Abstract:
The invention is a method of lowering the gastroesophageal junction below the diaphragm of a patient with a hiatal hernia during the performance of surgical procedures performed via natural orifices. The method comprises applying positive pressure ventilation with positive end expiratory pressure (PEEP) to the patient.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention is related to the field of surgical procedures which are performed via natural orifices. Specifically the invention relates to the field of endoluminal or natural orifice surgical procedures carried out on the stomach or esophagus. 
       BACKGROUND OF THE INVENTION 
       [0002]    Sliding hiatal hernia (HH) is not a disease but is a normal consequence of aging. The gap between the crura of the diaphragm, through which the esophagus passes, tends to enlarge with age, and up to 70% of the population over the age of 70 has hiatal hernias of this sort. In some patients that suffer from Gastro Esophageal Reflux Disease (GERD), the HH slides into the chest, thus, GERD is considered to be caused by the HH. Therefore, in a surgical procedures (laparoscopically or open fundoplication) for such patients, the HH will also be corrected. 
         [0003]    In normal breathing, the air moves into the lungs because the pressure in the chest is negative, consequently, the pressure in the abdominal cavity is higher than the pressure in the chest. When the hiatus is enlarged, the negative pressure inside the chest pulls the stomach up through the gap each time the person takes a breath. When the person exhales, if he/she is lying down, the stomach may stay up; but, if he/she is standing, it is pulled down by gravity and slides back down. 
         [0004]    When trying to perform a medical procedure involving the stomach or esophagus, e.g. a fundoplication, surgical treatment of morbid obesity, correction of a hiatal hernia, or removal of part or parts of the stomach, on a patient who is breathing spontaneously, and is lying supine, a HH often causes a problem which must be dealt with by returning the stomach to its correct anatomical position beneath the diaphragm and keeping it there during the course of the procedure and thereafter. 
         [0005]    In U.S. Pat. No. 7,156,863 by the same applicant, the description of which, including publications referenced therein, is incorporated herein by reference, is described an endoscopic method of performing a fundoplication for the treatment of gastroesophageal reflux disease (GERD). In this procedure the wall of the fundus of the stomach is pushed up against the esophagus and is attached to it. The preferred place to attach the tissue of the fundus to that of the esophagus is about 3-5 cm above the junction between the esophagus and the stomach, i.e. the gastroesophageal junction or Z-line. In the case of a patient with HH, this might not be possible unless some way is found to keep the stomach from being pulled up through the hiatus as the patient breathes. 
         [0006]    Many different ways for accomplishing this by grabbing the tissue of the stomach or esophagus or both and pulling the grabbed tissue to the desired position are known in the art. For example WO 2007/022029 describes a device used to create a gastroesophageal flap restoration. The device has a plurality of orifices distributed about the outer surface of a part of the longitudinal insertion member When the insertion member is inserted into the esophagus to the desired depth relative to the Z-line, vacuum is applied through the orifices to hold the inner wall of the esophagus to the outside of the insertion member. The insertion member is then pushed downward to correct the hernia and the procedure is then carried out. 
         [0007]    It is a purpose of the present invention to provide a simple, safe method of preventing the junction of the stomach and the esophagus to slide into the chest in patients with HH during the performance of surgical procedures carried out on the stomach or esophagus. 
         [0008]    Further purposes and advantages of this invention will appear as the description proceeds. 
       SUMMARY OF THE INVENTION 
       [0009]    The invention is a method of lowering the gastroesophageal junction below the diaphragm of a patient with a sliding hiatal hernia during the performance of surgical procedures performed via natural orifices. The method comprises applying positive pressure ventilation with positive end expiratory pressure (PEEP) to the patient. The method may also comprise tilting the operating table slightly downwards. In an embodiment a PEEP of 5-10 mmHg is applied during the entire course of the procedure. 
         [0010]    A large variety of medical procedures can be performed using the method of the invention. For example, after the PEEP has been applied to lower the gastroesophageal junction below the diaphragm, the stomach can be joined to the esophagus by applying fixing means, e.g. clips, sutures, staples, glue; a fundoplication can be performed; the stomach and/or the esophagus can be joined to other organs; a procedure for surgical treatment of morbid obesity may be carried out; a hiatal hernia can be corrected; part or parts of the stomach can be removed; one or more implanted devices can be inserted or attached to the esophagus or the stomach wall; one or more external devices can be attached to the stomach wall; the stomach can be divided by use of an external stapler or an endoscopic stapler or endoscopic suturing machine; and the intestine can be treated or part of it removed. 
