İbrahim Özkan Akıncı

Comparison of 3% Hypertonic Saline and 20% Mannitol for Reducing Intracranial Pressure in Patients Undergoing Supratentorial Brain Tumor Surgery: A Randomized, Double-blind Clinical Trial

Background: In the present study, we hypothesized that 3% hypertonic saline (HS) is more effective than 20% mannitol to reduce intracranial pressure (ICP) and to modify brain bulk in patients undergoing an elective supratentorial craniotomy. Materials and Methods: After institutional review board approval, patients scheduled to undergo supratentorial craniotomy were enrolled into this prospective, randomized, double-blind study. The patients were monitored for routine hemodynamic parameters, depth of anesthesia, and ICP. They received 5 mL/kg 20% mannitol (n=20) or 3% HS (n=19) as infusion for 15 minutes. The patients’ ICP values were monitored during hypertonic fluid infusion and throughout 30 minutes after infusion as a primary outcome. Secondary outcomes were hemodynamic variables, serum sodium value, blood gases, and surgeon brain relaxation assessment score (1=relaxed, 2=satisfactory, 3=firm, 4=bulging). In addition, the length of intensive care unit and hospital stay were recorded. Results: Demographic and tumor characteristics were similar between groups. The basal (before hypertonic infusion, ICPT0) and last (30 min after hypertonic infusion finished, ICPT45) ICP values were 13.7±3.0 and 9.5±1.9 mm Hg, respectively, for the M group, which were comparable with the corresponding levels of 14.2±2.8 and 8.7±1.1 mm Hg in the HS group (P>0.05). The median amount of ICP reduction between T0 and T45 timepoints were 4 (1 to 7) and 5 (1 to 9) mm Hg for group M and group HS, respectively (P=0.035). Baseline central venous pressure, pulse pressure variation, and serum sodium and lactate values were similar between groups, but the last measured pulse pressure variation and lactate value were lower, and sodium value was higher in group HS than in group M (P<0.05). Duration of hospital and intensive care unit stay were similar between groups. Conclusions: Our results suggest that 3% HS provided more effective ICP reduction than 20% mannitol during supratentorial brain tumor surgery.

Effects of prone and jackknife positioning on lumbar disc herniation surgery.

Background: Intra-abdominal hypertension due to surgical position increases bleeding at the surgical site. In this study, we evaluated the impact of prone and jackknife position on intra-abdominal pressure (IAP), lung mechanics, blood loss at the surgical site, and duration of the surgical procedure on lumbar disc operations. Methods: Forty patients operated for single-space lumber disc herniation were included in our study. All patients were ASA I-II and 18 to 70 years old. Patients who had undergone previous spinal surgery, were on anticoagulant or anti-aggregant therapy, had hypertension, cardiac, respiratory, liver, or renal disorders, and were obese (Body Mass Index >35 kg/m2) were excluded. Patients were randomly assigned to either the prone or the jackknife position for surgery. Differences in lung mechanics, IAP, and surgical-site blood loss were calculated in both patient groups. Changes in pulmonary and abdominal pressure levels were measured both in face-up and down positions. Results: Bleeding at the surgical site (prone: 180.0±100.0 mL, jackknife: 100.0±63.6 mL, P=0.018) and IAP (prone: 11.0±3.0 mm Hg, jackknife: 8.0±2.0 mm Hg, P=0.006) were significantly reduced when patients were in the jackknife position. Operating time was approximately 40 minutes shorter in the jackknife position group, although this difference was not significant. Conclusions: The jackknife position causes less IAP elevation and less surgical site bleeding compared with the prone position. The jackknife position is the preferred choice for single-level lumbar disc surgery in healthy, nonobese patients.

