Analgesia Nociception Index (ANI) as a monitor of peri-operative nociception-antinociception balance in paediatric craniotomies: a prospective observational study.

INTRODUCTION: Analgesia Nociception Index (ANI) as a monitor of peri-operative nociception-anti-nociception balance has not been studied in paediatric neurosurgery. The objectives were to study the correlation between ANI (Mdoloris Education system) and revised FLACC (r-FLACC) score for the prediction of acute postoperative pain in paediatric population undergoing elective craniotomies and to compare the changes in ANI values with heart rate (HR), mean arterial pressure (MAP) and surgical plethysmographic index (SPI) during various time points of intraoperative noxious stimulation and before and after opioid administration. METHODS: This prospective observational pilot study included 14 patients between 2 and 12 years of age undergoing elective craniotomies. HR, MAP, SPI, ANI instantaneous (ANIi) and ANI mean (ANIm) values were recorded intraoperatively and before and after opioid administration. Postoperatively HR, MAP, ANIi and ANIm, and pain scores (r-FLACC scale) were recorded. RESULTS: There was a statistically significant negative correlation between ANIi and ANIm with r-FLACC during the time course of PACU stay (r = - 0.89, p < 0.001 and r = - 0.88 and p < 0.001 respectively). Intraoperatively, in patients with ANIi values < 50, with additional fentanyl administration, there was an increasing trend in values beyond 50, which was statistically significant (p < 0.05) at 3, 4, 5 and 10 min. The trend in changes of SPI after opioid administration was not found to be significant for patients irrespective of the baseline SPI values. CONCLUSION: The ANI is a reliable tool for objective assessment of acute postoperative pain as assessed by r-FLACC in children undergoing craniotomies for intracranial lesions. It may be used as a guide to nociception-antinociception balance during the peri-operative period in this population.

Postoperative delirium after intracranial neurosurgery: A prospective cohort study from a developing nation.

INTRODUCTION: Post-operative delirium (POD) is a major complication after anesthesia and surgery with an incidence varying from 5 to 50%. The incidence of POD after intracranial surgery is likely to be higher due to the pre-existing brain pathology and direct handling of the brain during neurosurgery. The primary objective of this study was to assess the incidence of POD after intracranial neurosurgery and our secondary objective was to identify the potential risk factors for its occurrence. MATERIALS AND METHODS: This prospective observational study was conducted after the institutional ethics committee approval between october 2020 and march 2021. We included patients of either gender aged ≥ 18 years and undergoing elective intracranial neurosurgery. Exclusion criteria included patients aged below 18 years, undergoing emergency neurosurgery, patients with impaired consciousness and patients with psychiatric comorbidities or those taking psychotropic medications. We planned to exclude patients from analysis who were transferred to intensive care unit (ICU) or if they were not extubated after surgery. Our study outcome was development of POD as assessed by confusion assessment method (CAM). RESULTS: The overall incidence of POD during the three postoperative days was 19.2% (n=60/313). The incidence of POD on days 1, 2, and 3 were 19.2% (n=60/313), 17.2% (n=50/291), and 16.3% (n=39/239). Preoperative delirium and hyperactive Emergence Delirium were found to be the significant predictors of POD. CONCLUSION: Every one in five patients undergoing intracranial neurosurgery is vulnerable for the development of POD within first three days after surgery. The incidence of occurrence of POD is time-sensitive and is decremental.

Preoperative assessment of optic nerve sheath diameter and heart rate variability to predict intraoperative brain condition in patients with supratentorial tumors: a prospective observational study.

