Surgical Instruments

Telescopes are used to visualise inside the abdomen during laparoscopy or cystoscopy. The size ranges from 0.8 mm (needle scope) to 15 mm diameter. The brightness of the image reduces with decreasing size of the scope. The angle of view can be a straight-on view at 0° or angled at 0°/30°/45°/70°/120°. Zero-degree telescopes provide a field of view of only 76°. A 30° telescope provides a total field of view of 152°. The 30° forward oblique angle permits far greater latitude for viewing areas under difficult anatomical conditions, has an unobstructed view from a distance and provides more space for instrument manoeuvrability.

There are two lens system designs:

• conventional thin lens system
• Hopkins rod–lens system.

The thin lens system, which consists of a series of objective lenses to transport the image down the laparoscope, is used less commonly. The Hopkins lens system, which consists of a series of quartz-rod lenses, carries the image through the length of the scope to the eyepiece, providing good resolution and better depth perception. As there is more glass than air, there is improved light transmission.

The most commonly used telescope is the Hopkins forward-oblique telescope (30°), which has a diameter of 10 mm, a length of 33 cm and is autoclavable. The scopes that are available can be rigid, flexible or semiflexible.

This is a narrow tube made of non-toxic, medical grade polyvinyl chloride (PVC) or polyurethane. The distal end is coned with steel balls sealed into the tube to facilitate easy insertion. Four lateral eyes along the distal end provide efficient drainage of secretions/fluids. The tubes are marked at 50, 60 and 70 cm from the distal end for accurate placement into the abdomen. The radio-opaque line provided throughout the tube helps radiographic visualisation. The proximal end is provided with a universal funnel connector for easy extension and allows a drain or feeding bag to be connected. Sizes available are 6–18F for adults and 10–14F for children. Ryles tubes are available in packs that have been pre-sterilised with ethylene oxide. They are also available individually in peelable pouch packs.

Nasogastric tubes are used for:

• aspiration in cases of intestinal obstruction and pyloric stenosis
• diagnosis of gastrointestinal haemorrhages and acute gastric dilatation
• enteral feeding and administration of drugs.

To insert a nasogastric tube, position the patient in the lateral position so as not to compress the oesophagus; alternatively, flex the neck in the supine position with pressure on the arytenoid cartilage. Different sizes of Ryles tubes should be kept ready, along with 2% lidocaine gel, sterile gloves and syringes. The nasogastric tube should be well lubricated and passed through one of the nostrils. Once it reaches the throat, the patient should be asked to swallow. The tube then easily enters the oesophagus and stomach. To check the patency of a Ryles tube, push 5–10 mL of air through it using a syringe. Auscultate with a stethoscope on the epigastric area below the xiphisternum or check radiographically to confirm the position. Fix the Ryles tube to the ala with tape.

Complications of nasogastric tubes include discomfort to the patient because of the tube, nasal bleed/epistaxis, damage to the nasal and oesophageal mucosa and gastric reflux, which may cause aspiration.

Scissors are used for many purposes during a surgical procedure. They come in many different shapes and degrees of sharpness. The purpose of the scissors determines the type needed.

Scissors used for cutting tissue or materials, such as cutting bandages (bandage scissors), cutting sutures, cutting tissue and dissection scissors, have two sharp blades that are screwed together at the centre and are used to cut together.

Surgical scissors, suture scissors, nurse’s scissors:

1. Multipurpose cutting and dissecting scissors with sharp/blunt, sharp/sharp or blunt/blunt tip configurations; straight or curved; and varying sharpness and lengths. These are used for general cutting of sutures, gauze and other materials. Sharp blades are used to cut tougher tissue and are frequently used for dissection; blunt blades are used for cutting materials such as tubing or gauze.
2. Operating, or surgical, scissors come in different sizes and are used to cut soft tissue. The blades can be straight or curved and the tips can be blunt or pointed. The type of operation will determine the shape of the cutting blade.
3. Dissecting scissors are used to separate and differentiate tissues; hence, they are more precise than operating scissors. Iris scissors are small and designed for excising lesions on, or portions of, the iris of the eye.

All types of scissors are sterilised at the same time to avoid loss of sharpness; this is done by autoclaving, plasma sterilisation or chemical sterilisation.

