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A Eitan

Publications and source records attributed to A Eitan.

At least 19 recordsLinked to original sources

Power spectral analysis of heart rate variability during positive pressure pneumoperitoneum: the significance of increased cardiac sympathetic expression.

BACKGROUND: Positive pressure pneumoperitoneum (PPP) effects on the autonomic nervous system (ANS) might be of clinical importance, as imbalance in the autonomic cardiac control might lead to serious consequences. METHODS: Fifteen healthy patients undergoing elective laparoscopic cholecystectomy were analyzed for cardiac autonomic nervous activity by spectral heart rate variability, during awake state, before and after intubation, during CO2 PPP (14 mmHg), and after CO2 evacuation. The very low, low, high and very high frequency (VLF, LF, HF, VHF respectively) bands of the spectral density of the heart rate variability (HRV) and their normalized values, as well as the LF/HF ratio, were obtained from the power spectra of R-R intervals, using the fast-Fourier transformation algorithm. RESULTS: Using Friedman's nonparametric test, only the difference between the power of LF during anesthesia (median 30.74) and the middle of PPP (median 195.66) was found to be significant (p<0.012). Such change was recorded in 14 patients (p = 0.001, sign test). CONCLUSIONS: Increased LF power reflects sympathetic cardiac activation. As the LF range accounts for regulation of blood pressure and baroreflex, several mechanisms may explain this activation. This in turn may predispose patients who suffer from cardiac disease to higher risk of developing ventricular arrhythmias, besides the possible adverse hemodynamic consequences of PPP.

Adult↗

The laparoscopic approach to abdominal hydatid cysts: a prospective nonselective study using the isolated hypobaric technique.

HYPOTHESIS: The laparoscopic isolated hypobaric technique that we developed and use is safe and feasible for almost all kinds of hepatic and extrahepatic abdominal hydatid cysts. DESIGN: A case series. PATIENTS: Between August 1992 and December 1999, 31 patients with no selection criteria underwent 32 consecutive laparoscopic operations for 52 symptomatic hydatid cysts located in the liver (49), spleen (1), and pelvis (2). Eleven patients underwent surgery for between 2 to 5 cysts. INTERVENTIONS: The main surgical maneuvers (puncture, parasite neutralization, and complete evacuation) were performed through an assembled transparent cannula, in which a vacuum was created, while its tip adhered firmly to the cyst wall. Following evacuation of the cyst contents, we attempted to perform partial pericystectomy, omentoplasty, and closed-suction drainage. MAIN OUTCOME MEASURES: Surgical complications and postoperative disease recurrence. RESULTS: Mean cyst diameter was 8.4 cm (range, 3.5-25 cm). Seven cysts were subdiaphragmatic, and 6 were on the posterior (hidden) aspect of the liver. Mean postoperative follow-up was 49 months. Forty-one cysts contained live parasites, and 11 were secondarily infected. Twenty-four cysts were complex. Perioperative complications occurred in 5 patients, including 1 patient who died 1 month after surgery owing to Candida sepsis. Mean hospital stay was 6 days. No evidence of recurrence was recorded during follow-up. CONCLUSIONS: The isolated hypobaric laparoscopic technique described provides a safe and efficacious approach to almost all types of abdominal hydatid cysts and takes advantage of the recognized benefits of the laparoscopic approach.

Adolescent↗

Pain relief in major trauma patients: an Israeli perspective.

BACKGROUND: The pain of major trauma patients remains often unrelieved while in the emergency department. Our objective was to examine pain management in several trauma units, and to evaluate the impact of implementation of a trauma pain management protocol. METHODS: Current status was evaluated from questionnaires filled by trauma unit personnel of nine medical centers. In one, a pain management protocol was introduced. Staff and patients evaluated pain management before and after the protocol was instituted. RESULTS: About 80% of staff respondents from various centers were not aware of guidelines for pain management in trauma. The belief that pain assists diagnosis was the main reason (78.6%) for withholding analgesia. Large variability existed on what contraindicates analgesia, with the majority withholding analgesia in abdominal and multiple injuries. When administered, analgesia was delayed, and most commonly intramuscular meperidine was given. After the protocol's implementation, the personnel's awareness of analgesia increased, and consequently it was administered earlier and to more patients, mostly as intravenous morphine. Patients appreciated the timely analgesia (38% after vs. 14% before, p = 0.01), with fewer receiving none. Analgesia was considered beneficial by more patients (70% after vs. 23% before, p < 0.001), and enhanced cooperativity with personnel (p < 0.001). This was reflected in increased overall satisfaction with pain relief during the entire hospitalization. CONCLUSION: The importance of pain management protocols in major trauma was demonstrated by the response of personnel and patients.

