Hepatocellular integrity in patients requiring parenteral nutrition: comparison of structured MCT/LCT vs. a standard MCT/LCT emulsion and a LCT emulsion.

BACKGROUND AND OBJECTIVE: The aetiology of parenteral nutrition-associated hepatic injury remains unresolved. The aim of the study was to evaluate the effects of structured triglycerides in parenteral nutrition compared either to a physical medium-chain triglycerides (MCT)/long-chain triglcerides (LCT) mixture or to a LCT emulsion on hepatic integrity. METHODS: In a randomized, double-blinded trial, we studied 45 patients undergoing abdominal surgery, who were expected to receive parenteral nutrition for 5 days. Patients were allocated to one of three nutrition regimens: Group A (n = 15) received structured triglycerides, Group B (n = 15) a MCT/LCT and Group C (n = 15) a LCT lipid emulsion. Before the start of parenteral nutrition (T0), 24 h (T1), 48 h (T2), 72 h (T3) and 120 h (T4) after start of infusion the following parameters were measured: Alpha-glutathione S-transferase (alpha-GST), alanine aminotransferase (ALT), aspartate aminotransferase (AST), glucose and serum triglycerides. RESULTS: At T3 and T4, alpha-GST levels were significantly higher in Group B (T3: 9.4 +/- 9.9; T4: 14.6 +/- 19.5 microg L-1) and Group C (T3: 14.2 +/- 20.8; T4: 22.4 +/- 39.3 microg L-1) compared with the patients receiving structured triglycerides (T3: 1.9 +/- 1.8; T4: 3.2 +/- 2.7 microg L-1). Whereas the mean alpha-GST-levels in structured triglycerides group always remained in the normal range, this was not the case in both other groups at T3 and T4. There were no significant differences concerning ALT, AST and glucose levels. At T3 and T4, triglyceride levels were significantly lower in Group A than in Groups B and C. CONCLUSIONS: Hepatic integrity was well retained with the administration of structured triglycerides, whereas both MCT/LCT emulsion and LCT emulsion caused subclinical hepatic injury.

Prevention of atrial fibrillation after coronary artery bypass graft surgery using a potassium-magnesium-aspartate solution (Inzolen).

BACKGROUND: Atrial fibrillation (AFIB) following cardiac surgery is a frequent complication. The purpose of this study was to evaluate the efficacy of a potassium-magnesium-aspartate solution (Inzolen) for the prevention of AFIB. METHODS: In a randomised, prospective, double-blinded study, we studied 88 patients undergoing elective coronary artery bypass graft surgery (CABG). After surgery, patients were allocated randomly to one of two groups. Group A (n = 43) received a potassium-magnesium-aspartate solution (Inzolen), group B (n = 45) received potassium chloride; both solutions were administered continuously for 48 hours to keep the potassium serum levels between 4.5 and 5.5 mmol/l. Patients were observed for 5 days postoperatively and the incidence of atrial fibrillation was noted. At the end of surgery (T0), 4 h (T1), 24 h (T2), 48 h (T3), and 120 h (T4) postoperatively, magnesium and potassium serum levels were measured. RESULTS: The two groups did not differ significantly with regard to demographics and perioperative data. No significant difference in the incidence of postoperative atrial fibrillation was seen (group A: 41.9 % vs. group B 31.1 %; P = 0.53). In group A, the magnesium serum levels were significantly higher at T1 (1.15 +/- 0.18 vs. 0.87 +/- 0.11 mmol/l), T2 (1.24 +/- 0.22 vs. 0.82 +/- 0.10 mmol/l) and T3 (1.15 +/- 0.18 vs. 0.81 +/- 0.20 mmol/l) compared to group B, whereas potassium levels were similar in the two groups throughout the study period. CONCLUSIONS: The use of a potassium-magnesium-aspartate solution (Inzolen) showed no significant difference in potassium chloride for the prophylaxis of postoperative atrial fibrillation secondary to CABG.

Influence of controlled hypotension using esmolol and sodium nitroprusside on natriuretic peptides in patients undergoing endonasal sinus surgery.

