*NEUROMONITORING [IONM] is a common term used to describe an evidence based patient care provided by Neurophysiologists with PhD/ M.D. The most appropriate term used to refer this medical health care field is Intra-Operative Neurophysiological Monitoring(IONM). *For consultancy use the contact/feedback form.
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Monday, October 5, 2009
ISIN-International Soceity of Intraoperative Neuromonitoring
Monday, August 24, 2009
NeuroMonitoring Cuts Stroke Risk of Carotid Surgery?
In this Elsevier medical news, Kerri writes about how utilizing neuromonitoring could cut the risks of stroke during carotid surgery, this is not a new report, but for those who missed this news article,
you can read it here.
Neuromonitoring Cuts Stroke Risk Of Carotid Surgery
BY KERRI WACHTER
Elsevier Global Medical News
ORLANDO — Targeted neuromonitoring can dramatically reduce stroke complications during and after carotid endarterectomy, according to one expert speaking at the annual meeting of the American Society of Neuroimaging. “A targeted monitoring strategy— and I stress the word targeted— has virtually eliminated intraoperative stroke and stroke due to postoperative carotid thrombosis in our unit,” said A. Ross Naylor, M.D., professor of vascular surgery at the University of Leicester in England. Carotid endarterectomy (CEA) carries a small but important
risk of stroke for both symptomatic and asymptomatic patients. Although neuromonitoring can be an effective way to minimize the risks associated with carotid endarterectomy,
here is “more to monitoring than deciding who needs a bit of plastic tubing shoved into their artery. You have to ask the right questions, and then you’ll start to get the right answers.” Dr. Naylor reported that his team uses continuous transcranial Doppler (TCD) sonography
and completion angioscopy for intraoperative monitoring. “We ask very limited questions
of transcranial Doppler,” he said. The group tries to maintain a mean middle cerebral artery velocity greater than 15 cm/sec. Hemodynamic failure is usually not the problem. “I have
seen over 1,200-1,500 carotids now in our unit, and I cannot ascribe hemodynamic failure to
any patient.” Technical errors and thrombosis are the more likely culprits. TCD reveals
shunt malfunctions and “is the only method capable of diagnosing on-table thrombosis,” he said.
Dr. Naylor and his team use ....
http://www.vascularweb.org/professionals/vascular_specialist/vol1/number1/pdf/VN_1005.pdf
Thursday, August 6, 2009
New on PubMed:
Investigation of the regeneration potential of the recurrent laryngeal nerve (RLN) after compression injury, using neuromonitoring.
Department of General and Visceral Surgery, Hospital of the Johannes Gutenberg-University Mainz, Langenbeckstr. 1, D-55131, Mainz, Germany. moskalenko@tut.by
INTRODUCTION:
The aim of this study was to investigate the regeneration potential of RLN after the compression of the nerve, without disrupting its continuity, using neuromonitoring.METHODS: In the first operation, the RLN and nervus vagus of adult Goettingen minipigs were dissected free, and the neuromonitoring parameters (amplitude, threshold and lag time of signal) were measured. Injury of the RLN was induced using a "bulldog" clamp. When the signal was no longer detectable, after the 15 min regeneration phase, the operation was finished. The neuromonitoring studies (see above) were repeated in a second operation 6 months later. RESULTS: (1) After the first operation, acute clamping of the RLN led to a reduction in the amplitude of the neuromonitoring signal; the lag time and the threshold of signal remained. Complete restitution of the signal was observed during the first regeneration phase. Repeated clamping led to complete disappearance of the signal. (2) During the second operation, i.e., after 6 months of regeneration, the neuromonitoring signals of both RLN and nervus vagus were detected in 93% of the GMP. No statistical differences (p = 0.17) were noticed between the amplitude of the RLN before the nerve injury (first operation) and after nerve regeneration (second operation). A significant increase in the lag time (p <>
PMID: 18751999 [PubMed - indexed for MEDLINE]
Wednesday, August 5, 2009
Nature Magazine and Review on Microscopy?
When I saw this news about "Nature Magazine's recent reviews on Microscopy,
I thought this is a good news for lots of readers and microscopy
specialists. I was thinking of writing about Microscopy and my personal
experiences in using various microscopes, good to know Nature carried out
this in the latest issue.
