Presentation on theme: "The Scoop on Poop Grace Varas, DO Wake Forest School of Medicine"— Presentation transcript:
1The Scoop on Poop Grace Varas, DO Wake Forest School of Medicine Section on General MedicinePalliative Medicine
2The presenter has no relevant financial relationships to disclose
3Warning! Sensitive stomachs may churn, Comment est-ce possible ?Sensitive stomachs may churn,Some from the material, others from the puns!
4Objectives To understand physiology of waste elimination via bowels To recognize disorders of waste eliminationTo learn current recommendations for treatment and prophylaxis of constipationTo review the medical management of Malignant Bowel Obstructions
5Mrs. O67 yo womanOvarian cancer S/P multiple interventions, peritoneal mets, now with MBOAdmitted from acute care hospital in late October to inpatient hospice unitFamily told by previous physicians she only had “hours, maybe a day to live”Patient delirious, in distress with abd pain and nausea
6What’s It All About? The Gastrointestinal Tract: Teeth to tail: 30 feetFunction: to take in food and liquids, extract useful nutrients, and expel wasteMany enzymes, proteins, hormones, organs, and muscles in an intricate danceThe GI tract communicates with other organs (including brain)
7Let’s Start at the Very Beginning Dentition: critical to tearing and grinding food.Oropharynx: salivary glands produce digestive enzymes that begin digestive processEsophagus: first of muscular tubular structures that propels food along gi tract. (esophagus about 1 foot) Transit time: 13 seconds
8Next…..Stomach: Acids to dissolve food and continue digestion--Strong muscular organ that mixes and threshes food. Time: 2-4 hoursDuodenal bulb next.(stomach through second portion of duodenum also 1 foot)Food passes to…….
9The small intestine 20-24 ft Food moves via wave like contractions Transit 1-3 hoursThe “stuff” is still liquid as it is delivered to ….
10The large intestine Ileocecal valve to anal spincter: 4 feet Roles: To extract waterTo lubricate stoolTo pass waste to Rectum to be expelled from body.
11The colon continued…Material is transported via segmenting contractions and propagating contractionsBy 24 hours, stool has made it to transverse colonBy 48 hours, stool has made it to descending colon and sigmoid rectum
12Rectum and Anus--The End! Defecation is evacuation of fecal material from rectum. Combination of voluntary and involuntary actions.Stool fills rectum, causing distensionStraightening of anorectal angle (90 deg)Involuntary relaxation of Int Anal SphincterTo pass stool, puborectalis muscle holds angle and Ext Anal Sphincter relax
13What about Endangered Feces? What composes feces?Feces is composed primarily of water (75%)Remainder: 1/3 dead bacteria, 1/3 residue (fiber), balance: sloughed cells from intestine, bilirubin, fats, saltsWhen people don’t eat, do they still make feces? YUP.
