Abnormal sensations evoked over the chest and persistent peri-incisional chest pain after cardiac surgery.

Risk factors for developing Persistent peri-incisional Chest Pain (PCP) after sternotomy are multiple. We examined whether hypoesthesia, hyperalgesia or dysesthesia, evoked in the postoperative period might be associated with PCP after sternotomy. One hundred patients undergoing a sternotomy were evaluated on day 5. Peri-incisional sensory testing was performed using von Frey filament. Presence and severity of PCP were assessed at 2 and 6 months. PCP was present in 29% and 15% of patients respectively at 2 and 6 months. Hyperalgesia on day 5 was present in 43% of patients with PCP at 6 months compared to 15% without PCP. Hypoesthesia was present in 57% of patients with PCP at 6 months compared to 22% without PCP. There was no significant difference in the incidence of dysesthesia. On day 5, hyperalgesia was correlated with a risk to develop PCP at 6 months. Among sensory abnormalities, the presence of hyperalgesia is associated with PCP at 6 months postoperatively.

Guidelines for the use of fresh frozen plasma.

Recommendations, which aim at standardising and rationalising clinical indications for the transfusion of fresh frozen plasma (FFP) in Belgium, were drawn up by a working group of the Superior Health Council. For this purpose the Superior Health Council organised an expert meeting devoted to "Transfusion Guidelines: Pathogen reduction, products and indications for the transfusion of plasma" in collaboration with the Belgian Haematological Society.The experts discussed the indications for the transfusion of FFP, pathogen reduction for FFP and the practical issues of administering FFP and plasma-derived concentrates. The recommendations formulated by the experts were validated by the working group with the purpose of harmonising FFP transfusion in Belgian hospitals.

Guidelines for the transfusion of red cells.

The following recommendations, which aim at standardising and rationalising clinical indications for the transfusion of red cells in Belgium, were drawn up by a working group of the Superior Health Council. To this end, the Superior Health Council organised an expert meeting devoted to "Guidelines for the transfusion of red cells" in collaboration with the Belgian Hematological Society. The experts discussed the indications for red cell transfusions, the ideal red cell concentrate, the practical issues of administering red cells, and red cell transfusions in patients in a critical condition. The recommendations formulated by the experts were validated by the working group with the purpose of harmonising red cell transfusion in Belgian hospitals.

Cystatin C in cardiac surgery.

Cystatin C has recently been proposed as an alternative marker of glomerular filtration rate. The study compares cystatin C and creatinine concentrations during cardiopulmonary bypass and the first 72 hours postoperatively in patients undergoing coronary artery bypass graft. Forty-nine patients with normal preoperative renal and cardiac function were scheduled for coronary artery bypass graft. Blood was sampled for creatinine and cystatin C measurements at 7 time points till 72 hours postoperatively. Glomerular filtration rate was estimated from calculated clearance using the Cockroft and Gault formula for creatinine and Larsson equation for cystatin C. The baseline values of both markers were within the normal range. Their concentrations were comparable during the whole study period. This was also the case for the calculated creatinine and cystatin C clearance. In patients with normal preoperative renal function undergoing coronary artery bypass graft, measured creatinine concentration remains a cheap and easy way of estimating renal function.

Occupational stress and burnout in anaesthesia.

BACKGROUND: Formal studies on stress in anaesthetists have usually measured stress through mental or physiological indicators. When using this approach, one must be careful not to confuse the effects of stress or outcome variables and the sources of stress or antecedent variables. To date, it seems from the literature that there is no clear evidence of a common pattern of physiological effects of stress for all the sources of stress. Furthermore, work characteristics such as job satisfaction, job control and job support may moderate the effects of stress. METHODS: We measured the effects of stress together with the sources of stress and job characteristics, using self-reported questionnaires rather than physiological indicators in order to better diagnose stress in anaesthetists. RESULTS: The mean stress level in anaesthetists was 50.6 which is no higher than we found in other working populations. The three main sources of stress reported were a lack of control over time management, work planning and risks. Anaesthetists reported high empowerment, high work commitment, high job challenge and high satisfaction. However, 40.4% of the group were suffering from high emotional exhaustion (burnout); the highest rate was in young trainees under 30 years of age. CONCLUSIONS: Remedial actions are discussed at the end of the paper.

