Background and objective Ischaemic colitis can be a serious complication after aortic surgery. The paucity of clinical symptoms makes its diagnosis particularly difficult and often delayed. Automated on-line tonometry is now proposed to monitor intestinal perfusion. This study was designed to assess the use of semi-continuous sigmoid-to-arterial [P(r-a)CO2] PCO2 gap monitoring in aortic surgery to detect colonic ischaemia.

Methods This prospective clinical study was realized at the University Hospital of Lille, France, including eight males scheduled for abdominal aortic aneurysm surgery. Intraoperative and postoperative P(r-a)CO2 values were compared with conventional monitoring and colonic mucosa aspect performed by sigmoidoscopy 48 h after surgery. Haemodynamic variables, O2 delivery (DO2), O2 consumption (VO2), O2 extraction (ERO2), lactate, P(v-a)CO2, P(r-a)CO2 were measured peroperatively and every 4 h during a 48-h postoperative period.

Results Intraoperative P(r-a)CO2 values increased significantly with the highest value (4.36 ± 3.42 kPa) observed during aortic clamping when DO2 was the most altered. P(r-a)CO2 continued to deteriorate after surgery with the maximal values between 8 (4.79 ± 3.85 kPa) and 12 (4.68 ± 3.26 kPa) h after surgery. This peak was associated with a significant ERO2 increase counterbalancing an increase of VO2 whereas DO2 tended to decrease. P(r-a)CO2 values began to decrease only at the end of the study. The highest values of P(r-a)CO2 were registered in patients with the most altered haemodynamic variables, severe ischaemic colitis along with higher hospital lengths of stay.

Conclusion Taken together, these data suggest that regional and automated capnometry may be easily used non-invasively to detect peroperative intestinal ischaemia in aortic surgery.

Intrathecal midazolam for use as a post-operative analgesic when given alone and in conjunction with intrathecal diamorphine was assessed. Fifty-two patients scheduled for elective Caesarean section under spinal anaesthesia were randomly allocated to receive either bupivacaine (B), bupivacaine with diamorphine (BD), bupivacaine with midazolam (BM) or all three (BMD) by intrathecal injection. Post-operatively, no differences in visual analogue score (VAS), sedation or post-operative nausea and vomiting (PONV) could be demonstrated between groups. Patient-controlled analgesia system (PCAS) usage was significantly greater in group B when compared with the other groups. Pruritus was commoner in patients receiving diamorphine (BMD & BD). No side effects attributable to midazolam were identified. Intrathecal midazolam at this dose appears safe and has clinically detectable analgesic properties. The duration of useful analgesia appears to be short-lived.

Background and objective Despite the fact that both general anaesthetics and hypotensive drugs influence autonomic nervous activity, no study has yet examined the heart rate variability during deliberate hypotension and general anaesthesia. The aim of this was to clarify the heart rate variability changes during deliberate hypotension under sevoflurane–nitrous oxide anaesthesia.

Methods Autonomic nervous system activity in patients (n = 45) subjected to deliberate hypotension during sevoflurane in nitrous oxide and oxygen anaesthesia was investigated by a heart rate variability measurement. Three different types of hypotensive drugs, a calcium channel antagonist (nicardipine), a nitric oxide donor (nitroglycerin) and a vasodilatory prostaglandin (alprostadil), were used to induce hypotension.

Results In all groups, low frequency power (sympathetic and parasympathetic indicator) and the ratio of low frequency to high frequency power (the LF/HF ratio, sympathetic indicator) were suppressed by induction of anaesthesia. In the control group, preanaesthesia low frequency power was 195 ± 139 ms2, the LF/HF ratio 10.3 ± 5.7, during anaesthesia 5 ± 9 ms2, 0.6 ± 0.8, respectively, P = 0.0093, 0.0034, whereas high frequency power (parasympathetic indicator) was not significantly changed. In those patients receiving nicardipine or nitroglycerin during anaesthesia, these variables did not differ significantly from those in the control group. During prostaglandin E1 infusion, high frequency power was higher compared with the values in the other groups (17 ± 12 ms2 in the prostaglandin group, 7 ± 6 ms2 in the nicardipine group, 6 ± 5 ms2 in the nitroglycerin group and 6 ± 4 ms2 in the control group, respectively, P = 0.0326, 0.0251, 0.0197).

