Sener Demiroluk

Pulmonary mechanics during isoflurane, sevoflurane and desflurane anaesthesia

This study was designed to investigate the effects of desflurane on bronchial smooth muscle tone, following intubation and to compare these effects with isoflurane and sevoflurane. Patients were randomly divided into three groups to receive, isoflurane (n = 22), sevoflurane (n = 23), or desflurane (n = 22). Peak inspiratory pressure (PIP), respiratory resistance (Rr) and dynamic compliance (Cdyn) measurements were recorded at three time points; After the beginning of ventilation and before inhalation agent was started, following 5 min of ventilation with 1 MAC (minimum alveolar concentration) inhalation agent and following 5 min of 2 MAC inhalation agent. We found that all inhalation agents caused a significant decrease in Peak Inspiratory Pressure (PIP) and respiratory resistance (Rr), and an increase in dynamic compliance (Cdyn) at 1 MAC concentrations. When the agent concentration was increased to 2 MAC, desflurane caused a significant increase in Rr and PIP and a decrease in Cdyn. We concluded that desflurane, like isoflurane and sevoflurane, exhibits a bronchodilator effect at 1 MAC concentration. However, increasing the concentration to 2 MAC caused an increase in airway resistance with desflurane, whilst sevoflurane and isoflurane continued to have a bronchodilator effect.

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.

Evaluation of intravenous paracetamol administration on postoperative pain and recovery characteristics in patients undergoing laparoscopic cholecystectomy.

Purpose In this study, the effects of intravenous paracetamol treatment on early postoperative period analgesia and recovery characteristics after laparoscopic cholecystectomy have been evaluated. Methods Forty patients whose American Society of Anesthesiologists physical status I or II underwent laparoscopic cholecystectomy and randomly divided into 2 equal groups. In the first group, 1 g paracetamol was given to the patients intravenously after intubation before start of the surgery in 15 minutes. The 100 mL 0.9% NaCl was infused intravenously for the control group in 15 minutes. Postoperative pain was evaluated and recovery characteristics were evaluated. Results Verbal and visual pain scores of the paracetamol group were significantly lower than control group (P<0.05). First morphine requirement and total administered morphine dose and duration of staying in recovery room were significantly decreased in the paracetamol group (P<0.05). Conclusions Beside its effective analgesic properties, paracetamol administration during per operative period supports effective and faster recovery.

Systemic Inflammatory Response after Laparoscopic and Open Application of Adjustable Banding for Morbidly Obese Patients

Background: Surgical injury induces a systemic inflammatory metabolic-endocrine response that is proportional to the severity of the surgical stress. Compared with the conventional open method, laparoscopic surgery is mini-invasive and has decreased postoperative pain and length of hospitalization. The aim of this study was to investigate the systemic inflammatory response, after laparoscopic and open stoma-adjustable silicone band application, which is thought to be mediated by cytokines. Method: 30 morbidly obese patients underwent Swedish adjustable gastric banding (SAGB). 15 patients underwent laparoscopic (group 1) and 15 open SAGB (group 2). Mean operative time for the laparoscopic group was 70-110 min and for the laparotomy group 80-120 min. Gallbladders were not removed,and there were no systemic diseases in the patients.The intensity of surgical trauma was evaluated by measurement of metabolic and hormonal responses to the surgery. Plasma levels of C-reactive (CRP), haptoglobin, ceruloplasmin, albumin, transferrin, IL-6, malonic dialdehyde (MDA) and creatinine were measured before and after the operation. Results: CRP and IL-6 levels increased during and after laparoscopic and open SAGB. However, postoperative responses were significantly greater after open SAGB (group 2) (p<0.05). MDA level, an indicator of an oxidative trauma, was elevated in group 1 at the 6th postoperative hour but was significantly higher in group 2 at the 6th and 12th postoperative hours. The results were more significant in group 2 (p<0.05).There was no statistical difference between groups 1 and 2 in terms of albumin, creatinine, and transferrin levels before and after surgery. Conclusion: The systemic inflammatory res ponses after laparoscopic SAGB were significantly reduced compared with those after open SAGB.

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.

