Summary

Reporting systems are becoming more widespread in healthcare. Since they may become mandatory under the pressure of insurance companies and administrative organizations, it is important to begin to go beyond a case-by-case approach and to move to a system where there is a general reflection on the best conditions of development and setting up of such systems in medicine. In this paper, we review existing reporting systems, break down their components, examine how they are constructed and propose some ideas on how to articulate them in a dynamic process in order to improve the validity of the tool as mediator of safety, quality and well-being at work.

Summary

Background and objectives: Magnesium sulphate infusion during general anaesthesia reduces anaesthetic consumption and analgesic requirements. The aim of this study was to assess the effects of postoperative magnesium infusion on duration of block, sedation and analgesic consumption after spinal anaesthesia.

Methods: Fifty ASA I–II patients were included in the randomized double blind study. Spinal anaesthesia was performed at L3–4 or L4–5 interspace with 12.5 mg 0.5% heavy bupivacaine, using a 25 G Quincke needle. Patients received a 5 mg kg−1 bolus of magnesium sulphate followed by a 500 mg h−1 infusion or saline in the same volumes for 24 h. Time to first pain, analgesic request, return of motor function, visual analogue pain and sedation scores were evaluated every 4 h during the 24 h postoperative period. The t- and U-tests were used for statistical analyses. Data were expressed as mean ± SD, with P < 0.05 being considered significant.

Results: Vital signs were stable during spinal anaesthesia and postoperative period. When compared to the control group, time to analgesic need was increased and total analgesic consumption was reduced in the magnesium group (meperidine consumption 60.0 ± 73.1 mg control group, 31.8 ± 30.7 mg magnesium group, P = 0.02).

Conclusions: Magnesium sulphate infusion may be used as an adjunct for reducing analgesic consumption after spinal anaesthesia.

Summary

Background and objective: To evaluate the efficacy of 0.1% ropivacaine with fentanyl 2 μg mL−1 via epidural for analgesia in labour.

Methods: In a randomized study, 80 nulliparous parturients in labour had epidural analgesia initiated with 0.2% ropivacaine and fentanyl and were then randomized to receive either 0.1% ropivacaine with fentanyl 2 μg mL−1 at 10 mL h−1 (Group R1, n = 38) or 0.2% ropivacaine with fentanyl 2 μg mL−1 at 8 ml h−1 (Group R2, n = 39) as epidural infusions. Supplementary analgesia was provided on request with ropivacaine 0.2% 5 mL as an epidural bolus.

Results: There were no significant differences between the visual analogue pain scores either with respect to motor block or sensory block. The amount of local anaesthetic used was lower in the 0.1% ropivacaine group than in the 0.2% ropivacaine group (P = 0.001). Side-effects, patient satisfaction, labour outcome and neonatal outcomes were similar in both groups.

Conclusions: An epidural infusion of 0.1% ropivacaine with fentanyl 2 μg mL−1 at 10 mL h−1 provided adequate analgesia in the first stage of labour. The level of analgesia was similar to that obtained using 0.2% ropivacaine with fentanyl 2 μg mL−1 and with no differences with regard to motor or sensory block.

Summary

Background and objective: In 1991 general anaesthesia was used extensively for emergency Caesarean section at Haukeland University Hospital even in patients with an ongoing epidural infusion. With increased knowledge of the potential safety benefits of regional anaesthesia and increased experience with the technique, we decided to use indwelling epidural catheters for emergency Caesarean section.

Methods: We conducted a retrospective analysis of a full annual data set on emergency Caesarean section in parturients with ongoing epidural analgesia in 1997 and compared it with a similar data set from 1991.

Results: Epidural anaesthesia was used significantly more often in 1997 with 115 (78%) cases than in 1991 with five (12%) cases (P < 0.001). Elapsed time before adequate anaesthesia and the start of surgery was significantly shorter in 1991 (mean 8.3 min) compared to 1997 (mean 13 min) (P < 0.001). No deaths or major complications were observed in either group. Intraoperative minor complications were observed more frequently in 1997 with 70 cases (47%) than in 1991 with two cases (6%) (P < 0.001). The principal complications were hypotension and nausea. Postoperative complications in mother and neonate were similar in both groups. There was a significantly shorter mean hospital stay in 1997 (6 days), compared with 1991 (8 days) (P < 0.001).

