The following are frequently asked questions regarding our company and our services. If you cannot find the answer to your particular question on this list, feel free to call Biotronic. Our neural monitoring technologists and staff will be happy to answer any questions you may have.
Our staff is drawn primarily from post baccalaureate ranks. We have a tradition of generally training our own staff in the principles and techniques of intraoperative monitoring. We select our job candidates from the fields of biological sciences such as pre-medicine, microbiology, biomedical engineering, etc.
We have instituted several procedures which allow us to develop and maintain quality skills in our staff. We have a comprehensive in-house training program in which our neural monitoring technologists receive extensive classroom instruction in the principles of intraoperative neurophysiological monitoring. The skills development of our staff is tracked using performance evaluations to determine their proficiency in a comprehensive range of core competencies. Neural monitoring technologists receive one-on-one instruction and supervision in the operating room.
Biotronic supplies all capital equipment necessary to implement a complete surgical monitoring program. When you contract for surgical monitoring services, it is our obligation to supply the necessary state-of-the art equipment. The only expense to the hospital is for consumable items.
Our neural monitoring technologists at Biotronic have extensive skill and experience in neuromonitoring and can monitor a patient continuously throughout a procedure to make sure they do not suffer from brain, spinal cord, or nerve root damage. Unattended monitoring systems such as the NuVasive® NeuroVision JJB System and the Medtronic NIM-Spine System allow surgeons to monitor surgery directly, a convenient option. However, having a neural monitoring technologist present in the operating room to focus all their attention on continuously monitoring the patient, and having a certified professional available via remote neural monitoring to interpret the data and offer their expertise, may enhance the safety of the procedure, give the surgeon peace of mind, and further reduce the risk that the patient will sustain permanent neural damage following surgery. If a change in the patient's condition does occur during surgery, a surgeon working with a knowledgeable team may be better equipped to handle any situation that arises and take appropriate action.
With our highly-skilled staff and extremely diverse client caseload, we have within our organization all the skills necessary to perform any type of routine or advanced intraoperative neurophysiologic monitoring, from simple spinal cord monitoring to complicated intracranial brain function mapping.
We endeavor to staff beyond capacity for each region. We run a comprehensive on-call program throughout our organization. Therefore, we are able to cover weekend and evening cases. We are committed to meeting surgical monitoring needs whenever surgeries occur.
We feel that the quality of intraoperative neurophysiologic monitoring is enhanced through physician supervision. We therefore have developed a comprehensive network, which enables us to transmit the intraoperative monitoring information directly to any internet-enabled location. We employ a virtual private network, which assures uninterrupted connectivity. We can bring high-speed remote monitoring to any of our hospital and physician partners.
We bring together a comprehensive monitoring program including equipment and staff. The hospital needs only to supply the consumable items used during surgical monitoring such as EKG pads, disposable-needle electrodes, or specialty electrodes such as stimulating probes or cortical grids.
We require all of our staff to obtain the credentials appropriate to their activities. All clinical staff are required to obtain the certificate in intraoperative neurophysiological monitoring conferred by the American Board of Electrodiagnostic Technologists (ABRET). Masters level and Ph.D. staff are required to attain the diplomat credential from the American Board of Neurophysiological Monitoring (ABNM).
SSEPs have been shown to be very effective for monitoring the dorsal columns of the spinal cord. In general, manipulations of the spinal cord and ischemic events will usually affect dorsal column function. Thus, SSEPs correlate well with overall spinal cord function, but they do not indicate changes in the motor pathways. A number of cases have been reported in which motor evoked potentials showed changes while SSEPs remained unchanged.
We strongly recommend TcMEP monitoring for surgeries that involve significant manipulations or risk to the spinal cord. In particular, surgeries for correction of scoliosis, removal of spinal cord tumors or arteriovenous malformations, and thoracic spinal surgeries should be monitored using TcMEPs. TcMEPs could also be useful for any cervical spine surgery, particularly where there is myelopathy. TcMEPs have no demonstrated value for lumbar surgery.
TcMEPs recorded from muscle are significantly affected by the use of halogenated agents and nitrous oxide as well as the level of neuromuscular blockade. At a minimum alveolar concentration (MAC) of 1.0 or higher of the gases, TcMEPs are often unobtainable. We recommend low levels of gas (0.5 MAC of Halogenated Agent or 50 percent Nitrous oxide) supplemented with intravenous narcotics and propofol infusion. A neuromuscular blockade of at least 2/4 twitches is also minimally necessary. The ideal anesthetic would involve a total intravenous technique of narcotics, propofol, and benzodiazepine with no neuromuscular blockade.
Thousands of patients have been monitored safely using TcMEPs with very few complications. The primary safety concerns revolve around the stimulation of the patient’s cranium. Stimulation can cause significant movement of the patient’s head and neck muscles. Direct activation of the temporalis muscle and/or activation of the trigeminal nerve will cause a brief clenching of the jaw. Therefore, care will be taken to secure the patient’s tongue with a bite block or gauze pad in order to prevent laceration of the tongue. Patient movement at an inopportune time during the surgery can also create problems for the surgeon. Our neural monitoring technologists will alert you prior to any transcranial stimulation.
There is also some concern about the effect of stimulation on the brain. Our neural monitoring technologist will assess the risk factors preoperatively. These include: skull defects (burr holes, incomplete skull formation, deformity), intracranial metal implants (aneurysm clips, electrodes), pacemaker, and a history of seizures. The presence of any of these risk factors does not necessarily contraindicate the use of TcMEPs. Our protocol includes monitoring the patient’s EEG during the surgery for any evidence of seizure activity.
Given the right anesthetic conditions, a large majority of patients will have monitorable TcMEPs. Occasionally, a patient will not have evocable lower extremity or upper extremity TcMEPs. This may be due to technical factors (such as stimulus shunting through a thick scalp) or may be caused by poor spinal cord physiology. Once TcMEPs are obtained, however, the responses are very sensitive to changes in motor tract function.
We feel that the presence of reliable TcMEPs with no change in SSEPs makes the wake-up test unnecessary. The loss of TcMEPs or change in SSEPs, although, would warrant intervention, including possibly performing a wake-up test.
We require our neural monitoring technologists to obtain a signed consent form before proceeding with TcMEPs. Only the surgeon can authorize that this procedure be performed in the best interests of the patient without the consent form. There are no devices approved by the FDA for the application of transcranial stimulation.
Only the TcMEP can specifically monitor motor tracts. However, one alternative that can provide sensitive spinal cord monitoring is the descending evoked potential (DEP) to spinal cord stimulation. This technique was previously known as “neurogenic motor evoked potentials” or NMEP. That name has been discarded since it incorrectly implies a specific motor recording. DEPs involve rostral stimulation of the spinal cord with recording of a caudal neurogenic response from either the spinal cord or peripheral nerve, or a myogenic response recorded from a distal muscle. These responses can be mediated primarily by sensory pathways and therefore are not true motor potentials. Nevertheless, they have been proven to be sensitive to spinal cord changes, and may be useful for cases in which TcMEPs cannot be obtained.
If you have other questions about Biotronic, the modalities or monitoring services we offer, or would like our neural monitoring technologists to monitor a procedure at your hospital, contact us today.
812 Avis Drive
Ann Arbor, Michigan 48108
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Toll Free:
(866) 856-4404
Fax:
(734) 677-2423
If you have further questions about Biotronic or neurophysiologic intraoperative monitoring, contact us today.