There are two types of operating scissors:

1. Mayo straight scissors (dissecting scissors, suture scissors, heavy tissue scissors): A versatile instrument for multiple procedures and settings; the straight version is primarily used for cutting surface tissue or sutures, but both curved and straight versions are used interchangeably depending on the procedure and the physician’s preference. These have a standard bevelled blade, a variety of lengths and special features, such as blunt tips.

Mayo curved scissors: These scissors are used in multiple procedures and settings and are versatile; the curved versions are commonly used for cutting or dissecting deep or dense tissue.

A right-angle forceps, or Mixter forceps, is an instrument with a ratchet with finger rings and a pair of right-angled jaws. The jaws are fully serrated, which enhances the grip on tissue and thread while minimising clamping injury; they are available in multiple lengths. They are most frequently used for working in obscured surgical sites to ensure access to hard-to-reach cavities in multiple fields. They are used to grasp tissues, mobilise and clamp blood vessels or similar tubular structures (cystic duct/artery, Fallopian tubes, appendix or cord structures in the inguinal canal) and perform blunt dissection to divide soft layers of tissue. They are sterilised by autoclaving.

A sponge-holding forceps is a long, straight instrument with round, fenestrated ends. It has a load arm, an effort arm and a box joint. The load arm has a rounded fenestrated tip with transverse serration on the inner surface only at the tip. The fenestration and transverse serration help to give a firm grip on the sponge and to prevent the sponge from being squeezed dry. The effort arm has a finger rest with a three-in-three ratchet. The ratchet lock on the handles allows a secure grip on the swab that is being held. The length ensures that antiseptics can be applied to the part being prepared for surgery from a distance so that the surgeon’s hand is not contaminated with bacteria from the patient’s skin and vice versa. They are commonly used for painting parts prior to surgical incision, as a deep cavity dissector, as a deep cavity haemostat (rarely) and in various gynaecological and obstetric procedures.

A sinus forceps is slender, long and straight, with slightly expanded smooth tips but no ratchet catch on the handles. It has a load arm, an effort arm, a box joint and no catch. The load arm to effort arm ratio is 1:1, increasing mobility at the cost of power and precision. The load arm has a bulbous end that is blunt with serration only on the inner side of the tip. They are used for abscess drainage by Hilton’s method. (It is called a sinus forceps because it converts a closed abscess into an open sinus.) Other uses include packing of an abscess cavity, probing a sinus for a foreign body in a granuloma and as a dressing forceps on the ward.

This tube is extensively used for controlling variceal bleeding as a temporary treatment or as definitive management prior to endoscopy management.

The tube is made of latex or India rubber and essentially has three channels. The main wide channel is used for gastric lavage. It has a closed tip with multiple openings on the side of the tip. The second channel runs through the main channel, hugging the wall and running parallel to the main channel. It opens distally into a rounded balloon that is placed just proximal to the tip. The proximal end of the second channel opens into a valve adjoining the main channel. Inflating through this valve, the balloon, which is also called a gastric balloon, inflates and, when hitched, compresses the varices against the cardia on its undersurface, temporarily arresting the variceal bleeding. The third channel also hugs the main channel on the opposite side and opens into an oesophageal balloon, which, when inflated, inflates the longitudinal balloon and is meant for tamponade on varices in the oesophagus. The valve to inflate the longitudinal balloon is at the same level as the gastric valve. The tube is calibrated, showing the gastric balloon level and the oesophageal balloon level. The main channel is long enough to reach the pylorus. This tube is only used to arrest bleeding varices in portal hypertension. The main channel is used for gastric washing and to clear blood, which if absorbed distally can lead to hepatic encephalopathy. One modification of an SB tube is known as a Linton’s modification. This modified tube has no oesophageal balloon and the gastric balloon has a capacity of 500 mL; it is used for gastric tamponade only. Another modification is Minnesota’s modification; this has four lumens, three of which are as in an SB tube and the fourth one opens proximal to the oesophageal balloon for aspiration of the oesophagus and so that the saliva is aspirated. Any of these modifications of the balloons are used in a collapsed state and are passed either through the nose or more commonly through the mouth after lubricating well. Traction is given on the tubing over a cricket helmet for pressure tamponade.

It is important to note that, because of recent developments in emergency medical management and endoscopic and radiological techniques in the management of emergency variceal bleeds, the use of these tubes has reduced significantly.

