Effect of different positive end expiratory pressure levels on optic nerve sheath diameter in patients with or without midline shift who are undergoing supratentorial craniotomy.

PURPOSE: In general, high levels of PEEP application is avoided in patients undergoing craniotomy to prevent a rise in ICP. But that approach would increase the risk of secondary brain injury especially in hypoxemic patients. Because the optic nerve sheath is distensible, a rise in ICP is associated with an increase in the optic nerve sheath diameter (ONSD). The cutoff value for elevated ICP assessed by ONSD is between 5.6 and 6.3 mm. We aimed to evaluate the effect of different PEEP levels on ONSD and compare the effect of different PEEP levels in patients with and without intracranial midline shift. METHODS: This prospective observational study was performed in aged 18-70 years, ASA I-III, 80 patients who were undergoing supratentorial craniotomy. After the induction of general anesthesia, the ONSD's were measured by the linear transducer from 3 mm below the globe at PEEP values of 0-5-10 cmH2O. The ONSD were compered between patients with (n = 7) and without midline shift (n = 73) at different PEEP values. RESULTS: The increases in ONSD due to increase in PEEP level were determined (p < 0.001). No difference was found in the comparison of ONSD between patients with and without midline shift in different PEEP values (p = 0.329, 0.535, 0.410 respectively). But application of 10 cmH2O PEEP in patients with a midline shift increased the mean ONSD value to 5.73 mm. This value is roughly 0.1 mm higher than the lower limit of the ONSD cutoff value. CONCLUSIONS: The ONSD in adults undergoing supratentorial tumor craniotomy, PEEP values up to 5 cmH2O, appears not to be associated with an ICP increase; however, the ONSD exceeded the cutoff for increased ICP when a PEEP of 10 cmH2O was applied in patients with midline shift.

Postoperative neurocognitive disorders: A clinical guide.

For years, postoperative cognitive outcomes have steadily garnered attention, and in the past decade, they have remained at the forefront. This prominence is primarily due to empirical research emphasizing their potential to compromise patient autonomy, reduce quality of life, and extend hospital stays, and increase morbidity and mortality rates, especially impacting elderly patients. The underlying pathophysiological process might be attributed to surgical and anaesthesiological-induced stress, leading to subsequent neuroinflammation, neurotoxicity, burst suppression and the development of hypercoagulopathy. The beneficial impact of multi-faceted strategies designed to mitigate the surgical and perioperative stress response has been suggested. While certain potential risk factors are difficult to modify (e.g., invasiveness of surgery), others - including a more personalized depth of anaesthesia (EEG-guided), suitable analgesia, and haemodynamic stability - fall under the purview of anaesthesiologists. The ESAIC Safe Brain Initiative research group recommends implementing a bundle of non-invasive preventive measures as a standard for achieving more patient-centred care. Implementing multi-faceted preoperative, intraoperative, and postoperative preventive initiatives has demonstrated the potential to decrease the incidence and duration of postoperative delirium. This further validates the importance of a holistic, team-based approach in enhancing patients' clinical and functional outcomes. This review aims to present evidence-based recommendations for preventing, diagnosing, and treating postoperative neurocognitive disorders with the Safe Brain Initiative approach.

Cerebral oxygenation assessed by near-infrared spectroscopy in the sitting and prone positions during posterior fossa surgery: a prospective, randomized clinical study.

OBJECTIVES: Sitting position (SP) or prone position (PP) are used for posterior fossa surgery. The SP induced reduction in cerebral blood flow and cerebral oxygen saturation (rSO2) has been shown in shoulder surgeries, but there is not enough data in intracranial tumor surgery. Studies showed that PP is safe in terms of cerebral oxygen saturation in patients undergoing spinal surgery. Our hypothesis is that the SP may improve cerebral oxygenation in the patients with intracranial pathologies due to reduction in intracranial pressure. Therefore, we compared the effects of the SP and PP on rSO2 in patients undergoing posterior fossa tumor surgery. METHODS: Data were collected patients undergoing posterior fossa surgery, 20 patients in SP compared to 21 patients in PP. The rSO2 was assessed using INVOS monitor. Heart rate (HR), mean arterial pressure (MAP), EtCO2, BIS, and bilateral rSO2 were recorded preoperatively, and at 5, 8, and 11.ßminutes after the intubation and every 3.ßminutes after patient positioning until the initial surgical incision. RESULTS: Cerebral oxygenation slowly reduced in both the sitting and prone position patients following the positioning (p.ß<.ß0.002), without any difference between the groups. The HR and MAP were lower in the sitting SP after positioning compared to the PP. CONCLUSION: Neurosurgery in the SP and PP is associated with slight reduction in cerebral oxygenation. We speculate that if we rise the lower limit of MAP, we might have showed the beneficial effect of the SP on rSO2.

