Surgical considerations- summary of procedure including steps

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Gastric Resection: General

Surgical and Anesthetic

Considerations

Natalya Hasan, MD

Gastric Resections

 Indicated for Gastric CA (Adenocarcinoma - 95%; Gastrointestinal

Stromal Tumors, lymphomas, leiomyosarcomas, carcinoids, or sarcomas

-5%)

 21,000 diagnosed annually -> 10,570 yearly mortality

 5-year survival 27% between 1995 and 2005 (vs. 16% between 1975 and 1977)

 Most cancers are diagnosed at an advanced stage

Gastric Adenocarcinoma

GIST

Who gets operated on?

• For localized cancers:

• Resection + adjuvant or perioperative chemotherapy or chemoradiotherapy offers the best chance of survival

• Abdominal exploration with curative intent is undertaken

UNLESS:

• unequivocal evidence of disseminated disease

• major vascular invasion

• medical contraindications to surgery.

Surgical Considerations: Pre-Op Eval

 Pre-Op Eval is aimed at staging

Physical exam specifically lymphadenopathy (e.g. Virchow’s node), abdominal and rectal exams

 Computed tomography

 Useful for identifying distal metastases, ascites, or carcinomatosis

 Does not reliably assess the depth of tumor invasion of the stomach wall or regional nodal involvement

 Often underestimate the extent of disease, principally because of radiographically undetectable metastases involving the liver and peritoneum

Intraoperative Evaluations:

Endoscopic Ultrasound

• May provide more accurate staging evaluation of the tumor (T) and nodal (N) stage than CT and also allows for preoperative biopsies.

• Identifies pts who will benefit from neoadjuvant therapy (i.e. chemo prior to surgical treatment)

• Identifies tumors that may be amenable to endoscopic mucosal resection.

Intraoperative Evaluations:

Staging Laparoscopy

• May identify radiographically occult metastases

• Allows for direct visualization of the liver surface, peritoneum, and local lymph nodes, and permits biopsy of any suspicious lesions.

• Identifies peritoneal metastases in up to 20 to 30% of patients with a negative CT (e.g. those who would have been considered as candidates for resection)

• Pts with positive peritoneal washings but without evidence of intraperitoneal metastases can undergo neoadjuvant therapy. Laparoscopy is repeated. If repeat peritoneal washings show negative cytology, pts can then be considered candidates for resection.

Approaches

Though some superficial cancers can be treated endoscopically, gastrectomy is the most widely used approach

 Total gastrectomy - usually performed for lesions in the upper third (proximal) stomach

 Distal subtotal gastrectomy - performed for tumors in the distal (lower two-thirds) of the stomach

Gastric resections are increasingly performed laparoscopically

Overview of Open Gastric

Resection

Overview of Open Gastric Resections

 Midline incision

 Lateral segment of liver is retracted to patient’s right to expose the esophagogastric junction

 Omentum is removed from the colon

 Vessels to the stomach are individually ligated and divided

 Short gastric vessels on the greater curvature are difficult to reach

 Potential source of blood loss

 Splenic injury may occur at this time if the capsule is torn during exposure to the short gastrics

 Left gastric artery ligation can be another potential source of blood loss

 Antrum and pylorus are resected in both total and partial gastrectomy

 Lymph node dissection is typically performed

Roux en what?

After gastric resection, intestinal continuity is achieved:

 After total gastrectomy, a

Roux limb of jejunum is brought up to the distal esophagus

 After partial gastrectomy, a

Roux limb or loop of jejunum is connected to the stomach

 Anastomosis is handsewn or stapled

Mortality in the

Paleolithic Era:

100%

Current Mortality:

Total gastrectomy: 2%

Partial gastrectomy: 1%

Anesthetic Considerations

PRE-OP

 Respiratory: Identify pts with co-occurring diseases, such as COPD or asthma. Smoking history should be obtained.

Review imaging (most patients should have XRAY or CT as part of their staging workup).

 Cardiovascular: Most patients will be male and > 50 years old. Pre-op EKG is generally indicated. Pts with poor PO intake may be hypovolemic, and potentially more unstable intraoperatively.

Probably not the best candidate for surgery.

Anesthesia Pre-Op Continued

 Heme: Hypovolemia may mask anemia. CBC should be checked pre-operatively.

 EBL is 100-500 for partial gastrectomy

 500 or more for total gastrectomy.

 GI: Some pts may have GERD, delayed gastric emptying, or food contents in the lower part of their esophagus. Pre-op eval should focus on PO intake, dysphagia, GERD, etc.

Anesthetic Considerations

INTRAOPERATIVE

 Consider thoracic epidural prior to induction.

 Induction: RSI with cricoid pressure (controversial - please refer to the lecture slides dedicated to cricoid pressure)

 Maintenance: Standard. Ongoing muscle relaxation is often requested by the surgeons, especially if they are having difficulty (e.g. during exposure of the vessels or closing).

 Fluids: No consensus yet. However, running fluids in for the duration of the case is unequivocally undesirable. Please refer to slides on fluid management.

 Emergence: Anticipate extubation in most patients (except for those with underlying medical issues - e.g. COPD with FEV <1L - or in pts who have received significant volumes of IV fluids and blood products intraoperatively)

 Access: 2 large IV

 Monitoring: Standard +/- arterial line (in total gastrectomy or if indicated by pt history) +/- CVP in pts with difficult access

 Positioning: Laparoscopic - supine, Transthoracic - lateral decubitus.

Anesthetic Considerations:

Complications

• Make sure you are in communication with the surgeons during stapling.

