Search PubMed⌕ Search

Biomedical subjects

D C Brooks

Publications and source records attributed to D C Brooks.

At least 19 recordsLinked to original sources

Endoluminal gastroplication for treatment of patients with classic gastroesophageal reflux symptoms and borderline 24-h pH studies.

BACKGROUND: Patients with classic gastroesophageal reflux disease (GERD) symptoms and borderline 24-h pH studies are not considered to be good candidates for surgical fundoplication. Endoluminal gastroplication (ELGP) is a new endoscopic treatment for patients with GERD. The aim of this study was to evaluate the efficacy of ELGP in these patients. METHODS: Patients with heartburn, regurgitation symptoms and a DeMeester score of less than 30 were studied. ELGP involved placement of two or three plications within 2 cm of the gastroesophageal junction. Clinical outcomes measured were heartburn symptom score (HSS), regurgitation frequency score (RFS) and medication use. RESULTS: Twenty-five patients (11 M, 14 F, mean age of 51 years) had a medication use of 11.5 doses of proton-pump inhibitors per week prior to ELGP. Average lower esophageal sphincter pressure measured 15 +/- 8 mmHg, and average DeMeester score was 18 +/- 8. Nine patients had hiatal hernias and 11 had esophagitis. Twenty-four patients were available for a mean follow-up of 12 months. HSS significantly decreased from 48 to 17 (P < 0.01) and RFS was reduced from 1.8 to 0.7 (P < 0.01). Proton-pump inhibitor use was 5.3 doses per week (P < 0.01) post-ELGP; 12 patients (50%) were off medications, 3 (13%) had a 50% reduction in medication use, and in 9 (37%) there was no change. Complications were bleeding in one patient and aspiration pneumonia in another patient. CONCLUSIONS: Endoluminal gastroplication provides symptomatic relief for patients with classic GERD symptoms despite medical therapy and borderline 24-h pH studies.

Adult↗

What is the value of telerobotic technology in gastrointestinal surgery?

BACKGROUND: Although telerobotic technology has entered clinical application, its value for gastrointestinal surgery is unclear. Our objective was to evaluate the performance characteristics of telerobotically assisted laparoscopic cholecystectomy (TALC). METHODS: All TALCs performed using the da Vinci Surgical System between January 2000 and September 2001 at a tertiary academic medical center were analyzed. RESULTS: For this study, 20 patients (80% female) with a mean age of 47 +/- 4 years underwent TALC. All had symptomatic cholelithiasis, and all had successful TALC results without complications or need for conversion to conventional laparoscopic cholecystectomy (CLP). The mean procedure time was 152 +/- 8 min. The procedures were performed by one of three staff surgeons experienced in laparoscopic surgery who had training in telerobotic surgery. The perceived advantages of TALC over CLP included easier tissue dissection, enhanced dexterity, and stimulated interest in biliary surgery. The disadvantages included increased operating time and lack of tactile feedback. CONCLUSIONS: The TALC procedure is effective and safe when performed by appropriately trained surgeons. Telerobotic technology has the potential to reinvigorate gastrointestinal surgery.

Academic Medical Centers↗

Transitions in laparoscopic cholecystectomy: the impact of ambulatory surgery.

BACKGROUND: Ambulatory laparoscopic cholecystectomy is a common practice in the United States, but its development remains slow in most other countries. The objective of the current study was to report the impact of ambulatory surgery on the practice of laparoscopic cholecystectomy in a major teaching hospital since the inception of the service. METHODS: The hospital database of patients who underwent cholecystectomies for benign hepatobiliary pathologies was reviewed between January 1993 and December 1999. Changes in the practice of laparoscopic cholecystectomy and the length of hospital stay were analyzed. Clinical characteristics of the ambulatory and inpatient groups were compared. RESULTS: Of 2,891 laparoscopic cholecystectomies involved in the current study, 888 (31%) were performed as day cases, and 2,003 (69%) were performed as inpatient laparoscopic cholecystectomies. The annual number of ambulatory laparoscopic cholecystectomies increased from 3 (0.6%) in 1993 to 212 (48%) in 1997. This was followed by a plateau in the next 3 years. The ambulatory group comprised a significantly higher prevalence of young women (87%) who underwent surgery mainly for biliary colic (88%). CONCLUSIONS: The current study demonstrated a net trend toward ambulatory laparoscopic cholecystectomy and a shorter length of hospital stay. Almost half of our patients with gallstone disease currently are using the ambulatory laparoscopic cholecystectomy service, with young women constituting the majority. We predict that ambulatory laparoscopic cholecystectomy heralds the wave of the future, and our experience may serve as a blueprint for other institutions wishing to embark on this journey.

