Abeezar I. SarelaConsultant in Upper GI & Bariatric Surgery

Hinduja Hospital, MumbaiSt James’s University Hospital, Leeds, UK

Gastric Motility Disorders

Case Study

• 52 year old woman

• Fullness after a small meal

• Continuous nausea

• 6-8 episodes of vomiting daily

• Upper abdominal bloating

• Diabetes– Insulin, Metformin, Exenatide

Endoscopy

Barium Meal and Follow-Through

CT scan

Functional Dyspepsia?

Gastroparesis

Delayed gastric emptying in

the absence of mechanical

obstruction of the stomach

True Prevalence?

25-40%

of “dyspeptic” patients

American Gastroenterological Association Technical Review on the Diagnosis and Treatment of Gastroparesis. Gastroenterology 2004;127:1592-1622

Aetiology of Gastroparesis• Idiopathic

• Diabetes mellitus

• Post-surgical– Partial gastric resection/vagotomy– Bariatric surgery– Anti-reflux surgery

• Associated with other GI disorders

• Associated with Non-GI disordersAmerican Gastroenterological Association Technical Review on the Diagnosis and

Treatment of Gastroparesis. Gastroenterology 2004;127:1592-1622

Diabetic Gastroparesis

5-12% of diabetics

Long duration of disease ~ 10 years

Neuropathy, nephropathy, retinopathy

Diabetic Gastroparesis

• Destabilisation of blood glucose control

– Alteration in drug absorption

– Unpredictable delivery of food into intestine

• Hyperglycemia affects gastric motility

• Problems with blood glucose control may

be first indication of gastroparesis

Diagnosis

Nuclear Medicine

Gastric Scintigraphy

Normal Liquid Emptying from Stomach

ExponentialCurve ~Measure

T½

Normal Emptying of Solid Food from Stomach

Normal Emptying of Solid Food from Stomach

Linear Pattern ~ Measure ProportionRetained in Stomach

At 1 hours and 4 hours

Measuring Gastric Emptying

Dual Phase Scintigraphy

Scintigraphy uses different radionuclides for labeling the liquid

and solid elements of the meal so that emptying curves for both phases are

obtained simultaneously

Normal Gastric Emptying

Normal Pattern

• Liquid phase

– T½ less < 30 minutes

• Solid phase

– at least 25% of the meal leaves the stomach

by 60 minutes

– <15% is retained in the stomach at 4 hours

Gastroparesis

solid

liquid

liquid

solid

Gastroparesis

Gastric Emptying

N Eng J Med 2007;356:820-829

Other Tests

• 13C Labelled Octanoate Breath Test

• Antroduodenal Manometry

• Electrogastrography

• Ultrasound

• Magnetic Resonance Imaging

Why is Scintigraphy the Investigation of Choice?

• Simple

• Non-invasive

• Very small radio-active dose

• Physiological

• Prolonged observation

• Quantifiable

Severity of GastroparesisMild Moderate Severe

Retention at

4 hours

10-15% 16-35% >35%

Homogenised food Rare Sometime Routine

Nutritional supplements

Rare By mouth Jejunal tube

Non-pharmacologic

treatment

No No Yes

N Eng J Med 2007;356:820-829

Treatment of Gastroparesis

1. Correction of Exacerbating Factors

2. Nutrition

Homogenised Diet

Jejunal Tube Feeding

3. Symptomatic Treatment

• Macrolides– Erythromycin

• Dopamine Receptor Antagonists– Metoclorpromide

– Erythromycin

• Anti-emetics

• Analgesia

3. Symptomatic Treatment

• Botox injection at pylorus

• Surgery

• Gastric Electrical Stimulation

Gastric Smooth Muscle Function

• Gastric slow waves (Phasic): 3/min

– Bradygastria, Tachygastria, Gastric Dysrhythmia

• Tonic spikes superimposed on slow waves result in smooth muscle contraction

Soffer et al. Aliment Pharmacol Ther 2009;30:681-694

Gastric Electrical Stimulation (GES)

Gastric Pacing:• Entrain slow waves• Low-frequency + Long duration• Implantable Pulse Generator

(IPG) not available

Implantable GES• High frequency + Short duration• Slow waves not altered• Neural stimulation

Clinically Used GES is NOT pacing

Enterra™ Therapy (Medtronics) for Gastroparesis

• Humanitarian Device Exemption approval from the US FDA in 2000

• Handheld, external programmer to adjust the neurostimulator and customize therapy

• Therapy can be turned off at any time

Electrophysiology of Enterra™ Therapy

High-Frequency stimulation with

trains of

Short-Duration pulses

Soffer et al. Aliment Pharmacol Ther 2009;30:681-694

Enterra™: Position of Electrodes

9 cm

10 cm

1 cm

Implantation of Enterra™ Electrodes

Enterra™ Therapy

• ~ 1000 devices used world-wide

• Largest experience:

– University of Mississippi Medical Centre, Jackson, USA

– ~ 600 cases

• UK

– 8 regional centres

• Improvement in one of three parameters: 90%– Health Related Quality of Life Score

• Improved to 16.3 from 10.6

– Vomiting Frequency Score • Decreased to 1.9 [0.1] from 2.9 [0.1]

– Total GI Symptom Score • Decreased to 10.9 [0.2] from 15.6 [0.3]

• Gastric Emptying– Two-hour retention fell from 55% to 42%– Four-hour retention fell from 26% to 17%

Results of Enterra™ Therapy

214 patients. 1992-2005. Univ. of Miss Med Ctr. Anand et al. Digestion 2007;75:83-89

Predictors of Poor Outcome

• Predominant symptoms: pain and bloating

• Idiopathic gastroparesis

• Loss of interstitial cells of Cahal on full thickness gastric biopsy

• Electrogastrogram: tachygastric rhythm

Endoscopy-Placed, Trans-Nasal Electrodes:

Evaluation of Response to Temporary Therapy

Gastroparesis

• Commoner than we think

• Radio-labelled scintigraphy

• Optimise diabetes treatment

• Nutrition

• Symptom-control

• Enterra™

Controversies

• Quality of evidence: Weak– Only one RCT – poor– Variable scoring systems– Attrition bias

• Confounded by concurrent pharmacotherapy

• Relationship between delayed emptying and symptoms is unclear

• Mechanism of action is unclear