Regulation of glucose kinetics during exercise by the glucagon-like peptide-1 receptor

In response to oral glucose, glucagon-like peptide-1 receptor (Glp1r) knockout (Glp1r−/−) mice become hyperglycaemic due to impaired insulin secretion. Exercise also induces hyperglycaemia in Glp1r−/− mice. In contrast to oral glucose, exercise decreases insulin secretion. This implies that exercise-induced hyperglycaemia in Glp1r−/− mice results from the loss of a non-insulinotropic effect mediated by the Glp1r. Muscle glucose uptake (MGU) is normal in exercising Glp1r−/− mice. Thus, we hypothesize that exercise-induced hyperglycaemia in Glp1r−/− mice is due to excessive hepatic glucose production (HGP). Wild-type (Glp1r+/+) and Glp1r−/− mice implanted with venous and arterial catheters underwent treadmill exercise or remained sedentary for 30 min. [3-3H]glucose was used to estimate rates of glucose appearance (Ra), an index of HGP, and disappearance (Rd). 2[14C]deoxyglucose was used to assess MGU. Glp1r−/− mice displayed exercise-induced hyperglycaemia due to an excessive increase in Ra but normal Rd and MGU. Exercise-induced glucagon levels were ∼2-fold higher in Glp1r−/− mice, resulting in a ∼2-fold higher glucagon:insulin ratio. Since inhibition of the central Glp1r stimulates HGP, we tested whether intracerebroventricular (ICV) infusion of the Glp1r antagonist exendin(9–39) (Ex9) in Glp1r+/+ mice would result in exercise-induced hyperglycaemia. ICV Ex9 did not enhance glucose levels or HGP during exercise, suggesting that glucoregulatory effects of Glp1 during exercise are mediated via the pancreatic Glp1r. In conclusion, functional disruption of the Glp1r results in exercise-induced hyperglycaemia associated with an excessive increase in glucagon secretion and HGP. These results suggest an essential role for basal Glp1r signalling in the suppression of alpha cell secretion during exercise.

Intraoperative anisocoria in a child during renal transplantation

Anisocoria during anaesthesia may indicate a serious neurological condition. Assessment by physical examination and diagnostic imaging is limited during surgery and anaesthesia. We report a case of a boy undergoing renal transplantation, who suffered from anisocoria during general anaesthesia. A transcranial sonography was performed, showing no intracranial pathology. However, retinal hypoperfusion detected with orbital doppler sonography was a plausible explanation for anisocoria.

HES 130/0.42 shows less alteration of pharmacokinetics than HES 200/0.5 when dosed repeatedly

BACKGROUND

Hydroxyethyl starches (HES) accumulate in the circulation when administered repeatedly. Accumulation is thought to be partly responsible for undesirable effects (tissue storage, blood coagulation impairment, and itching). HES 130/0.42 with low molecular weight and a low level of substitution has recently been developed in order to reduce those risks.

METHODS

In healthy volunteers, the pharmacokinetics of HES 130/0.42/6:1 were investigated using a crossover design with HES 200/0.5 serving as control. Fifty grams of either HES were administered in 4 h day-1 for a period of five consecutive days. HES serum concentrations were used for computation of pharmacokinetic coefficients. Change between the first and fifth infusion in the area under the concentration curve (AUC) served as the primary measurement.

RESULTS

Although the circulation was freed from the load with HES 130/0.42 within 20 h after end of the previous infusion, the amount of HES 200/0.5 increased continuously from one administration to the other. AUC and elimination half-life (t1/2) were significantly lower with HES 130/0.42. AUC and t1/2 of HES 200/0.5 showed an increase between the first and the fifth administration whereas only a minimal shift was present with HES 130/0.42. Haemodilution via HES 200/0.5 did not change over time.

CONCLUSIONS

Repeated administration of HES 130/0.42 shows no accumulation and fewer tendencies to time-dependent changes in pharmacokinetic parameters than HES 200/0.5. The improved reproducibility may improve drug safety, particularly as the accumulation of residual starch with HES 200/0.5 does not contribute to the colloid's volume effect, but may rather increase the risk of undesired reactions.