Adult↗

Predictive factors for unanticipated admissions after ambulatory laparoscopic cholecystectomy.

HYPOTHESIS: Analysis of the causes of unanticipated admission after ambulatory laparoscopic cholecystectomy may permit the identification of predictive clinical factors for postoperative admission. DESIGN: Univariate and multivariate analyses of clinical variables associated with unplanned admission in a retrospective case-control series of ambulatory laparoscopic cholecystectomies. SETTING: A major university-affiliated teaching hospital. PATIENTS: Seven hundred thirty-one consecutive patients who underwent ambulatory laparoscopic cholecystectomies between January 1, 1996, and December 31, 1999. INTERVENTION: Ambulatory laparoscopic cholecystectomy. MAIN OUTCOME MEASURES: Unplanned postoperative admissions. Univariate and multivariate analyses of 19 clinicopathologic factors were performed to identify independent predictive factors for these admissions. RESULTS: Seven hundred six patients were discharged on the day of operation. The remaining 25 required admission because of pain (n = 10), nausea and vomiting (n = 6), retention of urine (n = 5), patient preference (n = 3), and medical observation (n = 1), giving an unanticipated admission rate of 3.4%. Significant factors associated with unplanned admission included operative duration of longer than 60 minutes and thickened gallbladder wall on ultrasonographic and pathological findings. By means of logistic regression, length of operation was the only independent predictive factor. Operative time exceeding 60 minutes incurred a 4-fold increased risk for unanticipated admission. CONCLUSIONS: Operative duration was the best predictive factor for unplanned admission after ambulatory laparoscopic cholecystectomy. During selection of patients for day surgery, ultrasonographic demonstration of a thickened gallbladder wall should be taken into consideration.

Adult↗

Extinction and spontaneous recovery of ataxic tolerance to ethanol in rats.

RATIONALE AND OBJECTIVES: Two experiments with rats using an ethanol ataxia method investigated extinction and spontaneous recovery of tolerance. Tolerance extinction has been shown with a variety of drugs and methods, but until now it has not been shown with ethanol ataxia. Extinction was investigated here because of its connection with cue exposure treatments, and also to allow an assessment of spontaneous recovery. Spontaneous recovery is the return of conditioned responses, such as those potentially contributing to tolerance, when time passes after extinction. In terms of response topography it resembles instances of relapse in humans. Its demonstration constitutes one technique for illustrating that the effects of extinction are often temporary. There are no published reports showing a recovery of tolerance to any drug due to the passage of time after extinction. A demonstration of spontaneous recovery contributes to an understanding of the effects and time course of tolerance extinction. It also raises the possibility that spontaneous recovery involving drug tolerance has mechanisms similar those involved in instances of spontaneous recovery studied more extensively with non-drug methods. METHODS: In one experiment, ataxic tolerance was conditioned to a strobelight conditioned stimulus (CS) by exposing rats to the strobelight while experiencing the effects of an ethanol injection. Tolerance was extinguished in 17 or 24 once-daily trials by presenting the strobelight without ethanol (with saline). The effect of those numbers of trials was assessed on the day after extinction in the presence of the strobelight when ethanol was again injected. The effect was compared to the effect of the strobelight and ethanol in naive rats and in rats that had received only tolerance conditioning. In a second experiment, ataxic tolerance was conditioned and then extinguished over 17 trials, just as in the other experiment. Different groups were then tested 1, 12, 18, and 24 days after extinction in the presence of the strobelight when ethanol was again injected. RESULTS: Ataxic tolerance was fully extinguished after either 17 or 24 trials, as shown by comparisons with the naive and conditioning-only controls. Tolerance was greater (it recovered) when the strobelight CS was reintroduced 24, 18, and even 12 days after extinction, compared with testing 1 day after extinction. CONCLUSIONS: Conditioned ataxic tolerance can be extinguished, just as other conditioned tolerances can. More important, the return of tolerance over time after extinction represents spontaneous recovery of ethanol tolerance, and indicates that as in other conditioning preparations, extinction does not result in unlearning of the original conditioning association. The identification of spontaneous recovery of tolerance isolates a robust source of the potential for drug use relapse: the mere passage of time after extinction.

