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Dive into the research topics where Iain H. Kalfas is active.

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Featured researches published by Iain H. Kalfas.


Anesthesiology | 2000

Relation between perioperative hypertension and intracranial hemorrhage after craniotomy.

Ayman Basali; Edward J. Mascha; Iain H. Kalfas; Armin Schubert

Background Previous data suggest that systemic hypertension (HTN) is a risk factor for postcraniotomy intracranial hemorrhage (ICH). The authors examined the relation between perioperative blood pressure elevation and postoperative ICH using a retrospective case control design. Methods The hospital’s database of all patients undergoing craniotomy from 1976 to 1992 was screened. Coagulopathic and unmatchable patients were excluded. There were 69 evaluable patients who developed ICH postoperatively (n = 69). A 2-to-1 matched (by age, date of surgery, pathologic diagnosis, surgical procedure, and surgeon) control group without postoperative ICH was assembled (n = 138). Preoperative, intraoperative, and postoperative blood pressure records (up to 12 h) were examined. Incidence of perioperative HTN (blood pressure ≥ 160/90 mmHg) and odds ratios for ICH were determined. Results Of the 11,214 craniotomy patients, 86 (0.77%) suffered ICH, and 69 fulfilled inclusion criteria. The incidence of preoperative HTN was similar in the ICH (34%) and the control (24%) groups. ICH occurred 21 h (median) postoperatively, with an interquartile range of 4–52 h. Sixty-two percent of ICH patients had intraoperative HTN, compared with only 34% of controls (P < 0.001). Sixty-two percent of the ICH patients had prehemorrhage HTN in the initial 12 postoperative hours versus 25% of controls (P < 0.001), with an odds ratio of 4.6 (P < 0.001) for postoperative ICH. Hospital stay (median, 24.5 vs. 11.0 days), and mortality (18.2 vs. 1.6%) were significantly greater in the ICH than in the control groups. Conclusions ICH after craniotomy is associated with severely prolonged hospital stay and mortality. Acute blood pressure elevations occur frequently prior to postcraniotomy ICH. Patients who develop postcraniotomy ICH are more likely to be hypertensive in the intraoperative and early postoperative periods.


Neurosurgery | 1988

Postoperative hemorrhage: a survey of 4992 intracranial procedures

Iain H. Kalfas; John R. Little

A series of 4992 intracranial procedures performed over an 11-year period was evaluated for the occurrence of postoperative hemorrhage. Forty patients (0.8%) experienced postoperative hemorrhage. Twenty-four hemorrhages were intracerebral (60%), 11 were epidural (28%), 3 were subdural (7.5%), and 2 were intrasellar (5.0%). Hematomas in 33 patients occurred at the operative site, and 7 occurred remote from the operative site. Intracranial tumor was the reason for operation in 56% of the patients developing a clot, and meningioma was the most common tumor associated with this complication. The use of the sitting position was not associated with an increased incidence of postoperative hemorrhage. Disturbances of coagulation and hypertension seemed to be potential precipitating factors. Postoperative hemorrhage was recognized within 12 hours of operation in 35% of the patients. An altered level of consciousness was the most frequent clinical finding, present in all patients. There was no clear relationship between the time of recognition and the final clinical outcome. Parenchymal clots carried the worst prognosis, accounting for 8 of the 11 deaths and all 7 patients with poor neurological outcome.


Spine | 2004

Spinal Surgery in patients with Parkinson's disease: Construct failure and progressive deformity

L. Brett Babat; Robert F. McLain; William Bingaman; Iain H. Kalfas; Phillip Young; Candace Rufo-Smith

Study Design. Retrospective case series review of patients with Parkinson’s disease undergoing elective spine surgery at a single tertiary referral center. Objectives. To assess the rate of complications of spine surgery in the population with Parkinson’s disease and characterize the causes of failure and special needs of this unique population. Summary of Background Data. Patients with Parkinson’s disease experience a combination of poor bone quality and a severe neuromuscular disorder. There is little information in the literature about outcomes of spine surgery in this population. Preliminary review suggests that these patients have a high rate of instrument-related complications that has not been reported previously. Methods. A computerized search using diagnostic and procedural codes identified 14 patients with Parkinson’s disease who underwent spine surgery from January 1993 through December 2000. Their charts and radiographs were reviewed, and those not examined within twelve months were invited for follow-up review. The remaining patients were being followed on a regular basis by their spine surgeon, the Movement Disorders Clinic, or both and were seen and examined during their routine follow-up observation. Indications and Extent of Index Surgery Varied. Complications, revisions, and radiographic evidence of loosening were assessed. Causes of failure were sought with respect to surgical and clinical factors. All patients underwent surgical care by a fellowship-trained spine surgeon. Results. The mean follow-up period from index procedure was 66.8 months; the median follow-up period was 38 months. Of 14 patients, 12 (86%) required additional surgery, undergoing a total of 31 reoperations. Eleven patients (79%) underwent 22 additional procedures at the same or adjacent level for instability, including four patients (29%) who had hardware failure or pullout, necessitating 10 reoperations. The one other patient who required additional surgery had a successful index procedure but underwent another operation to address instability at a remote spinal segment. Of five patients whose index procedure involved only one spinal level, three (60%) required additional procedures, all at that level. Two patients (14%) developed wound infections during the course of treatment but not as the cause of initial treatment failure. The primary mechanisms of failure were relentless kyphosis or segmental instability at the operated-on or adjacent levels. Conclusion. Patients with Parkinson’s disease undergoing spine surgery in a single tertiary referral center had a very high reoperation rate associated with technical complications. Patients should be appropriately counseled regarding the increased risk of operative complications and closely followed for incipient failure.


