Operating room requirements for neurosurgical procedures

Operating Room Requirements for Neurosurgical Procedures Carol Blazier, RN, BSN, CNRN,

CNOR

An operating room (OR) setup must be standardized to ensure safe and efficient operating conditions for neurosurgical procedures. This article reviews the basic OR setup at the Barrow Neurological Institute for neurosurgical procedures, the requirements for surgical equipment and supplies, and equipment storage and maintenance. Anesthesia equipment and the special requirements for pediatric, intracranial, spinal, and stereotactic procedures are also discussed. Copyright 9 1998 by W.B. Saunders Company

he setup of an operating room (OR) is critical for safe and

T uninterrupted operating conditions and for a rapid, appropriate response to surgical and anesthetic emergencies that may occur. Consequently, standards for an OR setup must be established by each surgical institution. At the Barrow Neurological Institute (BNI), we are fortunate to have six ORs dedicated to neurosurgery, a situation that is unusual in today's changing health care climate. In contrast, many ORs must accommodate cases from every surgical subspecialty, sometimes changing from case to case. This article reviews the optimal configuration of a basic neurosurgical OR setup and its adaptation for complex, specialized neurosurgical procedures. The presentation is specific to our institution and therefore to neurosurgical procedures. We hope, however, that our experience can be generalized to facilitate meaningful planning for neurosurgical OR setups in other facilities.

arm, with a control desk at the center of the department. Each OR shares a substerile area and a scrub sink. The top of the T contains an equipment storage area, the office of the head nurse, an office for the anesthesiologists, a photography office, a darkroom for radiography, the desk area, and an instrument processing area. The stem of the T is made up of the sterile press, two ORs, an instrument cleaning room, a conference room, the postanesthesia care unit (PACU), the holding area, the staff locker and lounge area, and a storage area. When planning an OR for neurosurgical procedures, the room size, location, needs of the neurosurgical procedure, the patient's age, and room use must be considered. The ideal size of an OR would range from 400 to 600 square feet. 1 Ideally, the neurosurgical OR would be located close to the PACU, the neurointensive care unit (NICU), and the radiology department. This configuration minimizes the amount of time and distance needed to transport patients to the NICU or radiology department.

Basic OR Setup

From the Division of Nursing, Barrow Neurological Institute, Mercy Healthcare Arizona, Phoenix, AZ. Address reprint requests to Carol Blazier, RN, c/o Neuroscience Publications, Barrow Neurological Institute, 350 W Thomas Rd, Phoenix, AZ 85013. Copyright 9 1998 by W.B. Saunders Company 1092-440X/98/0101-000558.00/0

A basic OR setup (Fig 2) can accommodate any neurosurgical procedure, from a straightforward shunt procedure to the most complicated craniotomy. The operating table is central to the OR and all surgical activity. Electric operaling tables, with a battery backup, permit ease of movement and patient positioning. However, manual operating tables are common in many ORs and can adequately move and position patients. Neurosurgical procedures require that the OR table be placed in many positions. Many procedures also require the addition of a three-pin head holder for head fixation. The supine position is frequently used for craniotomies and anterior spinal surgery (Fig 3). The prone position is commonly used for posterior spinal, posterior fossa, and skull-base surgery (Fig 4). Other positions used during neurosurgical procedures include the lateral, park bench, and sitting positions (Figs 5 to 7). A thick foam pad is used to ensure the patient's comfort and to p~:e~cent complications related to prolonged immobilization during lengthy neurosurgical procedures. Sequential compression stockings are used as indicated by the attending physician's preference and the patient's need for the prevention of venous stasis and thrombosis. Typically, the anesthesia machine and ventilator are positioned at the head of the OR table. At our institution, after anesthesia has been induced, the machine is moved according to the needs of the surgical procedure. Within each of our ORs, anesthesia columns are located at both ends of the room to permit flexibility in moving the anesthesia machine. For example, a craniotomy would require the anesthesia machine be moved alongside the OR table (Fig 8). In many institutions, however, the operating table is moved to facilitate surgery.

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Operative Techniquesin Neurosurgery,Vol 1, No 1 (March), 1998: pp 2-13

Description of the Neurosurgical OR ORs used for neurosurgery must be designed to accommodate a variety of cases. Neurosurgical procedures include intracranial, spinal, stereotactic, peripheral nerve, and shunting procedures. At times, the OR must also accommodate neuroradiological studies and procedures such as intraoperative angiography. Consequently, the equipment used in a basic OR setup (Table 1) must be adaptable to changing needs. For example, a room setup must be easily converted for complex cranial and spinal neurosurgical procedures that require additional equipment (Table 2), supplies, and personnel.

