Cihangir Bicer

Dexmedetomidine and meperidine prevent postanaesthetic shivering

Background and objective: This placebo‐controlled study was performed to evaluate the efficacy of dexmedetomidine compared with meperidine and placebo in preventing postanaesthetic shivering. Methods: We studied 120 patients (ASA I‐II) scheduled for elective abdominal or orthopaedic surgery of about 1‐3 h duration. Forty patients in each group randomly received 1 μg kg−1 of dexmedetomidine, 0.5 mg kg−1 of meperidine or saline 0.9% as placebo, intravenously (i.v.). Mean arterial pressure, heart rate, oxygen saturation and central body temperature were measured. Extubation, awakening and orientation times, shivering, pain, recovery and sedation scores were recorded. Results: Postanaesthetic shivering was seen in 22 patients in the placebo group, four patients in the meperidine group and six patients in the dexmedetomidine group. Sedation scores were significantly higher in the dexmedetomidine group compared with meperidine and placebo groups. Both dexmedetomidine and meperidine caused a significantly prolonged extubation and awakening time compared with placebo. Also, dexmedetomidine caused a significantly prolonged orientation time compared with other two groups. Conclusion: Intraoperative intravenously administration of dexmedetomidine 1 μg kg−1 reduces postanaesthetic shivering as does meperidine 0.5 mg kg−1 in patients after major surgery.

The comparison of the effects of dexmedetomidine and midazolam sedation on electroencephalography in pediatric patients with febrile convulsion

Background:  When electroencephalogram (EEG) activity is recorded for diagnostic purposes, the effects of sedative drugs on EEG activity should be minimal. This study compares the sedative efficacy and EEG effects of dexmedetomidine and midazolam.

Comparison of the Effects of Dexmedetomidine Versus Fentanyl on Airway Reflexes and Hemodynamic Responses to Tracheal Extubation During Rhinoplasty: A Double-Blind, Randomized, Controlled Study

BACKGROUND Stimulation of various sites, from the nasal mucosa to the diaphragm, can evoke laryngospasm. To reduce airway reflexes, tracheal extubation should be performed while the patient is deeply anesthetized or with drugs that do not depress ventilation. However, tracheal extubation during rhinoplasty may be difficult because of the aspiration of blood and the possibility of laryngospasm. Dexmedetomidine and fentanyl both have sedative and analgesic effects, but dexmedetomidine has been reported to induce sedation without affecting respiratory status. OBJECTIVE The aim of this study was to compare the effects of dexmedetomidine and fentanyl on airway reflexes and hemodynamic responses to tracheal extubation in patients undergoing rhinoplasty. METHODS This double-blind, randomized, controlled study was conducted at the Erciyes University Medical Center, Kayseri, Turkey. Patients classified as American Society of Anesthesiologists physical status I or II who were undergoing elective rhinoplasty between January 2007 and June 2007 with general anesthesia were eligible for study entry. Using a sealed-envelope method, the patients were randomly divided into 2 groups (20 patients per group). Five minutes before extubation, patients received either dexmedetomidine 0.5 μg/kg in 100 mL of isotonic saline or fentanyl 1 μg/kg in 100 mL of isotonic saline intravenously. All patients were extubated by anesthesiologists who were blinded to the study drugs, and all were continuously monitored for 15 minutes after extubation. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and oxygen saturation using pulse oximetry (SpO2) were recorded before anesthesia, after drug administration, after skin incision, at the completion of surgery, and 1, 5, and 10 minutes before and after tracheal extubation. Any prevalence of laryngospasm, bronchospasm, or desaturation was recorded. RESULTS Forty patients (25 men, 15 women; mean [SD] age, 24.86 [7.43] years) were included in the study. Dexmedetomidine was associated with a significant increase in extubation quality compared with fentanyl, reflected in the prevalence of cough after extubation (85% [17/20] vs 30% [6/20] of patients, respectively; P = 0.001). There were no clinically significant decreases in HR, SBP, DBP, or SpO2 after extubation with dexmedetomidine or fentanyl. In the dexmedetomidine group, HR was not significantly increased after extubation; however, in the fentanyl group, HR was significantly increased compared with the preextubation values (all, P = 0.007). HR was significantly higher in the fentanyl group compared with the dexmedetomidine group at 1, 5, and 10 minutes after extubation (all, P = 0.003). Compared with preextubation values, SBP was significantly increased at 1 and 5 minutes after extubation in the dexmedetomidine group (both, P = 0.033) and at 1, 5, and 10 minutes after extubation in the fentanyl group (all, P = 0.033). The postoperative sedation scores and the extubation, awakening, and orientation times were not significantly different between the 2 groups. In the dexmedetomidine group, bradycardia (HR <45 beats/min) was observed in 2 patients and emesis was observed in 2 patients. In the fentanyl group, emesis was observed in 3 patients, bradycardia in 2 patients, vomiting in 1 patient, and shivering in 1 patient; vertigo was reported in 1 patient. There were no significant differences in the prevalence of adverse events between the 2 groups. CONCLUSION The findings in the present study suggest that dexmedetomidine 0.5 μg/kg IV, administered before extubation, was more effective in attenuating airway reflex responses to tracheal extubation and maintaining hemodynamic stability without prolonging recovery compared with fentanyl 1 μg/kg IV in these patients undergoing rhinoplasty.

