Limitations of near infrared spectroscopy (NIRS) in neurosurgical setting: our case experience.

One of the primary goals of anaesthesia in neurosurgical procedures is prevention of cerebral hypoxia leading to secondary neurological injury. Cerebral oximetry detects periods of cerebral hypoxemia and allows intervention for prevention of secondary brain injury and its sequelae. This can be achieved by the use of Near Infrared Spectroscopy (NIRS). In this regard, we present two cases where erroneous values of NIRS were shown which hindered monitoring of cerebral oxygenation in the intraoperative setting. In a neurosurgical setting, the erroneous values on the operative side could be attributed to altered tissue boundary conditions resulting in a changed optical path, which is normally held as a constant in NIRS measurements. The altered tissue boundary conditions could be due to the presence of air or blood between the myocutaneous flapskull, skull-dura, dura-brain interphases. It could also be that the sensors' penetrating depth was inadequate to compensate for the increased distance between sensor and brain tissue, thereby resulting in inaccurately higher values (> 80%).

Magnetic resonance imaging (MRI) induced 'hypoxia artifacts' on pulse oximetry: how reliable are MRI compatible monitoring devices?

Distinguishing a monitoring artifact requires expertise and adeptness. This can be practically challenging during the course of an anesthetic. We report a case, wherein we experienced episodes of aberrant pulse-oximeter values suggestive of desaturation with normal waveforms, occurring during a particular sequence of magnetic resonance imaging (MRI) performed under general anesthesia, which in fact was an artifact induced by the 3 T MRI during the diffusion tensor imaging sequence.

Seizures - just the tip of the iceberg: Critical care management of super-refractory status epilepticus.

Super-refractory status epilepticus (SRSE) is defined as status epilepticus (SE) that continues or recurs 24 h or more after the onset of anesthetic therapy, including those cases where SE recurs on the reduction or withdrawal of anesthesia. Although SRSE is a rare clinical problem, it is associated with high mortality and morbidity rates. This article reviews the treatment approaches and the systemic complications commonly encountered in patients with SRSE. As evident in our search of literature, therapy for SRSE and its complications have been based on clinical reports and expert opinions since there is a lack of controlled and randomized trials. Even though this complex condition starts as a neurological disorder, because of the associated systemic complications, it can be considered as a multisystem disorder requiring scrupulous attention and deliberate efforts to prevent, detect, and treat these systemic effects. We have critically reviewed the intensive care management for SRSE per se as well as its associated systemic complications. We believe that a good recovery can occur even after prolonged and severe SRSE as long as the systemic complications are detected early and managed appropriately.

Glycated hemoglobin A: A predictor of outcome in trauma admissions to intensive care unit.

BACKGROUND AND AIM: Although large studies have demonstrated the association between hyperglycemia and adverse intensive care unit (ICU) outcomes, it is yet unclear which subset of patients benefit from tight sugar control in ICU. Recent evidence suggests that stress induced hyperglycemia (SIH) and co-incidentally detected diabetes mellitus are different phenomena with different prognoses. Differentiating SIH from diabetic hyperglycemia is challenging in ICU settings. We followed a cohort of trauma patients admitted to a surgical intensive care unit (SICU) to evaluate if initial glycated hemoglobin A (HbA1c) level predicts the outcome of admission. MATERIALS AND METHODS: A cohort of 120 consecutive admissions to SICU following trauma were recruited and admission blood sugar and HbA1c were measured. Outcomes were prospectively measured by blinded ICU doctors. A logistic regression model was developed to assess if HbA1c predicts poor outcomes in these settings. RESULTS: Nearly 24% of the participants had HbA1c ≥ 6. Those with HbA1c ≥ 6 had 3.14 times greater risk of poor outcome at the end of hospital stay when compared to those with HbA1c < 6 and this risk increased to an odds ratio of 4.57 on adjusting for other significant predictors: Acute Physiology and Chronic Health Evaluation II, injury severity score, admission blood sugar and age at admission. CONCLUSIONS: Substantial proportion of trauma admissions has underlying diabetes. HbA1c, a measure of pre admission glycaemic status is an important predictor of ICU outcome in trauma patients.