Effects of prophylactic or therapeutic application of bovine haemoglobin HBOC-200 on ischaemia-reperfusion injury following acute coronary ligature in rats

BACKGROUND

Haemoglobin-based oxygen carriers (HBOCs) are assessed as blood substitutes in patients with perioperative anaemia including patients at risk for perioperative cardiac ischaemia. There is controversy as to whether HBOCs are beneficial or deleterious during ischaemia-reperfusion (I-R). Therefore the effects of HBOC-200 on I-R injury were evaluated in a randomized placebo-controlled animal trial.

METHODS

Animals were randomized to receive either placebo i.v. without I-R (sham group, n=9), placebo i.v. with I-R (control group, n=10), HBOC-200 0.4 g kg(-1) i.v. prior to I-R (prophylaxis group, n=12) or HBOC-200 0.4 g kg(-1) i.v. during I-R (therapy group, n=15). I-R consisted of 25 min of acute ligature of the left coronary artery followed by 120 min of reperfusion. Measurements included assessment of the area at risk and infarct size using triphenyl tetrazolium chloride (TTC) stain, DNA single-strand breaks (in situ nick translation with autoradiography/densitometry) and cardiac arrhythmias.

RESULTS

Infarct size within the area at risk was 62 (sd 15)% (control), 46 (10)% (prophylaxis, P<0.025 vs control) and 61 (9)% (therapy, P<0.85 vs control). The frequency of DNA single-strand breaks was reduced vs control in the sham (P<0.01) and prophylaxis (P<0.04) groups and was almost the same in the therapy group (P<0.75). The severity of cardiac arrhythmias during ischaemia was lower compared with control in the sham (P<0.001) and prophylaxis (P<0.039) groups, but there was no difference in the therapy group.

CONCLUSION

This study demonstrates that neither prophylactic nor therapeutic application of the cell-free haemoglobin solution HBOC-200 aggravates cardiac I-R injury. Furthermore, the prophylactic approach may offer a new opportunity for pretreatment of patients at risk for perioperative ischaemic cardiac events.

Effects of isovolaemic haemodilution on oxygenation of liver and skeletal muscle

BACKGROUND AND OBJECTIVE

Hydroxyethyl starch is frequently used for volume substitution during surgical procedures and for isovolaemic haemodilution. Haemodilution has also been shown to improve tissue oxygen tension in skeletal muscle: However, effects of this volume substitute on tissue oxygen tension of the liver during haemodilution remains unknown.

METHODS

Fourteen foxhounds were anaesthetized with fentanyl/midazolam and mechanically ventilated with 30% oxygen. Following splenectomy animals were randomly assigned to a control group without haemodilution but fluid substitution with Ringer's lactate (Group C) or underwent isovolaemic haemodilution to a haematocrit of 25% with hydroxyethyl starch 70/0.5 (Group H). Haemodynamic parameters and oxygen transport during 100 min following isovolaemic haemodilution were measured. Liver oxygen tension was recorded using a flexible polarographic electrode tonometer, whereas in the muscle a polarographic needle probe was used.

RESULTS

Animal characteristics and baseline haematocrit were similar in both groups. At baseline the tissue oxygen tension of liver and skeletal muscle were not different between groups. Haemodilution with hydroxyethyl starch 70/0.5 provided augmentation of mean liver tissue oxygen tension (baseline: 46 +/- 13 mmHg; 20 min: 60.3 +/- 12 mmHg; 60 min: 60 +/- 16 mmHg; 100 min: 63 +/- 16 mmHg; P < 0.05 vs. baseline), while oxygen tensions in Group C remained unchanged (baseline: 48 +/- 16 mmHg; 20 min: 52 +/- 19 mmHg; 60 min: 49 +/- 12 mmHg; 100 min: 52 +/- 16 mmHg) and no differences could be detected between groups. Oxygen tension in skeletal muscle changed as follows: Group H - baseline: 24 +/- 32 mmHg; 20 min: 32 +/- 3 mmHg; 60 min: 33 +/- 7 mmHg; 100 min: 33 +/- 11 mmHg. Group C - baseline: 22 +/- 6 mmHg; 20 min: 21 +/- 3 mmHg; 60 min: 24 +/- 4 mmHg; 100 min: 18 +/- 4 mmHg (P < 0.05 vs. baseline, p < 0.05 vs. Group C).

CONCLUSION

In this animal model, isovolaemic haemodilution with hydroxyethyl starch 70/0.5 increased tissue oxygen tension in liver and skeletal muscle in comparison with baseline values. However, when compared between groups haemodilution only resulted in an increase of tissue oxygen tension in the muscle but not in the liver.

