Percutaneous Continuous Irrigation Combined With Transgastric Necrosectomy usingLAMS in Treatment of SAP
Condition: Severe Acute Pancreatitis; Pancreatic Necrosis
MeSH terms: Pancreatitis; Pancreatitis, Acute Necrotizing; Necrosis
Study type: Observational

Summary: 
      Severe acute pancreatitis (SAP) is the most severe form of acute pancreatitis (AP) and
      Infection of pancreatic necrosis (IPN) have shown to be one of the decisive factors defining
      the severity of illness.

      Minimally invasive techniques including endoscopy, laparoscopy, retroperitoneal approaches,
      etc., have recently been widely used for debridement because the procedure can further
      reduces surgical stress and performed not require general anesthesia, thereby reducing
      complications. Studies have shown that endoscopic transgastric necrosectomy can significantly
      reduced the proinflammatory response, complications, and hospital stay. Despite these
      advantages, there are some limitations with this approach. First, transgastric necrosectomy
      should be performed as late (about 4 weeks) in the course of the disease as possible to allow
      necrosis to wrap, since early debridement may result in a higher patient fatality rate.
      However, patients with SAP are often in a severely ill state due to sepsis or MODS at an
      early stage, which causes them unable to adhere to necrotic tissue encapsulation by
      conservative treatment. Second, the ideal patient to select for this approach has necrosis
      confined in the vicinity of gastroduodenal location. Last, up to 27% of IPN patients require
      additional percutaneous catheter drainage (PCD) after undergoing endoscopic transluminal
      therapy. This may be explained by the fact that dissemination of necrosis, digestive enzymes
      and inflammatory mediators from the necrotic tissue lumen to other parts of the abdominal
      cavity during endoscopic procedures.

      Percutaneous catheter drainage (PCD) has always been the principal treatment measure for
      patients with AP at early stage (< 4 weeks) or those with collections or necrosis extending
      into deeper anatomical planes. Irrigation through peripancreatic drainage placed after open
      laparotomy has been the standard treatment for patients with AP who had undergone surgical
      necrosectomy. However, this proactive approach has not been widely used in the setting of
      PCD.

      To adequate drainage and removal of necrosis, an early percutaneous continuous irrigation
      assisted vacuum drainage in combination with subsequent endoscopic transgastric necrosectomy
      which has not been reported so far was applied in critically ill patients with SAP.
    

Detailed description: 
      Severe Acute Pancreatitis (SAP) Treatment Protocol After admission, patients were given
      intravenous analgetics, omeprazole and somatostatin, and nasojejunal tubes were placed for
      EN. Once fever developed, broad-spectrum antibiotics were given empirically. If the patient
      was concomitant with shock, respiratory failure, and acute kidney injury, appropriate organ
      support was provided. Patients with biliary pancreatitis was given encoscopic retrograde
      cholangiopancreato graphy (ERCP) within 24 h after admission. When the patient was diagnosed
      with hyperlipidemic pancreatitis and plasma triglyceride ≥11.3 mmol/L, plasma exchange was
      administered immediately. All patients were given contrast enhanced CT within 48 hours after
      admission to identify the location and range of the necrosis and calculate the CT severity
      index (CISI).

      Procedure All PCD and endoscopic procedures were performed under conscious sedation or local
      anesthesia. If the patient's condition progressively worsened, a multifunctional
      irrigation-assisted vacuum drainage tube was placed by the CT-guided Seldinger technique in
      each of the necrosis cavity. The tube was administered with continuous internal irrigation
      and vacuum drainage as described in below: (1) the end of the drainage tube (the adapter) was
      connected to a vacuum device that delivers a controlled negative pressure within the range of
      8-10 kPa. (2) a large volume of 0.9% normal saline was infused into the necrosis cavity
      constantly (1500mL a day, 65mL an hour) through the durg entrance, allowing for continuous
      irrigation; (3) the inside drainage tube was flush by rapid manual injection of 50-100 mL
      0.9% normal saline twice a day through the drug entrance and inject 20-50 mL of 0.9% normal
      saline daily through water entrance to prevent the tube from becoming blocked by necrosis,
      debris or omentum; (4) total irrigation and drainage volume were checked every 8 hours to
      keep the irrigation-drainage balanced. All tubes were checked daily and replaced when the
      tube was translocated or blocked. When the volume of irrigation exceeds the drainage 500
      mL/day or if there were serious complications associated with the drainage tube, continuous
      irrigation and vacuum drainage should be stopped immediately and the tube was the traditional
      drainage was performed.

      Approximately 4 weeks after disease onset or the formation of well-defined wall was confirmed
      by repeat CT scan, transgastric necrosectomy were performed by one or two experienced
      endoscopist under conscious sedation. Transgastric necrosectomy was repeated, mostly every
      three to five days, until all loosely adherent necrotic material were cleared and replaced by
      granulation tissue. In the course of the procedure, antibiotic administration was adjusted
      based on the results of the microbiological culture results. Subsequently, percutaneous
      irrigation was stopped and replace with simple drainage if the patient's condition continues
      to improved and the cavity confirmed by CT was resolution. If the drainage volume was less
      than 10 mL/day for 3 consecutive days, clamp the drainage tube and remove it finally.
    

Intervention name(s): Percutaneous Continuous Irrigation assisted Vacuum Drainage Combined With Transgastric Necrosectomy
Intervention type(s): Procedure
Intervention description(s): All patients with SAP were given contrast enhanced CT scan within 48 hours after admission to identify the location and range of the necrosis. If the patient's condition progressively worsened, a multifunctional irrigation-assisted vacuum drainage tube was placed by the CT-guided Seldinger technique in each of the necrosis cavity. Subsequently, transgastric necrosectomy were performed by one or two experienced endoscopist under conscious sedation. The procedure was repeated until all loosely adherent necrotic material were cleared and replaced by granulation tissue. Percutaneous irrigation was stopped and replace with simple drainage if the patient's condition continues to improved and the cavity confirmed by CT was resolution. If the drainage volume was less than 10 mL/day for 3 consecutive days, clamp the drainage tube and remove it finally.
Observational model: Case-Only
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        patients with SAP and IPN;SAP was diagnosed according to the revised Atlanta
        classification, which defined simultaneous persistent single or multiple organ failure
        >48h;IPN was considered when the following situations occur: persistent fever ≥38.5℃;
        increasing blood white blood cells (WBC), C-reactive protein (CRP) or procalcitonin; rapid
        deterioration of clinical deterioration; signs of gas was present in areas of necrosis. IPN
        is confirmed when the patient undergoes fine needle aspiration and the culture was
        positive.