Anatomical considerations of cutaneous nerves of scalp for an effective anesthetic blockade for procedures on the scalp.

Objective: The anatomy of the scalp nerves varies widely with age, race, and individuals of the same race and even within the same individual and hence need to be studied extensively to avoid complications and improve effectiveness during various surgical and anesthetic procedures of the scalp. Materials and Methods: Gross dissection was carried out on 11 cadavers (22 Hemifaces: 11 right and 11 left) with no obvious scalp deformities or surgeries. The distances of the supraorbital nerve (SON), supratrochlear nerve (STN), and greater occipital nerve (GON) from commonly used bony landmarks were measured. The branching pattern and presence of accessory notches/foramina were noted. Results: SON and STN were found almost midway and at the junction between medial and middle one-third of the line joining midline and lateral orbital margin, respectively. The distances of STN and SON from the midline were about ½ and 3/4th of the transverse orbital diameters of the individual. GON was found at the medial 2/5 and lateral 3/5 of the line joining inion to the mastoid. In 40.9% cases, SON gave three branches while STN and GON remained as single trunks in 77.27% and 40.0% cases, respectively. Accessory foramina/notches for SON and STN were found in 36.36% and 4.54% of the specimen, respectively. SON and STN remained lateral in the majority while GON ran medially to corresponding vessels. Conclusion: These parameters on the Indian population would give a comprehensive idea of the distribution of these cutaneous scalp nerves and would be beneficial in the targeted and accurate deposition of local anesthetic.

Lumbar Erector Spinae Plane Block for Posterior-Superior Iliac Spine Bone Graft Site Pain in Patients Undergoing Occipitocervical and C1-C2 Fusion for Atlantoaxial Dislocation/Odontoid Fracture-A Case Series.

Pain at the autologous bone graft site from the posterior-superior iliac spine (PSIS) is severe enough to affect the postoperative ambulation. It adds to the morbidity of the surgical procedure. Inadequate pain management at the graft site not only affects the postoperative recovery but also can lead to chronic pain. We report the use of ultrasound (US)-guided lumbar erector spinae plane block (ESPB), to deliver effective analgesia for this pain. Patients who underwent occipitocervical fusion (OCF) and C1-C2 fusion using PSIS for atlantoaxial dislocation (AAD)/odontoid fracture from January to March 2020 and who received US-guided lumbar ESPB were retrospectively studied. All the necessary data were collected from the inpatient hospital, anesthesia, and the acute pain service records. A total of six patients received lumbar ESPB, of which one received a single shot injection, and the rest five had a catheter placement for postoperative analgesia. The average volume of intraoperative and postoperative bolus was 27(range: 15-30) and 21 (range: 15-30) mL of 0.2% ropivacaine, respectively. All patients achieved a unilateral sensory blockade ranging from L1 to L3 dermatomes. None of our patients had a numerical rating scale of > 4 on movement at any time point during the first 48 hours except in one, in whom only a single shot bolus was given. No complications related to ESPB were noted. All were ambulated on the second postoperative day except one. The average length of hospital stay was 6 (range: 4-10) days. US-guided lumbar ESPB provides excellent analgesia for PSIS bone graft site pain and promotes early ambulation.

Efficacy of Clonidine as an Additive on the Duration of Action of Brachial Plexus Block Performed Under Ultrasound and Nerve Locator Guidance: A Prospective Randomized Study.