Analgesics↗

Evaluation of seprafilm and amniotic membrane as adhesion prophylaxis in mesh repair of abdominal wall hernia in rats.

INTRODUCTION: Adhesion formation following abdominal wall hernia repair with prosthetic mesh may lead to intestinal obstruction and enterocutaneous fistula. Physical barriers, namely, human amniotic membrane (HAM) or Seprafilm (Genzyme, Cambridge, Mass., USA), a bio-absorbable, translucent membrane composed of carboxymethylcellulose and hyaluronic acid, have been reported to prevent postsurgical intra-abdominal adhesions. OBJECTIVE: Evaluating the effect of HAM and Seprafilm in preventing adhesion formation in the rat model of ventral hernia repair with polypropylene mesh (PPM). MATERIAL AND METHODS: Sixty female Sprague-Dawley rats were divided into three groups. A full-thickness abdominal wall defect was created in each animal. Control animals had the PPM sutured into the defect, whereas in the other two groups, either HAM or Seprafilm were laid over the abdominal viscera before the repair with PPM. Half of the animals in each group were sacrificed on the 21st postoperative day. The remaining rats of the same group were re-operated on the 42nd day for investigation and measurement of the adhesion area in relation to the graft area. RESULTS: Direct mesh repair showed 52.8 and 56% area adhesion formation 3 and 6 weeks postoperatively, respectively. The HAM barrier covered with mesh repair demonstrated 0 and 0.96% area adhesion formation, and the Seprafilm-covered mesh repair showed 0 and 0% area adhesion formation 3 and 6 weeks postoperatively, respectively. Uncovered mesh showed a significantly larger adhesion area than both covered mesh (p = 0.001 and 0.001). Both HAM and Seprafilm were equally effective in preventing postoperative adhesions. CONCLUSIONS: HAM and Seprafilm proved to be an effective antiadhesive barrier in PPM repair of abdominal wall hernia.

Abdomen↗

Pelvic actinomycosis presenting as ureteric and rectal stricture.

BACKGROUND/AIMS: Simultaneous ureteric and rectal stricture due to pelvic actinomycosis is very rare and only a few cases of either rectal or ureteric stricture have been reported. Our aim is to report a case of stricture of the rectum and the right ureter due to pelvic actinomycosis infection in a 63-year-old man. METHODS: Explorative laparotomy and biopsies of the inflammatory pelvic mass were the only procedures that led to the definitive diagnosis of actinomycosis. Temporary diverting colostomy, drainage of the right ureter by a pigtail catheter and postoperative treatment with appropriate antibiotics were successful in eradicating the inflammatory process. CONCLUSIONS: Extensive pelvic masses involving pelvic viscera should be biopsied before undertaking any major surgery because of the possibility of pelvic actinomycosis.

Actinomycosis↗

The role of endoscopic retrograde cholangiopancreatography in the laparoscopic era.

BACKGROUND: The optimal approach to patients with suspected common bile duct (CBD) stones remains unsettled. Options include pre- and postoperative endoscopic retrograde cholangiopancreatography (ERCP) or laparoscopic exploration of the CBD. This retrospective study evaluates the role of ERCP in the management of suspected CBD stones, with an emphasis on indications, endoscopic findings, and outcome. METHODS: We retrospectively reviewed the consecutive medical records of 99 patients (67 females and 32 males) who underwent ERCP for suspected CBD stones between March 1992 and December 1995. RESULTS: In 86 patients, ERCP was performed preoperatively. Indications for ERCP included jaundice, pancreatitis, elevated liver functions tests (LFT), and ultrasound (US) or computed tomography (CT) scan findings. Forty one (48%) of 86 preoperative ERCP had positive findings; 37 (43%) were negative, and in 8 (9%) we failed to demonstrate the CBD. There were seven (8%) major complications: four cases of acute pancreatitis, one case of acute bleeding, and two cases of acute bleeding with perforation. There was no mortality. When pancreatitis was the only indication for ERCP, 0 of 8 patients had positive findings in comparison with 50% when pancreatitis was associated with jaundice and LFT, and 93% when US or CT scan demonstrated stones or dilation of the CBD. CONCLUSIONS: We conclude that ERCP is a valuable option for management of CBD stones but should be performed selectively. Neither pancreatitis alone nor LFT alone is an indication for ERCP. The presence of CBD stones is more likely when multiple indications are present.