A proctoscope is a hollow, tube-like, metal/plastic instrument for visualisation of the anal canal and lower rectum. Both disposable (plastic) and non-disposable (steel) proctoscopes are available and they can be self-illuminating. They are approximately 10–15 cm long. They consist of a long cylindrical tube that is slightly tapered towards the distal end with a handle and obturator that fits snugly inside to avoid injury while introducing the proctoscope into the anal canal. The proctoscope with the obturator in situ should be well lubricated and introduced into the anal canal with the patient in the Sims position. It is important to remember that the anal canal is directed upwards and forwards towards the umbilicus. After the proctoscope is fully introduced, the obturator is withdrawn with the scope inside. It can be used to look for haemorrhoids, the internal opening on a fistula track, polyps and ulcerations. It can also be used to perform small procedures such as injection therapy for haemorrhoids, localisation of the internal opening of a fistula by injection of methylene blue through the external opening and diagnosing inflammatory disease and more serious conditions such as lower rectal and anal canal carcinoma.

A Maryland dissector is commonly used for dissection during laparoscopic surgery. They can be reusable or single use. They have a gently curved tip that is around 30 cm long. There is a rotator to help rotate the tip, a finger grip and a pole for a cautery attachment. This instrument is used for dissection, holding tissue, haemostasis and looping structures such as vessels and cystic ducts. Its tip can be at a right angle or it can have a bipolar rotating tip.

These are called ports as they are portals for entry into the abdominal cavity. They can be of various sizes, such as 5 mm, 6 mm, 10 mm and 12 mm. All trocars have two parts: one is the cannula and the other is the trocar. The tips of the trocar can be conical, blunt or pyramidal in shape. There is an eye at the tip of the trocar for gas to escape; a hiss is used to confirm that the system is inside the abdominal cavity. The cannula has two parts: the shaft and the valve. The valves can be either magnetic or flap valves; this allows unidirectional insertion of the instruments and prevents any leakage of gas after the instruments have been withdrawn. On the top there is an outer washer that does not allow gas to leak from the side of the instrument when operating. The cannula has a Luer lock for attaching gas tubing and to control the flow of gas through the cannula across the abdominal cavity. The trocar is inserted after making an incision on the skin into the abdominal wall; supporting the trocar on the thenar eminence, the middle finger is wrapped around the Luer lock with the index finger pointing towards the sharp end. The trocar is introduced with a screw-like action so that the muscles are split as the trocar and cannula enter the abdominal cavity.

The trocar–cannula system can be disposable, with an in-built knife through which a 0° scope can be introduced. This can be used to gain entry into the abdominal cavity under normal vision, especially in bariatric patients. Five-millimetre ports are generally used for instrumentation, 6-mm ports for instruments as well as for harmonic scalpels and clip applicators, 10-mm ports are used for telescopes and wider instruments and 12-mm ports are used for endo-stapler introduction and for the introduction of mesh into the peritoneal cavity in hernia repair.

Needle holders are made of stainless steel and are used to hold a suturing needle during a surgical procedure. They have jaws, a box joint, a shank, a ratchet and rings to hold the needle. Needle holders come in various sizes, ranging from 15 to 30 cm. The size of the tip of the needle holder is determined by the size of the needle. The needle holder should be fine enough to hold a hair on the back of the hand. In order to maintain a firm grip on the needle, the jaw has either a textured pattern, directly etched on the stainless steel, or a tungsten carbide tip. The tip gives a firm grip on the needle and is slower to wear out than steel. Tungsten carbide needle holders are identified by a golden ratchet and rings.

A Cambia Bozeman needle holder is commonly used in gynaecological surgeries. The shank of the needle holder is slightly curved to give good visibility when used in the uterine cavity. A Castroviejo needle holder is available with a curved- or straight-tip palm-locking action; this is designed for thinner suture material such as 5-0, 6-0 or 7-0.

This vascular clamp has a 60° angle with one or two serrations or grooves internally. It is made of stainless steel and is used for grasping or fixation of vessels for vascular procedures.

Bulldog clamps come in a variety of angles for surgical applications. Most bulldog clamps open when the handles are squeezed; conversely, they shut when the pressure is released. They have jaws that are straight or curved, a shaft or handle, a box joint with a weak spring action so as not to crush the tissue and are available with grasping jaws in sizes ranging from 2.5 to 5 cm. They are used as a fastening device to hold or secure objects tightly together to prevent movement or separation by application of an inward force. They are used for stopping or controlling blood flow to a particular organ of interest. They are also used in cardiothoracic surgery and in open surgery when blood vessels are being handled.

