Journal of Anaesthesiology, Clinical Pharmacology最新文献

Background and aims: Opioids are known to reduce the propofol dose required to blunt movement and hemodynamic responses to noxious stimuli. However, the optimal propofol dosage for smooth induction remains unclear, particularly in the Indian population where pharmacokinetic data is limited. This study aims to evaluate the effect site concentration of propofol in conjunction with varying fentanyl doses, with relation to loss of consciousness and bispectral index (BIS) values during anesthesia induction using target-controlled infusion (TCI).

Material and methods: Sixty patients aged 20-50 years, with American Society of Anesthesiologists physical status I and II, scheduled for elective surgeries under general anesthesia were included. Anesthesia induction was performed using a TCI pump with propofol based on the Schnider model, starting at 1.5 µg/ml and increasing at 0.5 µg/ml until loss of verbal response, followed by 0.2 µg/ml till the final clinical endpoint was reached. Patients received either 1 or 2 µg/kg fentanyl or no fentanyl. Endpoints were assessed using the BIS monitor and Modified Observer Assessment of Alertness/Sedation Scale score.

Results: Hemodynamic parameters were stable across groups. The effect site concentration of propofol for loss of response to noxious stimuli was significantly lower in the fentanyl groups (fentanyl 1 µg/kg- 2.90 ± 0.1947 µg/ml, fentanyl 2 µg/kg- 2.445 ± 0.23 µg/ml) compared to the propofol alone group (4.205 ± 0.909 µg/ml) (P = 0.0001). Similar results were observed for loss of response to verbal commands. The effect site concentration at BIS 60 corresponded to loss of response to noxious stimuli.

Conclusions: Propofol effect site concentrations were significantly higher without fentanyl. The findings contribute valuable data for refining pharmacokinetic models tailored to individual patient needs.

Background and aim: Genicular nerve block has recently become a promising treatment option along with radiofrequency ablation in the management of osteoarthritis of the knee.

Material and methods: Sixty patients of age above 50 years with a pain pattern consistent with osteoarthritis of the knee, with their X-ray knee joint findings corresponding to their clinical symptoms, and with a failure to respond to conservative treatment were included in this study. The patients were divided into two groups of 30 each as follows: group I: patients were administered fluoroscope-guided radiofrequency ablation of genicular nerve using RF electrode set to a temperature of 60℃ for 120 sec and group II: patients were administered fluoroscope-guided genicular nerve block using 9 ml drug solution comprising 8 ml of 0.25% bupivacaine plus 1 ml (40 mg) of methylprednisolone.

Results: Both techniques of knee injection were effective and provided good pain relief to the patients with symptomatic osteoarthritis of the knee. Pain scores were clinically less in group I compared to group II at all time intervals of the study period. However, they were statistically significant between the two groups at 2, 3, 6, and 12 months (P < 0.05) with lesser Numerical Rating Scale in group I compared to group II. Western Ontario and McMaster Universities osteoarthritis index was clinically better in group I at all time intervals of the study period, but was statistically significant at 2 weeks, 1 month, and 12 months after the procedure (P < 0.05).

Conclusions: Fluoroscope-guided radiofrequency ablation of genicular nerve is better than fluoroscope-guided genicular nerve block in terms of improvement in pain score, physical status, and patient satisfaction.

Background and aims: Blockbuster^TM laryngeal mask (LM), a newer supraglottic airway device, is claimed to be an efficient conduit for blind tracheal intubation. It comes with a specialized Blockbuster tube. A conventional silicone wire-reinforced tube can be an alternative to the Blockbuster tube. This study was conducted to compare the first pass success rate of endotracheal intubation with Blockbuster tube and silicone wire reinforced tube through Blockbuster^TM laryngeal mask in children.

Material and methods: This study was carried out in 90 children, aged between 3 and 12 years, belonging to ASA- I and II randomized into two groups. After induction, group I was intubated with a Blockbuster tube and group II with a silicone wire-reinforced tube through Blockbuster^TM laryngeal mask. First pass success rate, maneuvers needed, number of attempts, time for intubation, hemodynamic changes, and complications were recorded.

Results: Group I had a higher first-pass success rate than group II (73.3% vs. 37.8%, P = 0.002), need for maneuvers was less in group I as compared to group II (26.7% vs. 62.2%, P = 0.000). The need for subsequent attempts for successful intubation was less in group I as compared to group II (24.5% vs. 57.7%, P = 0.002). The time taken to intubate in group I was 28.0 ± 2.2 s and in group II was 36.6 ± 2.3 s (P < 0.001). The two groups were comparable with respect to hemodynamic changes and complications.

Conclusion: Silicone wire reinforced tube may not be a suitable alternative to Blockbuster ETT for endotracheal intubation through Blockbuster^TM laryngeal mask in children.