14Don’t forget the other stuff! Digestive enzymes from salivary glands, pancreas, gallbladder, small intestineAmylase, proteases, lipase, disaccharidasesHydrochloric acidBile (liver via GB)MucusHormonesGastric secretions 2L/d
15That was the “normal stuff”… Disorders of defecation:ConstipationDiarrheaObstructionAnal diseases
16Constipation Frequent problem INDEPENDENT of Palliative Medicine! Over than 2.5 Million physician visits per year related to constipationIn elderly, over 50% using laxatives regularlyLaxative use in US: $400 MillionMore commonly reported in women (21% vs. 8% men--NHANES 1989) and blacks
17Constipation Untreated can lead to: Fecal ImpactionObstruction (megacolon)Volvulus (ischemia)ALL of which are painful and potentially life shortening!Illus from: Jacques Fabian Gautier D’Agoty, Anatomie Generale, 1752
18Rome III Criteria for Functional Constipation Symptoms ≥3 mo; onset ≥6 mo prior to diagnosisMust include ≥2 of the following:– Straining*– Lumpy or hard stools*– Sensation of incomplete evacuation*– Sensation of anorectal obstruction/blockage*– Manual maneuvers to facilitate defecation (eg, digital evacuation, support of the pelvic floor)*– <3 defecations/wkLoose stool rarely present w/o use of laxativesInsufficient criteria for IBS-CBased on: Longstreth GF et al. Gastroenterology. 2006;130:
21Obstructed defecation Outlet obstruction:cystocoele, rectocoele, anal stricture, tumor (anywhere along GI tract)Pelvic floor dys-synergyMuscular hypertonicity and spasmIncomplete relaxation of pelvic floorParadoxical contractionsThink of these when patient needs to manually help or when laxatives are ineffective
24Anal Pathology Painful conditions! Patients reluctant to pass stool, even if ableHemorrhoidsAnal FissuresStercoral ulcers (pressure ulcers within the rectum from prolonged constipation)Other anal lesions: H. zoster, tumorsTenesmus
25Constipation Delayed Transit time Main causes: inactivity, spinal cord pathology, colonic myopathyMetabolic causes: hypercalcemia, diabetes mellitus, hypothyroidismNumber one, two and three causes?DRUGS, DRUGS, DRUGS!!!!!!!
27Drugs: Our Friends, Our Foes AnticonvulsantsAnti-cancer (vinca alkaloids)Anti-cholesterol (cholestyramine)Antimony Metal Ions and MineralsAntacidsIronCalciumLead, mercury, arsenic
28Drugs: Our Friends, Our Foes Alternative medicinesChinese Green TeaGlucosamineChondroitinGingko BilobaSaw PalmettoJust about ANY medication!
29Evaluation for Constipation History of bowel movementsDrug list reviewPhysical exam of :MouthAbdomenRectumLook at environment and functional status for clues
30Managing constipation Increase fluidsIncreased activity (even just getting upright)Toileting strategies--take advantage of the gastro-colic reflex (within 20 minutes of eating)Are there barriers to having a BM? (no assistance with ambulating/transferring to BSC, fear of soiled diaper or of pain)
31Managing constipation Attempt to select/substitute less constipating drugs (eg. d/c Calcium channel blockers for another class)Consider lab work: calcium, TSHAbdominal flat plate: Constipation score0-3 in all 4 quadrants. More than a “7” calls for aggressive therapy
33Think of fecal impaction: Nausea/vomitingDeliriumTerminal restlessnessUrinary retentionDiarrheaIllus from: C.E. Bock, Atlas of the Human Body, 1879
34Drugs: Still Our Friends Opiates are BIG culprits in constipation for palliative patients:Tolerance develops to most other opioid s/e (sedation, nausea, itching), but NOT to slowing effect on transit time in the colon
35Constipation Interventions Fiber, which is helpful in the general population, may not be helpful & may actually *worsen* constipation if fluid intake is poor (<36 oz./day)Start slowly; Increase water intake with increasing fiber dosesAge Recommendations for fiber:MENWOMEN<50 y.o.38g25g>50 y.o.30g21gLivestrong.com
36Laxatives: Our Friends Stool softenersDioctyl sodium sulfsuccinate “Docusate”Decreases surface tensionWater enters stool more easilyNeed increased fluid intake to work optimally1-3 days to workIndicated with anal pathology to reduce straining
37Laxatives: Our Friends LubricantsMineral OilVaseline Balls (!)Lubricates passage1-3 days to workRisk of aspiration, malabsorption of fat-soluble vitamins
