AN APPROACH TO GI BLEEDING IN THE CARDIAC SURGERY PATIENT

Ryan O’Gowan, MBA, PA-C FAPACVS FCCM St. Vincent Hospital, Worcester, MA

DISCLOSURES

 I have no financial relationships with any drug or device manufacturers to disclose.

OBJECTIVES

 At the conclusion of this lecture the participant should be able to:    Describe the pathology and pathophysiology of the patient with upper and lower GI bleeding.

Outline the approach to diagnosing and treating GI bleeding, as well as clinical management.

Describe pitfalls or circumstances unique to the cardiac surgery population, as well as the literature pertaining to this population.

PATIENT SCENARIO 1

 A 68 year old cardiac surgery patient who is POD #3 presents with intractable nausea and vomiting on the telemetry unit. The patient develops pronounced hematemesis.

 Vital signs: HR 120, AF. SBP 88/60 laying flat; 78/58 sitting upright. Urine output 60cc in the last 4 hours. He is unable to stand secondary to dizziness. Respiratory rate 35, O2 Sat 89% 6LNC.

PERSPECTIVES ON MANAGEMENT

PATIENT SCENARIO 1

 Of note, the patient is an AVR with mechanical valve, has begun anticoagulation with coumadin, and has been on Amiodarone for AF.  Pre-op, the patient had an uncomplicated UTI treated with Levofloxacin.

 What is your next step in managing this patient?

APPROACH TO GI BLEEDING-SHOCK

American College of Surgeons Committee on Trauma- ATLS Course Guidebook

NEXT STEPS IN MANAGEMENT

 Remember

CAB

:  Circulation: IV Access, Crystalloid vs. Colloid Resuscitation, Central line & pressors if appropriate.

 Airway: Level of consciousness, airway assessment.

 Breathing: Use of accessory muscles, respiratory rate.

LOCALIZING THE SITE OF BLEEDING

 Not all bleeding is created alike:   Above the Ligament of Treitz  Hematemesis  Melena Below the Ligament of Treitz  Hematochezia

INITIAL MANAGEMENT

 NGT/OGT: caution in patients with known varices. +/- ice water lavage with 250cc.

 Consider Sengstaken-Blakemore tube in patients with Variceal bleeding.

 Laboratory Studies; CBC, Coags, Lactate q6-8h. Consider Serial ABGs (as base deficit may signify degree of bleeding).

 Fluid Resuscitation with blood/factor transfusions.

INITIAL MANAGEMENT

CALCULATING THE EXTENT OF BLEEDING

Blood Loss Determination:   1.) Estimate Normal Blood Volume: 66ml/kg (

♂

) or 60ml/kg (

♀

) 2.) Estimate % loss of Blood Volume:  Class 1: < 15%  Class 2: 15-30%  Class 3: 30-40%  Class 4: >40%  3.) Calculate the Volume Deficit (VD):  VD= Blood Volume (BV) x Percent Loss.

 4.) Determine the Resuscitation Volume:  VD x 1.5 for Colloids or VD x 4 for Crystalloids. The ICU Book, 3 rd Edition. Marino, et. Al.

PHARMACOLOGIC ADJUNCTS

 IV Proton Pump Inhibitors:  IV Omeprazole 20mg q12h.

 Omeprazole infusion 8mg/hr.

 Somatotatins:  Octreotide: Bolus of 25-50mcg followed by infusion of 25-50mcg/hr x 48 hours. (indicated for variceal bleeding or as an adjunct when endoscopy is not immediately available)

PHARMACOLOGIC ADJUNCTS-SPECIAL CIRCUMSTANCES  Empiric Antibiotic therapy:  Indicated for cirrhotic patients, as bacterial translocation may occur secondary to immunocompromise.

 Tranexamic Acid:  Recent studies did not show benefit of Tranexamic Acid for GI bleeding over placebo.

DIFFERENTIAL DIAGNOSIS OF UGI BLEEDING  Barret’s esophagus  Esophageal cancer  Esophagitis  Gastric Cancer  Gastric Ulcer  Gastrinoma  Mallory Weiss Tears  Variceal Disease

PATIENT SCENARIO 1-CONTINUED

 Initial labs showed a drop in the HCT to 19.9 with an INR of 3.9. Lactate was 3.1. ABG was 7.19/32/82/18 with a base deficit of -4.

 The patient was intubated, was given 3 units RBCs and 2 units FFP. An arterial line was placed, and the patient was started on pressors. GI/General Surgery were consulted and the patient was started on IV pantoprazole and Octreotide.

DIAGNOSTIC EVALUATION

 Endoscopy: Approach is determined by if bleeding is upper vs. lower.