• It is quite undesirable to staple the NG/OG (or any foreign body for that matter) into the anastomosis or within the stomach closure.

• Some surgeons are so fearful of this complication that they’ll ask you many times if EVERYTHING has been removed from the mouth (OG/NG, temp probe, bite block).

• Technically, it’s not okay to say yes (since hopefully your orotracheal tube is still in place). Preferably, you’ll state that

Everything is out of the mouth except for the orotracheal tube” after you have inspected the oral cavity with your eyes and fingers. Make sure you check behind the ETT that’s one of the temp probe’s favorite hiding places!

Speaking of Oro- and Nasogastric Tubes …

Why do we place a NGT?

Contrary to what the patient on the left would make you think, a nasogastric tube is more than just a little tube in your patient’s nose (even the mannequin looks uncomfortable).

Besides the right-main stem intubation, what else is wrong with this picture?

Oops! This can happen to you. Watch your tidal volumes when you place the NGT (or temp probe). If you’re unsure, use a laryngoscope.

Complications of NGT

 Epistaxis

 Sinusitis

 Nasal alar ulceration/necrosis

 Gastritis

 Perforation

 Aspiration (by preventing lower esophageal sphincter from closing entirely)

 Intracranial placement!

Nasogastric tubes: A little history

Nasogastric tubes have been used for over 200 years for decompression of the bowel. Until the last decade, prophylactic insertion had been considered the “standard of care” for intraabdominal operations with the intended goals of:

 gastric decompression

 decreased nausea and vomiting

 decreased distension

 decreased pulmonary aspiration and pneumonia

 decreased wound separation and infection

 decreased fascial dehiscence and hernia

 earlier return of bowel function

 earlier discharge from hospital.

Sounds great! But, a little evidence would be nice…

Prophylactic nasogastric decompression after abdominal surgery. Cochrane Database Syst Rev. 2007

• Systematic review of 33 trials (5240 patients)

• Patients randomly assigned to no nasogastric tube (early removal <24 hours after surgery included in this group) vs. standard nasogastric tube placement (up until the return of bowel function)

• “No tube group”

• Earlier return of bowel function (p<0.00001), a

• decrease in pulmonary complications (p=0.09) and an

• Insignificant trend toward increase in risk of wound infection (p=0.22) and ventral hernia (0.09).

• Decreased length of stay

• Increased vomiting

• “Tube group”

• Less vomiting, but with increased patient discomfort

• No adverse events specifically related to tube insertion

• Shortcomings:

• Reviewers remark that the “heterogeneity encountered in these analyses make rigorous conclusion difficult to draw for this outcome.

• Laparoscopic abdominal surgeries excluded

Meta-analysis of the need for nasogastric or nasojejunal decompression after gastrectomy for gastric cancer.

• Five randomized-controlled trials, 717 patients

• Randomization to routine tube vs. no tube

• Findings

• Time to oral diet was significantly shorter in the latter group

(though, on average, only a half-day sooner)

• Time to flatus, anastomotic leakage, pulmonary complications, length of hospital stay, morbidity and mortality were similar in both groups.

• Authors Conclusion: “Routine nasogastric or nasojejunal decompression is unnecessary after gastrectomy for gastric cancer.”

Assessment of routine elimination of postoperative nasogastric decompression after Roux-en-Y gastric bypass.

Background: Anastomotic disruption after surgical intervention is an infrequent complication, but may lead to severe morbidity and mortality when it occurs. Of the various gastric procedures, the Rouxen-Y gastric bypass (RYGB) has one of the highest risks for anastomotic leakage. Consequently, a nasogastric tube (NGT) is frequently placed when these operations are performed .

 Retrospective study 1067 patients, 56 had NGTs routinely placed

 No difference in the rate of leaks between the 2 groups

 Also found no increase risk of other complications (though the study has questionable power)

 Conclusions. Our findings suggest that routine placement of an NGT after RYGB is unnecessary.

Nasogastric Tubes:

Conclusions

 We’re no longer in the 1800’s (or the 1900’s for that matter)

 Likely increase pulmonary complications

 Do not speed the return of gastrointestinal function

(and may actually delay the return of function)

 Should be removed within 24 hours post-operatively.

Per our Stanford surgeons, NGT is removed on POD

#1 after gastrectomy. Exception is esophageal anastomsis (after total gastrectomy or Ivor Lewis); if swallow is functional, NGT is removed on POD 5.

 Should not be left in during stapling - pay attention!!!

References

 Huerta S, Arteaga JR, Sawicki MP, Liu CD, Livingston EH. Assessment of routine elimination of postoperative nasogastric decompression after

Roux-en-Y gastric bypass. Surgery 2002; 132:844-848.

 Jaffe Richard and Stanley Samuels. Anesthesiologist’s manual of surgical procedures. Philadelphia: Lippincott Williams and Williams,

2004.

 Mansfield, PF. Clinical features, diagnosis, and staging of gastric cancer. In: UpToDate, Tanabe, KK (Ed), UpToDage, Waltham, MA,

2011.

 Mansfield, PF. Invasive gastric cancer: Surgery and prognosis. In:

UpToDate, Tanabe, KK (Ed), UpToDage, Waltham, MA, 2011.

 Nelson R, Edwards S, Tse B. Prophylactic nasogastric decompression after abdominal surgery. Cochrane Database Syst Rev. 2007 Jul

18;(3):CD004929.

 Yang Z, Zheng Q, Wang Z. Meta-analysis of the need for nasogastric or nasojejunal decompression after gastrectomy for gastric cancer. Br J

Surg. 2008 Jul;95(7):809-16.

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