Thursday 2 January 2020

SOT

Abstract
An operation theater complex is the "heart" of any major surgical hospital. An operating theatre, operating room, surgery suite or a surgery centre is a room within a hospital within which surgical and other operations are carried out. Operating theatres were so-called in the United Kingdom because they traditionally consisted of semi-cir­cular amphitheatres to allow students to observe the medi­cal procedures. OT complexes are designed and built to carry out investigative, diagnostic, therapeutic and palliative proce­dures of varying degrees of invasiveness. Many such set ups are customized to the requirements based on size of hospital, patient turnover and may be specialty specific. The aim is to provide the maximum benefit for maximum number of patients arriving to the operation theatre. Both the present as well as future needs should be kept in mind while planning. Proper application of programming methods to the design of a surgical suite requires a thorough understanding of the design criteria that are important to proper sizing and arrangements of the ORs. Many innovations have been reported to the literature for patient safety and low vacuum, high flow, low resistance systems with many protective devices have become available. The establishment and working of the operation the­atre (O.T.) needs specialised planning and execution and is not a simple civil engineering work. A "civil-mechanical-elec­trical-electronic- bio medical" combo effort driven and co­ordinated by the needs, preferences and safety of the medical/ surgical team forms the basis for starting and maintain­ing an operation theatre. Anaesthesiologists, by virtue of their knowledge of the intricacies of physiology, physics and bio­medical aspects of medicine and constant proximity to the operation theatre should preferably be involved from the early stages of planning of operating theatres. Hospitals want to reduce costs and improve their financial assets, on the one hand, while they want to maximize the level of patient satisfaction, on the other hand. One unit that is of particular interest is the operating theater. Since this facility is the hospital's largest cost and revenue center, it has a major impact on the performance of the hospital as a whole. Managing the operating theater, however, is hard due to the conflicting priorities and the preferences of its stakeholders, but also due to the scarcity of costly resources. Moreover, health managers have to anticipate the increasing demand for surgical services caused by the aging population. These factors clearly stress the need for efficiency and necessitate the development of adequate planning and scheduling procedures. A patient—centered approach to facility planning starts with the single— patient room. which makes it possible to reduce disruptive noise, improve communication between caregiver and patient, involve family and significantly reduce infections. Hospital operating rooms are among the most infection-sensitive environments in health care facilities. Surgical procedures increase patient vulnerability to pathogens transmitted from surgical personnel, surgical equipment, the air and a patient’s own skin flora. Despite advancements in surgical techniques and infection-prevention methods, two out of every 100 surgeries in the U.S. result in surgical site infections (SSIs), according to the Centers for Disease Control and Prevention (CDC). Impacts on quality of care include morbidity, extended hospital stays and, in extreme cases, mortality. Laminar airflow is prevalent in both settings, but the difference in designs can be radical. In ISO Class 1 to Class 4 clean-room environments, nearly every square inch of ceiling space is dedicated to providing laminar airflow to minimize turbulence and produce predictable movement of particles away from the sterile field. Conversely, hospital operating room laminar flow systems typically consist of multiple laminar flow diffusers arranged in a variety of arrays to optimize airflow. In many cases, the arrangement of these diffusers—with large gaps for light troffers and other components—would be unacceptable by ISO Class 1 to Class 4 clean-room standards, and ultimately create, versus minimize, turbulence in the space. Given the quality of care and economic consequences of SSIs, consideration should be given to rethinking the requirements for the operating room to include some measure of contamination control and aerobiological quality standards. The technology and design practices have already been successfully implemented by critical-process manufacturers facing similar consequences in a different context. Challenges exist in the operating room setting—booms, lights and other components are obstacles that affect performance—but facing them head-on to advance the typical operating room beyond current design standards can be a worthy venture toward improving the quality of patient care and the financial bottom line of any health care facility. Hospitals are creating a new breed of surgery spaces called hybrid operating rooms. Hybrid ORs combine