To determine the efficacy and safety of intravenous postoperative morphine titration in the elderly compared with younger patients.

In the post-anaesthesia care unit, patients complaining of pain received morphine until adequate pain relief. Intravenous morphine was titrated as 3 mg boluses in young (age ⩽65 yr) and 2 mg in elderly patients (>65 yr) every 5 min.

We studied 350 young and 68 elderly patients. There were no significant differences between the two age groups for pain intensity at the onset of titration (numerical rating scale, 7.4 ± 1.7 in young vs. 7.5 ± 1.7 in elderly patients), area under the curve of numerical rating scale vs. morphine boluses (97.7 ± 59.6 vs. 98.2 ± 62), number of boluses required to obtain pain relief (3 ± 1.3 vs. 3 ± 1.3), percentage of titration failures (10% vs. 9%) and incidence of excessive sedation (18% vs. 21%). Renal clearance was significantly reduced in elderly compared with young patients (55 ± 21 vs. 85 ± 15 mL min−1; P < 0.0001).

Using lower bolus doses, pain relief in the immediate postoperative period with morphine was as efficacious and safe in elderly patients as in younger patients. The decrease in renal clearance of morphine in the elderly justifies the reduction of intravenous morphine boluses for the treatment of postoperative pain.

Post-anaesthetic shivering is one of the most common complications, occurring in 5–65% of patients recovering from general anaesthesia and 33% of patients receiving epidural anaesthesia. Our objective was to investigate the efficacy of intraoperative dexmedetomidine infusion on postoperative shivering.

Ninety female patients, ASA I-II, 35–60 yr old, scheduled for elective total abdominal hysterectomy with or without bilateral salpingo-oophorectomy were randomized into two groups. After endotracheal intubation one group received normal saline infusion and the other received dexmedetomidine as a loading dose of 1 μg kg−1 for 10 min followed by a maintenance infusion of 0.4 μg kg−1 h−1. In the recovery room, pain was assessed using a 100 mm visual analogue scale and those patients who had a pain score of more than 40 mm were administered 1 mg kg−1 intramuscular diclofenac sodium. Patients with shivering grades more than 2 were administered 25 mg intravenous meperidine. Patients were protected with passive insulation covers.

Post-anaesthetic shivering was observed in 21 patients in the saline group and in seven patients in the dexmedetomidine group (P = 0.001). Shivering occurred more often in the saline group. The Ramsay Sedation Scores were higher in the dexmedetomidine group during the first postoperative hour. Pain scores were higher in the saline group for 30 min after the operation. The need for intraoperative atropine was higher in the dexmedetomidine group. Intraoperative fentanyl use was higher in the saline group. Perioperative tympanic temperatures were not different between the groups whereas postoperative measurements were lower in the dexmedetomidine group (P < 0.05).

Intraoperative dexmedetomidine infusion may be effective in the prevention of post-anaesthetic shivering.

Patent blue (4-[(4-diethylaminophenyl)-(4-diethylazaniumylidencyclohexa-2,5-dienyliden) methyl]-6-hydroxy-3-sulfo-benzolsulfonate, sodium salt) is a contrast dye used for the intraoperative detection of the primary lymphatic nodes draining the area of tumour infiltration. The dye is known to interact with pulse oximeter readings. However, the degree of alteration seems to be moderate and predictable when patent blue is injected into the perimammilar region during breast surgery.

Here we report severe interference with the anaesthetic monitoring when patent blue was injected into the cervix prior to laparoscopy-assisted radical vaginal hysterectomy for cervical cancer.

Injection of patent blue into the cervix induced a rapid (within 14 ± 9 min after the injection) and severe (from ⩾98% to 89 ± 2%) decrease in pulse oximeter readings, accompanied by positive methaemoglobin values of 7.3 ± 2.5% (arterial co-oximetry, Bayer Rapidlab 865 blood gas analyser; Bayer, Fernwald, Germany). Control of these values by a different device (Radiometer ABL co-oximeter blood gas analyser; Radiometer, Willich, Germany) yielded negative methaemoglobin results (<1.7%, mean 0.9 ± 0.6%). The arterial PO2 was normal in all patients throughout the procedure.

