Summary

Objective: To evaluate the effect of postoperative pain control in cardiac surgical patients on morbidity, mortality and other outcome measures. Background: New approaches in pain control have been introduced over the past decade. The impact of these interventions, either alone or in combination, on perioperative outcome was evaluated in cardiac surgical patients. Methods: We searched Medline for the period of 1980 to the present using the key terms analgesics, opioid, non-steroidal anti-inflammatory drugs, cardiac surgery, regional analgesia, spinal, epidural, fast-track cardiac anaesthesia, fast-track cardiac surgery, myocardial ischaemia, myocardial infarction, postoperative care, accelerated care programmes, postoperative complications, and we examined and discussed the articles that were identified to be included in this review. Results: Pain management in cardiac surgery is becoming more important with the establishment of minimally invasive direct coronary artery bypass surgery and fast-track management of conventional cardiac surgery patients. Advances have been made in this area and encompass specific techniques, such as central neuraxial blockade or selective nerve blocks, and drugs (opioids, sedative-hypnotics and non-steroidal anti-inflammatory drugs). Ideally, these therapies provide not only patient comfort but also mitigate untoward cardiovascular responses, pulmonary responses, and other inflammatory and secondary sympathetic responses. The introduction of these newer approaches to perioperative care has reduced morbidity, but not mortality, in cardiac surgical patients. Conclusions: Understanding perioperative pathophysiology and implementation of care regimes to reduce the stress of cardiac surgery, will continue to accelerate rehabilitation associated with decreased hospitalization and increased satisfaction and safety after discharge. Reorganization of the perioperative team (anaesthesiologists, surgeons, nurses and physical therapists) will be essential to achieve successful fast-track cardiac surgical programmes. Developments and improvements of multimodal interventions within the context of ‘fast-track’ cardiac surgery programmes represents the major challenge for the medical professionals working to achieve a ‘pain and risk free’ perioperative course.

Summary

Background and objective: Ondansetron is widely used for the prophylaxis of postoperative nausea and vomiting, while haloperidol is an antiemetic that lacks recent data on efficacy and adverse effects. Methods: In this prospective, randomized, double-blinded study involving 93 females undergoing gynaecological procedures under general anaesthesia, we compared the efficacy and adverse effects of prophylactic haloperidol 1 mg intravenous and ondansetron 4 mg intravenous vs. placebo. Results: During the overall observation period (0–24 h), in the haloperidol, ondansetron and placebo groups respectively, the incidence of nausea and/or vomiting was 40.7% (11/27), 48.2% (13/27) and 55.5% (15/27), and the need of rescue antiemetics was 22.2% (6/27), 44.4% (12/27) and 40.7% (11/27), with P values >0.05 among the three groups. During the early observation period (0–2 h), in the haloperidol, ondansetron and placebo groups respectively, the incidence of nausea and/or vomiting was 13.7% (4/29), 26.6% (8/30) and 43% (13/30), and the need for rescue antiemetics was 6.8% (2/29), 26.6% (8/30) and 36.6% (11/30). Between haloperidol and placebo groups, the P value was 0.04 for nausea and/or vomiting, and was 0.01 for rescue antiemetics, in addition to lower nausea scores (P = 0.03). During the late observation period (2–24 h), no significant difference was shown among the three groups. Conclusion: The prophylactic administration of 1 mg intravenous haloperidol or 4 mg ondansetron, in female patients undergoing gynaecological surgery, did not improve the overall incidence of nausea and/or vomiting vs. placebo. However, haloperidol 1 mg proved to be an effective antiemetic in the early observation period without significant adverse effects.

Summary

Chronic pain represents a major public health problem that impacts negatively on quality-of-life issues and healthcare costs. Unrelieved acute post-traumatic and postoperative pains are risk factors in the development of chronic pain, although psychological and environmental factors are at work as well. Flagging pain (blue, yellow and red flags) helps to identify risk factors in acute pain that need attention to avoid the transition from acute postoperative pain to acute persistent and then on to chronic pain. This offers a unique opportunity for preventative medicine.