the surgical capacity of traditional operating rooms with the imaging capabilities of a catheterization lab, two spaces that have traditionally been distinct. Placing state-of-the-art imaging and X-ray equipment in an operating room allows for less invasive, safer procedures with faster recovery times for patients. The imaging equipment helps surgeons pinpoint the area of incision and provides instantaneous feedback during procedures. For example, endovascular neurosurgical cases, such as aneurysm operations, can now be performed more safely and efficiently in a hybrid OR. As surgeons conduct these high-risk, complex cases, high-tech diagnostic imaging increases positive outcomes, enabling neurosurgeons to transition seamlessly from a closed to open procedure, without losing critical time to transport a patient to another location for imaging. If designed with clinical flow in mind, the hybrid operating room suite can be a force for the future of interventional platforms. By combining imaging and surgical capabilities, hospitals are redefining the interventional suite, with great advantages in patient care and cost efficiency. With emergence of hybrid operating rooms comes both cultural and design implications that go far beyond the operating room itself and extend to the entire surgical suite and the hospital as a whole. Planning and design The first step in planning a hybrid OR is to seek input from each of the surgical specialists who will utilize the room. Design teams should include representatives from surgical and perioperative departments, administration, facilities, and IT. The team should also tour hybrid ORs at other hospitals to experience these new types of spaces. During the design phase, it’s critical to use the latest 3-D drawing tools to create a clear vision of the hybrid room’s elements. Once a design has been approved, a full-scale mock-up of the space should be built. This will give the team the opportunity to identify and solve any design challenges in the room before it’s constructed. Early vendor selection and coordination are also important steps, especially since the addition of imaging equipment adds spatial complications to the operating room. In particular, ceilings require careful consideration and advance planning, as both surgical and imaging equipment tend to be ceiling-mounted. With advance planning, designers have the opportunity to encourage vendors to work together to fit specific design parameters by facilitating conversations between them. Increasingly, vendors have joined forces to offer more synergistic solutions. For example, in the Geisinger Wyoming Valley Medical Center’s hybrid OR, two vendors teamed up to integrate their systems into one solution. One vendor’s boom mount was added to another vendor’s monitors required for the cath system, reducing the amount of ceiling-mounted equipment. Vendors are also working to offer systems that integrate IT with equipment. For example, it is now possible for staff to navigate a variety of different equipment systems, including surgical, video, and patient monitoring, from one centralized control panel. Layout and equipment Hybrid ORs can include a variety of imaging equipment, including either single or bi-plane, and increasingly, CT scanners (CTORs) and MRI scanners (MRORs). MRORs can range in size from 1,200 square feet to 2,600 square feet, while CTORs run from 800 square feet to 1,100 square feet. Both rooms must allow space for the control room, supply space, scrub area, locker sequence, and the generator rack room, which runs the equipment. Different zones of OT complex The location and flow of the patients, the staff and the materials form the three broad groups to be considered during all stages of design. Four zones can be described in an O T complex, based on varying degrees of cleanliness, in which the bacteriological count progressively diminishes from the outer to the inner zones (operating area) and is maintained by a differential decreasing positive pressure ventilation gradi­ent from the inner zone to the outer zone. (1) Protective zone: It includes Change rooms for all medical and paramedical staff with conveniences Transfer bay for patient, material & equipment Rooms for administrative staff Stores & records Pre & post-operative rooms I.C.U. and P.A.C.U. Sterile stores (2) Clean zone : Connects protective zone to aseptic zone and has other areas also like Stores & cleaner room Equipment store room Maintenance workshop Kitchenette (pantry) Firefighting device room Emergency exits Service room for staff Close circuit TV control area (3) Aseptic zone - Includes operation rooms (sterile) (4) Disposal zone - Disposal areas from each OR and corridor lead to disposal zone Sub areas (1) Pre-operative check in area (reception)- This is important with respect to maintaining privacy, for changing from street clothes to gown and to provide lockers and lavatories for staff. (2) Holding area- This area is planned for IV line in­sertion, preparation, catheter / gastric tube insertion, connection of monitors, and shall have O 2 and suction lines. Facility for CPR