Physical Layout of the OR At our institution, the physical layout of the surgical department (Fig 1) resembles a T. The ORs are located along each

TABLE 1. Basic OR Equipment Anesthesia cart and machine Back table Cautery unit Compression stockings unit Garbage and liner containers Kick buckets Mayo stands (three) OR table Positioning equipment (arm boards, axillary roll, bean bag, chest rolls, foam padding, linen, pillows, sandbag, tape) Preparation stand Ring stands (double/single) Suction canisters Thermia unit

Space and institutional habit will often dictate which equipment is moved. An anesthesia cart with drugs and supplies routinely stays in place but also can be moved as needed. Electrophysiological monitoring machines, unipolar and bipolar cauterization units, a motor unit for sequential compression stockings, two to four suction cannisters, trash containers, and kick buckets are routinely positioned at the foot of the bed. The sterile portion of the OR is located opposite the entrance of the OR. Mayo stands, a back table, and a double-ring stand are located here. The preparation stand, a nitrogen tank, a neurosurgical microscope, and a chair for using the microscope complete the circle around the OR table. Sterile supplies are set up on the back table. Instruments can be set up on Mayo stands or an overhead table. Two Mayo stands are used for the setup of the instruments. Mayo stands can be adjusted as the patient's position requires during surgery. Mayo stands allow easy access to the patient when a fat, fascial, or bone graft is needed, or if intraoperative angiography is required. Mayo stands can be easily moved as indicated by circumstances. With the overhead table, all the instruments are directly in front of the scrub nurse. When in use, the drapes are kept off the patient's body. Table adjustment is controlled by the anesthesiologist with each change in the patient's position. Although not used at our institution, an overhead instrument table can be used for the setup of the TABLE 2. Equipment Specific to Neurosurgical Procedures Bipolar cautery unit Cell saver Electrophysiological monitoring equipment Frameless stereotactic equipment Hair clippers Head light Hemostatic agents (Avitene, bone wax, cottonoids, fibrillar, Gelfoam [UpJohn, Kalamazoo, MI], irrigation, Nuknit [Johnson and Johnson, Arlington, TX], oxycel, and Surgicel [Johnson and Johnson, Arlington, TX]) Image intensifier (C-arm) Laser* Microscope chair Microscope and television monitors Microvascular Doppler* Overhead instrument table* Positioning equipment (Caspar head holder, horseshoe head holder, Leyla attachment, skull clamp and table attachments, radiotucent skull "clamp, and Wilson frame) Precordial Doppler Stereotactic equipment Ultrasonic aspirator Video equipment (microscope, thoracoscope, ventriculoscope) Weights Radiograph cassette holder *Optional depending on institutional preference and need. OPERATING ROOM REQUIREMENTS

surgical instruments. Institutional, neurosurgeons', anesthesiologists', and surgical nurses' preferences for Mayo stands or an overhead table determine the choice. Drills, frequently required during neurosurgical procedures, are placed on a Mayo stand or in a single-ring stand. Both stands keep the drill safely isolated away from the patient and OR personnel. The OR neurosurgical microscope and chair are positioned at the head of the OR table. They are brought into the field and positioned as needed for the procedure. Each of our ORs is equipped with television monitors, usually two, which allow the microscopic portion of the procedure to be viewed by the anesthesiologist and OR personnel. The monitors help the anesthesiologist to monitor blood loss and the OR personnel to anticipate the needs of the surgeon. Radiographic view boxes, a supply cabinet, and a desk area complete this basic setup. At our institution, each OR is also equipped with a computer for charting.

Specialized Equipment Needs Pediatric equipment. Specialized anesthesia and surgical equipment is often needed for pediatric neurosurgical procedures. The equipment usually required can be organized into a box or cart for convenience and rapid access in an emergency. At our institution a pediatric cart kept in a general storage area can be easily wheeled into the OR for a pediatric procedure. The cart contains items such as pediatric sizes of airway equipment, blood pressure cuffs, pulse oximetry probes, intravenous (IV) supplies, and Foley catheters. Latex-free cart. A box or cart stocked with latex-free items (Table 3) is helpful when preparing for a neurosurgical procedure on a patient who is latex sensitive. The cart not only provides the necessary latex-free supplies for anesthesia and surgery but also reminds health care workers of the precautions needed (Table 4) for latex sensitivity and allergies. 2 Code cart. A code cart is mandatory and must be readily available to each OR in case of an emergency. The functioning of the defibrillator must be checked daily. At our institution, one wheeled code cart is shared by six operating rooms. The PACU adjoining our ORs has a separate code cart, which may be used as a backup in the case of simultaneous emergencies. Positioning equipm.ent. The type of positioning equipment is determined by the procedure, the surgeon's and anesthesiologist's preference, and the patient's need. Rigid head fixation is often required for neurosurgical procedures. A three-pin head holder is frequently used for craniotomies and for some spinal procedures. Stereotactic procedures require a special frame with four skull pins. A horseshoe head holder is used for cranial remodeling procedures. This head holder allows mobility of the scalp flap. A Caspar head holder (Aesculap, San Francisco, CA) is used for anterior cervical spine plating procedures. This head holder provides head and neck support and neutral alignment. Positioning for spine and posterior craniotomy surgery requires chest-roll positioning or the use of a spinal frame such as a Wilson (Zimmer, Warsaw, I N ) o r Andrew frame. These frames allow support of the patient without compromising vital organs. A radiolucent spine frame is used for cases that require intraoperative angiography or for spinal instrumentation cases that require fluoroscopy. Specialized tables are sometimes required or requested for spinal procedures. The Jackson spinal table may be required for positioning patients with specific anatomic needs. The Jackson 3

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table (OSI, Orthopedic Systems, Inc., Union City, CA) and Andrew frame permit the patient's chest and abdomen to hang free, allowing the chest to expand adequately and avoiding compression of the vena cava. Additional adjuncts for positioning include egg-crate foam padding, sandbags, bean bags, pillows, adhesive tape, foam head cradles or donuts, arm supports, and gel pads. Foam head cradles are used for patients during prone positioning. They also can be used to support the torso of a pediatric patient placed in a prone position.

