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Guy Voeller

Publications and source records attributed to Guy Voeller.

6 recordsLinked to original sources
PubMed2005

Driving gastric electrical activity with electrical stimulation.

Gastric electrical stimulation (GES) therapy is generating a lot of interest, but it is still investigational. Its efficacy in driving gastric electrical activity and improving motility, and the ideal frequency for bringing this about are still controversial. In this study, a rule-based computer model of tissue electrical response to stimulation was developed to examine the interaction between tissue electrical refractoriness and the onset of tissue activation. The results were compared to response to GES in 8 dogs implanted with electrodes and strain gauges and stimulated at frequencies ranging from 3 to 30 cycles/min. Simulated electrical control activity at an intrinsic frequency of 5/min was entrained from 2.0 cycles/min to 7.92 cycles/min. The regularity of the ECA elicited by stimulation depended on the number of pulses injected. Electrical stimulation in canine stomach entrained the native electrical control activity from a baseline average of 5.14 +/- 0.32 cycles/min up to 9.2 cycles/min. Contractile response to stimulation at 20-30 cycles/min were significantly higher (p < 0.05). Computer simulation of GES may be a useful tool to complement and reduce some of the costs associated with empirical studies of gastric electrical stimulation in establishing its possible use in treating drug refractory gastroparesis.

Animals↗
PubMed2005

Pilot study on gastric electrical stimulation on surgery-associated gastroparesis: long-term outcome.

OBJECTIVES: Patients with postgastric surgery gastroparesis are often unresponsive to conventional medical therapy. Gastric electrical stimulation (GES) with the use of high-frequency and low-energy neural stimulation is an approved technique for patients with idiopathic and diabetic gastroparesis. METHODS: We hypothesized that GES would improve symptoms, health resource utilization, and gastric emptying in six patients with postsurgical gastroparesis from a variety of surgical procedures. Patients were evaluated by means of the following criteria: symptoms, health-related quality of life, and gastric emptying tests at baseline over time. RESULTS: All patients noted improvements after device implantation for up to 46 months: the frequency score for weekly vomiting went from a baseline of 3.2 down to 0.4 immediately after treatment before settling at 1.4 by the long-term follow up. Total gastrointestinal symptom score went from 36.5 at baseline down to 12.3 before settling at 20.5 at long-term follow up. Improvements were also seen in health-related quality of life and solid and liquid gastric emptying. CONCLUSIONS: We conclude that GES is associated with clinical improvements in this group of patients with either postsurgical or surgery-associated gastroparesis. This pilot study with long-term outcomes offers evidence for a new therapy for otherwise refractory patients with gastroparesis associated with previous surgery.

Adult↗
PubMed2003

Laparoscopic repair of ventral hernias: nine years' experience with 850 consecutive hernias.

OBJECTIVE: To evaluate the efficacy and safety of laparoscopic repair of ventral hernias. SUMMARY BACKGROUND DATA: The recurrence rate after standard repair of ventral hernias may be as high as 12-52%, and the wide surgical dissection required often results in wound complications. Use of a laparoscopic approach may decrease rates of complications and recurrence after ventral hernia repair. METHODS: Data on all patients who underwent laparoscopic ventral hernia repair (LVHR) performed by 4 surgeons using a standardized procedure between November 1993 and October 2002 were collected prospectively (85% of patients) or retrospectively. RESULTS: LVHR was completed in 819 of the 850 patients (422 men; 428 women) in whom it was attempted. Thirty-four percent of completed LVHRs were for recurrent hernias. The patient mean body mass index was 32; the mean defect size was 118 cm2. Mesh, averaging 344 cm2, was used in all cases. Mean operating time was 120 min, mean estimated blood loss was 49 mL, and hospital stay averaged 2.3 days. There were 128 complications in 112 patients (13.2%). One patient died of a myocardial infarction. The most common complications were ileus (3%) and prolonged seroma (2.6%). During a mean follow-up time of 20.2 months (range, 1-94 months), the hernia recurrence rate was 4.7%. Recurrence was associated with large defects, obesity, previous open repairs, and perioperative complications. CONCLUSION: In this large series, LVHR had a low rate of conversion to open surgery, a short hospital stay, a moderate complication rate, and a low risk of recurrence.

Body Mass Index↗
PubMedDate not supplied

Minimal adhesions to ePTFE mesh after laparoscopic ventral incisional hernia repair: reoperative findings in 65 cases.

OBJECTIVES: Laparoscopic ventral incisional hernia repair involves intraabdominal placement of a synthetic mesh, and the possibility of formation of severe visceral adhesions to the prosthesis is a principal concern. Little clinical information based on reoperative findings is available about adhesions to biomaterials placed intraabdominally. We conducted a multiinstitutional study of adhesions to implanted expanded polytetrafluoroethylene (ePTFE) mesh at reoperation in patients who had previously undergone laparoscopic incisional hernia repair done with the same mesh implantation technique. METHODS: Nine surgeons retrospectively assessed the severity of adhesions to ePTFE mesh at reoperation in 65 patients. For each case, adhesions were assigned a score of 0 to 3, with 0 indicating no adhesions and 3 severe adhesions. RESULTS: The mean time from mesh implantation to reoperation was 420 days (range, 2 to 1739 days). No adhesions were observed in 15 cases. Forty-four cases received an adhesion score of 1, and 6 cases a score of 2; no scores of 3 were assigned. Thus, 59 patients (91%) had either no or filmy, avascular adhesions. No enterotomies occurred during adhesiolysis. CONCLUSIONS: In this large series of reoperations after laparoscopic incisional hernia repair, no or minimal formation of adhesions to implanted ePTFE mesh was observed in 91% of cases, and no severe cohesive adhesions were found. Comparative analyses of newer materials based on clinical reoperative findings are warranted to assess the safety of intraabdominally placed meshes.

Adult↗
PubMedDate not supplied

Laparoscopy shortens length of stay in patients with gastric electrical stimulators.

BACKGROUND: Gastric electrical stimulation has been proven effective for drug-refractory gastroparesis. Placement of stimulator leads and device usually requires a laparotomy, although laparoscopic placement has also been used. METHODS: To compare laparotomy with laparoscopy, we examined 36 patients, 18 undergoing laparoscopy and 18 undergoing laparotomy, matched for primary diagnosis and health resource usage. We compared baseline symptoms, length of surgery, length of postoperative hospital stay, gastric emptying, and health resources in each of the 2 groups over time, to see what variables, if any, differed. RESULTS: Baseline symptoms, gastric emptying, and health resource usage were similar. Operative times were also similar, but length of stay declined from a mean of 6.4 days for laparotomy to 1.1 days for laparoscopy. Long-term outcome, via symptoms, gastric emptying, and health resource utilization were comparable between the 2 groups. CONCLUSION: Laparoscopic placement of gastric electrical stimulator leads and device is associated with shorter lengths of postoperative hospital stay. However, the patients who underwent laparotomy had higher vomiting scores and more previous abdominal surgeries at baseline, and higher long-term mortality at follow-up, suggesting that they may be more ill, as a group, than the laparoscopic patients. Laparoscopic placement of devices may be preferable when technically feasible.

Adult↗