should be available in this area. (3) Induction room - (anaesthetic room). It should have all facilities as in OT, but there is controversy as to its need. One for each OT is required, ideally each is a duplicate of the other in each floor. The anaesthetic room will provide a more tranquil atmosphere to the patient than the OT. It should provide space for anaesthetic trolleys and equipment and should be located with direct access to circulation corridors and ready access to the operating room. It will also allow cleaning, testing and storing of anaes­thesia equipment. It should contain work benches, sink(s). It should have sufficient power outlets and medical gas panels for testing of equipment. (4) Post anaesthetic care units (PACU) - preferably adjacent to recovery room. These should contain a medication station, hand washing station, nurse sta­tion, storage space for stretchers, supplies and moni­tors / equipment and gas, suction outlets and ventila­tor. Additionally 80 sq ft (7.43 sq m) for each patient bed, clearance of 5 ft (1.5 m) between beds and 4 ft (1.22m) between patient bed sides and adjacent walls should be planned. (5) Staff room - Men and women change dress from street cloth to OT attire; lockers and lavatory are essential; rest room TV, etc. are desirable. (6) Sanitary facility for staff- One wash basin and one western closet (WC) should be provided for 8-10 persons. Showers and their number is a matter of local decision. Inclusion of toilet facilities in changing rooms is not acceptable; they should be located in an adjacent space . (7) The anaesthesia gas / cylinder manifold room / storage area- A definite area to be designated. It should be in a cool, clean room that is constructed of fire resistant materials. Conductive flooring must be present but is not required if non inflammable gases are stored. Adequate ventilation to allow leaking gases to escape, safety labels and separate places for empty and full cylinders to be allocated . (8) Offices - for staff nurse and anaesthesia staff­- The office should allow access to both unrestricted and semi-restricted areas as frequent communication with public is needed. (9) Rest rooms- Pleasant and quiet rest for staff should be arranged either as one large room for all grades of staff or as separate rooms; both have merits. Comfortable chairs, one writing table, a book case etc., may be arranged. (10) Laboratory - Small lab. with refrigerator for pa­thologist to be arranged. (11) Seminar room- Since staff cannot leave an OT complex easily, it is better to have a seminar room within the OT complex. Intra-departmental discussions, teaching and training sessions for staff may be conducted here. (12) Store room- This is designed to store large but less frequently used equipment in the OT. There should be storage space for special equipment after cleaning. (13) Theatre sterile supply unit (TSSU)- Within this area, following are desirable - Temperature between 18 0 -22 0 C, humidity of 40%­-50% is the aim. Air conditioned with 10-12 air exchanges per hour Storage of sterile drapes, sponges, gloves, gowns and other items ready to use. Option to store in from one side and remove from other side. Proper inventory to prevent running out of stock. (14) Scrub room- This is planned to be built within the restricted area. Elbow operated or infrared sensor operated taps / water source is ideal. It is essential to have non slippery flooring in this area. Types of OT complexes There are three main categories of operating the­atres: The single theatre suite with OT, scrub-up and gowning, anaesthesia room, trolley preparation, utility and exit bay plus staff change and limited ancillary accommodation. The twin theatre suite with facilities similar to 1, but with duplicated ancillary accommodation immediate to each OT, sometimes sharing a small post anaes­thesia recovery area. OT complexes of three or more OTs. with ancillary accommodation including post anaesthesia recovery, reception, porter's desk, sterile store and staff change. Principles to be taken into consideration while planning an O.T. (physical / architecture): Location: Low rise buildings limited to two or three storeys high are preferred because of maximum advantage of natural light and ventilation as appropriate can be derived . The OT should be separate from general 'traffic' and air movement of rest of the hospital, OT, surgical wards, intensive care units (ICU), accident and emergency department (A & E), Radiological department (X-Ray) should be closely related and access is also required to Sterilizing and disinfecting unit (SDU) and laboratory facilities. The location of the operation complex in a multi-storey building is planned on the first floor, connecting to surgical and other wards on the same floor. Adequate electric lift is planned for vertical movement from casualty on the ground floor and ENT, Orthopaedics, Ophthalmology & other wards on the floors above. Zone wise distribution of the area, so as to avoid criss­cross movements of men & machines Adequate & appropriate space allotted as per utility of the area Provision for emergency