Benefit of intravenous antispasmodic (hyoscyamine sulfate) as premedication for colonoscopy.

BACKGROUND: We sought to determine whether premedication for colonoscopy with intravenous hyoscyamine sulfate (Levsin) was helpful from the standpoint of the colonoscopist and the patient. METHODS: One hundred sixteen adult patients were randomized to receive either 0.5 mg hyoscyamine sulfate intravenous (n = 57) or placebo (n = 59). After administration of study drug, patients were given meperidine and midazolam. Parameters measured included the time required to reach the cecum, total procedure time, and the endoscopist's perception of the adequacy of sedation, difficulty of insertion, and amount of colonic spasm on insertion and withdrawal. Patients were given a postprocedure questionnaire assessing their experience. RESULTS: In patients receiving hyoscyamine, there was a shorter cecal intubation time (median 9.2 vs. 12.9 minutes; p = 0. 01), shorter total colonoscopy time (median 20.5 vs. 25.0 minutes; p = 0.01), better patient sedation (p = 0.02), easier colonic insertion (p = 0.001), and less spasm on insertion (p = 0.01). No difference was found in the amount of spasm during withdrawal or the total dosages of meperidine or midazolam used. Patients receiving hyoscyamine sulfate reported being more comfortable during their procedures ( p < 0.001) and were more willing to repeat colonoscopy in the future (p = 0.0001). The only adverse effect seen during the study was a 27% incidence of sinus tachycardia that occurred in patients receiving hyoscyamine. CONCLUSIONS: Premedication with intravenous hyoscyamine sulfate was beneficial in terms of the time required for cecal intubation, total procedure time, adequacy of sedation, and scales of patient comfort. However, the high frequency of sinus tachycardia seen with the dose used in our study, which was extremely rapid in two patients, indicates the need for further study before the drug can be recommended as a routine premedication for colonoscopy.

Prevalence of open-access gastrointestinal endoscopy in the United States.

OBJECTIVE: Open-access endoscopy allows physicians who are not gastroenterologists to directly schedule patients for endoscopic procedures without having them first seen in the gastrointestinal clinic. We sought to determine the prevalence of open-access endoscopy in the United States and to examine endoscopists' attitudes toward the practice. METHODS: Questionnaires were mailed to a random sample of 1500 members of the American Society for Gastrointestinal Endoscopy. Out of 1460 that apparently reached the endoscopist, 577 (39.5%) were returned and analyzed. RESULTS: Of the endoscopists who responded, 60.5% said that they offered some form of open-access endoscopy. Open-access endoscopy comprised less than 10% of outpatient endoscopic practice for 48.2% of individuals who reported they offered the service; it comprised over 25% of practice in 19.8%. Of those doing it, the procedures offered on an open-access basis included esophagogastroduodenoscopy 86.0%, colonoscopy 76.5%, flexible sigmoidoscopy 94.3%, ERCP 7.7%, and endoscopic ultrasonography 4.3%. For endoscopists not offering open-access endoscopy, the most important reasons were concern about performing "not indicated" procedures (85.1 %), medical-legal issues (65.8%), and failure to believe in the concept of open-access endoscopy (59.6%). Attitudes toward open access endoscopy were significantly different among endoscopists who did and did not practice it. CONCLUSIONS: Open-access endoscopy, offered by more than 60% of the American endoscopists who responded to our survey, has become an important method of health care delivery in this country.

Predictors of patient cooperation during gastrointestinal endoscopy.

We examined a number of patient variables, including three different scales of preprocedure patient anxiety, to determine which best predicted patient cooperation and satisfaction with gastrointestinal endoscopy. We prospectively evaluated 251 patients undergoing outpatient diagnostic esophagogastroduodenoscopy and colonoscopy under conscious sedation. All were given a questionnaire on arrival to our endoscopy center that included three measures of preprocedure anxiety: (a) a single question asking how anxious the patient was (termed "Anxiety I" scale); (b) a visual linear analog scale of anxiety; and (c) the Hospital Anxiety and Depression scale. Patient cooperation during the procedure was rated by the attending endoscopist. Patients were telephoned the next day to complete a questionnaire assessing their endoscopic experience. Logistic regression analysis was used to construct models for predicting which patients were most likely to have difficulty during their procedures from both the endoscopists' and the patients' standpoint. Statistical analysis identified three parameters that by themselves significantly correlated with patient cooperation during endoscopy: age (p = 0.008), Anxiety I scale (p = 0.03), and visual linear analog anxiety score (p = 0.02). When used together, age, type of procedure, and Anxiety I scale were the best predictors of patient cooperation from the standpoint of the endoscopist. Age, type of procedure, Anxiety I scale, and education level were the best predictors of satisfaction with endoscopy from the perspective of the patient. Good cooperation during endoscopy was associated with greater patient satisfaction.

Are patients who undergo open-access endoscopy more anxious about their procedures than patients referred from the GI clinic?