Early postoperative recovery after intracranial surgical procedures. Comparison of the effects of sevoflurane and desflurane

PURPOSE: To compared the effects of sevoflurane and desflurane on early anesthesia recovery in patients undergoing to craniotomy for intracranial lesions. METHODS: After IRB approval, the study included 50 patients aged 18-70 years who had ASA physical statuses of I-II and were scheduled for intracranial surgery. Patients were randomly divided into two groups: sevoflurane and desflurane. Anaesthesia was routinely induced in all patients followed by desflurane 5%-6% or sevoflurane 1%-2%. Moreover remifentanil infusion (0.05-0.2 mcg/kg/min) was adjusted to maintain mean arterial pressure (MAP) within 20% baseline and heart rate <90 bpm. Postoperatively, patients were evaluated over time for responses to painful stimulus, eye opening, hand squeezing, extubation, orientation and time required to achieve a Modified Aldrete Score of 9-10. Parametric and non-parametric data were assessed using Students t- and Mann-Whitney U tests, respectively. A p<0.05 was taken as statistically significant. RESULTS: The times to responses to painful stimuli (7.7±2.7 vs. 4.8±1.7 min.; p<0.001), emergence (9.5±2.81 vs. 6.3±2.2 min.; p<0.001), hand-squeezing (12.1±2.9 vs. 8.2±2.3 min.; p<0.001), extubation (10.1±2.87 vs. 7.1±1.6 min.; p<0.001), orientation (15.3±3.2 vs. 10.3±2.7 min.; p<0.001) and Aldrete score of 9-10 (23.3±6.1 vs. 15.8±3.8 min.; p<0.001) were significantly lower with desflurane-based anaesthesia vs. sevoflurane-based anaesthesia. CONCLUSION: Desflurane yields early recovery functions and facilitates early postoperative neurologic examinations of intracranial surgery patients.

The Comparison of Automatic Tube Compensation (ATC) and T-piece During Weaning

OBJECTIVE Automatic Tube Compensation (ATC) is a newly developed mechanical ventilatory support method. The aim of this study was to compare the ATC and the T-piece as a weaning method. METHODS Patients who were treated in ICU with mechanical ventilation for longer than 24 hours were included in this prospective clinical study. Fifty patients were divided into two groups for weaning, ATC or T-piece group. Patients tolerating 30 minutes spontaneous breathing trial underwent immediate extubation. The following parameters were recorded just before the spontaneous breathing trial and every 5 minutes during the 30 minute period; PEEP, Pplt, Pmean, FiO2, heart rate, systolic blood pressure, diastolic blood pressure, respiratory rate, SaO2, ETCO2. The primary outcome of the study was successful extubation defined as the ability to maintain spontaneous breathing for 48 hours after extubation. RESULTS The mean duration of weaning were 4.96 days and 7.42 days in the ATC and T-piece groups, respectively (p value 0.022). There were no significant differences between the groups with respect to the hemodynamic parameters, mechanical ventilation and gas exchange parameters. CONCLUSION In terms of success for weaning, there was no superiority between the ATC and the T-Piece methods for spontaneous breathing and it was concluded that each of the methods can be used for weaning. The ATC group were compared in terms of successful weaning period but have shown no significant periods of time were found to be lower.

A Comparison of the Effects of 20% Mannitol and 3% NaCl on Coagulation Parameters In Vitro using ROTEM: A Prospective Randomized Crossover Study