BACKGROUND AND OBJECTIVE: Atrial and brain natriuretic peptide, synthesized by cardiac myocytes, are mediators secreted secondary to cardiac volume expansion and increased filling pressure. The study was designed to assess serum concentration of atrial and brain natriuretic peptide in patients undergoing endonasal sinus surgery receiving controlled hypotension. METHODS: We studied 45 patients without cardiovascular history, scheduled for elective endonasal sinus surgery. Patients were allocated to one of three groups: controlled hypotension was induced either by using esmolol (n = 15) or sodium nitroprusside (n = 15) with a mean arterial pressure of 50-55 mmHg. In the control group (n = 15), mean arterial pressure was adjusted to 70-80 mmHg. Atrial and brain natriuretic peptides were measured preoperatively (T1), at the end of surgery (T2), 2 h (T3), 24 h (T4) and 48 h (T5) postoperatively. RESULTS: Preoperative atrial and brain natriuretic peptide plasma levels were within normal ranges and similar between all groups. Patients treated with esmolol (atrial natriuretic peptide: 2.46 +/- 0.75 microg mL(-1) brain natriuretic peptide: 4.34 +/- 3.06 microg mL(-1)) and sodium nitropusside (atrial natriuretic peptide: 2.48 +/- 0.92 microg mL(-1); brain natriuretic peptide: 4.49 +/- 3.21 microg mL(-1)) showed significantly lower concentrations of atrial and brain natriuretic peptide at T2 and T3 compared with controls (atrial natriuretic peptide: 5.31 +/- 2.32 microg mL(-1); brain natriuretic peptide: 13.26 +/- 8.98 microg mL(-1)) , P < 0.01) as well as a reduction in blood loss and duration of surgery. CONCLUSIONS: Controlled hypotension decreases the release of natriuretic peptides in cardiovascular healthy patients. This effect may be contributed to by changes in cardiac filling pressure due to lower systemic resistance and diminished perfusion pressure.

Inspired oxygen fraction of 0.8 compared with 0.4 does not further reduce postoperative nausea and vomiting in dolasetron-treated patients undergoing laparoscopic cholecystectomy.

BACKGROUND: Postoperative nausea and vomiting (PONV) is one of the most frequent complications after general anaesthesia. Single-dose antiemetic prophylaxis has limited efficacy in high-risk patients. Adding a simple potential antiemetic approach, such as increasing the inspired oxygen fraction, to the antiemetic portfolio would preserve pharmacological interventions for treatment of symptoms in the postoperative period. However, the antiemetic effect of a high inspired oxygen fraction is still discussed controversially. The aim of the study was to evaluate whether an inspired oxygen fraction of 0.8 decreases PONV in patients receiving the 5-HT3-antagonist dolasetron. METHODS: In a randomized, placebo-controlled, double-blinded trial we studied 377 patients (ASA I-III) undergoing elective laparoscopic cholecystectomy. Induction of anaesthesia was standardized, including thiopental fentanyl and cis-atracurium. For all patients the individual risk for PONV was calculated using the Koivuranta score and all patients received 12.5 mg dolasetron i.v. before surgery. Patients were allocated randomly to one of three groups: Group A (n=125) received 80% oxygen in air, Group B (n=125) 40% oxygen in air and Group C (n=127) 40% oxygen in nitrous oxide. Postoperative nausea, postoperative vomiting (PV), or nausea, vomiting, or both (PONV) was assessed in the early (0-4 h) and overall postoperative period (0-24 h) by an anaesthesiologist unaware of patient allocation. RESULTS: There was a significantly lower incidence of PONV and PV in Groups A (PONV: 11.2%; PV: 3.2%) and B (PONV: 10.4%; PV: 3.2%) compared with Group C (PONV: 26.7%; PV: 13.3%), but there were no significant differences between Groups A and B. CONCLUSIONS: An inspired oxygen fraction of 0.8 does not further decrease PONV or vomiting in dolasetron-treated patients undergoing laparoscopic cholecystectomy. The lower incidence of PONV in Groups A and B compared with Group C is most likely caused by the omission of nitrous oxide.

Physostigmine for the prevention of postanaesthetic shivering following general anaesthesia - a placebo-controlled comparison with nefopam.

Physostigmine was studied for its efficacy in the prevention of postanaesthetic shivering compared to nefopam and placebo. We studied 89 patients undergoing abdominal and urological surgery. The study was randomised and double-blind, the patients received physostigmine 2 mg (n = 31), nefopam 10 mg (n = 30) or saline (n = 28). Haemodynamic parameters and temperature were measured at induction of anaesthesia (T0), and 5 min (T1), 15 min (T2), 30 min (T3) and 60 min (T4) after reaching the postanaesthetic care unit (PACU). Significantly less shivering occurred following administration of physostigmine and nefopam (9.7 and 3.3%) compared to placebo (53.6%). The degree of shivering was also significantly reduced following physostigmine and nefopam (p < 0.01). Extubation time, haemodynamic parameters and tympanic temperature were found to be similar in all groups. Aldrete score, duration of PACU stay and postoperative analgesic requirements did not differ between the groups. Only nefopam significantly (p < 0.01) reduced postoperative nausea and vomiting. Physostigmine is a safe alternative to nefopam, significantly reducing the incidence and severity of postanaesthetic shivering without affecting postanaesthetic recovery.