Out of the plethora of topics that I specialized during my graduation and research years, microscopy and tissue culture was one of them. I have been using microscopes ranging from a very basic compound microscope to dissection microcopes, bright field and phase contrast microscopes to microscopes with convulution set up, fluroscent microscope, TEM-Transmission Electron Microscope and 3D access Confocal Microscope...! I served as the editor of Connecticut Microscopy Society for a year and also helped in editorial for another year or so. This is just a honorary job and no support or financial help given, it is soley a interest in microscope based service to the society. For this service, I received Governors certificate of achievement and service from the Connecticut state Gov Jody Rell, my insterest in microscopy goes way back to school days and it is quite humbling to realize, sustained interest and practice leads to rewards and recognition. I will soon write more about microscopes.
For those who are interested to learn about the microcope and it's great use in
discovery, here is the Nature Journal editorial.
Nature Editorial:
Nature 459, 615 (4 June 2009) Microscopic marvels
Abstract
Microscopes are changing the face of biology. Researchers should innovate and collaborate if they want to be part of the new vision.
Watching molecular-scale events unfold in a living cell can be an inspiring experience. The inner workings of the nucleus, the shuttling of cellular cargo, the passage of messages through a membrane — seeing this tumultuous activity up close can fire the scientific imagination in a way that abstract data from genetic sequences or chemical analyses can never quite equal.
Friday, July 3, 2009
New: What's New in Spine Surgery?
In the following article "What's new in spine surgery, a perspective on latest approaches to treat cervical spinal deformity is discussed by Bridwell, KH et al, this is a very latest compilation of spine related works. At the bottom of this paper, the authors list some interesting recent works under the topic evidence based treatment in Orthopedic surgeries? in addition to their lengthy and useful reference list that will be of great interest to many.The Journal of Bone and Joint Surgery (American). 2009;91:1822-1834.
doi:10.2106/JBJS.I.00488
© 2009 The Journal of Bone and Joint Surgery, Inc.
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What's New in Spine Surgery
Many controversies still exist with regard to the surgical treatment of cervical spine pathology. The role of allograft, autograft, plate fixation, and bone morphogenetic protein is not entirely clear. There is still debate about the surgical treatment of myelopathy anteriorly as opposed to posteriorly. Clearly, there is substantial anatomic variation in the location of the vertebral artery. Disc arthroplasty for the cervical spine continues to appear to be a viable option for patients with single-level pathology.
Thursday, June 11, 2009
Hey, Watch your Back!!!, It is not just Swine Flu (H1N1) but much more dangerous HFMD is spreading in China?
Nature, the reputed UK based science magazine posted the following editorial about virus threat in China, oh wait it is not just about H1N1 which is spreading fast world wide. It is not even the SARS that the magazine is reporting about, but "Hand, Foot and Mouth Disorder (HFMD)?. How dangerous this HFMD.........read further!Editorial
Nature 459, 751-752 (11 June 2009) | doi:10.1038/459751b; Published online 10 June 2009
Watch your back
If you are a health official facing two highly contagious diseases — one that is already killing dozens of people, and another that threatens to kill people by the thousands or millions, but hasn't yet done so — how do you allocate your resources? The answer can be a difficult balancing act, as the situation in China is showing
In 2008, more than 500,000 HFMD infections were reported in China, and 200 people died. This year, as the disease moves through its peak season, similar numbers look possible. There is currently no vaccine to prevent it and no drug to cure it. The best safeguard is good hygiene: HFMD transmission is mainly via saliva and faeces. But even Singapore, renowned for its cleanliness, has had 8,896 cases this year, and had had even more by this time last year. There have also been cases this year in Taiwan, Hong Kong and South Korea.
Wednesday, June 10, 2009
Myelin Removal Beads....?
I received the following e-mail message about a new product related to myelin removal?. If you are looking for a better way to isolate and remove myelin.......'. I have not used this product or this companies antibody, just thought some one might benefit.
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Monday, June 1, 2009
Median Nerve SSEP:- Is there a relationship between Median Nerve SSEP & Level of Spinal Cord Injury?
The answer is yes, neuromonitoring of median nerve SSEPs conducted on 14 quadriplegic patients and 8 normal individuals. Amplitude and latency analysis of waveforms N9, N13 and N20 was conducted. N9 responses were present in all the patients and normal subjects, both amplitude and latency were similar in both groups.On the other hand, N13 was absent in Quadriplegia patients?
N20 was absent in C5 patients with Quadriplegia? but it was present in C6-7 patients, though the amplitudes were decreased with normal latency. Did you notice these waveform changes in your recording?.
