Idiopathic cyclic nausea and vomiting--a disorder of gastrointestinal motility?

Cyclic Vomiting Syndrome and Cannabis Hyperemesis Syndrome: The State of the Science

This article provides a narrative review of the state of the science for both cyclic vomiting syndrome and cannabis hyperemesis syndrome along with a discussion of the relationship between these 2 conditions. The scope of this review includes the historical context of these conditions as well as the prevalence, diagnostic criteria, pathogenesis, and treatment strategies for both conditions. A synopsis of the endocannabinoid system provides a basis for the hypothesis that a lack of cannabidiol in modern high-potency Δ 9 -tetrahydrocannabinol cannabis may be contributory to cannabis hyperemesis syndrome and possibly other cannabis use disorders. In concluding assessment, though the publications addressing both adult cyclic vomiting syndrome and cannabis hyperemesis syndrome are steadily increasing overall, the state of the science supporting the treatments, prognosis, etiology, and confounding factors (including cannabis use) is of moderate quality. Much of the literature portrays these conditions separately and as such sometimes fails to account for the confounding of adult cyclic vomiting syndrome with cannabis hyperemesis syndrome. The diagnostic and therapeutic approaches are, at present, based generally on case series publications and expert opinion, with a very limited number of randomized controlled trials and a complete absence of Level 1 evidence within the cyclic vomiting literature overall as well as for cannabis hyperemesis syndrome specifically.

Cyclic vomiting syndrome: an overview for clinicians

Introduction: Cyclic vomiting syndrome (CVS) is an under recognized entity causing significant impact on patient's lifestyle. CVS is characterized by recurrent episodes of abdominal pain, nausea, and vomiting leading to many emergency department presentations prior to diagnosis. Patients often have lengthy delays in starting appropriate therapy leading to significant physical and financial hardship. Most cases of cyclic vomiting syndrome are reversible by managing risk factors and starting on appropriate treatment.Areas covered: This review covers the diagnostic criteria, pathophysiology, risk factors, and treatment for CVS and provides a valuable resource for clinicians to review and help with managing this challenging syndrome. The latest literature regarding the diagnosis and management of CVS is summarized.Expert Opinion: The direction for future research in CVS and insights to managing CVS are summarized. The role of pain that can be frequently controlled by tricyclic antidepressants and lorazepam suggests a central nervous system (CNS) origin. A standardized treatment regimen for CVS must be implemented as patients do respond to current therapies but there is often a significant delay in initiation of treatment. Reviewed recent data looking at MRI brain changes in patients with CVS that may lead to a better understanding of the pathophysiology of this disease.

Cyclic vomiting syndrome is a prevalent and under-recognized condition in the gastroenterology outpatient clinic

BACKGROUND

Cyclic vomiting syndrome (CVS) is a functional gastrointestinal disorder (FGID) characterized by intermittent episodes of nausea and vomiting. Our aim was to report its prevalence and associated features.

METHODS

Data concerning demographics, symptoms, and psychiatric comorbidity were collected. Symptoms compatible with CVS were classified as per Rome III criteria. We recorded whether a diagnosis of CVS was considered in patients after negative investigation. We compared demographics and association with other FGIDs in patients with and without CVS.

KEY RESULTS

920 of 1002 patients provided data. Of the 920 patients, 112 (12.2%) had symptoms compatible with CVS. Thirteen (11.6%) of these had an organic cause for their symptoms, but 99 patients (88.4%) were deemed to have CVS (prevalence=10.8%). Organic causes for symptoms compatible with CVS included gastroparesis, large hiatus hernia, achalasia, and small bowel obstruction. Only 39.4% of patients with CVS were asked about vomiting symptoms at their initial consultation, and a diagnosis of CVS was considered in only four (4.0%) of the 99 patients. CVS was associated with younger age, tobacco smoking, never having married, psychiatric comorbidity, and presence of symptoms compatible with other FGIDs (P≤.01).

CONCLUSIONS AND INFERENCES

Prevalence of CVS in this outpatient gastroenterology adult population was 10.8%. Identified associations included younger age, tobacco smoking, psychiatric comorbidity, and symptoms compatible with other FGIDs. The condition was considered as a possible diagnosis in <5% of patients who met the diagnostic criteria.

Cyclic vomiting syndrome: a case series and review of the literature

OBJECTIVE

Cyclic vomiting syndrome (CVS) is under-recognised. Treatment is difficult as the pathophysiology is incompletely understood. We report our experience of treating patients with amitriptyline, and review the literature to summarise symptoms and associated features, epidemiology, potential pathophysiological mechanisms, differential diagnoses and treatment.

