Comparison of nebulisation 0.75% ropivacaine with 2% lignocaine for attenuation of haemodynamic response due to intubation: A prospective randomised study.

INTRODUCTION: Laryngoscopy and intubation are associated with the reflex response of hypertension, tachycardia and other intraoperative complications. Nebulised route drug administration and entropy-guided induction enable optimal intubating conditions. AIMS: To compare pre-induction nebulisation between 0.75% ropivacaine and 2% lignocaine in blunting the nasotracheal intubation response. MATERIALS AND METHODS: A total of 100 patients undergoing elective faciomaxillary surgeries were prospectively randomised to receive pre-induction nebulisation: 5mL of 2% lignocaine (100mg) (Group L) or 5mL of 0.75% ropivacaine (37.5mg) (Group R). Patients were induced and intubated (nasotracheal) with entropy monitoring. Observed parameters included systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, entropy at baseline, induction, intubation, post-intubation one, three and five minutes, propofol induction dose, electrocardiogram changes and peri-intubation cough reflex. RESULTS: Ropivacaine aerosol proved significantly better than lignocaine aerosol on haemodynamics (systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate) and cough reflex (p < 0.05). Both groups experienced similar entropy changes and propofol induction dose requirements and no fresh electrocardiogram changes (compared with the baseline). CONCLUSION: Pre-induction nebulised ropivacaine offers superior intubating conditions than lignocaine regarding haemodynamic response and cough reflex for faciomaxillary surgeries.

Effect of etomidate and propofol on airway mechanics during induction - A prospective randomized trial.

Background and Aims: Intravenous induction agents like propofol and etomidate change the airway mechanics and thus influence mask ventilation. These changes have an impact on the administration of muscle relaxant in a difficult mask ventilation scenario. The difference in dynamics of airway after administration of two different intravenous agents has been assessed in this study. Material and Methods: After formal registry in clinical trials, patients undergoing general anesthesia were recruited and randomized into group P and E. Patients were induced with either of the intravenous agents, and mask ventilation was performed with a ventilator. After 60 s, rocuronium was administered and ventilation continued. Measurements of tidal volume, peak airway pressure, and compliance were taken from the anesthesia ventilator at different time points - induction, relaxant, and intubation. Results: There was no statistically significant difference between the two groups with respect to demographics, airway parameters, and airway mechanics, as measured by tidal volume, peak airway pressure, and lung compliance. There was an improvement in the tidal volume and compliance following induction with propofol, with a P value of 0.007 and 0.032, respectively, obtained in within-group comparison. Conclusion: Propofol and etomidate were comparable in airway mechanics, but compliance and tidal volumes improved with propofol, which facilitated face mask ventilation.

Comparison of median and paramedian technique of thoracic epidural anaesthesia in patients undergoing laparotomy under combined general and epidural anaesthesia - A prospective observational study.

Background and Aims: Most studies have found that lumbar epidural catheterisation is technically easier with a paramedian than median approach. There is scant literature comparing the two approaches to the epidural space in the mid-thoracic spine. This study aims to compare the median versus paramedian approaches in the location of epidural space in the T7-9 region in patients undergoing laparotomy under combined general and epidural anaesthesia. Methods: A prospective observational study was conducted after ethical approval and written informed consent on 70 patients undergoing major abdominal surgery. The patients received epidural analgesia either through a median or paramedian approach (Group M, n = 35 and Group P, n = 35). The primary objective was the incidence of successful epidural catheter placement in the first attempt. The secondary objectives were the overall success rate, the requirement of change of intervertebral space, approach or operator and complications associated with the procedure. Results: Sixty-seven patients were analysed. Epidural catheter was placed successfully in the first attempt in 40% of patients in Group M and 78.1% in Group P (P = 0.003). The overall success rate was 74.3% in Group M and 87.5% in Group P (P = 0.223). The number of attempts in Group M was more (one attempt 14, two 6, three 5 and four 1) as compared to Group P (one 25, two 2, three 1 and four 0) (P = 0.014). The incidence of complications was comparable between the groups. Conclusion: Epidural catheter insertion was technically easier in paramedian as compared to the median approach in T7-9 thoracic region with no difference in complications.