Animals↗

Necrotizing pancreatitis: contemporary analysis of 99 consecutive cases.

OBJECTIVE: To analyze the impact of a conservative strategy of management in patients with necrotizing pancreatitis, reserving intervention for patients with documented infection or the late complications of organized necrosis. SUMMARY BACKGROUND DATA: The role of surgery in patients with sterile pancreatic necrosis remains controversial. Although a conservative approach is being increasingly used, few studies have evaluated this strategy when applied to the entire spectrum of patients with necrotizing pancreatitis. METHODS: The authors reviewed 1,110 consecutive patients with acute pancreatitis managed at Brigham and Women's Hospital between January 1, 1995, and January 1, 2000, focusing on those with pancreatic necrosis documented by contrast-enhanced computed tomography. Fine-needle aspiration, the presence of extraintestinal gas on computed tomography, or both were used to identify infection. RESULTS: There were 99 (9%) patients with necrotizing pancreatitis treated, with an overall death rate of 14%. In three patients with underlying medical problems, the decision was made initially not to intervene. Of the other 62 patients without documented infection, all but 3 were managed conservatively; this group's death rate was 11%. Of these seven deaths, all were related to multiorgan failure. Five patients in this group eventually required surgery for organized necrosis, with no deaths. Of the 34 patients with infected necrosis, 31 underwent surgery and 3 underwent percutaneous drainage. Only four (12%) of these patients died, all of multiorgan failure. Of the total 11 patients who died, few if any would have been candidates for earlier surgical intervention. CONCLUSIONS: These results suggest that conservative strategies can be applied successfully to manage most patients with necrotizing pancreatitis, although some will eventually require surgery for symptomatic organized necrosis. Few if any patients seem likely to benefit from a more aggressive strategy.

Adult↗

Recent and remote extinction cues reduce spontaneous recovery.

Five appetitive conditioning experiments with rats examined the ability of extinction cues (ECs) to reduce spontaneous recovery after extinction procedures that varied the temporal relation between the ECs and the conditioned stimulus (CS) and included presentations of additional events (e.g. other stimuli correlated with extinction, CSs, and the US). In extinction, two different ECs were presented either closely in time before (i.e. recent to), or more distant (i.e. remote) from a nonreinforced CS. Both recent and remote ECs reduced spontaneous recovery to the CS when present during testing (Experiments 1-4). Each EC reduced recovery despite the addition during extinction of a second EC and CS (Experiments 1, 3, and 4), and the US (Experiment 3). Experiments 4 and 5 investigated the recent and remote ECs' tendency to control a serial occasion setting discrimination involving the target CS under explicit training conditions. Neither EC gained such discriminative control. Possible explanations of the results are discussed, including configural learning, occasion setting, and contextual cue control.

Animals↗

Arterial to end-tidal carbon dioxide pressure difference during laparoscopic surgery in pregnancy.