DESIGN

Consecutive adult patients with CVS were identified during a 5-year period from January 2010 until December 2015. Medical records were reviewed retrospectively, and age and sex of the patient, symptoms, associated features and response to treatment with amitriptyline were recorded.

SETTING

A luminal gastroenterology clinic at a teaching hospital.

RESULTS

Seventeen patients were identified (mean age 29.8 years, 13 (76.5%) female). Five had a history of cannabis use. Duration of symptoms prior to diagnosis ranged from 5 months to 15 years. Fourteen patients commenced amitriptyline, and in eight (57.1%) symptoms either ceased entirely or improved. Review of the literature suggested the prevalence of CVS was 0.5%. Symptoms are stereotypical, with acute episodes of nausea and vomiting, interspersed by periods when the patient is symptom-free. Proposed pathophysiologies include neuroendocrine dysfunction, mutations in mitochondrial DNA and re-intoxication effects from cannabis stored in fat tissues. Treatment during the acute phase is supportive, with rehydration, sedation and antiemetics. Prophylaxis to prevent future attacks with antihistamines, antimigraine drugs, antiepileptics and tricyclic antidepressants may be beneficial. Complete cessation of cannabis smoking should be advised.

CONCLUSIONS

Diagnosis of CVS is often delayed in adults. Once identified, patients respond well to amitriptyline.

[Cyclic vomiting syndrome in children]

Cyclic vomiting syndrome (CVS) is a misrecognized and probably underdiagnosed disease that can affect up to 1.9% of the pediatric population and can occupy 15% of these children's time. It is characterized by acute attacks of vomiting, occurring with such a strict frequency that some parents can predict the date of their child's next attack. The pathophysiology of CVS is unclear, although the literature recognizes a common origin with migraine headaches, which has the same acute and prophylactic treatment. CVS is now included in the larger group of diseases called "episodic symptoms related to migraine" previously known as "childhood periodic syndromes." To distinguish between real CVS and other differential diagnoses can challenge the clinician. Additional investigations must be considered in accordance with the clinical presentation. Appropriate management of CVS should lead to an improvement in quality of life and school attendance.

Cannabis Hyperemesis Syndrome in the Emergency Department: How Can a Specialized Addiction Team Be Useful? A Pilot Study

BACKGROUND

Chronic cannabis users may experience cyclical episodes of nausea and vomiting and learned behavior of hot bathing. This clinical condition, known as cannabis hyperemesis syndrome, was first reported in 2004.

OBJECTIVE

Our aim was to promote early recognition of this syndrome in emergency departments (EDs) and to increase referral to addiction specialists.

METHODS

Cannabis abusers were admitted to the ED for vomiting or abdominal pain from June 1, 2014 to January 1, 2015 and diagnosed with cannabis hyperemesis syndrome by a specialized addiction team. Then, medical records were examined retrospectively.

RESULTS

Seven young adults were included. Their mean age was 24.7 years (range 17-39 years) and the majority were men (male-to-female ratio 1.2). Biological and toxicological blood samples were taken in all patients. Tetrahydrocannabinol blood level was measured in 4 patients, with a mean blood concentration of 11.6 ng/mL. Radiographic examination including abdominal computed tomography and brain imaging were negative, as was upper endoscopy. Five patients compulsively took hot baths in an attempt to decrease the symptoms. Treatment was symptomatic. Five patients have started follow-up with the specialized addiction team.

CONCLUSIONS

Cannabis hyperemesis syndrome is still under-diagnosed 10 years after it was first described. Physicians should be aware of this syndrome to avoid repeated hospitalizations or esophageal complications. Greater awareness should lead to prompt treatment and prevention of future recurrence through cannabis cessation. Addiction specialists, as well as medical toxicologists, are experts in the management of cannabis abusers and can help re-establish the role of medical care in this population in collaboration with emergency physicians.

The Vomiting Patient: Small Bowel Obstruction, Cyclic Vomiting, and Gastroparesis

Vomiting and abdominal pain are common in patients in the emergency department. This article focuses on small bowel obstruction (SBO), cyclic vomiting, and gastroparesis. Through early diagnosis and appropriate management, the morbidity and mortality associated with SBOs can be significantly reduced. Management of SBOs involves correction of physiologic and electrolyte disturbances, bowel rest and removing the source of the obstruction. Treatment of acute cyclic vomiting is primarily directed at symptom control, volume and electrolyte repletion, and appropriate specialist follow-up. The mainstay of therapy for gastroparesis is metoclopramide.