Conclusions Sevoflurane in nitrous oxide and oxygen anaesthesia reduces sympathetic autonomic activity considerably, and the expected increases caused by hypotensive agents that occur in awake volunteers were not seen.

Background and objective The aim of the present study was to compare and assess the quality of analgesia, the safety and the side-effects after the use of a continuous, thoracic epidural infusion of sufentanil (5 μg h−1), 0.25% bupivacaine (10 mL h−1), 0.2% ropivacaine (10 mL h−1) alone or in combination in patients who had undergone major urological surgery. This prospective, randomized, double-blinded study investigated the efficacy of thoracic epidural infusions after major urological surgery.

Methods Patients received a 72-h continuous infusion␣(10 mL h−1) of 0.25% bupivacaine (B), 0.2% ropivacaine (R), 0.25% bupivacaine with 0.5 μg mL−1 sufentanil (BS), 0.2% ropivacaine with 0.5 μg mL−1 sufentanil (RS) or 0.5 μg mL−1 sufentanil only (S). The analysis included 109 patients.

Results The mean visual analogue scale (VAS) scores for pain were highest in the groups R and S (P < 0.001). The PaCO2 values were significantly higher in the groups RS and S (P = 0.003). Motor block occurred more frequently in the groups B and BS than in the other groups (P < 0.001). Sedation, nausea and pruritus were more common in the groups that received sufentanil.

Conclusions A continuous, epidural infusion with these drugs was safe and effective in our patients. The combination of 0.2% ropivacaine plus sufentanil appeared preferable because of the low incidence of motor block.

A study was conducted on 100 middle-aged to elderly patients (n=52, healthy; n=48, suffering from either diabetes, hypertension, ischaemic heart disease or combination of these diseases) undergoing cataract extraction to assess the effects of laryngoscopy and tracheal intubation, anaesthesia and surgery, eye bandaging and tracheal extubation, saline (control), magnesium sulphate 40 mg kg−1, esmolol 4.0 mg kg−1, lignocaine 1.5 mg kg−1 and glyceryl trinitrate 7.5 μg kg−1 given i.v. at induction of anaesthesia on heart rate (HR), blood pressure (BP), rate-pressure product (RPP) and pressure-rate quotient (PRQ). Anaesthesia was standardized. Haemodynamic responses and requirements for atropine, ephedrine and labetalol to maintain HR and BP during surgery were similar inhealthy and diseased patients, and in the test drug groups. Differences produced by the test drugs were evident until 5 min following intubation. Esmolol prevented rises in HR and RPP. Glyceryl trinitrate prevented a rise in BP, but was associated with tachycardia and a fall in PRQ to < 1.0. Magnesium sulphate and lignocaine did not prevent responses to laryngoscopy and tracheal intubation, and were associated with rises in RPP. Application of the eye dressing and tracheal extubation at the end of surgery each caused significant increases in HR, BP and RPP in all groups.

This case report describes the clinical course of a patient who inadvertently received a massive intrathecal cefazoline overdose through a lumbar drain, which had been placed after trans-sphenoidal surgery for a pituitary adenoma. She received high-dose barbiturate therapy and was monitored with electroencephalography (EEG), somatosensory evoked potentials (SSEP), brainstem auditory evoked potentials (BAEP) and transcranial Doppler ultrasound (TCD). No cerebrospinal fluid (CSF) exchange was performed, but CSF was drained continuously with daily CSF-cefazoline level monitoring. Despite the extremely toxic dose, the patient soon recovered completely.