BACKGROUND: There is controversy about whether capnography is adequate to monitor pulmonary ventilation to reduce the risk of significant respiratory acidosis in pregnant patients undergoing laparoscopic surgery. In this prospective study, changes in arterial to end-tidal carbon dioxide pressure difference (PaCO2--PetCO2), induced by carbon dioxide pneumoperitoneum, were determined in pregnant patients undergoing laparoscopic cholecystectomy. METHODS: Eight pregnant women underwent general anesthesia at 17-30 weeks of gestation. Carbon dioxide pnueumoperitoneum was initiated after obtaining arterial blood for gas analysis. Pulmonary ventilation was adjusted to maintain PetCO2 around 32 mmHg during the procedure. Arterial blood gas analysis was performed during insufflation, after the termination of insufflation, after extubation, and in the postoperative period. RESULTS: The mean +/- SD for PaCO2--PetCO2 was 2.4 +/- 1.5 before carbon dioxide pneumoperitoneum, 2.6 +/- 1.2 during, and 1.9 +/- 1.4 mmHg after termination of pneumoperitoneum. PaCO2 and pH during pneumoperitoneum were 35 +/- 1.7 mmHg and 7.41 +/- 0.02, respectively. There were no significant differences in either mean PaCO2--PetCO2 or PaCO2 and pH during various phases of laparoscopy. CONCLUSIONS: Capnography is adequate to guide ventilation during laparoscopic surgery in pregnant patients. Respiratory acidosis did not occur when PetCO2 was maintained at 32 mmHg during carbon dioxide pneumoperitoneum.

Analysis of Variance↗

Laparoscopic cholecystectomy during pregnancy. Review of anesthetic management, surgical considerations.

BACKGROUND: We present our experience with laparoscopic cholecystectomy in pregnant patients, with consideration of the physiological changes of pregnancy affecting anesthetic and surgical management. METHODS: We reviewed the medical records of all pregnant patients undergoing laparoscopic surgery at Brigham and Women's Hospital between January 1, 1991 and April 30, 1995. RESULTS: Laparoscopic cholecystectomy was performed without complication in ten patients (gestational age 9-30 weeks). Details of anesthetic and surgical management are described. The anesthetic and surgical implications of pregnancy-associated physiological changes in the gastrointestinal, respiratory, cardiovascular, and central nervous system are reviewed. CONCLUSIONS: With appropriate attention to the altered physiology of pregnancy, laparoscopic cholecystectomy can be performed safely and effectively during pregnancy.

Adult↗

Laparoscopy for chronic abdominal pain.

BACKGROUND: This purpose of this investigation was to evaluate the utility of laparoscopy in patients with chronic abdominal pain. METHODS: A retrospective review was performed of 34 patients who underwent laparoscopy for chronic abdominal pain. Average patient age was 39 years. The majority were women. Most had undergone abdominal surgery in the past. RESULTS: All procedures were performed laparoscopically. A positive finding was made in 65% of patients. Fifty-six percent of patients underwent adhesiolysis, but 26% required no operative intervention other than laparoscopic exploration. Notably, 73% of patients reported improvement in pain postoperatively, whether or not a positive finding had been made on laparoscopy. CONCLUSIONS: This retrospective study suggests laparoscopy can identify abnormal findings and improve outcome in a majority of selected cases. Recommendations are provided for patient selection. Prior abdominal surgery is not an absolute contraindication to laparoscopic exploration for chronic abdominal pain.

Abdomen↗

Prophylactic antiemetics for laparoscopic cholecystectomy: ondansetron versus droperidol plus metoclopramide.

Two hundred adults undergoing laparoscopic cholecystectomy were enrolled in a prospectively randomized, double-blind investigation comparing ondansetron, 4 mg (Group O) with the combination of droperidol, 0.625 mg, and metoclopramide, 10 mg (Group DM). Antiemetic drugs were administered intravenously (IV) after induction of general anesthesia (propofol, desflurane). Moderate or severe nausea in the postanesthesia care unit was treated with the cross-over drug, i.e., ondansetron for patients in Group DM or droperidol plus metoclopramide for patients in Group O. Data were analyzed using t-tests and chi 2 analyses, with P < 0.05 considered statistically significant. The groups were similar with respect to gender, age, weight, duration of surgery, number receiving intraoperative atropine or ephedrine, number admitted over-night, and time to discharge home. Of 102 patients in Group O, 44 required antiemetics in the postanesthesia care unit, compared with 24 of 98 patients in Group DM (P < 0.01). One patient (in Group DM) was admitted for persistent nausea. In conclusion, droperidol 0.625 mg IV in combination with metoclopramide 10 mg IV was more effective in preventing postoperative nausea than was ondansetron 4 mg IV in patients undergoing laparoscopic cholecystectomy, with no difference in the time to discharge.