Type 1 diabetes complicated with uncontrollable adult cyclic vomiting syndrome: a case report

We herein describe the case of a 29-year-old woman with type 1 diabetes from 10 years of age who developed adult cyclic vomiting syndrome. Beginning at 25 years of age, she was frequently hospitalized for stress-induced vomiting. Her vomiting episodes developed acutely and remitted after severe vomiting of more than 30 times a day for a few days. The vomiting periods were accompanied by leukocytosis with a predominance of neutrophils, high blood pressure and fever. In addition, it was noted that her levels of both adrenocorticotropic hormone and antidiuretic hormone during the vomiting attacks increased and subsequently dramatically decreased immediately after symptom improvement; therefore, she was diagnosed with adult-type cyclic vomiting syndrome in accordance with the diagnostic criteria of Rome III, a system developed to classify functional gastrointestinal disorders. Though glycemic control had improved with continuous subcutaneous insulin infusion therapy, the vomiting frequency increased due to the failure of drug treatments and general psychotherapy to terminate the vomiting attacks, making discharge difficult and greatly interfering with everyday life. Eventually, hypnotherapy and miniature garden therapy were prescribed, which significantly reduced the vomiting frequency, making it possible to discharge her from inpatient medical care.

In the treatment of this patient with type 1 diabetes and adult-type cyclic vomiting syndrome, continuous subcutaneous insulin infusion therapy and comprehensive psychotherapy were effective.

Association of marijuana use and cyclic vomiting syndrome

Cannabis use has become one of the most commonly abused drugs in the world. It is estimated that each year 2.6 million individuals in the USA become new users and most are younger than 19 years of age. Reports describe marijuana use as high as 40–50% in male Cyclic Vomiting Syndrome patients. It is this interest in cannabis in the World, coupled with recognition of a cyclic vomiting illness associated with its chronic use that beckons a review of the most current articles, as well as a contribution from our own experiences in this area. The similarities we have demonstrated for both cannibinoid hyperemesis syndrome and cyclic vomiting make the case that cannibinoid hyperemesis syndrome is a subset of patients who have the diagnoses of cyclic vomiting syndrome and the role of marijuana should always be considered in the diagnosis of CVS, particularly in males.

Gastric stimulation for weight loss

The prevalence of obesity is growing to epidemic proportions, and there is clearly a need for minimally invasive therapies with few adverse effects that allow for sustained weight loss. Behavior and lifestyle therapy are safe treatments for obesity in the short term, but the durability of the weight loss is limited. Although promising obesity drugs are in development, the currently available drugs lack efficacy or have unacceptable side effects. Surgery leads to long-term weight loss, but it is associated with morbidity and mortality. Gastric electrical stimulation (GES) has received increasing attention as a potential tool for treating obesity and gastrointestinal dysmotility disorders. GES is a promising, minimally invasive, safe, and effective method for treating obesity. External gastric pacing is aimed at alteration of the motility of the gastrointestinal tract in a way that will alter absorption due to alteration of transit time. In addition, data from animal models and preliminary data from human trials suggest a role for the gut-brain axis in the mechanism of GES. This may involve alteration of secretion of hormones associated with hunger or satiety. Patient selection for gastric stimulation therapy seems to be an important determinant of the treatment’s outcome. Here, we review the current status, potential mechanisms of action, and possible future applications of gastric stimulation for obesity.

Review article: cyclic vomiting syndrome in adults--rediscovering and redefining an old entity

BACKGROUND

Cyclic vomiting syndrome is a disorder characterised by recurrent episodes of severe nausea and vomiting separated by symptom-free periods.

AIMS

To review the history, epidemiology, clinical aspects, pathophysiology, diagnosis and treatments of adult cyclic vomiting syndrome as well as to identify areas for further clinical research and the unanswered questions in this field.

METHODS

We conducted a PubMed search using such keywords as cyclic vomiting syndrome; nausea; vomiting; pathophysiology; diagnosis; treatment; trigger factors; gastric emptying test; autonomic nerve function test; gastrointestinal hormones; outcome and natural history and combined this information with the knowledge and extensive clinical research and publications from the authors.

RESULTS

Available data show that in adult cyclic vomiting syndrome, severe epigastric and sometimes diffuse abdominal pain accompanies most cycles of nausea and vomiting interspersed with periods of symptomatic remission. Psychological disorders, specifically anxiety and depression are common, and gastric emptying is actually rapid in approximately 60% of patients and normal in the remainder. There is an impressive and sustained response to high-dose tricyclic antidepressants. In up to 15% who are regarded as poor responders to tricyclic antidepressants, a predictable profile can be identified related to co-existing psychological disorders, marijuana use, poorly controlled migraine headache or chronic narcotic use.

CONCLUSIONS

Cyclic vomiting syndrome in adults is an entity that is being increasingly recognised, but the need to educate Internists, Gastroenterologists and Emergency Department staff remains an ongoing challenge.