Hemoglobin-based oxygen carrier HBOC-201 provides higher and faster increase in oxygen tension in skeletal muscle of anemic dogs than do stored red blood cells

BACKGROUND

Increasing need for and potential shortage of blood products have intensified the search for alternative oxygen carriers. A solution to this problem could be use of the bovine hemoglobin-based oxygen carrier HBOC-201. While hemodynamic reactions to cell-free hemoglobin have been studied, little knowledge exists about tissue oxygenation properties of hemoglobin solutions, especially in comparison with red blood cells (RBCs).

STUDY DESIGN AND METHODS

Tissue oxygenation in skeletal muscle of 12 anesthetized dogs was examined after decrease of hemoglobin concentrations by means of hemodilution to hematocrit 10% and subsequent transfusion with either HBOC-201 or autologous banked RBCs. In addition to hemodynamic parameters, blood gas concentrations and oxygen content in arterial and muscular venous blood, tissue oxygen tension (tPO(2)) were measured in the gastrocnemius muscle with a polarographic needle probe.

RESULTS

Hemodilution increased muscular blood flow and oxygen extraction and decreased tPO(2). Transfusion decreased muscular oxygen extraction in the RBC group but not in the HBOC-201 group (P <.01). The 10th percentile of tPO(2) increased by 400% after the first dose of HBOC-201 (P <.001 vs posthemodilution) but only by 33% after equivalent RBC transfusion (P <.01 vs HBOC-201). Increases in the 50th (120%, P <.05) and 90th (31%) percentiles and all percentiles of tPO(2) after the second and third HBOC-201 dose were less pronounced but higher than in the RBC group.

CONCLUSION

Compared with RBC transfusion, infusion of low doses of HBOC-201 maintain enhanced oxygen extraction after extended hemodilution and provide faster and higher increase in muscular tissue PO(2).

Dolasetron prophylaxis reduces nausea and postanaesthesia recovery time after remifentanil infusion during monitored anaesthesia care for extracorporeal shock wave lithotripsy

BACKGROUND

Remifentanil is used as an analgesic for different procedures performed during monitored anaesthesia care. Opioid-induced nausea and vomiting can be troublesome.

METHODS

This prospective, randomized, double-blind study was performed to evaluate the efficacy of prophylaxis with dolasetron in reducing the frequency of postoperative nausea and duration of discharge time. Forty urological patients, undergoing elective ambulatory extracorporeal shock wave lithotripsy (ESWL) received randomly either dolasetron 12.5 mg i.v. (Group 1) or placebo (Group 2) 10 min before a patient-adapted continuous infusion of remifentanil 0.15-0.4 micro g kg(-1) min(-1) was administered. Frequency and intensity (VAS 0-100 mm) of nausea, retching, and vomiting were assessed by patients and blinded investigators during and after the procedure.

RESULTS

Patient characteristics, baseline values, duration of ESWL, and total dose of remifentanil did not differ between groups. The frequency (Group 1/Group 2; 20/55%; P<0.05) and mean (SD) maximal intensity [15 (9)/45 (14) mm; P<0.05] of nausea during 24 h was significantly reduced after dolasetron and discharge times in Group 1 were less than Group 2 [22 (14)/45 (28) min; P<0.05].

[Rupture of the trachea after emergency endotracheal intubation]

The rupture of the trachea is a rare but serious complication after endotracheal intubation. We report the case of a 77-year-old severely diseased woman with emergency intubation after development of acute respiratory distress. Four days after the emergency intubation a laceration of the membraneous part of the trachea was diagnosed. The patients general condition and the infaust prognosis resulted in the lack of therapeutic options and the death of the patient. According to the forensic autopsy the secondary perforation is probably a consequence of intubation or a pressure lesion of the tube in combination with a weakness of the membraneous part of the trachea due to impaired microperfusion. Every physician performing an intubation has to be aware of the risk and the consequences of a tracheal rupture.

