Internal mammary artery harvesting using the harmonic scalpel.

Internal mammary artery (IMA) harvesting using the harmonic scalpel (HS) was recently introduced. We studied 541 IMAs harvested by the same surgeon through a standard median sternotomy in 472 coronary bypass patients; 252 (47%) with the HS, while 289 (53%) were with electrocautery (EC). Patient demographics included mean ages: 67 years HS vs. 65 years EC (p = NS); male:female ratio: 3:1; and insulin dependent diabetes mellitus (IDDM): 11% HS vs. 12.5% EC (NS). Mean ultrasonic IMA flow at a mean SBP of 70 mm Hg in 10 consecutive patients of each group were: preharvest, HS 11.9 +/- 2.3 ml/min vs. EC 8.5 +/- 1.6 ml/min (p = 0.256); postharvest, HS 35.7 +/- 10.7 ml/min vs. EC 22 +/- 2.9 ml/min (0.235); and postcardiopulmonary bypass (post-CPB), HS 47.8 +/- 6.2 ml/min vs. EC 41.7 +/- 2.5 ml/min (0.381). Histologic samples of 50 consecutive IMAs showed no evidence of vessel injury in either group. Clinical results revealed postoperative bleeding in 6/217 (2.7%) HS vs. 7/255 (2.7%) EC (p = 0.783), none attributed to bleeding from the IMA; phrenic paresis: 0/217 in HS but 1/255 (0.4%) in EC (p = 0.960); sternal wound infection: 5/217 (2.3%) HS vs. 6/255 (2.4%) EC (p = 0.787); postoperative IABP: 6/217 (2.7%) HS vs. 5/255 (2%) EC (p = 0.859); mortality: 2/217 (0.9%) HS vs. 2/255 (0.8%) EC (p = 0.710). Hemodynamic, histologic, and clinical results were comparable in both groups. The authors believe the HS is safe and effective for IMA harvesting.

Patient satisfaction with telemedicine in a prison environment.

Prison inmates were surveyed about their perceptions of the use of videoconferencing in clinical consultations. A 14-item questionnaire was used to assess satisfaction with the patient-physician clinical interaction. Of the 299 inmates surveyed immediately after their teleconsultations, 221 completed questionnaires that were suitable for analysis (74%). Only 9% of patients indicated that they were not satisfied with the teleconsultation. They rated the telemedicine context well above the midpoint of the scale (16) on both an information-exchange and a patient-comfort dimension, with means of 29 and 24, respectively. There was a significant difference (P < 0.01) in the patient-comfort dimension in terms of the location of the prisoners. No significant differences were found in patient satisfaction related to the specialty of the physician. The results suggest that many contextual factors must be considered to understand the communicative implications of patient satisfaction with telemedicine.

Effectiveness of telemedicine in the outpatient pulmonary clinic.

BACKGROUND: Over the past several years, there has been a resurgence of interest in telemedicine. Despite this renewed interest, some health care providers remain skeptical regarding the effectiveness of telemedicine for the delivery of health care. OBJECTIVE: The objective of this prospective, crossover study was to determine if there was any difference between care delivered using video conferencing-based telemedicine technology and that given by a traditional face-to-face encounter in a pulmonary medicine clinic. METHODS: Two pulmonologists sequentially examined 40 individuals via video conferencing-based telemedicine technology and by the traditional face-to-face method. Two additional pulmonologists, in a blinded fashion, compared the results for consistency in the history, examination with focus on auscultation of the lungs, diagnostic impression, and evaluation and treatment plans. RESULTS: Evaluation of patients by telemedicine was as effective as the traditional mode. The telemedicine physician and the physician examining the patient in the traditional manner were able to elicit the same key complaints and hear the same adventitious sounds on auscultation of the lungs. CONCLUSION: Telemedicine can enable the provision of high-quality care in a pulmonary clinic setting.

Left ventricular diastolic function after coronary artery bypass grafting: a correlative study with three different myocardial protection techniques.