Cerebral oxygenation assessed by near-infrared spectroscopy in the sitting and prone positions during posterior fossa surgery: a prospective, randomized clinical study

Abstract Objectives: Sitting position (SP) or prone position (PP) are used for posterior fossa surgery. The SP induced reduction in cerebral blood flow and cerebral oxygen saturation (rSO2) has been shown in shoulder surgeries, but there is not enough data in intracranial tumor surgery. Studies showed that PP is safe in terms of cerebral oxygen saturation in patients undergoing spinal surgery. Our hypothesis is that the SP may improve cerebral oxygenation in the patients with intracranial pathologies due to reduction in intracranial pressure. Therefore, we compared the effects of the SP and PP on rSO2 in patients undergoing posterior fossa tumor surgery. Methods: Data were collected patients undergoing posterior fossa surgery, 20 patients in SP compared to 21 patients in PP. The rSO2 was assessed using INVOS monitor. Heart rate (HR), mean arterial pressure (MAP), EtCO2, BIS, and bilateral rSO2 were recorded preoperatively, and at 5, 8, and 11 minutes after the intubation and every 3 minutes after patient positioning until the initial surgical incision. Results: Cerebral oxygenation slowly reduced in both the sitting and prone position patients following the positioning (p < 0.002), without any difference between the groups. The HR and MAP were lower in the sitting SP after positioning compared to the PP. Conclusion: Neurosurgery in the SP and PP is associated with slight reduction in cerebral oxygenation. We speculate that if we rise the lower limit of MAP, we might have showed the beneficial effect of the SP on rSO2.

Effects of propofol, desflurane, and sevoflurane on respiratory functions following endoscopic endonasal transsphenoidal pituitary surgery: a prospective randomized study.

BACKGROUND: General anesthesia with intravenous or inhalation anesthetics reduces respiratory functions. We investigated the effects of propofol, desflurane, and sevoflurane on postoperative respiratory function tests. METHODS: This single-center randomized controlled study was performed in a university hospital from October 2015 to February 2017. Ninety patients scheduled for endoscopic endonasal transsphenoidal pituitary surgery were randomly categorized into either of these three groups: propofol (n = 30, the Group TIVA), desflurane (n = 30, the Group D) or sevoflurane (n = 30, the Group S). We analyzed the patients before, after, and 24 h following surgery, to identify the following parameters: forced expiratory volume in 1 second (FEV1) %, forced vital capacity (FVC) %, FEV1/FVC, and arterial blood gases (ABG). Furthermore, we also recorded the intraoperative dynamic lung compliance and airway resistance values. RESULTS: We did not find any significant differences in FEV1 values (primary outcome) among the groups (P = 0.336). There was a remarkable reduction in the FEV1 and FVC values in all groups postoperatively relative to the baseline (P < 0.001). The FVC, FEV1/FVC, ABG analysis, compliance, and airway resistance were similar among the groups. Intraoperative dynamic compliance values were lower at the 1st and 2nd hours than those immediately after intubation (P < 0.001). CONCLUSIONS: We demonstrated that propofol, desflurane, and sevoflurane reduced FEV1 and FVC values postoperatively, without any significant differences among the drugs.

The Effects of Locally Administered Morphine Over the Dura on Postoperative Morphine Consumption and Pain After Lumbar Disc Surgery: A Prospective, Randomised, Double-Blind and Placebo-Controlled Study.