Summary

Background and objective: The modified Airway Management Device (AMD) and the Proseal laryngeal mask airway (PLMA) are both supraglottic airway devices designed to maintain airway patency and allow ventilation during anaesthesia. In this prospective, randomized trial, we compared the two devices in patients undergoing major gynaecological procedures. Methods: Eighty-two patients undergoing elective gynaecological surgery were randomized to two groups. Group A (n = 41) had the AMD and Group P (n = 41) the PLMA inserted after induction of anaesthesia. We compared the success of airway placement, time to achieve an airway, oropharyngeal leak pressure and complications associated during anaesthesia. Results: There were no differences in patient characteristic profile for both groups. First time insertion success rates were significantly higher in Group P than in Group A (100% vs. 83%, P < 0.012). Time taken to achieve airway was also significantly shorter in Group P than in Group A (mean 21.9 ± 7.8 s vs. 40.2 ± 48.0 s, P < 0.001). The oropharyngeal leak pressure was significantly higher for Group P than Group A (mean 31.2 ± 5.7 cmH2O vs. 24.2 ± 8.3 cmH2O, P < 0.001). Ten patients in Group A had transient loss of airway during anaesthesia and needed manipulation of the airway device and four patients needed to have the airway switched to PLMA for the rest of the procedure. Conclusions: The modified AMD has a significant lower first time successful placement rate, required a longer insertion time and has a lower oropharyngeal leak pressure than the PLMA. It also demonstrated an increased loss of airway during anaesthesia. The modified AMD needs further evaluation on its efficacy and safety before its further use can be recommended.

In order to assess if a mixture of phenylephrine/lignocaine is as effective as cocaine for local analgesia and vasoconstriction during nasal fibreoptic intubation, 99 patients receiving topical nasal analgesia either with cocaine 10% or a mixture of phenylephrine 1% and lignocaine 4% were studied in a randomized double-blind investigation. After topical analgesia a flexible fibreoptic endoscope was advanced through a nostril. Larynx, glottis and trachea were endoscopically sprayed with lignocaine. Following induction of anaesthesia a nasotracheal tube was inserted fibreoptically. Pain intensity and amount of epistaxis during endoscopy were assessed.Blood pressure, heart rate and ECG-ST segment were determined before and after topical nasal analgesia, after induction of anaesthesia and after nasotracheal intubation. There were no significant differences in painintensity or epistaxis between groups during endoscopy, nor significant alterations in haemodynamic parameters or ST-segment. It is concluded that the mixture of phenylephrine and lignocaine is a useful alternative to cocaine for local analgesia and vasoconstriction during nasal fibreoptic intubation.

Alpha-adrenergic agonists produce pain relief through an opioid independent mechanism and may be alternatives to opioids for combination with local anaesthetics for analgesia during labour. We studied 41 pregnant women. Epidural block was performed with 75 μg clonidine (n=20) or 50 μg fentanyl (n=21) combined with 0.125% bupivacaine (10 mL). Maternal vital parameters were measured. Analgesia was evaluated using a visual analogue scale (VAS); sedation was scored using a five-point scale. There were no differences in maternal vital parameters, fetal heart rate (FHR) or Apgar scores between the groups. Analgesia lasted longer in the bupivacaine-clonidine group (139.4±31 min) compared with the bupivacaine–fentanyl group (127.9±48 min) (P=0.42). Additional analgesic requirement was more often in the fentany–bupivacaine group and total bupivacaine requirement was less in the clonidine–bupivacaine group (22.5±12.5mg vs. 30.9±12.8 mg) (P=0.04). This small study confirms that this combination of bupivacaine and clonidine provides satisfactory analgesia for first-stage labour, and of longer duration than bupivacaine–fentanyl.

