Laparoscope Cannula

Abstract

A cannula is provided for laparoscopy, which cannula includes an adjustable cone-shaped sleeve for blocking the incisional gap and maintaining the pneumoperitoneum. The cannula also includes a pair of hooks for receiving a suture to maintain the cannula in place with respect to the patient's abdomen.

Description

BACKGROUND OF THE INVENTION

The laparoscope (peritoneoscope, celioscope) is an important tool of modern gynecologic diagnosis and surgical treatment. A prior art technique of laparoscopy requires the introduction of a needle into the peritoneal cavity to establish a pneumoperitoneum, and the abdominal wall is then punctured with a cannula, bearing a sharp trochar. Both of these steps are performed blindly, and there is thus the possibility of accidentally puncturing a vital organ or a blood vessel. The trochar is subsequently withdrawn, and the lighted laparoscope is inserted through the cannula into the peritoneal cavity for visualization.

Another technique of performing laparoscopy is discussed in my article in the American Journal of Obstetrics and Gynecology, St. Louis, Vol. 110, No. 6, pages 886-887, July 15, 1971. In this technique, a laparoscope cannula with a trumpet valve is fitted with a thin, cone-shaped steel sleeve, mounted on the cannula's shaft. The cone sleeve may be fitted with an extender to accommodate variations in the thickness of the abdominal wall and in the distance between the umbilicus and the symphysis pubis.

The purpose of the conical sleeve is to seal the peritoneal and fascial gap, by advancing the cone deeper through the incisional opening. Although the use of such a cannula has been found generally satisfactory, certain problems were noted. These problems included the occasional occurrence of gas leaks, the need for an assistant to hold the cannula in place while the scope was being withdrawn or manipulated, and the need to use several cannulas of different sizes to accommodate individual variations in the thickness of the abdominal wall.

The present invention is directed toward the obviation of the aforementioned problems.

BRIEF DESCRIPTION OF THE INVENTION

In accordance with the present invention, there is provided a laparoscope cannula which comprises a proximal shaft portion forming the inlet to receive a blunt obturator and a laparoscope; a distal shaft portion for insertion into the abdominal cavity of a patient; and gas valve means coupling the proximal shaft portion and the distal shaft portion. A generally truncated cone-shaped sleeve is positioned on the distal shaft portion, with the base of the cone facing toward the proximal shaft portion. Means are provided for adjustably positioning the sleeve along the distal shaft portion whereby selectively variable length protrusion segments may be provided.

In the illustrative embodiment, the cannula further includes means, such as hooks, carried thereby for receiving a suture, to maintain the cannula in place with respect to the patient's abdomen.

A more detailed explanation of the invention is provided in the following description and claims, and is illustrated in the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a front elevation of a laparoscope cannula constructed in accordance with the principles of the present invention, showing a blunt obturator in dashed line and showing in phantom the possible movement of the sleeve;

FIG. 2 is a top plan view of the left half of the laparoscope cannula shown in FIG. 1;

FIG. 3 is an enlarged, fragmentary, cross-sectional view of the sleeve mounted on the distal shaft portion of the cannula of FIG. 1;

FIG. 4 is a cross-sectional view thereof, taken along the plane of line 4--4 of FIG. 3;

FIG. 5 is a greatly enlarged, fragmentary view of the sleeve and distal shaft coupling; and

FIG. 6 is an elevational view of a conventional blunt obturator.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENT

Referring to FIGS. 1 and 2 in particular, the cannula 10 therein shown includes a proximal shaft portion 12, a distal shaft portion 14, and gas valve means 16 which couple the proximal shaft portion and the distal shaft portion. The shaft portions 12 and 14 are preferably stainless steel or chrome plated steel. Gas valve means 16 comprises a trumpet valve conventionally used in laparoscope cannulas.

At the front of proximal shaft portion 12 there is connected a rubber inlet 18 which defines a central opening that is no smaller than the external diameter of a conventional blunt obturator 20 (FIG. 6) with the front end 22 of inlet 18 being of a size to provide an abutting relationship with end 24 of handle 26 of blunt obturator 20.

Distal shaft 14 defines three grooves 30, 31 and 32 about its circumference. These grooves are spaced and of a size to receive a ring carried by sleeve 34, as described below.

Sleeve 34 is preferably formed of stainless steel or chrome plated steel and is in the form of a truncated cone, with the base 36 facing the proximal shaft portion 12. Base 36 includes an extension 37, to which a rubber washer-type member 38 is connected, to achieve a snug, frictional fit with respect to the outer surface of shaft 14. Cone 34 is selectively locked in place along shaft 14 by means of a C-ring 40 carried within a groove 42 (FIG. 5) defined about the internal circumference of sleeve 34. Ring 40 is fitted within groove 42 to permit ring 40 to ride along the surface of shaft 14 until it overlies a groove 30, 31 or 32, at which time the ring 40 will enter the groove, as shown most clearly in FIGS. 3 and 5.

A pair of hooks 46, 47 are connected to valve 16, to receive sutures in order to maintain the cannula in place during laparoscopy. In this manner, there is no need for an assistant to hold the cannula in place while the scope is manipulated.