Adult↗

A simplified laparoscopic technique for mesh placement in ventral hernia repair.

The use of a large synthetic mesh for laparoscopic repair of significant ventral abdominal wall defects may be accompanied by technical difficulties resulting from improper orientation and positioning of the mesh over the defect. We suggest a technique based on initial fixation of the mesh center to the central point of the defect, and subsequent centrifugal attachment of the mesh to the abdominal wall. This technique is advantageous because it leads to precise orientation and positioning of the synthetic patch and to significant reduction of the time needed for its reinforcement over and around the defect.

Hernia, Ventral↗

The impact of patient delay and physician delay on the outcome of laparoscopic cholecystectomy for acute cholecystitis.

BACKGROUND: Laparoscopic cholecystectomy is now used in the management of acute cholecystitis. Under these circumstances unfavorable conditions may result in conversion and complications. Information about these conditions may help in planning the laparoscopic approach or in proceeding directly to open cholecystectomy. This study was initiated to evaluate perioperative factors associated with conversion and complications of laparoscopic cholecystectomy in acute cholecystitis. Special attention was paid to the duration of complaints until surgery, to the delay on the part of the patient, and to the delay on the part of the physician. METHODS: Between January 1994 and December 1997, we attempted to perform laparoscopic cholecystectomy on 348 patients with acute cholecystitis. All perioperative data were collected on standardized forms. RESULTS: There were 182 cases (52%) of acute uncomplicated cholecystitis, 90 (26%) of gangrenous cholecystitis, 33 of hydrops (9.5%), and 43 of empyema of the gallbladder (12.5%). Seventy six patients (22%) needed conversion to open cholecystectomy and complications occurred in 57 cases. Advanced cholecystitis was associated with significant patient delay (P = 0.01), and it had a significantly higher conversion rate (39%) compared with early cholecystitis (14.5%); (P <0.00001). Conversion rates were also associated with male gender (P = 0.0017), a history of biliary disease (P = 0.0085), and a patient delay of >48 hours (P = 0.028). The total and infectious complication rates were associated with an age older than 60 years (P = 0.023 and 0.007, respectively) and male gender (P = 0.026 and 0.014, respectively). CONCLUSIONS: In acute cholecystitis, patient delay is associated with a high conversion rate. Early timing of laparoscopic cholecystectomy tends to reduce the conversion rate, as well as the total and the infectious complication rates. Male gender, a history of biliary disease, and advanced cholecystitis are associated with conversion. Male and older patients are associated with a high total and infectious complication rates.

Acute Disease↗

Laparoscopic repair of paracolostomy hernia.

Paracolostomy hernia is a common complication of stoma creation. Operative repair is indicated in about 15% of cases, through several surgical approaches. We describe a laparoscopic technique used to repair a large symptomatic paracolostomy hernia in a 69-year-old woman almost 20 years after abdominoperineal resection. The laparoscopic approach to such a hernia is feasible, safe, and logical, as it combines the advantages of mesh reinforcement with those of endoscopic repair.

Aged↗

Laparoscopic splenopexy of a wandering spleen.

A laparoscopic technique for splenopexy of a wandering spleen using an absorbable mesh in an adult woman is described for the first time. This patient was referred to surgery because of recurrent biliary colic secondary to cholecystolithiasis. The wandering spleen had been diagnosed at least 4 years earlier, but a conservative approach had been adopted for a symptomless patient. Laparoscopic cholecystectomy was performed concomitantly with splenopexy. Laparoscopic splenopexy seems a feasible and safe procedure, especially when performed by experienced laparoscopic surgeons.

Adult↗

Use of endoscopic trocar-cannula for chest drain insertion in trauma patients and others.

BACKGROUND: The insertion of a chest drain into the pleural space is a common procedure used for treatment in various intrathoracic abnormalities. Recently, a new technique for chest-tube insertion for pleural cavity drainage, using the disposable endoscopic trocar-cannula, was described for the treatment of some pathologic conditions. METHODS: In a prospective study, we used this technique in the treatment of patients with chest trauma, spontaneous and iatrogenic pneumothorax, and various kinds of pleural effusion. RESULTS: One hundred twelve patients were treated by using the endoscopic trocar-cannula for tube insertion into the pleural cavity. Among them, 39 patients were treated after blunt and penetrating chest trauma. Most cannulae were of 10 to 11 mm in diameter, which enabled the insertion of large-bore drain tubes. In five trauma patients, chest-tube insertion was done successfully without antecedent chest x-ray films. The complication rate was 0.89% for intrapulmonary positioning of a chest tube in a patient who had previous ipsilateral thoracic surgery. CONCLUSION: The use of endoscopic trocar-cannulae for chest-tube insertion is a safe, simple, and effective technique for management of trauma and other diverse intrathoracic abnormalities. Its use outside the hospital should be further studied.