A comparison of anaesthetic techniques for shock wave lithotripsy: the use of a remifentanil infusion alone compared to intermittent fentanyl boluses combined with a low dose propofol infusion

This study examined the intra-operative and postoperative characteristics of a remifentanil infusion alone, or intermittent fentanyl bolus admistration combined with a propofol infusion, for the anaesthetic management of patients undergoing shock wave lithotripsy. One of the key parameters investigated was the time to discharge. Fifty patients scheduled for extracorporeal shock wavelithotripsy (ESWL) were randomly allocated to receive either a continuous infusion of 0.2-0.4 micro g.kg-1.min-1 of remifentanil (Group 1) or a bolus of 3 micro g.kg-1 fentanyl followed by a continuous infusion of propofol at a rate of 2 mg.kg-1.h-1 with additional boluses of 0.05 mg fentanyl administered as required (Group 2). Both anaesthetic techniques were found to provide satisfactory analgesia and intra-operative conditions for ESWL. However, patients in the remifentanil Group 1 showed a higher incidence of nausea (52% vs. 0%, p < 0.01) and retching (36% vs. 0%, p < 0.01) 120 min following ESWL compared to Group 2. This resulted in prolonged discharge times (p < 0.01) in this group. We found that remifentanil used as the sole agent failed to demonstrate any advantage over the combination of fentanyl/propofol with regard to rapid recovery and discharge following anaesthesia for extracorporal shock wave lithotripsy.

[Severe mediastinal emphysema after temporal gunshot with a gas revolver]

Injuries after a close contact gunshot with clear or tear gas cartridges can lead to severe and life threatening complications. The high pressure of the gas may damage soft tissue, bones and organs. This mechanism is able to cause mediastinal emphysema, rupture of upper and lower pharyngeal, esophageal and tracheal structures far away from the initial trauma with diagnostic findings which are may be difficult to interpret. This case report presents a mediastinal emphysema in a 17 year old man following a temporal shot with a gas revolver. The diagnostics, focussed on CT and X-ray imaging, and the therapeutic concept of such cases will be discussed.

[Ropivacaine 0.2% versus bupivacaine 0.125% plus sufentanil for continuous peridural analgesia following extended abdominal operations]

OBJECTIVE

An improved opioid-free analgesia concept using thoracic epidural anlgesia with a low concentrated local anaesthetic alone could be of practical interest for hospitals which are unable to guarantee continuous monitoring on the wards.

METHODS

We have compared in a prospective, randomized, double-blind study, the analgesic effects and side effects of ropivacaine 0.2% (Group 1) with bupivacaine 0.125% plus 0.5 microgram ml-1 sufentanil (Group 2) via a thoracic epidural catheter during the first 24 hours after major abdominal surgery in 28 gynaecological tumour patients. Assessments were performed 8, 12, 16, 20 and 24 hours after surgery.

RESULTS

No differences were seen in duration of surgery, intraoperative opioid and supplemental analgesic requirements. As a main result VAS values for pain during mobilisation were higher in Group 1 when compared with Group 2 (p < 0.01) after 20 and 24 hours of continuous epidural infusion (10 ml h-1) whereas VAS values at rest were comparable (p < 0.1) at all measurepoints. Intensity of motor block and side effects did not differ between groups.

CONCLUSION

The present study shows that continuous epidural infusion of 0.2% ropivacaine alone provides comparable analgesia at rest, but less profound pain relief during mobilisation within the first 24 hours after major abdominal surgery than bupivacaine 0.125% with sufentanil.

Organization and neurochemistry of vagal preganglionic neurons innervating the lower esophageal sphincter in ferrets

The motor control of the lower esophageal sphincter (LES) is critical for normal swallowing and emesis, as well as for the prevention of gastroesophageal reflux. However, there are surprisingly few data on the central organization and neurochemistry of LES-projecting preganglionic neurons. There are no such data in ferrets, which are increasingly being used to study LES relaxation. Therefore, we determined the location of preganglionic neurons innervating the ferret LES, with special attention to their relationship with gastric fundus-projecting neurons. The neurochemistry of LES-projecting neurons was also investigated using two markers of "nontraditional" neurotransmitters in vagal preganglionic neurons, nitric oxide synthase (NOS), and dopamine (tyrosine hydroxylase: TH). Injection of cholera toxin B subunit (CTB)-horseradish peroxidase (HRP) into the muscular wall of the LES-labeled profiles throughout the rostrocaudal extent of the dorsal motor nucleus of the vagus (DMN) The relative numbers of profiles in three regions of the DMN from caudal to rostral are, 43 +/- 5, 67 +/- 11, and 113 +/- 30). A similar rostrocaudal distribution occurred after injection into the gastric fundus. When CTB conjugated with different fluorescent tags was injected into the LES and fundus both labels were noted in 56 +/- 3% of LES-labeled profiles overall. This finding suggests an extensive coinnervation of both regions by vagal motor neurons. There were significantly fewer LES-labeled profiles that innervated the antrum (16 +/- 9%). In the rostral DMN, 15 +/- 4% of LES-projecting neurons also contained NADPH-diaphorase activity; however, TH immunoreactivity was never identified in LES-projecting neurons. This finding suggests that NO, but not catecholamine (probably dopamine), is synthesized by a population of LES-projecting neurons. We conclude that there are striking similarities between LES- and fundic-projecting preganglionic neurons in terms of their organization in the DMN, presence of NOS activity and absence of TH immunoreactivity. Coinnervation of the LES and gastric fundus is logical, because the LES has similar functions to the fundus, which relaxes to accommodate food during ingestion and preceding emesis, but has quite different functions from the antrum, which provides mixing and propulsion of contents for gastric emptying. The presence of NOS in some LES-projecting neurons may contribute to LES relaxation, as it does in the case of fundic relaxation. The neurologic linkage of vagal fundic and LES relaxation may have clinical relevance, because it helps explain why motor disorders of the LES and fundus frequently occur together.

