Browsing by Author "Gupta, Dhanesh K"

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    Adenosine-induced flow arrest to facilitate intracranial aneurysm clip ligation: dose-response data and safety profile.
    (Anesth Analg, 2010-05-01) Bebawy, John F; Gupta, Dhanesh K; Bendok, Bernard R; Hemmer, Laura B; Zeeni, Carine; Avram, Michael J; Batjer, H Hunt; Koht, Antoun
    BACKGROUND: Adenosine-induced transient flow arrest has been used to facilitate clip ligation of intracranial aneurysms. However, the starting dose that is most likely to produce an adequate duration of profound hypotension remains unclear. We reviewed our experience to determine the dose-response relationship and apparent perioperative safety profile of adenosine in intracranial aneurysm patients. METHODS: This case series describes 24 aneurysm clip ligation procedures performed under an anesthetic consisting of remifentanil, low-dose volatile anesthetic, and propofol in which adenosine was used. The report focuses on the doses administered; duration of systolic blood pressure <60 mm Hg (SBP(<60 mm Hg)); and any cardiovascular, neurologic, or pulmonary complications observed in the perioperative period. RESULTS: A median dose of 0.34 mg/kg ideal body weight (range: 0.29-0.44 mg/kg) resulted in a SBP(<60 mm Hg) for a median of 57 seconds (range: 26-105 seconds). There was a linear relationship between the log-transformed dose of adenosine and the duration of a SBP(<60 mm Hg) (R(2) = 0.38). Two patients developed transient, hemodynamically stable atrial fibrillation, 2 had postoperative troponin levels >0.03 ng/mL without any evidence of cardiac dysfunction, and 3 had postoperative neurologic changes. CONCLUSIONS: For intracranial aneurysms in which temporary occlusion is impractical or difficult, adenosine is capable of providing brief periods of profound systemic hypotension with low perioperative morbidity. On the basis of these data, a dose of 0.3 to 0.4 mg/kg ideal body weight may be the recommended starting dose to achieve approximately 45 seconds of profound systemic hypotension during a remifentanil/low-dose volatile anesthetic with propofol induced burst suppression.
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    An evaluation of remifentanil-sevoflurane response surface models in patients emerging from anesthesia: model improvement using effect-site sevoflurane concentrations.
    (Anesth Analg, 2010-08) Johnson, Ken B; Syroid, Noah D; Gupta, Dhanesh K; Manyam, Sandeep C; Pace, Nathan L; LaPierre, Cris D; Egan, Talmage D; White, Julia L; Tyler, Diane; Westenskow, Dwayne R
    INTRODUCTION: We previously reported models that characterized the synergistic interaction between remifentanil and sevoflurane in blunting responses to verbal and painful stimuli. This preliminary study evaluated the ability of these models to predict a return of responsiveness during emergence from anesthesia and a response to tibial pressure when patients required analgesics in the recovery room. We hypothesized that model predictions would be consistent with observed responses. We also hypothesized that under non-steady-state conditions, accounting for the lag time between sevoflurane effect-site concentration (Ce) and end-tidal (ET) concentration would improve predictions. METHODS: Twenty patients received a sevoflurane, remifentanil, and fentanyl anesthetic. Two model predictions of responsiveness were recorded at emergence: an ET-based and a Ce-based prediction. Similarly, 2 predictions of a response to noxious stimuli were recorded when patients first required analgesics in the recovery room. Model predictions were compared with observations with graphical and temporal analyses. RESULTS: While patients were anesthetized, model predictions indicated a high likelihood that patients would be unresponsive (> or = 99%). However, after termination of the anesthetic, models exhibited a wide range of predictions at emergence (1%-97%). Although wide, the Ce-based predictions of responsiveness were better distributed over a percentage ranking of observations than the ET-based predictions. For the ET-based model, 45% of the patients awoke within 2 min of the 50% model predicted probability of unresponsiveness and 65% awoke within 4 min. For the Ce-based model, 45% of the patients awoke within 1 min of the 50% model predicted probability of unresponsiveness and 85% awoke within 3.2 min. Predictions of a response to a painful stimulus in the recovery room were similar for the Ce- and ET-based models. DISCUSSION: Results confirmed, in part, our study hypothesis; accounting for the lag time between Ce and ET sevoflurane concentrations improved model predictions of responsiveness but had no effect on predicting a response to a noxious stimulus in the recovery room. These models may be useful in predicting events of clinical interest but large-scale evaluations with numerous patients are needed to better characterize model performance.
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    Hematocrit as a predictor of preoperative transfusion-associated complications in spine surgery: A NSQIP study.
    (Clinical neurology and neurosurgery, 2021-01) Mehta, Vikram A; Van Belleghem, Florence; Price, Meghan; Jaykel, Matthew; Ramirez, Luis; Goodwin, Jessica; Wang, Timothy Y; Erickson, Melissa M; Than, Khoi D; Gupta, Dhanesh K; Abd-El-Barr, Muhammad M; Karikari, Isaac O; Shaffrey, Christopher I; Rory Goodwin, C

    Background context

    Preoperative optimization of medical comorbidities prior to spinal surgery is becoming an increasingly important intervention in decreasing postoperative complications and ensuring a satisfactory postoperative course. The treatment of preoperative anemia is based on guidelines made by the American College of Cardiology (ACC), which recommends packed red blood cell transfusion when hematocrit is less than 21% in patients without cardiovascular disease and 24% in patients with cardiovascular disease. The literature has yet to quantify the risk profile associated with preoperative pRBC transfusion.

