Kenan Kaygusuz

A comparison of sedation with dexmedetomidine or propofol during shockwave lithotripsy: a randomized controlled trial.

BACKGROUND:Dexmedetomidine, because it has both sedative and analgesic properties, may be suitable for conscious sedation during painful procedures. Extracorporeal shockwave lithotripsy (ESWL) is a minimal to mildly painful procedure that requires conscious sedation. We thus evaluated the utility of dexmedetomidine compared with propofol during an ESWL procedure. METHODS:Forty-six patients were randomly allocated into two groups to receive either dexmedetomidine or propofol for elective ESWL. Dexmedetomidine was infused at 6 &mgr;g · kg−1 · h−1 for 10 min followed by an infusion rate of 0.2 &mgr;g · kg−1 · h−1. Propofol was infused at 6 mg · kg−1 · h−1 for 10 min followed by an infusion of 2.4 mg · kg−1 · h−1. Fentanyl 1 &mgr;g/kg IV was given to all patients 10 min before ESWL. Pain intensity was evaluated with a visual analog scale at 5-min intervals during ESWL (10–35 min). Sedation was determined using the Observers Assessment of Alertness/Sedation. The Observers Assessment of Alertness/ Sedation scores and hemodynamic and respiratory variables were recorded regularly during ESWL (35 min) and up to 85 min after. RESULTS:Forty patients were evaluated. Visual analog scale values with dexmedetomidine were significantly lower than those with propofol only at the 25–35 min assessments (P < 0.05). During sedation, the respiratory rate with dexmedetomidine was significantly slower but Spo2 was significantly higher than with propofol (P < 0.05). Other clinical variables were similar (P > 0.05). CONCLUSION:A combination of dexmedetomidine with fentanyl can be used safely and effectively for sedation and analgesia during ESWL.

Remifentanil compared with morphine for postoperative patient-controlled analgesia after major abdominal surgery: a randomized controlled trial

Background and objective: This randomized, double‐blinded clinical study was designed to compare the efficacy and safety of remifentanil and morphine administered using intravenous (i.v.) patient‐controlled analgesia (PCA) for postoperative analgesia after major abdominal surgery during the first 24 postoperative hours. Methods: Sixty‐nine patients were randomly allocated into two groups, each receiving remifentanil or morphine. The first group received i.v. remifentanil PCA with a loading dose of 45 μg, a maintenance dose of 1 μg min−1, a bolus dose of 15 μg and a lockout interval of 10 min during the first 24 postoperative hours. The second group received i.v. morphine PCA with a loading dose of 5 mg, a maintenance dose of 0.3 mg h−1, a bolus dose of 1 mg and a lockout interval of 15 min. Age, weight, sex, history of general anaesthesia, duration of surgery and time spent in the post‐anaesthesia care unit were recorded. Preoperative pulse rate, systolic and diastolic blood pressures (BP), respiration rate and arterial blood gases were collected. Pulmonary function was tested before induction of anaesthesia, as well as at 4 and 26 h after operation. Pulse rate, systolic and diastolic BP, respiration rate, arterial blood gases, sedation and visual analogue scores, and presence of side‐effects in the recovery room and on the ward for 24 h were recorded at 0, 1, 2, 4, 6, 12, 18 and 24 h after operation. Total drug use, number of boluses delivered, number of boluses demanded and delivery/demand ratio were collected. Results: Sixty patients were evaluated. The groups did not differ in age, weight, sex, history of general anaesthesia, duration of surgery or time spent in the recovery unit. There were also no clinically relevant differences between the groups with regard to haemodynamic and respiratory parameters as well as sedation and visual analogue scores (P > 0.05). More bolus doses were demanded and delivered and the delivery/demand ratio was significantly higher in the remifentanil group (P < 0.05). There was no finding suggesting acute opioid tolerance during remifentanil or morphine PCA. Conclusion: The i.v. remifentanil PCA with the chosen dosage regimen after abdominal surgery produces postoperative analgesia and has cardiovascular side‐effects similar to those achieved with i.v. morphine. Special attention must be given to respiratory depression during establishment of PCA with remifentanil.