Brain relaxation is an important requirement in intracranial neurosurgical procedures and optimal brain relaxation improves the operating conditions. Optic nerve sheath diameter (ONSD) is a non-invasive bedside surrogate marker of intracranial pressure (ICP) status. Elevated ICP is often associated with marked autonomic dysfunction. There is no standard measure to predict intraoperative brain condition non-invasively, considering both anatomical displacement and physiological effects due to raised ICP and brain oedema. This study was aimed to determine the usefulness of heart rate variability (HRV) parameters and ONSD preoperatively in predicting intraoperative brain relaxation in patients with supratentorial tumors undergoing surgery.This prospective observational study was conducted in a tertiary care centre. 58 patients with supratentorial brain tumors undergoing elective surgery were studied. Preoperative clinical presentation, computed tomography (CT) findings, ONSD and HRV parameters were assessed in determining intraoperative brain condition. Intraoperative hemodynamic parameters and brain relaxation score after craniotomy were studied. There was significant difference in CT grade, ONSD and HRV parameters in patients between lax and tight brain. A receiver operating curve was constructed to determine the cut off to predict intraoperative brain bulge. A CT grade more than 2, ONSD of greater than 0.63 cms and ratio of low frequency to high ratio (LF/HF) of more than 1.8 were good predictors of brain bulge. The changes in ONSD and HRV parameters, with the CT findings can be used as surrogate markers of increased ICP to help predict intraoperative brain condition.

Perioperative care practices and outcomes of intracranial neurosurgery: Experience at a dedicated neurosciences hospital in a developing country.

Background and Aims: Understanding of perioperative care practices and early postoperative outcomes helps minimize potentially preventable perioperative complications while supporting systemic and neurological well-being. The objective of this prospective study was to evaluate the perioperative care practices and early postoperative outcomes of cranial neurosurgery at a high-volume tertiary care neurosciences hospital in India. We also aimed to see if the care elements differed depending on the surgical approach. We hypothesized that care elements and outcomes are likely to be different between major surgical approaches. Material and Methods: This was a prospective observational study of consecutive adult neurosurgical patients who underwent elective surgeries for intracranial pathologies over a period of six months from October 2020 to March 2021 at a tertiary care neurosciences center in India. Perioperative data about intraoperative care elements and early postoperative outcomes till the third day after surgery were collected. Results: Incidence of blood loss >1 L was significantly (P = 0.07) higher after infratentorial surgery (26%, N = 17). Incidence of intraoperative and postoperative desaturation was more after transnasal surgery (6%, N = 2, P = 0.002, and 9%, N = 3, P = 0.01, respectively). Conclusion: This study informs the early perioperative care practices of neurosurgical patients from a dedicated neurosciences hospital in a developing world. We observed that transnasal surgery was associated with more perioperative adverse events and slower convalescence compared to supra- and infratentorial surgeries despite being a considerably less invasive surgery.

Ultrasonographic evaluation of lung and heart in predicting successful weaning in mechanically ventilated neurosurgical patients.

In critically ill neurosurgical patients, delayed and premature extubation increases the risk of morbidity and mortality. Assessment of critically ill patients before and during spontaneous breathing trial (SBT) is crucial in predicting weaning failure. We explored the trend of changes with integrated lung and cardiac ultrasonography in predicting success of weaning in neurosurgical patients. Lung ultrasound and cardiac ultrasound was performed before and after 30 min and 120 min of SBT. Lung ultrasound score (LUS, range 0-36) was calculated using a predefined method of assessment of six chest regions on either side. The left ventricular function was evaluated by measuring fractional area change. The maximum velocities of mitral inflow E and A waves (E/A), deceleration time of E wave (DTE) and tissue doppler based E' wave at lateral annulus to calculate E/E', were measured to assess left ventricular filling pressure. Twenty seven patients underwent SBT, among these 22 had success and five had failure of SBT. The SBT failure group had higher baseline LUS and progressively higher LUS during SBT compared to the success group, suggesting significant lung de-recruitment. There was significant increase in the LV filling pressure (increase E/A and E/E', decrease in DTE) after 30 and 120 min of SBT in failure group compared to the success group. Point of care lung and cardiac ultrasonography may be useful in detecting cardiopulmonary changes induced by SBT. Higher lung aeration loss and LV filling pressure were observed with SBT failure group.

Fall in inspired oxygen and anaesthetic agent concentrations during change of soda lime absorber.

Following an episode of reduction in inspired oxygen concentration (FiO(2)) and inhalational agent concentration (Fi agent) during the changing of a soda lime absorber, We conducted an in vitro experiment to understand the impact of disconnection of the absorber on inspired gas dilution at different fresh gas flows. We found that both in Dräger Fabius GS and Primus anaesthesia work stations, disconnection of the absorber caused progressive reduction in FiO(2) and Fi agent as the FGF was decreased. The operating principle of fresh gas decoupling (FGD) valve is a potential source of this complication, which must be kept in mind while changing the soda lime during the course of surgery where an anaesthetic work stations utilizing FGD valves are used.