Spectrum of gastric emptying patterns in adult patients with cyclic vomiting syndrome

BACKGROUND

Cyclic vomiting syndrome (CVS) in adults is a disorder characterized by recurrent and stereotypic episodes of severe nausea, vomiting and abdominal pain separated by symptom-free intervals. Both rapid and delayed gastric emptying (GE) have been observed but the reports involved small numbers of CVS patients.

METHODS

We performed a retrospective study of 92 adult patients who met Rome Ш diagnostic criteria for CVS between 2003 and 2009 at the Kansas University Medical Center. Gastric emptying was measured by a standardized scintigraphic method involving a low fat (2%) isotope labeled egg white meal of 250 Kcal, with anterior and posterior gastric imaging in the standing position obtained at 0, 1, 2, 4 h after meal ingestion. Rapid GE was defined as <50% isotope retention at 1st h and/or <30% at 2nd h and delayed GE as >10% at 4 h.

KEY RESULTS

Ninety two patients were analyzed: 47 males and 45 females mean of age 37 ± 12 years (range: 20-68 years). There were 27 patients with a personal history of migraine headache, 30 with history of marijuana use, 12 had diabetes mellitus (DM) and 10 had irritable bowel syndrome (IBS) as an accompanying diagnosis. Fifty four patients (59%) met criteria for rapid GE, 25 (27%) had normal GE and 13 (14%) had slow GE. Eighty percent of patients with co-existing IBS symptoms were identified as rapid. The subset with delayed emptying was often associated with narcotics use, DM and marijuana use (P < 0.05).

CONCLUSIONS & INFERENCES

(i) In adult CVS patients, GE is generally either rapid or normal. (ii) Cyclic vomiting syndrome is an important new etiology to explain the finding of rapid GE on a radionuclide test. (iii) The small subset of CVS patients (14%) whose GE was slow were explained by the role of narcotics and/or marijuana.

Mechanisms and potential applications of intestinal electrical stimulation

PURPOSE

Electrical stimulation of the gut has recently been under intensive investigation and various studies have revealed therapeutic potentials of gastrointestinal electrical stimulation for gastrointestinal motility disorders and obesity. While there have been a number of reviews on gastric electrical stimulation, there is a lack of systematic reviews on intestinal electrical stimulation. The aim of this review is to provide an overview on the effects, mechanisms, and applications of intestinal electrical stimulation.

RESULTS

We evaluated published data on intestinal electrophysiology, pathophysiology, and different methodologies on intestinal electrical stimulation and its possible mechanisms in both research and clinical settings using the MEDLINE database for English articles from 1963 to 2008. Based on this systematic review, intestinal electrical stimulation has been reported to alter intestinal slow waves, contractions and transit; the effects were mediated via both vagal and adrenergic pathways. Intestinal electrical stimulation has been reported to have potentials for treating various intestinal motility disorders and obesity.

CONCLUSIONS

It is concluded that intestinal electrical stimulation may have promising applications for treating motility disorders associated with altered intestinal contractile activity. The most recent studies have revealed possible applications of intestinal electrical stimulation for the treatment of obesity. Basic research results are promising; however, further clinical studies are needed to bring IES from bench to bedside.

Patients with cyclic vomiting pattern and diabetic gastropathy have more migraines, abnormal electrogastrograms, and gastric emptying

OBJECTIVE

Some patients with diabetic gastroparesis exhibit cyclical symptoms. The purpose of this work was to study the subset of patients with cyclic vomiting characteristics, described as a cyclic vomiting pattern, in a population of patients with symptoms of diabetic gastroparesis.

MATERIAL AND METHODS

Sixty-seven patients with symptoms of diabetic gastroparesis were investigated. The patients were divided into two groups based on the presence or lack of cyclic symptoms, and stratified by demographics, medical history, hemoglobin A1C, total symptom score (TSS), standardized gastric emptying test (GET), and electrogastrography (EGG).

RESULTS

Of these 67 patients, 38 (56%) had cyclic symptoms. The two groups were similar in age, gender, illness duration, insulin use, hemoglobin A1C values, and TSS. There were noteworthy differences regarding migraine headache (47.4% versus 20.7%, p=0.02), gastric emptying study (GES) at 1 h (84.1% versus 59.9%, p=0.02), EGG frequency (4.9 versus 3.6 cpm, p=0.05), and gastric emptying area under the curve (p=0.06).

CONCLUSIONS

A sizeable percentage of patients have cyclic symptom patterns and have a higher incidence of migraine headaches, a greater delay in gastric emptying, and more abnormal EGG frequencies than other patients with symptoms of diabetic gastroparesis.