Adrenergic Agonists↗

Intraductal mucin-hypersecreting neoplasm "mucinous ductal ectasia": endoscopic recognition and management.

OBJECTIVES: Intraductal mucin-hypersecreting neoplasm (IMHN), also termed mucinous ductal ectasia, is a rare disorder of the pancreas characterized by distension of the pancreatic duct with mucus. This study attempted to clarify the clinical, radiographic, histological, and treatment approaches to this entity. METHODS: The medical records, radiological imaging studies, and pathology specimens of eight patients with IMHN seen during a 3-yr period were reviewed. The diagnosis of IMHN was established by findings during ERCP, which included mucin plugging of the papilla, mucin extrusion from the papillary orifice after intraductal injection of contrast medium, mucinous filling defects in the main pancreatic duct, and dilated main and branch pancreatic ducts in the absence of obstructing ductal strictures. RESULTS: All patients presented with an initial clinical diagnosis of acute or chronic pancreatitis, suspected cystic neoplasm, or biliary obstruction. Noninvasive imaging studies such as transabdominal ultrasonography or CT and laboratory evaluation did not seem to help in defining the disease. Five patients underwent Whipple resection; pathology included papillary ductal hyperplasia in one, dysplastic mucinous epithelium in two, and mucinous cystadenocarcinoma in two. All five patients had associated histological evidence of chronic pancreatitis. All patients are alive and well after 21-53 months without evidence of residual disease. CONCLUSIONS: IMHN has a wide spectrum of clinical, radiological, and histological features. The indolent biologic behavior and favorable prognosis of IMHN suggest that it is one of the most curable forms of pancreatic malignancy.

Adult↗

Patient satisfaction following laparoscopic and open antireflux surgery.

OBJECTIVE: To compare laparoscopic (LNF) with open Nissen fundoplication (ONF) in terms of hospital charges, efficacy, and patient satisfaction. DESIGN: A prospective, nonrandomized study with a median follow-up of 370 days. SETTING: Two tertiary care university hospitals. PATIENTS: Eighty-six patients with complications of gastroesophageal reflux who had not had previous antireflux surgery were studied. Patients chose ONF or LNF following discussion with the surgeon; 12 underwent ONF and 74 underwent LNF, of whom eight required conversion to laparotomy. MAIN OUTCOME MEASURES: Hospital charges, disability, satisfaction, and side effects of fundoplication. RESULTS: Patients were demographically similar. Total charges (mean +/- SD) for LNF ($11,673 +/- $4723) were significantly less than for ONF ($18,394 +/- $17,264). Patients who underwent LNF returned to work sooner (10 +/- 3 days) than those who underwent ONF (28 +/- 1 days). Bloating, dysphagia, and recurrent heartburn occurred with equal frequency in both groups. Recurrent reflex occurred in four of 74 LNF patients and one of 12 ONF patients. Overall satisfaction scores were similar, irrespective of operative technique (LNF, 3.35 +/- 0.87; ONF, 3.50 +/- 0.94. CONCLUSIONS: Laparoscopic Nissen fundoplication is as effective as ONF in the treatment of complications of gastroesophageal reflux disease and appears to cost less and lead to faster recovery from surgery, but does not result in higher patient satisfaction than ONF. The most important factor in patient satisfaction is the abolition of preoperative symptoms rather than the type of operation.

Costs and Cost Analysis↗

The role of the rat hippocampal system in several effects of context in extinction.