Evaluation of respiratory exchange ratio (RER) for predicting postoperative outcomes in elderly patients undergoing oncological resection for gastrointestinal malignancies - A prospective cohort study.

Background and Aims: Predicting complications after major oncosurgery is particularly daunting in the elderly subcategory of patients owing to factors like preexisting age-related immune cellular senescence and a significant imbalance of oxygen delivery (DO2) and consumption (VO2) characteristic of major oncological surgeries. The respiratory exchange ratio (RER) indicates DO2-VO2 balance and onset of anaerobic metabolism. We evaluated the ability of RER in predicting the occurrence of postoperative complications following geriatric oncosurgery. Materials and Methods: In the study, we enrolled 96 patients aged 65 years and above undergoing definitive surgery for gastrointestinal malignancy. The RER was calculated at predefined time points by a non-volumetric method from the respiratory parameters as RER = (end-tidal fractional carbon dioxide [FetCO2] - fraction of inspired carbon dioxide [FiCO2]/fraction of inspired oxygen [FiO2] - end-tidal fractional oxygen [FetO2]). Other indices of tissue perfusion, like central venous oxygen saturation and lactate levels, were also recorded. The patients were followed up for postsurgical complications. The predictive value of RER and other perfusion parameters was assessed and compared by appropriate statistical methods. Results: The patients who sustained major complications had a higher RER than the patients who did not sustain complications (1.47 ± 0.99 vs. 0.90 ± 0.31, P = 0.001). An intraoperative cutoff value of RER ≥0.89 was found to best predict postoperative complications at a specificity and sensitivity rate of 81.2% and 76%, respectively. End-operative partial pressure of carbon dioxide (pCO2) gap of >5.2 mm and elevated arterial lactate could also predict postsurgical complications in this age group. Conclusion: The RER can serve as a noninvasive, real-time and sensitive indicator of tissue hypoperfusion and postoperative complications in geriatric gastrointestinal oncosurgery.

Comparison of Intubation Conditions Between Airtraq, McGrath Video Laryngoscopes, and Macintosh Under Conditions of Simulated Trauma Airway and Rapid Sequence Induction Intubation.

BACKGROUND: Patients arriving at the emergency department with a potential cervical spine injury and immobilized in a rigid cervical collar often require emergency airway management and rapid sequence induction intubation (RSII). There have been several advances in airway management with the advent of channeled (AirtraqⓇ; Prodol Meditec) and nonchanneled (McGrathⓇ; Meditronics) video laryngoscopes, which enable intubation without the removal of the cervical collar, but their efficacy and superiority over conventional laryngoscopy (Macintosh) in the presence of a rigid cervical collar and cricoid pressure have not been evaluated. OBJECTIVE: Our aim was to compare the channeled (Airtraq [group A]) and nonchanneled (McGrath [Group M]) video laryngoscopes with a conventional laryngoscope (Macintosh [Group C]) in a simulated trauma airway. METHODS: A prospective randomized controlled study was conducted in a tertiary care center. Participants were 300 patients requiring general anesthesia (American Society of Anesthesiologists class I or II), of both sexes, and aged 18-60 years. Airway management was simulated without removal of a rigid cervical collar and using cricoid pressure during intubation. After RSI, patients were intubated with one of the study techniques according to randomization. Intubation time and intubation difficulty scale (IDS) score were noted. RESULTS: Mean intubation time was 42.2 s in group C, 35.7 s in group M, and 21.8 s in group A (p = 0.001). Intubation was easy in group M and group A (median IDS score of 0; interquartile range [IQR] 0-1 for group M and median IDS score of 1; IQR 0-2 for group A and group C; p < 0.001). A higher proportion (95.1%) of patients had an IDS score of < 1 in group A. CONCLUSIONS: The performance of RSII with cricoid pressure in the presence of a cervical collar was easier and more rapid with channeled video laryngoscope than with other techniques.

Comparison of fentanyl and nalbuphine as adjuvants to intrathecal 0.5% bupivacaine in lower limb surgeries: A randomised double-blind prospective study.

