BASIC OF SURGICAL TECHNOLOGIES
Renal changes y Decrease in renal plasma flow, glomerular filtration rate, urine output
Hypercoaguable state y Pneumoperitonum and reverse trendelenburg position that is used both increase venous stasis in lower limbs. Patients of old age, obesity, prolonged surgery are at increased risk
y A Caprini score of 2 is given to all laparoscopic surgeries > 45 minutes and mechanical prophylaxis is advised in them Stress and endocrine
responses y Cortisol elevation is more in laparoscopy than in open surgeries y However, stress induced changes such as cytokine elevation,
leucocytosis, hyperglycemia, immune system changes are less in laparoscopy compared to open surgery.
Advantages of laparoscopy are as follows:
Patient
y Rapid postoperative recovery and early return to work
y No scar and therefore no scar related complications such as pain, incisional hernia, wound infection, seromas, hematoma, dehiscence or scar tenderness
y Aesthetic value due to no scar which also gives psychological advantage.
Operation
y Less need of blood transfusion during surgery due to less blood loss y Less need of analgesics and antibiotics
y Less chances of adhesion formation and visceral exposure therefore, less chances of infection transmission.
Hospital
y Rapid turnover of patients so more economical gain
y Shorter hospital stay and less complications improve the hospital reviews
y Laparoscopy is more educational than open surgery as all can view the television and learn. So it is a better teaching tool for the hospitals.
Disadvantages of laparoscopy
y Loss of natural hand eye coordination as the camera (eyes of laparoscope) is in the hands of the assistant
y Loss of 3 dimensional visual perception—the perception of depth is impaired. However, this is being taken care of by 3-D systems that are now available
y As the instruments have fixed motion range at trocar points, the range of motion is limited y There is loss of tactile feedback as the surgeon cannot feel the structures directly y Exaggeration of physiological tremors and compromised ergonomics
y This leads to increased surgeon and assistant fatigue
y Has longer learning curve. Due to loss of wrist like motion, suturing and knot-tying are particularly difficult
y Procedure itself is more costly and may take longer time than open procedure. This, however, can be taken care of by decrease in the postoperative costs.
Contd...
Complications of laparoscopy Injuries
Verres needle injuries y Usually not significant because of the small diameter of Verres needle
y Can be visceral or vascular injury which is taken care of after trocar placement
Trocar injuries y Inferior epigastric artery bleed
y Small intestine or large intestine perforation y Solid visceral injury
y Urinary bladder injury
y Major mesenteric or retroperitoneal vessel bleed Instruments related injury y Injury due to insulation failure or capacitative coupling
(Described in question on electrocautery) can lead to visceral burns and delayed perforation peritonitis (after 4 to 5 days) or cutaneous burns.
y Injuries by misidentification (e.g. common bile duct injury during laparoscopic cholecystectomy) y Injuries during manipulation and retraction—bowel
injuries, liver injuries, etc.
y Injuries during dissection and hemostasis to any organ y Tears and splits in organ while retrieval or handling
(e.g. gallbladder perforation, spleen rupture, etc.)
Pneumoperitoneum
y Cardiac arrhythmias—bradycardia, ectopics, asystole y Gas embolism
y Pneumothorax, pneumomediastinum
y Hypothermia and peritoneal trauma due to cold CO2 gas exposed during insufflations.
Postoperative complications
y Though the risk is less, there is still chance of port site infection and abscess y Delayed risk of port site hernia
y Port site metastasis if the laparoscopy was performed in malignancy cases y Deep vein thrombosis of lower limb
y Basal atelectasis and pneumonia
y Shoulder tip pain due to CO2 causing phrenic nerve irritation Contraindications of laparoscopy
Though there are no definite absolute contraindications or definite guidelines on these issues, the following are routinely considered as contraindications to laparoscopic surgeries and are listed below:
Absolute
y Third trimester of pregnancy—lower abdominal and pelvic surgeries by laparoscopy are especially not to be done
y Child C liver disease or liver disease with gross ascites
y Patients with hemorrhagic shock and hemodynamic instability
y Patients with severe cardiopulmonary compromise such as severe COPD or severe congestive heart failure.
Relative
y Locally invasive malignancies—though laparoscopy is being used in early stage malignancies, locally invasive malignancies are still considered contraindication to laparoscopy because of the risks of cancer dissemination and/or port site metastasis.
Also malignancies such as mucinous or signet cell adenocarcinomas are friable, prone to disseminate and implant and are therefore considered relative contraindication y Intraperitoneal mesh placed in the area of surgery
y Multiple previous intraperitoneal surgeries in the same area y Inexperience
y Uncorrected coagulopathy is a relative contraindication
y Patients with acute brain injury and ventriculoperitoneal shunts are also relative contraindication.