UGI can be therapeutic and diagnostic  Electrocautery  Banding of varices  Injection of bleeding vessels with Epinephrine  CTA has an evolving role in diagnosing GI Bleeding, and may have increased utility in detecting small bowel bleeding sites.

(World J Gastroenterol. 2010 August 21; 16(31): 3957–3963.)

UGI-ELECTROCAUTERY

UGI-VARICEAL BANDING

PATIENT SCENARIO 1-CONTINUED

 UGI Endoscopy identified a small bleeding ulceration which was cauterized.  The patient continued to be transfused with RBCs and FFP. He failed to respond appropriately, as his HCT came up to 23.8, after a total of 4 Units.  The SBP went up to 180 systolic with an episode of ventilator asynchrony, and 300cc of bright red blood was suctioned out his OGT.

DIAGNOSTIC EVALUATION

 Angiography and angioembolization:  Surpassing Tagged RBC scan  Greater Utility, may also be useful in evaluating Mesenteric Ischemia if abdominal pain with elevated lactate.  Tagged RBC Scan  Requires a large volume of active blood loss to be read as positive.

 Always weigh the utility of various studies, as some may be both diagnostic and therapeutic.

POSITIVE TAGGED RBC SCAN

POSITIVE ANGIOGRAPHIC STUDY

PATIENT SCENARIO 1-CONTINUED

 The patient underwent angioembolization, of a bleeding branch of the gastro-duodenal artery, which was localized secondarily after his varices were banded.

 He was stabilized, had his Warfarin restarted, and was later referred to a specialized center for a TIPS procedure to definitively control his portal hypertension and varices.

PATIENT SCENARIO 2

 A 67 year old female S/P bare metal stenting presents with recurrent angina. She has been loaded with Plavix 300mg and has developed hematochezia. She has an IABP in place and is pre-op for CABG.

 HCT is 24.7, INR is 1.2, PLT 94,000. PRU (P2Y12 assay) shows 80% inhibition.

IDENTIFICATION OF LOWER GI BLEEDING

 Physical Exam is the first step.

 External hemorrhoids are often overlooked.

 LLQ pain may be indicative of diverticulitis, another common cause.

DIFFERENTIAL DIAGNOSIS- LGI BLEEDING

 External Hemorrhoids  Colonic polyps  Diverticulitis  Colitis (Ischemic, Ulcerative, Crohn’s)  Infectious Diarrhea (E.Coli H7:0157, Shiga toxin, Salmonella)  Anal Fissures  Neoplasm/Radiation Proctitis

PATIENT SCENARIO 2-CONTINUED

 The patient is stabilized, receives OPCAB x 3, and remains with IABP in place post op.

 On POD 2, her HCT falls to 21.3 and PLT to 55,000. She develops abdominal pain and is presently NPO. Lactate is 4.1, Creatinine is 1.7.

 What is your next priority?

COLONOSCOPY- ISCHEMIC SIGMOID COLITIS

RESUSCITATION

 Patient’s with reduced Ejection Fractions who are not intubated may require more restrictive transfusion strategies.

 The TRICC trial excluded patients with ACS and maintains a transfusion target HCT of 30.

 Reduced splanchnic flow to the kidneys and mesentery warrant increased suspicion of renal failure and mesenteric ischemia.

PATIENT SCENARIO 2-CONTINUED

 The patient is given 3 units PRBCs and 6 units Platelets- LGI bleeding continues.

 CXR reveals IABP with the tip migrated just above the renal arteries; it is repositioned and the tip is now at 4 th ICS.

 Judicious fluid resuscitation is an important element of care as the patients EF is 30%; she receives 20mg IV Lasix between the 2 nd and 3 rd unit of RBCs.

LGI ALGORITHM

PHARMACOLOGIC ADJUNCTS

 Nexium and Octreotide have been validated, but mainly in UGI bleeding, they are class B/C in LGI bleeding.

 If patients are receiving anticoagulants, Risk/Benefit must be carefully weighed before using their respective antidotes.

 Sucralfate enemas have been shown to reduce rebleeding in patients with radiation proctitis.

PATIENT SCENARIO 2-CONTINUED

 The patient is stabilized from a cardiac perspective, but continues to pass bloody stools.

 Lactate remains elevated at 3.4, and HCT does not respond appropriately to an additional 3 units RBCs- it remains low at 22.1.

 What are additional strategies that can be employed prior to GI surgery?

IMA ANGIOGRAPHY

SUPERSELECTIVE ANGIOEMBOLIZATION

PATIENT SCENARIO 2-CONTINUED

 The patient is taken to IR for superselective angioembolization.  Bleeding is stabilized temporarily, but the patient rebleeds.