INTRODUCTION: Local anaesthetics used in spinal anaesthesia have a limited duration of action. To prolong postoperative analgesia, adjuvants, mainly opioids, are used. As µ agonist drugs have side effects, other receptor agonists are considered. Nalbuphine is a safe and effective kappa agonist adjuvant. AIM: To compare the analgesic efficacy between fentanyl and nalbuphine adjuvants added to 3 mL of 0.5% intrathecal hyperbaric bupivacaine. MATERIALS AND METHODS: This prospective, double-blind, comparative study was conducted in 60 patients of either sex belonging to the American Society of Anesthesiologists classes I and II aged 18-65 years undergoing lower limb surgery with entropy monitoring, randomly allocated into two groups. Group F (n = 30) received 0.5% hyperbaric bupivacaine (3 mL) + 25 µg (0.5 mL) fentanyl. Group N (n = 30) received 0.5% hyperbaric bupivacaine (3 ml) + 0.8 mg (0.5 mL) nalbuphine intrathecally. Hemodynamics, entropy, motor and sensory block characteristics, and complications were noted. RESULTS: The nalbuphine group had a significantly longer two-segment regression time of sensory blockade and extended analgesia duration than the fentanyl group. Haemodynamics, entropy, time for onset of sensory and motor blockade and adverse effects were comparable in both groups. CONCLUSION: Nalbuphine prolongs sensory blockade and postoperative analgesia duration with minimal side effects and is a safe intrathecal adjuvant.

Effect of stress on contextual pain sensitivity in the preoperative period- A proof of concept study.

Background and Aims: The importance of non-noxious contextual inputs in the interplay of pain with neurophysiologic and behavioral factors is gaining recognition. Stress of impending surgery can act as a negative context, leading to a decrease in pain threshold in patients. This study was conducted to assess the influence of stress conferred by the imminent and other contextual inputs such as anxiety, socioeconomic status, prior painful experience, and the effect of gender on modulation of pain perception in patients undergoing elective surgery. Material and Methods: In total, 120 patients aged between 18 and 60 years of either gender posted for elective gastrointestinal surgery under general anesthesia were recruited. Data were collected on preoperative anxiety level, socioeconomic status, education, and any prior painful experience. A pressure algometer was used to measure the pressure pain thresholds and pain tolerance on the day before surgery and on the morning of surgery in the preoperative suite. Results: There was a statistically significant decrease in both pain threshold (P < 0.0001) and pain tolerance in the immediate preoperative period in comparison to the baseline readings taken the day before surgery (P = 0.048). The magnitude of change in pain scalars was greater in females (P < 0.001), those with a high anxiety score, and a history of severe painful experience in the past. Conclusion: Preoperative surgical stress lowers the pain threshold and pain tolerance. Contextual modulation of pain by factors such as anxiety and memory of prior painful experience, especially in the female gender, could influence postoperative patient outcomes and warrants further research.

Dynamometer based hand grip strength as a clinical tool for objective assessment of post-operative residual muscle weakness.

Background and Aims: Residual neuromuscular block continues to be a significant postoperative complication despite neuromuscular monitoring. This study aims to determine the applicability of a hand-held forced dynamometer for hand grip strength assessment as an objective measure of residual muscle weakness. Methods: The study included patients undergoing surgery under general anaesthesia. A demonstration was given to the patient on the usage of a dynamometer for handgrip strength and a peak expiratory flow meter for peak expiratory flow rate (PEFR) and baseline values were recorded. The parameters were monitored at 15 minutes post-extubation and again at intervals of 15 minutes until one hour, half-hourly until four hours, and hourly until six hours post-operatively. Paired t-test was used for comparison of baseline muscle strength and PEFR with the parameters at different time points. Association between muscle strength and PEFR was tested with the Pearson-correlation test. Results: Muscle strength was 50 to 60%, 75% and 100% of baseline at 15, 45 and 210 minutes after extubation, respectively. PEFR was 50 to 60%, 75% and 100% of baseline at 15, 60 and 180 minutes after extubation. The Pearson-correlation test established a positive correlation between handgrip strength and PEFR (correlation-coefficient 0.86). Conclusion: A significant reduction in the postoperative muscle strength can be detected using an objective forced dynamometer to measure handgrip strength even when train of four count has returned to unity and even when there are no clinical signs of muscle weakness. The residual muscle weakness is significant enough to affect the PEFR in the postoperative period.

