Inside the Operating Room (Orthopedics)

Inside the Operating Room (Orthopedics)

1. Inside the Operating Room Randolph Tulsie Medical Intern

2. Background Since the discovery of germs as causative agents for various disease states much emphasis has been placed on providing an aseptic environment of invasive medical and surgical therapies. In 1867, Joseph Lister began his work on the Practices of Asepsis in an attempt to “avoid decomposition of the injured part”. His core practices included: Phenol Spray about operation site Instrument Sterilization Surgeon’s Hand washing

3. Background The modern operating room or theatre is a purpose-built aseptic environment in which surgical procedures are carried out by a team of medical professionals. Great emphasis is placed on its design, location, and individual components as well as on the actions of its occupants in efforts to maintain an optimal atmosphere for effective surgical outcomes

4. OR Location Ideally all operating rooms should be grouped together in a dedicated part of the hospital; sometimes the unit is called a operating suite. Positioned in close proximity to: Emergency Room ICU/HDU Radiology Department CSSU Blood Bank/Lab Limited communication with general public space such as wards and waiting areas.

5. OR Design SIZE -The minimum inpatient OR size remains 400 square feet to provide flexibility and accommodate the amount of equipment used in traditional inpatient procedures. Most operating theatres are designed in theatre suites linked by a double or single corridor. It is conventional to think of theatres in four zones

6. Zones of the Theatre

7. OR Environment

8. Ventilation Airborne Contamination accounts for about 95% of all wound contaminations. Bacteria from the Skin and Upper respiratory tract can be shed by talking and moving. OR Ventilation systems utilize Bacteria free air to create a positive pressure area within the operating room. Clean air is fed via ceiling diffusers into the room and vented through small vents just above the floor, as well as through an open door. This unidirectional flow prevents airborne bacteria from entering the sterile field.

9. General Operating Theatre Equipment

10. Diathermy This is an electrical device used to achieve haemostasis while dissecting tissue. It utilizes a high frequency Alternating Current (AC) discharged from a handheld device to heat up body tissues within a small region; to temperatures of up to a 1000 degrees C; vaporizing it to cut or coagulating proteins. At 400kHz to 10MHz, diathermy frequencies exceed the 50hz threshold for neurovascular stimulation. Two Main Types Monopolar Bipolar

11. Diathermy Monopolar Circuit comprises of an active handheld electrode and a patient plate electrode Plate electrode requires at least 70cm2 contact to dry shaved skin for safe use. Avoid placement on bony prominences or metallic implants B ipolar Lower Power System which utilizes a forceps instrument to deliver the acting current. The current is passed across a small region of tissue held between the forceps. No patient Plate electrodes needed Allows for Precise and delicate tissue handling

12. Diathermy Modes CUT – continuous low voltage output, leads to heating up of intracellular fluid with subsequent vaporization and tissue destruction

13. Diathermy Modes COUG – High Voltage Pulses are administered slowly heating up the tissue, leading to protein denaturation and vessel coagulation

14. Diathermy Modes

15. Tourniquets Compression devices used on the extremities to promote a bloodless field. Should be used with caution to prevent irreversible tissue damage during surgery. Used at Minimum pressure for minimum time

16. Contraindications to Tourniquet Use Peripheral Arterial Disease Diabetes Predisposition to VTE Sickle Cell Disease AVMs Local Anaesthesia

17. C-Arm and Image Intensifiers The use of C-arm fluoroscopy in intraoperative orthopaedic procedures has become an important tool in modern orthopaedic surgical practice. It enhances the technical proficiency of the surgeon in addition to reducing the morbidity and length of hospital stay of the patient.

18. Fluoroscopy The Fluoroscopy system comprises of : X-ray Tube C arm Image Intensifier Image intensifiers are utilized to convert low energy radiation into visible light images for image capture. Image intensifiers allow for high resolution images while ensuring the lowest possible dose of radiation.

19. Image Intensifiers

20. Radiation Exposure and Safety Radiation exposure from the C arm is primarily through scattered radiation off the patient during imaging. It is highest on the X ray tube side of the c arm near the patient. Steps to reduce Exposure Limit Beam On Time Stand as far back from the patient as possible during imaging (2m) Ensure the C Arm is close to the patient; reduces air scatter Use Thyroid shields and Lead Aprons Reduce the use of the magnification setting Never be in the direct beam path