Endotracheal intubation is a critical procedure in managing patients with head injuries, ensuring airway protection and facilitating mechanical ventilation. However, the process of laryngoscopy and intubation can provoke significant hemodynamic responses, including elevations in heart rate (HR) and mean arterial pressure (MAP), which may exacerbate intracranial pressure (ICP) and compromise cerebral perfusion. Such hemodynamic fluctuations pose substantial risks in head-injured patients, where maintaining stable ICP and cerebral perfusion is paramount. 

To mitigate these adverse responses, various pharmacological agents have been employed. Lignocaine, a local anesthetic, is commonly administered either intravenously or intratracheally to suppress airway reflexes and blunt hemodynamic reactions during intubation. Its efficacy in attenuating increases in HR and MAP during extubation has been documented, contributing to smoother emergence from anesthesia.

Dexmedetomidine, an α₂-adrenergic agonist, has gained attention for its sedative, analgesic, and sympatholytic properties. By reducing sympathetic outflow, it helps maintain hemodynamic stability during stressful procedures. Studies have indicated that dexmedetomidine effectively attenuates the hemodynamic responses associated with airway manipulation, including during extubation, by decreasing HR and MAP.

While the individual effects of lignocaine and dexmedetomidine on hemodynamic responses during airway management have been explored, there is limited research on the combined use of intratracheal dexmedetomidine and lignocaine prior to intubation, particularly in head injury patients. This study aims to evaluate the efficacy of intratracheal administration of dexmedetomidine combined with 4% lignocaine in attenuating hemodynamic changes during intubation in patients with head injuries. By assessing parameters such as HR, MAP, and ICP before and after intubation, the study seeks to determine whether this combination offers superior hemodynamic stability compared to standard practices, thereby potentially improving outcomes in this vulnerable patient population.

Study Design: A prospective, randomized, double-blind, placebo-controlled trial.

Ethical Approval: The study was approved by the Institutional Ethics Committee, and written informed consent was obtained from the legal guardians of all participants.

Study Population: 60 head injury patients requiring intubation were enrolled.

Inclusion Criteria:

• Age 18–65 years
• Glasgow Coma Scale (GCS) score ≤ 8
• Hemodynamically stable (SBP > 90 mmHg, HR > 60 bpm)
• Requiring endotracheal intubation for airway management
•  

Exclusion Criteria:

• Known allergy to dexmedetomidine or lignocaine
• Severe cardiovascular or respiratory disease
• Pregnancy or lactation
• Hemodynamic instability (SBP < 90 mmHg, HR < 60 bpm)
• Patients on beta-blockers or calcium channel blockers

Randomization and Blinding: Patients were randomized into two groups using a computer-generated random number table. Group A (n=30) received intratracheal dexmedetomidine (1 µg/kg) + 4% lignocaine (2 mg/kg), and Group B (n=30) received intratracheal normal saline (placebo). The study drugs were prepared by an independent anesthesiologist not involved in the study, ensuring blinding of the investigators and patients.

Intervention:

• After standard monitoring (ECG, SpO₂, NIBP), patients were preoxygenated with 100% oxygen for 3 minutes.
• The study drug was administered intratracheally via a mucosal atomization device.
• Intubation was performed 3 minutes after drug administration using a standard technique.

Outcome Measures:

• Primary: Hemodynamic parameters (HR, SBP, DBP, MAP, RPP) recorded at baseline (T0), during intubation (T1), and at 1 (T2), 3 (T3), 5 (T4), and 10 (T5) minutes post-intubation.
• Secondary: Incidence of adverse events (bradycardia, hypotension, airway irritation).

Statistical Analysis: Data were analyzed using SPSS version 25.0. Continuous variables were expressed as mean ± SD and compared using Student’s t-test. Categorical variables were expressed as percentages and compared using the Chi-square test. A p-value < 0.05 was considered statistically significant.

Table 1: Baseline Characteristics of Patients

Table 2: Comparison of Heart Rate (HR) Between Groups

Table 3: Comparison of Systolic Blood Pressure (SBP) Between Groups

Table 4: Comparison of Mean Arterial Pressure (MAP) Between Groups

Table 5: Comparison of Rate-Pressure Product (RPP) Between Groups

The study demonstrates that intratracheal dexmedetomidine combined with 4% lignocaine effectively attenuates the hemodynamic response to intubation in head injury patients. The sympatholytic properties of dexmedetomidine, combined with the local anesthetic effect of lignocaine, provide a synergistic effect in stabilizing HR and BP.¹¹¹² This is particularly beneficial in head injury patients, where hemodynamic instability can lead to increased ICP and secondary brain injury. ¹³

The findings are consistent with previous studies showing that dexmedetomidine reduces sympathetic outflow and attenuates the stress response to intubation. ¹⁴¹⁵ The addition of lignocaine further suppresses airway reflexes, contributing to smoother intubation conditions. ¹⁶ However, caution is warranted to avoid excessive bradycardia or hypotension, which could compromise cerebral perfusion.¹⁷

The study highlights the potential of this combination as a safe and effective strategy for managing hemodynamic changes during intubation in head injury patients. Further research is needed to explore long-term outcomes and optimal dosing regimens.

Intratracheal dexmedetomidine combined with 4% lignocaine significantly attenuates hemodynamic changes during intubation in head injury patients, reducing the risk of secondary brain injury. This combination offers a promising approach to improving outcomes in this vulnerable population.

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