The effects of different anaesthetics on the neutrophil oxidative response in vitro are compared. Neutrophils were stimulated with small amounts of the bacterial peptide N-formyl-L-methionyl-L-leucyl-phenylalanine as a physiological, receptor-dependent stimulus. A new flow cytometry-based method capable of detecting the small amounts of H2O2 generated by neutrophils in a heterogenous all-or-none response following submaximal stimulation with N-formyl-L-methionyl-L-leucyl-phenylalanine was used. Propofol and thiopentone suppressed the respiratory burst significantly (P < 0.05 and P < 0.01) in therapeutic concentrations, while midazolam and methohexitone inhibited significantly (P < 0.01) only at concentrations greater than the therapeutic range. Impairment of the neutrophil response was primarily because of a reduction in the number of neutrophils participating in the respiratory burst and not of a proportional decrease of the fluorescence of all neutrophils.

Abnormalities of platelet haemostasis pose increased risk to patients undergoing anaesthesia and surgery. We have investigated the effect of propofol on platelet aggregation in 12 patients undergoing upper and lower abdominal surgery. Propofol 2.5 mg kg−1 was administered via a cannula in the antecubital vein. Venous blood samples were obtained before induction and 10 min after administration of propofol. Platelet aggregation measurements were made for adenosine diphosphate (ADP), collagen and adrenaline. The results show that propofol does not affect platelet aggregation in the concentrations used.

Summary

Background and objective: Although lidocaine has been used extensively for spinal anaesthesia since 1949, it has been associated with transient neurological symptoms only in the past 10 yr. It has been suggested that early ambulation after spinal anaesthesia, as opposed to traditional 24 h recumbency, might be the causative factor for the development of transient neurological symptoms. The purpose of this study was to examine the effect of early ambulation on the incidence of transient neurological symptoms after single injection spinal anaesthesia with lidocaine 2%.

Methods: Sixty patients undergoing minor surgery under spinal anaesthesia were included. All patients received lidocaine 60 mg. After the establishment of successful subarachnoid block, patients were randomly allocated to two groups of 30 patients. Patients in Group 1 were ambulated as soon as possible, whereas patients in Group 2 were kept recumbent until 6 h after subarachnoid injection. Two days after surgery patients were contacted by a blinded observer and interviewed of transient neurological symptoms using a standardized questionnaire. Patients were asked to express the intensity of pain/discomfort on a verbal rating scale from 0 (no pain) to 10 (worst pain imaginable).

Results: There was no significant difference in the incidence of transient neurological symptoms (23% vs. 27%). In all patients, symptoms resolved completely within 6–24 h. The median pain score was 5 (range 2–8) in Group 1 and 7 (range 1–8) in Group 2.

Conclusions: Under the conditions of this study, there is no correlation between the time of ambulation after spinal anaesthesia with lidocaine and the incidence of transient neurological symptoms.

We have assessed prospectively the time to readiness for surgery following axillary block (sum of block performance and latency times) in 80 patients. The brachial plexus was identified using a nerve stimulator, and anaesthetized with 45 mL of mepivacaine 1% with adrenaline 5 μgmL−1. In group 1 (single injection) the whole volume of mepivacaine was injected after locating only one of the plexus nerves. In group 2 (multiple injections) at least three plexus nerves were located, and the volume of mepivacaine was divided between them. Sensory block was assessed by a blinded observer every 10 min. Patchy analgesia was supplemented after electrolocating the unblocked nerves after 20, 30 or 40 min. The patient was pronounced ready for surgery when analgesia was present in all areas to be operated upon, which always included the three nerves to the hand. The single injection technique required less time for block performance (mean 5.5 min) than multiple injections (mean 9.5 min), P < 0.0001. However, latency of the block was longer and the requirement for supplemental nerve blocks was greater, after single injections (33 min and 57%) than after multiple injections (15.5 min and 7%, respectively), P < 0.0001. As a result, readiness for surgery was achieved faster in group 2 (25 min), than in group 1 (38.5 min), p < 0.0001. After supplementation, block effectiveness was 100% in group 1 and 98% in group 2 (NS). The frequency of adverse effects (vessel puncture or paraesthesia) was similar in both groups. No neurological sequelae were observed.We conclude that the multiple injection technique takes longer to perform than single injection, but that readiness for surgery is faster because of shorter block latency and better spread of analgesia.