Neurosurgery | 1989

Intracranial Meningiomas in the Aged: Surgical Outcome in the Era of Computed Tomography

Issam A. Awad; Iain H. Kalfas; Joseph F. Hahn; John R. Little

Seventy-five patients older than 60 years of age underwent surgical resection of intracranial meningiomas during a 10-year period at a single institution. All patients had a computed tomographic scan preoperatively, and all were followed for at least 3 months postoperatively. There were 50 patients 61 to 70 years of age (Group A), and 25 patients older than 70 years (Group B). Sixteen patients (21%) were asymptomatic, and no patient was severely disabled preoperatively. Operative morbidity and mortality and outcome at 3 months were assessed and correlated with age, preoperative neurological status, and tumor size and location. Operative mortality was 6.6% (6% in Group A; 8% in Group B). Perioperative morbidity (including medical and surgical complications and worsening in neurological status) was 48% (46% in Group A; 52% in Group B). Neurological status 3 months after surgery was improved by at least one grade as compared to before surgery in 40% of patients (38% in Group A; 44% in Group B), unchanged in 29% (34% in Group A; 20% in Group B), and worsened in 31% (28% in Group A; 36% in Group B). While nearly half of the patients were asymptomatic 3 months after surgery, 11 patients (15%) had died or remained seriously disabled. Outcome at 3 months correlated significantly with low neurological grade preoperatively and with a tumor location over the cortical convexity. There was no significant correlation with age or tumor size. We conclude that resection of intracranial meningiomas is associated with significant morbidity and mortality in the elderly.(ABSTRACT TRUNCATED AT 250 WORDS)


Neurosurgery | 1994

Changes in the cervical foraminal area after anterior discectomy with and without a graft

Michael A. Murphy; Mary Beth Trimble; Marion R. Piedmonte; Iain H. Kalfas

A controversial point in the management of patients undergoing anterior cervical discectomy is whether an interbody bone graft should be used. Proponents of interbody grafting claim that without a graft, the disc height and the area of the foramina at that level will decrease postoperatively with the potential for persistent symptoms and/or the development of a radiculopathy. Using a two-dimensional digital planimeter, we measured the cross-sectional area (cm2) of cervical foramina on preoperative and postoperative oblique films in patients undergoing anterior cervical discectomy. Group A patients underwent the insertion of an interbody graft after the discectomy; Group B patients did not. Our results indicate that in all the patients in Group A, there was a statistically significant increase in the area of the foramina (P < 0.001) and in Group B, a statistically significant decrease (P = 0.0005). However, when the absolute change in magnitude of the foramina was measured, without respect to an increase or decrease, there was no statistically significant difference (P > 0.8). There was no statistically significant difference (P = 1.000) in the outcome between the two groups. From an anatomical standpoint, our data support the insertion of an interbody graft if the surgeon wishes to increase the area of the foramen. However, the overall magnitude of change is not significant, which may be a factor in why the clinical outcome is similar in both groups.