Comparison of Airtraq DL™ and Macintosh laryngoscope for double-lumen tube placement in simulated difficult airway: A randomised study.

Background and Aims: The Airtraq DL ™ is a prototype channeled video laryngoscope, designed specifically for endobronchial intubation with a double-lumen tube (DLT). Evidence on its superiority over Macintosh laryngoscope for DLT placement in the difficult airway is limited. This study compared the efficacy of both these laryngoscopes in the simulated difficult airway. Methods: A prospective randomised controlled study was conducted on 52 patients undergoing elective thoracic surgery with lung isolation using a left-sided DLT. The patients were randomised into Airtraq DL ™ group (group A) and Macintosh group (group M). The primary objective was to compare the time required for intubation, and the secondary objectives were to evaluate time to best glottic view, Cormack-Lehane (CL) grading, intubation difficulty score (IDS), manoeuvres, attempts at intubation, haemodynamic response and complications. Operating anaesthesiologists were also asked to grade the ease of laryngoscopy and intubation for both devices on a 4-point Likert scale. Results: The mean time to intubation was found to be lesser in group A than in group M (18 ± 6.91 s vs 25.48 ± 9.47 s, P = 0.003). Group A showed better CL grading (P ≤ 0.001), lesser requirement of manoeuvres (P = 0.02) and lower IDS (P = 0.003). Also, group A had significantly better Likert scale results as compared to group M. Conclusion: The Airtraq DL ™ is superior to Macintosh laryngoscope as it requires lesser time for intubation and provides favourable intubating conditions (better CL grading, lesser manoeuvres, lower IDS and improved Likert scales) for double-lumen placement in the simulated difficult airway.

Myasthenia Gravis: An Unanticipated Cause of Failure to Wean in a Postpartum Patient with Preexisting Systemic Lupus Erythematosus.

Sudden onset and de novo Myasthenia gravis (MG) in the presence of systemic lupus erythematosus (SLE) is a rare postpartum phenomenon and can easily misguide the treating physician. A known case of SLE, 4 days after an elective cesarean section, presented to the intensive care unit for weaning-off mechanical ventilation after being put on ventilatory support in the emergency room, following acute-onset partial seizures. She was subsequently diagnosed to have new-onset MG, treated for the condition and later successfully extubated. How to cite this article: Patki AY, Durga P, Gangishetty A, Ketireddy T, Noorain N. Myasthenia Gravis: An Unanticipated Cause of Failure to Wean in a Postpartum Patient with Preexisting Systemic Lupus Erythematosus. Indian J Crit Care Med 2022;26(6):731-732.

Effect of pregabalin on postoperative pain and instrumentation-induced dysuria in patients undergoing percutaneous nephrolithotomy: A prospective randomized, double-blinded placebo-controlled study.

Background and Aims: The manipulation of urinary tract, the mandatory requirement of ureteral stenting, and bladder catheterization in patients undergoing percutaneous nephrolithotomy (PCNL) produces significant pain and dysuria postoperatively. The present study compared the efficacy of pregabalin with placebo in attenuation of these symptoms in patients undergoing PCNL. Material and Methods: This randomized controlled study was conducted in 110 patients of either sex, aged 18-65 years undergoing elective PCNL requiring nephrostomy tube under general anesthesia. Group G (n: 53) received pregabalin 150 mg and Group P received placebo (n: 49) orally 1 h before the anesthetic induction. All the patients received standard anesthetic protocol. Pain at the site of nephrostomy, instrumentation-induced dysuria (IID), anxiety, and sedation scores were recorded at 0 min, 15 min, 30 min, 1 h, 2 h, 4 h, 8 h, 12 h, 24 h postoperatively. Hemodynamics, total requirement of rescue analgesia, and incidence of any adverse effects were also noted. Results: Patients were demographically comparable between the two groups. There is no difference in nephrostomy site pain between the groups at different points of measurements. IID was less with pregabalin at 0 min, 15 min, 30 min, 1 h, and 2 h after extubation (P value < 0.05, 43% in Group G vs. 68% in group P). Severe urgency was seen in 4%, moderate in 31%, and mild in 33% of patients in placebo group. No patient in pregabalin had severe grade of instrumentation-induced dysuria score (P < 0.05). Patients in Group P required more rescue analgesic (P: 0.009). Anxiety scores, sedation scores, and hemodynamic parameters were comparable. Conclusion: A single dose of 150 mg pregabalin as oral premedication given 1 h before surgery reduced the incidence and intensity of IID compared to placebo in patients undergoing PCNL without significant adverse effects.

