Role of ischemic modified albumin in the early diagnosis of increased intracranial pressure and brain death

AIM

Increased intracranial pressure following trauma and subsequent possible development of brain death are important factors for morbidity and mortality due to ischemic changes. We aimed to establish the role of ischemic modified albumin (IMA) in the early diagnosis of the process, starting with increased intracranial pressure and ending with brain death.

MATERIALS AND METHODS

Eighteen Wistar-Albino rats were divided into three groups; control (CG, n = 6), increased intracranial pressure (ICPG, n = 6), and brain death (BDG, n = 6). Intracranial pressure elevation and brain death were constituted with the inflation of a balloon of a Fogarty catheter in the epidural space. In all three groups, blood samples were drawn before the procedure, and at minutes 150 and 240 for IMA and malondialdehyde (MDA) analysis.

RESULTS

Serum IMA levels at 150 and 240 minutes were higher in ICPG than in CG (p < 0.05). IMA levels were similar in ICPG and BDG. Serum MDA levels at 150 and 240 minutes increased in ICPG and BDG groups compared to CG (p < 0.05). MDA levels were similar in ICP and BD groups.

CONCLUSION

IMA should be considered as a biochemical parameter in the process starting from increased intracranial pressure elevation and ending at brain death (Tab. 3, Fig. 5, Ref. 31).

The effects of dexmedetomidine on pulmonary artery pressure in experiment

AIM

The primary purpose of this study is to assess the effects of dexmedetomidine (DEX) infusion on pulmonary artery pressures (PAP), heart rate (HR), and mean arterial pressure (MAP) in pigs. The secondary purpose is to evaluate whether DEX infusion via the pulmonary artery has any beneficial effect over the peripheral IV route.

MATERIALS AND METHODS

Sixteen healthy male pigs (25-35 kg) scheduled for laparoscopy training were used in this study. The animals were randomly allocated into two groups: Group I (n = 9): A loading dose of 1 μg/kg DEX was administered over 10 minutes followed by an infusion of 0.5 μg/kg/hr for one hour via the pulmonary artery catheter. Group II (n = 7): A loading dose of 1 μg/kg DEX was administered over 10 minutes followed by an infusion of 0.5 μg/kg/hr for one hour via the peripheral venous catheter. Mean PAP, HR, MAP, SpO2, and ETCO2 were recorded at 5, 10, 15, 30, 45, and 60 minutes after the initiation of the DEX infusion.

RESULTS

Heart rate and MAP were similar in both groups at all time points. Also, neither the HR nor the MAP deviated from the basal values in Groups I and II at any time point. The mean PAP values were similar in Groups I and II, and in Group I, the mean PAP values were similar to Group I's basal value at all time points. However, in Group II, the mean PAP values at 5, 45, and 60 minutes were significantly lower than Group II's basal value (p = 0.023, p = 0.041, p = 0.015, respectively).

CONCLUSION

DEX infusion did not elevate the mean PAP and the results from the administration of DEX through the peripheral vein and pulmonary artery were similar (Tab. 3, Ref. 13).

Comparison of ephedrine and ketamine in prevention of injection pain and hypotension due to propofol induction

BACKGROUND AND OBJECTIVE

This prospective, double-blind, randomized, placebo-controlled study compares the effects of ephedrine and ketamine on injection pain, and hypotension from propofol.

METHODS

After obtaining the approval of the Ethics Committee, 75 patients (ASA I-II) scheduled for elective operations with general anaesthesia were divided into three groups. Saline 2 mL (Group S, n = 25), ketamine 0.5 mg kg(-1) (Group K, n = 25) or ephedrine 70 microg kg(-1) (Group E, n = 25) were administered over 5 s after tourniquet application. After releasing the tourniquet, propofol 2 mg kg(-1) was injected in 30 s. Pain was evaluated on a numerical scale (0-10) where 0 represented no pain and 10 the most severe pain possible. Systolic, diastolic blood pressures and heart rates were recorded preoperatively, 1 min after propofol injection, before intubation and 1, 2 and 3 min after intubation in all patients.

RESULTS

The incidences of pain in Groups S, E and K were similar (84%, 80% and 72%, respectively). The mean pain score in Group K (2.1, SD 3.1) was significantly lower than those of Groups S and E (4.9, SD 2.6 and 4.6, SD, 3.3, respectively) (P < 0.05). The systolic and diastolic blood pressure values in Group K (120 +/- 27 mmHg) and Group E (123 +/- 21 mmHg) before intubation were significantly higher than that of Group S (104 +/- 25 mmHg) (P < 0.05). There was no significant difference between the mean heart rate values of the groups.

CONCLUSIONS

Low dose ketamine or ephedrine pretreatment may prevent hypotension due to propofol induction. Despite the reduction in injection pain intensity after ketamine, the study drugs were found to be ineffective in lowering the injection pain incidence.

Evaluation of a local anaesthesia regimen using a subphrenic catheter after gynaecological laparoscopy

BACKGROUND AND OBJECTIVE

The purpose of intraperitoneal local anaesthetic administration is to block visceral nociceptive conduction and to provide an additional route of analgesia. The present study evaluates the effects of sequential injections of bupivacaine on postoperative pain through a subphrenic catheter.

METHODS

In this double-blinded controlled study, patients scheduled for gynaecological laparoscopy were randomly divided into two groups. One group received 20 mL of saline with 1:200000 epinephrine through a subphrenic catheter before the incision closure and at 4-hourly intervals for the first postoperative 20 h. The second group received 20 mL of bupivacaine 0.125% with 1:200000 epinephrine at the same injection times. Postoperative pain scores and consumption of analgesics were compared.

RESULTS

There were no statistical differences in pain scores at rest or incidence of shoulder pain between the two groups, but the patients of the bupivacaine group reported lower pain scores on coughing only in the first hour postoperatively (P = 0.007). Although the patients consumed comparable amounts of metamizole and ondansetron, the number of patients requiring supplemental meperidine and flurbiprofen in the bupivacaine group were significantly lower than in the saline group (P < 0.05).

CONCLUSIONS

This study demonstrates that intraperitoneal bupivacaine may reduce pain on coughing in the early postoperative period and the consumption of analgesics postoperatively. The subphrenic catheter technique had no impact upon pain at rest and shoulder-tip pain after gynaecological laparoscopy.

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.

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.