Injection of patent blue into the cervix uteri interferes dramatically with pulse oximeter readings. This situation is further complicated by device-dependent arterial co-oximetry methaemoglobin results. For the time being it is recommendable to monitor adequate oxygenation of the patient in the presence of patent blue by regular control of the arterial PO2. Clearly, the unresolved issue of reliable methaemoglobin determination in the presence of patent blue remains a matter of clinical concern for anaesthetists.

Controlled hypotension is frequently used for obtaining better exposure during tympanoplasty. The aim of this study was to compare dexmedetomidine, a selective, short-acting, central α2-adrenergic agonist with remifentanil, an ultra-short-acting opioid with properties similar to other μ-specific agonists, regarding their effects in achieving controlled hypotension and improving surgical field exposure and surgeon’s satisfaction during tympanoplasty.

In this prospective, double-blind pilot study, 24 consecutive patients scheduled for elective tympanoplasty were randomly assigned to receive either dexmedetomidine 1 μg kg−1 over 10 min at anaesthesia induction followed by 0.4–0.8 μg kg−1 h−1 infusion during maintenance or remifentanil 1 μg kg−1 over 1 min at anaesthesia induction followed by 0.2–0.4 μg kg−1 min−1 infusion during maintenance. Mean arterial pressure and heart rate were recorded before induction, at incision, 30, 60, 90 and 120 min after incision and 10 min after stopping the infusion. Surgical field exposure condition and satisfaction scores were assessed by the surgeon, blinded to the study drugs.

Mean arterial pressure and heart rate were significantly lower in the remifentanil group compared with the dexmedetomidine group at all times (P = 0.03 and 0.036, respectively). Surgical field exposure condition (3 ± 0.01 vs. 2.3 ± 0.7; P = 0.039) and surgeons’ satisfaction (3 ± 0.01 vs. 2.25 ± 0.87; P = 0.039) scores were significant after remifentanil compared with dexmedetomidine.

Infusion of dexmedetomidine, at the doses used in this study, was less effective than remifentanil in achieving controlled hypotension, good surgical field exposure condition and surgeons’ satisfaction during tympanoplasty.

The aim of this study was to compare the postoperative analgesic efficacy of intraperitoneal tramadol with intravenous tramadol or normal saline in patients undergoing laparoscopic cholecystectomy.

Sixty-one patients undergoing laparoscopic cholecystectomy were randomized to one of three groups in a double-blind manner via coded syringes. All patients received an intravenous and an intraperitoneal injection after installation of the pneumoperitoneum and again before removal of the trocars. In the control group, all injections were with normal saline. In the intravenous tramadol group, patients received intravenous tramadol 100 mg and intraperitoneal saline. In the intraperitoneal tramadol group, patients received intravenous saline and intraperitoneal tramadol 100 mg. All patients had a standard anaesthetic. Postoperative analgesia was with morphine. Postoperatively, numeric pain scores for parietal and visceral pain, 1 h and 24 h morphine consumption, and adverse effects were recorded.

Parietal and visceral pain scores were lowest in the intravenous tramadol group during the first postoperative hour (P < 0.016 compared with control). The delay until the first analgesic administration was longest in the intravenous tramadol group (median 23 min, range 1–45), when compared with the intraperitoneal tramadol group (10, 1–120 min, P = 0.263) or with the control group (1, 1–30 min, P = 0.015). One-hour morphine consumption was significantly lower in the intravenous tramadol group (mean ± SD; 3.4 mg ± 2.5) and in the intraperitoneal tramadol group (4.4 ± 4.3 mg) compared with the control group (6 ± 2 mg) (P = 0.044). There was no difference between the three groups regarding pain scores, morphine consumption and incidence of shoulder pain or adverse effects at 24 h.

Intravenous tramadol provides superior postoperative analgesia in the early postoperative period after laparoscopic cholecystectomy compared with an equivalent dose of tramadol administered intraperitoneally and with normal saline in patients undergoing laparoscopic cholecystectomy.

In Germany there is considerable variability in the organizational forms of intensive-care medicine. We present economical data that arose during the reorganization of an intensive care unit with the implementation of the continuous presence of a trained intensivist. The unit was changed from an intensive-observational unit managed by four surgical departments without continuous presence of a trained intensivist to an interdisciplinary surgical intensive care unit managed by the Department of Anaesthesia in co-operation with the surgical departments with the continuous presence of trained intensivists.

Measurement of costs for personnel, medical equipment and external services, revenues, length of hospital stay and complications of cardiac surgical patients.

