Effect of inflammatory response on in vivo competition between two chlamydial variants in the guinea pig model of inclusion conjunctivitis.

In order to study the interaction of variants in in vivo infection, we employed an azithromycin-resistant mutant (AZ(2)) and its wild-type parent (SP(6)) in the guinea pig model of Chlamydia caviae conjunctival infection. When each strain was inoculated individually into conjunctiva, both attained the same level of growth, but AZ(2) elicited less pathology. However, when equal numbers of the two strains were inoculated together into the guinea pig conjunctiva, SP(6) produced a significantly greater number of inclusion-forming units than AZ(2), and the pathology reflected that of a SP(6) monoinfection. The goal of this study was to further characterize the dynamics of concomitant infection of these two distinct variants, with particular emphasis on the impact of the host response on the in vivo growth of each organism and the development of pathology. Animals infected with AZ(2) had reduced conjunctival infiltration with CD45(+) cells and neutrophils as well as a reduced interleukin-8 (IL-8) response. Gene expression of gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), CCL2, and CCL5 was also significantly lower in AZ(2)-infected animals. The lower inflammatory response induced by AZ(2) was associated with its decreased ability to activate NF-κB via Toll-like receptor 2 (TLR2). In general, the inflammatory response in animals infected with both variants was greater than in infection with AZ(2) alone, resulting in lower numbers of AZ(2) than those of SP(6) in the mixed infection. Our results suggest that the ability to elicit an inflammatory response is an important factor in the dynamics of mixed infection with strains that display different pathological phenotypes.

Effect of N2O on nausea and vomiting via intraabdominal pressure.

BACKGROUND AND OBJECTIVE: In this study we aimed to investigate whether there is an effect of N2O on postoperative nausea and vomiting (PONV) via intraabdominal pressure (IAP). METHODS: A total of 40 patients with risk class ASA I-II and age ranging between 20 and 50 years were enrolled in the study. The patients were monitored for electrocardiography (ECG), peripheral oxygen saturation (SpO2), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), end-tidal carbon dioxide (ETCO2) and body temperature. IAP was measured by a central venous pressure manometer placed in the urine catheter. Heart rate (HR), SpO2, SBP, DBP, MBP, ETCO2, body temperature and IAP were measured before the induction of anesthesia and every 10 minutes throughout the operation. Nausea and vomiting were questioned at the first and second postoperative hours. The patients were randomly grouped into two groups. Induction in both groups was provided using 2 mg/kg propofol, 2 µg/kg fentanyl and 0.1 mg/kg vecuronium, and endotracheal intubation was performed. The maintenance of anesthesia was provided by 40 % O2 + 60 % N2O, 1-2 % sevoflurane and 50 µg fentanyl + 2 mg vecuronium every 45 minutes in the first group. In the second group, 60 % dry air was used instead of 60 % N2O. RESULTS: There was no significant difference in terms of HR, SpO2, SBP, MBP, ETCO2, body temperature, nausea-vomiting and IAP. CONCLUSIONS: In conclusion, we think that N2O usage during the general anesthesia in patients without intraabdominal problems may increase IAP level for some degree whereas it does not increase PONV. In addition, N2O usage does not change ETCO2 values (Tab. 3, Fig. 3, Ref. 32).

Comparison of the analgesic effect of betamethasone and diclofenac potassium in the management of postoperative haemorrhoidectomy pain.

BACKGROUND: Outpatient postoperative haemorrhoidectomy pain remains a difficult problem. The purpose of this study is to compare the results of the use of betamethasone with diclofenac potassium in postoperative pain following haemorrhoidectomy. MATERIAL AND METHODS: Closed haemorrhoidectomy was performed on 40 patients who were diagnosed grade III, grade IV haemorrhoid on physical examination. Patients were divided equally randomized into two groups, prospectively (betamethasone was used for 20 patients and diclofenac potassium was given for 20 patients). A verbal categorical scale was used to evaluate postoperative pain (for pain intensity, none=0, mild=1, moderate=2 and severe=3). RESULTS: The amount of narcotics required on postoperative first, second and third day were significantly less in the betamethasone group than in the diclofenac potassium group (P < 0.001) (Pearson Chi-Square test). CONCLUSION: Results indicate that use of betamethasone provides more effective analgesia than diclofenac potassium for postoperative pain management in the haemorrhoidectomy patient.

The effects of halothane and sevoflurane on QT dispersion.

