Sevoflurane vs. TIVA in terms of middle ear pressure during laparoscopic surgery.

OBJECTIVES: The aim of this study was to investigate the effects of CO2 insufflation on the pressure of the middle ear cavity (PMEC) during laparoscopic surgery under total intravenous anesthesia (TIVA) with propofol or sevoflurane as an inhalational anesthetic maintenance. MATERIAL AND METHODS: Sixty patients who underwent laparoscopic/or non-laparoscopic surgery under general anesthesia were included in the study. For anesthetic maintenance with inhalation agents, 20 non-laparoscopic surgery patients in Group 1 were applied sevoflurane (2-2.5%). Forty patients who underwent laparoscopic surgery were randomized into two groups. Anesthesia was maintained with sevoflurane (2-2.5%) in twenty patients in Group 2 and the TIVA technique in 20 patients in Group 3. In Group 1, PMEC was measured before anesthesia, 10 and 30 min after endotracheal intubation, 10 min before extubation, and 15, 30, 60 min and 6 hours in the postoperative period. In Group 2 and 3, PMEC was measured before the anesthesia, 10 min after intubation, 10 and 30 min after CO2 insufflation, just before the CO2 elimination, 10 min before the extubation, and 15, 30, 60 min and 6 hours after extubation in the postoperative period. RESULTS: PMEC was significantly increased in Group 1 at 10 min after intubation, at 30 min of the operation, before extubation, and at postoperative 15 and 30 min (p < 0.05). In Group 3, differences between PMECs were detected at the 30th min of insufflation (p = 0.005), and during elimination (p = 0.035) compared to the initial measurement. Generally, the values remained positive in Group 1 and negative in Group 3. There was a significant difference between Group 1 and Group 3 at 10 min after the induction (p = 0.001). There was no statistically significant difference in PMECs between Group 2 and 3 patients undergoing laparoscopic surgery. CONCLUSIONS: Our results indicate that, in laparoscopic surgery, TIVA used for the maintenance of anesthesia did not increase the PMEC and the changes caused by sevoflurane were also in the normal range of middle ear pressures. In patients with previous ear surgery, if there is a need of classical surgical procedures in the future, sevoflurane anesthesia should not be the first choice due to its effects on PMEC, which cause it to be increased over 50 daPa, especially at 30 min after intubation. Patient characteristics including previous ear surgery should be considered in selecting the optimum anesthetic agents and technique.

The effects of midazolam and dexmedetomidine infusion on peri-operative anxiety in regional anesthesia.

BACKGROUND: This study aimed to compare the influences ofmidazolam and dexmedetomidine infusion on anxiety scores in patients undergoing surgery with regional anesthesia. METHODS: Eighty ASA I or II class patient undergoing elective surgery with regional anesthesia were included in the study. Permanent anxiety scores were determined using the State-Trait Anxiety Inventory (STAI)-1 and 2 one day before the surgery. In Group I patients, dexmedetomidine 0.5 micro g/kg basal infusion for 10 min and 0.5 micro g/kg/h for maintenance was administered. In Group II patients, midazolam infusion at a rate of 0.05 mg/kg for 10 min and 0.05 mg/kg/h for maintenance was administered. The sedation scores were determined every 5 min. The steady state anxiety scores of the patients were determined one day before, 30 min after operation, at the end of the operation, and at 30 min and day 7 postoperatively using STAI-1 score. Side effects were determined and recorded. RESULTS: Sedation scores were comparable in both of two treatment groups. Anxiety scores were maintained with drug infusions. The incidences of side effects were significantly decreased in midazolam group compared to the dexmedetomidine group. CONCLUSION: Midazolam infusion was found to be more appropriate and efficient than dexmedetomidine during regional anesthesia practice. Dexmedetomidine infusion should be cautiously used in regional anesthetic techniques performing symphathetic blockade.

The effects of tramadol and levobupivacaine infiltration on postoperative analgesia in functional endoscopic sinus surgery and septorhinoplasty.

OBJECTIVE: The aim of this prospective, randomized, double-blind study was to investigate the postoperative analgesic effects of levobupivacaine or tramadol infiltration administered prior to surgery in septorhinoplasty (SRP) or endoscopic sinus surgery (ESS). MATERIAL AND METHODS: Sixty ASA class I-III adult patients electively undergoing SRP or ESC were included the study. Induction of anesthesia was performed with propofol 2-2.5 mg/kg, rocuronium bromide 0.6 mg/kg and fentanyl 1 µg/kg i.v. Sevoflurane 2% with an N2O/O2 mixture (FiO2: 35%) was used for maintenance. Tramadol 0.5 mg/kg (Group T: n=20), levobupivacaine 0.25% (Group L: n=20) and lidocaine 1% (Group C: n=20) in a 1/200,000 adrenaline solution was infiltrated into the surgical area 10 min before the operation (5 mL for ESS and 10 mL for SRP). All patients received fentanyl (bolus dose: 15 µg and lockout interval: 10 min) with a patient-controlled analgesia device during the postoperative period. Pain was assessed using an 11-point visual analogue scale (VAS) every 4 h for the first 24 h. Analgesic requirements, opioid consumption and side effects in the postoperative period were recorded. RESULTS: There was a statistically significant decrease in postoperative fentanyl demand and consumption in patients receiving tramadol. Fentanyl doses in the 24 h period were 345.2±168.8 µg, 221.1±120.6 µg and 184.1±130.3 µg (p=0.002) for the Groups C, L and T, respectively. There were statistically significant differences in fentanyl requirements between the tramadol and control groups at the 16, 20 and 24 h time points (p=0.012, p=0.004 and p=0.002, respectively). The side effect profiles were similar. CONCLUSIONS: Our study indicates that the preemptive tramadol infiltration technique is an efficient, practical and safe alternative to levobupivacaine in ESS or SRP operations.

Comparative assessment of induction efficacy of propofol preparations.

OBJECTIVE: To compare the hypnotic effects (using Bispectral Index [BIS]), hemodynamic parameters, injection pain and quality of anesthesia during induction of anesthesia of the 3 commercial propofol preparations (Abbott Propofol, Abbott Laboratories), Pofol (Dongkook Pharm. Co. Ltd.), and Propofol 1% Fresenius (Fresenius Kabi). METHODS: After Ethics Committee Approval, a prospective, randomized, double-blind study was designed in Hacettepe University Hospitals Operating Theaters in 2005. The patients aged 18-65 years, American Society of Anesthesiologists (ASA) grades I and II scheduled for elective surgery under general anesthesia with orotracheal intubation. Ninety patients were randomized into 3 groups with 30 patients in each group. Propofol infusion rate was 2.5 mg. seconds(-1). Induction time and doses to reach BIS level of 50+/-10, injection pain, BIS values and hemodynamic parameters were recorded every minutes for the first 7 minutes and than every 2 minutes for 15 minutes. We used a special chart to assess the induction quality. RESULTS: Demographical parameters and ASA Physical status were similar in all groups. There were no significant differences in induction quality, induction time and doses, injection pain, BIS values and hemodynamic parameters. CONCLUSION: Abbott Propofol, Pofol and Propofol 1% Fresenius have similar effects on anesthesia induction quality and the cost should be taken into consideration when choosing the type of commercial formulation propofol emulsions.