Comparison of efficacy of gabapentin and memantine premedication in laparoscopic cholecystectomies for postoperative pain relief - A randomised placebo controlled trial.

BACKGROUND AND AIMS: The multiplicity of the mechanisms of the pain in laparoscopic cholecystectomy inclines us to the usage of multimodal analgesia. Gabapentin is known for its analgesic efficacy when given as premedication in many surgeries. N-methyl-D-aspartate (NMDA) antagonists are used for both acute and chronic pain, but the use of memantine in the perioperative period is less studied. The aim of this randomised controlled study was to subjectively and objectively compare postoperative pain relief using gabapentin, memantine and placebo as premedication. METHODS: Sixty-six patients posted for laparoscopic cholecystectomy were randomised into three groups. During the preoperative assessment, the baseline threshold and tolerance values of pain were measured using an algesiometer. Patients were pre-medicated with oral gabapentin 600 mg or memantine 20 mg or placebo an hour before surgery. Following extubation, pain scores were reassessed (both subjectively and objectively) along with Ramsay sedation scores at different time intervals for 4 h postoperatively. RESULTS: Gabapentin group had lower Numerical Rating Scale scores at 15 min and 1 h postoperatively when compared to the other two groups. Memantine group had a longer time for the first request for rescue analgesia (50.53 min) compared to gabapentin and placebo. The objective assessment of pain with analgesiometer showed no statistical significance between the three groups for both threshold and tolerance values. Ramsay sedation scores were higher in the gabapentin group compared to the other two. CONCLUSION: Gabapentin provides better postoperative pain relief compared to memantine when given as single dose premedication for laparoscopic cholecystectomy.

Choosing Neuroanaesthesia as a career: Marching towards new horizons.

Anaesthesiology is an ever-changing science and amongst its sub-specialities, the field of neuroanaesthesia is making rapid strides. The fragility of the brain and spinal cord and the multitude of complexities involved in neurosurgery and interventional neuroradiological procedures demand dedicated training in neuroanaesthesia. With rapid advancement in other neuroscience specialties, neuroanaesthesia too has made outstanding progress, owing to establishment of structured training, publication of high-quality scientific research, and invention of novel medications and monitoring modalities. The opportunities for training in India and abroad and resources to broaden knowledge in neuroanaesthesia have increased over the last two decades. A career in neuroanaesthesia offers a great future for budding anaesthesiologists.

Administration of Intravenous Amino Acids Attenuates Postoperative Hypothermia in Patients Undergoing Percutaneous Nephrolithotomy.

OBJECTIVE: Amino acids attenuate hypothermia during the perioperative period by increasing thermogenesis and stimulating energy consumption. Percutaneous nephrolithotomy (PCNL) induces profound hypothermia owing to the use of large volumes of irrigating fluids. The role of amino acids in this group of surgeries for hypothermia and shivering prevention has been evaluated in this study because there is no available literature of concern. METHODS: This prospective randomised controlled trial was conducted in patients undergoing PCNL. Group A received amino acids at 60 mL h-1 an hour before surgery until the end of surgery. Group C received normal saline infusion. Perioperative nasopharyngeal temperature, haemodynamics, and postoperative shivering were recorded. RESULTS: Although there was no significant difference in temperature in the intraoperative period, postoperative decrease in the temperature was less in the amino acid group. In the postoperative period, 2 patients in the amino acid group and 11 patients in the control group experienced shivering. CONCLUSION: Intravenous administration of amino acids attenuated postoperative hypothermia and reduced shivering in patients undergoing PCNL without any adverse effects.

