Lewis Operation Research Articles

Comments on the publication “Effect of pyloric drainage procedures on gastric passage and bile reflux after esophagectomy with gastric conduit reconstruction by Palmes et al.”

I read with interest the article by Palmes et al. [1] published in this journal. The issue of whether or not to perform a pyloric drainage after esophagectomy and gastric conduit reconstruction has previously been addressed by several investigators with contradictory results. More recently, the hypothesis that omitting pyloric drainage is safe after esophagectomy has been confirmed in a meta-analysis of nine randomised control trials which showed that a pyloroplasty reduced the occurrence of early gastric outlet obstruction but had little effect on mortality, morbidity and late foregut function [2]. The retrospective study by Palmes et al. nicely adds to this controversy by showing that pyloric drainage not only does not improve gastric emptying but it may also favour bile reflux and esophagitis. The multivariate analysis performed by the authors identified pyloric drainage and an anastomosis located below the level of the arch of the azygos vein as the independent risk factors associated with postoperative reflux esophagitis. However, the authors fail to mention that the size of the gastric conduit is another factor that may significantly affect the functional outcome of an esophagectomy. Using a tubularised stomach, as opposed to the whole stomach, may contribute to a faster emptying of the conduit due to reduced gastric wall distensibility and increased endoluminal pressurisation. After the laparoscopic gastric mobilisation has become the standard approach for esophagectomy in my department, I have gradually abandoned the practice of draining the pylorus. Between 2001 and 2007, 65 patients underwent an Ivor Lewis operation through laparoscopy and right thoracotomy for a type 1 or 2 adenocarcinoma of the distal esophagus/cardia according to Siewert classification. The lesser curve was routinely resected preserving the first three to four branches of the right gastric artery, and a 4-cm-wide gastric tube was constructed; in all patients, the esophago-gastric anastomosis was placed at the apex of the right chest. The incidence of clinically significant gastric outlet obstruction was 6.1% (4/65). All these individuals were relieved by a single or multiple sessions (median 2, range 1–3) of endoscopic pneumatic dilatation of the pylorus performed within the first year after the operation. It is noteworthy that Holscher et al. [3], in a recent series of 83 patients undergoing laparoscopic conditioning of the stomach for esophageal replacement, reported a 3.6% incidence of postoperative delayed gastric emptying; all individuals were relieved with endoscopic pneumatic dilation of the pylorus, and their further course was uneventful. In conclusion, I agree that pyloric drainage is not necessary after esophagectomy, provided that a narrow gastric conduit is used to replace the esophagus and the anastomosis is performed at the apex of the right chest. This may prevent duodenogastric reflux, as demonstrated by Palmes et al., and eliminates the potential risks associated to the laparoscopic pyloromyotomy or pyloroplasty. The occasional occurrence of postoperative gastric outlet obstruction can be safely treated by endoscopic pneumatic dilatation of the pylorus. Langenbecks Arch Surg (2008) 393:117–118 DOI 10.1007/s00423-007-0242-x

On the Solvability of Homogeneous Left-Invariant Differential Operators on the Heisenberg Group

We discuss the problem of solvability for the class of homogenoeus left-invariant operators □S,αon the Heisenberg groupHnintroduced by F. De Mari, M. M. Peloso, and F. Ricci. (1995,J. Reine Angew. Math.464, 67–96), whereS∈Sp(C,n) has a degenerated semi-definite real part, andα=±(n+2l),l=0,1,…. We completely characterize the solvable operators in this class. As a consequence we obtain that certain operators □S,αare solvable while their transposest□S,αare not. This is the case, for instance, for the operatorYZonH1, whereZ=X−iYis the unsolvable Lewy operator.

Ivor Lewis operation for epidermoid carcinoma of the esophagus

One hundred patients, 95 men and 5 women with a mean age of 59 years (age range, 35 to 77 years), were treated by the same initiate surgeon in practice from 1982 to 1988 for epidermoid carcinoma of the lower two-thirds of the esophagus using the Ivor Lewis procedure. Fifty-eight tumors were located in the middle third of the esophagus and 42, in the lower third. Postoperative staging revealed 30 stage I / II and 70 stage III carcinomas (ie, tumors extending beyond the esophageal wall or lymph node extension). Operative procedure was considered curative in 70 patients and palliative in 30 patients. The same procedure has been used for all patients. In all patients we were able to perform extended esophagectomy with anastomosis located 3 to 7 cm under the pharyngoesophageal junction. Postoperative mortality was 4%. Morbidity due to leakage was 7%; proper drainage enabled spontaneous healing in 5 patients. Fifteen patients had pulmonary complications, none of which fatal. Median actuarial survival was 17 months. Actuarial survival at 24 months is significantly higher for patients in stage I and II (68.4%) than for patients in stage III (23.2%) ( p < 0.01). The Ivor Lewis procedure is a safe surgical approach for the treatment of the esophageal carcinoma that has a high survival rate and allows a good quality of life.

Sobolev estimates for the Lewy operator on weakly pseudo-convex boundaries

Sobolev estimates for the Lewy operator on weakly pseudo-convex boundaries

An example on the Heisenberg group related to the Lewy operator

An example on the Heisenberg group related to the Lewy operator

Esophagogastrectomy: Superiority of the Combined Abdominal-Right Thoracic Approach (Lewis Operation)

The advantages of the combined abdominal-right thoracic approach to operating upon carcinoma of the esophagus (Lewis operation) are reviewed; they include elimination of the need for incision of the diaphragm or costal arch; easier mobilization of the esophagus; better visualization of the anastomosis through a high thoracotomy incision; and no interference by the heart and aortic arch. The operation is performed in one stage, using separate abdominal (upper midline) and thoracic (excision of the fourth rib) incisions. A careful two-layer anastomosis is performed using a separate circular opening in the stomach and invaginating the esophagus into the stomach by suturing the gastric serosa to the mediastinal fascia and pleura. Important principles of postoperative care include monitoring in the intensive care unit for five to seven days, use of a sump-type nasogastric tube, and frequent measurement of body weight, blood volume, blood gases, and electrolytes. Colloid infusions are preferred to crystalloid solutions in order to avoid fluid overload. Vigorous nasotracheal suction is important, and early tracheostomy is performed if bronchopulmonary secretions tend to accumulate. This operation was performed on 37 unselected patients during a seven-year period without operative mortality or anastomotic leak. Thirty-three patients had metastases at the time of resection, but all were relieved of dysphagia and the degree of palliation was very encouraging.