Roles of interstitial cells of Cajal in regulating gastrointestinal motility: in vitro versus in vivo studies

The aim of this article is to provide a better understanding of the roles of interstitial cells of Cajal (ICC) in regulating gastrointestinal motility by reviewing in vitro and in vivo physiological motility studies. Based on the in vitro studies, ICC are proposed to have the following functions: to generate slow waves, to mediate neurotransmission between the enteric nerves and the gastrointestinal muscles and to act as mechanoreceptors. However, there is limited evidence available for these hypotheses from the in vivo motility studies. In this review, we first introduce the major subtypes of ICC and their established functions. Three Kit mutant mouse and rodent models are presented and the loss of ICC subtypes in these mutants is reviewed. The physiological motility findings from various in vitroand in vivo experiments are discussed to give a critical review on the roles of ICC in generating slow waves, regulating gastrointestinal motility, mediating neural transmission and serving as mechanoreceptors. It is concluded that the role of ICC as pacemakers may be well established, but other cells may also be involved in the generation of slow waves; the theory that ICC are mediators of neurotransmission is challenged by the majority of the in vivo motility studies; the hypothesis that ICC are mechanoreceptors has not found supportive evidence from the in vivo studies yet. More studies are needed to explain discrepancies in motility findings between the in vitro and in vivo experiments.

Roles of interstitial cells of Cajal in regulating gastrointestinal motility: in vitro versus in vivo studies

The aim of this article is to provide a better understanding of the roles of interstitial cells of Cajal (ICC) in regulating gastrointestinal motility by reviewing in vitro and in vivo physiological motility studies. Based on the in vitro studies, ICC are proposed to have the following functions: to generate slow waves, to mediate neurotransmission between the enteric nerves and the gastrointestinal muscles and to act as mechanoreceptors. However, there is limited evidence available for these hypotheses from the in vivo motility studies. In this review, we first introduce the major subtypes of ICC and their established functions. Three Kit mutant mouse and rodent models are presented and the loss of ICC subtypes in these mutants is reviewed. The physiological motility findings from various in vitro and in vivo experiments are discussed to give a critical review on the roles of ICC in generating slow waves, regulating gastrointestinal motility, mediating neural transmission and serving as mechanoreceptors. It is concluded that the role of ICC as pacemakers may be well established, but other cells may also be involved in the generation of slow waves; the theory that ICC are mediators of neurotransmission is challenged by the majority of the in vivo motility studies; the hypothesis that ICC are mechanoreceptors has not found supportive evidence from the in vivo studies yet. More studies are needed to explain discrepancies in motility findings between the in vitro and in vivo experiments.

Cyclic vomiting syndrome in adults

Cyclic vomiting syndrome (CVS) was initially described in children but can occur in all age groups. Cyclic vomiting syndrome is increasingly recognized in adults. However, the lack of awareness of CVS in adults has led to small numbers of diagnosed patients and a paucity of published data on the causes, diagnosis and management of CVS in adults. This article is a state-of-knowledge overview on CVS in adults and is intended to provide a framework for management and further investigations into CVS in adults.

Cyclic vomiting syndrome: what a gastroenterologist needs to know

BACKGROUND

CVS (cyclic vomiting syndrome) is a functional disorder that may occur in any age group of patients. In the past the disorder was considered to be fairly uncommon of unknown etiology. Treatment has generally been based on anecdotal reports.

METHODS

Literature review was performed based on internet/Medline search as of April 2006.

RESULTS

CVS is much more common than previously thought, especially in adults and is commonly associated with migraine headaches and sharing many of its characteristic features. Genetic association with mitochondrial DNA has been recognized with CVS. Prompt diagnosis is essential in order to prevent the significant morbidity associated with CVS. It is mandatory to rule out certain life-threatening disorders that can mimic CVS. Treatment options are based on the particular phase of the syndrome in which a patient is in and carried out in a systematic manner.

CONCLUSION

Expert consensus is that CVS is a distinct disorder and is a part of the migraine spectrum (migraine headaches, CVS, and abdominal migraines). Once patients are properly diagnosed, treatment is highly effective. Because of renewed interest in CVS since the 1990's, many more patients in all age groups are being recognized who suffer from this disabling disorder. An increase in basic science and clinical research in CVS will hopefully lead to better patient outcomes.

Gastroparesis: symptoms, evaluation, and treatment

Gastroparesis presents with gastrointestinal symptoms and nongastrointestinal manifestations in association with objective delays in gastric emptying. The condition may complicate several systemic disorders or may be idiopathic in nature. The diagnosis is made by directed evaluation to exclude organic diseases, which can mimic the clinical presentation of gastroparesis coupled with quantification of gastric emptying. Current therapies rely on dietary modifications, medications to stimulate gastric evacuation, and agents to reduce vomiting. Endoscopic and surgical options are increasingly used for cases refractory to medication treatment.