BACKGROUND: Clonidine, an alpha2 agonist, when added to local anesthetics in different regional and neuraxial blocks reduces the onset time, improves the efficacy, and increases the duration of postoperative analgesia. AIMS: This study evaluated the effect of bupivacaine clonidine combination in ultrasound and nerve locator-guided supraclavicular brachial plexus block for upper limb surgeries. SETTINGS AND DESIGN: This was a prospective, randomized, controlled, double-blind study carried out in a tertiary care center in South India on 50 patients with American Society of Anesthesiologists (ASA) physical status classes I and II undergoing elective upper limb surgery under supraclavicular brachial plexus block. MATERIALS AND METHODS: Eligible participants were randomized equally to either Group B who received 20 ml of bupivacaine and 7 mL of 2% lignocaine or Group C who received 20 ml of bupivacaine, 7 ml of 2% lignocaine, and 100 µg of clonidine. STATISTICAL ANALYSIS: Continuous outcome variables were tested for statistical significance using Student's t-test, and Mann-Whitney U-test was used for outcomes that were nonnormally distributed. Categorical variables were compared using Fisher's exact test. P <0.05 was considered as statistically significant. RESULTS: The onset of sensory and motor blockade was significantly faster (P < 0.05) in Group C compared to Group B. The duration of sensory and motor block and the duration of analgesia were significantly longer in Group C (P < 0.001). The sedation in Group C patients was significantly more (P < 0.05) when compared to Group B, but none of the sedation scores exceeded 3 on the Ramsay sedation score. Hemodynamic parameters did not differ between groups (P > 0.05). CONCLUSION: The inclusion of 100 µg of clonidine with bupivacaine in ultrasound-guided supraclavicular brachial plexus blocks prolongs both sensory and motor blockade. It also provides significant postoperative analgesia and mild sedation which is beneficial in the immediate stressful postoperative period.

Anaesthetic Challenges in a Rare Syndrome: Perioperative Management of a Patient with POEMS Syndrome Who Underwent Umbilical Hernioplasty.

Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome also known as 'Crow Fukase syndrome' is a rare paraneoplastic disorder, first described by Crow and Fukase with distinctive features of polyradiculoneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and skin changes. There is a paucity of literature about anaesthetic management of patients with POEMS syndrome with isolated case reports of surgery under general anaesthesia and central neuraxial blockade. We present here the anaesthetic management of a patient with POEMS syndrome posted for umbilical hernia repair, which was successfully managed with a transverse abdominis plane (TAP) block.

Effect of Pregabalin on Perioperative Headache in Patients with Aneurysmal Subarachnoid Hemorrhage: A Randomized Double-Blind, Placebo-Controlled Trial.

Background Patients with acute aneurysmal subarachnoid hemorrhage (aSAH) experience excruciating headache that is difficult to manage in resource-constrained settings. Pregabalin's (ß-isobutyl-GABA) analgesic, antiepileptic, and antiemetic properties make it an attractive adjuvant in pain management for these patients. Methods We conducted a double-blind, placebo-controlled, randomized clinical trial on 40 aSAH patients undergoing aneurysmal clipping to assess the effect of perioperative pregabalin in decreasing perioperative headache, anesthetic, and opioid requirement. Patients received either pregabalin (75 mg) or placebo twice daily soon after admission till 24-hour postoperative, in addition to paracetamol 650 mg thrice daily. Headache assessed using a visual analog scale (VAS) at five time points was compared using a mixed effects regression model. Results Pain assessed by VAS declined significantly more from the baseline in pregabalin recipients compared with placebo at preinduction (-3.6 vs.-1.8; p = 0.004), 12-hour (4.3 vs. 2.8; p = 0.014), and 24-hour postsurgery (4.7 vs. 2.9; p = 0.007), but not at the 6-hour postoperation (4.9 vs. 3.8; p = 0.065). Pregabalin recipients required a lower minimum alveolar concentration of sevoflurane to maintain a prespecified bispectral index of 40 and 60 (0.8 vs. 0.9; p = 0.014) and required fewer rescue analgesic doses in the 24  hours following surgery (1.8 vs. 3.3; p = 0.005). The intraoperative fentanyl requirement was not significantly different between the groups (10 µg/kg vs. 11.4 µg/kg; p = 0.065). There was no significant difference in the sedation scores. Conclusions Pregabalin 75 mg administered twice daily, during the perioperative period, was an effective adjunct in the management of the severe headache experienced by patients with aSAH and decreased the opioid and anesthetic requirement without significantly increasing sedation.

A Study Comparing Propofol Auto-coinduction and Standard Propofol Induction in Patients Undergoing General Anesthesia Without Midazolam Pretreatment: A Prospective Randomized Control Trial.