Insignificant effect of desflurane-fentanyl-thiopental on hepatocellular integrity--a comparison with total intravenous anaesthesia using propofol-remifentanil.

BACKGROUND AND OBJECTIVE: Inhalational anaesthetics have been associated with hepatotoxicity. Even desflurane, with its low solubility in blood and tissues, and its minimal hepatic biotransformation, is known to affect hepatic integrity. The effects of propofol on hepatic function are, however, a matter of controversy. Alpha-glutathione S-transferase (alpha-GST), a sensitive and specific biomarker for hepatic integrity, was measured to assess the influence of total intravenous anaesthesia (TIVA) with propofol vs. anaesthesia with desflurane. METHODS: Forty-two patients scheduled for elective prostatectomy were randomly allocated to receive either desflurane, fentanyl and thiopental (desflurane group) or propofol and remifentanil (TIVA group). Depth of anaesthesia was guided by bispectral index. Plasma concentrations of alpha-GST and aminotransferases were measured before induction of anaesthesia (TO), at the end of surgery (T1), as well as 2 h (T2) and 24 h (T3) postoperatively. Haemodynamic parameters and bispectral index values were documented. RESULTS: alpha-GST increased significantly in the desflurane group from TO (3.0 +/- 2.2 microg L(-1)) to T1 and T2 (5.5 +/- 4.3 and 5.6 +/- 3.7 microg L(-1), respectively), whereas no changes were seen in the TIVA group. alpha-GST values above the normal upper limit (> 7.5 microg L(-1)) were seen in 24% of the patients receiving desflurane. Aminotransferases remained unchanged in both groups throughout the study period. CONCLUSIONS: The use of propofol as part of a TIVA regimen seems to have no influence on hepatocellular function during and after surgery. In contrast, patients receiving desflurane showed a transient slight, but significant, increase of alpha-GST to above the normal upper limit after anaesthesia, although this was without further clinical relevance.

A comparison of nefopam and clonidine for the prevention of postanaesthetic shivering: a comparative, double-blind and placebo-controlled dose-ranging study.

Postanaesthetic shivering is a frequent complication following general anaesthesia. The aim of this study was to compare the effectiveness of three doses of nefopam with clonidine and placebo in the prevention of postanaesthetic shivering. We studied 371 patients undergoing abdominal or orthopaedic surgery. Patients were allocated to one of five groups: Group A (n = 73) received 0.2 mg x kg(-1) nefopam, Group B (n = 75) 0.1 mg x kg(-1) nefopam, Group C (n = 76) 0.05 mg x kg(-1) nefopam, Group D (n = 73) 1.5 microg x kg(-1) clonidine, and Group E (n = 74) saline 0.9% as placebo. We found a significant reduction in the incidence of shivering in Group A compared to Group C and clonidine as well as to the placebo group. All active treatments reduced the incidence and the severity of shivering compared to placebo. At 5 min postoperatively clonidine-treated patients showed a significant decrease in MAP and a significantly lower Aldrete score compared to all other groups. No haemodynamic or sedative adverse events were observed in the nefopam-treated patients. The results of our study indicate that nefopam (0.2 mg x kg(-1)) is superior to clonidine (1.5 microg x kg(-1)) in the prophylaxis of postanaesthetic shivering and not accompanied by sedative or haemodynamic side-effects.

[Injection pain secondary to propofol-MCT/LCT and propofol-LCT--comparison of prophylaxis with lidocaine]. / Injektionsschmerz unter Propofol-MCT/LCT und Propofol-LCT - Vergleich einer Prophylaxe mit Lidocain.

OBJECTIVE: Pain on injection is one of the most described side-effects of the intravenous application of propofol. This study was designed to assess the efficacy of lidocaine 40 mg in preventing incidence and severity of injection pain for two different propofol solvents. METHODS: In a double-blind and prospective study 202 patients were enrolled and randomized to 4 different groups: group A receiving 2 ml NaCl 0.9 % and propofol-LCT (Disoprivan; AstraZeneca), group B 40 mg lidocaine and propofol-LCT, group C received 2 ml NaCl 0.9 % and propofol-MCT/LCT (Propofol-Lipuro, B. Braun Melsungen AG) and group D 40 mg lidocaine and propofol-MCT/LCT. According to the protocol, all patients were cannulated with a 18-G venous cannula at the dorsum of the hand and no other medicament was injected before the study drug. Time interval between test agents and propofol application in a dosage of 2 mg/kg was one minute. Severity of pain was evaluated during propofol injection over 30 seconds until loss of consciousness using a 4-point rating scale. RESULTS: The incidence of injection pain did not differ between propofol-LCT and propofol-MCT/LCT (64 % and 53 %). Propofol-MCT/LCT significantly reduced the severity of pain compared to propofol-LCT (p < 0.05). The application of lidocaine resulted in a significant reduction in incidence (Propofol-MCT/LCT: 16 %; Propofol-LCT: 31 %) and severity of injection pain compared to placebo. CONCLUSION: Propofol-MCT/LCT showed a significant advantage compared to propofol-LCT considering the severity of injection pain, but not in reducing the incidence of pain. The use of lidocaine resulted in a significant reduction of incidence and severity of injection pain for both propofol solvents.

