Overview
Definition:
Left adrenal sparing during distal pancreatectomy refers to a surgical technique that preserves the left adrenal gland when removing the distal portion of the pancreas
This approach is crucial for maintaining adrenal function and avoiding lifelong steroid replacement therapy, especially when the pancreatic pathology does not involve the adrenal gland.
Epidemiology:
Distal pancreatectomy is performed for various pathologies including adenocarcinoma, neuroendocrine tumors, cysts, and chronic pancreatitis of the pancreatic body and tail
The incidence of incidental adrenal involvement or the need for adrenal resection is relatively low, making adrenal sparing a feasible and desirable option in many cases.
Clinical Significance:
Preserving the left adrenal gland is vital as it is closely related anatomically to the distal pancreas and the splenic hilum
Unnecessary adrenalectomy leads to adrenal insufficiency, requiring hormone replacement with significant long-term implications for patient health and quality of life
This technique is a testament to meticulous surgical planning and execution to optimize patient outcomes.
Indications
Indications For Distal Pancreatectomy:
Malignancies of the pancreatic body and tail (e.g., adenocarcinoma, neuroendocrine tumors, IPMN)
Benign conditions like splenic cysts associated with the pancreatic tail, chronic pancreatitis, or trauma requiring distal pancreatectomy.
Indications For Adrenal Sparing:
Absence of direct tumor invasion or involvement of the left adrenal gland or its vasculature
No pre-existing adrenal pathology that necessitates resection
Tumors located exclusively in the distal pancreas without extension to the adrenal region.
Contraindications To Adrenal Sparing:
Direct gross invasion of the adrenal gland by tumor
Involvement of major adrenal vessels by tumor
Significant adrenal metastasis
Pre-existing adrenal adenoma or malignancy requiring adrenalectomy for other reasons.
Preoperative Preparation
Patient Evaluation:
Thorough history and physical examination
Comprehensive staging workup for suspected malignancies
Assessment of co-morbidities and fitness for major surgery.
Imaging Assessment:
High-resolution CT scan with contrast is essential to delineate tumor extent, assess vascular involvement (splenic vein, SMV, aorta, IVC), and evaluate the relationship of the tumor to the adrenal gland
MRI may be used for better soft tissue characterization
Angiography may be considered in select cases for vascular assessment.
Endocrine Workup:
Preoperative evaluation of adrenal function is recommended, especially if there is any doubt about involvement
Baseline cortisol levels and response to ACTH stimulation test might be considered in high-risk patients
However, for clear-cut non-invasive distal pancreatic lesions, routine extensive endocrine workup might not be necessary.
Anesthesia And Blood Products:
General anesthesia with appropriate monitoring
Availability of blood products and fluid management protocols
Consideration of intraoperative cell salvage if significant bleeding is anticipated.
Surgical Technique
Approach:
Laparoscopic or robotic approaches are increasingly preferred for distal pancreatectomy due to minimally invasive benefits
Open surgery may be required for complex cases or extensive disease.
Identification Of Adrenal Gland:
The left adrenal gland is typically located superior and posterior to the pancreas, closely related to the splenic artery and vein
Careful dissection begins by identifying the adrenal gland and its surrounding structures early in the procedure.
Dissection Around Adrenal Gland:
Meticulous dissection is performed to free the adrenal gland from the pancreatic tail and surrounding tissues
The key is to identify and meticulously ligate or divide the small adrenal vessels originating from the aorta and splenic artery, ensuring no injury to the gland or its blood supply.
Pancreatic Resection:
After mobilizing the adrenal gland, the distal pancreas is divided and resected, often along with the spleen (splenopancreatectomy)
The pancreatic stump is closed or reconstructed based on the chosen technique (e.g., pancreaticojejunostomy).
Hemostasis And Drainage:
Meticulous hemostasis is crucial throughout the procedure
Drains are typically placed in the pancreatic bed and peripancreatic area to monitor for leaks or bleeding.
Postoperative Care
Monitoring:
Close monitoring of vital signs, fluid balance, and urine output
Regular laboratory investigations including complete blood count, electrolytes, renal function, liver function tests, and amylase/lipase levels.
Pain Management:
Effective postoperative pain control is essential, often involving epidural analgesia or patient-controlled analgesia (PCA) with opioids.
Nutritional Support:
Early enteral feeding is encouraged as tolerated
Intravenous fluids and electrolytes are managed
Pancreatic enzyme supplementation may be required postoperatively.
Adrenal Function Monitoring:
Postoperative monitoring for signs of adrenal insufficiency (e.g., hypotension, hyponatremia, hyperkalemia, weakness) is critical, although typically not required if the gland was clearly spared and healthy
A baseline cortisol level may be obtained on postoperative day 1, and a stress dose steroid might be considered for major surgery, but long-term replacement is usually avoided.
Complications
Early Complications:
Pancreatic fistula (most common), hemorrhage, intra-abdominal abscess, delayed gastric emptying, wound infection, pancreatitis, bile leak, splenic vein thrombosis.
Late Complications:
Adhesibility leading to bowel obstruction, incisional hernia, malnutrition, long-term exocrine or endocrine pancreatic insufficiency (if significant pancreatic remnant is left).
Adrenal Related Complications:
Adrenal insufficiency (if inadvertent injury or removal occurs), hemorrhage from adrenal vessels if not meticulously controlled during dissection.
Key Points
Exam Focus:
The critical aspect for examinations is the anatomical relationship of the left adrenal gland to the distal pancreas and spleen, and the meticulous technique required to spare it
Understanding the indications for and contraindications of adrenal sparing is paramount.
Clinical Pearls:
Early identification of the adrenal gland during dissection is key
Thorough preoperative imaging is essential to rule out direct invasion
Meticulous ligation of small adrenal vessels minimizes bleeding risk
Preservation of the adrenal gland significantly improves long-term patient quality of life.
Common Mistakes:
Inadvertent injury or ligation of adrenal vessels leading to ischemia
Failure to adequately assess tumor extent on preoperative imaging, leading to unexpected intraoperative findings of adrenal involvement
Overly aggressive dissection leading to adrenal trauma
Not identifying the adrenal gland until late in the procedure.