Background and aims: Pain on propofol injection (POPI) leads to intense patient discomfort during the induction of anesthesia. This study aimed to compare the efficacy of intravenous dexmedetomidine and topical cold thermotherapy in the relief of POPI.

Material and methods: This randomized controlled trial was conducted on 274 adults undergoing elective surgery under general anesthesia. Patients received dexmedetomidine (0.25 µg/kg) following the application of a tourniquet proximal to the intravenous cannulation site for 30 s (Group D, n = 137), or an ice pack gel (260 mm × 125 mm) was applied proximal to the site of the cannula for 1 min (Group T, n = 137). The primary objective was to assess and compare the incidence and severity of POPI using the McCrirrick and Hunter Scale. The secondary objectives included the comparison of the induction dose of propofol and the hemodynamics (heart rate, blood pressure) at induction, along with the assessment of the presence of discomfort following ice gel pack application.

Results: The incidence of pain was greater in Group D as compared to Group T (54.74% v/s 29.17%, P < 0.001). The severity of pain was also greater in Group D as compared to Group T, (pain scores ≥2, Group D v/s T,33 (24%) v/s 5 (3.6%), P < 0.001). The incidence of pain scores 1 and 2 was also higher in Group D as compared to Group T [pain score 1: 42 (30.7%) v/s 35 (25.5%), P = 0.348; pain score 2: 27 (19.7%) v/s 4 (2.9%), P < 0.001]. There was no significant difference in the induction dose of propofol and hemodynamic variables between the groups.

Conclusion: The application of ice gel pack thermotherapy is associated with a significant reduction in POPI as compared to pre-treatment with dexmedetomidine (0.25 µg/kg), with no significant adverse effects.

Melanocytic neuroectodermal tumor of infancy (MNTI) is a rare, benign neoplasm involving the jaw. It is characterized by a high rate of recurrence and locally aggressive enlargement. This condition often leads to facial asymmetry and difficulty in airway management during surgical excision. Due to its rarity, there are no established guidelines for the perioperative management of MNTI. We describe the successful airway and anaesthetic management of three paediatric cases of MNTI. These cases highlight the complexities of airway management in paediatric patients with limited oral space and facial asymmetry. The anaesthetic approach prioritized meticulous preparation for potential difficult airway scenarios, including obtaining high-risk consent, assembling appropriate equipment, and premedication with ketamine and glycopyrrolate. Inhalational induction with sevoflurane was employed, and video laryngoscopy was used to aid intubation. Muscle relaxation and analgesia were carefully managed intraoperatively, with an emphasis on minimizing opioid usage postoperatively. The cases illustrate the importance of teamwork and multidisciplinary collaboration in managing challenging paediatric airway scenarios. This series contributes to the understanding of anaesthetic considerations in MNTI cases and underscores the significance of thorough preparation and coordination in optimizing patient outcomes.

Background and aims: The volume and concentration of local anaesthetic are particularly importance for the success of a block in providing analgesia. To improve safety, the goal should be the minimum dose of local anaesthetic capable of providing maximum effectiveness. Interfascial plane blocks are considered volume blocks, and a higher volume of local anaesthetic needs to be injected into the fascial plane to achieve the desired effect. Reducing the local anaesthetic concentration may limit the total dose administered without changing the volume injected.

Material and methods: Sixty children aged 8-12 years undergoing hypospadias repair were included in the study. After the induction of general anaesthesia, Group I (n = 30) was given an ultrasound-guided sacral erector spinae block with 1 ml/kg of 0.125% bupivacaine, and Group II (n = 30) received the same block with 1 ml/kg of 0.25% bupivacaine. Postoperatively, when the visual analogue scale (VAS) score was ≥ 4, rescue analgesia was administered using intravenous paracetamol at 15 mg/kg. The primary objective was to compare the time to the first paracetamol rescue. Secondary objectives included intraoperative hemodynamic parameters, additional fentanyl consumption, postoperative visual analogue scores, and total analgesic consumption (paracetamol and ibuprofen) within 24 h.

Results: The mean time to the first paracetamol rescue was 20.0 h (standard deviation [SD]: 3) h in Group I and 22.5 h (SD: 3) h in Group II (P = 0.19) (mean difference 2.5 [95% CI: -6.46, 1.46]), with a Cohen's d value of 0.83. The postoperative VAS scores at different time points were similar between the two groups. Ibuprofen was not required by any patient. The mean postoperative analgesic consumption (paracetamol) was 385 mg (SD: 77.85) in Group I and 427.5 mg (SD: 31.22) in Group II (P = 0.32) (mean difference 42.5 [95% CI: 16.08, 89.96]), with a Cohen's d value of 0.71.

Conclusions: Bupivacaine 0.125% is as effective as 0.25% bupivacaine in terms of the time to first paracetamol rescue for sacral erector spinae block in paediatric patients undergoing hypospadias repair.