BACKGROUND: This study was designed to examine the effect of myocardial protection on diastolic function after cardiac operations. METHODS: Subjects were patients with normal preoperative diastolic function who were scheduled for coronary artery bypass grafting. Group I received anterograde cardioplegia; group II received anterograde and retrograde cardioplegia; and group III was protected with ventricular fibrillation and intermittent aortic crossclamping. Operations were performed with mild hypothermia and ventricular venting through the left superior pulmonary vein in all cases. Left ventricular diastolic function was evaluated with pulsed-wave Doppler transesophageal echocardiography (samples at the mitral valve leaflet: four-chamber view) and left superior pulmonary vein flow velocity. The flow patterns were stored on videotape and sent to an independent investigator for analysis. Left ventricular ejection fraction was calculated with transesophageal echocardiography (short-axis view, two-dimensional and M-mode). RESULTS: Left ventricular diastolic function, as measured by the ratio between the peak velocities during early filling and atrial contraction and by systolic diastolic superior pulmonary venous flow ratio, was significantly impaired in all three groups 5 minutes after discontinuation of cardiopulmonary bypass. At 1 hour after operation, these values had returned to control levels only in group III. There was an increased incidence of supraventricular arrhythmias in group III. There were no significant hemodynamic differences among the three groups. CONCLUSIONS: Left ventricular diastolic function was severely impaired after cardiopulmonary bypass. The degree of impairment depended on the myocardial protection used. The impairment in diastolic function was less when ventricular fibrillation and intermittent aortic crossclamping were used, and greater when anterograde and retrograde cardioplegia were used.

An Ohio telemedicine system for prison inmates: a case report.

BACKGROUND: A project was established by The Ohio State University Medical Center (OSUMC) and the Ohio Department of Rehabilitation and Corrections (ODRC) to investigate the use of telemedicine in providing health care to Ohio's prison inmates. OBJECTIVES: To determine the effects of telemedicine on continuity of inmate care, the sense of isolation experienced by health care providers at remote institutions, the security risks incurred when transporting inmates to outside facilities, and the overall cost of care. In tracing the initial adoption and implementation of the project, the authors describe health care in Ohio's prisons and the unique nature of providing that care. METHODS: The project was conducted over a 1-year period, from November 1994 through December 1995, using a variety of methods: direct observation of inmate consultations; participation in task force meetings; unstructured interviews with physicians, prison administrators, ancillary health care personnel, and security guards; and initial collection of survey data. RESULTS: Telemedicine enables Ohio's inmates to receive health care in a more timely fashion than before. Physicians and inmates were generally satisfied, and the costs of providing inmate medical care were reduced by lessening or eliminating the need for additional security guards, vans, chase vehicles, and travel time for physicians. CONCLUSIONS: Some initial hurdles in using the system, such as scheduling and triage, are being overcome as new methods are devised, and additional incentives for specialty physicians to use the system are being investigated. The OSUMC/ODRC project suggests that the advantages of using telemedicine in prison settings are immense, and the ODRC plans to expand the network to include two more remote sites early in 1996.

The internal ventricular venting loop catheter. A new, simplified, single cannulation approach for a ventricular assist system.

The internal ventricular venting loop (IVVL) catheter is a coaxial, two lumen, bidirectional flow cannula introduced peripherally and advanced intraluminally to the pulmonary artery by its flow directed, balloon tipped inner tubing in a right ventricular assist system (RVAS), or to the left ventricle over a guide wire under fluoroscopy in a left ventricular assist system (LVAS). Its use was successfully tested in six acute canine experiments using a small IVVL catheter. Hemodynamic responses to increasing roller pump flow rates, to a maximum of 1 L/min, were initially measured. Then, hemodynamic changes to 600 ml/min, after left anterior descending artery ligation (in IVVL-LVAS) and 300 ml/min after right coronary artery ligation (in IVVL-RVAS) were regularly recorded every 15 min until cardiac arrest. The IVVL-LVAS was able to significantly decrease the pulmonary capillary wedge pressure, while the IVVL-RVAS was able to significantly decrease the central venous pressure. The IVVL system was able to partially unload the ventricles and restore about 33-60% of the cardiac output. However, it could not effectively support the heart during arrest. Thus, the IVVL catheter can facilitate simple and effective single cannulation for either RVAS or LVAS. This approach may enable ordinary cardiac centers to make use of already available blood pumps for temporary, inexpensive, and less invasive application of partially assisted circulation when intra aortic balloon pump assistance fails.

Double blind, placebo controlled trial of metronidazole in Crohn's disease.