Fast-track regional anaesthesia

Regional anaesthesia plays an important role in day case surgery because it combines reliable effects with low risk and the possibility of local postoperative analgesia without systemic side-effects. Fast-track regional anaesthesia allows short-term postoperative surveillance or even bypassing the post-anaesthesia care unit. Peripheral nerve blocks provide long-lasting pain relief, and can accelerate timely discharge if a persisting motor block is accepted. Multiple peripheral nerve stimulation and injection techniques may help to realize differential blockades with a pronounced analgesic rather than a motor blocking effect. Nerve blocks with local anaesthetics in combination with alpha2-adrenoceptor agonists or non-steroidal anti-inflammatory drugs and short-acting parenteral opioids represent an effective multimodal concept for ambulatory surgery.

[Symptomatic tachyarrhythmia in patients with a cardiac pacemaker in emergency situations]

Symptomatic tachyarrhythmia in the presence of a cardiac pacemaker is challenging in preclinical emergency situations. This article presents a case report and a diagnostic and therapeutic concept for prehospital treatment of such cases. The usefulness of extracorporeal magnet application which is recommended in the literature and the possibilities of antiarrhythmic therapy will be critically discussed.

[Is spinal anesthesia for operations in the prone or jackknife position suitable?]

There is still controversy on the usefulness of spinal anesthesia for operations performed in the prone or jackknife position. There is about the risk of inadvertent increase of the sensomotory blockade with the patient in the prone position and the difficulty of managing consecutive cardiorespiratory complications or inducing general anesthesia in case of failures. This article reviews the current literature in terms of safety and effectiveness of spinal anesthesia for such operations. For lower-limb or perianal operations with limited extension and blood loss, performed in the prone position, spinal anesthesia seems to be a safe, effective and economic technique in patients without severe a cardiac history. Substantial knowledge about the onset time, fixation time, duration of sensomotory block and baricity of the applied local anesthetic is crucial in this setting. Obese patients are at risk for sudden extension of the block when turned into the prone position. Additional narcotics and sedatives should be avoided and continuous monitoring of hemodynamic and respiratory parameters, of the level of the blockade and vigilance of the patient is mandatory.

Transcranial Doppler sonography mean flow velocity during infusion of ultrapurified bovine hemoglobin