OBJECTIVE: Effective pain management by avoiding side effects in the perioperative period is essential for patient outcome. Lumbar disc surgery is associated with moderate to severe postoperative pain, and opioids are widely used. The primary aim of the present study was to compare the effects of 1 mg and 2 mg morphine-impregnated absorbable cellulose haemostat material placed over the dura on morphine consumption, and the secondary aims were to compare pain scores and opioid-related side effects during postoperative 24 h. METHODS: The study included 44 patients (American Society of Anesthesiologists I and II). After the discectomy procedure and before the closure, in Group A (n=15), 1 mg morphine-impregnated absorbable cellulose haemostat material placed over the dura was used. In Group B (n=14), 2 mg morphine was used for the same technique, and in Group C (n=15) (control), normal saline was used. All patients used intravenous morphine patient-controlled analgesia pumps for 24 h following lumbar disc surgery. Morphine consumption, pain scores and opioid-related side effects were recorded at 10 min, 1, 2, 6, 12 and 24 h postoperatively. RESULTS: Morphine consumption, pain scores and opioid-related side effects were similar among the groups. CONCLUSION: Morphine-impregnated absorbable cellulose haemostat material placement over the dura after single level lumbar discectomy did not reduce postoperative morphine consumption, pain scores and incidence of opioid-related side effects.

Can Amantadine Ameliorate Neurocognitive Functions After Subarachnoid Haemorrhage? A Preliminary Study.

OBJECTIVE: Aneurysmal subarachnoid haemorrhage (SAH) may have devastating effects on patients. Motor and neurocognitive impairments may arise depending on the location and grade of the SAH. Although the effects of amantadine on neurocognitive function after traumatic brain injury have been widely studied to the best of our knowledge, their effects on recovery from SAH in humans have not been studied. The present study aimed to evaluate how amantadine influences improvement in neurocognitive function in patients with aneurysmal SAH over a period of six months. METHODS: This preliminary study included 12 patients with aneurysmal SAH who were admitted to the neurointensive care unit of Cerrahpasa Faculty of Medicine. Patients in Group A (n=5) received the standard treatment for SAH and amantadine for 30 days after admission, and those in Group C (n=7) received only the standard treatment. Neurocognitive function was evaluated using the Coma Recovery Scale-Revised and Disability Rating Scale on the first and fifth days and at the third and sixth months after admission. The primary endpoint of the present study was to compare the effects of amantadine in combination with the standard treatment to those of the standard treatment alone on the neurocognitive function of patients with SAH for over 6 months. RESULTS: Compared to the standard treatment alone, amantadine administration with the standard treatment during the early period of SAH may improve recovery. CONCLUSION: Amantadine along with the standard treatment can ameliorate neurocognitive function after SAH.

Efficacy of continuous positive airway pressure and incentive spirometry on respiratory functions during the postoperative period following supratentorial craniotomy: A prospective randomized controlled study.

STUDY OBJECTIVE: Volume controlled ventilation with low PEEP is used in neuro-anesthesia to provide constant PaCO2 levels and prevent raised intracranial pressure. Therefore, neurosurgery patients prone to atelectasis formation, however, we could not find any study that evaluates prevention of postoperative pulmonary complications in neurosurgery. DESIGN: A prospective, randomized controlled study. SETTING: Intensive care unit in a university hospital in Istanbul. PATIENTS: Seventy-nine ASAI-II patients aged between 18 and 70years scheduled for elective supratentorial craniotomy were included in the study. INTERVENTIONS: Patients randomized into 3 groups after surgery. The Group IS (n=20) was treated with incentive spirometry 5 times in 1min and 5min per hour, the Group CPAP (n=20) with continuous positive airway pressure 10 cmH2O pressure and 0.4 FiO2 via an oronasal mask 5min per hour, and the Group Control (n=20) 4L·min-1O2 via mask; all during the first 6h postoperatively. Respiratory functions tests and arterial blood gases analysis were performed before the induction of anesthesia (Baseline), 30min, 6h, 24h postoperatively. MAIN RESULTS: The IS and CPAP applications have similar effects with respect to FVC values. The postoperative 30min FEV1 values were statistically significantly reduced compared to the Baseline in all groups (p<0.0001). FEV1 values were statistically significantly increased at the postoperative 24h compared to the postoperative 30min in the Groups IS and CPAP (p<0.0001). This increase, however, was not observed in the Group Control, and the postoperative 24h FEV1 values were statistically significantly lower in the Group Control compared to the Group IS (p=0.015). CONCLUSION: Although this study is underpowered to detect differences in FEV1 values, the postoperative 24h FEV1 values were significantly higher in the IS group than the Control group and this difference was not observed between the CPAP and Control groups. It might be evaluate a favorable effect of IS in neurosurgery patients. But larger studies are needed to make a certain conclusion.

