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Dive into the research topics where Kenneth W. Sharp is active.

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Featured researches published by Kenneth W. Sharp.


Annals of Surgery | 2004

Heller myotomy versus Heller myotomy with Dor fundoplication for achalasia: a prospective randomized double-blind clinical trial.

William O. Richards; Alfonso Torquati; Michael D. Holzman; Leena Khaitan; Daniel W. Byrne; Rami Lutfi; Kenneth W. Sharp

Objective:We sought to determine the impact of the addition of Dor fundoplication on the incidence of postoperative gastroesophageal reflux (GER) after Heller myotomy. Summary Background Data:Based only on case series, many surgeons believe that an antireflux procedure should be added to the Heller myotomy. However, no prospective randomized data support this approach. Patients and Methods:In this prospective, randomized, double-blind, institutional review board-approved clinical trial, patients with achalasia were assigned to undergo Heller myotomy or Heller myotomy plus Dor fundoplication. Patients were studied via 24-hour pH study and manometry at 6 months postoperatively. Pathologic GER was defined as distal esophageal time acid exposure time greater than 4.2% per 24-hour period. The outcome variables were analyzed on an intention-to-treat basis. Results:Forty-three patients were enrolled. There were no differences in the baseline characteristics between study groups. Pathologic GER occurred in 10 of 21 patients (47.6%) after Heller and in 2 of 22 patients (9.1%) after Heller plus Dor (P = 0.005). Heller plus Dor was associated with a significant reduction in the risk of GER (relative risk 0.11; 95% confidence interval 0.02–0.59; P = 0.01). Median distal esophageal acid exposure time was lower in the Heller plus Dor (0.4%; range, 0–16.7) compared with the Heller group (4.9%; range, 0.1–43.6; P = 0.001). No significant difference in surgical outcome between the 2 techniques with respect to postoperative lower-esophageal sphincter pressure or postoperative dysphagia score was observed. Conclusions:Heller Myotomy plus Dor Fundoplication was superior to Heller myotomy alone in regard to the incidence of postoperative GER.


Annals of Surgery | 1993

The staged celiotomy for trauma. Issues in unpacking and reconstruction.

John A. Morris; Virginia A. Eddy; Thane A. Blinman; Edmund J. Rutherford; Kenneth W. Sharp

OBJECTIVE This article describes the important clinical events and decisions surrounding the reconstruction/unpacking portion of the staged celiotomy for trauma. METHODS Of 13,817 consecutive trauma admissions, 1175 received trauma celiotomies. Of these, 107 patients (9.1%) underwent staged celiotomy with abdominal packing. The authors examined medical records to identify and characterize: (1) indications and timing of reconstruction, (2) criteria for emergency return to the operating room, (3) complications after reconstruction, and (4) abdominal compartment syndrome (ACS). RESULTS Fifty-eight patients (54.2%) survived to reconstruction, 43 (74.1%) survived to discharge; 9 patients (15.5%) were returned to the operating room for bleeding; 13 patients required multiple packing procedures. There were 117 complications; 8 patients had positive blood cultures, abdominal abscesses developed in 6 patients, and ACS developed in 16 patients. CONCLUSIONS 1. Reconstruction should occur after temperature, coagulopathy, and acidosis are corrected, usually within 36 hours after the damage control procedure. 2. Emergent reoperation should occur in any normothermic patient with unabated bleeding (greater than 2 U packed cells/hr). 3. ACS occurs in 15% of patients and is characterized by high peak inspiratory pressure, CO2 retention, and oliguria. Lethal reperfusion syndrome is common but preventable.


Annals of Surgery | 1992

Abdominal packing for surgically uncontrollable hemorrhage.

