Browsing by Author "Chatterjee, Nilay"

Now showing 1 - 3 of 3
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    Changes in Left Ventricular Preload, Afterload, and Cardiac Output in Response to a Single Dose of Mannitol in Neurosurgical Patients Undergoing Craniotomy: A Transesophageal Echocardiographic Study
    (JOURNAL OF NEUROSURGICAL ANESTHESIOLOGY, 2012)
    Background: Mannitol increases intravascular volume by withdrawing water from the brain and causes significant changes in stroke volume, cardiac output (CO), systemic vascular resistance, central venous pressure (CVP), and blood pressure. No previous studies have demonstrated changes in left ventricular (LV) preload, afterload, and CO using transesophageal echocardiography (TEE).Methods: Fifteen adult patients undergoing elective supratentorial craniotomy received 20% mannitol 1.0 gm/kg over 15 minutes before dural opening. The following hemodynamic and TEE-derived parameters were recorded before and after the administration of mannitol: heart rate (HR), mean arterial pressure (MAP), CVP, LV end diastolic area (EDA), end systolic area, fractional area change, stroke volume, and CO.Results: EDA and CVP significantly increased at 5 minutes (P=0.002 and < 0.001) after mannitol infusion and remained insignificantly elevated till 15 minutes, thereafter returning to baseline values. CO also increased significantly at 5 and 15 minutes (P=0.001 and 0.013) and remained insignificantly elevated till 25 minutes, and thereafter returned to baseline values. A concomitant significant decline in systemic vascular resistance was observed at 5 and 15 minutes (P=0.002 and 0.008 at 5 and 15 min, respectively). Although EDA increased significantly at 5 minutes, there were no appreciable changes in MAP and HR throughout the study period.Conclusions: In conclusion, in patients undergoing craniotomy, TEE demonstrated that a single bolus dose of 20% mannitol (1.0 gm/kg) caused significant but short-duration alterations in LV preload, afterload, and CO without concomitant changes in hemodynamic variables (MAP/HR).
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    Gabapentin Premedication Decreases the Hemodynamic Response to Skull Pin Insertion in Patients Undergoing Craniotomy
    (JOURNAL OF NEUROSURGICAL ANESTHESIOLOGY, 2011)
    Background: In patients undergoing craniotomy, skull pin insertion produces significant increases in heart rate (HR) and blood pressure. We investigated whether premedication with gabapentin would prevent or attenuate this increase.Methods: Forty-seven ASA I and II patients, 18 to 60 years, undergoing elective craniotomy for intracranial tumor surgery were recruited prospectively and randomly divided into 3 groups; L (oral placebo plus 2% lidocaine infiltration at pin sites; n = 12), G (oral gabapentin 900 mg plus normal saline infiltration; n = 21) and GL (oral gabapentin 900mg plus 2% lidocaine infiltration; n = 14). The oral medications were administered 2 hours before induction of anesthesia. Measurements were made at preinduction baseline, before skull pin insertion and at every 1 minute from pin insertion till end of 10 minutes.Results: Forty-three patients completed the study (L, n = 11; G, n = 20; GL, n = 12). Premedication with gabapentin significantly attenuated the rise in systolic (SBP) and mean arterial pressure (MAP) after pin insertion when compared with placebo (for SBP, P < 0.001 at 1 and 2 min and < 0.05 at 3 to 5 min between L and G; P < 0.001 at 1 to 4 min and < 0.05 at 5 min between L and GL; for MAP, P < 0.05 at 1 min, < 0.001 at 2 min and < 0.05 at 3 to 4 min between L and G; P < 0.001 at 1 to 2 min and < 0.05 at 3 to 5 min between L and GL). HR responses were also attenuated in patients premedicated with gabapentin; however, the responses were more variable in group G (P = 0.03 between L and G at 4 min after pin insertion) as compared with group GL (P < 0.05 at 1 min, < 0.001 at 2 min and < 0.05 at 3 to 10 min between L and GL).Conclusion: In conclusion, 900mg of gabapentin, administered orally 2 hours before induction of anesthesia along with lidocaine scalp infiltration abolished the hemodynamic response after skull pin insertion. Premedication with gabapentin alone significantly attenuated the SBP and MAP; however, HR responses were more variable. A larger trial is required to corroborate the findings of the study before clinical recommendations would be warranted.
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    Postoperative sialadenitis following retromastoid suboccipital craniectomy for posterior fossa tumor
    (JOURNAL OF ANESTHESIA, 2009)
    During retromastoid and far-lateral posterior fossa surgical approaches the head may be positioned at the extreme limits of rotation and extension. In rare instances, patients may develop acute sialadenitis after surgery as a consequence of such positioning. In those patients, the neck/facial swelling is contralateral to the craniectomy site. The mechanism implicated in acute sialadenitis in the patient described in this report was because of obstruction to the salivary duct due to surgical positioning. The course of this complication is typically benign if it is identified early in the postoperative period.