Respiratory support with high-frequency jet ventilation has been advocated during airway surgery or to improve pulmonary mechanics and gas exchange in patients with bronchopleural fistulae or pulmonary insufficiency. Despite a large body of published evidence describing its benefits as an alternative ventilatory approach in anaesthesia and intensive care medicine, its application has not gained widespread acceptance and is restricted to specialized centres. To review the literature on high-frequency jet ventilation in European and North American institutions, we performed a search in a computerized database (MEDLINE) covering the period from 1990 until the present time, describing the use of high-frequency jet ventilation in over 7000 patients. Various modes to apply high-frequency jet ventilation during airway surgery have been established, but its value in intensive care is controversial. We report our experience with combined high-frequency jet ventilation and provide guidelines for its safe application.

Background and objective: We investigated whether an increase in anaesthesia staffing to permit induction of anaesthesia before the previous case had ended (‘overlapping’) would increase overall efficiency in the operating room. Hitherto, the average duration of operating sessions was too long, thus impeding the timely commencement of physicians' ward duties.

Methods: The investigation was designed as a prospective, non-randomized, interrupted time-series analysis divided into three phases: (a) a baseline of 3.5 months, (b) a 2.5 month intervention phase, in which anaesthesia staffing was increased by one attending physician and one nurse, and (c) a further 2 months under baseline conditions. Data focussed on process management were collected from operating room staff, anaesthesia personnel and surgeons using a structured questionnaire collected daily during the entire study.

Results: Turnover time between consecutive operations decreased from 65 to 52 min per operation (95% CI: 9; 17; P = 0.0001). Operating room occupancy increased from 4:28 to 5:27 h day−1 (95% CI: 50; 68; P = 0.005). The surgeons began their work on the ward 35 min (95% CI: 30; 40) later than before the intervention and their overtime increased from 22:36 to 139:50 h.

Conclusions: The time between surgical operations decreased significantly. Increased operating room efficiency owing to overlapping induction of anaesthesia allows more intense scheduling of operations. Thus, physicians and nurses can be released to spend more time with their patients in the ward. Improving the efficiency of the operating room alone is insufficient to improve human resource management at all levels of a surgical clinic.

In industrial countries it is estimated that the incidence of out-of-hospital sudden cardiac arrest lies between 36 and 128 per 100 000 inhabitants per year. Almost 80% of patients who initially survive a cardiac arrest present with coma lasting more than 1 h. Current therapy during cardiac arrest concentrates on the external support of circulation and respiration with additional drug and electrical therapy. Therapeutic hypothermia provides a new and very effective therapy for neuroprotection in patients after cardiac arrest. It is critical that mild hypothermia has to be applied very early after the ischaemic insult to be effective, otherwise the beneficial effects would be diminished or even abrogated. There are numerous methods available for cooling patients after ischaemic states. Surface cooling devices are non-invasive and range from simple ice packs to sophisticated machines with automatic feedback control. Other non-invasive methods include drugs and cold liquid ventilation. The newer devices have cooling rates comparable to invasive catheter techniques. Invasive cooling methods include the administration of ice-cold fluids intravenously, the use of intravascular cooling catheters, body cavity lavage, extra-corporeal circuits and selective brain cooling. Most of these methods are quite invasive and are still in an experimental stage. The optimal timing and technique for the induction of hypothermia after cardiac arrest have not yet been defined, and it is currently a major topic of ongoing research. The induction of hypothermia after cardiac arrest needs to be an integral component of the initial evaluation and stabilization of the patient.

Thirty-six unpremedicated women due for gynaecological surgery were examined for time-dependent prolongation of the QT interval in the electrocardiogram (ECG) before and after induction of anaesthesia using either sevoflurane or propofol. The conventional inhalational technique to induce anaesthesia with sevoflurane. ECG recordings were taken before, 2, 5 and 10 min after drug administration. Sevoflurane significantly lengthened (P < 0.001) the heart rate corrected QT interval within 10 min from 434±5ms to 459±6ms (mean ±SEM). Already after 2 min of sevoflurane application a trend towards prolongation was visible. The critical value of 440ms in the rate-corrected QT interval was exceeded in four patients in the sevoflurane group (n=18) but in only in one patient in the propofol group (n=18). Rate-corrected QT interval prolongation caused by sevoflurane needs to be recognized early in order to prevent the critical ventricular tachycardia torsade de pointes

