Daily Anesthesiology Research Analysis
Top advances span ICU neuroprognostication, perioperative pulmonary risk reduction, and intubation hemodynamic control. Quantitative EEG during sedation interruption improved outcome prediction after severe brain injury, a multicenter cohort identified modifiable factors for postoperative pulmonary complications in emergency abdominal surgery, and a randomized trial found transtracheal lignocaine stabilizes intubation hemodynamics better than intravenous dosing.
Summary
Top advances span ICU neuroprognostication, perioperative pulmonary risk reduction, and intubation hemodynamic control. Quantitative EEG during sedation interruption improved outcome prediction after severe brain injury, a multicenter cohort identified modifiable factors for postoperative pulmonary complications in emergency abdominal surgery, and a randomized trial found transtracheal lignocaine stabilizes intubation hemodynamics better than intravenous dosing.
Research Themes
- ICU neuroprognostication and quantitative EEG
- Perioperative pulmonary complications and modifiable risk factors
- Airway management and hemodynamic attenuation during intubation
Selected Articles
1. EEG Response to Sedation Interruption Complements Behavioral Assessment After Severe Brain Injury.
In 41 severely brain-injured patients undergoing propofol sedation interruption, quantitative EEG features (power, spatial ratios, spectral exponent) reflected recovery and sometimes revealed neurophysiologic signs of awakening despite absent behavior. Combining EEG with behavioral assessment improved prediction of survival and recovery and outperformed attending physicians’ outcome predictions.
Impact: Introduces an objective neurophysiologic adjunct to the neurological wake-up test that improves prognostication after severe brain injury. This addresses a known gap where behavior alone is often ambiguous under sedation.
Clinical Implications: Quantitative EEG during sedation interruption can be integrated into ICU protocols to complement behavioral assessments, support family counseling, and guide goals-of-care discussions, potentially reducing premature withdrawal or overtreatment.
Key Findings
- EEG power, spatial ratios, and spectral exponent tracked recovery during propofol sedation interruption.
- Neurophysiologic signs of awakening were detectable even when behavioral responses were absent.
- Adding EEG to behavioral assessment improved prognostic discrimination for survival and recovery and outperformed attending physician predictions.
Methodological Strengths
- Prospective acquisition of high-density (128-channel) EEG during a standardized clinical test
- Use of quantitative EEG metrics and comparison against clinician prognostication
Limitations
- Modest single-center sample size (n=41) limits generalizability
- Findings specific to propofol sedation interruption; thresholds and workflows need external validation
Future Directions: Multicenter validation of EEG thresholds and integration into wake-up test protocols; development of automated algorithms to support bedside prognostication and decision-making.
OBJECTIVE: Accurate assessment of the level of consciousness and potential to recover in patients with severe brain injury underpins crucial decisions in the intensive care unit but remains a major challenge for the clinical team. The neurological wake-up test is a widely used assessment tool. However, many patients' behavioral responses during a short interruption of sedation are ambiguous or absent, yielding little prognostic value. This study assesses the brain's electroencephalogram response during an interruption of propofol sedation to complement behavioral assessment during the neurological wake-up test to predict survival, recovery of consciousness, and long-term functional outcomes in patients with acute severe brain injury. METHODS: We recorded 128-channel EEG from 41 severely brain-injured patients during a clinically indicated neurological wake-up test. Behavioral assessment was performed before and after interruption of propofol sedation, using the Glasgow Coma Scale. Brain response to sedation interruption was quantified using EEG power, spatial ratios, and the spectral exponent. RESULTS: Recovery of responsiveness during the neurological wake-up test is reflected in participants' brain response to sedation interruption. Electrophysiological patterns can be decoupled from participant behavioral response, with some individuals demonstrating neurophysiological signs of waking up despite an absent behavioral response. Using the brain response to complement behavioral assessment improved prognostic value, distinguished patients according to survival and outperformed outcome predictions of the patients' attending physician. INTERPRETATION: EEG can complement behavioral assessment during the neurological wake-up test to improve prognostication, inform clinicians, family members, and caregivers, and to set realistic goals for treatment and therapy.
2. Postoperative pulmonary complications in emergency abdominal surgery. A prospective international cohort study.
In 507 adults undergoing emergency abdominal surgery, postoperative pulmonary complications occurred in 22.5% and severe PPCs in 7.5% within 7 days. High ARISCAT score, laparotomy, and a positive postoperative air-test were independent risk factors, whereas neuromuscular block reversal was associated with reduced PPC risk.
Impact: Defines PPC burden and identifies modifiable perioperative factors in a vulnerable, understudied setting, offering immediate targets for quality improvement.
Clinical Implications: Routinely use neuromuscular blockade reversal, minimize laparotomy when feasible, and leverage postoperative air-leak tests to risk-stratify for intensified respiratory care.
Key Findings
- PPC incidence within 7 days was 22.5% (severe PPCs 7.5%) after emergency abdominal surgery.
- Independent risk factors: high ARISCAT score (OR 2.67), laparotomy (OR 2.29), positive postoperative air-test (OR 2.05).
- Neuromuscular block reversal was associated with a lower risk of PPCs (OR 0.36).
Methodological Strengths
- Prospective international cohort with standardized PPC definitions
- Multivariable modeling identifying independent and modifiable risk factors
Limitations
- Observational design limits causal inference
- Site-level 7-day recruitment windows may introduce selection bias and heterogeneity
Future Directions: Interventional studies testing standardized reversal protocols and postoperative respiratory bundles in emergency surgery; external validation across broader regions.