The effects of intraoperative infusion of dexmedetomidine on early renal function after percutaneous nephrolithotomy

Background: Percutaneous nephrolithotomy (PCNL) may interfere with renal function because of continuous fluid irrigation and compression. The aim of this study was to evaluate the effects of an intraoperative infusion of dexmedetomidine on renal function in patients undergoing PCNL.

Comparison of 0.5% levobupivacaine, 0.5% bupivacaine, and 2% lidocaine for retrobulbar anesthesia in vitreoretinal surgery

PURPOSE The authors compared the efficacy of local anesthetics levobupivacaine, bupivacaine, and lidocaine for retrobulbar anesthesia in vitreoretinal surgery. METHODS A total of 135 patients presenting for vitreoretinal surgery under local anesthesia were included in the study. Patients were randomly allocated to one of three groups. Group LB patients received 5 mL of 0.5% levobupivacaine, Group L patients received 5 mL of 2% lidocaine, and Group B patients received 5 mL of 0.5% bupivacaine for retrobulbar anesthesia via inferotemporal injection. Sensory and motor block durations were recorded. Intraoperative and postoperative pain was assessed by using verbal pain scala. Anesthesia efficiency, patient and surgeon satisfaction, and akinesia were assessed by using point scales. Hemodynamic data and adverse events were recorded. RESULTS The demographic characteristics of patients, duration of surgery, and hemodynamic data in both groups were similar. The duration of motor and sensory block was longer in levobupivacaine and bupivacaine groups than lidocaine group. Pain on injection was found more frequent in Group L and Group B than Group LB and the difference between the Groups LB and B was significant (p<0.05). Surgeon and patient satisfaction were also higher and intraoperative pain was less in levobupivacaine group than lidocaine and bupivacaine groups. CONCLUSIONS Levobupivacaine provides longer motor and sensory block duration and higher surgeon and patient satisfaction than lidocaine and bupivacaine when used for retrobulbar anesthesia in vitreoretinal surgery.

Comparison of the effects of ketamine or lidocaine on fentanyl-induced cough in patients undergoing surgery: A prospective, double-blind, randomized, placebo-controlled study.