Per year costs for personnel increased by approximately €240 000, while expenses for medical equipment were reduced by €245 000. In all, 466 hospital days were saved by the reduction in the length of hospital stay, providing capacity for 22 additional cardiac surgical cases. In addition, the presence of trained intensivists made it possible to provide care for more severely ill patients, which gained approximately 100 additional case-mix points and increased the hospital’s revenues by more than €300 000. Emergency readmission to the intensive care unit was reduced by 17%. The number of patients requiring renal replacement therapy and those developing non-occlusive mesenteric ischaemia was substantially reduced.

In addition to the medical advantages, staffing the intensive care unit with trained intensivists 24 h a day was of appreciable economical benefit.

Dynamic indices represented by systolic pressure variation and pulse pressure variation have been demonstrated to be more accurate than filling pressures in predicting fluid responsiveness. However, the literature is scarce concerning the impact of different ventilatory modes on these indices. We hypothesized that systolic pressure variation or pulse pressure variation could be affected differently by volume-controlled ventilation and pressure-controlled ventilation in an experimental model, during normovolaemia and hypovolaemia.

Thirty-two anaesthetized rabbits were randomly allocated into four groups according to ventilatory modality and volaemic status where G1-ConPCV was the pressure-controlled ventilation control group, G2-HemPCV was associated with haemorrhage, G3-ConVCV was the volume-controlled ventilation control group and G4-HemVCV was associated with haemorrhage. In the haemorrhage groups, blood was removed in two stages: 15% of the estimated blood volume withdrawal at M1, and, 30 min later, an additional 15% at M2. Data were submitted to analysis of variance for repeated measures; a value of P < 0.05 was considered to be statistically significant.

At M0 (baseline), no significant differences were observed among groups. At M1, dynamic parameters differed significantly among the control and hypovolaemic groups (P < 0.05) but not between ventilation modes. However, when 30% of the estimated blood volume was removed (M2), dynamic parameters became significantly higher in animals under volume-controlled ventilation when compared with those under pressure-controlled ventilation.

Under normovolaemia and moderate haemorrhage, dynamic parameters were not influenced by either ventilatory modalities. However, in the second stage of haemorrhage (30%), animals in volume-controlled ventilation presented higher values of systolic pressure variation and pulse pressure variation when compared with those submitted to pressure-controlled ventilation.

Our aim was to investigate the cytoprotective effect of propofol against hydrogen peroxide (H2O2)-mediated injury and the effects on the haeme oxygenase-1 system, which is a possible new cytoprotective pathway of propofol.

Primary cultured newborn rat cardiomyocytes were divided into five groups: (1) untreated (Group control); (2) treated with 200 μmol L−1 H2O2 (Group H) and treated with 200 μmol L−1 H2O2 in the presence of propofol (25, 50 and 100 μmol L−1, (3) Group 25P + H, (4) Group 50P + H and (5) Group 100P + H, respectively); added with zinc protoporphyrin IX (ZnPPIX) (10 μmol L−1), a potent inhibitor of haeme oxygenase activity, or SC-3060 (0.2 μL mL−1), a specific synthetic inhibitor of nuclear factor κB. All were incubated for 6 h. The protective effects of propofol were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide cytotoxicity assay, the concentration of malondialdehyde, superoxide dismutase activity and cell apoptosis by enzyme-linked immunosorbent assay (ELISA). Reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis were used to detect haeme oxygenase-1 expression.

Compared with H2O2, propofol concentrations (ranging from 50 to 100 μmol L−1) significantly increased haeme oxygenase-1 expression and decreased cardiomyocytes apoptosis, accompanied with a decrease in malondialdehyde, but with an increase in superoxide dismutase activity and cell activity (P < 0.05 and P < 0.01, respectively). The protective effects of propofol were mitigated by the addition of ZnPPIX. The addition of SC-3060 reversed propofol-induced haeme oxygenase-1 expression.

Propofol can protect cardiomyocytes against H2O2-mediated cytotoxicity in a dose-dependent manner and increase haeme oxygenase-1 expression, which may partly mediate the cytoprotective effects of propofol.