Application of tRNA intergenic spacer PCR for identification of Enterococcus species.

tRNA intergenic spacer PCR (tDNA-PCR) was evaluated for its usefulness in the differentiation of enterococcal species of human and animal origin. This technique was carried out for 124 strains belonging to 17 enterococcal species and generated DNA fragments, which were separated by capillary electrophoresis. tDNA-PCR enabled us to discriminate for all species tested. Enterococcus faecium showed minor but reproducible differences with Enterococcus durans, while Enterococcus hirae was easily distinguishable. Enterococcus avium, Enterococcus malodoratus, and Enterococcus raffinosus generated highly similar though distinctive patterns.

Current anesthesia manpower in Belgium in relation to anesthesia work locations.

Two inquiries were conducted in 1995 and 1996 involving all anesthesiology departments in Belgium. The response rate was 57%. One aim of these surveys was to estimate the anesthesia manpower and the number of anesthesia work locations in each hospital, by hospital size and by region. In the operating theater, between 0.77 and 2.24 physicians (full time equivalents) were available per operating room. When considering also anesthesia in remote locations outside the operating theater, and the availability of fully trained physicians and trainees (efficiency estimated as 75% of a fully trained specialist), the ratio decreases to between 0.48 and 1.25, the highest ratios being found in larger hospitals (> 650 beds). When physicians currently in anesthesiology training will have graduated the mean availability of anesthesiologists per anesthesia work station will be 0.87 in Belgium, vs 0.52 in 1996.

Can we predict the future evolution of anesthesiology workforce in Belgium?

Two models are proposed to predict the evolution of anesthesiology workforce over the next 20 years. Each model features various scenarios according to different assumptions related to future numbers of female anesthetists, working hours, or regulations for postgraduates' working for conditions. However the main uncertainties derive from the unknown evolution of demands. Despite their differences both models agree on several important conclusions: a 13 to 14% shortage of anesthesiologists currently exists to satisfy O.R. demands, this shortage will decrease over the next ten years, and after 2010 a new shortage could arise under the combined pressure of the numerus clausus, of the number of female anesthesiologists and of the aging of the still young population of anesthesiologists.

Blood transfusion practice in Belgium. As assessed by a national survey.

In April 1995 the Ministry of Public Health invited all Belgian hospitals to participate to a survey on the use of blood transfusion. The questionnaire presented two parts, the first one devoted to products transfused and the second one to the transfusion organisation in the hospital. 71 hospitals answered: 7 university and 64 general hospitals. All hospitals reported the use of red cells, 31 of them still used whole blood. Surgical departments transfused the greatest absolute amount of units, but the highest intensity (units/bed/year) was observed in intensive care units. 52 hospitals mentioned the use of autologous predeposit. The highest consumption of platelets occurred in medicine but intensive care showed the highest intensity of platelet transfusion. In 41 hospitals platelets were obtained by cytapheresis. The number of plasma units transfused was highly correlated with the quantities of packed red cells and whole blood transfused. Ten hospitals didn't report the use of any blood conservation technique. Returning unused units to the blood bank was allowed in 80% of the hospitals, their return to the transfusion center was permitted in 65% of the hospitals. A transfusion committee existed in only 11 hospitals. Transfusion should be improved by a better education of all physicians and nurses involved with transfusion and by improving standardisation, by better documentation, better reporting and information of all health care workers involved.

Clinical evaluation of Duraflo II heparin treated extracorporeal circulation circuits (2nd version). The European Working Group on heparin coated extracorporeal circulation circuits.