Storage Storage space within the OR is limited. In the neurosurgical department, storage areas consist of a substerile area between two ORs, an equipment storage room, a sterile instrument

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Fig 1. Physical layout of BNI OR. (Reprinted with permission from Barrow Neurological Institute.)

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storage room, a clean instrument room, and an anesthesia supply area. The substerile area between two ORs contains positioning equipment, linens, warm irrigation and IV fluids, an autoclave, and a blood refrigerator. The equipment storage room is filled with supplies and equipment that must be available but are not needed for every case. Examples of such equipment are head lights, positioning equipment, endoscopic video monitors, stereotactic frames, the pediatric cart, warmers, the microvascular Doppler unit, and a Cavitron ultrasonic surgical aspirator (Valley Lab, Stamford, CN) or Selector (Elekta, Atlanta, GA) motor unit. Additional anesthesia supplies for stocking and those not used routinely are available within the department. An emergency airway cart with a flexible bronchoscope and other a~rway supplies must be available for difficult intubations and the placement of doublelumen endotracheal tubes.

CAROL BLAZIER

Assistant

Fig 2. Basic OR setup, (Reprinted with permission from Barrow Neurological Institute,)

Evoked potential and EEG monitoring

Microscopes There are six neurosurgical OR microscopes and supporting video equil~ment. Normally, a storage area must be allotted for the safe storage of a microscope when not in use. Because the microscopes are used often, one is maintained in each OR. A C-locker (Milcare, Health Division of Hermann Miller, Zea-

Fig 3. Supine position showing three-pin fixation. (Reprinted with permission from Barrow Neurological Institute,) OPERATING ROOM REQUIREMENTS

land, MI) is maintained with additional microscope attachments and light bulbs.

Sterile Supplies The sterile instrument room is stocked with instrument trays, surgical implants, additional separate instruments, and disposable supplies. Racks are organized with basic trays (eg, soft tissue, craniotomy, laminectomy, anterior cervical discectomy), and specialty trays for items such as microinstruments; aneurysm clips; transsphenoidal instruments; spinal instrumentation and implants; endoscopic cameras, instruments and supplies; stereotactic instruments; retractors; and drills. Clockers mounted on the walls are filled with separate instruments, disposable items, and a variety of shunt products. A cupboard is maintained for freeze-dried bone, dural, and cranial implants. Frozen implantable products such as bone and Gliadel wafers (manufactured for Rh0ne-Poulenc Rorer Pharmaceuticals, Inc, Collegeville, PA, by Guilford Pharmaceuticals, Inc, Baltimore, MD) are stored in a freezer in the hospital laboratory. Sutures, gloves, electroencephalogram (EEG) monitoring supplies, and intracranial pressure monitoring supplies also are available. Emergency trays such as a tracheotomy tray or

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Fig 4. Prone position for spinal surgery. (Reprinted with permission from Barrow Neurological Institute.) ventriculostomy tray are maintained. Pleur-evacs (Deknatel, Inc, Fall River, MA) and a variety of chest tubes are available for routine placement during transthoracic cases and for emergencies such as pneumothoraces. Within the clean instrument room, additional surgical instruments, drill bits, and implants (eg, aneurysm clips and spinal bolts, rods, plates, and screws) are available.

Pharmacy Any OR must have access to a variety of anesthetic agents and medications. These medications are stored in a drawer in the anesthesia cart, but elsewhere they may be kept in a box. Availability is important. In some ORs a staffed pharmacy is available within the surgical department. At our institution, we are connected to the main hospital pharmacy by fax and a tube system. For more immediate needs, an automated drug delivery system (Pixis) is available between ORs. This system contains small quantities of a limited number of drugs, and they can be varied based on physician's preferences and the patient's needs. This system supplies both narcotic and nonnarcotic drugs. A drug box is available for the treatment of malignant hyperthermia.

Staffing

Fig 6. Park bench position. Note head and neck flexion and rotation, (Reprinted with permission from Barrow Neurological institute.) and a circulating nurse. At our institution each case also is staffed by a neurosurgical resident, and at times, by an anesthesia resident. A cerebrovascular or spine fellow often participates in cases in his or her focused area of interest. Medical students and surgical residents with an interest in neurosurgery are routinely part of the neurosurgical team. Electrophysiological technicians participate when neurophysiological monitoring is indicated. The safe care of the patient during the surgical intervention is the focus of the entire OR team. Focusing on positioning, aseptic technique, and equipment maintenance helps to ensure the patient's safety. A cost-effective method of staffing has been instituted and consists of using scrub technicians to scrub cases and registered nurses (RNs) to circulate. A 40:60 ratio of technicians to RNs is ideal; however, a '50:50 ratio is often the reality. Previously, the OR was staffed by an all-RN staff and one licensed practical nurse scrub position. This staffing arrangement allowed the flexibility of the RNs either scrubbing or circulating during a case. Other advantages included a thorough knowledge and understanding of both roles, anticipating and preparing for the needs of the surgical team, a pooled knowledge useful for troubleshooting malfunctioning equipment or patient problems, a cooperative team effort, and a high level of employee satisfaction.