This vascular clamp consists of a ring finger handle, a ratchet lock mechanism and harmless teeth that are arranged in one or two serrations, causing less trauma to the encompassing structures. The slightly angled U-shaped jaws provide enough grip on the vessels without injuring or crushing the intima and occluding the blood flow. They come in various sizes from 15 to 23 cm depending on the size of the vessel. They are made of stainless steel and are used for partial or total occlusion of blood vessels when performing vascular procedures.

Intestinal occlusion clamps are made of stainless steel, the jaws are long and flexible with fine longitudinal serrations and they have a ratchet-type locking mechanism to provide stable pressure for clamping. The instrument is slightly concave so the jaws only meet at the extreme end of the locking mechanism. The clamp occludes the lumen of the intestine so that there is no spillage of content; simultaneously, the vessels are clamped so as to keep the operating field dry. They are used for temporary occlusion of the bowel during resection and anastomosis. They can be used either alone on the side of the bowel to be preserved or with an intestinal crushing clamp on the non-viable side. They come in various sizes with a jaw length of 8.25–16.5 cm depending on the size of the bowel to be occluded.

This is made of stainless steel or plastic. It has a long shaft with a wide lumen to avoid clogging, a bulbous tip for patient comfort, a control vent for controlling the rate of suction and a grooved handle for a proper grip. The long length and two angles are for accessing the surgical site to keep the area dry without obstructing the surgeon’s vision. The plastic version helps in visualisation of the suction fluid.

A Doyen retractor is a long, stout instrument with a curved blade. It is used to retract the cut edges of the abdominal wall during abdominal operations by laparotomy. It can also be used for retraction of the lateral sides of any vertical incisions. It provides wide but superficial retraction.

This is a self-retaining catheter made from latex rubber. It has two channels: a large channel for drainage of urine and another smaller channel for inflating the subterminal balloon with sterile normal saline or distilled water to make it self-retaining. The capacity of the balloon is 15–50 mL. It has a solid tip and two subterminal side openings for drainage of urine. The proximal end is bifid. The larger opening is connected to the reservoir bag. The smaller one leads to the channel connected to the balloon. There is a valve in it that prevents the saline or distilled water from escaping. Special silicone-coated catheters are also available. They are better tolerated by patients and can be left in the bladder for 3 weeks, while the standard type has to be changed every week. The size of the catheter is written on the side of the catheter at the proximal end using a colour code. A Foley catheter is used for urine drainage, monitoring of urine output in patients with shock, drainage of urine after bladder or urethral surgeries and to give a bladder wash.

This is an instrument that has an identical configuration to a haemostat with a few changes. With a standard haemostat, if used to clamp a thick pedicle containing a bleeding vessel, there is a significant chance that the tissue in the pedicle along with the bleeding vessel may slip from the clamp at the tip of the load arm. Thus, a haemostat is used only when the bleeding vessel can be seen clearly or is dissected free from the surrounding tissues and the isolated vessel is clamped. There are situations, such as clamping the uterine arteries in the pelvis during hysterectomy, when the isolation of a vessel with a haemostat is not feasible. Hence, Kocher modified the haemostat by adding two-in-one teeth at the apex of the load arm on the inner surface. This helps to grip tissue within the load arm, preventing it from slipping from the load arm and transfixing it easily. Kocher pedicle clamps are used principally to clamp pedicles and not isolated bleeding vessels. They are available in small, medium and large sizes. Both straight and curved varieties are also available.

This is a double-ended, spoon-shaped instrument. One end is similar to a curette and is used for desloughing the contents of an abscess cavity, sinus, fistula or ulcers. The other end is sharp and is used to scoop out cancellous bone to collect tissue. The centre of the instrument is broader and is ribbed to give a good grip on the instrument while using it. It is used to scoop out the floor of an abscess, to break up loculi, to scoop out the floor of an ulcer and infected granulation tissue and to scoop out all the infected tissue in infected wounds. The scoop is also used for scraping healthy granulation tissue prior to skin grafting. It can be used to place antibiotic powder in an abscess cavity after scraping and to scoop blind sinuses.