Effective and safe mannitol administration in patients undergoing supratentorial tumor surgery: A prospective, randomized and double blind study.

OBJECTIVES: Although osmotic diuresis with mannitol is commonly used to provide brain relaxation, there is no consensus regarding its optimal dose and combination with loop diuretics. The aim of the present study is to evaluate the effects of mannitol and combination of furosemide with different doses of mannitol on brain relaxation and on blood electrolytes, lactate level, urine output, fluid balance and blood osmolarity in patients undergoing supratentorial tumor surgery. PATIENTS AND METHODS: This prospective, randomized, double blind, placebo-controlled study included 51 patients (ASA I-III) scheduled for elective supratentorial craniotomy. Different doses and combinations of diuretics were administered after the bone flap removal. The Group 1 received mannitol at 0.5gkg-1 and furosemide at 0.5mgkg-1, the Group 2 received mannitol at 1gkg-1 and furosemide at 0.5mgkg-1, and the Group 3 received mannitol at 0.5gkg-1 and placebo. The primary end-point of the present study is to evaluate the effects of mannitol and combination of furosemide with different doses of mannitol on brain relaxation and the secondary end-points are to evaluate their effects on blood electrolytes, lactate level, urine output, fluid balance and blood osmolarity. RESULTS: This study shows that mannitol alone (0.5gkg-1), and the combinations of furosemide (0.5mgkg-1) with different doses of mannitol (0.5gkg-1-1gkg-1) provides adequate brain relaxation. However, administration of furosemide with low or high doses of mannitol may cause reduction in the sodium and chloride levels as well as rise in the lactate level. Moreover it may cause high urine output and negative intra-operative fluid balance. CONCLUSION: Administration of 0.5gkg-1 mannitol provides adequate brain relaxation without causing systemic side effects in patients undergoing supratentorial tumor surgery. This study is registered to clinical trials (Clinical Trials.gov identifier NCT02712476).

Which one is more effective for analgesia in infratentorial craniotomy? The scalp block or local anesthetic infiltration.

OBJECTIVES: The most painful stages of craniotomy are the placement of the pin head holder and the skin incision. The primary aim of the present study is to compare the effects of the scalp block and the local anesthetic infiltration with bupivacaine 0.5% on the hemodynamic response during the pin head holder application and the skin incision in infratentorial craniotomies. The secondary aims are the effects on pain scores and morphine consumption during the postoperative 24h. METHODS: This prospective, randomized and placebo controlled study included forty seven patients (ASA I, II and III). The scalp block was performed in the Group S, the local anesthetic infiltration was performed in the Group I and the control group (Group C) only received remifentanil as an analgesic during the intraoperative period. The hemodynamic response to the pin head holder application and the skin incision, as well as postoperative pain intensity, cumulative morphine consumption and opioid related side effects were compared. RESULTS: The scalp block reduced the hemodynamic response to the pin head holder application and the skin incision in infratentorial craniotomies. The local anesthetic infiltration reduced the hemodynamic response to the skin incision. As well as both scalp block and local anesthetic infiltration reduced the cumulative morphine consumption in postoperative 24h. Moreover, the pain intensity was lower after scalp block in the early postoperative period. CONCLUSION: The scalp block may provide better analgesia in infratentorial craniotomies than local anesthetic infiltration.

Does preoperative oral carbohydrate treatment reduce the postoperative surgical stress response in lumbar disc surgery?

OBJECTIVES: Surgical trauma produces metabolic and hormonal responses, which are characterized by insulin resistance. Due to extension of the preoperative fasting period, which increases the magnitude of postoperative insulin resistance, preoperative oral carbohydrates (POC) have been developed. PATIENTS AND METHODS: This prospective, randomized, controlled study was performed on 43 ASA I-II patients undergoing elective microsurgical lumbar discectomy. The intervention group received oral carbohydrate solution 800mL the night before and 400mL 2h prior to operation. The other group fasted for 8h prior to operation. Blood samples were obtained the day before the operation, before induction of anesthesia, after skin incision, 1h, 2h, 6h and 24h following skin incision. Blood glucose, plasma insulin, cortisol and interleukin-6 (IL-6) levels were determined. The primary endpoint was to assess the effect of POC treatment on insulin resistance and surgical stress response following lumbar disc surgery. The secondary endpoint was to assess POC's effects on postoperative nausea and vomiting. RESULTS: The serum insulin levels were higher before induction of anesthesia in the study group and returned to fasted group levels by 2h after skin incision. The plasma IL-6 levels were higher in the intervention group at 6h after the skin incision. There were no differences between the two groups with respect to blood glucose, plasma cortisol levels and the incidence of nausea and vomiting. CONCLUSION: This study suggests that use of POC treatment does not attenuate development of insulin resistance in patients undergoing lumbar disc surgery.