A double blind study compared the efficacy of metronidazole in two doses (20 mg/kg, 10 mg/kg) with placebo in patients with Crohn's disease. One hundred and five patients participated but only 56 completed the 16 week study -21 were withdrawn for deterioration of symptoms, 17 for adverse experiences, and 11 for protocol violation. Significant improvement in disease activity as measured by the Crohn's disease activity index (metronidazole 20 mg/kg, 97 units; metronidazole 10 mg/kg, 67 units; placebo -1 unit, p = 0.002) and serum orosomucoid (metronidazole 20 mg/kg/day, 49; 10 mg/kg/day, 38; placebo, -9, p = 0.001)) were detected. Changes in C reactive protein concentrations did not achieve significance when all three groups were considered but were significant when all metronidazole treated patients were grouped and compared with the placebo treated patients (0.8 v -0.9, p less than 0.05). Although patients receiving metronidazole 20 mg/kg/day had a greater improvement in disease activity than those receiving 10 mg/kg/day (difference 30 units (95% confidence intervals -27-87), the small sample size may have precluded the detection of statistical significance. Preliminary analysis suggests that metronidazole was more effective in patients with disease confined to the large intestine or affecting both small and large bowel than in those with small bowel disease only. There were no differences in remission rates between metronidazole and placebo treated patients. We conclude that metronidazole warrants further assessment in the treatment of patients with active Crohn's disease.

Treatment of endocrine and nonendocrine secretory diarrheal states with Sandostatin.

Endocrine tumors of the gastroenteropancreatic (GEP) axis elaborate excessive amounts of peptides that are potent intestinal secretagogues. The actions of these peptides on intestinal transport of water and electrolytes lead to the accumulation of fluid in the intestinal lumen and diarrhea. One of the most clinically relevant secretagogues is vasoactive intestinal polypeptide (VIP). Other relevant secretagogues elaborated from tumors are serotonin, prostaglandins, and kinins. Sandostatin (octreotide, Sandoz, Basle, Switzerland), a long-acting octapeptide analog of somatostatin, inhibits experimentally induced intestinal secretion and has been used successfully to treat patients with secretory diarrhea refractory to other pharmacotherapy. The effective dose is in the range of 50 to 200 micrograms, given subcutaneously two or three times daily. The mechanism for the inhibitory effect on secretion is not clearly understood but it appears to involve inhibition of the adenylate cyclase-cyclic adenosine monophosphate system as well as interference with calcium as an intercellular mediator of enterocyte secretion. A particularly interesting use of this drug has been to treat the watery diarrhea seen in patients with acquired immunodeficiency syndrome. It is also effective in other types of secretory diarrhea not associated with endocrine tumors. These include diabetic diarrhea, idiopathic secretory diarrhea of infancy, and high output ileostomy diarrhea.

Octreotide inhibits increases in short-circuit current induced in rat colon by VIP, substance P, serotonin and aminophylline.

We investigated the effect of octreotide (OCT), a stable somatostatin analog, (OCT) on changes in short-circuit current (Isc) induced by vasoactive intestinal peptide (VIP), aminophylline, serotonin (5-HT) and substance P. OCT significantly decreased basal Isc at a concentration of 10(-9) M; the maximum decrease in Isc was observed at 10(-6) M. OCT (10(-7) M) significantly inhibited the intestinal secretory response to all the secretagogues studied. The maximum Isc response was reduced when tissues were stimulated with VIP (184.9 +/- 18.0 vs. 119.7 +/- 14.1, P less than 0.05), 5-HT (135.1 +/- 14.4 vs. 79.5 +/- 13.4, P less than 0.05) and substance P (156.0 +/- 19.2 vs. 30.7 +/- 5.4, P less than 0.01). In the case of aminophylline, the concentration-response curve was shifted to the right but the maximum response was not reduced. Because VIP and aminophylline increase cAMP while 5-HT and substance P stimulate intestinal secretion principally by a calcium linked mechanism, we conclude that OCT inhibits Isc in rat colon by more than one mechanism.

Treatment of psoriasis with chronic subcutaneous administration of somatostatin analog 201-995 (sandostatin). I. An open-label pilot study.