Read further:
Original Article
Spinal Cord (2009) 47, 372–378; doi:10.1038/sc.2008.147; published online 20 January 2009
Relationship between median nerve somatosensory evoked potentials and spinal cord injury levels in patients with quadriplegia
M I F de Arruda Serra Gaspar1, A Cliquet Jr2,3, V M Fernandes Lima4 and D C C de Abreu1
Methods:
Fourteen individuals with quadriplegia and 8 healthy individuals were evaluated. Electrophysiological assessment of the median nerve was performed by evoked potential equipment. The injury level was obtained by ASIA. N9, N13 and N20 were analyzed based on the presence or absence of responses. The parameters used for analyzing these responses were the latency and the amplitude. Data were analyzed using mixed-effect models.
Thursday, May 7, 2009
Neuron News:-
Neuron news is a WebRing site that publishes some cool topics in neuroscience, in this Nov 2008 news note, they talk about EcoG and developments in this neurotechnology?. I do not find anything new in this news as EcoG is already recorded in clinical set up, but the one thing that is interesting in this news is the type of electrode development, something that can sit on the surface of the brain without perturbations of membranes or causing any penetration that would be deleterious, anyways, there are lots of stuff to browse through including a lot on consiousness at neuronews.
Wednesday, April 15, 2009
Lumbar Fusion & Analgesic related Death?
Mortality After Lumbar Fusion Surgery
Juratli, Sham Maghout MD, MPH; Mirza, Sohail K. MD, MPH; Fulton-Kehoe, Deborah PhD, MPH; Wickizer, Thomas M. PhD; Franklin, Gary M. MD, MPH
Abstract
Study Design. Retrospective population-based cohort study.
Objective. To describe mortality after lumbar fusion surgery in Washington State workers' compensation claimants in the perioperative period and beyond.
Summary of Background Data. Although lumbar fusion surgery can be associated with serious complications, perioperative mortality is generally considered rare. Population-based mortality estimates have been limited to surgery in older adults.
Methods. We identified all Washington State workers' compensation claimants who underwent fusion between January 1994 and December 2001 (n = 2378) and assessed the frequency, timing, and causes of death. Mortality follow-up was concluded in 2004. Death was ascertained from Washington State vital statistics records and from the workers' compensation claims database. Poisson regression was used to obtain age- and gender-adjusted mortality rates. Years of potential life lost, percent of potential life lost, and mean potential life lost were calculated for the leading 5 causes of death and we calculated the risk of death associated with selected predictors.
Results.
Among the 2378 lumbar fusion subjects in the study cohort, 103 were deceased by 2004. The 3-year cumulative mortality rate was 1.93% (95% confidence interval, 1.41%-2.57%). The 90-day perioperative mortality rate was 0.29% (95% confidence interval, 0.11%-0.60%). The risk of perioperative mortality was positively associated with repeat fusions. The age- and gender-adjusted all-cause mortality rate was 3.1 deaths per 1000 worker-years (95% confidence interval, 0.9-9.8).Analgesic-related deaths were responsible for 21% of all deaths and 31.4% of all potential life lost.
The risk of analgesic-related death was higher among workers who received instrumentation or intervertebral cage devices compared with recipients of bone-only fusions (1.1% vs. 0.0%; P = 0.03) and among workers with degenerative disc disease (age- and gender-adjusted mortality rate ratio, 2.71) (95% confidence interval, 1.17-6.28).The burden was especially high among subjects between 45 and 54 years old with degenerative disc disease (rate ratio, 7.45).
Conclusion. Analgesic-related deaths are responsible for more deaths and more potential life lost among workers who underwent lumbar fusion than any other cause. Risk of analgesic-related death was especially high among young and middle-aged workers with degenerative disc disease.
© 2009 Lippincott Williams & Wilkins, Inc.
Wednesday, March 4, 2009
Neurophysiological Monitoring Symposium!
What's New in Pediatric Orthopaedics???- Review by Kim and Noonan
andKenneth J. Noonan, MD published their reviews on"Pediatric Orthopaedics". They discuss about the recent advancements in the field of Pediatric Orthopadics with emphasis on various spine deformity, neurological disorders in childrens withappropirate surgical methods used. They have done an excellent review of the literature,the 82 references listed can be useful for those in the Pediatric Ortho as well as forNeurophysiologists. There is a section on basic science applications and in anothersection on spine, they talk about effectiveness of Intraoperative monitoring using motor evoked potentials.