OBJECTIVE The aim of the present study is to compare the effect of 20% mannitol and 3% NaCl on blood coagulation in vitro using rotational thromboelastometry (ROTEM). METHODS Twenty-millilitre blood samples were obtained from 15 volunteers. In each group, 2 mL blood samples were collected into both polypropylene tubes and EDTA tubes for ROTEM and hemogram analysis. After sampling, blood samples were diluted with test solutions. Group C (control): Only blood, Group M (mannitol): 7% vol 20% mannitol concentration in the blood, Group hypertonic saline (HS): 7% vol 3% hypertonic saline (NaCl) in the blood, Group M/H (mannitol and hydroxyethyl starch solutions [HES]): 6% vol 20% mannitol concentration and 8% vol HES in the blood and Group HS/H (hypertonic saline and HES): 6% vol 3% hypertonic saline concentration and 8% vol HES in the blood. The following thromboelastometric parameters were measured automatically: clotting time (CT) and clot formation time (CFT) with intrinsic activation by tissue factor (InTEM), CT, CFT and maximum clot firmness (MCF) with extrinsic activation by tissue factor (ExTEM) and MCF with FibTEM. RESULTS The ExTEM CT value was found to be significantly longer in the M/H group than in the controls. The ExTEM CFT median and percentile values were: group C: 85 s (70-95 s), group M: 115 s (94-128 s), group HS: 102 s (84-114 s), group M/H: 128 s (110-144 s) and group HS/H: 118 s (107-132 s). In all the groups, FibTEM MCF values were significantly lower than the control and also there was a significant difference between groups M and HS according to FibTEM MCF values. CONCLUSION Whole-blood coagulation disorder induced by these solutions is mainly dependent on fibrinogen and fibrin interaction. However, 3% HS has much less negative effect on coagulation.

Pulse Pressure Variation and Weight-Loss Percentage Predict Hypotension After Anesthesia Induction in Neurosurgery Patients: A Prospective, Observational, Blinded Study.

Background: Hypotension after anesthesia induction is a common problem and is partly related to patient volume status. The present study aimed to investigate the correlation between blood pressure change and pulse pressure variation (PPV), and percentage of weight loss while determining threshold for hypotension by receiver operating characteristic analysis. Methods: We analyzed 231 neurosurgery patients. In all patients, propofol was used for standard anesthesia induction. Patient demographics, medical histories, fasting duration, percentage weight loss, baseline blood pressure, and PPV during normal tidal volume breathing and that during forced inspiratory breathing (PPVfi) were recorded. Hemodynamic changes within 10 minutes of intubation were observed. Patients developing hypotension and severe hypotension were determined; lowest mean arterial pressure (MAP) and systolic arterial pressure (SAP) values were recorded, and their differences relative to baseline values were calculated. Results: The incidence of hypotension was 18.6%. Both percentage weight loss and PPVfi were correlated with the changes in MAP and SAP. A PPVfi>14 identified all observed hypotensive episodes with 86% sensitivity and 86.2% specificity, whereas percentage weight loss >1.75% identified all observed hypotensive episodes with 81.4% sensitivity and 70.7% specificity. Furthermore, PPVfi>16.5 identified severe hypotension with 85% sensitivity and 90.5% specificity, whereas percentage weight loss >1.95% identified severe hypotension with 85% sensitivity and 73% specificity. Conclusions: Percentage weight loss and PPVfi are good predictors of hypotension after anesthesia induction and, thus, may allow anesthesiologists to adopt preventative measures and ensure safer anesthesia induction.

Evaluation of risk factors and development of acute kidney injury in aneurysmal subarachnoid hemorrhage, head injury, and severe sepsis/septic shock patients during ICU treatment

BACKGROUND There are few studies examining development of acute kidney injury (AKI) in the various types of patients in intensive care units (ICUs). Presently described is evaluation of risk factors and development of AKI in different groups of ICU patients. METHODS Present study was performed in 3 different ICUs. Development of AKI was measured using Acute Kidney Injury Network (AKIN) classification system. Total of 300 patients who were treated in trauma, neurosurgery, or general ICU departments (due to head injury, aneurysmal subarachnoid hemorrhage [aSAH], or severe sepsis/septic shock, respectively) were assessed for incidence, risk factors, and development of AKI. RESULTS AKI did not develop in aSAH patients when evaluated based on serum creatinine level; however, it was observed in 5% of aSAH patients according to volume adjusted creatinine (VACr) level. AKI developed in 76% of sepsis group, and in 20% of head injury group, based on AKIN classification, according to both serum and VACr levels. Incidence of AKI was significantly higher in sepsis group (p<0.001). Only use of vasopressor was significantly related to AKI development in sepsis and head injury groups. Mortality rate was 8%, 22%, and 42% in aSAH, head injury, and sepsis groups, respectively. AKI development and vasopressor use were significantly related to mortality in sepsis group. CONCLUSION Despite similar characteristics and risk factors, there were fewer instances of AKI in aSAH group. Hypertension or hydration therapy used to treat vasospasm and polyuria due to cerebral salt-wasting syndrome may prevent aSAH patients from developing AKI.