Conclusion: The increase in the use of indwelling epidural catheters for emergency Caesarean section has resulted in a significant increase in the use of regional anaesthesia. A modest increase in time elapsed before start of surgery was observed although there were no significant differences in the number of neonates with low Apgar scores. No major complications were observed, but there was an increased frequency of minor complications in 1997.

Summary

Background and objective: We conducted a prospective randomized study to evaluate whether the duration of action of a single bolus dose of rocuronium is influenced by maintenance of anaesthesia with sevoflurane, desflurane or propofol infusion.

Methods: Fifty-seven ASA I–II patients undergoing elective abdominal surgery were enrolled in this study. Anaesthesia was induced with thiopental 3–5 mg kg−1 or propofol 2.5 mg kg−1 and fentanyl 5 μg kg−1 and tracheal intubation was facilitated with rocuronium 0.9 mg kg−1. Thereafter patients were randomly allocated to three different groups to receive sevoflurane, desflurane or propofol for maintenance of anaesthesia. Recovery of neuromuscular function was monitored by single twitch stimulation of the ulnar nerve and by recording the adductor pollicis response using accelerometry. Intergroup recovery times to 5% of control value of single twitch were analysed using analysis of variance with Bonferroni correction.

Results: The mean (95% confidence interval) recovery time to 5% of control value of single twitch during desflurane anaesthesia was 90.18 (86.11–94.25) min. Significantly shorter recovery times were observed during sevoflurane or propofol anaesthesia, 58.86 (54.73–62.99) min and 51.11 (45.47–56.74) min, respectively (P < 0.001). There were also significant differences in the recovery time between groups receiving desflurane vs. sevoflurane (P < 0.001) and desflurane vs. propofol (P < 0.001).

Conclusions: Desflurane anaesthesia significantly prolongs the duration of action of rocuronium at 0.9 mg kg−1 single bolus dose, compared to sevoflurane or propofol anaesthesia maintenance regimens.

Summary

Background and objective: Remifentanil has a short duration of action and constant elimination, which allow administration of high doses, without prolonging recovery. Remifentanil has been compared to alfentanil, as part of a total intravenous anaesthetic technique, where remifentanil provided better anaesthetic conditions than alfentanil, without adverse effect on recovery. However, these results were obtained during anaesthesia involving neuromuscular blockade, which may mask both signs of insufficient anaesthesia and side-effects such as muscle rigidity. The aim of this study was to compare remifentanil with alfentanil for anaesthesia without neuromuscular blockade.

Methods: We performed a prospective, randomized, double-blind, four-centre study to compare remifentanil infusion 15 μg kg−1 h−1 and alfentanil infusion 60 μg kg−1 h−1, using a total intravenous technique for non-paralysed patients, and the laryngeal mask airway for airway management. We enrolled 192 patients, 18–65 yr of age with ASA I–II, undergoing minor surgery. The primary endpoint was the number of patients having pre-defined responses to surgical stimulation. A number of secondary criteria was evaluated to assess undesirable properties of the procedures.

Results: In the alfentanil group, 85% of patients responded to surgical stimulation, vs. 35% in the remifentanil group (P < 0.0001). No difference was found in recovery data, or in any other parameter than those related to insufficient anaesthesia.

Conclusions: The remifentanil-based technique provided significantly better anaesthetic conditions than the alfentanil-based technique in the setting of this study, without causing any significant adverse effects.

Summary

Background and objective: The use of opioids with sevoflurane for induction of anaesthesia is associated with fewer reactions to laryngoscopy but increases the risk of apnoea. Thus it is important to search for the optimal opioid dose. The aim of this study was to compare two sufentanil doses during induction with sevoflurane in young adults.

Methods: Sixty-three young patients (18–26 yr) undergoing wisdom-tooth extraction were randomly allocated to one of the two sufentanil dose groups: 0.15 μg kg−1 (n = 33) or 0.30 μg kg−1 (n = 30). Sufentanil was injected 1 min before sevoflurane inhalation. Sevoflurane was inhaled using the three-breath vital-capacity technique with 8% sevoflurane and 100% oxygen. The anaesthesiologist decided when to intubate the trachea. The length of time for intubation was measured. In addition, any apnoea, patient movement, adequacy of the laryngoscopic view, coughing and haemodynamic responses were recorded.

Results: Mean time to intubate the trachea, full laryngoscopy view and open-cord position were similar in both groups. The incidence of apnoea was higher in Group 0.30 (P < 0.05). The incidence of patient movement (P < 0.05) and coughing (P < 0.001) was lower in Group 0.30 than in Group 0.15. Sufentanil 0.30 μg kg−1 attenuated the change in heart rate more effectively than sufentanil 0.15 μg kg−1. Mean arterial pressure was similar and stable in both groups during induction of anaesthesia.