[Influence of cardiopulmonary bypass (CPB) on the natriuretic peptides ANP and BNP. A comparison between long and short duration of CPB and off pump surgery]. / Einfluss der extrakorporalen Zirkulation (EKZ) auf die natriuretischen Peptide ANP und BNP. Ein Vergleich zwischen langen und kurzen EKZ-Zeiten sowie Off-Pump-Eingriffen.

OBJECTIVE: Plasma atrial and brain natriuretic peptide (ANP and BNP) are cardiac hormones secreted mainly due to cardiac overload. The study was designed to assess plasma concentrations of ANP and BNP in patients undergoing coronary bypass grafting (CABG) with long and short duration of cardiopulmonary bypass (CPB) and without CPB (off-pump surgery). METHODS: We studied 45 patients scheduled for elective CABG. Patients were allocated in three groups: group A received CPB with a duration less than 60 minutes, group B more than 60 minutes and patients without CPB were allocated in group C. ANP and BNP were measured after induction of anaesthesia (T0), at the end of surgery (T1), 4 hrs. (T2), 24 hrs. (T3) and 120 hrs. postoperatively (T4). RESULTS: In all groups, ANP-levels increased from T0 to T4 (group A: from 3.7 +/- 2.1 to 8.9 +/- 8.0; group B: from 3.3 +/- 1.7 to 8.0 +/- 6.0; group C: from 3.0 +/- 1.6 to 5.3 +/- 2.3 pg/ml), but there were no significant differences between the groups. BNP-concentrations increased also from T0 to T4 (group A: from 34 +/- 18 to 234 +/- 164; group B: from 33 +/- 26 to 219 +/- 182; group C: from 33 +/- 24 to 77 +/- 55 pg/ml). Furthermore we measured significant higher BNP-levels in group B compared to group C at T3 and T4. No significant differences between group A and B were found. CONCLUSIONS: CPB influenced BNP, but not ANP plasma concentrations. An influence of the duration of CPB on ANP and BNP was not seen.

[Current status of non-invasive ventilation in German ICU's -- a postal survey]. / Umfrage zum Stellenwert der non-invasiven Ventilation auf Deutschen Intensivstationen.

The status of non-invasive ventilation (NIV) in intensive care units (ICU) in Germany was analysed by a national survey. Questionnaires consisting of multiple-choice and short-answer questions were sent to ICUs of university hospitals, hospitals with >1000 beds, with 500 - 1000 beds, and hospitals with <500 beds separated with regard to different specialties (anesthesia ICUs, surgical ICUs, cardiac surgical ICUs, neurosurgical ICUs, internal ICUs, interdiscipline ICUs). Of the 716 questionnaires sent 223 (32 %) were returned and analysed. The use of NIV in all specialties increased during the last 3 years. 14 % of ICUs in some specialties treated more than 30 % of patients with NIV. CPAP (88 %), BIPAP (45 %) and ASB/PSV (48 %) were most frequently used as NIV-strategies. 10 % of all ICUs reported to have experience with proportional assist ventilation. NIV was most frequently used for disease states like COPD (82 %), pneumonia (64 %), pulmonary oedema (50 %), bronchial asthma (35 %) and ALI/ARDS (22 %). The use of NIV was considered when clinical signs of ventilation (93 %) and oxygenation [arterial blood gas analysis (92 %) and oxygen saturation (66 %)] were inadequate. Complications observed during NIV were panic reaction (83 %), ulceration of nose (38 %) and aspiration (14 %). The reasons to reject NIV were (total 13 %): lack of ventilators (64 %), expenditure of personnel (57 %) and risk of the procedure (11 %). 38 % of the ventilators used were older than 5 years. 56 % of the ICUs were content with the equipment for NIV. 76 % of the ICUs were interested to buy new equipment of NIV. 99 % of the survey have declined NIV as an alternative method of ventilation. In summary we found NIV as an accepted additional method of ventilatory support in respiratory failure in German ICUs. We found no significant increase in frequency of NIV in the last three years.