Monday, February 16, 2009
Neuromonitoring:- a Review on PubMed Publications
We do not get much time to go read all the published papers on Neuromonitoring, unlike during the Laboratory research days, my visit to PubMed is less frequent, but yet I do not give up on my practice to go here and spend some time in catching up with the latest papers. In my recent visit to the PubMed, I found the following ongoing research activities in the field of neuromonitoring.
PubMed Search "Neuromonitoring" check the links direct to the articles.
Seder DB, Jarrah S argues that though Therapeutic Hypothermia (TH) is the most immediate and well known technique to review patients suffering from cardiac arrest (known as Encephalopathic survivors), a combined approach that involves various emerging tools such as critical care or Neuromonitoring can yield better outcome of patients, usage of neuromonitoring is critical during decooling phase...!In the same journal of Curr Treat Options Neurol, another article emphasize the knowledge and usage of multimodality neuromonitoring for better outcome of patients aneurysmal subarachnoid hemorrhage (SAH)
2.Critical care management of subarachnoid hemorrhage."This article reviews the natural history of aneurysmal SAH andstrategies for disease management in the acute setting, including available tools for monitoring brain function.Intensive care management of patients with SAH focuses on prevention of further neurologic injury. Aneurysmal rebleeding, hydrocephalus, seizures, and delayed ischemic injury represent major threats"
"Use of somatosensory evoked potentials (SEP) is the most widespread cerebral neuromonitoring during vascular surgery due to its high reliability and simple application. Sensitivity and specifity for ischemic lesions are 100% and 94%-99%, respectively. SEP are regarded as the gold standard for cerebral neuromonitoring in anaesthetized patients".
"Nerve monitoring decreased the incidence of transient but not permanent RLN paresis compared with visualization alone, particularly in high-risk patients".
"Intraoperative neuromonitoring (IONM) was used for RLN identification. Intact parathyroid hormone (iPTH) levels were determined early postoperatively at +6-h. Postoperative complications, conversion rate were analyzed. RESULTS: No cases required conversion to open surgery or ordinary recovery (i.e. >24h). Incidence of temporary hypoparathyroidism was 11.6% (5/43) with no case of symptomatic hypocalcemia. Incidence of temporary RLN injury was 2.3% (1 patient) with no case of permanent or bilateral RLN injury. All patients were satisfied with the type of recovery. CONCLUSIONS: This preliminary report is an example of the safe incorporation between new technologies (IONM, early iPTH measurement) with improvement of the quality and safety of VAT performed in a one-day surgery setting. (this is a Dec 2008 article, not 2009?)
"Inabnet WB, Murry T, Dhiman S, Aviv J, Lifante JC discuss that the dentification and preservation of the external branch of the superior laryngeal nerve (EBSLN) is paramount for normal vocal function preservation after thyroidectomy.Thyroidectomy was successfully completed under local anesthesia in all cases. The recurrent laryngeal nerve(s) was identified and preserved in each patient as demonstrated by normal perioperative transnasal flexible laryngoscopy.A total of 15 EBSLNs were at risk, but only 8 EBSLNs (53%) were definitively identified.Neuromonitoringdemonstrated preservation of the EBSLN in 100% of cases.The analysis of the results of the VHI-10 questionnaire before and 3 weeks after surgery indicated no significant change in patients' perception of voice severity. CONCLUSION:: Monitoring of the EBSLN during thyroidectomy under local anesthesia is a feasible alternative to conventional nerve monitoring under general anesthesia. This technique may be useful for the preservation of voice quality during a minimally invasive thyroidectomy under local anesthesia"
Friday, February 13, 2009
Human Atlas:- Video Education of Anatomy?
For someone who is just learning Anatomy or atlas of the Human body, this is a good place to start......... you can start here.
Audio and visual learning is more effective than just reading, though nothing can replace a careful and thorough reading habit. Modern tools makes learning much more easier and simpler.
Here it is, hope you will find it useful.
Saturday, January 24, 2009
Neurophysiology Recitation of Texts Only: 1824-1889?
it seems during early to late 1800's the Physiology was taught by reciting the texts. For the very first time live animal demonstration in anesthetized animals was introduced in America by Dalton.
