Yildiz Kose

Comparison of effects of remifentanil, alfentanil and fentanyl on cardiovascular responses to tracheal intubation in morbidly obese patients

BACKGROUND AND OBJECTIVE The effects of remifentanil, alfentanil and fentanyl were compared on cardiovascular responses to laryngoscopy and endotracheal intubation in morbidly obese patients. METHODS Eighty morbidly obese ASA I-II patients were included in the study. Patients were randomly divided into four groups to receive either 1 microgkg(-1) fentanyl (Group F), 10 microgkg(-1) alfentanil (A), 1 microgkg(-1) followed by an infusion of 0.5 pg kg min(-1) remifentanil (R) or saline (P). The patients corrected weight was used to calculate the drug doses. Body mass indices (range) were: 54.3 +/- 7.37 (49-78.4), 55.67 +/- 7.44 (48.5-78.4), 53.17 +/- 5.36 (48.1-63.2), and 56.3 +/- 6.09 (46.6-67.7) kg m(-2), in Groups F, R, A and P respectively. Systolic, diastolic and mean arterial pressures and heart rate were measured non-invasively at three time points, which were 2 min before induction, 2 min after induction and 2 min after endotracheal intubation. RESULTS After induction of anaesthesia, arterial pressures decreased significantly in all groups, but the decrease was more pronounced in Groups A and R. After induction, heart rate decreased significantly in all groups except in Group P. After intubation, haemodynamic responses were similar in the remifentanil, fentanyl and alfentanil groups and were within normal limits. In Group P, arterial pressures and heart rates were significantly higher. CONCLUSIONS Alfentanil, fentanyl and remifentanil in the doses described had similar effects in controlling the haemodynamic response to tracheal intubation in ASA I-II morbidly obese patients.

Total Intravenous Anesthesia versus Single Breath Technique and Anesthesia Maintenance with Sevoflurane for Bariatric Operations

Background: The choice of anesthetic technique for general anesthesia in morbidly obese patients remains controversial. We aimed to compare blood gases, recovery and hemodynamic parameters using TIVA and sevoflurane anesthesia in bariatric surgery. Methods: The study was performed with permission of the ethics committee.We studied 40 morbidly obese patients allocated to 2 groups. The total I.V. anesthesia (TIVA) group was named Group T, and the sevoflurane group was named Group S. In Group T, anesthesia induction was achieved with propofol. In Group S, anesthesia induction was achieved by sevoflurane with single breath technique, with maintenance provided with 1-2% volume sevoflurane. Student t, Chi square and ANOVA tests were used for data analysis; p-value <0.05 was considered statistically significant. Results: There was no significant difference between the 2 groups in demographic data, blood gas values and recovery characteristic. Hemodynamic values were significantly lower in Group T than Group S, during and after the operative period. Conclusion: While sevoflurane induction and maintenance is a suitable anesthetic modality for obese patients, TIVA can be applied easily in those patients possessing no extra risk factors other than morbid obesity.

The effects of pneumoperitoneum on respiratory mechanics during bariatric surgery.

Background:The aim of this study was to investigate the influence of laparoscopic and conventional open surgery on respiratory mechanics, and blood gases, and to determine convenient techniques from the point of view of intraoperative respiratory mechanics, for bariatric surgery. Method: 40 morbidly obese patients were divided into 2 groups, patients undergoing laparoscopy Group 1, and patients undergoing conventional open surgery Group 2. Resistance of airway, dynamic compliance, and peak inspiratory pressure were measured. Measurement was performed in 4 periods: a) after anesthesia induction, b) after pneumoperitoneum in the Group 1 and after incision in the Group 2, c) after gastric band placement, d) and 5 min before extubation. Blood gases were recorded concomitantly. Results: There was no significant difference between the 2 groups in values of blood gases and respiratory mechanics. Conclusion: In the morbidly obese, laparoscopic and open surgery did not cause a significant difference for respiratory mechanics when compared with each other.

The effects of pneumothorax on the respiratory mechanics during laparoscopic surgery.

Pneumothorax is rare but can be a severe complication of laparoscopic surgery. Diagnosis of pneumothorax in laparoscopy includes the sudden increase in end-tidal carbon dioxide (EtCO(2)) with a decrease in compliance and an abnormal increase in airway pressure. By these case reports, we recommend the simultaneous monitoring of airway pressures, dynamic compliance, and particularly, EtCO(2) for an immediate diagnosis and prompt treatment of pneumothorax.

Accidental subarachnoid injection of atracurium: A case report

ration (SpO2) were measured with a Millenia device (Millenia, Orlando, FL, USA). MAP and HR were 80 mmHg and 72 beat·min 1, respectively. A lumbar puncture was performed with the patient in the left lateral position. Under local anesthesia, a 22-gauge spinal needle was placed in the subarachnoid space at the L2–3 interspace, using a median approach. Its position was confirmed by the appearance of CSF oozing through the needle. When the anesthetist performing the block needed to fill the syringe being used, the nurse, by mistake, passed him an ampule containing 5 ml (50mg) of atracurium, instead of hyperbaric 1% bupivacaine solution. The content of the ampule was aspirated into the syringe and then 3ml fluid was injected into the subarachnoid space. The patient was placed in the supine position with a pillow under his shoulders and head. This technique usually produces analgesia up to the T8–10 dermatomes. At this stage, the patient complained of diplopia and blurred vision, and then a general feeling of discomfort. Hypotension and tachycardia occurred. MAP and HR were 40 mmHg and 130 beat·min 1, respectively. All of these changes occurred after the administration of the drug into the subarachnoid space. Intravenous crystalloid infusion was restarted as soon as possible. Two minutes after the subarachnoid administration of the drug, MAP and HR were normalized, and the patient’s feeling of discomfort had disappeared. MAP and HR were 75 mmHg and 80 beat·min 1, respectively. The patient continued to complain of diplopia and blurred vision. When an assessment of the level of analgesia to the pinprick test was made 5 min later, it was apparent that there was no analgesia. At the same time, the patient showed progressive and generalized muscle hypotonia. When the sudden hemodynamic occurred changes, SpO2 dropped to 94%. We started oxygen administration with a mask. Then, SpO2 was elevated to 100%.