 She receives another 2 units RBCs (total in last 24 hours is 8 units).

EMERGENT SURGERY

 She is taken to the OR for sigmoid colectomy and colostomy and does well post op.  Although angiograhic embolization did not stop the bleeding, the surgeon was able to localize the site more expeditiously and provide a more definitive resection.

POST OPERATIVE COMPLICATIONS

 In patients with primary re-anastamosis vs colostomy, the suture line may dehisce.

 Sepsis/Intra-abdominal abscess may present ~ POD 5, if fecal spillage occurs intra-op (peritonitis)  Abdominal Compartment Syndrome  Renal Failure  Respiratory Failure

CARDIAC SURGERY LITERATURE REVIEW

 Two of the biggest series on GI complications in cardiac surgery come from the Texas Heart Institute Journal in 2000 and 2003.

 The first is retrospective, the follow up paper is prospective.

CARDIAC SURGERY LITERATURE REVIEW



N

=4,463 patients; Retrospective Analysis. 113 GI Diagnoses in 86 patients. Prevalence 1.9%, Mortality 30%.

 Risk Factors:         Age >70 Duration of CPB Need for Blood transfusions Reoperation Triple Vessel CAD PVD NYHA Class IV CHF Use of IABP/Inotropic Support post operatively

(Tex Heart Inst J 2000;27:93-9)

CARDIAC SURGERY LITERATURE REVIEW



N

=11,058 patients; Prospective Analysis. Prevalence 1.2%, Mortality 22.5%  Complications:        UGI Hemorrhage (28.6%) Gastroesophagitis (12.2%) Intestinal Ischemia (11.5%) Mixed Gastrointestinal complications (9.5%) Pancreatitis (8.8%) Cholecystitis (6.8%) Perforated Peptic Ulcer (4.7%)

(Tex Heart Inst J 2003;30:280-5)

CARDIAC SURGERY LITERATURE REVIEW

 The cohort from the second study included CABG, Valve, Combination surgery, and Adult Congenital patients.

 Multivariate Analysis showed six independent predictors:       Prolonged mechanical ventilation Postoperative renal failure Preoperative renal failure Sepsis Sternal wound infection Valve surgery

(Tex Heart Inst J 2003;30:280-5)

GI LITERATURE REVIEW

     Meta-analysis of 200 articles from 1966-2004. Evidence Graded A, B, or C.

Incidence for LGI bleeds = 0.03% and for UGI bleeds ~1.5-3%.

For coffee ground emesis and heme (+), NG aspirate- UGI should be performed when a concomitant LGI bleed is present.

For UGI bleeds, TC-99 scanning can detect bleeding rates of 0.1ml/min; however-active bleeding is required for an effective test.

It may be prudent to electively intubate patients prior to UGI endoscopy.

(Aliment Pharmacol Ther 2005;21:1281-1298)

GI LITERATURE REVIEW

     For LGI bleeds, unless emergent, a bowel prep should take place. Non-prepped bowels increase the risk of colonic perforation of the endoscope.

It may be prudent to electively intubate patients prior to UGI endoscopy.

For LGI bleeding, angiography may be therapeutic and diagnostic, but requires bleeding rates of ~1ml/min.

Diverticular bleeds and angiodysplasia account for 50-80% of bleeding when the SMA is the bowel source.

Vasopressin infusions may control 91% of these sources (Grade B), but 50% rebleed upon cessation of the drip.

(Aliment Pharmacol Ther 2005;21:1281-1298)

GI LITERATURE REVIEW

   Transcatheter embolization using alcohol or microcoils reduces bleeding by 44-91%, however 7-40% with angiodysplasia required emergency surgery for failure or rebleed.

When angiography is successful in localizing the site, limited resection has a lower morbidity than surgery in historic controls

without

angiographic localization (8.6% vs 37%-Grade B).

Surgery is required when: hemodynamic instability persists, patients require >6 units RBCs, or severe bleeding recurs (Grade B/C).

(Aliment Pharmacol Ther 2005;21:1281-1298)

SUMMARY POINTS

      If in doubt, protect the airway.

Be vigilant for renal insufficiency and volume overload.

Be mindful in patients who don’t exhibit an appropriate response to RBCs- trend HCTs q6h.

Patients on anticoagulants may pose special challenges.

Be wary of contrast nephropathy in patients who have had CTA or Angiography.

Multidisciplinary care is key: engage GI and General Surgery early on and create a clear plan with clear accountabilities.

THANK YOU FOR YOUR TIME AND ATTENTION.

I would like to extend a special thanks to Dr. Yuka-Marie Vinagre for your review.