A number of studies have shown that polymerized bovine hemoglobin (HBOC-201) does not cause clinically significant side effects. This has been demonstrated in spite of the fact that a primary increase in oxygen extraction ratio has been associated with an increase in systemic vascular resistance (SVR) and a decrease in cardiac index (CI). The current study investigated the effects of HBOC-201 on cerebral circulation. Middle cerebral artery mean flow velocity (Vm) was measured using Transcranial Doppler sonography. After institutional review board approval and informed consent were obtained, 12 patients (mean age 59+/-10 years), scheduled for hepatic resection, were enrolled. Anesthesia during the induction period consisted of etomidate (0.3 mg/kg), fentanyl (3 mcg/kg), and vecuronium (0.1 mg/kg). Anesthesia during the maintenance period consisted of isoflurane (0.64-0.8 vol%)/O2/N2O (FiO2=0.3), fentanyl, and vecuronium. End-tidal carbon dioxide partial pressure (PetCO2), arterial carbon dioxide partial pressure (PaCO2), mean arterial blood pressure (MAP), CI, SVR, mean flow velocity, and pulsatility index were measured in each patient. Hemodilution was performed in all patients, followed by randomized assignment to two groups: Group 1 (n=6) received 0.4 g/kg HBOC-201, Group 2 (n=6) received a corresponding volume of hydroxyethyl starch (mw 70,000). Measurements were taken at six points (PMs): before hemodilution (PM 1); following hemodilution (PM2); and at 3, 10, 20, and 30 minutes (PM 3-6) after infusion of HBOC-201 or starch. Systemic vascular resistance rose in Group 1 as compared with Group 2, with significant differences at PM 3-6. The greatest difference was at PM 6 (Group 2=1071 dyne x s x cm(-5); Group 1=2154 dyne x s x cm(-5)). Cardiac indices were significantly lower in Group 1 (1.7-1.8 l/minute x m(-2)) than in Group 2 (2.4-2.7 l/minute x m(-2)) after PM 3. After hemodilution, mean flow velocity showed an insignificant increase in both groups, ranging from 39 to 46 cm/second. Although SVR increased significantly following HBOC-201 -infusion, the results of this study did not reveal changes in cerebral blood flow that establish significant group-to-group differences.

Safety and efficacy of spinal vs general anaesthesia in bone marrow harvesting

Bone marrow harvesting (BMH) can be performed with either general (GA) or spinal anaesthesia (SPA). Whether SPA is advantageous in BMH and if this technique is safe for procedures performed in the prone position is still controversial. To evaluate the safety and efficacy of both anaesthetic techniques in BMH, 37 allogeneic donors (nine female, 28 male; 34.3 +/- 9 years; ASA class 1-2) received either spinal (group 1, n =20) or general anaesthesia (group 2, n = 17) according to their personal wishes. Under standardised harvesting conditions, haematology parameters, cell counts (MNC, CD34+), haemodynamic parameters, adverse reactions and patient satisfaction were registered. No differences were seen between groups with respect to demographic data, harvesting time (55 +/- 17 vs 60 +/- 16 min) and bone marrow cell counts (MNC: 6.68 +/- 2.1 vs 5.7 +/- 1.7 ml/10(6)). The incidence of hypotension was higher in group 1 (45 vs 10.8%; P =0.042). Postoperative analgesic requirement and emesis were increased in group 2 (P < 0.04) in comparison to group 1. In conclusion, the present study failed to show superiority of spinal over general anaesthesia with regard to the quality of the harvested bone marrow. However, the lower incidence of complaints after spinal anaesthesia appears to offer an advantage over GA in healthy allogeneic bone marrow donors.

Bovine haemoglobin-based oxygen carrier for patients undergoing haemodilution before liver resection

We have studied the use of ultrapurified polymerized bovine haemoglobin (HBOC-201) in patients undergoing preoperative haemodilution before liver resection. After autologous blood donation of 1 litre, 12 patients (six males, six females, mean age 59 (35-69) yr) received Ringer's lactate solution 2 litre and, in a random design, 6% hydroxyethyl starch 70,000/0.5 (HES) 3 ml kg-1 or HBOC-201 0.4 g kg-1 within 30 min. Blood samples were obtained for blood chemistry, co-oximetry, haematology, coagulation profiles and immunology examinations before operation, on the day of surgery, on days 2-4 and 7 after operation, on the discharge day and 3 months after operation. There were no differences in patient characteristics, blood loss, amount of solutions infused, transfused allogeneic blood or duration of hospital stay. There were no local or systemic allergic reactions with infusion of HES or HBOC-201. Patients receiving HBOC-201 developed more pronounced leucocytosis and reticulocytosis during the early postoperative days compared with HES-treated patients. The mean maximum plasma haemoglobin concentration was 1.0 (SD 0.2) g dl-1 at the end of infusion of HBOC-201 was 8.5 h. Patients in both groups experienced temporary changes in liver enzymes and coagulation variables which returned to normal before discharge. Urinalysis revealed no difference between groups and no free haemoglobin was detected in urine. Patients receiving HBOC-201 showed no IgE and only a slight increase in IgG titres to HBOC-201 on the day of discharge; these were not detectable at 3 months. Single-dose administration of HBOC-201 was well tolerated by patients undergoing elective liver resection surgery and appears to be safe as a substitute during preoperative haemodilution.