Roles of putative neurotransmitters in the regulation of gastric and intestinal slow waves in conscious dogs

BACKGROUND AND AIMS

Slow waves play an important role in controlling the frequency and propagation of gastrointestinal contractions. However, mechanisms involved in the modulation of slow wave activity in vivo are still unclear. In this study, the roles of different neurotransmitters in the regulation of gastrointestinal slow waves were investigated in conscious dogs.

METHODS

Female dogs implanted with electrodes in the stomach and the small bowel were used in a seven-session study. Gastrointestinal myoelectrical activity was recorded at baseline and after i.v. saline, atropine, atropine methyl nitrate, guanethidine, Nomega-nitro-L-arginine (L-NNA), ondansetron or naloxone.

RESULTS

Both atropine and atropine methyl nitrate induced tachygastria, bradygastria and arrhythmia. No difference was noted in the effects between atropine and atropine methyl nitrate. L-NNA increased the dominant frequency of small-intestinal slow waves but had no effect on gastric slow waves. Guanethidine, ondansetron and naloxone did not affect the dominant frequency, power or percentage of normal gastrointestinal slow waves.

CONCLUSION

Acetylcholine acting at muscarinic receptors seems to play an important role in the regulation of gastric slow waves. Nitric oxide may play a role in modulating intestinal slow waves but not gastric slow waves. Sympathetic pathways, 5-HT(3) receptors and opioid receptors (especially micro-opioid receptors) do not play a role in the regulation of gastric or intestinal slow waves under normal physiological conditions.

Relief of acute pain in chronic idiopathic gastroparesis with intravenous phentolamine

OBJECTIVE

To report a case in which complete relief of pain associated with gastroparesis, with promotion of gastric emptying, was achieved with administration of phentolamine.

CASE SUMMARY

A 37-year-old opiate-tolerant female with a history of recurrent abdominal pain, gastroparesis, cyclic vomiting syndrome, and migraine headaches was admitted to the emergency department (ED) with severe acute abdominal pain, nausea, and vomiting. The patient had been previously implanted with a permanent gastric electrical stimulator and she was adherent to her prokinetic, antiemetic, analgesic, and migraine prophylactic medications. Pain relief was achieved rapidly and completely in the ED with sympatholysis by administration of intravenous phentolamine 0.5 mg/kg over 60 minutes, with continuous cardiac monitoring. At a 2 month follow-up visit, the patient reported chronic pain relief, and a decrease in opiate doses was maintained by oral administration of clonidine 0.1 mg twice daily.

DISCUSSION

Gastroparesis represents a difficult treatment challenge because management of gastric dysmotility and the accompanying severe abdominal pain is often mutually exacerbating and ineffective. Sympatholysis by intravenous phentolamine provided profound and immediate relief of acute gastroparesis-related abdominal pain in our patient. The mechanism of phentolamine is believed to be receptor blockade at alpha-adrenergic receptors and, therefore, inhibition of the peripheral sensitizing effects of circulating norepinephrine. Although action at a peripheral nerve level is presumed, modulation of alpha-adrenoreceptors receptors is also possible at the dorsal root ganglion or at other central nervous system sites.

CONCLUSIONS

The dramatic relief of acute pain in gastroparesis by phentolamine observed in this case would warrant investigation of a larger, controlled case series. Patients who respond to intravenous sympatholysis may likewise be candidates for longer term sympathetic modulation with oral sympatholytics.

Signals for nausea and emesis: Implications for models of upper gastrointestinal diseases

Nausea and vomiting are amongst the most common symptoms encountered in medicine as either symptoms of diseases or side effects of treatments. In a more biological setting they are also important components of an organism's defences against ingested toxins. Identification of treatments for nausea and vomiting and reduction of emetic liability of new therapies has largely relied on the use of animal models, and although such models have proven invaluable in identification of the anti-emetic effects of both 5-hydroxytryptamine(3) and neurokinin(1) receptor antagonists selection of appropriate models is still a matter of debate. The present paper focuses on a number of controversial issues and gaps in our knowledge in the study of the physiology of nausea and vomiting including: The choice of species for the study of emesis and the underlying behavioural (e.g. neophobia), anatomical (e.g. elongated, narrow abdominal oesophagus with reduced ability to shorten) and physiological (e.g. brainstem circuitry) mechanisms that explain the lack of a vomiting reflex in certain species (e.g. rats); The choice of response to measure (emesis[retching and vomiting], conditioned flavour avoidance or aversion, ingestion of clay[pica], plasma hormone levels[e.g. vasopressin], gastric dysrhythmias) and the relationship of these responses to those observed in humans and especially to the sensation of nausea; The stimulus coding of nausea and emesis by abdominal visceral afferents and especially the vagus-how do the afferents encode information for normal postprandial sensations, nausea and finally vomiting?; Understanding the central processing of signals for nausea and vomiting is particularly problematic in the light of observations that vomiting is more readily amenable to pharmacological treatment than is nausea, despite the assumption that nausea represents "low" intensity activation of pathways that can evoke vomiting when stimulated more intensely.