OBJECTIVES: Our academic hospital center operates an open access endoscopy service that allows referring physicians to directly schedule patients for outpatient esophagogastroduodenoscopy and colonoscopy without having them first seen in the GI clinic. Although patients from the GI clinic have an opportunity to meet the endoscopist and discuss their procedures directly beforehand, patients who are scheduled to undergo endoscopy through our open access service receive only a brief telephone call from a GI fellow or nurse that is made to screen for contraindications to the procedure and to give instructions. Our objective was to find out whether patients who used our open access service were more anxious about their procedures than those referred from the GI clinic. METHODS: On arrival to our endoscopy center, consecutive patients from the open access service (n = 142) and the GI clinic (n = 85) completed a questionnaire that included three measures of anxiety. After completion of the endoscopic procedure, the attending endoscopist rated patient cooperation. Patients also completed a phone questionnaire on the day after their procedures assessing their experience with endoscopy. RESULTS: We found no difference between patients from the open access service and those from the GI clinic in any of the measures of preprocedure anxiety, in scores measuring cooperation during procedures, or in patient ratings of their experience with endoscopy as assessed on the day after procedures. CONCLUSIONS: Patients who used our open access service were no more anxious about their procedures or less cooperative during them than patients first seen in the GI clinic. In both groups, procedure-related anxiety was decreased in patients who had previously undergone endoscopy.

Appropriateness of referrals for open-access endoscopy. How do physicians in different medical specialties do?

BACKGROUND: Open-access endoscopy allows nongastroenterologist physicians the opportunity to directly schedule elective common endoscopic procedures for their patients without having them first examined in the gastrointestinal clinic. There are few data as to whether nongastroenterologist physicians in the United States schedule patients for appropriate indications. OBJECTIVES: To examine our practice to see whether patients undergoing open-access endoscopy were scheduled for appropriate indications and to see whether there were differences among physicians in various medical specialties. METHODS: We prospectively tracked 310 consecutive patients scheduled for open-access esophagogastroduodenoscopy (EGD) and colonoscopy by nongastroenterologist physicians over a 9-month period in our academic practice setting to determine whether the indications for performing the procedures were appropriate. The American Society for Gastrointestinal Endoscopy criteria (revised in 1992) were used as the standard for comparison. RESULTS: Primary care physicians (family practitioners and general internists) did a superior job of scheduling patients for appropriate indications for EGD and colonoscopy than did non-primary care physicians (internal medicine subspecialists and surgeons): 97.0% vs 81.3% for EGD (P = .04) and 84.9% vs 66.7% for colonoscopy (P = .02), respectively., CONCLUSIONS: Primary care physicians were significantly more likely to schedule patients for open-access EGD and colonoscopy for appropriate indications than were non-primary care physicians. The frequency of inappropriate indications for colonoscopy referrals was greater than for EGD. The reasons for the differences among primary care physicians, surgeons, and internal medicine subspecialists require further exploration.

Severe dysphagia, dysmotility, and unusual saccular dilation (diverticulum) of the esophagus following excision of an asymptomatic congenital cyst.

Iatrogenic dysmotility syndromes, particularly achalasia-like conditions, occasionally complicate esophageal and paraesophageal surgery. We describe a patient who developed a very unusual (and as far as we know unreported) syndrome characterized by severe dysphagia, esophageal dysmotility (segmental simultaneous contractions of the distal esophagus), and very large saccular outpouching (diverticulum) involving the right wall of the distal half of the esophagus as a consequence of excision of an asymptomatic congenital cyst. The cyst had been discovered as an incidental finding on a preemployment chest x-ray. Our patient's dysphagia did not improve with nonsurgical treatments that are usually successful for idiopathic and iatrogenic achalasia.

Chloride transport in human proximal colonic apical membrane vesicles.

The mechanism(s) of Cl- transport across the human colonic apical membranes are not well understood. Apical membrane vesicles (AMV) purified from organ donor proximal colonic mucosa and a rapid millipore filtration technique were utilized to study 36Cl- uptake into these vesicles. Outwardly directed OH- and HCO3- gradient stimulated 36Cl- uptake into these vesicles demonstrating a transient accumulation over equilibrium uptake. Voltage clamping the membrane potential of the vesicles or making them inside positive with K+/valinomycin failed to influence chloride uptake, indicating that the conductive Cl- uptake pathway is minimal in proximal colonic AMV. Anion exchange inhibitors, DIDS and SITS (1 mM) inhibited OH- and HCO3- stimulated 36Cl- uptake by approximately 60%. Furosemide also demonstrated a small but significant inhibition of chloride uptake. Amiloride, bumetanide and acetazolamide (1 mM) failed to inhibit 36Cl uptake. HCO3- and pH gradient stimulated 36Cl- uptake exhibited saturation kinetics with an apparent Km for chloride of 4.0 +/- 0.7 mM and Vmax of 17.8 +/- 3.9 nmol/mg per min. Bromide, chloride, nitrate and acetate (50 mM each) inhibited 5 mM 36Cl uptake. Inwardly directed gradients of Na+, K+, or Na+ and K+ did not stimulate 36Cl- uptake into these vesicles, indicating that uptake of Na+ and Cl- in human proximal colonic AMV does not involve Na-Cl or Na-K-2Cl cotransport. The above findings indicate that chloride transport in human proximal colonic AMV involves an electroneutral Cl-HCO3- (OH-) exchange process. In view of the previous demonstration of Na+-H+ antiporter in these vesicles, dual ion exchange mechanism of Na+-H+ and Cl-HCO3- in apical membrane domain of human colonocytes is postulated to be the primary mechanism for NaCl absorption in the human proximal colon.