OBJECTIVES: To evaluate whether the application of heparin treated circuits for elective coronary artery surgery improves postoperative recovery, a European multicenter randomised clinical trial was carried out. METHODS: In 11 European heart centers, 805 low-risk patients underwent cardiopulmonary bypass (CPB) with either an untreated circuit (n = 407) or an identical but heparin treated circuit (n = 398, Duraflo II). RESULTS: Significant differences were found among participating centers with respect to patient characteristics, blood handling procedures and postoperative care. The use of heparin treated circuits revealed no overall changes in blood loss, blood use, time on ventilator, occurrence of adverse events, morbidity, mortality, and intensive care stay. These results did not change after adjustment for centers and (other) prognostic factors as analysed with logistic regression. In both groups no clinical or technical (patient or device related) side effects were reported. Because female gender and aortic cross clamp time appeared as prognostic factors in the logistic regression analysis, a subgroup analysis with these variables was performed. In a subpopulation of females (n = 99), those receiving heparin treated circuits needed less blood products, had a lower incidence of rhythm disturbances and were extubated earlier than controls. In another subgroup of patients with aortic cross clamp time exceeding 60 min (n = 197), the amount of patients requiring prolonged intensive care treatment (> 24 h) was significantly lower when they received heparin treated circuits versus controls. CONCLUSION: These findings suggest that improved recovery can be expected with heparin treated circuits in specific higher risk patient populations (e.g. females) and when prolonged aortic cross clamp time is anticipated. Further investigations are recommended to analyses the clinical benefit of heparin treated circuits in studies with patients in different well defined risk categories and under better standardised circumstances.

Nasal continuous positive airway pressure in the perioperative management of patients with obstructive sleep apnea submitted to surgery.

Anesthetic, sedative, and analgesic drugs have been shown in animals and humans to selectively impair upper airway muscle activity. In patients with an already compromised upper airway, these drugs may further jeopardize upper airway patency, especially during sleep. Thus, patients with obstructive sleep apnea syndrome (OSAS) are at high risk for surgery because of the use of the aforementioned drugs in the perioperative period. It has been recommended that such drugs should be avoided or used with extreme caution in patients with OSAS submitted to surgery. We report herein on 16 adult patients with documented OSAS undergoing various types of surgical procedures, including coronary artery bypass surgery. Anesthesia was carried on with the usual type of drugs for each type of surgery. Postoperative opioid analgesia and sedation were not restricted. The first patient, whose OSAS was diagnosed but not treated, died after various complications, including a respiratory arrest in the ward. The second patient experienced serious postoperative complications until a treatment for OSAS with nasal continuous positive airway pressure (N-CPAP) was instituted, and thereafter he made an uneventful recovery. The 14 following patients were started on N-CPAP before surgery, were put on N-CPAP as soon as extubated, on a near-continuous basis, for 24 to 48 h and thereafter for all sleep periods. None of them had major complications. The intensive care unit and hospital stays were the normal ones for each type of surgery in our institution. We conclude that N-CPAP started before surgery and resumed immediately after extubation allowed us to safely manage a variety of surgical procedures in patients with OSAS, and to freely use sedative, analgesic, and anesthetic drugs without major complications. Every effort should be made to identify patients with OSAS and institute N-CPAP therapy before surgery.

The use of somatosensory evoked potentials to determine the optimal degree of hypothermia during circulatory arrest.

We sequentially recorded subcortical (P14) and cortical (N20) somatosensory evoked potentials (SEPs) in 32 patients undergoing deep hypothermic circulatory arrest (CA). Under normal hemodynamic conditions, hypothermia initially produced N20 disappearance at a mean nasopharyngeal temperature of 20.4 +/- 2.6 degrees C (range 14.5 to 26.1 degrees C) and P14 disappearance at a mean of 16.9 +/- 2.0 degrees C (range 12.4 to 20.2 degrees C). On rewarming, P14 reappeared at mean temperature of 19.3 +/- 4.0 degrees C (range 13.5 to 29.2 degrees C) and N20 at a mean of 21.1 +/- 4.1 degrees C (range 14.3 to 29.6 degrees C). The delay of SEP reappearance after restoration of blood flow correlated significantly with CA duration (r = 0.74 for P14, and r = 0.62 for N20; p < 0.01). Neurological recovery was uneventful in 23 patients; 5 patients presented with neurological sequelae (minor or transient in 4; no recovery from anesthesia and death after 48 hours in 1), and 4 patients died during operation. Twenty-three of 24 surviving patients in whom P14 disappearance was the criterion that hypothermia was deep enough to perform CA (duration: 17 to 94 min) had a normal neurological outcome. By contrast, all surviving patients in whom cortical SEPs disappeared at higher temperatures presented neurological sequelae. In conclusion, the neurophysiological monitoring of brain stem activity, as specifically provided by SEPs, enables determination of the optimal temperature for CA, and demonstrates superiority of SEP monitoring over the use of EEG.