What would you do if the following situations occurred during a laparoscopic operation?
(a) The field turns pink or yellow.
1. Has a white balance been carried out?
2. Is the light cable connected properly?
3. Low voltage can sometimes alter the colour.
4. Bile or blood spillage may turn the field pink or yellow .
(b) Sudden black out.
1. Has the light source bulb fused? Switch of light source & turn to backup bulb.
2. Has the camera or monitor cable become disconnected?
3. Has the camera fuse blown due to fluctuation in voltage.
4. Is the laparoscope touching any object completely?
(c) Poor definition of picture.
1. Is the lens dirty; clean with warm water?
2. has the camera been white balanced and focussed properly?
3. Is there too much light absorption from blood in the operative field?
What action would you take to control intra abdominal bleeding from a trocar site?
(a) For immediate control.
1. Apply pressure either from outside or use a pledget from within under vision.
2. A Foley catheter can be inserted, the balloon inflated & pulled up to act as a tamponade
3. A purse string suture can be taken around the trocar incision and tightened
4. If necessary a clamp can be applied to the port site until the bleeding is controlled
(b) For more permanent control.
1. The vessel can be sutured from within under vision or controlled with diathermy, or a full thickness bite can be taken externally at the region of the bleeding vessel.
2. The incision can be extended and the vessel found and then ligated.
What action would you take if trocar injury to a large vessel occurs?
1. Leave the trocar in place, recuscitate the patient ASAP as you undertake a prompt laparotomy and repair the vessel. Have a vascular clamp handy. Do not panic.
2. Dent delay whilst you seek the help of a vascular surgeon. The patient will die!
What would you do following a sudden collapse of the patient during a procedure? Name 5 possible causes.
Possible causes for the collapse could include:-
- Venous bleeding and loss of circulatory volume
- Vasovagal shock due to peritoneal irritation
- CO2 embolism either by direct entry of gas into vessel or through absorption.
- Hypercarbia due to systemic CO2 absorption result in respiratory acidosis, pulmonary hypertension leading to cardiac dysrhythmia
- Arrhythmias – AV dissociation, junctional rhythm, sinus bradycardia and asystole due to vagal response to peritoneal stretching.
Stop insufflation and deflate the abdomen, the patient should be kept head down and right side up (steep left lateral Trendelenburg position) and 100% O2 administered. If you suspect blood loss (blood will well up in the ports convert to an open procedure. Blood gas levels should be corrected accordingly. Gas in the right ventricle should be removed with a central venous catheter. For arrhythmias give Atropine & the appropriate anti arrhythmic Dc cardioversion etc.
What pressure setting on the Insufflator would you select at the start of a diagnostic laparoscopy in an adult healthy patient?
If general anaesthesia is employed set the starting flow rate at 1/L, pressure 12 mmHg and volume- 2L.
During diagnostic laparoscopy under local anaesthesia insufflation is begun at a flow rate of 1L/min. Initial low pressure- 2-3mmHg and volume not exceeding 2L.
(6).What would you do?
(a) High pressure is registered in the VN before the needle has been placed in the body.
The verres needle may be blocked, the gas tap not be opened or the tubing kinked. Flush the verres needle with saline. A faulty needle should be changed.
(b) High pressures (10 or 15 mm Hg) are obtained during insufflation at 1L/min.
The needle may be in the wrong plane ie., not in the peritoneal cavity.
Gas tap or needle may be partially blocked
Withdraw the needle and reinsert.
What would you do if after insufflation and on insertion of the telescope
(a) You saw gas in the greater omentum?
Gas in the grater omentum suggests that either the Verres needle or the trocar has entered it and insufflated gas into it. There is an increased risk of systemic absorption of CO2 resulting in embolism. The necessary precautions to prevent this should be taken.
(b) Fat is seen and there is no crepitance in the abdominal wall.
The laparoscope is probably in the omentum and should be withdrawn. Check for possible injury of the omental vessels.
What action would you take when?
(a) You are unable to advance a trocar into abdomen.
If the trocar is a disposable one, confirm whether the blade tip is charged and re- introduce. Alternatively, the tip may get discharged half way. The trocar should be removed, recharged and inserted again. If it is a reusable trocar the tip may be blunt in which case it would be better to use a different sharp trocar.
(b) The tip of the obturator is seen entering the abdominal cavity during insertion of a secondary trocar.
The skin incision may be small so the trocar has to be removed, the incision should be extended and the trocar should be re- inserted.
List the safety mechanisms of different types of trocars?
- Blunt (Hasson) trocar - blunt with insertion under direct vision. This type of trocar works on the safety of direct vision.
- Some disposable trocar have a sharp blade with a spring loaded safety shield which cover the blade tip once the peritoneal cavity is entered. This spring loaded spring mechanism reduces the risk of injury to the underlying viscera by the blade tip.
- Other disposable trocars require charging before insertion and when the tip enters the peritoneal cavity the blade tip retracts inside.
- Reusable trocars have triangular and conical tips. The triangular tips are sharper and tend to cause more vascular injury, the adequate force and fine hand movement is required for its safe use.
- Some disposable trocars have a screw shaped cannula, which has to be inserted like a screw, which enables the surgeon to have more control over the force with which he inserts the trocar. These have an additional advantage of not slipping out during the procedure.
- Non bladed obturators are used in some trocars for careful insertion where the problem of charging the blade tip and its patency does not arise.
- Visiport is a mechanism in which the telescope is inserted into the cannula and the gun is fired through the abdominal wall visualising each layer until the peritoneal cavity is reached. The trocars are thus inserted under vision layer by layer.
- Radially dilating trocars are also available. It has the advantage of entry through a very small incision and then incision can be dilated with the serial dilator.
- Ultrasonically activated trocar system is used in some high risk patients. It consists of an ultrasonic generator and a transducer attached to the trocar spike. The sharp pyramidal tip is activated with a frequency of 23.5 KHz and amplitude of 150 Micro m. The trocar fits a 5 mm plastic sheath that is introduced inside a 10mm dilator whose tip is conical.
List the factors that increase the risk of complications with a Verres needle.
Faulty needle – dysfunctional spring tip.
Wrong method of insertion.
Uncontrolled forceful insertion of needle.
Wrong angle of insertion i.e. directing straight down instead of towards the pelvic cavity.
Excessive force from shoulder rather than wrist while inserting.
Previous abdominal surgery and scarred abdomen.
Thin scaphoid individual: risk of deep entry.
Spinal deformities kypho-scoliosis.