Comparison of sensory posterior articular nerves of the knee (SPANK) block versus infiltration between the popliteal artery and the capsule of the knee (IPACK) block when added to adductor canal block for pain control and knee rehabilitation after total knee arthroplasty---A prospective randomised trial.

BACKGROUND AND AIMS: Adductor canal block (ACB), though an effective procedure for postoperative analgesia in total knee arthroplasty (TKA), does not provide analgesia to the posterior articular aspect of the knee joint. Infiltration between the popliteal artery and the capsule of the knee (IPACK block) and sensory posterior articular nerves of the knee (SPANK block) are two single injection techniques that have been shown to provide effective analgesia in posterior knee pain. This study aims to compare the effect of IPACK block and SPANK block when combined with ACB for analgesia and postoperative rehabilitation in TKA. METHODS: A total of 82 patients were randomised into two groups: (1) ACB combined with IPACK, (2) ACB combined with SPANK block. The primary outcome was the pain scores from 6 h to 48 h after surgery and the duration of postoperative analgesia. The secondary outcome measures were 24 h opioid consumption, ambulation parameters like mobilisation ability, quadriceps muscle strength and patient satisfaction score at discharge. RESULTS: Numerical rating scale (NRS) scores at rest and on movement, duration of analgesia, total opioid consumption, and patient satisfaction were significantly better (P < 0.05%) in the IPACK group than in the SPANK block. There were no significant differences in the knee rehabilitation parameters between the blocks. CONCLUSION: ACB with IPACK block offers better analgesia, less opioid consumption and better patient satisfaction with comparable knee rehabilitation parameters in the immediate postoperative period after TKA compared to ACB with SPANK block.

Comparison of Postoperative Pain and Analgesia Requirement among Diabetic and Nondiabetic Patients undergoing Lower Limb Fracture Surgery - A Prospective Observational Study.

Background: Diabetic patients usually experience neuropathic pain and have a decreased response to opioids. Fractures are acute conditions and as such, they are very painful. No data is available related to fracture and postoperative pain in diabetics. Aim: This study was conducted to evaluate postoperative pain and analgesics requirement among diabetic and nondiabetic patients undergoing lower limb fracture surgery and the effect of glycosylated hemoglobin (HbA1c) on the postoperative pain. Setting and Design: This was a prospective observational study, conducted on 80 patients comprising of nondiabetic and diabetic, scheduled for elective lower limb fracture surgery under spinal anesthesia. Materials and Methods: HbA1c was done in all the patients who were included in the study. Postoperative Visual Analog Scale (VAS) and analgesic consumption were assessed by an anesthesiologist blinded to the diabetic or nondiabetic status of the patients. VAS was assessed every 2nd hourly, for 24 h and rescue analgesia was given if the VAS was ≥4 and record was maintained. Sedation scores and adverse effects were also recorded postoperatively. Statistical Analysis: The Chi-square test was used for the analysis of categorical variables and Student's t-test was used for continuous variables. Results: Diabetic group of patients had a significantly high VAS score with P ≤ 0.05. Rescue analgesics requirement was significantly different in two groups with diabetic patients requiring more supplementation of analgesia with a P = 0.025. The overall patient satisfaction was lesser in diabetic group (P = 0.004). There was statistically significant correlation between glycosylated hemoglobin and VAS at 2nd, 16th, 18th, 20th, 22nd, and 24th h. Conclusion: Postoperative pain and analgesic requirement was significantly higher in diabetic patients with lower limb fracture. Glycosylated hemoglobin had good correlation with higher VAS.

A negative preoperative 99mTechnetium tetrofosmin myocardial perfusion imaging scan with postoperative acute coronary syndrome - A case of balanced ischaemia.

Perioperative myocardial infarction (PMI) is an important indicator of outcome after noncardiac surgery. Identifying patients at risk of PMI helps in risk stratification and modification. Myocardial perfusion imaging (MPI) is an established diagnostic modality for detection and prognostication of coronary artery disease (CAD). We report a case wherein preoperative MPI was negative for CAD but patient presented with acute coronary event in the postoperative period. We identify and evaluate the reasons for the failure of MPI in detection of CAD in our patient.