Cyclic Vomiting Syndrome in 41 adults: the illness, the patients, and problems of management

BACKGROUND

Cyclic Vomiting Syndrome (CVS) is a disorder characterized by recurrent, stereotypic episodes of incapacitating nausea, vomiting and other symptoms, separated by intervals of comparative wellness. This report describes the clinical features, co-morbidities and problems encountered in management of 41 adult patients who met the diagnostic criteria for CVS.

METHODS

This is a retrospective study of adults with CVS seen between 1994 and 2003. Follow-up data were obtained by mailed questionnaires.

RESULTS

Age of onset ranged from 2 to 49 years. The duration of CVS at the time of consultation ranged from less than 1 year to 49 years. CVS episodes were stereotypic in respect of their hours of onset, symptomatology and length. Ninety-three percent of patients had recognizable prodromes. Half of the patients experienced a constellation of symptoms consisting of CVS episodes, migraine diathesis, inter-episodic dyspeptic nausea and a history of panic attacks. Deterioration in the course of CVS is indicated by coalescence of episodes in time. The prognosis of CVS is favorable in the majority of patients.

CONCLUSION

CVS is a disabling disorder affecting adults as well as children. Because its occurrence in adults is little known, patients experience delayed or mis-diagnosis and ineffectual, sometimes inappropriately invasive management.

American Gastroenterological Association technical review on the diagnosis and treatment of gastroparesis

This literature review and the recommendations herein were prepared for the American Gastroenterological Association Clinical Practice Committee. The paper was approved by the Committee on May 16, 2004, and by the AGA Governing Board on September 23, 2004.

Similarities in cyclic vomiting syndrome across age groups

OBJECTIVE

Cyclic vomiting syndrome is well recognized in children yet has poorly defined pathogenesis and treatment. Cyclic vomiting syndrome is occasionally diagnosed in older subjects, but little attempt has been made to determine if such cases represent a unique disorder.

METHODS

We reviewed clinical data from 39 patients aged 1.8-75 yr with cyclic vomiting syndrome meeting published criteria for diagnosis. Clinical characteristics were compared between subjects with symptom onset in childhood (<12 yr, n = 18) and subjects with onset at an older age (> or =12 yr, n = 21; mean age at onset 34.8+/-3.8 yr).

RESULTS

All patients had stereotypical episodes of vomiting separated by varying symptom-free intervals. The prevalence rates of prodromal symptoms, triggering events, alleviants, associated symptoms including abdominal pain and diarrhea, and past or family history of migraine were similar in the children and older subjects with the syndrome (p > 0.3 for each). Delay in diagnosis was greater in the older subset (3.1+/-0.8 yr vs 7.9+/-3.1 yr, p < 0.05). Interepisode intervals and total number of hospitalizations did not differ significantly between younger and older patients, but duration of episodes was significantly longer in the older group (2.0+/-0.5 days vs 3.8+/-0.4 days, p < 0.01). When subjects were further substratified by age of illness onset, duration of episodes progressively increased from infant/toddlers (1.8+/-0.4 days) through childhood (2.3+/-0.5 days) and adolescence (2.9+/-1.0 days) and into adulthood (3.9+/-0.5; p < 0.05 across groups). Episode duration did not lengthen further in subgroups >20 yr of age.

CONCLUSIONS

Many characteristics of cyclic vomiting syndrome are similar irrespective of age at disorder onset, suggesting a uniform pathogenesis. Duration of episodes increases with age to age 20 yr. Increased awareness of the condition and a high index of suspicion may help decrease delay in diagnosis after symptom onset.

Cyclic vomiting syndrome in adults: clinical features and response to tricyclic antidepressants

OBJECTIVE

Cyclic vomiting syndrome (CVS) has been described infrequently in adults, and treatment in both children and adults remains unsatisfactory. We report clinical features of a group of adults with CVS and anecdotal outcome from open-label treatment with tricyclic antidepressants, medications that have some efficacy in other unexplained gastrointestinal disorders.

METHODS

Clinical data were examined from 17 adult patients with CVS seen over a 10-yr period, each having been treated with a tricyclic antidepressant. Outpatient records were reviewed, clinical outcome was extracted using a priori criteria, and findings were compared with 37 patients having usual functional nausea and vomiting who also received tricyclic antidepressant therapy.