exit Provision for ventilation & temperature control, keeping in mind the need for laminar flow, HEPA filter air conditioner etc. Operation rooms: The number & size can be as per the requirement but recommended size is 6.5 m x 6.5m x 3.5 m. Glass windows can be planned on one side only. Doors: Main door to the OT complex has to be of adequate width (1.2 to 1.5 m). The doors of each OT should be spring loaded flap type, but sliding doors are preferred as no air currents are generated. All fittings in OT should be flush type and made of steel. The surface / flooring must be slip resistant, strong & impervious with minimum joints (eg. mosaic with cop­per plates for antistatic effect ) or jointless conductive tiles/ terrazzo, linoleum etc., The recommended minimum conductivity is 1m ohm and maximum 10m Ohms. Presently the need for antistatic flooring has dimin­ished as flammable anaesthetic agents are no longer in use. Walls- Laminated polyester or smooth paint provides seamless wall; tiles can break and epoxy paint can chip out. Collusion corners to be covered with steel or alu­minium plates, colour of paint should allow reflection of light and yet soothing to eyes. Light colour (light blue or green ) washable paint will be ideal. A semi-matt wall sur­face reflects less light than a highly gloss finish and is less tiring to the eyes of OT team. Operation Table: One operation table per OT Electric point: Adequate electric points on the wall (at < 1.5 m height from the floor) (discussed later) X-Ray illuminators: There should be X-ray film illu­minators preferably recessed into the wall. Scrub area: to be planned for at-least for 2-3 persons in each OT. There has to be a preparation room in clean zone Corridors not less than 2.85 m width for easy movement of men, stretcher & machines Separate corridors for uses other than going into OT. Rooms for different persons working in OT & for different purpose (it should be as per zone & size ) Gas and suction (control, supply & emergency stock) for all OTs & areas where patients are retained. Oxygen, gas and suction pipe to be connected with central facility and standby local facility should also be available. Provision for adequate & continuous water supply: Besides normal supply of available water at the rate of 400 litres per bed per day, a separate reserve emergency over head tank should be provided for operation theatre. Elbow taps have to be 10 cm. above wash basins. Proper drainage system. Pre-operative area with reception with separate designated area for paediatric patients is desirable. Adequate illumination with shadow less lamps of 70,000-120,000 Lumens intensity, for assessing patient colour and tissue visibility. The safety in working place is essential, and fire extinguishers have to be planned in appropriate zone. Provision for expansion of the OT complex should be borne in mind during planning stages itself. Recommendations on the number of OTs required. It is observed that out of all surgical beds, of the hospital, 50% of patients are expected to undergo surgery. Thus for 100 beds, with average length of stay of 10 days for each patient, 10 operations per day can be performed. In general, multiuse OTs, instead of multiple OTs of­fer advantages of efficient man power utilization, economi­cal maintenance and better training of supporting staff. In a 300 bedded hospital (with 150 surgical beds), one OT complex with 3 OTs for General Surgery, Gynaecology, Orthopaedics/ENT, one for Endoscopy and one for Septic. OT will be required with 8 hours a day working duration. Ventilation Ventilation should be on the principle that the direction of air flow is from the operation theatre towards the main entrance. There should be no interchange air movement between one OT and another. Efficient ventilation will control temperature and humidity in OT, dilute the con­tamination by micro-organisms and anaesthetic agents. There are two types of air conditioning systems : re­-circulating and non re-circulating. Non re-circulating systems heat / cool the air as de­sired and convey it into the operating room with ideally 20 air exchange per hour. Air is then exhausted to outside. Anaesthetic agents in the OT air are also automatically removed. These are thus ideal but are expensive. The circulating system takes some or all of the air, adjusts the temperature and circulates air back to the room. The broad recommendations include: 20-30 air exchanges / hour for re-circulated air Only upto 80% re-circulation of air to prevent build up of anaesthetic and other gases Ultraclean laminar air flow - the filtered air delivery must be 90% efficient in removing particles more than 0.5m m. Positive air pressure system in OT: It should en­sure a positive pressure of 5 cm of water from ceiling of OT downwards and outwards, to push out air from OT. Relative humidity of 40-60% to be maintained Temperature between 20 0 -24 0 C. Temperature should not be adjusted for the comfort of OT personnel but for the requirement of patient, especially in pediatric, geriatric, burns, neonatal cases etc. Pendant services Two ceiling pendants for