The department of neurosurgery's staffing consists of medical, nursing, and ancillary personnel. Each neurosurgical case is staffed by a neurosurgeon, an anesthesiologist, a scrub nurse,

Fig 5. Lateral position for the retroperitoneal or transthoracic approaches to spinal pathology. (Reprinted with permission from Barrow Neurological Institute.)

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Fig 7. Sitting position, (Reprinted with permission from Barrow Neurological Institute.)

CAROL BLAZIER

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Fig 8. OR setup for craniotomy and bifemoral cannulation. The anesthesia equipment is positioned along the side of the patient and OR table. (Reprinted with permission from Barrow Neurological Institute.)

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~umpoxygenator The role of the RN is multifaceted. The role requires technical and mechanical skills for setting up and troubleshooting equipment, preparedness for the procedure, and anticipation of the needs of the surgical team. These skills are acquired from on-the-job training and clinical experience. A knowledge of basic anatomy, physiology, and neurosurgical pathology is required. With additional training, the RNs are able to run the cell saver. This training saves the costs of using ancillary sources. Several nurses have completed the appropriate training to function in the role of RN first assistant. OPERATING ROOM REQUIREMENTS

The role of the scrub nurse is to prepare for the procedure, to maintain aseptic technique, to have a general knowledge of anatomy and pathology, and to anticipate the surgeon's needs. These responsibilities are challenging with the variety of cases performed and the individual preferences of the surgeons. Managerial roles for OR RNs include the roles of charge nurse and nurse manager. At our institution, the daily schedule is run by a charge nurse. This role includes scheduling; organizing to follow up cases; staffing; breaks; and planning for cases, supplies, and equipment for the next day. The nurse 7

TABLE 3. Latex-Free Supplies Steri-strips (3-M) Mastisol Mon-a-therm esophageal stethoscope Bovie pads Argyle suction tubing Davol premature feeding tubes Argyle feeding tubes 3-M dura-prep Bio-Tac ECG cloth electrodes Baxter Ambu bag no. 2K8008 or no. 2K8005 Devon Lite handles (green ones) NOTE. Silicone and mentor catheters are latex-free. Baxter (Allegiance Health Care Corp, McGaw Park, IL) denotes on packaging which items contain latex.

manager has administrative responsibilities, including finance, personnel, disciplinary action, and leadership. Ancillary personnel, such as patient care technicians (PCT) and secretarial staff, are important to the functioning of the neurosurgical OR. The PCTs assist with patient transportation, and stock and clean the OR. Secretarial support is needed for scheduling cases, billing, and other record keeping. Instrument technicians, also staffed in the department, are responsible for the cleaning, sterilization, and maintenance of instrument trays and implants. They process instruments as the day's scheduled cases advance and are relied on for instruments that are needed from case to case. The efficiency of the minimal staffing for cases can be attributed to personnel and their training. At our institution, most of the OR staff work only in neurosurgery and have a thorough knowledge of the needs of the procedures, the surgeon, and the patient. At many institutions this type of staff specialization is unfeasible. When it is possible, however, the efficiency and safety of the OR increase significantly.

OR Modifications for Specialized Procedures Necessary equipment and sterile and nonsterile supplies vary according to the neurosurgical procedure being performed. The neurosurgeon's preference, specific pathology, the patient's age, and coexisting disease also help determine the equipment and supplies needed. A basic setup can be adapted to meet the needs of every neurosurgical case. Case carts are prepared for each neurosurgical procedure. At our institution, the carts are prepared in a central sterile processing department and delivered to the OR each evening. Customized sterile packs from a manufacturer minimize the number of sterile supplies that must be opened. Specific supplies such as hemostatic agents and suture are opened TABLE 4. Latex Allergy Precautions Use only silk tape Wrap arm with cast padding or tubular stockinette Apply blood pressure cuff Must use stopcock for injections No IV ports Cover all ports with tape Use vinyl and latex-free gloves only (Duraprene TM or mactylTM) Do not use black anesthesia head straps unless covered with protective covering Use synthetic breathing bag for anesthesia circuit Use Bio-Tac ECG electrodes Remove elastic strap from 02 mask Can opener to anesthesia (to open medication vials) No latex in sterile field 8

based on the surgeon's preference. Basic instrumentation includes a neurosurgical soft tissue set, a craniotomy or laminectomy tray, a microinstrument tray, and a drill. Many specialty trays are available for use depending on the procedure and the surgeon's preference.