Kenneth W. Sharp; Richard J. Locicero

Planned intra-abdominal packing for surgically uncontrollable hemorrhage from liver and retroperitoneal injuries exacerbated by hypothermia, acidosis, and coagulopathy regained popularity over the past decade. The authors reviewed 39 patients injured between August 1985 and September 1990; 31 packed for liver injuries, eight for nonliver injuries. The overall mortality rate was 44% (17/39); 9 (23%) exsanguinated, 3 (8%) died of head injuries, 3 (8%) of multisystem organ failure, 2 (5%) of late complications. The mean age was 33.9 +/- 16.2 (range, 16 to 79); there were 26 men and 13 women. Relaparotomy for pack removal was performed 2.0 +/- 1.1 days (range, 1 to 7) after initial operation. The authors identified intraoperative risk factors of pH less than or equal to 7.18, temperature less than or equal to 33 C, prothrombin time greater than or equal to 16, partial thromboplastin time greater than or equal to 50, and transfusion of 10 units or more of blood as highly predictive of outcome. Patients with four to five risk factors (n = 3) had a 100% mortality rate (p less than 0.04); two to three risk factors (n = 12), 83% mortality rate (p less than 0.003), compared with zero to one risk factors (n = 24), 18% mortality rate. Complications developed in six of 22 survivors (27%): 5 abdominal abscesses (23%), 2 wound dehiscences (9%), and 2 enterocutaneous fistulae (9%). Intra-abdominal packing will not stop all bleeding; 23% of the patients exsanguinated. In 77%, packing helped achieve hemostasis we believed was not otherwise possible. Packing may be done to prevent the development of acidosis, hypothermia, and coagulopathy or may be done early in the treatment of cold, acidotic patients rather than massive transfusion in the face of surgically uncorrectable bleeding.


Annals of Surgery | 2002

100 Consecutive Minimally Invasive Heller Myotomies: Lessons Learned

Kenneth W. Sharp; Leena Khaitan; Stefan Scholz; Michael D. Holzman; William O. Richards

ObjectiveTo evaluate the authors’ first 100 patients treated for achalasia by a minimally invasive approach. MethodsBetween November 1992 and February 2001, the authors performed 95 laparoscopic and 5 thoracoscopic Heller myotomies in 100 patients (age 49.5 ± 1.5 years) with manometrically confirmed achalasia. Before presentation, 51 patients had previous dilation, 23 had been treated with botulinum toxin (Botox), and 4 had undergone prior myotomy. Laparoscopic myotomy was performed by incising the distal 4 to 6 cm of esophageal musculature and extended 1 to 2 cm onto the cardia under endoscopic guidance. Fifteen patients underwent antireflux procedures. ResultsThere were eight intraoperative perforations and only four conversions to open surgery. Follow-up is 10.8 ± 1 months; 75% of the patients have been followed up for at least 14 months. Outcomes assessed by patient questionnaires revealed satisfactory relief of dysphagia in 93 patients and “poor” relief in 7 patients. Postoperative heartburn symptoms were reported as “moderate to severe” in 14 patients and “none or mild” in 86 patients. Fourteen patients required postoperative procedures for continued symptoms of dysphagia after myotomy. Esophageal manometry studies revealed a decrease in lower esophageal sphincter pressure (LESP) from 37 ± 1 mm Hg to 14 ± 1 mm Hg. Patients with a decrease in LESP of more than 18 mm Hg and whose absolute postoperative LESP was 18 or less were more likely to have relief of dysphagia after surgery. Thirty-one patients who underwent Heller alone were studied with a 24-hour esophageal pH probe and had a median Johnson-DeMeester score of 10 (normal <22.0). Mean esophageal acid exposure time was 3 ± 0.6% (normal 4.2%). Symptoms did not correlate with esophageal acid exposure. ConclusionsThe results after minimally invasive treatment for achalasia are equivalent to historical outcomes with open techniques. Satisfactory outcomes occurred in 93% of patients. Patients whose postoperative LESP was less than 18 mm Hg reported the fewest symptoms. After myotomy, patients rarely have abnormal esophageal acid exposure, and the addition of an antireflux procedure is not required.


Journal of Pediatric Surgery | 1991

Laparoscopic cholecystectomy in the pediatric patient

George W. Holcomb; Douglas O. Olsen; Kenneth W. Sharp

Since June 1990, five girls and one boy have been evaluated for biliary colic. Gallstones were documented by sonography. Two girls, ages 8 and 14 years, had hereditary spherocytosis, and a 9-year-old boy had sickle cell disease. The other three girls, ages 13, 13, and 15 years, developed cholelithiasis and biliary colic without a history of hematological disease. Three children weighed less than 90 lb, with the smallest weighing 45 lb. All patients underwent laparoscopic cholecystectomy without complications. Operative cholangiography was performed in five of the six children. The KTP-532 laser was used for dissection of the gallbladder from the liver bed in two patients, and electrocautery was used in the remaining four. The average operating time was 1 hour 45 minutes. This is a report of the use of laparoscopic cholecystectomy in pediatric patients. The advantages of its use include a shorter hospitalization, decreased postoperative discomfort, and a much shorter interval between the surgical procedure and return to normal activities such as school and play. At this time, it is recommended for those children without complications from their cholelithiasis such as common duct obstruction and gallstone pancreatitis.