Neurosurgery | 1995

Antibiotic Penetration into Cervical Discs

R. L. Patrick Rhoten; Michael A. Murphy; Iain H. Kalfas; Joseph F. Hahn; John A. Washington

Antibiotics are frequently prophylactically administered in surgical procedures to reduce the incidence of infection. The penetration of antibiotics into lumbar discs has been studied with mixed results, but penetration into cervical discs has not been reviewed. In this study, we examined the penetration of two commonly used antibiotics, oxacillin and cefazolin, into cervical discs. Eighteen patients with a total of 30 discs removed were studied. Two groups, each consisting of four patients with five discs removed, received either 1 g of oxacillin or 1 g of cefazolin by a single, preoperative intravenous infusion. Two other groups, each consisting of five patients with 10 discs removed, received either 2 g of oxacillin or 2 g of cefazolin, also by a single, preoperative intravenous infusion. A blood specimen, from which serum antibiotic levels were determined, was obtained from each patient simultaneously with each discectomy. The time interval between the antibiotic infusion and discectomy/phlebotomy was also recorded. Antibiotic levels were detected in all discs removed but were quantifiable in only 12. Nine of these 12 had been exposed to cefazolin. Of these nine discs, one was from a patient who had received 1 g whereas the other eight were from patients who had received 2 g of cefazolin. This represents 80% of the removed discs exposed to 2 g of cefazolin (10 discs total) and 20% exposed to 1 g (5 discs total). The remaining three discs with quantifiable antibiotic levels had been exposed to 2 g of oxacillin, which represents 30% of the discs (10 total) exposed to that dose of oxacillin. Although cervical disc space infections are rare, they are serious.(ABSTRACT TRUNCATED AT 250 WORDS)


Spine | 2004

Complications associated with lumbar laminectomy: a comparison of spinal versus general anesthesia.

Robert F. McLain; Gordon R. Bell; Iain H. Kalfas; John E. Tetzlaff; Helen J. Yoon

Study Design. A case-controlled, comparative study of 400 patients undergoing lumbar surgery, treated with either spinal or general anesthesia. An independent observer analyzed outcomes. Objectives. To determine the rate and type, of perioperative complications associated with each anesthetic method among lumbar surgery patients. Summary of Background Data. Spinal anesthesia is infrequently used for spinal procedures. While complications associated with spinal anesthesia are rare, some authors have suggested that spinal anesthesia may exacerbate existing neurologic disease and have recommended against its use in lumbar disc surgery. Others have found the technique safe and effective. General anesthesia may be preferred because it is seen as the routine accepted practice, because of greater patient acceptance and the ability to perform longer operations, or because of a general sense that general anesthesia is “safer” in these procedures. Methods. Patients treated between 1994 and 1998 were matched for anesthetic class, preoperative diagnosis, surgical procedure, and perioperative protocols. All patients were treated according to a uniform protocol and recovered in the same perianesthetic environment. Data from the intraoperative period through hospital discharge were collected and compared. Results. A total of 200 patients were included in each group. Overall complication rates and time to discharge were significantly lower in spinal anesthetic patients. Total anesthetic and operative times were significantly longer for general anesthetic patients, and perioperative heart rate and mean arterial pressures were elevated compared with those in spinal anesthetic patients. Nausea, requirements for antiemetic medication, and the incidence of urinary retention were significantly increased among general anesthesia patients. Spinal anesthesia patients had fewer spinal headaches compared with the general anesthetic group, but statistical significance was not obtained. Conclusions. For patients undergoing decompressive lumbar surgery, spinal anesthesia is at least comparable to general anesthetic with respect to complications. Specific advantages to spinal anesthesia include decreased nausea and antiemetic requirements, reduced analgesic requirements, and reduced overall complication rate.


Journal of Neurosurgery | 2011

The role of adjuvant radiation therapy in the treatment of spinal myxopapillary ependymomas

Samuel T. Chao; Taisei Kobayashi; Edward C. Benzel; C.A. Reddy; Glen Stevens; Richard A. Prayson; Iain H. Kalfas; Richard Schlenk; Ajit A. Krishnaney; Michael P. Steinmetz; William Bingaman; Joseph F. Hahn; John H. Suh

OBJECT the goal in this study was to determine the role of radiation therapy (RT) in the treatment of spinal myxopapillary ependymomas (MPEs). METHODS thirty-seven patients with histologically verified spinal MPEs were reviewed. Kaplan-Meier analyses and Cox proportional hazard regression were used to determine what patient and treatment factors influenced overall survival (OS) and recurrence. RESULTS at the time of initial diagnosis, the median age was 33 years and the Karnofsky Performance Scale score was 80. In 86.5% of cases, the most common presenting symptom was pain. All patients received surgery as their initial treatment. Nine patients also received RT along with surgery, with a median total dose of 50.2 Gy. The mean survival time was 12.2 years; however, only 4 of 37 patients had died at the time of this study. None of the patient or treatment parameters significantly correlated with OS. Sixteen patients (43.2%) were found to have a recurrence, with a median time to recurrence of 7.7 years. None of the patient or treatment parameters correlated with recurrence-free survival for an initial recurrence. The median time to the second recurrence (recurrence following therapy for initial recurrence) was 1.6 years. Use of RT as salvage therapy after initial recurrence significantly correlated with longer times to a second recurrence. The median recurrence-free survival time before the second recurrence was 9.6 years for those who received RT versus 1.1 years for those who did not receive RT (p = 0.0093). None of the other parameters significantly correlated with a second recurrence. CONCLUSIONS radiation therapy may have a role as salvage therapy in delaying recurrences of spinal MPEs.