RESULTS

Symptoms in CVS began at age 35 yr (range 14-73 yr); the average episode length was 6 days (range 1-21 days) and the symptom-free interval averaged 3.1 months (range 0.5-6 months). Vomiting cycles typically began without warning, and fewer than one-third of the subjects reported a prodrome or potential trigger event, such as menstrual periods, pregnancy, or large meals. Sleep was seemingly beneficial in 23.5%. Tricyclic antidepressant therapy was associated with complete remission in 17.6% and partial response in 58.8%, but was less effective than for functional nausea and vomiting (p = 0.02).

CONCLUSIONS

CVS is a rare diagnosis with distinctive features in adults. Duration of episodes and cycles varies considerably across subjects. In open-label, uncontrolled use, tricyclic antidepressants appear beneficial for some subjects but are less effective in CVS than in chronic, persistent functional nausea and vomiting.

Precipitants and aetiology of cyclic vomiting syndrome

Thirty-two patients aged 2-22 y with cyclic vomiting syndrome (CVS), and 64 age- and gender-matched controls were assessed to determine the nature, severity, precipitants and associated features of attacks and the incidence of potential aetiological factors. The mean age of onset was 3.5 y. Patients experienced a mean of nine attacks per year, of average duration 2.4 d, and two-thirds missed more than 10 d of school per year. Patients were more likely to have migraine and co-ordination difficulties, a past history of forceps delivery and gastroesophageal reflux than controls. Compared with controls, subjects had a higher incidence of psychological symptoms (38% compared with 19%) and migraine (37% compared with 9%). CVS is a chronic, disabling condition and is a migraine variant, with attacks usually precipitated by stress and intercurrent infections.

Cyclical vomiting syndrome

Cyclical vomiting syndrome is an uncommon, disabling symptom complex of unknown cause, with features in common with migraine. It affects principally children and adolescents. Differential diagnosis and theories of pathogenesis are discussed. Therapy should be aimed at prophylaxis of vomiting bouts, 'switching off' episodes once they commence and preventing complications of established vomiting episodes. Families need rapid access to care to minimize morbidity and disruption to functioning.

Open label study of long-term effectiveness of cisapride in patients with idiopathic gastroparesis

Cisapride induces acetylcholine release in cells of the myenteric plexus, thus promoting gastrointestinal motility. We studied the effects of cisapride on 11 patients with idiopathic gastroparesis. All had negative gastrointestinal endoscopy, normal glucose, and took no drugs capable of influencing motility. Most (9/11) were prior metoclopramide treatment failures. Patients' symptoms were scored (0-60) for pain, satiety, bloating, nausea, vomiting, and heartburn. All underwent a solid gastric emptying study using a Technetium-99-labeled egg meal and received placebo prior to cisapride. There were 10 females and one male with a mean (+/- SE) age of 37.8 +/- 2.6 years. Disease duration was 7.9 +/- 2.8 years. The dose of cisapride was 30-60 mg/day and the duration of therapy was 12.6 +/- 2.6 months (range 2.5-25 months). The symptom score improved on cisapride from 30.9 +/- 3.6 to 14.4 +/- 2.7 (P < 0.002 signed rank test). Emptying half-time improved from 113 +/- 4 min to 94 +/- 6 min, and 46.9 +/- 2.4% food remaining at 120 min decreased to 35.5 +/- 3.6% (both P < 0.05). Emptying half-time in normals was 68 +/- 5 min with 16.9 +/- 2.9% remaining at 120 min. Nine of 11 patients gained weight, with a mean increase of 6.7 +/- 1.6 lb (range 2-12 lb). We conclude that cisapride significantly reduces gastrointestinal symptoms and promotes weight gain in patients with idiopathic gastroparesis and is associated with improvement in solid gastric emptying. The drug is useful in patients who previously failed metoclopramide.

Vagal system involvement in changes in small bowel motility during restraint stress: an experimental study in the dog

Changes in small intestinal motility were studied during restraint stress in fasting animals and after food; the involvement of the vagal system in the pathophysiology of these changes was assessed. Small intestinal motility was recorded in 40 dogs using electromyography with monopolar electrodes and manometry with submucosal microballoons. Twenty animals underwent bilateral truncal vagotomy. Stress increased intestinal motility (percentage of slow waves followed by action potentials in 1 min), both in fasting conditions (P < 0.001) and post-prandially (P < 0.001). It also completely abolished the migrating motor complex-interdigestive myoelectric complex periodicity characteristic of the normal fasting pattern. In dogs subjected to vagotomy, restraint stress increased motility during fasting (P < 0.001) but decreased it after feeding (P < 0.01). Restraint stress thus increases small intestinal motility, both during fasting and after food. The vagal system is partially involved in this hypermotility response.