Annals of Surgery | 2006

Laparoscopic Myotomy for Achalasia: Predictors of Successful Outcome After 200 Cases

Alfonso Torquati; William O. Richards; Michael D. Holzman; Kenneth W. Sharp

Objective:Laparoscopic myotomy is the preferred treatment of achalasia. Our objectives were to assess the long-term outcome of esophageal myotomy and to identify preoperative factors influencing the outcome. Methods:Preoperative and long-term outcome data were collected from patients undergoing laparoscopic myotomy for achalasia at our institution. The primary endpoint of the study was the postoperative change (delta) in dysphagia score. This score was calculated by combining the frequency and the severity of dysphagia. Persistent postoperative dysphagia was defined as 1 standard deviation less than the mean delta score of all patients. Logistic regression was used to identify independent preoperative factors associated with successful myotomy. Results:A total of 200 consecutive patients were included in the study. At a mean follow-up of 42.1 months, the mean delta dysphagia score was 7.1 ± 2.6; therefore, the myotomy was considered successful when the delta score was >4.5. According to this definition, 170 (85%) patients achieved excellent dysphagia relief (responders). Responders had higher preoperative low esophageal sphincter (LES) pressure than nonresponders: 42.6 ± 13.1 versus 23.8 ± 7.0 mm Hg (P = 0.001). High preoperative LES pressure remained an independent predictor of excellent response in the multivariate logistic regression model. Patients with LES pressure >35 mm Hg had an odds ratio of 21.3, making more likely to achieve excellent dysphagia relief after myotomy compared with those with LES pressure ≤35 mm Hg (odds ratio, 21.3; 95% confidence interval, 6.1–73.5, P = 0.0001). Conclusion:Laparoscopic myotomy can durably relieve symptoms of dysphagia. Elevated preoperative LES pressure represents the strongest positive outcome predictor.


Annals of Surgery | 2003

Paradigm Shift in the Management of Gastroesophageal Reflux Disease

William O. Richards; Hugh L. Houston; Alfonso Torquati; Leena Khaitan; Michael D. Holzman; Kenneth W. Sharp

ObjectiveTo compare the short-term results of the radiofrequency treatment of the gastroesophageal junction known as the Stretta procedure versus laparoscopic fundoplication (LF) in patients with gastroesophageal reflux disease (GERD). Summary Background DataThe Stretta procedure has been shown to be safe, well tolerated, and highly effective in the treatment of GERD. MethodsAll patients presenting to Vanderbilt University Medical Center for surgical evaluation of GERD between August 2000 and March 2002 were prospectively evaluated under an IRB-approved protocol. All patients underwent esophageal motility testing and endoscopy that documented GERD preoperatively, either by a positive 24-hour pH study or biopsy-proven esophagitis. Patients were offered the Stretta procedure if they had documented GERD and did not have a hiatal hernia larger than 2 cm, LES pressure less than 8 mmHg, or Barrett’s esophagus. Patients with larger hiatal hernias, LES pressure less than 8 mmHg, or Barrett’s were offered LF. All patients were studied pre- and postoperatively with validated GERD-specific quality-of-life questionnaires (QOLRAD) and short-form health surveys (SF-12). Current medication use and satisfaction with the procedure was also obtained. ResultsResults are reported as mean ± SEM. Seventy-five patients (age 49 ± 14 years, 44% male, 56% female) underwent LF and 65 patients (age 46 ± 12 years, 42%, 58% female) underwent the Stretta procedure. Preoperative esophageal acid exposure time was higher in the LF group. Preoperative LES pressure was higher in the Stretta group. In the LF group, 41% had large hiatal hernias (>2 cm), 8 patients required Collis gastroplasty, 6 had Barrett’s esophagus, and 10 had undergone previous fundoplication. At 6 months, the QOLRAD and SF-12 scores were significantly improved within both groups. There was an equal magnitude of improvement between pre- and postoperative QOLRAD and SF-12 scores between Stretta and LF patients. Fifty-eight percent of Stretta patients were off proton pump inhibitors, and an additional 31% had reduced their dose significantly; 97% of LF patients were off PPIs. Twenty-two Stretta patients returned for 24-hour pH testing at a mean of 7.2 ± 0.5 months, and there was a significant reduction in esophageal acid exposure time. Both groups were highly satisfied with their procedure. ConclusionsThe addition of a less invasive, endoscopic treatment for GERD to the surgical algorithm has allowed the authors to stratify the management of GERD patients to treatment with either Stretta or LF according to size of hiatal hernia, LES pressure, Barrett’s esophagus, and significant pulmonary symptoms. Patients undergoing Stretta are highly satisfied and have improved GERD symptoms and quality of life comparable to LF. The Stretta procedure is an effective alternative to LF in well-selected patients.


