Non-opioid versus Opioid Peri-operative Analgesia In Neurosurgery (NOPAIN): Study protocol for a multi-centric randomised controlled trial.

Background and Aims: Many patients suffer from post-operative pain after neurosurgery despite using intra-operative opioids. Opioid side effects are problematic in neurosurgical patients. Hence, non-opioid alternatives for the management of nociception and pain are needed. Previous studies comparing opioids with non-opioids in the neurosurgical population were few, from single centres, of small sample sizes and were equivocal in findings, which prevented change in clinical practice. To overcome these limitations, we are conducting a multi-centre trial with objectives to compare intra-operative rescue opioid requirements and post-operative pain scores (primary objectives), adverse events, quality of recovery from anaesthesia, quality of sleep and patient satisfaction during hospital stay, and persistent post-surgical pain and quality of life at 3 and 6 months (secondary objectives) in patients receiving opioid and non-opioid analgesia for brain tumour surgeries. Methods: This study protocol describes the methodology of a multi-centre randomised controlled trial. Ethics committee approval has been obtained from all five centres, the trial has been registered with the Clinical Trial Registry- India, and insurance has been obtained for this investigator-initiated funded study. In patients undergoing supra-tentorial brain tumour surgery (population), we will compare fentanyl (intervention) 1 µg/kg/h with dexmedetomidine (comparator) 0.5 µg/kg/h administered during surgery with regards to intra-operative rescue opioid requirement and post-operative pain (primary outcomes). Results: We describe the study protocol of the multi-centre trial (protocol version 2, dated 29/01/2022). The first patient was recruited on 19/10/2022, and we will complete recruitment before March 2024. Conclusion: We expect our study to establish dexmedetomidine as an effective non-opioid analgesic vis-à-vis opioids in the neurosurgical population.

Effect of administration of tranexamic acid on blood loss and transfusion requirements in children undergoing posterior fossa tumor excision: a retrospective cohort study.

BACKGROUND: Surgical resection of posterior fossa tumors (PFT) in the pediatric age group often results in significant intraoperative blood loss. The primary objective was to assess the effect of tranexamic acid (TXA) on blood loss and transfusion requirement in pediatric patients undergoing excision of PFT. METHODS: In this retrospective study, all pediatric patients ≤ 18 years, who underwent PFT resection over a period of 7 years, were included. The patient and surgical characteristics, estimated blood loss (EBL), the need for blood and blood product transfusion, use of crystalloids, vasopressors, and any adverse events like seizures and thromboembolic events were recorded and compared between Group A who received TXA and Group B who did not. RESULTS: The study included 50 patients, out of which 36 belonged to Group A and 14 to Group B. The median age was 8 years (IQR, 2-17) and the mean BMI was 16.46 ± 4.11 kg/m2. The mean EBL was 224.29 ± 110.36 ml in group A (n = 36) and 362 ± 180.11 ml in group B (n = 14) (p = 0.007). The intraoperative volume of crystalloid use was significantly higher in group B (p = 0.04). The requirement of blood and blood product transfusion was similar between the groups, but the volume of blood transfusion per kg body weight was higher in group B, 8.3 (IQR, 6.7-11.1) ml/kg in Group A versus 10.5 (IQR, 8.1-16.1) ml/kg in Group B (p-value 0.3). The rates of complications noted in the form of seizures and thromboembolic events were comparable. CONCLUSION: The use of TXA in the pediatric population undergoing PFT resection aids in reducing blood loss during the surgery without increasing complications.

Relationship between pulse pressure variation and stroke volume variation with changes in cardiac index during hypotension in patients undergoing major spine surgeries in prone position - A prospective observational study.

Background and Aims: Dynamic indices such as pulse pressure variation (PPV) and stroke volume variation (SVV) are better predictors of fluid responsiveness than static indices. There is a strong correlation between PPV and SVV in the prone position when assessed with the fluid challenge. However, this correlation has not been established during intraoperative hypotension. Our study aimed to assess the correlation between PPV and SVV during hypotension in the prone position and its relationship with cardiac index (CI). Material and Methods: Thirty patients aged 18-70 years of ASA class I-III, undergoing spine procedures in the prone position were recruited for this prospective observational study. Hemodynamic variables such as heart rate (HR), mean arterial pressure (MAP), PPV, SVV, and CI were measured at baseline (after induction of anesthesia and positioning in the prone position). This set of variables were collected at the time of hypotension (T-before) and after correction (T-after) with either fluids or vasopressors. HR and MAP are presented as median with inter quartile range and compared by Mann-Whitney U test. Reliability was measured by intraclass correlation coefficients (ICC). Generalized estimating equations were performed to assess the change of CI with changes in PPV and SVV. Results: A statistically significant linear relationship between PPV and SVV was observed. The ICC between change in PPV and SVV during hypotension was 0.9143, and after the intervention was 0.9091 (P < 0.001). Regression of changes in PPV and SVV on changes in CI depicted the reciprocal change in CI which was not statistically significant. Conclusion: PPV is a reliable surrogate of SVV during intraoperative hypotension in the prone position.

