operative, intra-operative, and post-operative factors. Pre-operative factors, which are patient-related and non-modifiable, included age, sex, co-morbidities (diabetes, cardiac disease, renal disease), biochemical parameters (hemoglobin, albumin, renal function), previous surgery, and pre-operative hematocrit and creatinine levels.

Intra-operative factors, influenced by both patients and surgeons, were also examined. Patient-related factors included the aetiology of the condition (gangrene, malignancy, trauma) and delay in surgery. Surgeon-related factors included the type of anastomosis (end-to-end, end-to-side, side-to-side), the type of bowel involved (small-small, small-large, large-large), and the number of layers in the anastomosis (single or double layer).

Post-operative factors studied included the transfusion of blood and blood products, as well as total parenteral nutrition (TPN) transfusion. Patients were followed up for 10 days post-operatively and monitored for complications, particularly anastomotic leaks, which were assessed through abdominal drain output or after drain removal.

Patients with anastomotic leaks exhibited various signs and symptoms, including fever, severe abdominal pain, tenderness, guarding, and a silent abdomen.

They also experienced systemic symptoms such as tachycardia, hypotension, oliguria/anuria, and faecal leakage from the drain or wound, as well as prolonged ileus.

Data was collected and compiled using Microsoft Excel. P value less than 0.5 was considered as statistically significant.

In our study, 44 patients (44%) were in the 21–40-year age range, while only 4 cases (4%) were recorded in the 60 years and older category.

The mean age of the patients was 46.13±18.3 years. 59 males (59%) and 41 females (41%). 49 patients (49%) had abdominal pain. Alter bowel habit was observed in 5 (5%) patients.

Table 1: Age and sex distribution of patient undergoes intestinal anastomosis surgery

Diabetes mellitus was observed in 14 cases, anemia in 17 cases, renal disease in 10 cases, and respiratory disease in 11 cases.

Table 2: Co-morbidities of patient undergone intestinal anastomosis search

Five benign cases (5%) and 25 malignant cases (25%). In the emergency category, obstruction was identified in 31 cases (31%), while trauma was present in 14 cases (14%).

Table 3: Indication of Surgery

End to End anastomosis in 86 (86%) cases and End to Side anastomosis was in 10 (10%) cases and Side to Side anastomosis was in 4 (4%) cases.

Table 4: Type of anastomosis done in patient undergone intestinal anastomosis surgery

Wound infections were found in 12 (28%) cases and surgical site infection was found in 21 (49%) cases.

Table 5: Complications associated with patient under gone intestinal anastomosis surgery

Blood transfusions were administered in 61 cases (61%), Fresh Frozen Plasma in 30 cases (30%), and Total Parenteral Nutrition in 8 cases (8%)

Intestinal surgery, performed for various pathologies, carries a high risk of anastomotic leak⁷, a dreaded complication increasing morbidity and mortality. Leakage typically occurs between postoperative days 3-8, presenting with fever, abdominal pain, and ileus, and can progress to sepsis and hemodynamic instability^8. Modifiable and non-modifiable risk factors contribute to leaks, including age, diabetes, nutrition, anemia, and surgical techniques^9,10. Diagnostic methods include CT scans, contrast enemas, and endoscopic examinations and re-operation¹¹. Intestinal anastomotic healing relies on a delicate balance of physiological, molecular, and biochemical processes^12. Principles to minimize complications include creating tension-free joins with good blood supply^13. Management depends on clinical presentation, ranging from antibiotics and resuscitation to non-operative interventions and surgery. Recognizing risk factors and adhering to established principles is crucial for early detection and effective management of anastomotic leaks¹⁴.

The study's demographic analysis revealed a mean age of 35.58±13.40 years, with a male-to-female ratio of 59:41, similar to Puppal AN et al. (2019)¹⁵ findings. Comorbidities included diabetes (14 cases), renal disease (10 cases), and respiratory disease (11 cases), which correlated with Pujari KK et al. (2021)¹⁶ findings of similar comorbidity rates. Surgical details showed an elective-to-emergency ratio of 5:53, with 86% of anastomoses being end-to-end, 10% end-to-side, and 4% side-to-side, similar to Puppal AN et al. (2019)¹⁵ distributions and L. Srinivas (2018)¹⁷ elective-to-emergency ratio. Post-operative complications included wound infections (28%) and surgical site infections (49%), which correlated with Puppal AN et al. (2019)¹⁵ reported rates of early post-operative complications.

This study concluded that several factors negatively impact anastomotic healing, including advanced age, low albumin levels (<2gm/dl), anemia, diabetes mellitus, and uremia. These factors contribute to increased rates of wound infection, anastomotic leak, and prolonged hospital stays. Additionally, emergency surgery and poor nutritional status were found to worsen outcomes. Conversely, total parenteral nutrition (TPN) was shown to benefit patient outcomes by preventing malnutrition. Overall, optimizing nutritional status and managing comorbidities are crucial for improving surgical outcomes.

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