Question

2011 ld and passed quickly and w Il is very that instruments smoothly. REF DEVIEW QUESTIONS C 1. What is the ratio of the abdon 2. Discuss uteri e abdominal prep in combine uss uterine distention solution le for performing the perineal prep ahead op in combined access procedures? ntion solutions used for high-frequency De ery and monopolar surgery. What is the ratie o nonelectrolytic versus electrolytic solutions in bipolar surgery and mo nale for using nonelectro each case? ne distention fluid have to be closely 1 3. Why does monitored during hysteroscopy? List the risks of the lithotomy position and the precam needed to prevent patient injury. Review the imaging system components for laparoscopy found in Chapter 23. List the components and their basic uses. 6. What is the risk of allowing an ovarian cyst to rupture into the pelvic cavity during surgery?! 7. Babcock clamps usually are required for any surgery of the fallopian tubes. Why wouldn't a Kocher clamp be used instead? M

Answer 1

1. the perineal prep is performed first, the rational for this is to prevent possible contamination of the abdomen from splashed droplet during the perineal prep

2. uterine distention solutions used high frequency bipolar surgery and monopolar surgery

Biological tissue contains a more or less high concentration of electrolytes, making it sufficiently conductive to be treated electrosurgically. The thermal effect of high-frequency current is used for separating (cutting) and coagulating tissue (desiccation of tissue). The high-frequency currents must be used on the patient since low-frequency currents can stimulate nerve and muscle cells in the currents flow due to electrochemical processes (electrolysis). These effects are small enough to be disregarded with frequencies above 100 kHz.

Monopolar or bipolar current system can be adopted

Monopolar resectoscope

Conventional hysteroscopic surgery uses a monopolar electrocautery system in which the current passes from the active electrode through the patient’s body towards the return plate. The distension media used is glycine 1.5% sorbitol–mannitol (non-electrolyte irrigation fluid). The monopolar resectoscope is connected to monopolar electrosurgery generator of high frequency and automatically controlled by an acoustic alarm system. In a monopolar system, the electrons flows from a electrosurgery generator to active electrode (electrode of the loop). From the electrode, the current flow is transmitted to tissue then to the plate (neutral electrode) and returns to generator. This system is potentially dangerous since the electrons flows through the body, outside the surgeon visual control, before it can return to the generator. The new generators, however, decreased the incidence of electric damage. In these generators, the cut current flow is automatically regulated based on tissue resistance. The unipolar loop can be used as coagulation, cut and combined (coag–cut) current. The coagulation current flow is characterised by intermittent current flow periods, which cause cellular dehydration, resulting in tissue haemostasis. The non-modulated cut flow is a continuous flow, with high intracellular temperature, causing cellular explosion. Non-modulated flow can be used also for coagulation and it should be preferred because the voltage is lower and continuous

Bipolar resectoscope

In bipolar electrosurgery, the current flow through the tissue is restricted to the area between the two electrode’s loops that are under visual control of the surgeon (Figs. 1 and 2). In this case, saline solution can be used as distension media because it has no risk of current dispersion. The generator produces a high initial voltage spike that establishes a voltage gradient in a gap between the bipolar electrodes. When the activated bipolar electrode is not in contact with the tissue, the electrolyte solution in the uterus dissipates it. When the loop is sufficiently close to tissue, the high bipolar voltage spike arc between the electrodes converts the conductive sodium chloride solution into a non-equilibrium vapour layer or “plasma effect” containing energy-charged sodium particles. Once formed, this plasma effect can be maintained at lower voltages (100–350 root mean square voltage) . With tissue contact, there is disintegration of tissue via molecular dissociation. Energetic species of the charged ions from the plasma effect result in disruption of carbon–carbon and carbon–nitrogen bonds. There is also electron impact dissociation of water molecules into exited fragments of H+ and OH− ions. The bottom line is rupture of cell membranes which translates into visible cutting. Clinically, there is a precise tissue effect with minimal collateral damage, as the charged ions have an estimated penetration depth in tissue of only 50 to 100 μm (0.5–1 mm) The depth of coagulation is determined principally by the electrode configuration and by the system design, as well as by the technique used by the operator

3.A common early complication of this technique is the vault haematoma, while urinary tract and bowel injuries and peri-operative bleeding are the most severe injuries occurring during hysterectomy

4.Peripheral nerve injury has been reported after surgery in the lithotomy position. Injury to the common peroneal nerve appears to be the most common nerve injured. Symptoms include motor weakness in ankle extension, ankle eversion, and foot dorsiflexion

the lower portion of the table is raided or replaced to align with the rest of the O.R. table. The patient’s legs are removed from the stirrups simultaneously, extended fully to prevent abduction of the hips and slowly lowered onto the table and the table strap, like the VeriClean Patient Safety Strap, is applied for safety