Low-Flow Anesthesia, Low Fresh Gas Flow, and Oxygen Flush: An Interesting Interplay.

Identification and analysis of critical respiratory alarms during use of an advanced anesthesia workstation is essential in the intraoperative period. We present and discuss a scenario in which there was activation of a fresh gas flow alarm during low-flow anesthesia intraoperatively and use of oxygen flush to counteract it led to a diluted concentration of the inspired anesthetic agent.

Incidence, predictors, and impact of acute post-operative pain after cranial neurosurgery: A prospective cohort study.

Objectives: Pain is common after craniotomy. Its incidence and predictors in developing nations are not adequately studied. We aimed to assess the incidence, predictors, and impact of acute post-operative pain after intracranial neurosurgeries. Materials and Methods: This prospective observational study was conducted in adult patients undergoing intracranial neurosurgeries. After patient consent, ethics committee approval, and study registration, we assessed the incidence of post-operative pain using numerical rating scale (NRS) score. Predictors and impact of pain on patient outcomes were also evaluated. Results: A total of 497 patients were recruited during 10-month study period. Significant (4-10 NRS score) post-operative pain at any time-point during the first 3 days after intracranial neurosurgery was reported by 65.5% (307/469) of patients. Incidence of significant pain during the 1st post-operative h, on the 1st, 2nd, and 3rd post-operative days was 20% (78/391), 50% (209/418), 38% (152/401), and 24% (86/360), respectively. Higher pre-operative NRS score and pain during the 1st h post-operatively, predicted the occurrence of pain during the first 3 days after surgery, P = 0.003 and P < 0.001, respectively. Pain was significantly associated with poor sleep quality on the first 2 post-operative nights (P < 0.001). Patient satisfaction score was higher in patients with post-operative pain, P = 0.002. Conclusion: Every two in three patients undergoing elective intracranial neurosurgery report significant pain at some point during the first 3 postoperative days. Pre-operative pain and pain during 1st post-operative h predict the occurrence of significant post-operative pain.

Outcome Prediction of TBI: Are There Parameters That Affect the IMPACT and CRASH Models?

BACKGROUND: Abnormal hematologic parameters associated with unfavorable neurological outcomes in traumatic brain injury (TBI) have been studied in isolation. We aimed to study whether there are any additional parameters that improve standard prognostic models in TBI. METHODS: This prospective observational study conducted in a tertiary neurological care center included adult patients with moderate and severe isolated head injury. Laboratory and clinical parameters were noted at admission, and the Glasgow Outcome Score-Extended of patients was assessed after 6 months. Multiple logistic regression was conducted using fixed coefficients of IMPACT (International Mission for Prognosis and Analysis of Clinical Trials) and CRASH (Corticosteroid Randomisation After Significant Head Injury) prognostic models. The new composite models were compared with the original models. RESULTS: The study comprised 96 patients. Parameters with relatively good predictability for mortality were elevated international normalized ratio (area under the curve [AUC] 0.69, odds ratio 13.2), total leukocyte count (AUC 0.68, odds ratio 1.15), and transfusion of blood products (AUC 0.72, odds ratio 6.43). Addition of these led to a statistically small improvement in predictions of IMPACT and CRASH. Neutrophil-to-lymphocyte ratio was not a good predictor of mortality or morbidity (AUC 0.58 and 0.47, respectively). CONCLUSIONS: International normalized ratio, total leukocyte count, and blood transfusion were found to be predictors of mortality and unfavorable neurological outcome in TBI at 6 months. Their addition to the IMPACT and CRASH prognostic models resulted in a modest improvement in the prediction of outcome in TBI.

Multimodal Intraoperative Monitoring During Microsurgical Treatment of Spinal Dural Arteriovenous Fistula.

We report here a case to illustrate the potential intraoperative multimodal monitoring options available for safe ligation of spinal dural arteriovenous fistula (DAVF). The success of microsurgical treatment depends on the correct identification of the arterial feeder and monitoring the functional integrity of the corticospinal tract.