BACKGROUND: Propofol has emerged as an induction agent of choice over the past two decades due to its quick, smooth induction and rapid recovery. The main concern for an anesthesiologist is the hemodynamic instability caused by the standard induction dose of propofol (2-3 mg/kg). AIM: We aim to study the efficacy of propofol auto-coinduction technique in comparison to the standard propofol induction technique in terms of the total induction dose requirement of propofol, the incidence of hemodynamic side effects and pain on injection, and the incidence of fentanyl-induced cough (FIC) in the absence of a synergistic agent like midazolam. MATERIALS AND METHODS: This was a prospective, observer-blinded, randomized controlled trial. The study was initiated after obtaining the institutional ethics committee approval and is registered in the Clinical Trials Registry India. Eighty American Society of Anesthesiology Physical Status I and II patients, of either sex, aged between 18 and 55 years, and scheduled for elective surgeries under general anesthesia were randomized into two equal groups. Patients allocated to Group I (auto-coinduction) received 20% of the calculated dose of injection propofol 2 mg/kg (i.e., 0.4 mg/kg) as the priming dose followed by injection fentanyl 1 µg/kg after 1 min and the remaining propofol was administered in titrated doses till loss of verbal response after 2 min. In Group II (control), patients received injection fentanyl 1 µg/kg followed by single bolus dose of injection propofol up to 2 mg/kg till loss of verbal response. Midazolam was not used for premedication or induction. Intubation was carried out only after ensuring achievement of optimum depth of anesthesia using bispectral index scale. The total dose of propofol administrated for induction, occurrence of pain on injection, severity of cough after fentanyl administration, hemodynamic parameters, and apneic episodes were recorded. STATISTICAL ANALYSIS: All data were expressed as mean ± 2 standard deviation. For statistical analysis, SPSS software version 16 (SPSS Inc., 2007, Chicago, IL, USA) was used. RESULTS: The mean dose of injection propofol required for induction was significantly lower in Group I (67.0 ± 17.9 mg) when compared with Group II (111.3 ± 17.6 mg) (P < 0.01). The mean heart rate was significantly higher (P < 0.01) and the mean blood pressure was significantly lower in Group II (P < 0.01) when compared to Group I at 1 min postinduction, immediately after intubation, and 5 min after induction. The incidence of complications such as hypotension, pain on injection, and FIC was higher in Group II (50%) as compared to Group I (18%). CONCLUSION: In our study, we found that the induction dose requirement of propofol was significantly lower in the auto-coinduction group when compared to the conventional induction group. The auto-coinduction technique offered a stable hemodynamic profile, reduced pain on injection, and less incidence of FIC as compared to the conventional propofol induction technique.

Periprocedural Management of Vein of Galen Aneurysmal Malformation Patients: An 11-Year Experience.

CONTEXT: The vein of Galen aneurysmal malformation (VGAM) is a rare arteriovenous malformation where a dilated median prosencephalic vein provides a low-resistance conduit for intracerebral blood flow resulting in high-output cardiac failure, severe pulmonary hypertension, with or without central nervous system symptoms secondary to hydrocephalus, in the neonatal and pediatric population. AIM: This study aims to analysis of the anesthetic management of this unique subset of patients with VGAM. SETTINGS AND DESIGN: This was a retrospective analysis of case series of VGAM patients admitted between January 2005 and June 2016 in our Institute. SUBJECTS AND METHODS: Case records of VGAM patients were reviewed for the anesthetic technique and medications administered. The incidence of intra-and post-procedural complications and their management and outcomes were analyzed. STATISTICAL ANALYSIS: Parametric data were expressed as mean and standard deviation. Descriptive statistics was used for describing associated pathologies, drugs and monitors used during the procedure, incidence of any adverse events, and the treatment protocol. RESULTS: Twenty-one patients underwent treatment for the VGAM. There were a total of forty anesthetics administered for embolization, diagnostic angiography, and magnetic resonance imaging. Eighty-five percent had increased head circumference, 40% had associated focal neurological deficits, and 15% had seizures as presenting symptoms. Cardiac anomalies were seen in 41% of the patients, and difficult airway was anticipated in 38% of the patients. The majority of the patients had inhalational induction (62.2%) and inhalation maintenance (84.4%) of anesthesia. Intraprocedural adverse events were noted in 43% and postprocedure complications in 38% of the patients. CONCLUSION: Anesthetic management for embolization of VGAM with a combination of opioids and inhalational agents helps in minimizing the incidence of intraprocedural adverse events and provides a better hemodynamic profile.