Conclusions: In current clinical practice during sevoflurane induction, sufentanil 0.30 μg kg−1 provided a better quality of induction than sufentanil 0.15 μg kg−1, without significant cardiovascular depression, although the risk of apnoea is increased.

Summary

Background and objective: The effects of desflurane and sevoflurane on the failing myocardium are still uncertain. We investigated the effects of different concentrations of sevoflurane, desflurane and halothane in dogs with pacing induced chronic heart failure.

Methods: Global (left ventricular pressure, left ventricular dP/dt, Konigsbergtransducer) and regional myocardial function (systolic segment length shortening, ultrasonic crystals) were measured in chronically instrumented dogs with tachycardia induced severe congestive heart failure. Measurements were performed in healthy dogs and after induction of heart failure in the awake state and during anaesthesia with 0.75, 1.0, 1.25 and 1.75 minimum alveolar concentration (MAC) of halothane, sevoflurane or desflurane.

Results: The anaesthetics reduced dP/dtmax in a dose-dependent manner in healthy dogs (dP/dtmax decreased to 43–53% of awake values at 1.75 MAC). Chronic rapid left ventricular pacing increased heart rate and left ventricular end-diastolic pressure and decreased mean arterial pressure, left ventricular systolic pressure and dP/dtmax. The reduction in contractility was similar in the failing myocardium (to 41–50% of awake values at 1.75 MAC). Segmental shortening was reduced during anaesthesia by 50–62% after pacing compared with 22–44% in normal hearts. While there were similar effects of the different anaesthetics on diastolic function in healthy dogs, after induction of heart failure a more pronounced increase of the time constant of isovolumic relaxation and a greater decrease of dP/dtmin was observed with sevoflurane than with desflurane, indicating a stronger depression of diastolic function.

Conclusions: While the negative inotropic effects of sevoflurane and desflurane were similar in normal and in the failing myocardium in vivo, desflurane led to a better preservation of diastolic function in the failing myocardium.

Summary

Background and objective: To investigate and compare the performance of bispectral index (BIS) and auditory evoked response index (AAI) in detecting the transition from consciousness to unconsciousness during anaesthesia induction by propofol, alone and in combination with fentanyl.

Methods: Anaesthesia was induced with either an intravenous infusion of 30 mg kg−1 h−1 of propofol plus 2 μg kg−1 of fentanyl (Group PF, n = 20) or an intravenous infusion of 30 mg kg−1 h−1 of propofol plus normal saline (Group P, n = 20). BIS, AAI and the doses of propofol administered were recorded at the end-point of unresponsiveness to verbal commands. The propofol plasma concentration was also measured.

Results: The propofol dose and plasma propofol concentration required to achieve loss of consciousness were significantly lower in patients pretreated with fentanyl (P < 0.001). The mean BIS value at loss of consciousness was significantly different between the two groups (74.10 in Group PF vs. 60.80 in Group P) (P < 0.001). However, no difference in the AAI was seen between the two groups at loss of consciousness (32.90 in Group PF vs. 31.80 in Group P) (P > 0.05). In both groups, the regression analysis values (r-values) between BIS and plasma propofol concentrations at the onset of unconsciousness were higher than those between AAI and propofol concentrations (0.553 vs. 0.180 in Group P; 0.432 vs. 0.308 in Group PF).

Conclusions: These results show that a fentanyl bolus is effective in augmenting the hypnotic effect of propofol during anaesthesia induction. AAI appears to be able to measure the transition from consciousness to unconsciousness at similar values, regardless of whether or not fentanyl pretreatment is used whereas the BIS values were not independent of fentanyl pretreatment. This suggests that AAI may be a better indicator of conscious status during propofol/fentanyl anaesthesia, where it appears to be independent of the anaesthesia regimen.

Summary

Background and objective: This study was undertaken to investigate the role played by antidiuretic hormone (ADH), the renin–angiotensin system and atrial natriuretic factor (ANF) in the oliguria in patients undergoing spinal fusion.

Methods: Sixteen patients undergoing posterior spinal fusion using isoflurane and fentanyl (n = 8) or sufentanil (n = 8) had renin, aldosterone, ADH and ANF measurements.