Surgical outcomes in traumatic brain injuries with bilateral mass occupying lesions. Analysis of prognostic factors.

INTRODUCTION: Traumatic brain injury is a silent epidemic with major impacts on national productivity as it affects the economically productive age group. Bilateral injuries are usually severe with no clearly defined predictors of outcome as per current available literature. METHODS: We retrospectively assessed 102 consecutive cases of post traumatic intracranial mass lesions operated bilaterally, either simultaneously or sequentially, between January 2011 and April 2019. The primary and secondary end points of the study were to assess mortality and GCS at discharge respectively. RESULTS: The cohort included 102 patients. 91(89.2 %) were males, mean age was 40(±13.6) years. Median GCS at presentation was 9 with 47(46.07 %) having moderate head injury. EDH with contusion was seen in 38(37.3 %), SDH with contusion in 24(23.5 %) and 4 patients (3.9 %) had EDH, SDH and contusion. On univariate analysis, female gender(p = 0.001), poor GCS at presentation(p < 0.001), higher Rotterdam grade on initial CT scan(p < 0.001), need for blood transfusions(p = 0.026) and intraoperative hypotension(p = 0.007) were associated with significantly higher mortality. On multivariate analysis female gender(p = 0.034), poor GCS(p = 0.026) and worse Rotterdam score(p = 0.038) were associated with mortality. Among the subgroup of survivors, GCS at presentation(p < 0.001), Rotterdam grading(p = 0.003), time to surgery after trauma(p = 0.032), duration of hospital stay(<0.001), intraoperative brain bulge(p=.003) and craniotomy instead of craniectomy(p = 0.001) were associated with clinical outcome at discharge. CONCLUSION: Traumatic brain injuries with bilateral mass lesions requiring surgery have been rarely reported. In this study we have elucidated management strategies and have further studied the factors influencing mortality and clinical outcome. Careful considerations are required in decision making in such cases. Larger multicentric studies would throw more light on outcomes of this rare variety of traumatic brain injury.

Perioperative Factors Affecting Neurologic Outcome in Infants Undergoing Surgery for Intracranial Lesion: A Retrospective Study.

BACKGROUND: The short-term neurologic outcome of infants undergoing brain tumor surgery depends on various perioperative factors. This study was undertaken to analyze the effects of perioperative variables on the postoperative neurologic outcome in infants undergoing brain tumor surgery. METHODS: We retrospectively reviewed the chart of infants undergoing craniotomy for brain tumor removal from 2000 to 2017. The data related to preoperative variables, intraoperative management details, and postoperative factors were collected and analyzed. The primary outcome measure was occurrence of new postoperative neurologic deficit (POND) and the secondary outcome measure was length of hospital stay (LOHS). RESULTS: Complete data were available for 40 infants undergoing craniotomy for excision of intracranial tumor. New-onset POND was found in 14 infants (35%). Based on logistic regression analysis, POND was associated with use of mannitol and massive blood transfusion (MBT) trended toward significance. Based on linear regression analysis, the risk factor associated with prolonged LOHS was reintubation and POND trended toward significance. CONCLUSIONS: In this study, factors associated with new POND were mannitol use and to a certain extent MBT. The variables associated with prolonged LOHS were reintubation and to a certain extent POND. The anesthetic technique, location of tumor, tumor histology, and extent of tumor resection did not influence the occurrence of new POND or prolonged LOHS in infantile intracranial tumor surgery. Further prospective studies with larger samples are required for confirmation of these findings and identification of new perioperative risk factors.

An unusual cause of high peak airway pressure: Interpretation of displayed alarms.

Airway pressure monitoring is critical in modern day anesthesia ventilators to detect and warn high or low pressure conditions in the breathing system. We report a scenario leading to unexpectedly very high peak inspiratory pressure in the intraoperative period and describe the mechanism for high priority alarm activation. We also discuss the role of a blocked bacterial filter in causing sustained display of increased airway pressure. This scenario is a very good example for understanding the unique safety feature present in the Dräger ventilators and the attending anesthesiologist must have an adequate knowledge of the functioning and safety feature of the ventilators they are using to interpret the alarms in the perioperative to prevent unnecessary anxiety and intervention.