Effects of Adding Dexmedetomidine to Levobupivacaine in Axillary Brachial Plexus Block

BACKGROUND Although several studies have described effects of dexmedetomidine on peripheral nerve blocks, to date there is limited knowledge available on the impact of dexmedetomidine adjunct to levobupivacaine in axillary brachial plexus block. OBJECTIVE In this study, we aimed to investigate the effects of adding dexmedetomidine to levobupivacaine for an axillary brachial plexus block. METHODS A total of 64 patients of American Society of Anesthesiologists physical status I/II scheduled to undergo forearm and hand surgery, in which an axillary block was used, were enrolled. The patients were randomly divided into 2 groups: in group L patients (n = 32), an axillary block was performed with 39 mL levobupivacaine 5% plus 1 mL of isotonic sodium chloride. In group D patients (n = 32), an axillary block was performed with 39 mL levobupivacaine 5% and 1 mL dexmedetomidine 1 μg/kg(-1) plus isotonic sodium chloride. Demographic data, mean arterial pressure (MAP), heart rate (HR), peripheral oxygen saturation (Spo2), sensory and motor block onset times and block durations, time to first analgesic use, total analgesic need, intraoperative verbal analog scale, postoperative visual analog scale (VAS) data, and side effects were recorded for each patient. RESULTS There were no significant differences in patient and surgery characteristics between the 2 groups. Sensory block onset time was shorter in group D (P < 0.05). Sensory and motor block duration and time to first analgesic use were significantly longer in group D (P < 0.05), and the total need for analgesics was lower in group D (P < 0.05). Intraoperative 5- and 10-minute verbal analog scale values and postoperative VAS value at 12 hours were significantly lower in group D (P < 0.05). Intraoperative MAP and HR values, except at 5 minutes and postoperatively at 10 and 30 minutes and 1 and 2 hours, were significantly lower in group D (P < 0.01). Bradycardia, hypotension, hypoxemia, nausea, vomiting, and any other side effects were not seen in any patients. CONCLUSIONS It was concluded in our study that adding dexmedetomidine to axillary brachial plexus block shortens sensory block onset time, increases the sensory and motor block duration and time to first analgesic use, and decreases total analgesic use with no side effects. ClinicalTrials.gov identifier ISRCTN67622282.

Acute amitraz intoxication: retrospective analysis of 45 cases.

Objective: To present special clinical and laboratory features of 45 cases (44 adult cases) who were intoxicated through oral route. Design: Retrospective study. Setting: Intensive care unit (ICU) of a university hospital. Patients: Forty-five patients admitted to the ICU of Cumhuriyet University Hospital. Results: Forty-five patients between 4 and 97 years of age were evaluated. Intoxication was the result of a suicide attempt in 67% of cases and accidental in 33% of cases. Unconsciousness, nausea and vomiting were the common initial symptoms. The major clinical findings in the ICU were bradycardia, myosis, hypothermia, hyperglycemia, hypotension, coma and respiratory depression. Blood glucose level was increased in 64% of cases. No problem was noted in the patient or the fetus in a pregnant, 27-year-old patient, who was intoxicated with 10 mL of 12.5% amitraz. The length of stay in the ICU was between 2 and 15 days. None of the patients died. All patients were discharged without neurological sequela. Conclusion: The prognosis of amitraz intoxications through oral route is benign and results in complete healing; however, we suggest that these cases should be well monitored and followed-up in ICUs.