A Randomised Control Study Comparing C-MAC D-Blade Video Laryngoscope (Hyper Angulated Blade) and Macintosh Laryngoscope for Insertion of a Double-Lumen Tube in Patients Undergoing Elective Thoracotomy.

Background: The use of a double-lumen endotracheal tube is one of the common anesthetic techniques for operations in the thoracic cavity. However, when compared to a single-lumen tube, placement of a double-lumen tube is technically more difficult as a result of which it takes more time to insert and is associated with more complications such as mucosal injury, hoarseness, and sore throat, even in patients with no anticipated airway difficulty. The CMAC D-blade that is usually used in patients with anticipated airway difficulty, could assist in smooth and quick placement of double-lumen tube (DLT) even in patients with no anticipated airway difficulty. Aim of the Study: This study aimed to evaluate the effectiveness of the C-MAC D-blade in reducing the time taken to visualize the glottis and intubate patients with normal airway with a double-lumen tube. Setting and Design: This was a prospective open-label randomized control trial in a tertiary hospital. Materials and Methods: Seventy-three consenting adult patients with physical status classes I and II, as determined by the American Society of Anesthesiologists, scheduled to undergo elective thoracotomy, were randomly allocated to receive either C-MAC D-blade (Group D) or Macintosh blade (Group M). The primary objective was to compare the time taken for visualization of the glottis and intubation. Statistical Analysis Used: Chi-square/Fisher's exact test and t-test were used for statistical analysis. Results: Seventy-three patients were randomized (Group D = 36; Group M = 37). Time to visualize the glottic structures (4.56 ± 2.396 s vs. 7.27 ± 4.891 s, P = 0.01) was significantly better in Group D; however, the mean intubation time was comparable (55.92 ± 18.749 s vs. 51.08 ± 15.269 s, P = 0.61). Conclusion: C-MAC D-blade videolaryngoscope offers a better glottic view and lesser time to visualize glottis when compared with the Macintosh laryngoscope. However, the time taken to insert the DLT after visualization was longer. We infer that there is no advantage in the routine use of C-MAC D-blade for DLT insertion in patients with no anticipated airway difficulty.

Feasibility and diagnostic accuracy of intra-operative monitoring of motor evoked potentials in children <2 years of age undergoing tethered cord surgery: results in 100 children.

OBJECTIVE: This study documents the monitorability using different anesthesia regimes and accuracy of muscle motor evoked potentials (mMEPs) in children ≤2 years of age undergoing tethered cord surgery (TCS). METHODS: Intraoperative mMEP monitoring was attempted in 100 consecutive children, ≤2 years of age, undergoing TCS. MEP monitoring was done under 4 different anesthetic regimes: (Total intravenous anesthesia (TIVA); balanced anesthesia with sevoflurane and ketamine; balanced anesthesia with isoflurane and ketamine; and balanced anesthesia with sevoflurane). Factors analyzed for their effect on monitorability were: age, neurological deficits, type of anesthesia, and the number of pulses used for stimulation. RESULTS: Baseline mMEPs were obtained in 87% children. Monitorability of mMEPs was similar in children ≤1 year and 1-2 years of age (85.7% and 87.5%). In multivariate analysis, anesthesia regime was the only significant factor predicting presence of baseline mMEPs. Children undergoing TIVA (p=0.02) or balanced anesthesia with a combination of propofol, sevoflurane, and ketamine (p=0.05) were most likely to have baseline mMEPs. mMEPs had a sensitivity of 97.4%, specificity of 96.4%, negative predictive value of 98.2% and accuracy of 96.8%. CONCLUSIONS: Baseline mMEPs were obtained in >85% of children ≤2 years of age including those who had motor deficits. TIVA and balanced anesthesia with sevoflurane and ketamine are ideal for mMEP monitoring. mMEPs have a high accuracy although, false positive and false negative results can occasionally be experienced.

A Prospective Randomized Trial Comparing Topical Intranasal Lidocaine and Levobupivacaine in Patients Undergoing Endoscopic Binostril Transnasal Transsphenoidal Resection of Pituitary Tumors.