         [0011]    A large variety of transgastric medical procedures can be performed using the method of the invention. For example, after the PEEP has been applied to lower the gastroesophageal junction below the diaphragm, an incision is made in the stomach and then: the stomach can be trangastrically joined to the small intestine by applying fixing means, the stomach can be trangastrically, transvaginally, or transrectally divided into two different volumes, a transgastric, transvaginal, or transrectal fundoplication comprising joining the stomach to the esophagus by applying fixing means can be performed. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0012]    The method of the invention is dependent on performing the procedure under general anesthesia. During general anesthesia the patient does not breathe naturally but gets positive pressure ventilation. The air is not sucked into the lungs as in natural breathing, but is pushed into the lungs by the bellows in the ventilator. As a consequence the pressure inside the chest is higher than the pressure in the abdomen and the stomach is pushed down into the abdomen where the surgeon wants it. 
         [0013]    In normal breathing, the pressure is an inverted sinusoidal wave which goes from 0 to minus 5 or 10 mmHg and back to 0. In positive pressure ventilation exhalation is passive. The pressure goes from 0 to about plus 20 mm Hg (even higher, if the lung compliance is poor) and back to  0 . For a patient with normal lungs, the pressure stays at 0 for about ⅖ th  of the cycle. During this rest period, known as the expiratory plateau, the location of the GastroEsophageal (GE) junction in the supine patient is not reliable, particularly when insuflation of air into the stomach increases the abdominal pressure. 
         [0014]    Positive End Expiratory Pressure (PEEP) is a technique used with artificial ventilation to maintain a positive pressure in the airway at the end of the passive exhalation. 
         [0015]    The method of the invention calls for the application of a PEEP of approximately 5-10 mmHg during the part of or the entire course of the procedure. This, optionally combined with tilting the operating table slightly downwards, will pull the Z-line below the diaphragm and ensure that the stomach will remain in the abdomen even when the hiatal gap is large. It is to be noted that higher values of PEEP will also have the same effect, but are not necessary, and may lead to complications. 
         [0016]    Once the HH has been reduced using PEEP as described herein, it is possible to safely carry out medical procedures involving the stomach or esophagus. A non-exclusive list of such procedures includes: joining the stomach to the esophagus by applying piercing, and/or fixing means, e.g. clips, staples, glue, or sutures; different fundoplication procedures (direct endoscopic, transgastric, transvaginal and transrectal); surgical treatments or procedures of morbid obesity; correction of only the hiatal hernia; removal of part or parts of the stomach; inserting or attaching one or more implanted devices to the esophagus or the stomach; inserting or attaching one or more external mechanical and/or electronic devices to the stomach; dividing the stomach by use of an external stapler or an endoscopic stapler; treatment or removal of part of the intestine and attaching the stomach to the small intestine by applying fixing and/or join means. 
         [0017]    Recently transgastric procedures have been proposed by the applicant of the present application and others. For example, U.S. patent applications Ser. Nos. 11/446,740 and 11/825,694 by the same applicant, the descriptions of which, including publications referenced therein, are incorporated herein by reference respectively describe a transgastric method for carrying out a partial fundoplication and devices and methods for treating morbid obesity. The method of the present invention to lower the gastroesophageal junction to its natural location below the diaphragm of the patient with a sliding hiatal hernia and to prevent the abdominal esophagus and the stomach or part thereof to slide into the chest can be readily applied during the performance of transgastric, transvaginal or transrectal procedures. A non-exclusive list of such procedures includes: transgastrically joining the stomach to the small intestine by applying fixing or approximation means; transgastrically, transvaginally, or transrectally dividing the stomach into two different volumes; transgastric treatment or removal of part of the intestine, and transgastric, transvaginal, or transrectal fundoplications comprising joining the stomach to the esophagus by applying fixing (oin) means, e.g. clips, staples, or sutures, 
         [0018]    It should be noted that patients with longstanding large hiatal hernias may have adhesions that may prevent the stomach from sliding down even when the pressure in the chest is positive relative to the abdominal pressure. Therefore, although the method of the invention is applicable for most patients with small (up to 3 or maybe even 4 cm) hiatal hernias, it may not be applicable to all. The patients in whom the hernia will not slide back can easily be identified by taking an upright chest X-ray before the procedure.