Journal of Laparoendoscopic & Advanced Surgical Techniques | 2001

Initial Experience with the Stretta Procedure for the Treatment of Gastroesophageal Reflux Disease

William O. Richards; Stefan Scholz; Leena Khaitan; Kenneth W. Sharp; Michael D. Holzman

BACKGROUND The Stretta device (Curon Medical, Sunnyvale, CA) is a balloon-tipped four-needle catheter that delivers radiofrequency (RF) energy to the smooth muscle of the gastroesophageal junction. It can be used for the endoscopic treatment of gastroesophageal reflux disease (GERD). PATIENTS AND METHODS Data prospectively collected on the first 25 consecutive patients undergoing the Stretta procedure at Vanderbilt University Medical Center between August 2000 and March 2001 are reported. Patient evaluation included esophageal manometry, ambulatory 24-hour pH testing, a standard GERD-specific quality-of-life survey (QOLRAD), a general quality-of-life survey (SF12), and endoscopy. Stretta surgery was performed following a standardized protocol. Thermocouple-controlled RF energy was delivered to the lower esophageal sphincter (LES) after endoscopic location of the z-line. Patients were followed up 3 months after endoscopic treatment. Results are presented as mean +/- SEM. RESULTS Prior to treatment, patients had a mean DeMeester score of 31.0+/-11.4, an LES pressure of 24+/-2 mm Hg, and normal esophageal peristalsis. Of the 25 outpatient procedures, 19 were done under conscious sedation and 6 under general anesthesia. There was a small learning curve (76+/-8 min for the first three procedures; 50+/-2 min for the subsequent 22). The mild to moderate pain during the first 24 postoperative hours was controlled with over-the-counter medication. Two complications were noted: one patient presented with ulcerative esophagitis and gastroparesis 10 days after the Stretta treatment, and one patient developed pancreatitis on postoperative day 27, which was probably unrelated to the Stretta procedure. Eight of the thirteen patients (62%) available for 3-month follow-up were off all antisecretory medication. The other five patients were still taking medications but had been able to reduce the amount considerably. The average daily dose of proton pump inhibitors was 43.0+/-5.0 mg/preoperatively and 6.4+/-2.2 mg/3 months postoperatively (P < 0.001). Other classes of GERD treatment such as metoclopramide had been completely abandoned. In all patients, QOLRAD scores improved (3.5+/-0.4 to 5.5+/-0.5; P < 0.001) as did SF12 physical (23.7+/-3.0 to 31.0+/-3.4; P < 0.008) and mental (40.5+/-2.9 to 47.7+/-3.2, P < 0.017) scores. All patients would undergo a Stretta procedure again except one 78-year-old man with progressive Alzheimers disease. CONCLUSION The Stretta procedure is a promising new modality in the management of GERD. It can be safely performed in one short session with gastroesophageal endoscopy under conscious sedation in an outpatient setting. It improves GERD symptoms and quality-of-life scores in patients at 3 months and eliminates or significantly reduces the need for antisecretory drugs.