38Laxatives: Our Friends Osmotic agents:Lactulose, mannitol, sorbitol, Polyethylene glycolDraw water into stools primarily in small intestinePEG requires large volumes water1-3 days to workRisk of electrolyte shifts (i.e. cause pulmonary edema), hypomagnesemia, hyperkalemia, dehydration
39Laxatives: Our Friends Osmotic agents:Magnesium and phosphate saltsIncrease intestinal water secretion, stimulate peristalsis1-6 hoursNot considered first lineRisk of electrolyte shifts, hypermagnesemia, hyperkalemia
40Laxatives: Our Friends StimulantsPhenolic: BisacodylHydrolyzed by intestinal enzymesActs on both the small and large bowelPowerful propulsive motor activity within minutes. Risk of cramping.PO 6-12 hours to work; suppository 20 min-3hrs (avg 1 hr)
41Laxatives: Our Friends StimulantsAnthracene: SennaHydrolyzed by bacterial glycosidases in colonInduce peristalsis, increase stool water, senna some softening effectsRisk of crampingSenna alone continues to be the drug of choice for OIC prophylaxis in the literature (Twycross, et al. JPSM 2012)
42Laxatives Orally Or? If no BM > 3-4 days, gotta go from below… SuppositoriesLocal stimulationGlycerin 38% success in 1 hourBisacodyl (dulcolax)--induces peristalsis in minutes, 66% success in 1 hourAvoid in neutropenic and thrombocytopenic patients
43Laxatives Orally Or? Enemas Pure tap water--concern re: electrolyte shiftsSoap and water: irritates rectal mucosa and potential for hyperkalemiaMilk & Molasses enemas (1:1 mix)paucity of literature, but little there is shows less s/e than others, especially of electrolyte shiftC/I if milk protein allergyMy favorite to order
44Other Strategies?Methylnaltrexone (Relistor, naloxone derivative) as opioid antagonist at bowel receptorsOnly peripheral reversal, no CNSSQ injection, fairly new, $$, no long-term dataL-arginine reducing colonic slowing caused by Morphine--releases nitric oxide which works as neuromodulator in gut
45Alternative/Natural Medicines Prunes and coffeeRhubarbCascaraGinger rootLicorice rootIrish MossCayenneDandelion rootChamomile
46Selecting LaxativesSuspected obstruction? NO BULK AGENTS! =>SoftenersAnal pathology: softener to reduce strainingFecal impaction--may need disimpaction + fecal softening: glycerin, arachis, olive oilSoft feces in rectum: stimulantNo feces in rectum: stimulantOpioids: stimulant (NO tolerance shown to develop to this s/e of opioids)
47Take AwayProphylaxis is KEY for OIC“Colace (softener) without Senna (stimulant) is just mush without push”
48Anal DiseasesStool softeners the primary strategy for hemorrhoids, anal fissures, and stercoral ulcersHerpes of perineum may need aggressive treatment--aciclovir, famciclovir, but if resistant/unable po--cidofovir or foscarnet
49Malignant Bowel Obstruction Common and distressing outcome in patients with abdominal or pelvic cancer.Any time in their clinical history5.5 to 51% ovarian cancer10% to 28% colorectal cancerOther tumors: gastric, pancreatic, cervical, bladder, endometrial, mesothelial (of peritoneum), carcinoma, and melanoma
50Malignant Bowel Obstruction Causes: postoperative adhesions, a focal malignant or benign deposit, or relapse or diffuse carcinomatosis.Classic symptoms: intestinal colic, continuous abdominal pain, nausea or vomiting.Patients must be selected for surgery or medical treatment of their symptoms based on their clinical status.
51Pathophysiology of Malignant Bowel Obstruction (MBO) The goal of therapy is to normalize gut function proximal to the obstruction.The physiologic changes that arise with obstruction would be adaptive to reversible forms of bowel obstruction that may have occurred for our ancient ancestors, but they are maladaptive for patients with cancer.What "misunderstanding" arises in malignant bowel obstruction?Similarly, kidneys demonstrate a maladaptive response to heart failure. Decreased renal perfusion is sensed as dehydration. Fluid is retained to compensate when, in fact, the patient is drowning. We adjust for this by "overruling" the kidneys, telling them to get rid of salt and water and not hold on to them. The kidneys can be mistaken.
54Pathophysiology of Malignant Bowel Obstruction (MBO) A delicate balance of fluid absorption and secretion from and into the lumen is normally maintained.Studies have demonstrated that with MBO the balance is shifted strongly in favor of secretion.Increased secretion of fluid results in further intestinal dilatation, cramping, and frank nausea and vomiting.
