Panayiotis N. Varelas
Johns Hopkins University
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Critical Care Medicine | 2003
Wendy C. Ziai; Panayiotis N. Varelas; Scott L. Zeger; Marek A. Mirski; John A. Ulatowski
ObjectiveGreater demand and limited resources for intensive care monitoring for patients with neurologic disease may change patterns of intensive care unit utilization. The necessity and duration of intensive care unit management for all neurosurgical patients after brain tumor resection are not clear. This study evaluates a) the preoperative and perioperative variables predictive of extended need for intensive care unit monitoring (>1 day); and b) the type and timing of intensive care unit resources in patients for whom less intensive postoperative monitoring may be feasible. DesignRetrospective chart review. SettingA neurocritical care unit of a university teaching hospital. PatientsPatients were 158 consecutive postoperative brain tumor resection patients admitted to a neurocritical care unit within a 1-yr period (1998–1999). InterventionsNone. Measurements and Main ResultsTwenty-three patients (15%) admitted to the neurocritical care unit for >24 hrs were compared with 135 (85%) patients admitted for <24 hrs. Predictors of >1-day stay in the neurocritical care unit in a logistic regression model were a tumor severity index comprising radiologic characteristics of tumor location, mass effect, and midline shift on the preoperative magnetic resonance imaging scan (odds ratio, 12.5; 95% confidence interval, 3.1–50.5); an intraoperative fluid score comprising estimated blood loss, total volume of crystalloid, and other colloid/hypertonic solutions administered (odds ratio, 1.8; 95% confidence interval, 1.2–2.6); and postoperative intubation (odds ratio, 67.5; 95% confidence interval, 6.5–702.0). Area under the receiver operating characteristic curve for the model of independent predictors for staying >1 day in the neurocritical care unit was 0.91. Neurocritical care unit resource use was reviewed in detail for 134 of 135 patients who stayed in the neurocritical care unit for <1 day. Sixty-five (49%) patients required no interventions beyond postanesthetic care and frequent neurologic exams. A total of 226 intensive care unit interventions were performed (mean ± sd, 1.7 ± 2.6) in 69 (51%) patients. Ninety (67%) patients had no further interventions after the first 4 hrs. Neurocritical care unit resource use beyond 4 hrs, largely consisting of intravenous analgesic use (72% of orders), was significantly associated with female gender, benign tumor on frozen section biopsy, and postoperative intubation (chi-square, p < .05). ConclusionsA small fraction of patients require prolonged intensive care unit stay after craniotomy for tumor resection. A patient’s risk of prolonged stay can be well predicted by certain radiologic findings, large intraoperative blood loss, fluid requirements, and the decision to keep the patient intubated at the end of surgery. Of those patients requiring intensive care unit resources beyond the first 4 hrs, the interventions may not be critical in nature. A prospective outcome study is required to determine feasibility, cost, and outcome of patients cared for in extended recovery and then transferred to a skilled nursing ward.
Journal of Neurosurgical Anesthesiology | 2001
Panayiotis N. Varelas; Marek A. Mirski
Seizures are a common occurrence in the intensive care unit (ICU). The presentation of seizures is usually as focal or generalized motor convulsions, but other seizure types may occur. Etiologies of the seizures are typically secondary either to primary neurologic pathology or a consequence of critical illness and clinical management. Particularly important as precipitants of seizures are hypoxia/ischemia, drug toxicity, and metabolic abnormalities. It is important to properly diagnose the seizure type and its cause to ensure appropriate therapy. Most seizures occur singly, and recurrence is usually prevented with initiation of anticonvulsant therapy. However, status epilepticus may develop, which requires emergent treatment before irreversible brain injury occurs. Treatment with anticonvulsants is not without untoward risks, however, and primary toxicities of these agents is reviewed. After traumatic head injury, brain surgery, or cerebrovascular accidents, many patients are at risk for seizures. Current data on the benefits of prophylactic therapy for such patients is also reviewed.