One may have to use a monitor of cortical suppression to maintain the optimal level of sedation and hypnosis. The bispectral index (BIS), a processed EEG parameter, which incorporates coupling along with the frequency and amplitude of EEG waveforms, has been proposed as a measure of the pharmacodynamic anaesthetic effect on the central nervous system. The numerical value of BIS varies from 0 to 100 (no cerebral activity to fully awake patient). In order to achieve the desired level of propofol sedation or hypnosis, a target concentration of propofol at the effect site or in the blood must be delivered. Alternately, one may use BIS monitoring to monitor hypnosis or sedation levels or to reflect propofol concentrations in the blood. Significant correlations between plasma propofol concentrations and BIS values (r=0.68–0.78) have been reported by many investigators. During propofol-induced sedation, BIS values may be maintained above 75 to prevent airway obstruction and hypoxia. During propofol intravenous anaesthesia, BIS values from 40 to 60 have been proposed to maintain the desired level of hypnosis, with values below 50 associated with an insignificant probability of recall. However, the major limitation of the BIS monitor (monitor of hypnosis) relates to the fact that balanced anaesthesia comprises hypnosis, areflexia and analgesia and requires the administration of hypnotic agents, muscle relaxants and analgesics to achieve the desired clinical effects. Therefore, besides using the BIS value guidelines, one may also consider the haemodynamic, autonomic and somatic responses of the patient, the anaesthetic technique and the surgical interventions before deriving definite conclusions about the overall anaesthetic state of the patient.

Summary

Objective: This retrospective study aims to describe the airway management and benefits of nasotracheal intubation over tracheostomy in 260 patients with oral cancer undergoing surgery. Methods and Results: The medical records of 260 patients undergoing surgery for oral cancer were reviewed for airway management during the perioperative period. Eighteen patients had previous surgery for oral cancer and were scheduled for flap reconstruction, recurrence or other complications. In 28 cases neck movement was restricted and decreased mouth opening was found in 50% of all patients because of a large growth or fixation of tissues of head and neck, oral cavity, pharynx or larynx by tumour, or radiation fibrosis. In 53 patients intubation was undertaken under spontaneous ventilation. In 20 cases the trachea was extubated in the immediate postoperative period. In 220 cases patients were extubated next morning in the intensive care unit. In none of the cases was elective tracheostomy under local anaesthesia performed before surgery for the maintenance of the airway for anaesthesia. Elective tracheostomies were done in 17 cases. Three patients remained intubated for 24–48 h because of a high suspicion of airway obstruction following extubation due to a large pectoralis major flap. These three patients received a tracheostomy because of increased oropharyngeal and laryngeal oedema. In three cases emergency tracheostomies were performed due to upper airway obstruction after extubation and in one case prolonged elective ventilation was required due to severe chest infection. Conclusion: Oral cancer patients have a potentially difficult airway but, if managed properly during perioperative period, morbidity and mortality can be reduced or avoided. Oral cancer patients can be managed safely without the routine use of a tracheostomy. Nasotracheal intubation is a safe alternative to tracheostomy in oral cancer patients except in some selected patients.

Summary

Background and objectives: The GlideScope® is a new video laryngoscope. The aim of our study was to assess its use compared to a Macintosh blade in airway scenarios on the Airman™ airway simulator. The scenarios were: ‘normal’ or resting state of the manikin, pharyngeal obstruction, cervical rigidity and tongue oedema. Methods: Thirty anaesthetists from the Christchurch Anaesthetic Department attempted to pass a bougie or stylet through the vocal cords of the manikin with a size 3 Macintosh blade, then the GlideScope. View at laryngoscopy, ease of ‘intubation’ and whether they thought the GlideScope would be useful in clinical practice were recorded. Results: Forty three percent (P = 0.02) found an improved view with the GlideScope in the pharyngeal obstruction scenario. In the other scenarios there was no significant difference in view. Reportage of ease of intubation showed no statistical difference in any scenarios. However, 93% of anaesthetists considered having the GlideScope would be useful if faced clinically with one or more of the studied scenarios. Conclusions: The GlideScope improved the view in one of three difficult airway situations when used by anaesthetists with no formal training in its use. No single airway device offers a solution to all scenarios, however, we consider that the GlideScope is a useful addition to the range of difficult airway devices available.

Background and objective: Unilateral paravertebral nerve blockade has been reported to produce excellent afferent nerve block, reduce the incidence of postoperative nausea and vomiting, and reduce hospital stay following inguinal hernia repair. The aim was to compare the use of bilateral paravertebral blocks to regular general anaesthesia for ventral hernia repair.