pipeline services should be designed; one for surgical team and one for anaesthetist . Anaesthetic pendant should be retractable and have lim­ited lateral movement and provide a shelf for monitoring equipment. It should have oxygen, nitrous oxide, four bar pressure medical compressed air, medical vacuum, scav­enging terminal outlets and atleast four electric sockets. Piped gases in the OT Automatic / semi-automatic fail safe manifold room to be designed. Two outlets for Oxygen and suction and one for N 2 O are a minimum in each OT. Pipeline supply system should be able to cut off from mainline if the problem occurs anywhere along the delivery hosing / tubing. Scavenging The method of scavenging should be decided during planning stage of OT .US and International standards are available for scavenging but it is ideal to plan the type of system (active / passive) and number and location of scav­enging outlets beforehand. Electrical All electrical equipment in the OT need Proper grounding In the past, isolated power systems were preferred when explosive agents were being used. They have the advantage of a transformer using grounded electricity and there is no risk to the patient or machines if a machine gets faulty. The grounded systems as used at homes offer pro­tection from macro shock but devices may lose power without warning. Life support systems, if in use could be disturbed. Criteria ideal with respect to electricity in OT complex: Use of circuit breakers / interrupters is desirable if there is an overload or ground fault. Power line of 220 Volts Suspended ceiling outlets should have locking plugs to avoid accidental disconnection. Insulation around ceiling electrical power sources should withstand frequent bendings and flexings. They should not develop cracks and should not damage wires. Wires inside rigid or retractable ceil­ing service column can help to some extent Wall outlets to be installed 1.5 m above ground. Use of explosion proof plugs. Multiple outlets from different electrical line sources should be available. Electrical load calculation should be based on, equip­ments likely to be used and appropriate current car­rying capacity cords to be used. Emergency power: OT electrical networks need to be connected to the emergency generators with au­tomatic two way changeover facility. Lighting Some natural daylight is preferred by staff . Where possible, high level windows which give a visual appre­ciation of the 'outside world' can be considered in the OT. General lighting: Colour corrected fluorescent lamps (recessed or surface ceiling mounted) to produce even illumination of at least 500 Lux at working height, with minimal glare are preferred . Means of dim­ming may be needed during endoscopies. To mini­mize eye fatigue, the ratio of intensity of general room lighting to that at the surgical site should not exceed 1:5, preferably 1:3. This contrast should be maintained in corridors and scrub areas, as well as in the room itself, so that the surgeon becomes accustomed to the light before entering the sterile field. Colour and hue of the lights also should be consistent. About 2000 Lux light is needed to asses the patients colour. White and glistening / shiny body tissues need less light than dark and dull tissues Operating area: Overhead light should be shadow less and give 25000-125000 Lux of light (50000 to100000 Lux at the centre and at least 15000 Lux at the pe­riphery). About 10-12 inch of focus of light gives adequate illumination both at depth as well as surface of body. Lights should be freely movable both in horizontal and vertical ranges. Pendant systems are preferred. OT light should produce blue white colour of daylight at spectral energy range of 50000K (35000-67000­ kelvin acceptable) Halogen lights produce less heat and hence pre­ferred. OT light should not produce more than 25000 mw/cm 2 of radiant energy. Elimination of heat by dich­roic reflectors (cold mirrors) with heat absorbing re­flectors or filters should be available along with the luminaire. An auxiliary light for a second surgical site is often beneficial UPS of adequate capacity to be installed after con­sidering OT light, anaesthesia machine, monitors, cautery etc until the backup generator takes over In endoscopic OTs, a reduced lighting is sometimes recommended. A grazing light over the floor can be helpful. Anaesthesia equipment and monitoring needs. At least one anaesthesiologist should be in the team involved in planning an OT. It is imperative that certain mandatory considerations with respect to the anaesthetic equipment and monitors be planned during the planning and design stage itself. Personal, practice and cost preferences may influence the plans. Communications Telephones, intercom and code warning signals are desirable inside the OT. One phone per OT and one exclu­sively for use of anaesthesia personnel is desirable. Inter­com to connect to control desk, pathology and other OTs as well as use of paging receivers (bleeps) is also ideal. A code signal, when activated, signals an emergency state such as cardiac arrest or need for immediate assistance.