Journal of Neurosurgical Anesthesiology | 2008

Patient-controlled epidural analgesia (PCEA) for postoperative pain control after lumbar spine surgery.

Juan P. Cata; Edward Noguera; Emily Parke; Zeyd Ebrahim; Andrea Kurz; Iain H. Kalfas; Edward J. Mascha; Ehab Farag

Spine surgery remains one of the most common procedures for patients with a wide variety of spine disorders. Postoperative pain after major spine surgery is moderate to severe. We retrospectively reviewed 245 medical records of adult patients undergoing major spine surgery who received either patient-controlled epidural analgesia based on local anesthetics and opioids or patient-controlled intravenous analgesia as postoperative pain management. Several outcomes were analyzed including pain intensity, opioid consumption, time to endotracheal extubation, the incidence of deep venous thrombosis, and length of stay in the hospital. We found that the use of patient-controlled epidural analgesia provided better postoperative analgesia [median (quartiles) verbal analog scale score of 4 (3, 5) vs. 5 (3, 6)] and decreased the amount of opioid consumption postoperatively [median of 0 mg (0, 3) vs. 35 mg (0, 150)] compared with patient-controlled intravenous analgesia. Also, a substantially higher number of patients in the patient-controlled intravenous group required opioids as rescue analgesia. Incidences of deep venous thrombosis, operating room extubation, and length of stay in the hospital were not associated with the analgesic technique. The results of this study suggest that the use of neuroaxial analgesia for the management of postoperative pain associated with major spine surgery may have some beneficial properties over intravenous analgesia. The use of a reduced amount of opioids by patients with epidural analgesia may be relevant because of potential fewer side effects mainly in elderly patients. Several limitations related to the retrospective nature of the study are described. Prospective randomized-controlled trials are needed to understand and elucidate the optimum regimen of postoperative pain management after major spine surgery.


Journal of Neurosurgery | 2008

A review of the utility of obtaining repeated postoperative radiographs following single-level anterior cervical decompression, fusion, and plate placement

Kene Ugokwe; Iain H. Kalfas; Thomas E. Mroz; Michael P. Steinmetz

OBJECT Pseudarthrosis and construct failure following single-level anterior cervical discectomy, fusion, and plate placement (ACDFP) rarely occur. Routine postoperative anteroposterior and lateral radiographs may be an inconvenience to patients and expose them to additional and potentially unnecessary radiation. No standard exists to define when patients should obtain radiographs following an ACDFP. The authors hypothesize that routinely obtaining static anteroposterior and lateral radiographs in patients who recently underwent a single-level ACDFP without new axial neck pain or other neurological complaints or symptoms is unwarranted and does not alter the long-term treatment of the patient. METHODS The authors retrospectively reviewed the charts and radiographs of patients who underwent a single-level ACDFP between January 1, 2000, and December 31, 2005. All patients underwent a single-level ACDFP and had routine cervical radiographs obtained at various intervals after surgery. RESULTS Twenty-one patients underwent ACDFP at C5-6, 14 patients underwent surgery at C6-7, 11 patients at C4-5, and 7 patients at C3-4. None of the intraoperative radiographs demonstrated malposition of the graft or instrumentation. Based on subjective reporting by the patients, the vast majority (49 of 53) showed improvement in neck and arm pain, and/or neurological dysfunction following surgery. Overall, 5 patients (9%) demonstrated abnormalities on their postoperative radiographs. No patients were returned to the operating room as a result of postoperative radiographic findings. The sensitivity of plain radiographs in this patient series or the percentage of patients with new symptoms that had an abnormality related to the construct on plain radiography was 50%. The specificity of plain radiographs or the percentage of patients who were asymptomatic and had normal radiographs was 94%. The positive predictive value was 25%; that is, there was a 25% chance that patients with symptoms would have a construct abnormality on postoperative radiographs. The negative predictive value was 98%; that is, 98% of patients without symptoms will have normal radiographs. CONCLUSIONS Pseudarthrosis and construct failure following single-level ACDFP occur rarely, and patients with new symptoms following surgery are as likely to have normal radiographic findings as they are to have abnormalities identified on their postoperative plain radiographs. Routinely obtaining postoperative radiographs at regular intervals in asymptomatic patients following single-level ACDFP does not appear to be warranted.

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