α2-Adrenoceptor agonists administered into the intrathecal and epidural space have been found to be effective in the treatment of chronic pain. Moreover, it was shown that they increase the analgesic effects of local anaesthetics and provide sedation, anxiolysis and haemodynamic stability. Dexmedetomidine, a potent and highly selective α2-adrenoceptor agonist, is in current clinical use, particularly in the intensive care unit. Our aim was to investigate whether dexmedetomidine produced motor and sensory blockade and neurotoxic effects when administrated via the epidural catheter in rabbits.

Twenty-one New Zealand white rabbits were included in the study. Animals were randomized into three groups. In Group L: lidocaine (2%), in Group LD: lidocaine (2%) + dexmedetomidine (5 μg) and in Group D: dexmedetomidine (10 μg) were administered by epidural catheter. Motor and sensory blockade were evaluated. After the evaluation of block, the animals were euthanized and their spinal cords removed for neuropathological evaluations.

Motor and sensory blockade were lower in Group D than in Group L and Group LD (P < 0.01). Although there were no differences between the groups for ischaemia of the medulla spinalis, evidence of demyelinization of the oligodendrocytes in the white matter in Group D was significantly higher than in Group L (P = 0.035).

We observed that dexmedetomidine does not have motor and sensory effects, but it may have a harmful effect on the myelin sheath when administered via the epidural route.

The aim of this open, non-controlled, multi-centre study was to evaluate the pharmacokinetics and safety of a 24–72 h continuous epidural ropivacaine infusion in children aged 1–9 yr.

After induction of general anaesthesia, 29 ASA I–II children, scheduled for major surgery in dermatomes below T10 had lumbar epidural catheters placed. A bolus of ropivacaine, 2 mg kg−1, was given over 4 min, followed immediately by an infusion of 2 mg mL−1 ropivacaine 0.4 mg kg−1 h−1 for the next 24–72 h.

Plasma concentrations of total ropivacaine (mean 0.83 and 1.06 mg L−1 at 16–31 and 59–72 h, respectively) and α1-acid-glucoprotein (mean 13 and 25 μmol L−1 at baseline and 59–72 h) increased over the course of the infusion. Plasma concentrations of unbound ropivacaine were stable throughout the epidural infusion (mean 0.021 range 0.011–0.068 and mean 0.016 range 0.009–0.023 mg L−1 at 16–31 and 59–72 h, respectively) and were well below threshold levels associated with central nervous system toxicity in adults (0.35 mg L−1). Apparent unbound clearance (mean 346, range 86–555 mL min−1 kg−1) showed no age-dependency. No signs of systemic toxicity or cardiovascular effects were observed. All patients received additional analgesics with morphine.

Following a 24–72 h epidural infusion of ropivacaine 0.4 mg kg−1 h−1 in 1–9-yr-old children, the plasma concentrations of unbound ropivacaine were stable over time with no age-dependency.

Adequate analgesia is needed after total hip arthroplasty to control pain at rest and during rehabilitation. Our aim was to compare, in a randomized study, the efficacy of two analgesia regimens in control of postoperative pain after total hip arthroplasty: opioid-free continuous psoas compartment block vs. an opioid/non-steroidal anti-inflammatory drugs continuous intravenous infusion.

In all, 73 patients (ASA I–III), aged 61–82 yr, undergoing total hip arthroplasty were prospectively enrolled in a single-blind randomized trial. Patients were allocated either to the study group (Group A, n = 37) or to the control group (Group B, n = 36). Patients in Group A underwent preoperative placement of a catheter in the psoas compartment and, 30 min before the end of surgery, the catheter was primed with a loading dose of 0.75% ropivacaine (0.4 mL kg−1) followed by a continuous infusion of 10 mL h−1 ropivacaine 0.2% for 48 h. Patients in Group B received, from 1 h before the end of surgery, a continuous intravenous infusion of 0.1% morphine and 0.12% ketorolac at 2 mL h−1 for 48 h. Both groups received spinal anaesthesia for surgery. Pain scores at rest and after mobilization, amount of rescue analgesia, nausea/vomiting and haemodynamic parameters were recorded.

In Group A, median pain scores were very low during the whole study duration both at rest and during physiotherapy in comparison to Group B. Less rescue analgesia was needed and less nausea and vomiting was observed in Group A.

Opioid-free continuous psoas compartment block seems to be an appropriate and reliable technique in providing effective postoperative analgesia at rest and during physiotherapy after total hip arthroplasty when compared to intravenous morphine/ketorolac infusion.