Results: Compared to the non-oliguric patients, the oliguric patients had a higher number of fused vertebrae 10.5 ± 1.3 vs. 9.0 ± 0.5 (P = 0.01) and higher renin values at 12 h (3.3 ± 3.2 vs. 0.7 ± 0.6 ng L−1 s−1, P = 0.04). Hormonal values that had a significant correlation with intraoperative diuresis were: renin at 0.5 h (r2 = 0.26, P = 0.04), aldosterone at 0.5 h (r2 = 0.30, P = 0.03) and ANF at 0.5 h (r2 = 0.32, P = 0.02). Those that had a significant correlation with the mean postoperative diuresis were: renin at 6 h (r2 = 0.29, P = 0.03), 8 h (r2 = 0.26, P = 0.04) and 12 h (r2 = 0.31, P = 0.03), aldosterone at 6 h (r2 = 0.54, P = 0.001), 8 h (r2 = 0.40, P = 0.01) and 12 h (r2 = 0.32, P = 0.03), ADH at 24 h (r2 = 0.38, P = 0.01) and ANF at 6 h (r2 = 0.26, P = 0.045). Using stepwise regression, excluding hormonal values, only two continuous variables had a significant correlation with the mean postoperative diuresis: the number of fused vertebrae (P = 0.02) and the length of surgery (P = 0.02).

Conclusion: Activation of the renin–angiotensin system is the major cause of the early intraoperative oliguria. ADH and the renin–angiotensin system are both involved in the pathophysiology of postoperative oliguria in patients undergoing spinal fusion.

Summary

Background and objective: Minimizing cervical vertebrae motion during endotracheal intubation is important in patients with cervical instability. The aim of this study was to compare upper cervical spine extension during endotracheal intubation using three different techniques.

Methods: Duration of intubation and movement of upper cervical vertebrae during endotracheal intubation were compared in 33 patients undergoing lumbar laminectomy. Patients requiring tracheal intubation under general anaesthesia and neuromuscular blockade were randomly allocated into three groups – direct laryngoscopy, intubating laryngeal mask (LM) airway and fibreoptic laryngoscopy. The procedure was recorded by video-fluoroscopy and analysed with computer-assisted measurements. The maximum movement of the C1/C2 and C2/C3 vertebrae during intubation were obtained. Data were analysed using one-way analysis of variance with Bonferroni and Kruskal–Wallis tests.

Results: We found statistically significant movement between the first and second, but not between the second and third cervical vertebrae. The mean (±SD) movement at C1/C2 was 10.2 ± 7.3° with direct laryngoscopy, 5.0 ± 6.3° with LM and 1.6 ± 3.2° with fibreoptic laryngoscopy. This difference was statistically significant (P = 0.01) between the direct and fibreoptic laryngoscopy groups. The maximum movement at C2/C3 was 2.2 ± 10.1° with direct laryngoscopy, 3.5 ± 5.1° with LM and 0.5 ± 3.2° with fibreoptic laryngoscopy. Duration of intubation was significantly longer in the intubating LM group (P < 0.001).

Conclusion: We conclude that fibreoptic laryngoscopy is the more suitable intubation technique when cervical spine movement is not desired.

Summary

Background and objectives: Teaching is an important responsibility of non-consultant hospital doctors. In Ireland, specialist registrars (SpRs) in anaesthesia are contractually obliged to teach medical students, other doctors and nurses. Both medical students and fellow non-consultant hospital doctors attribute between 30 and 40% of their knowledge gain to non-consultant hospital doctors.

Methods: We carried out a confidential telephone survey of anaesthetic SpRs in Ireland regarding their current teaching practices and the perceptions of their role as undergraduate teachers. All the SpRs currently working in clinical practice in Ireland were eligible.

Results: Fifty-five of the 79 (70%) SpRs responded to the questionnaire. Only 7 (12.7%) of the respondents said they had been well trained as a teacher. The majority of the respondents stated that they would attend a learning-to-teach course/workshop if one was available, and felt that such a course would improve their ability as a teacher. Only 8 (14.5%) agreed that adequate emphasis is placed on commitment to teaching in the assessment of SpRs, both by individual departments and by the College of Anaesthetists. Anaesthetic SpRs in Ireland spend a considerable amount of time each day teaching undergraduate medical students, the majority (68.9%) stated that they had inadequate time to prepare for teaching.

Conclusion: The majority of the respondents stated that they enjoy teaching, feel that they play an important role in undergraduate teaching but have inadequate time to prepare for teaching. An adequate emphasis is not placed on their commitment to teaching.