Gastric and Small Bowel Motility

• Audio chapter
  Single-voice audio, listen on the commute.
• ABIM-format MCQs
  5-option vignettes with full wrong-answer teaching.
• Study guide
  Tables, decision trees, primary sources.
• AI tutor
  Chapter-grounded, answers the question you're stuck on.

What this chapter covers

• Section 8.1: Gastric motor physiology and gastroparesis pathogenesis

  Gastric emptying is a coordinated act between three systems, and gastroparesis is what happens when any one of them fails.

• Section 8.2: Gastroparesis diagnosis

  Gastroparesis cannot be diagnosed on symptoms alone because the symptoms (nausea, vomiting, early satiety, postprandial fullness, bloating, upper abdominal pain) overlap with functional dyspepsia, peptic ulcer disease, gastric outlet obstruction, cyclic vomiting syndrome, rumination, eating disorders, and chronic cannabinoid use.

• Section 8.3: Gastroparesis treatment

  Gastroparesis treatment starts with the simplest measures, and they are the most effective.

• Section 8.4: Cyclic vomiting syndrome and CHS

  Cyclic vomiting syndrome and cannabinoid hyperemesis syndrome share a striking clinical pattern of stereotyped vomiting episodes separated by symptom-free intervals, but they diverge on cause, on family history, and on treatment, and a few clues separate them.

• Section 8.5: Small bowel motility and pseudo-obstruction

  Pseudo-obstruction is the syndrome of impaired propulsive motility that mimics mechanical obstruction without an occluding lesion.

• Section 8.6: Functional dyspepsia

  Functional dyspepsia is the most common upper GI complaint in primary care and gastroenterology clinics, with a worldwide prevalence of 5 to 11 percent and up to 40 percent of affected patients seeking medical care.

Podcast episodes

1. 01

   Gastric and Small Bowel Motility: Slow Emptying

   Gastroparesis is delayed gastric emptying without a mechanical obstruction, and every cause breaks one of three things the stomach needs: an intact vagus, intact interstitial cells of Cajal, and working smooth muscle. The episode follows a man with long-standing type one diabetes, starting with causes, especially the opioids, cannabis, and GLP-1 agonists that can be fixed. Symptoms cannot make the diagnosis, so endoscopy comes first to exclude obstruction, followed by a four-hour solid-meal scintigraphy done with drugs held and glucose under two hundred. Treatment then steps up from fluids, glucose, drugs, and diet through prokinetics and antiemetics to pyloric and surgical procedures.

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2. 02

   Gastric and Small Bowel Motility: Three Syndromes

   Each syndrome in this episode is defined by a pattern, and the work is ruling out its mimics before treating by mechanism. Stereotyped vomiting attacks with symptom-free intervals are cyclic vomiting or cannabinoid hyperemesis, separated by asking about cannabis and hot showers. Obstruction without a lesion is pseudo-obstruction: exclude a mechanical cause, confirm dysmotility, separate neuropathic from myopathic disease, and search for a cause such as scleroderma or an anti-Hu paraneoplastic syndrome. Then comes supportive treatment. Functional dyspepsia is sorted into postprandial distress and epigastric pain, with alarm features and age deciding whether endoscopy comes first, and the subtype choosing the drug.

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Key topics

• ·Reservoir, pump, and pacemaker physiology of the stomach
• ·Diabetic and other causes of gastroparesis
• ·Drugs that slow gastric emptying
• ·Why symptoms cannot make the diagnosis
• ·Endoscopy before emptying study
• ·Four-hour gastric emptying scintigraphy and grading
• ·GLP-1 agonist testing pitfall
• ·Diet, glucose, and medication review
• ·Prokinetics and antiemetics
• ·Refractory disease procedures
• ·Cyclic vomiting syndrome phases and mimics
• ·Prevention and abortive therapy for cyclic vomiting
• ·Cannabinoid hyperemesis and TRPV1
• ·Chronic intestinal pseudo-obstruction workup
• ·Neuropathic versus myopathic disease and antroduodenal manometry
• ·Secondary causes: scleroderma and paraneoplastic disease
• ·Nutrition, overgrowth, and prokinetics in pseudo-obstruction
• ·Functional dyspepsia definition and subtypes
• ·Alarm features and when to scope first
• ·Subtype-directed dyspepsia treatment