Magnetic detection to position human nasogastric tubes.

Placement of nasogastric tubes is one of the most commonly performed diagnostic and therapeutic medical procedures. Proper placement of the tube in the digestive tract below the diaphragm is crucial for efficacy and safety. This study evaluates a magnet detection system that allows percutaneous non-radiographic localization of the nasogastric tube tip. Each volunteer subject had the magnet detector placed over the abdomen, and was then intubated with a magnet-tagged nasogastric tube. Eighty-eight nasogastric tube placements were performed in 22 volunteers. The detection system located the nasogastric tube tip below the diaphragm in all 88 placements. Location in all attempts was confirmed by fluoroscopy. This method of correctly locating the tip of nasogastric tubes may obviate the need for radiographic imaging in most cases.

Magnetic field goniometry: a new method to measure the frequency of stomach contractions.

A system of magnetic field goniometry was developed for measuring the frequency of stomach contractions. This technique uses a handheld, electronic compass to measure the angular change in direction of a magnetic field generated by a small, ingested magnet. Measurements of gastric mechanical activity made by goniometry were validated with simultaneous measurements using manometry and electrogastrography. The agreement between these different modalities was excellent. In this pilot study, magnetic field goniometry provided an easy, minimally invasive, and accurate method to measure the frequency of gastric contractions.

Esophageal rings, webs, and diverticula.

Rings, webs, and diverticula are among the most common anatomic anomalies of the esophagus. Although these structural lesions are often asymptomatic, patients can develop significant problems with dysphagia, regurgitation, and aspiration. This article discusses the epidemiology, pathogenesis, diagnosis, and therapy of esophageal rings, webs, and diverticula with emphasis on the clinical, diagnostic, and therapeutic strategies involved in caring for patients with these conditions.

Increased prevalence of gastroesophageal reflux in patients with idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal interstitial lung disease (ILD) of unknown etiology. Introduction of acid into the respiratory tree can produce pulmonary fibrosis. Gastroesophageal reflux (GER) has previously been associated with several other respiratory conditions, including pneumonia, bronchitis, and asthma. To investigate prospectively the possible association of GER and IPF, 17 consecutive patients with biopsy-proven IPF and eight control patients with ILD other than IPF underwent dual-channel, ambulatory esophageal pH monitoring. Sixteen of 17 patients with IPF had abnormal distal and/or proximal esophageal acid exposure compared with four of eight control patients (p = 0.02). In the patients with IPF, mean percent distal total (13.6 versus 3.34, p = 0.006), distal upright (12.4 versus 5.1, p = 0.04), distal supine (14.7 versus 0.88, p = 0.02), and proximal supine (7.48 versus 0.24, p = 0.04) esophageal acid exposure times were significantly greater than those in control patients. Only four patients with IPF (25%) with increased acid exposure had typical reflux symptoms such as heartburn or regurgitation. Patients with IPF have a high prevalence of increased esophageal acid exposure, usually without typical GER symptoms. GER in these patients tends to occur at night and extend into the proximal esophagus. Acid reflux may be a contributing factor in the pathogenesis of IPF.

Bleeding from gastric antral vascular ectasia in marrow transplant patients.

BACKGROUND: Gastric antral vascular ectasia (GAVE) leads to blood loss in the disorders of "watermelon stomach" and portal gastropathy, but is not a commonly recognized complication of marrow transplantation. METHODS: GAVE was diagnosed when capillary ectasia, focal capillary thromboses, and fibromuscular hyperplasia were identified in antral mucosal biopsy specimens. Marrow transplant patients bleeding from GAVE were reviewed to ascertain common variables in their pretransplant, posttransplant, and bleeding course. RESULTS: Six patients developed bleeding due to GAVE. The onset of bleeding was 18 to 94 days after transplant and required an average of 37 U of blood (range, 2 to 130 U). Two patients stopped bleeding after restoration of platelet counts. Two patients had surgical antral resections; both died of multiorgan failure after surgery. Two patients had successful endoscopic laser ablation of vascular lesions and survived. Factors possibly associated with GAVE included male gender, VOD of the liver, oral busulfan as part of the conditioning regimen, and growth factor use after transplant. CONCLUSIONS: GAVE was a cause of gastric bleeding in six patients with marrow transplant patients. Restoration of platelet counts and endoscopic laser photocoagulation are the therapies of choice for ongoing bleeding in these patients.