QT dispersion is defined as the difference between QT (max) and QT (min) in the 12-lead surface ECG. It has been shown to reflect regional variations in ventricular repolarization and is significantly greater in patients with arrhythmic events than in those without them. The aim of this study was to examine the effects of halothane and sevoflurane on QT and QTc dispersion during inhalational induction of anaesthesia. The effects on QT and QTc dispersion of halothane and sevoflurane have been investigated during induction of anaesthesia. Forty-six ASA (American Society of Anaesthesiologists) physical status I-II patients, aged 16-50 years, undergoing general anaesthesia were randomly allocated to receive either halothane or sevoflurane. The mean baseline values for QT and QTc dispersion were not significantly different between the two groups (P > 0.05). QT dispersion was increased with halothane compared with baseline values (50 +/- 16 ms vs. 29 +/- 9 ms, P < 0.01) and after sevoflurane compared with baseline (48 +/- 15 vs. 33 +/- 8 ms, P < 0.01). Also, QTc dispersion was increased with halothane compared with baseline values (48 +/- 13 ms vs. 31 +/- 9 ms, P < 0.001) and after sevoflurane compared with baseline (50 +/- 14 vs. 40 +/- 11 ms, P < 0.01). The QTc interval did not change by both sevoflurane (443 +/- 7 vs. 431 +/- 21 ms, P > 0.05) and halothane (419 +/- 33 vs. 431 +/- 19 ms, P > 0.05) compared with baseline. Both halothane and sevoflurane cause myocardial repolarisation abnormalities in man in terms of increased QTc dispersion. This may be relevant in the aetiology of arrhythmias in patients during anaesthesia with halothane or sevoflurane.

The effect of CO2 insufflation rate on the postlaparoscopic shoulder pain.

Shoulder pain (SP) is frequently mentioned in recent literature following laparoscopic operations. In the literature, many causes have been declared to explain shoulder pain after CO2 insufflation, such as direct peritoneal irritation of the CO2 gas, excessive traction of the triangular ligament, and overstretching of the diaphragmatic muscle fibers due to the high rate of insufflation. This study was planned as multicentric, and 76 patients, aged between 35 to 45, were entered into the study. They were all selected by a randomized sampling method, with equal numbers of men and women, to achieve true evaluation. The low flow-rate (LFR) group was insufflated with 2.5 L/min and the high flow-rate (HFR) group with 7.5 L/min. All cases were evaluated by subjective pain classification on postoperative day 3. According to the subjective pain scale method, shoulder pain average was 23.9+/-3.1 in the LFR group and 55.4+/-6.5 in the HFR group. The difference between these groups was significant (p > 0.01). There is no significant difference for the operation time (LFR%: 64+/-15 minutes, HFR: 61+/-20 minutes, p > 0.05). Our results suggest that there is a significant statistical relation between the postoperative shoulder pain levels and increased insufflation rates. For this reason, low insufflation rate significantly reduces the shoulder pain but does not increase the operation time. Therefore, a low insufflation rate should be applied in all cases for patients' comfort and safety.

Effects of dexmedetomidine on the duration of anaesthesia and wakefulness in bupivacaine epidural block.

BACKGROUND: The purpose of this study was to examine the effects of intravenous dexmedetomidine on the duration of bupivacaine-induced epidural anaesthesia and level of wakefulness and the respective side-effects. METHODS: Sixty ASA I-II patients were included in the study. Consecutive patients were allocated to groups according to the last digit (odd/even) of their admission numbers. All patients had epidural anaesthesia with bupivacaine 0.5% performed by the same experienced anaesthesiologist. In the first group, the patients were administered intravenous dexmedetomidine infusion just after the epidural block and continued during the operation, while those in the second group were administered physiologic saline infusion at the same amount and duration. RESULTS: The recovery time of sensory block was significantly longer in the first group. The bispectral index values were lower in the first group than in the second. Also, heart rate was significantly lower in Group I than in Group II. Regarding side-effects, shivering was significantly less frequent in the first group, whereas there was a significant increase in the requirement of atropine in the first group as dexmedetomidine caused bradycardia. CONCLUSION: Intravenous administration of dexmedetomidine prolonged the duration of epidural anaesthesia, provided sedation and had few side-effects.

The effects of volatile anesthetics on the Q-Tc interval.

OBJECTIVE: To examine the effects of halothane, isoflurane, and sevoflurane on Q-Tc interval (corrected for heart rate) during inhalation induction of anesthesia. DESIGN: Prospective, double-blind, randomized study. SETTING: Departments of Cardiology and Anesthesiology in a university hospital. PARTICIPANTS: Patients undergoing noncardiac surgery. INTERVENTIONS: A total of 65 American Society of Anesthesiologists physical status I-II patients, aged 16 to 50 years, undergoing general anesthesia, were randomly allocated to receive halothane, isoflurane, or sevoflurane. MEASUREMENTS AND MAIN RESULTS: The time to reach the predetermined end-tidal concentrations of 3 minimum alveolar concentration was 6 to 10 minutes. When compared with preinduction values, heart rate decreased after halothane (p < 0.01) and sevoflurane (p < 0.05) administration; in contrast, heart rate increased after induction of anesthesia with isoflurane (p < 0.05). The mean QRS intervals were not significantly changed after halothane, isoflurane, or sevoflurane. The Q-Tc interval was increased with isoflurane compared with baseline (465 +/- 23 v 441 +/- 18 msec, p < 0.01), not changed with sevoflurane (441 +/- 17 v 434 +/- 19 ms, p > 0.05), and shortened with halothane (426 +/- 23 v 445 +/- 21 msec, p < 0.01). CONCLUSION: Sevoflurane or halothane may be preferred to isoflurane in patients with conditions that are known to induce a prolonged Q-Tc interval. The effects of Q-Tc interval changes resulting from different anesthetic agents on morbidity and the incidence of arrhythmias during anesthesia warrant further investigation.