Effects of sodium nitroprusside-induced controlled hypotension on pancreatic function assessed by pancreatitis-associated protein in patients undergoing radical prostatectomy.

BACKGROUND AND OBJECTIVE: Controlled hypotension may alter organ blood flow and tissue oxygenation. The aim of the study was to investigate whether induced hypotension using sodium nitroprusside alters pancreatic function assessed by pancreatitis-associated protein concentrations in the blood. METHODS: Thirty patients undergoing elective radical prostatectomy were allocated randomly into two groups: (a) hypotension group: sodium nitroprusside was administered to lower mean arterial pressure to approximately 50 mmHg; (b) control group: no hypotension was used, mean arterial pressure was kept > 70 mmHg. Pancreatitis-associated protein and lipase were measured in arterial blood samples: after induction of anaesthesia (T1), at the end of surgery (T2), 2 h (T3) and 24 h (T4) postoperatively. RESULTS: Pancreatitis-associated protein plasma concentrations increased significantly in patients in the hypotensive group (from 2.8 +/- 1.1 to 5.5 +/- 2.0 micrograms L-1 at T4) and pancreatitis-associated protein plasma concentrations were significantly higher in comparison with controls (5.5 +/- 2.0 versus 3.5 +/- 2.4 micrograms L-1) at T4. Lipase concentrations showed a similar course in both groups. None of the patients showed clinical signs of pancreatitis. CONCLUSIONS: Controlled hypotension during surgery was associated with a small but significant increase in pancreatitis-associated protein compared with controls. The absence of concomitant elevation in lipase concentrations and a lack of clinical evidence of pancreatitis damage suggest that hypotension induces mild pancreatic stress.

Urapidil does not prevent postanesthetic shivering: a dose-ranging study.

PURPOSE: To investigate the effect of 0.2 mg x kg(-1), 0.3 mg x kg(-1) and 0.4 mg x kg(-1) urapidil on the incidence and severity of postanesthetic shivering. METHODS: One hundred and fifty patients (ASA I-III) scheduled for elective abdominal, urologic or orthopedic surgery under standardized general anesthesia were randomly allocated to one of five groups (each group n=30) using a double-blind protocol: group A received 0.2 mg x kg(-1) urapidil, group B: 0.3 mg x kg(-1) urapidil, group C: 0.4 mg x kg(-1) urapidil, group D: 3 microg x kg(-1) clonidine (positive control group), and group E: saline 0.9% as placebo (negative control group). Postanesthetic shivering was scored using a five-point scale. RESULTS: Twelve patients of group A, 11 of group B, nine of group C, three of group D and 14 of group E showed signs of postanesthetic shivering. Postanesthetic shivering was significantly decreased in the clonidine group compared to the three urapidil groups and the placebo group. Significantly less patients treated with clonidine needed anti-shivering therapy. There were no significant differences between the urapidil and placebo groups. Therapeutic interventions for hemodynamic effects were not required in any group. Time to extubation, but not time to discharge, was prolonged in the clonidine group. CONCLUSION: Urapidil showed no beneficial effect on shivering in any of the doses evaluated, whereas prophylactic administration of clonidine was effective in preventing postanesthetic shivering.

Effects of postoperative sedation with propofol and midazolam on pancreatic function assessed by pancreatitis-associated protein.

This prospective randomised controlled study evaluated the effects of postoperative sedation with propofol and midazolam on pancreatic function. We studied 42 intensive care unit patients undergoing elective major surgery who were expected to be sedated postoperatively. Patients were randomly assigned to a propofol group (n = 21) or a midazolam group (n = 21). To assess pancreatic function, the following parameters were measured: pancreatitis-associated protein, amylase, lipase, cholesterol and triglyceride prior to start of sedation on the intensive care unit, 4 h after the sedation was started and at the first postoperative day. Patients in the propofol group received on average (SD) 1292 (430) mg propofol and were sedated for 9.03 (4.26) h. The midazolam group received 92 (36) mg midazolam and were sedated for 8.81 (4.68) h. Plasma cholesterol concentrations did not differ significantly between groups. Triglyceride plasma levels 4 h after the start of infusion were significantly higher in the propofol group (140 (54) mg.dl(-1)) than the midazolam-treated patients (81 (29) mg.dl(-1)), but were within normal limits. There were no significant differences between the two groups regarding amylase, lipase and pancreatitis-associated protein plasma concentrations at any time. No markers of pancreatic dysfunction were outside the normal range. We conclude that postoperative sedation with propofol induced a significant increase of serum triglyceride levels but that pancreatic function is unchanged with standard doses of propofol.