The operation is performed in the following manner. General anesthesia with endotracheal intubation is employed. A small curvilinear incision, two to four centimeters long, is made through the skin of the anterior abdominal wall 0.5 to 1 centimeter below the lower edge of the umbilical fossa. The skin edges are retracted with two Allis clamps, then with a set of two small retractors. The subcutaneous adipose tissues are reflected to expose the linea alba.

Dissection is carried out mostly bluntly with the handle of the knife, sweeping the adipose tissues inferiorly, away from the umbilicus. The exposed deep fascia is then grasped with two Kocher clamps placed side by side transversely. The fascia is held forcibly upwards and incised transversely, for approximately 1.5 centimeters, a short distance below the aponeurotic umbilical ring. Two sutures are passed, one through each fascial edge, and tagged. The fascial sutures are held upwards and apart, and two retractors are placed laterally inside the fascial incision, creating a system of four-way retraction.

At this point, the properitoneal layer of adipose tissue can be clearly viewed in most multiparous women. However, in many patients, usually nulliparous, a distinct fascial layer is present which has to be incised to expose the properitoneal adipose layer.

Blunt dissection of the adipose tissue followed by thrusting a small hemostat against the peritoneum is usually sufficient to create an opening in the peritoneal cavity. Occasionally, however, the peritoneaum has to be picked up and incised because of increased tensile strength.

A clear, adequate opening in the peritoneum, confirmed by viewing the small bowel and/or the omentum, is a useful step in the procedure. The peritoneal opening should be over one centimeter in diameter. The cannula 10 is then readied by fixing the sleeve 30 in one of the three predetermined positions (with ring 40 engaging either groove 30, 31 or 32) depending upon the thickness of the abdominal wall.

One edge of the peritoneum is held with a small hemostat to guide the cannula 10 carrying the blunt obturator 20 as it is inserted through the opening into the peritoneal cavity. The hemostat is then removed, allowing the peritoneal defect to slide freely downwards, as the cannula is placed through the abdominal wall in an obliquely slanted position. Alternatively, two small retractors may be placed inside the peritoneal defect and the cannula 10 inserted through the opening between the retractors. If the cannula is not guided in its peritoneal insertion, it may slip away from the peritoneal opening into the properitoneal space.

The fascial sutures are then tied snugly, one to each hook 46, 47 carried by valve 16, to prevent the escape of gas and to hold the cannula in place. Gas is insufflated through the cannula, creating a pneumoperitoneum. The blunt obturator 20 is withdrawn midway through the insufflation to permit a more rapid flow of gas. With the establishment of an adequate pneumoperitoneum, the lighted laparoscope is introduced through the cannula. After viewing, the abdominal wall is closed in layers.

It is seen that a device has been provided which enables laparoscopy through a small laparotomy incision. The device comprises a modified atraumatic laparoscope cannula that permits prompt insufflation of the peritoneal cavity with carbon dioxide or other gas, and subsequently seals the abdominal incision, preventing the escape of gas. Further, the cannula is maintained in place with a suture.

Although an illustrative embodiment of the invention has been shown and described, it is to be understood that various modifications and substitutions may be made by those skilled in the art without departing from the novel spirit and scope of the present invention.

Claims

What is claimed is:

1. A laparoscope cannula for use with a peritoneal cavity which comprises: a proximal shaft portion forming the inlet to receive a blunt obturator and a laparoscope; a distal shaft portion for insertion into the abdominal cavity of a patient; gas valve means coupling said proximal shaft portion and said distal shaft portion; a generally truncated cone-shaped sleeve positioned on said distal shaft portion, with the base of the cone facing toward said proximal shaft portion; and means for providing adjustable positioning of said sleeve along said distal shaft portion whereby selectively variable length protrusion segments may be provided, and further including rigid means carried by said cannula for receiving a suture, to maintain the cannula in place with respect to the patient's abdomen.

2. A laparoscope cannula as described in claim 7, wherein said adjustable positioning means comprises means for enabling a snug, manually adjustable frictional fit between said sleeve and said distal shaft portion.

3. A laparoscope cannula as described in claim 2, wherein said distal shaft portion defines a plurality of grooves about its circumference and said sleeve carries means which hug the surface of said distal shaft portion and which enter each of said grooves when aligned therewith.

4. A laparoscope cannula as described in claim 1, wherein said suture-receiving means comprises a pair of hooks located adjacent said gas valve means.

5. A laparoscope cannula for use with a peritoneal cavity which comprises: a proximal shaft portion forming the inlet to receive a blunt obturator and a laparoscope; a distal shaft portion for insertion into the abdominal cavity of a patient; gas valve means coupling said proximal shaft portion and said distal shaft portion; rigid suture-receiving means carried by said cannula to maintain the cannula in place with respect to the patient's abdomen; a generally truncated cone-shaped sleeve positioned on said distal shaft portion, with the base of the cone facing toward said proximal shaft portion, said distal shaft portion defining a plurality of grooves about its circumference and said sleeve carrying means which hug the surface of said distal shaft portion and which enter each of said grooves when aligned therewith.