The effect of fornix lesions on some effects of manipulating the context on performance in extinction were studied. In renewal, subjects' responding to an extinguished conditioned stimulus (CS) recovered when the CS was presented in the context in which it had been conditioned after extinction in a different context. In reinstatement, it recovered when the CS was tested after independent presentation of the unconditioned stimulus (US; an effect mediated by contextual conditioning.) In spontaneous recovery, it recovered after the passage of time, that is, when the CS was tested in a new temporal context. In the conditioned suppression method, fornix lesions had no effect on conditioning, extinction, renewal, or spontaneous recovery; however, they abolished the reinstatement effect. The results suggest that the hippocampal system may be important in the formation of context-US associations, but not in other types of learning about the context.

Animals↗

Postsurgical bile leaks: endoscopic obliteration of the transpapillary pressure gradient is enough.

OBJECTIVES: Bile leaks are a well documented complication of biliary surgery, occurring more frequently with laparoscopic procedures. Endoscopic therapy with a long biliary endoprosthesis traversing the site of the leak is effective. We have evaluated the hypothesis that equalizing biliary and duodenal pressures with a short transpapillary stent is an equally effective therapy for bile leaks. METHODS: Thirty one consecutive patients presenting over a 52-month period with postsurgical bile leaks were evaluated. Patients had been treated with long endoprostheses (stents or nasobiliary tubes), sphincterotomy, or short transpapillary stents. The success, complication rate, need for additional therapy, and hospitalization time of each therapeutic approach were determined. RESULTS: Endoscopic therapy was successful in all 25 patients in whom a bile leak could be documented. The clinical success, need for radiological drainage, length of hospitalization, and incidence of pancreatitis were similar for all methods of treatment. CONCLUSIONS: These results confirm that endoscopic therapy is highly successful in the treatment of postoperative bile leaks and suggest that the mechanism of healing is the equalization of bile duct and duodenal pressures, allowing flow of bile into the duodenum. The endoscopic placement of short transpapillary stents without sphincterotomy is a temporary, effective, and technically simple method of pressure equalization. This should be considered as the primary therapy for most postoperative bile leaks.

Adult↗

A prospective comparison of laparoscopic and tension-free open herniorrhaphy.

OBJECTIVE: To compare results and outcomes following laparoscopic and tension-free open inguinal herniorrhaphy. DESIGN: A prospective, nonrandomized trial of a single surgeon's experience. SETTING: A large university hospital. PATIENTS: The study included 100 patients with 116 hernias. Patients were offered open hernia repair or, if medically suitable for general anesthesia, a laparoscopic hernia repair. Fifty-seven patients underwent open repair and 43 patients underwent laparoscopic repair. INTERVENTION: Laparoscopic repair was performed using a transabdominal preperitoneal mesh technique. Open hernia repair was performed using a mesh-plug technique in which the hernia sac was reduced and held in place by a cone of mesh. The floor was covered with a second piece of mesh that encircled the cord and was sutured at the internal ring; it was held in place under the external oblique without sutures. RESULTS: Patients undergoing open repair were older than those undergoing laparoscopic repair. The distribution of hernia types was similar. The laparoscopic operation took longer than the open operation (mean [+/- SD], 1.9 +/- 0.4 hours vs 1.6 +/- 0.4 hours; P < .05), was more expensive ($4165 +/- $1154 vs $2985 +/- $1682; P < .05), and required more postoperative admissions (28% vs 3.5%). There were three recurrences in the laparoscopic group and none in the open group. Patients undergoing laparoscopic repair consumed the same amount of narcotic analgesics as did the group undergoing open repair and had discomfort for the same amount of time. Patients undergoing laparoscopic repair returned to work sooner than did patients undergoing open repair (5.6 days vs 10.3 days; P < .05). CONCLUSIONS: Laparoscopic hernia repair returns patients to the workplace faster than open hernia repair despite a similar analgesic requirement. The laparoscopic repair costs more and has a higher recurrence rate than open repair. Laparoscopic repair is most suitable for bilateral hernias. Further investigation of this technique is required before its wide-scale application can be recommended.

Adult↗