Neurology 2000;55:859-864
© 2000 American Academy of Neurology
Historical Neurology
John Call Dalton, Jr., MD
America’s first neurophysiologist
From the Department of Veterans’ Affairs Medical Center and Department of Neurology (Dr. Fine and Ms. Manteghi), State University of New York at Buffalo; Finger Lakes Radiation Oncology (Dr. Sobel), Clifton Springs, NY; and the Robert L. Brown, MD, History of Medicine Collection (Ms. Lohr), State University at Buffalo, NY.
Address correspondence and reprint requests to Dr. Edward J. Fine, Neurology Service, Department of Veterans’ Affairs Medical Center, 3495 Bailey Avenue, Buffalo, NY 14215.
Before the discoveries of John Call Dalton, Jr., MD (1824–1889), innervation of laryngeal muscles, long-term effects of cerebellar lesions, and consequences of raised intracranial pressure were poorly understood. Dalton discovered that the posterior cricoarytenoid muscles adducted the vocal cords during inspiration. He confirmed Flourens’ observations that acute ablation of the cerebellum of pigeons caused loss of coordination. Dalton observed that properly cared for pigeons gradually recovered "coordinating power." Dalton observed that prolonged raised intracranial pressure caused tachycardia and then fatal bradycardia in dogs. Before Dalton published his photographic atlas of the human brain, neuroanatomy atlases were sketched by Europeans and imported into the United States. Dalton’s atlas of the human brain contained precise photographs of vertical and horizontal sections that equal modern works. Before Dalton introduced live demonstrations of animals, physiology was taught by recitation of texts only. Dalton was the first American-born professor to teach physiology employing demonstrations of live animals operated on under ether anesthesia. He wrote an essay advocating experimentation on animals as the proper method of acquiring knowledge of function and that humane animal experimentation would ultimately improve the health of man and animals. His eloquent advocacy for humane experimental physiology quelled attacks by contemporaneous antivivisectionists. Dalton was America’s first experimental neurophysiologist.
73% of Patients suffered Complications, 11 out of 15 Patient?, What kind of IONM Company serves such a Surgeon?
Today's "Daily Record" carried the following news about a"medical malpractice suit"filed against Northwest Medical Center. In addition to the hospital and the surgeon, the neuromonitoring company known as American Intraoperative Monitoring LLC? is also in trouble?.
"If" one has to go by this report and the number of surgeries done by the surgeon involved in this suit, 11 out of 15 patients (73%) had complications after spinal corrections (it not clear what kind of surgical procedure done on all the 15 surgical procedures, but the current case that is reported here is an anterior discectomy and fusion simply known as ACDF?). The number of patients suffering from post surgical complications are very significant, going by this report. This amount of surgical complications in the first place is rare, I haven't heard of a 73% complications (unless someone send me some past reports or ref?).
Nevertheless, for argument I am wondering, what kind of a Neuromonitoring Company will provide neurophyisological monitoring services to a surgeon of this kind reported in this law suit?. Why?. Are you part of a bad practice and demoralized medical ethics, do you know what you are doing inside the OR?.
The report also claims that the Neuromonitoring Staff, seems to be an RN trained in neuromonitoring was aware about abnormalities (?? is this SSEPs loss? or Motor Loss or Spinal cord damage or what?) but did not warn the surgeon while it was happening during the surgery, neither he or she reported this after the surgical procedure?............Immmmmm...?
Northwest Medical Center added to malpractice suit
By Scott F. Davis Northwest Arkansas Times
Posted on Friday, January 23, 2009
Email this story | Printer-friendly version
FAYETTEVILLE - A Bentonville couple amended their malpractice lawsuit Thursday against Dr. Cyril "Tony" Anthony Raben and his clinic, Northwest Arkansas Spine and Orthopedic Associates, adding three new parties as defendants.
Theresa Paulino and her husband, Eddie Paulino, seek damages because she lost the use of her legs following neck surgery by Raben on Dec. 17, 2008, according to the complaint.
The Paulinos added Northwest Medical Center to the lawsuit, claiming "negligent credentialing" after learning that an audit by the Arkansas State Medical Board showed a very high complication rate for Raben's prior surgeries.
Read the full story: click the topic of this news linked to the original news.
Sunday, January 4, 2009
Dexmedetomidine- A New Short Term Sedative?