Does age affect liver function and the hepatic acute phase response after major abdominal surgery?

OBJECTIVE: The liver plays a key role in the inflammatory response during major surgery or infection. The influence of age on liver function and hepatic acute phase protein (APP) synthesis should be serially studied in elderly patients undergoing major abdominal surgery. DESIGN AND SETTING: Prospective and descriptive study over 3 days. Clinical investigation in the operating room and surgical intensive care unit (ICU) of a tertiary care hospital. PATIENTS AND INTERVENTIONS: 42 consecutive patients were grouped according to age: less than 60 years ("adult") or over 65 years ("elderly") and prospectively studied. All patients received standardized general anesthesia and were treated afterwards according to the standard protocols of our ICU. Intensivists caring for the patients were not involved in the study and were blinded to data analysis. MEASUREMENTS AND RESULTS: Concentrations of interleukin (IL)-6, serum amyloid A (SAA), C-reactive protein (CRP), alpha1-antitrypsin (alpha1-AT), and haptoglobin were measured to assess the APP response. Liver function was evaluated by the monoethylglycinexylidide (MEGX) test and by measuring alpha-glutathione S-transferase (alpha-GST). All measurements were performed at induction of anesthesia (T0), at the end of surgery (T1), and 2 h (T2), 24 h (T3), and 48 h (T4) postoperatively. There was no difference in the incidence of postoperative septic complications between the two groups. Baseline values of IL-6 and the four APPs were normal in all patients and did not differ between the groups. IL-6 levels increased significantly in all patients at T1 and T2, with a significantly higher increase in the older patients (elderly: from 7.4+/-3.4 pg/ml to 220.6+/-49.5 pg/ml; adult: from 6.2+/-2.5 pg/ml to 189.9+/-36.8 pg/ml). A return to baseline values was seen at T3 in both groups. Concentrations of all APPs, except for haptoglobin, started to increase at T3. Peak concentrations were significantly lower in the elderly patients (elderly: SAA 358+/-133 microg/l, CRP 5.1+/-2.3 mg/dl, alpha1-AT 160+/-96 mg/dl; adult: SAA 444+/-100 microg/l, CRP 8.5+/-3.2 mg/dl, alpha1-AT 223+/-85 mg/dl). Baseline alpha-GST and MEGX concentrations were normal in all patients. Alpha-GST concentrations increased in both groups at T1 and T2, with a significantly higher increase in the older patients (elderly: 3.7+/-1.4 microg/l to 10.2+/-2.9 microg/l; adult 4.5+/-2.1 microg/l to 8.5+/-1.7 microg/l). A return to baseline values was seen at T3 in both groups. MEGX concentrations were significantly lower and abnormal (<50 ng/ml) in the older patients at T3 and T4. CONCLUSIONS: Our observations suggest that the postoperative hepatic acute phase response is reduced in elderly patients undergoing major abdominal surgery. The decreased release of liver-synthesized APPs was associated with an impaired hepatocyte function and a disturbance of hepatocellular integrity. Further work needs to be done to determine whether these findings might have an impact on the incidence of postoperative septic complications or prognostic significance for survival in aged patients.

Cerebral effects and blood sparing efficiency of sodium nitroprusside-induced hypotension alone and in combination with acute normovolaemic haemodilution.

The combined reduction of oxygen-carrying capacity and perfusion pressure during the combination of acute normovolaemic haemodilution (ANH) and controlled hypotension (CH) raises concerns of hypoperfusion and ischaemic injury to the brain. Forty-two patients undergoing radical prostatectomy were prospectively allocated to receive CH induced by sodium nitroprusside (mean arterial pressure (MAP) 50 mm Hg), a combination of CH+ANH (post-ANH haematocrit 29%; intraoperative MAP 50 mm Hg), or standard anaesthesia (control). Serum levels of the brain-originated proteins neuron-specific enolase (NSE) and protein S-100, blood loss, transfusion requirements, adverse effects, and postoperative recovery profile were compared among the three groups. Intraoperative blood loss in the CH group (mean (SD)) (788 (193) ml) and CH+ANH group (861 (184) ml) was significantly less than in the control group (1335 (460) ml). Significantly fewer total units of allogeneic packed red blood cells (PRBC) were transfused in the patients receiving hypotensive anaesthesia (CH, 3 units; CH+ANH, 2 units; control, 17 units). There was no difference in immediate postoperative recovery profile among the three groups as determined by the emergence from anaesthesia and time to discharge from the postanaesthesia care unit. Serum S-100 protein concentrations increased significantly in all groups from baseline to peak concentrations 2 h postoperatively (CH 0.25 (0.11) microg litre(-1); CH+ANH 0.31 (0.12) microg litre(-1); control 0.31 (0.10) microg litre(-1)). A return to baseline values was seen within 24 h postoperatively in all patients. No changes in NSE concentrations were seen. Our observations suggest that CH and CH+ANH were effective in reducing blood loss and transfusion requirements in patients undergoing radical prostatectomy. Increased serum S-100 protein concentrations imply a disturbance in astroglial cell membrane integrity and an increased endothelial permeability of the blood-brain barrier. There were no associations between serum S-100 protein or NSE and adverse cognitive effects. Further work needs to be done to determine the prognostic importance of S-100 protein and NSE as surrogate variables of postoperative cerebral complications.