Adolescent↗

Laparoscopic approach to hydatid liver cysts. Is it logical? Physical, experimental, and practical aspects.

BACKGROUND: In recent years attempts have been made to treat hydatid liver cysts laparoscopically. The purpose of this study was to evaluate different aspects of this approach and to examine whether a reasonable model could be developed. METHODS: Three different subjects were analyzed. In the first, physical aspects related to transmembrane pressures were analyzed to demonstrate that evacuation of the cyst under pneumoperitoneum does not carry increased risk of spillage, and may even offer an advantage when the proper technique is used. In the second subject, an isolated liver model of a goat was used to study several techniques for evacuating hydatid cysts without spillage. This was tested qualitatively by demonstrating scolices in the fluid medium around the isolated liver after surgical manipulations. In the third subject, the implication of the technique was evaluated in human patients. RESULTS: According to basic physical assumptions, the following conclusions were reached: (1) The increase in intracystic pressure is equal to or less than the increase in intraperitoneal pressure after pneumoperitoneum. (2) Aspiration of parasitic cysts by laparoscopic needle through a large cannula under "vacuum" or by sealing the cannula and adhering it to the liver by cyanoacrylate or fibrin glue was found to be very safe. Simple needle aspiration failed to prevent spillage. (3) A new transparent cannula 18 mm in diameter with a beveled tip was designed that enables good accessibility to liver cysts and safe evacuation even of huge and complex cysts. CONCLUSIONS: The novel technique to manage hydatid liver cysts, described in the study, is feasible, sensible, and safe. The isolated goat liver containing hydatid cysts can be used as a reliable animal model to test new techniques in the future.

Animals↗

Laparoscopic cholecystectomy for acute cholecystitis performed by residents in surgery: a risk factor for conversion to open laparotomy?

Recent observations point to a seemingly high conversion rate to laparotomy in cases of laparoscopic operations for acute cholecystitis that are performed by surgical residents. The purpose of the study is to evaluate those observations. In a retrospective nonrandomized study, conducted between February 1992 and December 1997, 285 laparoscopic operations for acute cholecystitis were analyzed. Those performed by attending surgeons were compared with those performed by residents assisted by attending surgeons. Of 123 laparoscopic operations performed by laparoscopic surgeons between February 1992 and September 1995, 20.3% were converted to laparotomy, compared with 41.3% of the 29 operations performed by the residents (p < 0.017), with no increase in complication rate. Factors like male sex, duration of upper abdominal pain, and severity of the inflammatory process were not significantly different in both groups. The residents' seniority did not influence the conversion rate. A constant and significant decrease in conversion rate to laparotomy was observed over the course of time, as the study proceeded to December 31, 1997 (p < 0.01). We conclude that the performance of difficult laparoscopic cholecystectomy by residents with the assistance of attending surgeons is feasible, but carries a higher conversion rate to laparotomy for reasons that are not entirely clear. The possibility of a learning curve of the residents is suggested.

Acute Disease↗

Imaging supramolecular aggregates in bile models and human bile.

Investigation of cholesterol crystallization is essential for the understanding of gallstone formation. Previous work has revealed a variety of aggregates of different sizes and shapes prior to the appearance of "classical" plate-like cholesterol monohydrate crystals both in native biles and model systems. In this article, we review existing data based on various microscopic techniques and present data on microstructural pathways leading to cholesterol crystal formation in two different bile models and in native bile. In continuation of our recent investigation of microstructures in nucleating human bile, we now present data suggesting that polymorphism is not limited to complex native bile, but also appears in two, simplified model systems. These studies employed cryo-transmission electron microscopy (cryo-TEM) and video-enhanced light microscopy, using Nomarski optics (VELM). Only the combined use of these two complementary, non-perturbing direct methods can cover the whole range of microstructures ranging from a few nanometers to several microns. Concentrated isotropic solutions of bile models, composed of cholesterol, lecithin and taurocholate, were diluted to induce cholesterol supersaturation and start an evolution of microstructures, leading to cholesterol crystallization. Initially, small spheroidal micelles were observed by cryo-TEM. Subsequently, uni-, oligo- and multilamellar vesicles, compatible with structures seen at the same time by VELM, appeared in coexistence with micelles. Thereafter, during a dynamic phase of cholesterol crystallization, filaments, tubular and helical microstructures, as well as classical plate-like cholesterol monohydrate crystals were noted by light microscopy. Eventually, large plate-like crystals were observed by VELM, while cryo-TEM revealed only small spheroidal micelles. The crystallization process in native human bile during ex vivo incubation was found to bear close resemblance to the findings in the model systems, further supporting the applicability of these systems to the exploration of microstructural aspects of nucleating human bile.