Q32. Enumerate the indications of diagnostic laparoscopy
Ans. The broad categories and indications of diagnostic laparoscopy are as follows:
To ascertain the cause of
abdominal pain y Peritonitis
y Gastrointestinal hemorrhage of unexplained etiology y Intusussception
y Postoperative adhesions y Mesenteric ischemia y Gynecologic causes
y Cases of small bowel obstruction In blunt or penetrating trauma y To rule out diaphragmatic injuries
y Exclude peritoneal breach in penetrating trauma In abdominal or pelvic tumors y Confirmation of disease (Peritoneal carcinomatosis)
y Staging laparoscopy In Infectious causes y Acalculous cholecystitis
y Ruptured liver abscess
Q33. Write a note on NOTES (Natural orifice transluminal endosurgery).
Ans.
y Natural orifice transluminal endoscopic surgery (NOTES) is an emerging experimental alternative to conventional surgery that eliminates abdominal incisions and incision- related complications by combining endoscopic and laparoscopic techniques to diagnose and treat abdominal pathology
y The SAGES (Society of American Gastrointestinal Endoscopic Surgeons) and ASGE (American Society of Gastrointestinal Endoscopy) came together in 2005 to establish NOSCAR (natural orifice surgery consortium for assessment and research). They gave the term NOTES
y In NOTES, the operation is performed in the peritoneal cavity having gained access through a natural orifice rather than a direct transcutaneous access
y In hybrid NOTES, the operation NOTES is combined with some part of operation being performed through direct transcutaneous access.
Technique Peritoneal access y Should be safe y Minimal tissue injury y Good exposure
y Ability to manipulate instruments and at the same time have a good seal around the instrument.
Options
y PEG approach (transoral and through stomach) y Transvaginal
y Transrectal.
Closure
y Apparatus for closure are available such as T tags, star tags, basket tags, etc.
y This is an area of surgery still under research.
Procedures contemplated y Tubal ligation y Appendicectomy y Splenectomy y Oophorectomy
y Cholecystectomy—first transvaginal cholecystectomy was performed by Marescaux and Bessler (2007).
Challenges
y Intraperitoneal complications – Early or delayed presentation
– Can lead to infection, bleeding, anastomotic leak, closure site dehiscence – Vascular injury during access procedure
– Damage to viscera – Adhesion formation – Post NOTES dyspareunia
y Dexterity and technological challenges
– Requisition of a multichannel NOTES platform that can bend in more than 2 axes – Present available instruments are not robust enough to provide the much required
properties of triangulation, retraction and dissection
– Spatial orientation of surgeons to endoscopic views and of endoscopists to the laparoscopic view requires training
– Instruments currently available are not capable of providing good suturing in NOTES whether for access site closure or intraoperative suturing for hemostasis control or anastomosis.
y Training, education and availability of the equipment is yet another problem.
Benefits of NOTES
y Absence of incisional complications including pain, hernias and external wound infections
y Hopefully there would be fewer adhesions y A decreased need for anesthesia
y A shorter hospital stay
Q34. Enumerate the uses of therapeutic embolisation.
Ans. The development of techniques for inserting a catheter percutaneously and manoeuvring it into almost any artery with safety and confidence is one of the major advances in medicine.
At first the main aim was to obtain better angiograms, but now arterial catheterisation has acquired increasing therapeutic value. In addition to allowing regional infusions of drugs and mechanical dilatation of stenoses in arteries, catheters may now be the route by which the radiologist deliberately introduces emboli into vessels feeding tumours, vascular abnormalities or sites of bleeding. This approach is called therapeutic embolization.
Indications
y Vascular malformations: Occlusion of congenital or acquired aneurysms (cerebral, visceral, extremities), pseudoaneurysms, vascular malformations or other vascular abnormalities that have potential to cause adverse health effects
y Nontraumatic hemorrhage: Treatment of acute or recurrent hemorrhage (e.g.
hemoptysis, gastrointestinal bleeding, postpartum and iatrogenic hemorrhage and hemorrhagic neoplasms)
y Trauma: For control of dramatic hemorrhage, for example, related to splenic laceration or pelvic fractures
y Uterine artery embolization: Devascularization of benign uterine leiomyomas and adenomyosis for symptom alleviation or to reduce operative blood loss
y Oncologic embolization: To relieve symptoms, prevent or treat hemorrhage, reduce operative blood loss or improve survival and quality of life. For example primary and secondary hepatic malignancies, renal cell carcinoma and primary and secondary bone malignancies
y Tissue ablation: Ablation of benign neoplastic and nonneoplastic tissue that produces adverse health effects to the patient (e.g. hypersplenism, refractory renovascular hypertension, untreatable urine leak, proteinuria in end-stage kidney disease, renal angiomyolipoma, varicocele, pelvic congestion syndrome, priapism, and abdominal pregnancy).