Comparison of Conscious Sedation and Asleep-Awake-Asleep Techniques for Awake Craniotomy.

Since awake craniotomy (AC) has become a standard of care for supratentorial tumour resection, especially in the motor and language cortex, determining the most appropriate anaesthetic protocol is very important. The aim of this retrospective study is to compare the effectiveness of conscious sedation (CS) to "awake-asleep-awake" (AAA) techniques for supratentorial tumour resection. Forty-two patients undergoing CS and 22 patients undergoing AAA were included in the study. The primary endpoint was to compare the CS and AAA techniques with respect to intraoperative pain and agitation in patients undergoing supratentorial tumour resection. The secondary endpoint was comparison of the other intraoperative complications. This study results show that the incidence of intraoperative agitation and seizure were lower in the AAA group than in the CS group. Intraoperative blood pressures were significantly higher in the CS group than in the AAA group during the pinning and incision, but the level of blood pressures did not need antihypertensive treatment. Otherwise, blood pressures were significantly higher in the AAA group than in the CS group during the neurological examination and the severity of hypertension needed statistically significant more antihypertensive treatment in the AAA group. As a result of hypertension, the amount of intraoperative bleeding was higher in the AAA group than in the CS group. In conclusion, the AAA technique may provide better results with respect to agitation and seizure, but intraoperative hypertension needed a vigilant follow-up especially in the wake-up period.

Lithium Intoxication Accompanied by Hyponatremia.

Lithium is frequently used in the management of bipolar affective disorders. It has a narrow therapeutic index and can cause acute or chronic intoxication. Toxic symptoms may be present even when concentrations are within the recommended therapeutic range. We believe that lithium intoxication is a very important issue for a physician. In this report, we aimed to evaluate the pathophysiological view of two chronic lithium intoxication cases accompanied by hyponatremia.

Postoperative analgesia for supratentorial craniotomy.

OBJECTIVES: The prevalence of moderate to severe pain is high in patients following craniotomy. Although optimal analgesic therapy is mandatory, there is no consensus regarding analgesic regimen for post-craniotomy pain exists. This study aimed to investigate the effects of morphine and non-opioid analgesics on postcraniotomy pain. PATIENTS AND METHODS: This prospective, randomized, double blind, placebo controlled study included eighty three patients (ASA 1, II, and III) scheduled for elective supratentorial craniotomy. Intravenous dexketoprofen, paracetamol and metamizol were investigated for their effects on pain intensity, morphine consumption and morphine related side effects during the first 24h following supratentorial craniotomy. Patients were treated with morphine based patient controlled analgesia (PCA) for 24h following surgery and randomized to receive supplemental IV dexketoprofen 50mg, paracetamol 1g, metamizol 1g or placebo. The primary endpoint was pain intensity, secondary endpoint was the effects on morphine consumption and related side effects. RESULTS: When the whole study period was analyzed with repeated measures of ANOVA, the pain intensity, cumulative morphine consumption and related side effects were not different among the groups (p>0.05). CONCLUSION: This study showed that the use of morphine based PCA prevented moderate to severe postoperative pain without causing any life threatening side effects in patients undergoing supratentorial craniotomy with a vigilant follow up during postoperative 24h. Although we could not demonstrate statistically significant effect of supplemental analgesics on morphine consumption, it was lower in dexketoprofen and metamizol groups than control group.

Intensive Care Treatment in Traumatic Brain Injury.

Head injury remains a serious public problem, especially in the young population. The understanding of the mechanism of secondary injury and the development of appropriate monitoring and critical care treatment strategies reduced the mortality of head injury. The pathophysiology, monitoring and treatment principles of head injury are summarised in this article.