Increased levels of human growth hormone (HGH) may correlate with the severity of psoriasis and native somatostatin (SRIF) may improve it by inhibiting HGH release. The synthetic SRIF analog, SMS 201-995, is a potent and long-lasting HGH inhibitor. Nine patients with chronic plaque psoriasis completed 12 weeks of open treatment with SMS 201-995. Overall improvement was minimal to marked in six patients and unchanged in three; none worsened. Means of 24-hour pooled HGH (1.7 +/- 0.7 micrograms/L) and fasting plasma somatomedin-C (SM-C) (0.45 +/- 0.22 U/mL) were normal at baseline and were not significantly altered by treatment. A high frequency of gastrointestinal side effects occurred, but no patient discontinued treatment because of them. SMS 201-995 may be a useful therapy for psoriasis, but its mechanism of action is unknown. Double-blind placebo-controlled trials are currently in progress to confirm the efficacy of SMS 201-995 in psoriasis.

Medical therapy of VIPomas.

VIP-secreting tumors are rare, but they produce a dramatic clinical picture, the most prominent feature of which is profuse, watery diarrhea and hypokalemia. A definitive diagnosis is aided by the determination of plasma VIP concentrations through the use of the sensitive radioimmunoassays that are now available. Intestinal secretion resulting from the direct action of VIP on the intestinal epithelial cell receptors accounts for the loss of fluid and electrolytes in patients with VIPoma. The hypokalemia is the result of passive and VIP-induced active secretion of potassium by colonic epithelial cells. Surgery is the most definitive treatment of VIPoma; pharmacotherapy is extremely important in controlling symptoms and stabilizing the patient prior to surgery. Sandostatin and glucocorticoids are well established agents in the management of the secretory diarrhea; other pharmacologic agents, including clonidine, indomethacin, phenothiazines, lithium carbonate, and propranolol, may be helpful in selected patients but require further study. The most potent and promising drug for the treatment of VIPoma is a new peptidomimetic agent--Sandostatin. This metabolically stable synthetic analogue of somatostatin appears, in part, to inhibit the release of VIP from the tumor and the secretion of chloride by the intestine. In addition to controlling the diarrhea, it may have a direct effect on the tumor in reducing its size.

Effects of enteric neural stimulation on chloride transport in human left colon in vitro.

Nonpathological segments of muscle-stripped left colon from patients undergoing surgery for carcinoma, diverticulitis, or other causes were set up in flux chambers in order to determine the influence of intrinsic neurons on ion transport. In the basal state, both sodium and chloride were actively absorbed, and there was no significant residual ion flux. Electrical field stimulation of the intrinsic mucosal innervation evoked an increase in short-circuit current that was dependent on stimulus frequency and strength. The response was mimicked by scorpion venom, which is known to depolarize neurons, and was nearly abolished by tetrodotoxin, which prevents neurotransmitter release. Atropine reduced, but did not abolish, the response to neural stimulation. Carbachol, aminophylline, and theophylline significantly increased short-circuit current above basal levels. Electrical field stimulation evoked an increase in short-circuit current that could be accounted for by a decrease in net chloride absorption without any significant effect on sodium absorption or residual ion flux. These results suggest that ion transport in the human left colon is regulated by intrinsic submucosal cholinergic neurons as well as other neuronal types, and activation of these nerves could provide the basis for certain diarrheal disorders.

Effect of somatostatin analogue (SMS 201-995) on molecular species of gastrin in gastrinoma.

Somatostatin analogue (SMS 201-995) has been shown to decrease total serum gastrin in patients with gastrinoma; however, the gastrin level rarely returns to normal, despite the near-complete inhibition of acid secretion. This implies that SMS may have an inhibitory action on the biologically active molecular species of gastrin and have little effect on biologically inactive species. To test this hypothesis, we determined the effect of SMS on the molecular species of gastrin in eight patients with the Zollinger-Ellison syndrome. Serum obtained before treatment and 6 hours and 18 hours after treatment (SMS 1 microgram/kg, subcutaneously) was sampled and assayed for molecular species of gastrin by means of gel filtration chromatography and fractional quantitation of gastrin species by radioimmunoassay. There was a significant decrease in the amount of G-34 and G-17 species. BBG and G-14 decreased, a change not significant at 6 hours but significant 18 hours after SMS. The distribution of the various molecular species as a percent of total immunoreactive gastrin was analyzed before and after SMS. There was a shift in the distribution of the molecular species, so that 6 hours after SMS treatment nearly 50% of total gastrin activity was accounted for by BBG and component I. SMS seems to have a different potency to inhibit release of the various gastrin molecular species. This observation may explain the failure of total gastrin levels to return to normal after SMS treatment in patients with the Zollinger-Ellison syndrome.