55Pathophysiology of Malignant Bowel Obstruction (MBO) A vicious cycle is entered wherein hypersecretion (associated with cramping in the early stage) is followed by dilatation and vomiting, followed by further secretion and vomiting.Dehydration and electrolyte disturbances quickly result, leading to death (and misery) if an intervention is not made
57Traditional Medical Approaches Traditional "conservative" management, "drip and suck" therapy (IVF w/ NGT => traditional peri-operative management for obstruction)No data that supports this approach as a long-term therapy for malignant bowel obstruction.Multiple studies have shown dismal outcomes with this approach alone.Theoretically, IV hydration, in addition to restoring intravascular volume, also increases hydrostatic pressure in the villi and therefore could increase secretion into the lumen, contributing to the “vicious cycle” (distension-secretion)
58The Dynamic MBOBowel obstruction is a very dynamic process, frequently reverting from total to partial obstruction and back in as many as 50% of cases.
59Early Palliative Approaches Early palliative approaches stressed symptomatic relief.Assumed that the gut was nonfunctional, and therefore no attempt was made to normalize function.Symptomatic relief sometimes put the gut to sleep.Anticholinergic drugs both decreased secretion into the gut and decreased motility, thereby alleviating cramping.Opioids were also stressed, both to reduce motility and treat pain directly.These approaches are still used when normalization of gut function is impossible, as it often is in very proximal gut obstruction.
60Early Palliative Approaches Steroids have been used in the hope of relieving obstruction by reducing swelling around obstructing growths, although their efficacy in this regard is debatable.Only one controlled study of the use of steroids in bowel obstruction has been done. It showed no evidence that steroids were helpful in reducing the degree of obstruction. A major problem in this study was the very high rate of spontaneous conversion from total to partial obstruction.Steroids may nevertheless be useful in bowel obstruction by decreasing bowel and peritoneal inflammation and by acting as appetite stimulants.
61Recent ApproachesRecent approaches have tried to normalize gut function to the extent possible in addition to palliating symptoms directly.The ability to normalize and use the proximal gut is highly dependent on the level of obstruction.Many cases of malignant obstruction have multiple sites of obstruction, most frequently in the jejunum or ileum.
62Recent ApproachesIt is not uncommon to have many feet of potentially functional intestine proximal to the rate-limiting site of obstruction.Very proximal obstructions prohibit normalization.However, very proximal and very distal obstructions may be amenable to stent placement that results in significant palliation by forcing open the gut lumen using an expandable wire mesh stent.
63Surgical Intervention Surgical evaluation should be considered on all patients with MBO, though not all patients are candidates for surgery.Surgery carries a high perioperative mortality rate (10%–20%), high complication rate (20%–40%), and the potential for re-obstruction.Poor prognostic factors include recent laparotomy, carcinomatosis, and massive ascites.
64Surgical Intervention Relative contraindications are widespread tumor, advanced age, extra-abdominal symptomatic metastases, poor nutritional status, and previous radiotherapy.Stents can be useful for lower bowel obstruction but not for the more common higher obstructions except very proximally.A venting gastrostomy may be helpful for long-term decompression
65OctreotideAn analogue of the hormone somatostatin, it significantly reduces secretion into the gut.Study by Mangili, 13 patients with ovarian cancer-related obstruction had NG aspirate volumes measured. Mean drainage decreased from 1687 ml/day to < 50 ml/day. Similar significant results been repeated in studies by Mercadante and Shima.Somatostatin inhibits secretion of GH, TSH, ACTH and prolactin and decreases the release of gastrin, CCK, insulin, glucagon, gastric acid and pancreatic enzymes.It also inhibits neurotransmission in peripheral nerves of the GI tract leading to decreased peristalsis and a decrease in splanchnic blood flow.The most important drug in the therapy of MBO is octreotide.