y Flow redistribution:
– To protect normal tissue (e.g. gastroduodenal artery and right gastric artery embolization in hepatic artery chemoembolization and radioembolization or – Proximal superior gluteal artery coil embolization during particle embolization of the
anterior division of the internal iliac artery for tumor devascularization) or
– To facilitate other subsequent treatments (e.g. right portal vein embolization to induce left lobe hypertrophy before surgical resection).
y Endoleak management: Including direct sac puncture or collateral vessel embolization for endoleaks
y Regional therapy delivery: Vehicle for delivery of drugs or other agents that may include oncolytic viruses, chemotherapy, beta -emitting spheres or other agents used to treat an organ or specific target lesion
y Enterocutaneous tracts and lymphatic abnormalities: Embolizing abnormal communications between organs from cavities or organs to the skin surface, thoracic duct leaks,lymphedema.
Embolisation materials include autologous clot, gelfoam, muscle, silastic balls, silicone balloons, steel coils and cyanoacrylic glue.
Some produce permanent occlusions, some temporary.
Q35. Write a note on surgical diathermy.
Write a note on electrocautery uses in surgery.
Ans. Electrocautery uses direct current whereas electrosurgery uses alternating current Principles of thermal tissue destruction
y 60°C—coagulation necrosis
y 80°C—carbonization and shrinkage y 100°C—cell vaporization—gas and smoke y >100°C—carbon residue/Eschar formation
Current flows from electrosurgical unit to patient via active electrode and returns to unit via return electrode.
Types
y Monopolar—return electrode is through the patient (grounding plate) and therefore path of current is unpredictable
y Bipolar—current passes between electrodes and flow of current beyond surgical field is minimal. It is approved for sealing vessels up to 7 mm in diameter.
Current effects
Cutting Coagulation Fulguration
Continous wave Pulsed waveform High power
Low voltage High voltage Low current density
High frequency Low frequency
However, coagulating current can be used as cutting current by decreasing the surface area of contact between active electrode and skin and therefore increasing current density.
For example, in laparoscopy the use of monopolar electrosurgery by “L” hook shows that when the tip of L hook is used, it decreases the surface area and acts as cutting electrode while the base of L hook acts as coagulating electrode by decreasing current density with the same current flow.
Fulguration is produced when low current density and high power current by outer side of L or spatula is used at an increased distance (no touch technique) from the specific bleeding point which allows superficial tissue heating.
Special issues with laparoscopic electrosurgery Insulation failure
y Laparoscopic instruments are normally insulated up to their tip. When this gets removed, injury to adjacent viscus can occur or current can pass through metal trocar and dissipate unknowingly causing injury
y The effect of insulation failure can thus be outside of the visual field of laparoscopy and may present late.
Direct coupling
y When one conducting material touches or arcs to another one deliberately or inadvertently, there is transfer of current from the conducting electrode to the touching electrode. This is called direct coupling.
Capacitative coupling
y Conductor has intact insulator but, passes through a non-insulated conductor such as a metal trocar or metal suction tip
y This specifically occurs when using activation of electrode while not in tissue contact or during fulguration
y This can be avoided by using all metal trocars as a large conductive surface area dissipating energy over a wide area.
Some interesting points to know in laparoscopy y Verres needle
– Maximum flow is 2.5 L/min – 14 gauge
– External diameter 2 mm – Length is 70–120 mm
y Hasson cannula‘s maximum flow is >6 L/min y Frequency of harmonic scalpel is 55,500 Hz y Frequency of CUSA is 23,000 Hz
Q36. Classify the ablative techniques used in surgery.
Ans.
Q37. What is Photodynamic therapy? Enumerate its principles and application.
Ans.
y Also called photochemotherapy
y It involves the use of photochemical reactions through the interaction of light, oxygen and photosensitising agents.
Mechanism of action
y Usually a two step procedure.