BACKGROUND Fentanyl-induced cough is common but has not been viewed as a serious anesthetic problem. However, the cough may be explosive at times, may require immediate intervention, and may be associated with undesirable increases in intracranial, intraocular, and intra-abdominal pressures. Prevention of fentanylinduced cough in such situations is of paramount importance. Ketamine, at concentrations achieved with standard clinical doses, has a direct relaxant effect on airway smooth muscle. OBJECTIVE This study was designed to assess the effects of ketamine or lidocaine on fentanyl-induced cough. METHODS This double-blind, randomized, placebo-controlled study was conducted at the Erciyes University Medical School, Kayseri, Turkey. Consecutive adult patients aged 18 to 65 years and classified as American Society of Anesthesiologists physical status I or II who were undergoing elective surgery with general anesthesia were enrolled. Patients were randomly allocated equally into 3 groups to receive lidocaine 1 mg/kg, ketamine 0.5 μg/kg, or placebo intravenously 1 minute before fentanyl administration. Following intravenous fentanyl (1.5 μg/kg over 2 seconds) injection, an observer, unaware of the type of medication given to the patients, recorded the number of episodes of coughing, if any. Any episode of cough was classified as coughing and graded by investigators blinded to treatment as mild (1-2 coughs), moderate (3-4), or severe (≥5). Blood pressure, heart rate, pulse oximetry oxygen saturation (SpO2), and adverse effects (AEs) were recorded. RESULTS A total of 368 patients were approached for inclusion; 300 patients met the inclusion criteria and were enrolled in the study. No patients in the ketamine group had cough. The frequency of cough was significantly lower in the lidocaine (11/100 [11%]; P = 0.024) and ketamine (0/100; P = 0.001) groups compared with the placebo group (23/100 [23%]). The intensity of cough was significantly lower in the lidocaine (mild, 7/100 [7%]; moderate, 4/100 [4%]; P = 0.037) and ketamine (0/100; P < 0.001) groups compared with the placebo group (mild, 10/100 [10%]; moderate, 12/100 [12%]; severe, 1/100 [1%]). Severe cough (≥5) was observed in 1 patient in the placebo group. Incidence and intensity of cough were significantly decreased in the ketamine group compared with the lidocaine group (incidence, P = 0.001; intensity, P = 0.003). There were no significant differences between groups with respect to systolic blood pressure, diastolic blood pressure, heart rate, SpO2, and AEs. CONCLUSION Intravenous ketamine (0.5 mg/kg) significantly reduced the reflex cough induced by fentanyl compared with lidocaine and placebo, and was well tolerated.

nasal and Buccal Treatment of Midazolam in epileptic seizures in pediatrics

Acute seizure and status epilepticus constitute major medical emergencies in children. Four to six percent of children will have at least one seizure in the first 16 years of life. Status epilepticus is a common neurological emergency in childhood and is associated with significant morbidity and mortality. The early application of antiepileptic treatment is very important. Because early treatment prevents the status epilepticus formation and shortens the duration of seizure activity. For this reason administration of anticonvulsant therapy in the prehospital setting is very important. Seizures generally begin outside the hospital, and thus parents and caregivers need simple, safe and effective treatment options to ensure early intervention. The only special preparation used for this purpose is rectal diazepam but has some disadvantages. Midazolam is a safe, short-acting benzodiazepin. It is suitable to use oral, buccal, nasal, im and iv routes. This provides a wide area for clinical applications. Recently there are many clinical studies about the usage of nasal and buccal midazolam for treatment of pediatric epileptic seizures. The nasal and buccal applications in pediatric seizures are very practical and effective. Parents and caregivers can apply easily outside the hospital.

Incidental Finding of Froin Syndrome during Spinal Anesthesia in a 72-Year-OldPatient

Froin Syndrome is characterized with xanthochromic CSF, high CSF protein content, complete blockage of CSF circulation. We reported our case of Froin Syndrome, a quite rare entity, with its radiologic features and characteristics of CSF biochemistry in the light of literature.

Comparison of preincisional infiltrated levobupivacaine and ropivacaine for acute postoperative pain relief after septorhinoplasty.

