Low Dose Dexmedetomidine Attenuates Hemodynamic Response to Skull Pin Holder Application

A Comparative Study of Intravenous Dexmedetomidine with Local Infiltration of Ropivacaine in Attenuation of Stress Response to Skull Pin Insertion in Craniotomies

Objective  Skull pin insertion in patients undergoing craniotomies elicits hemodynamic and neuroendocrine stress response that may be deleterious to the patient. Various drugs and techniques have been documented in literature to abate this stress response. Against this background, we aimed to compare the efficacy of intravenous dexmedetomidine and local infiltration of ropivacaine for attenuation of stress response to pin insertion in craniotomies.

Methods  Eighty-eight adult patients undergoing craniotomy under general anesthesia from March 2019 to April 2020 requiring application of head holder were randomized into two equal groups. After intubation, 0.75 µg kg ⁻¹ of dexmedetomidine over 10 minutes through infusion was given in group D, while local infiltration at pin sites was done with 0.5% ropivacaine, 2 mL at each site in group R. Hemodynamic parameters and levels of serum cortisol, prolactin, and blood glucose were measured before and after pin insertion. Unpaired t -test for continuous variables and Mann–Whitney U test was used for nonnormally distributed variables.

Results  Heart rate was statistically similar between the two groups at all the observed time points. The difference in mean arterial pressure values between the two groups was found to be statistically significant only from 10 to 20 minutes after pin insertion being statistically similar at rest of the time points. Levels of serum glucose, cortisol, and prolactin values 30 minutes after pin insertion were statistically similar between both groups.

Conclusion  We concluded that both interventions are equally efficacious in attenuation of hemodynamic and stress response to head holder application in patients undergoing craniotomies.

Comparison of effects of dexmedetomidine added to ropivacaine versus ropivacaine alone infiltration scalp block for attenuation of the haemodynamic response to skull pin placement in neurosurgical procedures: A double-blind, randomised clinical trial

BACKGROUND AND AIMS

Skull pin head holder application is intensely painful and is accompanied with abrupt increase in heart rate and arterial blood pressure. We aimed to determine the effects of adding dexmedetomidine to ropivacaine scalp block in attenuating the haemodynamic response to skull pin insertion in neurosurgical procedures.

METHODS

Sixty patients were randomly allocated to receive scalp block with 25 ml of 0.5% ropivacaine added with either normal saline (control group) or dexmedetomidine (1 μg/kg) after anesthesia induction. A standard uniform general endotracheal anaesthesia protocol was followed in all study subjects. Heart rate and blood pressure measurements were made at baseline, 1, 3, 5, 10, and 15 min following skull pin placement. Student's independent t-test, Chi-square test and repeated measure analysis of variance were used to analyse the obtained data.

RESULTS

There was no significant attenuation of heart rate (P = 0.418), systolic (P = 0.542), diastolic (P = 0.793) and mean blood pressure (P = 0.478) with addition of dexmedetomidine to ropivacaine.

CONCLUSIONS

The addition of dexmedetomidine (1 μg/kg) to 25 ml of 0.5% ropivacaine offers no additional benefit over 25 ml of 0.5% ropivacaine alone scalp block in attenuating the haemodynamic response to skull pin placement in neurosurgical procedures.

Analgesia nociception index and hemodynamic changes during skull pin application for supratentorial craniotomies in patients receiving scalp block versus pin-site infiltration: A randomized controlled trial

Background:

Noxious stimulation such as skull pin insertion for craniotomy elicits a significant hemodynamic response. Both regional analgesic techniques (pin-site infiltration [PSI] and scalp block [SB]), and systemic strategies (opioids, alpha-2 agonists, anesthetics, and beta-blockers) have shown to attenuate this response. Analgesia Nociception Index (ANI) provides objective information about the magnitude of nociception and adequacy of analgesia. This study compared ANI and hemodynamic changes in patients receiving local anesthetic SB versus PSI during skull pin application for craniotomy.

Materials and Methods:

Sixty adult patients scheduled for elective supratentorial tumor surgery were randomly allocated to receive local anesthetic SB or PSI for skull pin insertion after the induction of anesthesia. Data regarding heart rate (HR), blood pressure (BP), and ANI were collected every minute for 5 min after the skull pin insertion beginning from the baseline.

Results:

A significant difference was observed in ANI values between the SB (higher ANI) and the PSI groups during skull pin insertion, P < 0.001 and P = 0.003 for ANIi and ANIm, respectively. Similarly, a significant difference was seen in HR and BP both within and between the two groups during skull pin insertion (P < 0.001 for both). The magnitude and duration of change were smaller in the SB group compared with the PSI group for the parameters studied. A strong negative linear correlation was noted between ANI and hemodynamic parameters.

Conclusions:

The changes in HR, BP, and ANI were significantly less with local anesthetic SB compared with PSI during skull pin insertion in patients undergoing supratentorial craniotomy.

The Effect of Intravenous Infusion of Dexmedetomidine to Prevent Bleeding During Functional Endoscopic Sinus Surgery: A Clinical Trial

Background

Bleeding during surgery can lead to serious complications. Methods and drugs to control bleeding are always important both for the surgeon and anesthesiologist, especially in endoscopic procedures. A lot of efforts are made to optimize the surgical conditions for functional endoscopic sinus surgery. Induced hypotension is widely advocated to prevent bleeding and consequently to improve the quality of an operation . Amongst the pharmacological agents, dexmedetomidine is the most recently introduced drug to provide hypotensive anesthesia during functional endoscopic sinus surgery.

Objectives

The current study aimed at investigating the effects of intravenous infusion of dexmedetomidine on bleeding, nausea, awakening time, and other intravenous anesthetic doses during functional endoscopic sinus surgery.

Methods

Sixty patients aged 16 to 60 years with American society of anesthesiologists (ASA) class I or II in Imam Khomeini hospital of Ahvaz, Iran, who were the candidate for the elective functional endoscopic sinus surgery were enrolled in the current double-blind clinical trial. They were randomly divided into 2 groups: group D (receiving dexmedetomidine), and group N (receiving normal saline). Sampling was based on the block randomization method. In group D, a 1-μg/kg dexmedetomidine was injected during 10 minutes just before the induction. Then, 0.5 µg/ kg/ hour infusion was started. Both groups had the same induction and maintenance method as well as the drugs administered for general anesthesia induction. For maintenance, the patients received O₂ 50%: N₂O 50% and 100 μg/kg/minute of propofol and 0.2 μg/kg/minute of remifentanil. In group N, instead of dexmedetomidine in bolus and maintenance, normal saline was used with the same volume. Mean arterial pressure was maintained between 65 to 75 mmHg. The incidence of bleeding, nausea and vomiting after surgery, the amount of maintenance drugs, and awakening time were recorded in a checklist.

Results

The intravenous use of dexmedetomidine significantly reduced the amount of bleeding (P < 0.0001); in addition, the need for opioids (P < 0.0001) and intravenous anesthetics significantly decreased (P = 0.001). Awakening time was significantly longer (P = 0.001), but its effect on postoperative nausea and vomiting was not significant (P = 0.052).

Conclusions

The current study showed that although propofol and remifentanil compounds can control hemodynamic state, but intravenous infusion of dexmedetomidine during the functional endoscopic sinus surgery reduced the amount of bleeding more significantly. It also reduced the dosage of maintenance drugs.