INTRODUCTION: Local anesthetic intranasal packing is used in transnasal surgery to reduce hemodynamic fluctuations. We hypothesized that the long acting local anesthetic levobupivacaine would provide superior hemodynamic stability and postoperative analgesia compared with lidocaine in endoscopic transnasal transsphenoidal (TNTS) surgery. MATERIALS AND METHODS: In this prospective, randomized, double-blind trial, 48 patients undergoing TNTS surgery were allocated to the 2 groups to receive preoperative intranasal packing with 15 mL of 1.5% lidocaine or 0.5% levobupivacaine each mixed with 60 mg ephedrine. Heart rate and mean arterial blood pressure were recorded immediately before induction of anesthesia, at various time points throughout surgery, and at tracheal extubation. Bleeding in the surgical field, time to extubation, and postoperative pain were also assessed. RESULTS: There was no significant difference in heart rate between the lidocaine and levobupivacaine groups at any point. Mean arterial pressure was also similar between the 2 groups during surgery, whereas at extubation blood pressure was lower in the lidocaine compared with levobupivacaine group (85±10 vs. 96±16 mm Hg; P=0.0010). There were no differences between the 2 groups in the other outcome variables. CONCLUSIONS: Preoperative intranasal packing with 1.5% lidocaine or 0.5% levobupivacaine provide similar hemodynamic stability throughout TNTS. Lidocaine packing may be more advantageous for hemodynamic stability during extubation.

Changes in central venous oxygen saturation, lactates, and ST segment changes in a V lead ECG with changes in hemoglobin in neurosurgical patients undergoing craniotomy and tumor excision: A prospective observational study.

BACKGROUND AND AIMS: The aim of the study was to observe the trends in central venous oxygen saturation (ScvO2), lactate, and ST segment changes with change in hemoglobin in patients undergoing acute blood loss during surgery and to assess their role as blood transfusion trigger. MATERIAL AND METHODS: Seventy-seven consecutive patients undergoing craniotomy at a tertiary care institution were recruited for this study after obtaining written, informed consent. After establishing standard monitoring, anesthesia was induced with standard anesthetic protocol. Hemodynamic parameters such as heart rate, blood pressure (mean, systolic, diastolic), pulse pressure variation (PPV), and physiological parameters such as lactate, ScvO2, ST segment changes were checked at baseline, before and after blood transfusion and at the end of the procedure. STATISTICAL ANALYSIS: Comparison of the mean and standard deviation for the hemodynamic parameters was performed between the transfused and nontransfused patient groups. Pearson correlation test was done to assess the correlation between the covariates. Receiver operating characteristic (ROC) curve was constructed for the ScvO2 variable, which was used as a transfusion trigger and the cutoff value at 100% sensitivity and 75% specificity was constructed. Linear regression analysis was done between the change in hemoglobin and the change in ScvO2 and change in hemoglobin and change in the ST segment. RESULTS: There was a statistically significant positive correlation between the change in ScvO2 and change in hemoglobin during acute blood loss with a regression coefficient of 0.8 and also between change in ST segment and hemoglobin with a regression coefficient of -0.132. No significant change was observed with lactate. The ROC showed a ScvO2 cutoff of 64.5% with a 100% sensitivity and 75% specificity with area under curve of 0.896 for blood transfusion requirement. CONCLUSIONS: We conclude that ScvO2 and ST change may be considered as physiological transfusion triggers in patients requiring blood transfusion in the intraoperative period.

A randomized controlled trial to determine the role of intraoperative lumbar cerebrospinal fluid drainage in patients undergoing endoscopic transsphenoidal surgery for pituitary adenomas.

BACKGROUND: Intraoperative cerebrospinal fluid (CSF) leaks are a frequent cause of morbidity in patients undergoing transsphenoidal surgery. This prospective study was performed to examine the impact of intraoperative lumbar subarachnoid drainage (LSAD) on the incidence of this complication and on the extent of resection in patients undergoing endoscopic transsphenoidal surgery for pituitary adenomas. MATERIALS AND METHODS: This prospective study was conducted in a single large academic medical center. All patients with pituitary adenomas who had not undergone prior transsphenoidal surgery were eligible for inclusion in the study. Patients were randomly assigned to undergo transsphenoidal surgery with intraoperative lumbar drain insertion (LSAD group) or no lumbar drain insertion (no LSAD group). An otolaryngologist independently determined the occurrence of an intraoperative CSF leak. Extent of tumor resection was determined by volumetric analysis of postoperative magnetic resonance images in patients with nonfunctional tumors or functional adenomas with a large suprasellar component. RESULTS: Sixty patients were eligible for inclusion, of which 30 were assigned to the LSAD group and 30 to the no LSAD group. There were no statistically significant differences in patient demographics, tumor pathology, or radiology between the two groups. The LSAD catheter was successfully inserted in all patients in the LSAD group. Intraoperative CSF drainage significantly reduced the incidence of CSF leak from 46.7% in the no LSAD group to 3.3% in the LSAD group (P < 0.001). However, there were no statistically significant differences in the incidence of postoperative CSF rhinorrhea between the two groups. There were no major catheter-related complications. There was no statistically significant difference in the extent of resection between the two groups. CONCLUSIONS: Controlled intraoperative CSF drainage significantly reduces the incidence of intraoperative CSF leakage in patients undergoing endoscopic transsphenoidal surgery for pituitary adenomas.