Low-flow desflurane and sevoflurane anesthesia minimally affect hepatic integrity and function in elderly patients.

UNLABELLED: Hepatic blood flow is reduced in a dose-related manner by all inhaled anesthetics now in use. We assessed hepatic function in elderly patients anesthetized with desflurane or sevoflurane. We measured the cytosolic liver enzyme alpha glutathione S-transferase (alpha GST), the formation of the lidocaine metabolite monoethylglycinexylidide (MEGX), and gastric mucosal tonometry-derived variables as sensitive markers of hepatic function and splanchnic perfusion. Thirty patients, 70 to 90 yr old, were allocated randomly to receive desflurane or sevoflurane anesthesia. Anesthetic exposure ranged from 2.1-4.5 minimum alveolar concentration hours. No significant changes in standard liver enzyme markers were seen throughout the study. In both anesthetic groups, tonometric measurements showed a significant decrease from baseline in regional PCO(2), regional to arterial difference in PCO(2), and intramucosal pH at 90 min after skin incision. alpha GST concentrations increased significantly in both groups (desflurane: median peak concentrations 5.8 microg/L [25th, 75th percentile 5.3 microg/L, 7.2 microg/L]; sevoflurane: 7.0 microg/L [5.8 microg/L, 7.3 microg/L]) without showing differences between both anesthetic groups. A return to baseline values in tonometric values and alpha GST levels was seen 24 h postoperatively. MEGX formation did not change significantly after surgery. Median MEGX concentrations postoperatively were 70.0 ng/mL (56.2 ng/mL, 102.0 ng/mL) and 70.0 ng/mL (60.0 ng/mL, 94.2 ng/mL) in the desflurane and sevoflurane groups, respectively. We conclude that, overall, liver function in elderly patients is well preserved during desflurane and sevoflurane anesthesia. Increased serum levels of alpha GST and changes of gastric tonometry-derived variables imply a reduction in splanchnic perfusion, leading to a temporary impairment of hepatocyte oxygenation. IMPLICATIONS: We measured the lidocaine metabolite monoethylglycinexylidide, the cytosolic liver enzyme, alpha glutathione S-transferase, and gastric mucosal tonometry-derived variables to evaluate the effects of desflurane and sevoflurane on hepatic function in elderly patients. Liver function was well preserved, whereas increased alpha glutathione S-transferase levels and changes in tonometry-derived variables indicated a reduction in splanchnic blood flow and a temporary impairment of hepatocyte oxygenation for both anesthetics.

A comparison of urapidil, clonidine, meperidine and placebo in preventing postanesthetic shivering.

UNLABELLED: This placebo-controlled study was performed to evaluate the efficacy of urapidil compared with clonidine and meperidine in preventing postanesthetic shivering, which is common after anesthesia administration and may be very distressing. We studied 120 patients undergoing elective abdominal or orthopedic surgery under standardized general anesthesia. After surgery, patients were randomly assigned to one of four groups (each group n = 30) using a double-blinded protocol: Group A received 0.2 mg/kg urapidil; Group B, 3 microg/kg clonidine; Group C, 0.4 mg/kg meperidine; and Group D, saline 0.9% as placebo. Postanesthetic shivering was scored by using a five-point scale. Clonidine and meperidine significantly reduced the incidence and the severity of shivering in comparison with placebo, whereas there were no significant differences between the urapidil and placebo groups. Both clonidine and meperidine caused a significantly prolonged emergence time (13.4 +/- 5.8 and 13. 3 +/- 5.0 min, respectively) compared with placebo (10.4 +/- 5.3 min) and urapidil (11.4 +/- 2.9 min). We confirmed that both clonidine and meperidine are effective in preventing postanesthetic shivering, whereas urapidil, in our setting and dosage, was not effective. Patients who received clonidine or meperidine had a prolonged emergence time. In the dosage used, urapidil seems to be unable to prevent postanesthetic shivering. IMPLICATIONS: Shivering (irregular muscle activity) is common after surgery and anesthesia. This study compared urapidil (an antihypertensive drug) as a prophylaxis with two established antishivering drugs (meperidine and clonidine) and placebo. In the dosage used, we were unable to show a significant benefit of urapidil.