BACKGROUND: Emergency abdominal surgery is a high-risk procedure often performed on high-risk patients. The incidence of Postoperative pulmonary complications (PPCs) in emergency abdominal surgery is not well established yet. Several factors, such as the ventilatory approach, may be associated with PPCs but data on patients undergoing emergency abdominal surgery is scarce. The primary aim of the study was to describe the incidence of PPCs during the first 7 postoperative days. METHODS: Prospective international cohort study including all consecutive patients > 18 y/o undergoing emergency abdominal surgery. From April to June 2023 each hospital selected a single 7-day period for the recruitment with a 7-day follow-up. The PPCs included the following international standard definitions for the primary outcome: acute respiratory failure; pneumothorax; weaning failure; acute respiratory distress syndrome; pulmonary infection; atelectasis; pleural effusion; bronchospasm; aspiration pneumonitis; pulmonary thromboembolism; and pulmonary edema. RESULTS: 45 hospitals from 5 geographical areas participated in the study with 507 patients included in the final analysis. A total of 114 (22.5%) patients developed PPCs and 38 (7.5%) developed severe PPCs. The multivariate analysis showed that the independent risk factors for PPCs were: high ARISCAT score (Odds Ratio: 2.67; 95%CI 1.06-6.86), laparotomy (OR: 2.29; 95%CI 1.06-5.01), and postoperative positive air-test (OR: 2.05; 95%CI 1.02-4.24). Conversely, neuromuscular block reversal was associated with a reduced risk of PPCs (OR: 0.36; 95%CI 0.16-0.82). CONCLUSION: Incidence of PPCs in patients undergoing emergency abdominal surgery is significant. Among the modifiable risk factors, a lack of neuromuscular block reversal and postoperative positive air test were associated with the increased incidence of PPCs.
3. Comparison between transtracheal and intravenous 2% lignocaine in attenuating hemodynamic stress response following direct laryngoscopy and endotracheal intubation: a randomized controlled trial.
In a randomized trial of 138 patients, transtracheal 2% lignocaine (1.5 mg/kg) resulted in less post-induction hypotension and a smaller 3-minute post-intubation surge in mean blood pressure and heart rate than intravenous lignocaine at the same dose.
Impact: Provides practical, immediately actionable evidence that transtracheal lignocaine improves hemodynamic stability around intubation compared with standard intravenous administration.
Clinical Implications: Consider transtracheal lignocaine (1.5 mg/kg) after induction to blunt intubation responses, especially in patients at risk from hemodynamic surges (e.g., coronary disease, intracranial pathology).
Key Findings
- Transtracheal lignocaine led to less post-induction hypotension than intravenous lignocaine (median MBP 71 vs 68 mmHg; P=0.018).
- At 3 minutes post-intubation, smaller surges in mean blood pressure and heart rate were observed with transtracheal administration (MBP P=0.009; HR P=0.015).
- Trial registered (CTRI/2023/06/054125), supporting methodological transparency.
Methodological Strengths
- Randomized allocation with prespecified hemodynamic timepoints
- Clinically relevant outcomes with statistically significant differences
Limitations
- Likely single-center, with unclear blinding which may introduce performance bias
- Short-term outcomes; no long-term adverse event assessment reported
Future Directions: Confirm benefits in high-risk populations and compare with other adjuncts (e.g., opioids, beta-blockers); assess patient-centered outcomes and safety across diverse settings.
BACKGROUND AND AIMS: Lignocaine is used through various routes to mitigate the hemodynamic surge associated with laryngoscopy and endotracheal intubation during general anesthesia. This study hypothesized that post-induction administration of transtracheal 2% lignocaine at 1.5 mg/kg would have a similar effect to intravenous 2% lignocaine at the same dosage, providing an alternative for attenuating the hemodynamic stress response. METHODS: A total of 138 consenting patients were randomized into two groups. Following induction, Group IV patients received 2% lignocaine at 1.5 mg/kg intravenously, while Group TT patients received 2% lignocaine at 1.5 mg/kg transtracheally. The primary outcome was the comparison of hemodynamic responses at different time points around intubation. The secondary outcome was the incidence of sore throat. Data analyses were done using the Statistical Software Jupyter Notebook, running in a Python 3.11 environment. RESULTS: Post-induction hypotension was significantly less pronounced in the TT group [Mean blood pressure (median with IQR) IV group 68(60-78) mm of Hg vs. TT group 71(66-82.25) mm of Hg, P = 0.018]. TT group patients experienced a significantly smaller post-intubation surge at 3 minutes in blood pressure and heart rate compared to the IV group [Mean blood pressure (median with IQR) IV group 79(71-87) mm of Hg vs. TT group 73(65-81) mm of Hg, P = 0.009 and Heart rate (median with IQR) IV group 80(70-94) per minute vs. 71.5(64-82.75) per minute P = 0.015]. CONCLUSION: Transtracheal lignocaine is more likely to maintain stable hemodynamics during intubation compared to intravenous lignocaine. TRIAL REGISTRATION: CTRI/2023/06/054125 [Registered on: 19/06/2023]. This trial is registered with the Clinical Trial Registry of India https://ctri.nic.in/Clinicaltrials/login.php .