    Purpose

    To determine the incidence of complications following preoperative pRBC transfusion in a cohort of patients undergoing spine surgery.

    Study design

    Retrospective review of a national surgical database.

    Patient sample

    The national surgical quality improvement program database OUTCOME NEASURES: Postoperative physiologic complications after a preoperative transfusion. Complications were defined as the occurrence of any DVT, PE, stroke, cardiac arrest, myocardial infarction, longer length of stay, need for mechanical ventilation greater than 48 h, surgical site infections, sepsis, urinary tract infections, pneumonia, or higher 30-day mortality.

    Methods

    The national surgical quality improvement program database was queried, and patients were included if they had any type of spine surgery and had a preoperative transfusion.

    Results

    Preoperative pRBC transfusion was found to be protective against complications when the hematocrit was less than 20% and associated with more complications when the hematocrit was higher than 20%. In patients with a hematocrit higher than 20%, pRBC transfusion was associated with longer lengths of stay, and higher rates of ventilator dependency greater than 48 h, pneumonia, and 30-day mortality.

    Conclusion

    This is the first study to identify an inflection point in determining when a preoperative pRBC transfusion may be protective or may contribute to complications. Further studies are needed to be conducted to stratify by the prevalence of cardiovascular disease.
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    Preoperative optimization for patients undergoing elective spine surgery.
    (Clinical neurology and neurosurgery, 2021-01-14) Wang, Timothy Y; Price, Meghan; Mehta, Vikram A; Bergin, Stephen M; Sankey, Eric W; Foster, Norah; Erickson, Melissa; Gupta, Dhanesh K; Gottfried, Oren N; Karikari, Isaac O; Than, Khoi D; Goodwin, C Rory; Shaffrey, Christopher I; Abd-El-Barr, Muhammad M
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    Preprocedural Checklist for Magnetic Resonance Imaging Patients Undergoing General Anesthesia: A Process Improvement Plan to Enhance Reimbursement.
    (The health care manager, 2018-06-22) Hartl, Susan; Rice, Andi N; Gupta, Dhanesh K; Goode, Victoria
    Thorough documentation is essential for hospital reimbursement from payors such as the Centers for Medicare & Medicaid Services. Inconsistencies and incomplete documentation can occur if workflow is not standardized especially in cases with interdisciplinary involvement. Documentation for patients undergoing magnetic resonance imaging (MRI) with anesthesia services was examined and revealed an opportunity for improvement to avoid financial losses. A preprocedure checklist to improve documentation and standardize workflow was implemented. We compared documentation from preintervention MRI to postintervention MRI with anesthesia services. Documentation that met the reimbursement requirements increased from 5% in the preintervention group to 90% in the postintervention group after the preprocedural checklist implementation. A cost estimate showed a reduction in potential revenue loss from preimplementation to postimplementation groups. The standardization of workflow with the aid of checklists helped meet the documentation requirements for adequate reimbursements and reduced the risk of potential reimbursement losses from payors.
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    The incidence of unacceptable movement with motor evoked potentials during craniotomy for aneurysm clipping.
    (World Neurosurg, 2014-01) Hemmer, Laura B; Zeeni, Carine; Bebawy, John F; Bendok, Bernard R; Cotton, Mathew A; Shah, Neil B; Gupta, Dhanesh K; Koht, Antoun
    OBJECTIVE: To review the experience at a single institution with motor evoked potential (MEP) monitoring during intracranial aneurysm surgery to determine the incidence of unacceptable movement. METHODS: Neurophysiology event logs and anesthetic records from 220 craniotomies for aneurysm clipping were reviewed for unacceptable patient movement or reason for cessation of MEPs. Muscle relaxants were not given after intubation. Transcranial MEPs were recorded from bilateral abductor hallucis and abductor pollicis muscles. MEP stimulus intensity was increased up to 500 V until evoked potential responses were detectable. RESULTS: Out of 220 patients, 7 (3.2%) exhibited unacceptable movement with MEP stimulation-2 had nociception-induced movement and 5 had excessive field movement. In all but one case, MEP monitoring could be resumed, yielding a 99.5% monitoring rate. CONCLUSIONS: With the anesthetic and monitoring regimen, the authors were able to record MEPs of the upper and lower extremities in all patients and found only 3.2% demonstrated unacceptable movement. With a suitable anesthetic technique, MEP monitoring in the upper and lower extremities appears to be feasible in most patients and should not be withheld because of concern for movement during neurovascular surgery.