Methods: Sixty patients were prospectively allocated to receive either bilateral paravertebral nerve blockade (midazolam for block; supplemented with light intraoperative sedation if needed) or general anaesthesia for ventral hernia repair. The end-points of the study were length of hospital stay, postoperative analgesia (visual analogue scale, supplemental opioid requirement) and incidence of postoperative nausea and vomiting.

Results: The duration of hospital stay was observed to be shorter in patients handled with bilateral paravertebral nerve blockade (2.3 [SD 1.3] days) compared with patients receiving general anaesthesia (4.1 (3.0) days). Paravertebral analgesia resulted in both lower visual analogue scores and a significantly reduced need for supplemental opioid administration during the first 48 h postoperatively compared with general anaesthesia (P < 0.001). The rate of postoperative nausea and vomiting in the paravertebral nerve blockade group was only 3.3%, while 26.7% of patients in the general anaesthesia group suffered from postoperative nausea and vomiting (P < 0.05). Paravertebral nerve blockade was associated with good patient acceptance in 90% of patients.

Conclusions: Bilateral paravertebral blockade combined with light intravenous sedation was superior to general anaesthesia for ventral hernia repair. Paravertebral blockade was associated with shorter hospital stay, improved analgesia and less postoperative nausea and vomiting. It is suggested that this technique deserves more widespread use in patients undergoing ventral hernia repair.

Procalcitonin, a new innovative inflammation parameter is presently being evaluated in clinical studies. It has been shown to be increased markedly in patients with severe bacteria induced inflammation, septic shock, endotoxinaemia and multiple organ failure. In contrast, severe viral infections or inflammatory reactions of non-infectious origin as well as autoimmune or allergic disorders do not or only very moderately increase procalcitonin serum levels. Because procalcitonin is observed at significantly higher concentrations in bacterial infections, it might assist differentiation between these infections and other aetiologies of critical illnesses. Furthermore, pro-calcitonin correlates with the severity of infection and sepsis and thus could serve as a useful marker for monitoring surgical high risk patients. Procalcitonin may serve as a valid and sensitive indicator for bacterial infection with important diagnostic potential in the peri-operative period and in intensive care medicine.

Summary

The place of sub-Tenon's block in ophthalmic surgery is now established. This block was introduced into clinical practice in the early 1990s as a simple, safe and effective technique. Since then, techniques have evolved, newer cannulae have been introduced and many complications, both minor as well as major, have been reported. This review deals with the recent developments in sub-Tenon's block.

Summary

Background and objective: Our hypothesis was that stroke volume variation during mechanical ventilation of the lungs would allow accurate prediction and monitoring of changes in cardiac index in response to fluid loading in patients with severe sepsis.

Methods: This was a prospective clinical study in a university hospital. Ten mechanically ventilated patients with severe sepsis or septic shock were given fluid loading with 500 mL 10% hydroxyethylstarch 200/0.5 over 30 min. Before and after fluid loading pulmonary arterial occlusion pressure and central venous pressure were measured. Intrathoracic blood volume index, stroke volume variation and cardiac index were measured by the transpulmonary thermodilution technique. After verifying normal distribution of the data (skewness <1.0) the paired t-test was used for statistical analysis.

Results: After fluid loading stroke volume variation decreased significantly, whereas central venous pressure, pulmonary arterial occlusion pressure, intrathoracic blood volume index and cardiac index increased significantly. Changes of cardiac index in response to fluid loading were correlated to baseline values of stroke volume variation (r = 0.64, P = 0.02) and intrathoracic blood volume index (r = −0.73, P = 0.009). Changes in cardiac index were significantly correlated to percentage changes in stroke volume variation (r = −0.65, P < 0.001) and changes in intrathoracic blood volume index (r = 0.52, P = 0.002), whereas changes in cardiac index revealed no significant correlation to changes in central venous pressure (r = 0.28, P = 0.07) and changes in pulmonary arterial occlusion pressure (r = 0.29, P = 0.06).

Conclusions: Measuring stroke volume variation may be a useful way of guiding fluid therapy in ventilated patients with severe sepsis because it allows estimation of preload and prediction of cardiac index changes in response to fluid loading.