66OctreotideOctreotide may prevent the pathologic alterations of bowel obstruction in cancer patients by inhibiting the release of vasointestinal peptide, reducing gastrointestinal secretion and motility, decreasing splanchnic flow, and increasing the absorption of water and salts.Octreotide is generally well tolerated. It appears to have minimal effects on motility.Dose: mcg/day, either in divided SQ q8 or in continuous dripThe most important drug in the therapy of MBO is octreotide.
67OctreotideOctreotide can result in significant improvements in nausea and vomiting; this appears to be due to decreased secretion of fluid into the gut.Improvement often occurs in 24 to 48 hours.A long-acting depo version of octreotide has been developed. (Role in chronic intermittant/MBO? $$$)The most important drug in the therapy of MBO is octreotide.
68One aggressive approach Patients received a drug combination composed of metoclopramide 60 mg/day, octreotide 0.3 mg/day (100mcg TID), and dexamethasone 12 mg daily. with hydration ( ml/d) and morphine or transdermal fentanylStudy of 29 consecutive patients with inoperable MBO, this combination produced a 90% recovery rate.The treatment not only reduced gastrointestinal symptoms (vomiting) but also allowed for the restoration of intestinal transit and re-initiation of oral feeding.Maintenance of this treatment prevented further episodes. Upon discontinuation of treatment, symptoms recurred. Patients maintained on the combination had survival prolonged from 75 days (with placebo) to 187 days.Mercadante S et al. J Pain Symptom Mgmt 2004;28:412–416
69Promotility agentsPromotility agents can be used if cramping is not present and if the intention is to normalize and use the proximal gut.Clinicians have believed that promotility agents are contraindicated in bowel obstruction traditionally because increased motility could worsen cramping and theoretically result in gut perforation.Reports of the beneficial effects of promotility drugs are beginning to appear in the literature.Care should be used with metoclopramide in the presence of renal failure, as it is renally excreted, and in patients with Parkinson's disease because of dopamine receptor blockade Experts in the field have warned that promotility drugs should not be used in complete bowel obstruction, although the evidence base for this seems weak.Since in practice it is not always easy to distinguish total from partial obstruction. Frequently, obstruction progresses from partial to total and back again, making the advice not to use promotility drugs in total obstruction easier to give in principle than to follow in practice.
70Promotility agentsMetoclopramide is the drug of choice for this purpose. Metoclopramide works by binding 5HT4 receptors and releasing acetylcholine, which in turn binds cholinergic receptors and results in increased motility.Concomitant use of drugs with anticholinergic effects, such as scopolamine, promethazine, or amitriptyline, may antagonize this action and reduce efficacy.Dosing is usually begun at 5-10 mg TID AC PO and gradually increased.For large bowel dysmotility a combination of metoclopramide with a large bowel stimulant, such as senna, will probably have to suffice until new motility agents are identified.Care should be used with metoclopramide in the presence of renal failure, as it is renally excreted, and in patients with Parkinson's disease because of dopamine receptor blockade Experts in the field have warned that promotility drugs should not be used in complete bowel obstruction, although the evidence base for this seems weak.Since in practice it is not always easy to distinguish total from partial obstruction. Frequently, obstruction progresses from partial to total and back again, making the advice not to use promotility drugs in total obstruction easier to give in principle than to follow in practice.
71Direct antiemeticsIf cramping/colic is present or if the intent is to rest the bowel, as with patients no longer capable of eating or drinking, anticholinergic and antihistaminic antiemetics such as promethazine may be used. Glycopyrrolate, a more locally acting anticholinergic drug, can be given orally or parenterally. It can reduce cramping, intestinal secretion, and nausea.If the goal is to normalize gut function, anticholinergic agents should be avoided, because they both inhibit motility and block the use of metoclopramide.5HT3 antagonists, such as ondansetron, may be the agents of choice for nausea, based on the limited data presented above suggesting 5HT3-mediated nausea and the fact that they have limited effects on motility.