Bile↗

Laparoscopic management of lumbar hernia.

We describe (for the first time) a laparoscopic approach to repair an acquired superior triangle lumbar hernia in a morbidly obese woman by using prosthetic mesh. Such a technique provides an excellent anatomic view, thus avoiding injury to structures in proximity to the hernia during repair; eventually the well-known advantages of such approach result.

Female↗

Experimental study in bile duct-ligated rats of vasopressin and preoperative volume loading to prevent hypotensive crises.

BACKGROUND: Systemic hypotension may result in postoperative renal failure in jaundiced patients. Attenuated responsiveness to catecholamines and hypovolaemia has been reported in jaundiced animals and may be a mechanism contributing to the increased susceptibility of jaundiced patients to haemorrhagic shock. This suggests that an alternative to vasoactive amines to control perioperative hypotension could be desirable. METHODS: This study evaluated the pressor response to vasopressin in normovolaemic 3-day bile duct-ligated rats and in 3-day bile duct-ligated rats after an acute controlled haemorrhage. It also evaluated the response after volume loading with 0.9 per cent saline, 7.5 per cent saline, colloid and mannitol before controlled haemorrhage. In addition, blood volume was measured using radiolabelled albumin. All the data obtained from bile duct-ligated rats were compared with data from sham-operated animals. RESULTS: Attenuated pressor responses to vasopressin were not observed in either normotensive bile duct-ligated rats or in the bile duct-ligated rats subjected to controlled haemorrhage. Volume loading with the four fluids over the dosing range 2.5-7.5 microliters per g body-weight in bile duct-ligated rats reversed the susceptibility to haemorrhagic hypotension. CONCLUSION: Although no reduction in blood volume was demonstrated, bile duct-ligated rats may have a reduced effective blood volume manifesting itself as a latent hypovolaemia and/or tendency to hypotension. Preoperative fluid loading could be beneficial because it corrects hypovolaemia and improves cardiovascular function, as well as improving the cardiovascular response to haemorrhage.

Animals↗

Laparoscopic management of acute cholecystitis. Prognostic factors for success.

BACKGROUND: Laparoscopic cholecystectomy for acute cholecystitis is considered feasible and safe, but it is associated with a higher rate of conversion to laparotomy than elective cholecystectomy because of technical reasons and anatomical changes related to the inflammatory process. The value of several factors that might influence its successful completion has not been studied completely yet, including the role of residents in operating such cases under attending-surgeon surveillance. METHODS: In a retrospective nonrandomized study, the medical charts of 182 patients that were operated for acute cholecystitis (94 of whom via the laparoscopic approach) were studied. The study was also conducted to study the effect of residents as operators. RESULTS: Male sex, duration of right upper abdominal pain, and the severity of the inflammatory process have all been significantly and independently correlated with increased conversion rate to laparotomy. Operation time was not longer than that of the open approach, and hospital stay and complication rate were lower. Operations performed by residents were associated with twofold conversion rate to laparotomy, without increased complication rate (p < 0.012). CONCLUSIONS: Laparoscopic management of acute cholecystitis is feasible and safe. Considering the factors discussed above, lowering the threshold for conversion is necessary in selected cases to maintain low morbidity rate. Integrating laparoscopic cholecystectomy for acute cholecystitis into surgical residency should be studied.

Acute Disease↗

Are the morphology of papillary thyroid carcinoma and the tumour's behaviour correlated?

Six cases of papillary thyroid carcinoma showing clinically highly aggressive behaviour by invading the upper airway and digestive tract structures were retrospectively reviewed to evaluate the morphological variants of the tumours. Four of them were found to be pure papillary and one was a mixed-papillary and follicular-variants regarded as non-aggressive. Only one case was found to be tall cell variant-regarded as an aggressive variant of papillary thyroid carcinoma. The findings suggest that the prognosis of papillary thyroid carcinoma cannot be predicted from its morphological variant and attention should be given to other clinical parameters.

Aged↗