BACKGROUND To maintain a high standard of patient care, it is essential to provide adequate pain management in patients who undergo nasal surgery. Levobupivacaine and ropivacaine are relatively new long-acting local anesthetics. OBJECTIVE The aim of this study was to compare the analgesic effect and blood loss of preincisional levobupivacaine HCl 0.25% and ropivacaine HCl 0.375% in patients undergoing septorhinoplasty. METHODS Sixty American Society of Anesthesiologists (ASA) I and II patients (18-55 years old) who were scheduled for elective open technique septorhinoplasty under general anesthesia were recruited for this study. The anesthetic technique was standardized for both groups. Preoperative and postoperative hemoglobin levels were recorded for all patients. Patients were assigned randomly to 1 of 2 study groups, and preincisional surgical field infiltration with 5 mL of 0.5% levobupivacaine plus 5 mL of 0.9% saline (group L; n = 30) or 5 mL of 0.75% ropivacaine plus 5 mL of 0.9% saline (group R; n = 30) was performed by the same surgeon. The degree of pain was measured by visual analogue scale (VAS) for pain and recorded at multiple time points in all patients after surgery. RESULTS The analgesic effect at 2 hours in the postanesthesia care unit (PACU) and at 24 hours postoperatively did not differ significantly between the 2 local anesthetics (P > 0.05). Pain scores of patients decreased after the 24 hours in levobupivacaine group and ropivacaine group when compared with 0-minute VAS values, and this was statistically significant (P < 0.05). No significant difference was observed between groups with respect to the preoperative and postoperative hemoglobin (P = 0.767 and 0.824, respectively) values. CONCLUSIONS Local tissue infiltration with 0.25% levobupivacaine or 0.375% ropivacaine is similarly effective in reducing the postoperative pain associated with septorhinoplasty.

Effects of naloxone and flumazenil on antinociceptive action of acetaminophen in rats

BACKGROUND Studies of acetaminophen suggest that multiple nociceptive pathways are involved in the drugs analgesic action. OBJECTIVE The purpose of this study was to determine whether naloxone and flumazenil were able to modify or antagonize the antinociceptive effect of acetaminophen in rats. METHODS Adult albino Wistar rats were used in the study and randomly allocated to 1 of 4 groups. The acetaminophen group (A group) was administered IP saline and then 300 mg/kg IP acetaminophen 5 minutes thereafter. The acetaminophen + naloxone group (AN group) was pretreated with 1 mg/kg IP naloxone, followed by 300 mg/kg IP acetaminophen 5 minutes later. The acetaminophen + flumazenil group (AF group) was pretreated with 1 mg/kg IP flumazenil, followed by 300 mg/kg IP acetaminophen 5 minutes later. The control group received 2.5 mL IP saline, followed by an additional 2.5 mL IP injection of saline 5 minutes later. The paw-withdrawal latency period of the rats was assessed by an investigator blinded to treatment using the hot-plate test at 30, 45, 60, and 90 minutes after administration of acetaminophen. RESULTS Thirty-two rats were evenly randomized by envelope method into 4 groups of 8 rats each. Baseline values for the A, AN, AF, and control groups were not significantly different (9.1 [2.3], 10.5 [2.7], 9.8 [3.0], and 8.9 [1.4] sec, respectively). In the AF group, flumazenil appeared to antagonize the analgesic effect exerted by the acetaminophen in the hot-plate test (30 min, 10.3 [3.7] sec; 45 min, 11.7 [5.1] sec; 60 min, 12.1 [5.1] sec; and 90 min, 12.2 [4.9] sec) and values were not significantly different from those obtained in the control group (30 min, 9.8 [2.2] sec; 45 min, 9.0 [1.6] sec; 60 min, 9.2 [1.6] sec; and 90 min, 8.5 [2.0] sec). In the AN group, naloxone did not significantly affect the values observed in the hot-plate test (30 min, 18.0 [4.5] sec; 45 min, 21.5 [7.8] sec; 60 min, 20.5 [5.9] sec; and 90 min, 22.3 [7.4] sec) and values at all time points were not significantly different from those obtained in the A group (30 min, 17.8 [7.6] sec; 45 min, 20.9 [6.9] sec; 60 min, 21.5 [7.3] sec; and 90 min, 23.8 [8.6] sec). All postbaseline values in the A and AN groups were significantly increased versus baseline and versus the control group values (all, P < 0.05). All postbaseline values in the A group were significantly greater than those in the AF group (all, P < 0.05). CONCLUSION Flumazenil antagonized the analgesic effect exerted by acetaminophen, while naloxone had no significant effect on acetaminophens antinociceptive action in this pain model in rats.