Craniotomy Craniotomy is a common neurosurgical procedure for intracranial pathology such as aneurysms, arteriovenous malformations (AVMs), hematomas, tumors, and seizure focus. A distinct advantage of specializing in a specific area of surgery is the efficient preparation and participation in the procedure. Knowledge of the surgeon's preferences and routine contributes to this efficiency and makes modifications possible. Specific modifications are based on the pathology, the patient's needs, and the events of the surgical intervention. T~moFs At our institution, a frameless stereotactic system is commonly used for tumors and other intracranial pathology. With frameless stereotaxy, a computer work station and sensing device correlate the patient's anatomy with a perioperative imaging study. This information provides intraoperative guidance to help the neurosurgeon localize the surgical site and identify important anatomic structures. A craniotomy case cart that contains the custom sterile packs, a craniotomy split drape, and other disposable supplies is used for all cranial procedures. Instruments necessary for this procedure include a neurosurgical soft tissue tray, a craniotomy tray, a microinstrument set, a Midas Rex drill, cranial plates, and a Greenberg retractor. A stereotactic sensing device and a drape are added when frameless stereotaxy is used. For tumor resections, all types of hemostatic agents, cottonoids, and cotton balls should be available. Bipolar cauterization is important for "all neurosurgical procedures. A Malis bipolar coagulator and bipolar cutter (CMC II; Codman & Shurtleff, Randolph, MA) with a remote control for the scrub nurse and an audible monitor is used. With this system, the scrub nurse can change the setting as the surgeon requests and the audible monitor indicates a change. The type and size of tumor determine the additional supplies needed. Bovie loops may be preferred by a surgeon for decompression of a large tumor. Ultrasonic aspiration may be required. Often extra bone wax and other hemostatic agents are necessary because of the lesion's vascularity and bony involvement. The specific microinstrumentation needed for the reseE~ion of a lesion wrapped around cranial nerves or the brain stem varies. An assortment of microdissectors, round knives, hooks, scissors, and biopsy forceps should be available to provide for surgeons' preferences. Nerve stimulation is often used during the resection of tumors near or involving a cranial nerve. This adjunct is frequently required for resection of an acoustic neuroma. A skull-base tumor may be approached transfacially. For this approach, a craniofacial team of plastic and oral surgeons work with the neurosurgical team. In addition to basic craniotomy instrumentation, craniofacial and oromaxillary instruments, a reciprocating saw, and a cranial facial plating system are necessary. CAROL BLAZIER

Finally, implantable devices may be necessary after tumor resection. Gliadel wafers (RhOne-Poulenc Rorer Pharm., Inc., Collegeville, PA) may be used for a recurrent glioblastoma. An implantable dural graft may be needed for dural closure if pericranium tissue is unavailable. These items should be available at the time of surgeon request.

Neurovascular Lesions A craniotomy for an aneurysm requires additional st~pplies, including a variety of aneurysm clips and clip appliers. At our. institution, the aneurysm clips most often used are the Spetzler (Elekta | Instruments, Atlanta, GA), Sugita (Sims Surgical Inc., Keene, NH), and Yasargil (Aesculap, | San Francisco, CA). This list, however, does not reflect the variety of aneurysm clips available for use and will vary from institution to institution. A microvascular Doppler ultrasound probe and machine may be used to assess vessel patency after clipping. During these procedures, a third suction device must be available for the sterile field in case of aneurysmal rupture. The location and size of the aneurysm will determine the approach and surgical treatment. The pterional approach is routinely used for aneurysms of the anterior circulation. The patient is positioned supine with the head turned slightly. An aneurysm of the posterior circulation (eg, posterior inferior cerebellar artery aneurysm or a vertebral artery aneurysm) would be positioned laterally and may be approached from a far-lateral approach. A giant basilar artery aneurysm may require an orbitozygomatic approach. Intraoperatively, aneurysms can be clipped, wrapped, or bypassed. A giant thrombosed aneurysm may be bypassed, the aneurysm opened, and the thrombosed component decompressed. Each surgical treatment requires the availability of specific instruments and supplies. An aneurysm's location may dictate additional supplies. For example, an aneurysm of the ophthalmic artery would necessitate the clinoid being drilled down to allow placement of an aneurysm clip. A diamond bit (Midas Rex BD-3; Midas Rex Pneumatic Tools, Inc, Fort Worth, TX) and microcurrettes are needed for this portion of the procedure and should be readily available. Whether" an aneurysm is clipped electively or emergently because of subarachnoid hemorrhage (SAH) determines the intraoperative medications administered and the need for a ventricular catheter. Often, patients with SAH will have a ventriculostomy performed preoperatively. Papaverine (30 mg/mL to 2 mL) is often administered intraoperatively for vasospasm. A cisternal catheter is placed for postoperative treatment of vasospasm.