Recruitment Maneuver Does not Increase the Risk of Ventilator Induced Lung Injury

BACKGROUND Mechanical ventilation (MV) may induce lung injury. AIMS To assess and evaluate the role of different mechanical ventilation strategies on ventilator-induced lung injury (VILI) in comparison to a strategy which includes recruitment manoeuvre (RM). STUDY DESIGN Randomized animal experiment. METHODS Thirty male Sprague-Dawley rats were anaesthetised, tracheostomised and divided into 5 groups randomly according to driving pressures; these were mechanically ventilated with following peak alveolar opening (Pao) and positive end-expiratory pressures (PEEP) for 1 hour: Group 15-0: 15 cmH2O Pao and 0 cmH2O PEEP; Group 30-10: 30 cmH2O Pao and 10 cmH2O PEEP; Group 30-5: 30 cmH2O Pao and 5 cmH2O PEEP; Group 30-5&RM: 30 cmH2O Pao and 5 cmH2O PEEP with additional 45 cmH2O CPAP for 30 seconds in every 15 minutes; Group 45-0: 45 cmH2O Pao and 0 cmH2O PEEP Before rats were sacrificed, blood samples were obtained for the evaluation of cytokine and chemokine levels; then, the lungs were subsequently processed for morphologic evaluation. RESULTS Oxygenation results were similar in all groups; however, the groups were lined as follows according to the increasing severity of morphometric evaluation parameters: Group 15-0: (0±0.009) < Group 30-10: (0±0.14) < Group 30-5&RM: (1±0.12) < Group 30-5: (1±0.16) < Group 45-0: (2±0.16). Besides, inflammatory responses were the lowest in 30-5&RM group compared to all other groups. TNF-α, IL-1β, IL-6, MCP-1 levels were significantly different between group 30-5&RM and group 15-0 vs. group 45-0 in each group. CONCLUSION RM with low PEEP reduces the risk of ventilator-induced lung injury with a lower release of systemic inflammatory mediators in response to mechanical ventilation.

Effect of Lumbar Puncture in Patients with Aneurysmal Subarachnoid Hemorrhage Treated Microsurgically or Endovascularly

OBJECTIVE The aim of this study was to evaluate the effect of treatment modality (surgical clipping vs. endovascular coiling) and lumbar puncture (LP) in patients with aneurysmal subarachnoid hemorrhage (SAH) based on neurologic status on admission and clinical outcome. PATIENTS AND METHODS One hundred forty-eight consecutive patients with ruptured intracranial aneurysms treated via endovascular or surgical methods were included in our study. Patients who refused further therapy or received only supportive therapy because of bad neurologic status were excluded. Severity of SAH was evaluated using the Fisher score. World Federation of Neurosurgical Societies (WFNS) and Hunt and Hess (H&H) scores were used for evaluation of neurologic status. Glasgow Outcome Scale scores and modified Rankin scores were used for outcome evaluation. RESULTS We found that modified Rankin scores were significantly lower in the surgical clipping group (1.1 ± 1.4) than in the endovascular coiling group (1.7 ± 1.8) (p: 0.04). The positive lumbar puncture [LP(+)] group had similar outcome scores as the negative lumbar puncture [LP(-)] group, although the LP(+) group had worse initial SAH evaluation scores (WFNS 1.64 ± 0.95-1.23 ± 0.61, p: 0.0004 and H&H 2.18 ± 1.07-1.65 ± 0.88, p: 0.001). CONCLUSION Surgical clipping might improve clinical outcome better than endovascular coiling, although a more confident conclusion requires absolute randomization of patients for both treatments. LP could also improve clinical outcome in patients with high initial SAH evaluation scores.