Surgical Endoscopy and Other Interventional Techniques | 1999

Prevalence of gastroesophageal reflux after laparoscopic Heller myotomy

William O. Richards; Ronald H. Clements; P. C. Wang; Christopher D. Lind; H. Mertz; Jk Ladipo; Michael D. Holzman; Kenneth W. Sharp

AbstractBackground: There is still some controversy over the need for antireflux procedures with Heller myotomy in the treatment of achalasia. This study was undertaken in an effort to clarify this question. Methods: To determine whether Heller myotomy alone would cause significant gastroesophageal reflux (GER), we studied 16 patients who had undergone laparoscopic Heller myotomy without concomitant antireflux procedures. Patients were asked to return for esophageal manometry and 24-h pH studies after giving informed consent for the Institutional Review Board (IRB)-approved study at a median follow-up time of 8.3 months (range, 3–51). Results are expressed as the mean ± SEM. Results: Fourteen of the 16 patients reported good to excellent relief of dysphagia after myotomy. They were subsequently studied with a 24-h pH probe and esophageal manometry. These 14 patients had a significant fall in lower esophageal sphincter (LES) pressure from 41.4 ± 4.2 mmHg to 14.2 ± 1.3 mmHg, after the myotomy (p < 0.01, Students t-test). The two patients who reported more dysphagia postoperatively had LES pressures of 20 and 25 mmHg, respectively. Two of 14 patients had DeMeester scores of >22 (scores = 61.8, 29.4), while only one patient had a pathologic total time of reflux (percent time of reflux, 8%). The mean percent time of reflux in the other 13 patients was 1.9 ± 0.6% (range, 0.1–4%), and the mean DeMeester score was 11.7 ± 4.6 (range, 0.48–19.7). Conclusions: Laparoscopic Heller myotomy is effective for the relief of dysphagia in achalasia if the myotomy lowers the LES pressure to <17 mmHg. If performed without dissection of the entire esophagus, the laparoscopic Heller myotomy does not create significant GER in the postoperative period. Clearance of acid refluxate from the aperistaltic esophagus is an important component of the pathologic gastroesophageal reflux disease (GERD) seen after Heller myotomy for achalasia. Furthermore, GERD symptoms do not correlate with objective measurement of GE reflux in patients with achalasia. Objective measurement of GERD with 24 h pH probes may be indicated to identify those patients with pathologic acid reflux who need additional medical treatment.


Annals of Surgery | 1993

Improved survival with neoadjuvant therapy and resection for adenocarcinoma of the esophagus.

James R. Stewart; Steven J. Hoff; David H. Johnson; Michael J. Murray; Dean R. Butler; Charles C. Elkins; Kenneth W. Sharp; Walter H. Merrill; John L. Sawyers

ObjectiveThis study sought to determine the impact of preoperative chemotherapy and radiation therapy (neoadjuvant therapy) followed by resection in patients with adenocarcinoma of the esophagus. Summary Background DataLong-term survival in patients with carcinoma of the esophagus has been poor. An increase in the incidence of adenocarcinoma of the esophagus has been reported recently. MethodsFifty-eight patients with biopsy-proven adenocarcinoma of the esophagus treated at this institution from January 1951 through February 1993 were studied. Since 1989, 24 patients were entered prospectively into a multimodality treatment protocol consisting of preoperative cisplatin, 5-fluorouracil (5-FU), and leucovorin with or without etoposide, and concomitant mediastinal radiation (30 Gy). Patients were re-evaluated and offered resection. ResultsThere were no deaths related to neoadjuvant therapy and toxicity was minimal. Before multimodality therapy was used, the operative mortality rate was 19% (3 of 16 patients). With multimodality therapy, there have been no operative deaths (0 of 23 patients). The median survival time in patients treated before multimodality therapy was 8 months and has yet to be reached for those treated with the neoadjuvant regimen (> 26 months, p < 0.0001). The actuarial survival rate at 24 months was 15% before multimodality therapy and 76% with multimodality therapy. No difference in survival was noted in neoadjuvant protocols with or without etoposide (p = 0.827). ConclusionsMultimodality therapy with preoperative chemotherapy and radiation therapy followed by resection appears to offer a survival advantage to patients with adenocarcinoma of the esophagus.

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Dive into the Kenneth W. Sharp's collaboration.

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Michael D. Holzman

Vanderbilt University Medical Center

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Benjamin K. Poulose

Vanderbilt University Medical Center

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Sharon Phillips

Vanderbilt University Medical Center

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William H. Nealon

Vanderbilt University Medical Center

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Rebeccah B. Baucom

Vanderbilt University Medical Center

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Jesse M. Ehrenfeld

Vanderbilt University Medical Center

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Richard A. Pierce

Vanderbilt University Medical Center

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Jenny Ousley

Vanderbilt University Medical Center

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Joan L. Kaiser

Vanderbilt University Medical Center

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