The Effects of Intravenous Ephedrine During Spinal Anesthesia for Cesarean Delivery: A Randomized Controlled Trial

We designed a randomized, double-blinded study to determine the efficacy and safety of 0.5 mg/kg intravenous ephedrine for the prevention of hypotension during spinal anesthesia for cesarean delivery. Patients were randomly allocated into two groups: ephedrine group (n=21) and control group (n=21). Intravenous preload of 15 mL/kg lactated Ringers solution was given. Shortly after the spinal injection, ephedrine 0.5 mg/kg or saline was injected intravenous for 60 sec. The mean of highest and lowest heart rate in the ephedrine group was higher than those of control group (P<0.05). There were significant lower incidences of hypotension and nausea and vomiting in the ephedrine group compared with the control group (8 [38.1%] vs. 18 [85.7%]); (4 [19%] vs. 12 [57.1%], respectively) (P<0.05). The first rescue ephedrine time in the ephedrine group was significantly longer (14.9±7.1 min vs. 7.9±5.4 min) than that of the control group (P<0.05). Neonatal outcome were similar between the study groups. These findings suggest, the prophylactic bolus dose of 0.5 mg/kg intravenous ephedrine given at the time of intrathecal block after a crystalloid fluid preload, plus rescue boluses reduce the incidence of hypotension.

Addition of dexmedetomidine or lornoxicam to prilocaine in intravenous regional anaesthesia for hand or forearm surgery: a randomized controlled study.

AbstractBackground and objectives: Intravenous regional anaesthesia (IVRA) is a simple and cost-effective technique that is ideally suited for surgery involving the distal arm. This study compared the effect of lornoxicam or dexmedetomidine in IVRA with prilocaine in patients who underwent hand or forearm surgery. Methods: This randomized, double-blind study enrolled 75 patients scheduled for hand or forearm surgery. IVRA was achieved with 2% prilocaine 3 mg/kg in the control group (n = 25), 2% prilocaine 3 mg/kg plus dexmedetomidine 0.5 μg/kg in the dexmedetomidine group (n = 25), and 2% prilocaine 3 mg/kg plus lornoxicam 8 mg in the lornoxicam group (n = 25). In all groups, 0.9% NaCl solution was added to make up a total volume of 40 mL. Sensory and motor block onset and recovery times, haemodynamic variables, visual analogue scale (VAS) pain and sedation scores, duration of analgesia, total analgesic consumption over 24 hours, adverse effects and quality of anaesthesia were recorded. Results: Sensory block onset was shorter and sensory block recovery time longer in the dexmedetomidine group compared with the lornoxicam and control groups (p < 0.05). Sensory and motor block recovery times and duration of analgesia for tourniquet were prolonged in the dexmedetomidine and lornoxicam groups compared with the control group (p < 0.05). Median VAS scores for tourniquet pain in the dexmedetomidine and lornoxicam groups were lower than that of the control group at 15 and 30 minutes (p < 0.05). Postoperatively, the duration of analgesia time was longer and median VAS scores were lower during the first 12 hours in the dexmedetomidine and lornoxicam groups compared with the control group (p < 0.05). Total analgesic consumption over 24 hours was lower in the dexmedetomidine and lornoxicam groups compared with the control group (p < 0.05). Anaesthesia quality as determined by the anaesthesiologist was better in the dexmedetomidine and lornoxicam group than in the control group (p < 0.05). Conclusions: Addition of dexmedetomidine or lornoxicam to prilocaine in IVRA decreased VAS pain scores, improved anaesthesia quality and decreased analgesic requirement. We suggest that addition of dexmedetomidine or lornoxicam at the doses used in this study to IVRA with prilocaine in this setting can be useful without causing adverse effects. No hypotension, bradycardia or hypoxia requiring treatment was seen in any of the patients. Addition of dexmedetomidine had a more potent effect, shortening sensory block onset time and prolonging sensory block recovery time more than lornoxicam.

Thoracic paravertebral block for postoperative pain management in percutaneous nephrolithotomy patients: a randomized controlled clinical trial.