72NG/venting gastrostomies NG tube placement can be very helpful for initial gut decompression.Venting gastrostomies have been used as a long-term alternative to NG tubes for decompression.No studies have compared venting gastrostomies to long-term octreotide therapy.A consensus panel of the European Association of Palliative Care recommended that venting gastrostomies be used only if medications fail to control nausea.
73Low-fiber dietMost patients with bowel obstruction who are able to eat should be on a low-fiber/low-residue diet.This is essential if they are trying to eat with a total obstruction (as is, in fact, sometimes possible).Patients with complete obstruction who do eat often vomit or regurgitate every few days.
74OpioidsOpioids are very effective in dealing with the cramping of bowel obstruction and are usually needed for pain management associated with advanced malignant disease.However, they can have undesirable effects on motility if one is trying to normalize gut function.As a general rule, pain management trumps motility management (but patient goals should be addressed)
75OpioidsThe fentanyl patch may have a lesser effect on GI motility than do other agents. It is often preferred, as well, because the oral route is generally unreliable in bowel obstruction.Methadone is also a less constipating opioid and can be administered rectally if necessary.
76Psychosocial supportPatients with distal obstruction often become distended, which alters body image and can be distressing.While most patients hate NG tubes, they can also become dependent on them and may resist suggestions to discontinue them.This may be because when they were initially placed they did provide relief. Such patients also probably fear possible tube replacement.NG Tubes, although discouraged as long-term therapy, may also represent medical caring, and thus patients and families may view suggestions to discontinue them as potential abandonment.
77Psychosocial supportThe rationale for discontinuation of any therapy must be carefully explained.The inability to eat or drink normally causes an intense grief reaction in patients and families.Adjusting the diet to a low-fiber/low-residue liquid-based one, may allow nurturing to continue even in the presence of complete bowel obstruction.
78Back to Mrs. O67 yo womanOvarian cancer S/P multiple interventions, peritoneal mets with MBOAdmitted from acute care hospital (without a PC team) in late October after a prolonged stay to inpatient hospice unit on my callPatient was delirious, in distress with abd pain and intractable nausea/vomiting. Family also in distress!
79What I did then… Octreotide 100 mcg SQ q8 hours Placed NGT to LIWS Haloperidol for nausea & deliriumDexamethasone 12 mg IV qamNS IVF (50 cc/hr)Morphine scheduled & prnReassured family we would aggresively treat her for comfort
80What happened next…NGT output initially was >1L in first 12 hours, decreased to minimal over hoursPatient awoke, comfortable, pain controlled with prn medsOn day 4, had a small BM (to the shock of family), and wanted to start drinking fluids, which I agreed to.
81What happened next…Family asked about prognosis. I told them, “Well, I don’t know if I can guarantee New Years, but certainly seems like she’ll have a place at the Thanksgiving table.”Multiple jaws hit the floor.Family told by previous physicians prior to discharge she only had “hours, maybe a day to live without surgery”
82What happened next…Patient did go on to live through Halloween, Thanksgiving, Christmas, New Years, and Valentines Day. She did require 2 short stays for recurrent MBO mgmt during this 5 month period at the inpt hospice unit. She died shortly before Easter, again under my watch.More importantly, her QOL was restored: she went on motorcycle trips with her husband, returned to a careful diet, and was pain-free most of the time. She called this her “bonus life on hospice care.”
84ReferencesSykes, N. Constipation and diarrhoea. In Doyle D, Hanks G, Cherney N, Calman K Oxford Textbook of Palliative Medicine NewYork: Oxford University Press 4th edition, 2009 Twycross, R., Sykes, N., Mihalyo, M., Wilcock, A.,“Therapeutic Reviews: Stimulant Laxatives and Opioid-Induced Constipation” Journal of Pain and Symptom Management Vol. 43 No. 2 February 2012:
85Never kick a fresh turd on a hot day. Memorable SayingsNever kick a fresh turd on a hot day.- Harry S Truman