AVMs A craniotomy for an AVM requires additional equipment and supplies for intraoperative angiography: a radiolucent skull 'clamp, an image intensifier, leaded radiography gowns, a femoral sheath and angiography catheter, dye, and a heparinized pressure line. Various bipolar cauterization tips (small to blunt) and sharp, short, and long microscissors should be available for the resection. Frameless stereotaxy also may be used for localization and guidance during an AVM resection. As with tumor resections, all hemostatic agents, cottonolds, and cottonoid balls should be readily available. OPERATING ROOM REQUIREMENTS

Seizures Typically, the treatment for intractable seizures is a two-staged craniotomy procedure. The first stage involves grid placement for localization of the seizure focus. The grid is placed in consultation with a neurologist. The patient's head and the exiting electrodes from the grid are wrapped with two kerlix dressings. One kerlix dressing is wrapped over the head with the electrodes. The second kerlix dressing covers the electrodes. The kerlix dressing is marked "no scissors" as a reminder to unwrap it and not cut it while it is over the electrodes. The patient then is monitored for 1 week in an epilepsy monitoring unit, and the area of seizure activity is identified. During the second procedure, the localized seizure area is resected.

Hematomas The surgical evacuation of hematoma is an emergency procedure. Time is the significant factor. In our institution, an OR prepared for trauma and a surgical team are available 24 hours a day. Evacuation of a hematoma requires a basic craniotomy setup.

Hypothermic Circulatory Arrest The treatment of a giant cerebral aneurysm may require the surgical adjuncts of hypothermia and circulatory arrest. The OR setup is modified by preparing two separate surgical setups, one for the craniotomy and one for bifemoral cannulation (Fig 8). The instruments for each surgical procedure are placed on Mayo stands, The patientg chest must be accessible, prepared, and draped if the sternum must be opened for emergent cardiac cannulation. The cardiopulmonary portion of the procedure requires a thermia cooling-heating unit, the cardiopulmonary oxygenator, a battery backup, and a defibrillator. In addition to the staffing required for a craniotomy, the cardiovascular (CV) team consists of a CV surgeon, a perfusionist, and CV scrub and circulating nurses.

Stereotactic Procedures Stereotactic procedures are common neurosurgical procedures. A stereotactic biopsy is performed to diagnose tumor or an infectious process. Stereotactic procedures such as a thalamotomy or pallidotomy are performed to treat movement disorders. The stereotactic implantation of a Medtronic cranioventricular device to administer medication for the treatment of Parkinson's disease is an investigative procedure. Stereotactic procedures require frame placement, transport to radiography for a computed tomography scan or magnetic resonance imaging, and return to surgery for the stereotactic procedure. Portable monitoring for an electrocardiogram, blood pressure, and oxygen saturation and oxygen per nasal cannula is needed during transportation, throughout which the anesthesiologist accompanies and monitors the patient. Before the patient returns to the OR, the stereotactic frame must be assembled. The neurosurgeon verifies coordinates, sets the frame, and performs the procedure. The procedure is performed with local anesthesia and monitored anesthesia care. Although stereotaxy is seldom as invasive as a craniotomy, there is always the potential for complications. Therefore, a setup for open craniotomy must be readily available. 9

Carotid Endarterectomy

Spinal Procedures

Carotid endarterectomy (CEA) is a commonly performed peripheral carotid artery procedure. The carotid artery is approached through a transverse or longitudinal incision in the neck. Additions to the basic setup for CEA include a vascular tray, arterial shunt, and Oximeter Shaw scalpel (Oximetrix, Inc, Mountain View, CA). Embolectomy catheters should be available. At our institution, a microscope is used routinely for CEA, and a Shaw scalpel is used for the dissection (Fig 9). Monitoring during a CEA includes standard anesthesia monitoring as well as neurophysiological monitoring. If no changes occur in the EEG during carotid artery crossclamping, the surgeon proceeds with the endarterectomy. If the EEG changes, an arterial shunt is placed. Shunting of the artery is rare at our institution. After the gross dissection of the plaque, the surgeon uses the microscope to remove any remnants of plaque. The endarterectomy is closed with 6-0 prolene suture. If a thrombus is present, a No. 2 embolectomy catheter may be passed into the artery for removal.

A basic.OR setup also can be easily adapted for spinal procedures. The same disposable custom packs used for craniotomies are used for a spinal procedure. A lap drape is added. Soft tissue, laminectomy, and microdiscectomy trays are the basic instrumentation. Routinely, the Midas Rex drill is used with an AM-8 drill bit. Specific instruments and trays are added to this setup for more complex spinal cases. An OR microscope for better light and magnification is used routinely during spinal cases to magnify the operative site for safe intervention. Common spinal pathology includes disc herniation, spinal stenosis, spondylolisthesis, instability, degenerative arthritis, congenital deformities, fractures, tumors, AVMs, abscess, and hematomas. These pathologies can be approached anteriorly, laterally, posteriorly, or transorally depending on the location and type of lesion. Transthoracic and retroperitoneal approaches allow anterolateral exposure of spinal pathology such as tumors or fractures located within the thoracic or upper lumbar spine.