Objective: To investigate the effect of thoracic paravertebral block (PVB) on pain control and morphine consumption in percutaneous nephrolithotomy operations. Subjects and Methods: This randomized controlled clinical study was performed on 60 American Society of Anesthesiologists (ASA) I-II patients between the ages of 18 and 60 years who underwent percutaneous nephrolithotomy with approval of the ethical committee and written consent of the patients. Patients were randomly allocated into two groups: group P had 4 ml of 0.5% levobupivacaine injected at each of the T10, T11, and T12 paravertebral spaces and a standard PVB, and group C received 4 ml of 0.9% NaCl solution. All patients were given standard general anesthesia. The follow-up of saturation, heart rate, peripheral oxygen, and blood pressure values was recorded before induction, intraoperatively, and postoperatively. At postoperative 1, 2, 6, 12, and 24 h, the visual analog scale (VAS), Ramsey sedation score, respiratory rate, and 24-hour total morphine consumption were recorded. In addition, side effects and satisfaction of patients were recorded. Results: VAS scores and total morphine consumption were lower in group P than in group C: 2.3 vs. 4.3 and 22.3 vs. 43.2 mg, respectively (p < 0.05). The level of satisfaction was higher in group P than group C. Differences between groups in other parameters were not significant. Conclusions: Thoracic PVB with levobupivacaine provided a good postoperative analgesia and increased patient satisfaction for those who underwent percutaneous nephrolithotomy.

Hypotensive anaesthesia with remifentanil combined with desflurane or isoflurane in tympanoplasty or endoscopic sinus surgery : a randomised, controlled trial

OBJECTIVE To compare the effect of remifentanil combined with desflurane or isoflurane on the quality of the operative field and surgical conditions, blood loss, and recovery during tympanoplasty or endoscopic sinus surgery. DESIGN Randomised, double-blinded clinical study. SUBJECTS Sixty-four patients were scheduled for elective tympanoplasty or endoscopic sinus surgery. The patients were randomly divided into two groups: desflurane or isoflurane. After anaesthesia induction, all patients received a continuous remifentanil infusion of 0.2-0.5 microg/kg/min until a mean arterial pressure of 65-75 mmHg was achieved. Heart rate and mean arterial pressure were recorded throughout anaesthesia. Blood loss was measured at the end of surgery. Achievement of a bloodless operative field was rated on a 100 mm visual analogue scale. Following completion of surgery, the time to extubation and to achievement of an Aldrete score of nine or more was recorded. RESULTS Sixty-three patients were evaluated. The total dose of remifentanil and the total blood loss were similar in both groups (p > 0.05). Time to extubation and to an Aldrete score of nine or more for the desflurane group was significantly less than for the isoflurane group (p 0.05). CONCLUSION Although desflurane and isoflurane both enabled good surgical conditions (in terms of quality of operative field) and convenient induction of hypotension for tympanoplasty and endoscopic sinus surgery, the recovery characteristics of desflurane were better than those of isoflurane. Therefore, desflurane may be preferable to isoflurane in such circumstances.

Intravenous Amitraz Poisoning

Amitraz, a derivative of dimethylformamidine, is an acariside and insecticide used to control parasites in animals. Amitraz inhibits monoamine oxidase and prostaglandin synthesis and is an alpha-2 adrenergic agonist. Xylene, a mixture of o-, m-, and p-dimethylbenzene, is widely used in industry. A 22-year-old woman was poisoned by an intravenous injection of 5–6 mL of an amitraz formulation (amitraz 12.5% + xylene 57.5%). Clinical findings were coma (Glasgow coma score 3), respiratory depression, hypotension, bradycardia, hematuria, and edema and hyperemia at the injection site. Although her coma and other symptoms quickly resolved, as has been seen in oral and dermal amitraz poisoning, intoxication with higher doses occurring from intravenous injection may result in more serious problems.

Controlled Hypotension With Desflurane Combined With Esmolol or Dexmedetomidine During Tympanoplasty in Adults: A Double-Blind, Randomized, Controlled Trial