Background and objective Respiratory burst is an essential component of the neutrophil's biocidal function. In vitro, sodium thiopental, isoflurane and lidocaine each inhibit neutrophil respiratory burst. The objectives of this study were (a) to determine the effect of a standard clinical induction/tracheal intubation sequence on neutrophil respiratory burst and (b) to determine the effect of intravenous lidocaine administration during induction of anaesthesia on neutrophil respiratory burst.

Methods Twenty ASA I and II patients, aged 18–60 years, undergoing elective surgery were studied. After induction of anaesthesia [fentanyl (2 μg kg−1), thiopental (4–6 mg kg−1), isoflurane (end-tidal concentration 0.5–1.5%) in nitrous oxide (66%) and oxygen], patients randomly received either lidocaine 1.5 mg kg−1 (group L) or 0.9% saline (group S) prior to tracheal intubation. Neutrophil respiratory burst was measured immediately prior to induction of anaesthesia, immediately before and 1 and 5 min after lidocaine/saline.

Results Neutrophil respiratory burst decreased significantly after induction of anaesthesia in both groups [87.4 ± 8.2% (group L) and 88.5 ± 13.4% (group S) of preinduction level (P < 0.01 both groups)]. After intravenous lidocaine (but not saline) administration, neutrophil respiratory burst returned towards preinduction levels, both before (97.1 ± 23.6%) and after (94.4 ± 16.6%) tracheal intubation.

Conclusion Induction of anaesthesia and tracheal intubation using thiopentone and isoflurane, inhibit neutrophil respiratory burst. This effect may be diminished by the administration of lidocaine.

Summary

Background and objective: To investigate the effects of intra-aortic balloon pump therapy on parameters of global and regional oxygenation in patients undergoing cardiac surgery. Methods: As part of a large surveillance study in cardiac surgery patients (n = 266) we retrospectively analyzed the course of 28 patients requiring intra-aortic balloon pump therapy. Patients were grouped according to the time point of pump insertion (during weaning from cardiopulmonary bypass: group early intra-aortic balloon pumping (n = 17); after admission to the intensive care unit: group late intra-aortic balloon pumping (n = 9). Haemodynamic and tonometric variables, arterial lactate, and use of catecholamines were measured hourly. Measurements and results: Cardiac index increased in both groups after intra-aortic balloon pump insertion (2.2 ± 0.5 baseline; 3.4 ± 0.8 L min−1 m−2 4 h later (group early intra-aortic balloon pumping); 2.8 ± 0.5 baseline, 3.6 ± L min−1 m−2 4 h later (group later intra-aortic balloon pumping), each P < 0.05), there were no differences between groups. Arterial lactate values increased in group later intra-aortic balloon pumping after pump insertion to a maximum 2 h later (8.4 ± 6.1 mmol L−1 baseline; 12.7 ± 7.4 mmol L−1, P < 0.05), and decreased continuously afterwards. The difference of arterial and gastric CO2 showed a sharp decrease after pump insertion in group later intra-aortic balloon pumping (26.4 ± 9.8 baseline; 7.0 ± 11.1 mmHg, P < 0.05). There were no differences between groups. Epinephrine doses were higher in group later intra-aortic balloon pumping (P < 0.05). Conclusions: Intra-aortic balloon pump therapy improved global and regional splanchnic oxygenation in cardiac surgery patients with low-cardiac-output syndrome. Gastro-intestinal tonometry could provide additional information concerning tissue oxygenation. Patients with later intra-aortic balloon pump insertion needed more catecholamine therapy to achieve similar haemodynamic values.