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Fig 9, OR setup for carotid endarterectomy, (Reprinted with permission from Barrow Neurological Institute,)

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Bipolar Shaw scalpel 10

CAROL BLAZIER

Lumbar spine procedures. Spinal stenosis or lumbar disc herniations are common rleurosurgical spine cases. Preoperatively, the level of the pathology is verified radiologically. Lumbar spinal fusion and instrumentation cases are complex, and a variety of instruments and implants is available. The guiding principles for these procedures are safe positioning of the patient on an OR table that allows the fluoroscopy unit to be moved so that the alignment and placement of the implant can be viewed. A cell saver often is used because the potential for blood loss is high during instrumented spinal surgery. A secondary back table is used to hold additional trays of spinal instrumentation and implants. Cervical spinal procedures. Cervical spinal pathology can be approached anteriorly or posteriorly. A common anterior procedure is an anterior cervical discectomy with or without a bone graft and plating. Bone grafts may be autologous or cadaver freeze-dried graft. The plating systems used at our institution are Codman (Johnson & Johnson Professional, Inc., Raynham, MA) or Orion (Sofamor-Danek, Memphis, TN) systems. Surgeons' preference dictates the choice of plating systems. With plating, fluoroscopy is required to evaluate graft, plate, and screw placement and spinal alignment. Somatosensory evoked potentials (SSEPs) are monitored throughout the procedure. A cervical collar is placed on the patient immediately after extubation. A unique approach to odontoid pathology in patients with rheumatoid arthritis with basilar invagination is a transoral resection of the odontoid. The patient is placed in a supine position, and the head and neck are held in rigid fixation. The procedure is performed under microscopic visualization. The soft palate can be incised, and soft tissue is dissected with electrocauterization. The odontoid is identified and removed with the drill, microcurrettes, and Kerrison rongeurs. The resection may be evaluated by filling the cavity with dye and taking a radiograph. The wound is irrigated with antibiotic solution and closed under the microscope. A feeding tube is placed. Typically, the endotracheal tube is left in place at the close of the procedure because of the risk of oropharyngeal swelling. A posterior fusion is performed at a later stage to stabilize the occipitocervical junction. For selected cases of odontoid fracture, odontoid screw fixation may be the surgical treatment of choice. The patient is placed supine, and the neck is extended. Anteroposterior and lateral C-arms are positioned (Fig 10). An Apfelbaum retractor (Aesculap, San Francisco, CA) is placed to maintain exposure. A cannulated screw set and mini-driver drill (Sofamor-Danek, Memphis, TN) are needed in addition to the basic spinal trays. Under biplanar fluoroscopy, the surgeon inserts a Kirschnerwire, drills, and places a self-tapping, partially threaded lag screw.

A posterior cervical fusion of the occiput and cervical spine can be performed with a threaded titanium rod secured in place with Songer cables (AcroMed Corp, Cleveland, OH). Again, the patient is in a prone position with the head and neck fixated rigidly. SSEPs are monitored. Specific instrumentation includes a BendMeister Rod Bender (Sofamor-Danek, Memphis, TN) used to shape the titanium rod, a flexible endotracheal stylet used as a template, and a Songer instrument set to pass and secure the Songer cable. To fuse the occipitocerv!cal junction, bone graft is taken from an iliac crest. Thoracic spine surgery. A transthoracic approach to spinal OPERATING ROOM REQUIREMENTS

pathology requires lateral positioning on a bean bag with an axillary roll and protective padding. The patient is positioned, prepared, and draped in a manner satisfactory to both the CV surgeon and neurosurgeon. At our institution, the neurosurgical OR is a separate department from the general and cardiovascular ORs; therefore, instruments for the transthoracic exposure must be borrowed from the general or CV ORs. The CV surgeon exposes the surgical site. Often a rib is resected and used for bone graft later in the case. The level of pathology is verified with fluoroscopy. A thoracic retractor is placed to maintain exposure. This approach is often used for tumor or fractures of T l l or T12. A corpectomy is performed at this level. A Harm's cage (Depuy-Motech, Warsaw, IN) is placed. A Z-plate (Danek, Memphis, TN) may or may not be placed. Long spinal instrumentation is often required. A laparotomy tray and thoracotomy tray are needed for opening and closing the incision. Weck clips and long silk ties are needed for vessel ligation. Fine CV suture must be available for arterial vessels if needed. Fluoroscopy is used to view the cage, to place the plate and screws, and to ensure spinal alignment. The CV surgeon inserts the chest tube and closes the wound. The positioning for a retroperitoneal approach is similar. Long instruments are needed. A Bookwalter retractor is placed for exposure, and the pathology is addressed. A thoracoscopic approach to spinal pathology, such as a herniated thoracic disc or a biopsy of a thoracic lesion, is a less invasive procedure and can be done by video-assisted thoracoscopic surgery. A thoracoscope and video equipment are necessary (Fig 11). Three ports are placed, and endoscopic instruments are used. Fluoroscopy is used to identify the appropriate level. A retraction system called AESOP (Computer Motion, Goleta, CA), a robotic attachment, is used at our institution. After the pathology has been addressed and hemostasis has been obtained, a chest tube is placed and the access port sites are closed. A thoracotomy tray and supplies must be readily available if the need to open the chest arises. Other approaches to spinal pathology also are possible. A fiber-optic bronchoscope is available for cases that require a double-lumen endotracheal tube or awake fiber-optic intubation. SSEPs are monitored preoperatively and intraoperatively. Specific trays, drills, and supplies are gathered for each case.