BACKGROUND Controlled hypotension is a technique that is used to limit intraoperative blood loss to provide the best possible surgical field during surgery. OBJECTIVE The aim of this double-blind, randomized, controlled study was to compare the effects of desflurane combined with esmolol or dexmedetomidine on the amount of blood in the surgical field, recovery time, and tolerability in adult patients undergoing tympanoplasty. METHODS Turkish patients aged 18 to 60 years, classified as American Society of Anesthesiologists physical status I or II, who were scheduled for tympanoplasty were randomly divided into 2 groups: the esmolol group or the dexmedetomidine group. After the anesthesia induction in the esmolol group, a loading dose of esmolol was infused intravenously over 1 minute at 1 mg/kg, followed by a maintenance rate of 0.4 to 0.8 mg/ kg/h. In the dexmedetomidine group, a loading dose of dexmedetomidine was infused intravenously over 10 minutes at a rate of 1 μg/kg, followed by a maintenance rate of 0.4 to 0.8 μg/kg/h. The infusion rates were then titrated to maintain mean arterial pressure (MAP) of 65 to 75 mm Hg. General anesthesia was maintained with desflurane 4% to 6%. Heart rate (HR) and MAP were recorded during anesthesia. The following 6-point scale was used to assess the amount of bleeding in the operative field: 0 = no bleeding, a virtually bloodless field; 1 = bleeding that was so mild that it was not a surgical nuisance; 2 = moderate bleeding that was a nuisance but did not interfere with accurate dissection; 3 = moderate bleeding that moderately compromised surgical dissection; 4 = bleeding that was heavy but controllable and that significantly interfered with surgical dissection; and 5 = massive bleeding that was uncontrollable and made dissection impossible. Scores ≤2 were considered to be optimal surgical conditions. The sedation score was determined at 15, 30, and 60 minutes after tracheal extubation using the following scale: 1 = anxious, agitated, or restless; 2 = cooperative, oriented, and tranquil; 3 = responsive to commands; 4 = asleep, but with brisk response to light, glabellar tap, or loud auditory stimulus; 5 = asleep, sluggish response to glabellar tap or auditory stimulus; and 6 = asleep, no response. Time to extubation and to total recovery from anesthesia (Aldrete score ≥9 on a scale of 0-10), adverse effects (eg, intraoperative hypotension [blood pressure <65 mm Hg], bradycardia [HR <50 beats/min]), intraoperative fentanyl consumption, and postoperative nausea and vomiting were recorded. Arterial blood gas analysis and kidney and liver function tests were conducted. All patients were evaluated by the same attending surgeon and anesthesiologist, both of whom were blinded to the administered study drugs. RESULTS Fifty-two consecutive white patients undergoing tympanoplasty were identified. Two patients had to be excluded because of hypertension and 2 refused to participate. Forty-eight patients were equally randomized to either the esmolol group (n = 24 [16 women, 8 men]; mean [SD] age, 38.4 [10.5] years) or the dexmedetomi-dine group (n = 24 [17 women, 7 men]; mean age, 35.5 [14.7] years). Sedation scores were not collected for 1 patient in the esmolol group; therefore, analysis was conducted for 23 patients. The median (range) of the scores for the amount of blood in the surgical field in the esmolol and dexmedetomidine groups was 1 (0-3) and 1 (0-2), respectively (P = NS). Mean intraoperative fentanyl consumption in the esmolol group was significantly higher than in the dexmedetomidine group (50.0 [3.0] vs 25.0 [2.5] μg/min; P = 0.002). In the esmolol group, the mean times to extubation and to recovery from anesthesia were significantly shorter than those of the dexmedetomidine group (7.0 [1.4] vs 9.1 [1.9] minutes, respectively; 5.9 [2.1] vs 7.9 [2.3] minutes; both, P = 0.001). The mean sedation scores were significantly lower in the esmolol group (n = 23, because of intent-to-treat analysis) compared with the dexmedetomidine group at 15 minutes (2.5 [0.6] vs 3.6 [0.5]; P = 0.001) and 30 minutes (2.6 [0.6] vs 3.3 [0.6]; P = 0.001) postoperatively. No significant differences were found between the study groups in regard to blood urea nitrogen or creatinine concentration, aspartate aminotransferase or alanine aminotransferase activities, pH, partial pressure of carbon dioxide, or bicarbonate, before or after the operation. CONCLUSIONS Both esmolol and dexmedetomidine, combined with desflurane, provided an effective and well-tolerated method of achieving controlled hypotension to limit the amount of blood in the surgical field in these adult patients undergoing tympanoplasty. Esmolol was associated with significantly shorter extubation and recovery times and significantly less postoperative sedation compared with dexmedetomidine.