Dexmedetomidine: a novel sedative-analgesic agent Ralph Gertler, MD,1 H. Cleighton Brown, MD,1 Donald H. Mitchell, MD,1 and Erin N. Silvius, MD1 1From the Department of Anesthesiology and Pain Management, Baylor University Medical Center, Dallas, Texas; and Department of Anesthesiology and Pain Management, The University of Texas Southwestern Medical Center at Dallas. Corresponding author. Corresponding author: Ralph Gertler, MD, Department of Anesthesiology and Pain Management, Baylor University Medical Center, 3500 Gaston Avenue, Dallas, Texas 75246 (e-mail: Ralph_Gertler10@excite.com).
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Neuromonitoring & Peadiatric Cardiopulmonary bypass surgical procedures?:- Boosts Evidence Based practice & Best Practice?
Usage of intraoperative neurophysiologic monitoring during Peadiatric cardiopulmonary bypass surgical procedures reported in the following research papers, addition of IONM tothe surgical team has helped them to improve the post surgical neurological complications. Two of the following studies one published recently in Sept-Oct 2008 and the other in 2007, both in peer reveiwed journals discuss the importance of IONM usage in terms of reducing neurological risk, patient safety and faster discharge of patients that could be benefitial to both the patients and the hospitals.
The influence of neurophysiologic monitoring on the management of pediatric cardiopulmonary bypass.
Department of Anesthesiology, Penn State College of Medicine, Hershey, Pennsylvania 17033, USA. skimatian@hmc.psu.edu
We describe a process by which we sought to determine how the addition of intraoperative neurophysiologic monitoring (IONM) impacted the management of cardiopulmonary bypass (CPB) during pediatric cardiac surgery.While maintaining a consistent team of surgeons, anesthesiologists, nurses, and perfusionists, a multi-modal, IONM program was established consisting of Near Infrared Spectroscopy, Transcranial Doppler, and eight channel electroencephalography. A retrospective review of cases from 1 year before the institution of the IONM program was compared with data obtained from cases performed after neurophysiologic monitoring was established as a standard of care for pediatric patients on CPB.
This comparative analysis of CPB management revealed a significant increase in the use of donor blood added to the CPB circuit prime as well as in the maintenance of a higher hematocrit during the bypass period after the implementation of IONM.These changes in the management of pediatric CPB correlated with recommendations of previous studies that examined postoperative neurophysiologic outcomes, suggesting that these changes were not only consistent with best practices, but that the presence of IONM data facilitated a transition to evidence-based practice.
Benefit of neurophysiologic monitoring for pediatric cardiac surgery.
Department of Surgery, University of Louisville School of Medicine, Ky., USA.
BACKGROUND: Pediatric patients undergoing repair of congenital cardiac abnormalities have a significant risk of an adverse neurologic event. Therefore this retrospective cohort study examined the potential benefit of interventions based on intraoperative neurophysiologic monitoring in decreasing both postoperative neurologic sequelae and length of hospital stay as a cost proxy.
METHODS: With informed parental consent approved by the institutional review board,
electroencephalography, transcranial Doppler ultrasonic measurement of middle cerebral artery blood flow velocity, and transcranial near-infrared cerebral oximetry were monitored in 250 patients.An interventional algorithm was used to detect and correct specific deficiencies in cerebral perfusion or oxygenation or to increase cerebral tolerance to ischemia or hypoxia. RESULTS: Noteworthy changes in brain perfusion or metabolism were observed in 176 of 250 (70%) patients. Intervention that altered patient management was initially deemed appropriate in 130 of 176 (74%) patients with neurophysiologic changes.
Obvious neurologic sequelae (i.e., seizure, movement, vision or speech disorder) occurred in five of 74 (7%) patients without noteworthy change, seven of 130 (6%) patients with intervention, and 12 of 46 (26%) patients without intervention (p = 0.001). Survivors' median length of stay was 6 days in the no-change and intervention groups but 9 days in the no-intervention group. In addition, the percentage of patients in the no-intervention group discharged from the hospital within 1 week (32%) was significantly less than that in either the intervention (51%, p = 0.05) or no-change (58%, p = 0.01) groups.On the basis of an estimated hospital neurologic complication cost of $1500 per day, break-even analysis justified a hospital expenditure for neurophysiologic monitoring of $2142 per case. CONCLUSIONS:
Interventions based on neurophysiologic monitoring appear to decrease the incidence of postoperative neurologic sequelae and reduce the length of stay. Inasmuch as the break-even cost for neurophysiologic monitoring is more than four times the actual average charge, both patients and hospital may profit from this service.Because this study was not a truly randomized clinical trial, unintentional statistical bias may have occurred and caution is urged in interpreting the magnitude of apparent intergroup outcome differences.