– First step—administration of photosensitizer through topical/oral/intravenous route which is taken up by target cells and gets collected usually in the vicinity of the mitochondria
– Second step—activation of the photosensitizer in presence of oxygen with help of a specific wavelength of light either blue (405 to 420 nm called sorret band) or red (635 nm) y In skin, the photosensitizers mainly accumulate in the sebaceous glands and the
epidermal cells
y The activation of these photosensitizers causes activation of the reactive oxygen species and emission of light which is called photofluorescence
y Singlet oxygen species which are believed to be type 2 photochemical reaction are seen to predominate in this therapy
y Other mechanisms of action – Modify cytokine expression
– Increase interleukin-1 beta, interleukin 2, TNF-alfa and G- CSF
y Photosensitizing agents include aminoleulinic acid or methyl aminolevulinate. Others include porphyrins, xanthenes, phenothiazines, monoterpenes and chlorines dyes.
Indications y Actinic keratosis
y Small basal cell carcinomas y Bowen’s disease
y Acne y Photoaging
y Vitiligo, psoriasis, neurodermatitis, eczema, cutaneous T-cell lymphoma and lichen ruber planus
y Wet age related macular degeneration y Carcinoma esophagus
y Cholangiocarcinoma.
Recent addition of laser photodynamic therapy wherein laser is used to initiate the photochemical reaction has been added to this field because monochromacity of laser provides the maximum effectiveness amongst all the various light sources used.
Q38. Write a note on day case surgery.
Ans. Day case surgery is when a patient gets his procedure from first consultation to discharge after admission within 12 hours of the hospital stay.
y 12 hours to 24 hours is overnight stay y 24 hours to 72 hours is short stay surgery
y This depends on appropriate patient and procedure selection for day case surgery. Also the patient should have appropriate support system to take his care of once discharged.
Selection parameters
y Patients up to ASA III are considered for day case surgery
y Patients should have a good support system and home quite near to the facility with good and safe transport facility to bring him back in case the need arises
y Procedures should not be longer than 2 hours and minimally invasive procedures are preferred.
Steps
Patient selection and procedure selection.
Preoperative assessment
y History and physical assessment
y Medication and current comorbidity history y Informed consent
y Routine preoperative assessment such as Mallampatti grade, BMI, oral cavity examination.
Perioperative management
y Adequate analgesia in preoperative, intraoperative, infiltration at the end of surgery and postoperative period
y Adequate premedication to smoothen the anesthesia and postoperative recovery y Avoidance of opioids to avoid postoperative delirium and vomiting
y Perform surgery with as minimal access as possible and care to achieve optimum hemostasis with minimal tissue handling and dissection
y Procedures such as varicose vein surgery, hemorrhoidectomy, inguinal hernia, TURP, hydrocele, varicocele, circumcision, tonsillectomy are commonly performed in day care fashion.
Discharge
Patient is to be discharged only if:
y He has no complaints of pain, nausea, vomiting y He is accepting orally and able to pass urine y He is conscious, oriented and vitally stable
y Has no surgical complications such as reactionary hemorrhage or dressing soakage and y Has a good social support system as mentioned above.
Advantages
y Patient benefits because of the rapid recovery and early return to routine life with minimal physiological changes, less cost and less postoperative complications
y Hospital benefits because of the rapid patient turnover and economical use of resources.
Q39. Write in brief about robotic surgery.
Ans. Robotic surgery is telesurgery, i.e. the surgeon performs surgery by being away from patient through a console which manipulates the robotic instruments according to surgeon maneuvers on the console.
The robotic system used now is DaVinci system.
Parts
y Master surgeon console: On which the surgeon sits, uses his hands to manoeuvre instruments via master controllers and sees 3 -dimensions vision through the stereoviewer y Patient cart: Patient lies on this cart and the instruments are docked (fixed) into the
ports on the robot wheel cart over this table. There are 4 arms for instruments with one of them being camera port. Ports are placed as in laparoscopy and then the instruments inserted in ports through robot arms to connect them to the master console control y Vision cart: Has a binocular vision through 3-D endoscope connected to camera.
Advantages
y Stereoscopic depth perception (3-D vision)
y More range of motion due to wrist like motion present in robotic instruments which give some degrees of freedom in movement
y Improved hand eye co-ordination as the robotic camera is controlled by the surgeon and is held in steady position by robotic cart so no fatigue or tremors
y Less surgeon fatigue due to excellent ergonomics (sitting surgery) y Comparably less prolonged learning curves than with laparoscopy.
Limitations y Cost
y Learning curve
y Duration of surgery is prolonged compared to open surgery Commonly performed robotic procedures
y Gastrointestinal—cholecystectomy, pancreatic resections, bariatric surgery, colectomy, mesorectal excision, fundoplication, gastrectomy
y Urology—radical cystectomy, prostatectomy, pyeloplasty, nephrectomy y Thoracoscopic—esophageal surgery and thymectomy
y Head and neck—transoral robotic surgery (TORS) for nasopharyngeal cancer, robotic thyroidectomy
y Gynecology—hysterectomy