Pediatric Procedures Neurosurgical procedures on children represent an important number of diverse procedures. Neuropediatric patients range from neonates to teenagers. The experience of surgery and being separated from their parents can be very frightening for pediatric patients. Poor thermal regulation 3 and loss of body heat related to body size require the use of heating units such as thermal blankets, overbody warmers or warm-air blowers (Bair Hugger, Augustine Medical Inc, Eden Prairie, MN), and a thermal regulation system that warms and cools the OR rapidly and accurately.

Shunt Placement Placement of a shunt system is another common procedure. The basic equipment required includes a shunt tray, a drill, and a shunt passer. A disposable custom pack designed for minor neurosurgical procedures is used. A drape reflecting the surgeon's preference is added. Several types of shunt products

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A-P C-arm

Lateral C-arm

"

Fig 10. OR setup for odontoid screw fixation includes biplanar fluoroscopy. (Reprinted with permission from Barrow Neurological Institute.)

Surgeon

Anesthesia

Scrub nurse

are available for the treatment of hydrocephalus. Again, the surgeon's preference dictates the choice of product implanted. Care is taken to prepare the hair with betadine scrub, paint, and gel to avoid complications, including infection. The shunt product is soaked in a bacitracin solution before it is placed. A sample of cerebrospinal fluid (CSF) is sent to assay culture and sensitivity, gram stain, protein, and glucose. The increased possibility of a latex allergy in patients with myelomeningoceles should be considered. If this information is unknown, the case should be set up with latex-free gloves and only latex-free products used should be until the presence of an allergy is ascertained. Shunt revisions are performed for shunt malfunctions, occlusions, infections, or other complicating factors. With an infection, a CSF sample is sent for laboratory analysis. An external ventricular drainage system is placed until the CSF infection clears with treatment. Endoscopic shunting procedures are another treatment option. The neurosurgeon may use a ventriculoscope to view the ventricles and to place a ventricular catheter. Ventriculoscopic procedures to open cyst walls or to enlarge an area of 12

F,Oooitco, stenosis may be performed on selected patients. The appropriate ventriculoscopic and endoscopic equipment is gathered. Warm Ringer's lactate solution is used as an irrigating fluid, and the surgeon and assistant monitor the outflow of the irrigation fluid.

MyelomeningoceleRepairs A myelomeningocele is repaired as soon as possible after birth. The neonate is transported to the OR in a warmed isolette. The myelomeningocele is covered with moist dressings. After intubation, the neonate is placed in a pediatric-sized foam head cradle. The head and neck are supported with another head cradle or towels. An overhead warmer and thermal blanket are used, and the room's temperature is raised. The myelomeningocele is prepared gently, and care is exerted not to decompress the sac. When meningocele are large, a plastic surgeon may be consulted to close the wound. A rotational flap and skin graft may be needed. A dermatome, blade, mineral oil, and mesher are necessary for the skin graft. After closure, neonates are positioned on their sides to avoid placing pressure on the CAROL BLAZlER

Neuroanesthesia

ndoscope. viaeo monnors

/

Assistant surgeon Fig 11. OR setup for a thorascopic procedure. (Reprinted with permission from Barrow Neurological Institute.)

Assistant surgeon Neurosurgeon"

Endoscope video monitor

surgical site. They are then transported back to the NICU for postoperative care.

Scrub nurse

to decrease heat loss while the bone flap is being remodeled. The remodeled flap is attached to the cranial bone. Hemostasis is ascertained, and the wound is closed.

Cranial Remodeling Cranial remodeling procedures are approached by a craniofacial team, composed of a neurosurgeon, plastic surgeon, and an oral facial-maxillary surgeon. The patient's head is positioned on a horseshoe head holder, and the plastic surgeon and resident open the scalp flap. Hemostasis with bipolar and unipolar cauterization is imperative. Because of risk of significant blood loss, blood products must be immediately available in the OR. At our institution, blood products are received from the blood bank preoperatively and stored in the refrigerator within the department. Bone flap removal is associated with risks of bleeding; therefore, hemostatic agents and cottonoids must be immediately available. An extra back table is set up for the plastic surgeon's work area. A microdrill, wire, calipers, and pencil are available for the surgeon as he or she remodels the cranial bone flap. The scalp flap can be rolled over the exposed cranium, or the cranium can be covered with a warm moist laparotomy sponge

OPERATING ROOM REQUIREMENTS

Conclusions The efficient function of the OR during elective and emergent neurosurgical procedures depends on the availability of the necessary equipment, supplies, and OR personnel. With adaptations, a basic OR setup for neurosurgical procedures can accommodate the equipment and supplies required for most neurosurgical procedures.

References 1. Gruendemann BS, Fernsebner B (eds): Comprehensive perioperative Nursing. Boston, MA, Jones and Barlett, 1995 2. Levy JH: The allergic response, in Barash PG, Cullen BF, Stoelting RK (eds): Clinical Anesthesia. Philadelphia, PA, Lippincott-Raven, 1997 3. Vender JS, Gilbert HC: Monitoring the anesthetized patient, in Barash PG, Cullen BF, Stoelting RK (eds): Clinical Anesthesia. Philadelphia, PA, Lippincott-Raven, 1997

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