Respiratory mechanics in morbid obese patients with chronic obstructive pulmonary disease and hypertension during pneumoperitoneum

Background and objective: To evaluate the effects of pneumoperitoneum and the reverse Trendelenburg position on respiratory mechanics and blood-gases in morbid obese patients with chronic obstructive pulmonary disease and hypertension. Methods: Sixteen morbid obese patients with chronic obstructive pulmonary disease and hypertension were studied. Mean arterial pressure, heart rate, respiratory resistance, dynamic respiratory compliance and peak inspiratory pressures were measured at four time points: 5 min after induction of anaesthesia (T1), 5 min after insufflation of the peritoneum (T2), 5 min after adoption of a 20° reverse Trendelenburg position (T3), and 5 min after deflation of the peritoneum (T4). Arterial blood-gas status was measured at the same measuring points. Results: Respiratory compliance was 40 ± 12, 28 ± 8, 32 ± 8 and 37 ± 11 mL cmH2O−1 in T1, T2, T3 and T4, respectively. The changes were significant at T2, T3 and T4. Airway resistance and peak inspiratory pressures showed comparable changes throughout the study with that of respiratory compliance. Haemodynamic measurements showed no clinically significant changes in this study. Conclusions: In morbid obese patients with chronic obstructive pulmonary disease and hypertension, a 20° reverse Trendelenburg position improved respiratory mechanics and oxygenation without any apparent adverse effects on haemodynamics during laparoscopic gastric banding surgery.

Effects of pneumoperitoneum and positioning on respiratory mechanics in chronic obstructive pulmonary disease patients during Nissen fundoplication.

Background and Objective The aim of this study was to evaluate the effects of pneumoperitoneum and patient positioning on respiratory mechanics and blood gases in chronic obstructive pulmonary disease (COPD) patients during laparoscopic Nissen fundoplication. Methods After the approval of the Ethical Committee, 32 patients were divided into 2 groups as COPD patients (n=16) and normal patients (n=16). Dynamic respiratory compliance (Cdyn), airway resistance, and peak inspiratory pressure were monitored. Measurements were made in 5 time points: after intubation (intubation), Trendelenburg position (Trendelenburg), during laparoscopic Nissen fundoplication surgery after pneumoperitoneum with the Fowler position (Fowler), right before the desufflation with Fowler position (Fowler-end), and after the desufflation in supine position (supine). Samples of arterial blood gases were collected at the same periods. Results At all periods, there was a significant decrease in Cdyn and arterial oxygen pressure in 2 groups. Although pneumoperitoneum did not exist during Trendelenburg position, the Cdyn (38±13 mL cm H2O−1) found to be significantly decreased in COPD patients. In 2 groups, the lowest Cdyn value detected during the Fowler-end period was 43±8 mL cm H2O−1 in control group and 34±11 mL cm H2O−1 in COPD group. Whereas the pH decreased at Fowler, Fowler-end, and supine period, arterial carbon dioxide pressure increased (P<0.05). There was no difference for the other parameters. Conclusions In COPD patients, Trendelenburg position has negative effect on respiratory mechanics. Pneumoperitoneum and other positions have similar effect on respiratory mechanics in COPD and control patients.

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.

Effect of intra-abdominal pressure level on gastric intramucosal pH during pneumoperitoneum.

The present study was designed to examine the effect of intra-abdominal pressure level on gastric intramucosal pH using gastric tonometry during pneumoperitoneum. One hundred patients were prospectively randomized into 5 equal groups (N = 20 each). Intra-abdominal pressure levels were 8, 10, 12, 14, and 16 mm Hg in groups I, II, III, IV, and V, respectively. Intramucosal pH measurement was done 2 times: 30 minutes following insufflation and 1 hour after the ending of the surgery. In the first and second measurements, intramucosal pH values were found as 7.39 ± 0.02 and 7.36 ± 0.03 in group I; 7.41 ± 0.03 and 7.38 ± 0.03 in group II; 7.37 ± 0.03 and 7.37 ± 0.03 in group III; 7.36 ± 0.03 and 7.37 ± 0.03 in group IV; and 7.39 ± 0.03, 7.36 ± 0.03 in group V, respectively. Statistical significance was not found in the comparison of these values within the groups and between the groups (P > 0.005, for each). In conclusion, intra-abdominal pressure between 8 and 16 mm Hg did not cause significant difference in gastric intramucosal pH.

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%.