Neurocritical Care | 2006
Antigone Triantafyllopoulou; Andrew Beaumont; John A. Ulatowski; Rafael J. Tamargo; Panayiotis N. Varelas
IntroductionAcute subdural hematoma (SDH) is an infrequent complication after aneurysmal subarachnoid hemorrhage. SDH associated with unruputed intracavernous aneurysm has never been reported.MethodsSingle patient case report and review of relevent literature.ResultsA 65-year-old woman with an unruptured, thrombosed giant intracavernous aneurysm developed an acute SDH 2 days after admission for cavernous sinus syndrome. Despite emergent evacuation of the SDH, the patient never regained consciousness because of brain herniation.ConclusionAcute SDH is a rare complication of ruptured, giant intracavernous aneurysms. Erosion of the cavernous sinus wall by acute enlargement of the aneurysm after thrombosis is the proposed mechanism for development of the SDH.
Cerebrovascular Diseases | 2001
Christine A.C. Wijman; Nichol McBee; Penelope M. Keyl; Panayiotis N. Varelas; Michael A. Williams; John A. Ulatowski; Daniel F. Hanley; Robert J. Wityk; Alexander Y. Razumovsky
Objective: The impact of early transcranial Doppler ultrasonography (TCD) upon stroke subtype diagnosis is unknown and may affect therapeutic strategies. In this study, the diagnostic usefulness of TCD in stroke subtype diagnosis according to the criteria of the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) study was investigated in patients with acute cerebral ischemia. Methods: TCD examination within 24 h of symptom onset was performed in 50 consecutive patients with acute cerebral ischemia. Of these 54% were female. Sixty percent of patients were black, 36% white, and 4% Asian. Initial TOAST stroke subtype diagnosis (ITSSD) was based upon clinical presentation and initial brain imaging studies. Modified TOAST stroke subtype diagnosis was determined subsequently after additional review of the TCD examination. Final TOAST stroke subtype diagnosis was determined at hospital discharge, incorporating all diagnostic studies. Using final TOAST stroke subtype diagnosis as the ‘gold standard’ ITSSD and modified TOAST stroke subtype diagnosis were compared in order to determine additional benefit from the information obtained by TCD. Data were collected retrospectively by a single investigator. Results: ITSSD classified 23 of 50 (46%) patients correctly. After TCD, 30 of 50 (60%) patients were classified correctly, for an absolute benefit of 14% and a relative benefit of 30% (p = 0.018). Most benefit from TCD was observed in the TOAST stroke subtype category large-artery atherosclerosis, in particular in patients with intracranial vascular disease. In this category, ITSSD had a sensitivity of 27% which increased to 64% after TCD (p = 0.002). Conclusion: TCD within 24 h of symptom onset improves the accuracy of early stroke subtype diagnosis in patients with acute cerebral ischemia due to large-artery atherosclerosis. This may have clinical implications for early therapeutic interventions.
Cerebrovascular Diseases | 2001
Julien Bogousslavsky; Jacques R. Leclerc; R.B. Libman; T.G. Kwiatkowski; M.D. Hansen; W.R. Clarke; R.F. Woolson; H.P. Adams; J.M. de Bray; A. Pasco; F. Tranquart; X. Papon; C. Alecu; B. Giraudeau; F. Dubas; J. Emile; Josef Finsterer; Andrea Kladosek; Doris Lubec; Herbert Auer; Eivind Berge; Hild Fjærtoft; Bent Indredavik; Per Morten Sandset; Panayiotis N. Varelas; Michael A. Williams; John A. Ulatowski; Daniel F. Hanley; Robert J. Wityk; Alexander Y. Razumovsky
s of the 6th Meeting of the European Society of Neurosonology and Cerebral Hemodynamics, and of the 9th Meeting of the Neurosonology Research Group of the World Federation of Neurology Lisbon, Portugal, May 13–15, 2001 Editors: Oliveira, V. (Lisbon); Azevedo, E. (Porto); Russell, D. (Oslo)
Neurosurgical Focus | 2007
Romergryko G. Geocadin; Panayiotis N. Varelas; Daniele Rigamonti; Michael A. Williams
The Neurologist | 1999
Panayiotis N. Varelas; Christine A.C. Wijman; Pierre Fayad
Critical Care Medicine | 1999
Daniel F. Hanley; Panayiotis N. Varelas
Archive | 2009
Marek A. Mirski; Panayiotis N. Varelas
/data/revues/07490704/v24i1/S0749070407000954/ | 2011
Marek A. Mirski; Panayiotis N. Varelas