Acute phase response to nitroprusside-induced controlled hypotension in patients undergoing radical prostatectomy.

This study evaluated the effects of sodium nitroprusside-induced controlled hypotension on the acute phase response in patients undergoing radical prostatectomy. Thirty patients were randomly allocated to two groups, a hypotension group (mean arterial blood pressure was adjusted to 50 mmHg) and a control group (mean arterial blood pressure > 70 mmHg). C-reactive protein increased significantly in the hypotension group from 0.13 (0.23) to 9.85 (2.84) microg x ml-1 and in the control group from 0.15 (0.27) to 7.38 (3.02) microg x ml-1. In both groups, serum amyloid A increased significantly, but levels were higher in the hypotension group [585 (125) microg x l-1] than in the control group [460 (187) microg x l-1]. Interleukin-6 increased significantly in both groups, but was higher in the hypotension group [139 (124) pg x ml-1] than the control group [56 (27) pg x ml-1]. Elastase showed no significant changes in the control group but in the hypotension group there was a significant increase from 65 (51) to 122 (75) ng x ml-1. Sodium nitroprusside-induced hypotension was associated with a more pronounced acute phase reaction.

Comparison of the effects of desflurane and isoflurane anaesthesia on hepatocellular function assessed by alpha glutathione S-transferase.

The purpose of this study was to investigate the influence of isoflurane and desflurane on hepatocellular function. Twenty male patients undergoing elective surgery were randomly assigned to receive either isoflurane or desflurane anaesthesia. Alpha glutathione S-transferase concentrations and aminotransferase activities were measured at induction of anaesthesia (t0), 15 min (t1), 90 min after induction (t2), end of surgery (t3) and 2 h thereafter (t4). A significant increase in alpha glutathione S-transferase concentration was observed only in the isoflurane group. Alpha glutathione S-transferase levels increased significantly from 2.3 microg.l-1 at t0 to 6.1 (1.9) microg.l-1 at t2 and to 7.8 (2.1) microg.l-1 at t3. A significant difference in alpha glutathione S-transferase concentration between the two groups was found at t2 and t3. The significant increases in alpha glutathione S-transferase concentrations in patients receiving isoflurane suggest a transient disturbance of hepatocellular function.

The effects of sodium nitroprusside-induced hypotension on splanchnic perfusion and hepatocellular integrity.

UNLABELLED: The purpose of our study was to investigate the effects of sodium nitroprusside-induced hypotension on splanchnic perfusion and hepatocellular integrity. Thirty patients undergoing radical prostatectomy were allocated randomly to a sodium nitroprusside (SNP) or control group (control). Regional pco2 was measured using gastric tonometry, and the regional to arterial difference in partial pressure of CO2 and intramucosal pH were calculated. The cytosolic liver enzyme alpha-glutathione S-transferase and standard liver enzyme markers (alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyltransferase) were also measured. Mean arterial pressure in the SNP group was 50 mm Hg for 97 min during surgery. A significant increase from baseline in regional pco2 (from 40.0+/-4.2 mm Hg to 45.3+/-1.3 mm Hg) and regional to arterial difference in partial pressure of CO2 (from 4.1+/-1.1 mm Hg to 9.7+/-1.4 mm Hg) was seen at 90 min after skin incision only in the SNP group. Intramucosal pH decreased significantly from 7.40+/-0.02 to 7.35+/-0.03 during the same period in this group. Tonometric variables returned to baseline values within 2 h postoperatively. Alpha-glutathione S-transferase concentrations increased significantly in the SNP group from baseline to peak concentrations at the end of surgery (SNP: 9.93+/-4.94 microg/L; control: 5.85+/-1.86 microg/L). A return to baseline values was seen 24 h postoperatively. No significant changes in standard liver enzyme markers were seen throughout the study period. It is concluded, that splanchnic perfusion was transiently impaired during controlled hypotension. This is supported by significant changes in tonometric data. Increased serum levels of alpha-glutathione S-transferase may indicate a disturbance in hepatocellular integrity. IMPLICATIONS: We studied gastric mucosal tonometry and the cytosolic liver enzyme alpha-glutathione S-transferase to evaluate the effects of controlled hypotension induced by sodium nitroprusside on splanchnic perfusion and hepatocellular integrity. Splanchnic perfusion decreased and alpha-glutathione S-transferase increased during and after a hypotensive period, but returned to baseline values within the first postoperative day, indicating a transient impairment of splanchnic perfusion and hepatocellular integrity.