Prevention of hypothermia in patients undergoing orthotopic liver transplantation using the humigard® open surgery humidification system: a prospective randomized pilot and feasibility clinical trial.

BACKGROUND: Perioperative thermal disturbances during orthotopic liver transplantation (OLT) are common. We hypothesized that in patients undergoing OLT the use of a humidified high flow CO2 warming system maintains higher intraoperative temperatures when compared to standardized multimodal strategies to maintain thermoregulatory homeostasis. METHODS: We performed a randomized pilot study in adult patients undergoing primary OLT. Participants were randomized to receive either open wound humidification with a high flow CO2 warming system in addition to standard care (Humidification group) or to standard care alone (Control group). The primary end point was nasopharyngeal core temperature measured 5 min immediately prior to reperfusion of the donor liver (Stage 3 - 5 min). Secondary endpoints included intraoperative PaCO2, minute ventilation and the use of vasoconstrictors. RESULTS: Eleven patients were randomized to each group. Both groups were similar for age, body mass index, MELD, SOFA and APACHE II scores, baseline temperature, and duration of surgery. Immediately prior to reperfusion (Stage 3 - 5 min) the mean (SD) core temperature was higher in the Humidification Group compared to the Control Group: 36.0 °C (0.13) vs. 35.4 °C (0.22), p = 0.028. Repeated measured ANOVA showed that core temperatures over time during the stages of the transplant were higher in the Humidification Group compared to the Control Group (p < 0.0001). There were no significant differences in the ETCO2, PaCO2, minute ventilation, or inotropic support. CONCLUSION: The humidified high flow CO2 warming system was superior to standardized multimodal strategies in maintaining normothermia in patients undergoing OLT. Use of the device was feasible and did not interfere with any aspects of surgery. A larger study is needed to investigate if the improved thermoregulation observed is associated with improved patient outcomes. TRIAL REGISTRATION: ACTRN12616001631493 . Retrospectively registered 25 November 2016.

Agreement in hemodynamic monitoring during orthotopic liver transplantation: a comparison of FloTrac/Vigileo at two monitoring sites with pulmonary artery catheter thermodilution.

To study agreement in cardiac index (CI), systemic vascular resistance index (Systemic VRI) and stroke volume variation (SV variation) between the FloTrac/Vigileo at radial and femoral arterial cannulation sites, and pulmonary artery catheter (PAC) thermodilution, in patients undergoing orthotopic liver transplantation. A prospective observational study of 25 adult patients with liver failure. Radial and femoral arteries were cannulated with standardised FloTrac/Vigileo arterial transducer kits and a PAC was inserted. CI, SV variation and Systemic VRI were measured four times (30 min after induction of anesthesia, 30 min after portal vein clamping, 30 min after graft reperfusion, 30 min after commencement of bile duct anastomosis). The bias, precision, limits of agreement (LOA) and percentage errors were calculated using Bland-Altman statistics to compare measurements from radial and femoral arterial cannulation sites and PAC thermodilution. Neither radial nor femoral CI achieved acceptable agreement with PAC CI [radial to PAC bias (SD) 1.17 (1.49) L/min/m2, percentage error 64.40 %], [femoral to PAC bias (SD) -0.71 (1.81) L/min/m2, percentage error 74.20 %]. Agreement between radial and femoral sites for CI [mean difference (SD) -0.43 (1.51) L/min/m2, percentage error 70.40 %] and Systemic VRI [mean difference (SD) 0.03 (4.17) LOA ±8.17 mmHg min m2/L] were also unacceptable. Agreement in SV variation between radial and femoral measurement sites approached a clinically acceptable threshold [mean difference (SD) 0.68 (2.44) %), LOA ±4.78 %]. FloTrac/Vigileo CI cannot substitute for PAC thermodilution CI, regardless of measurement site. SV variation measurements may be interchangeable between radial and femoral sites for determining fluid responsiveness.

The haemodynamic effects of intravenous paracetamol (acetaminophen) in healthy volunteers: a double-blind, randomized, triple crossover trial.

AIM: The haemodynamic effects of intravenous paracetamol have not been systematically investigated. We compared the physiological effects of intravenous mannitol-containing paracetamol, and an equivalent dosage of mannitol, and normal saline 0.9% in healthy volunteers. METHODS: We performed a blinded, triple crossover, randomized trial of 24 adult healthy volunteers. Participants received i.v. paracetamol (1 g paracetamol +3.91 g mannitol 100 ml(-1) ), i.v. mannitol (3.91 g mannitol 100 ml(-1) ) and i.v. normal saline (100 ml). Composite primary end points were changes in mean arterial pressure (MAP), systolic blood pressure (SBP) and diastolic blood pressure (DBP) measured pre-infusion, during a 15 min infusion period and over a 45 min observation period. Systemic vascular resistance index (SVRI) and cardiac index were measured at the same time points. RESULTS: Infusion of paracetamol induced a transient yet significant decrease in blood pressures from pre-infusion values (MAP -1.85 mmHg, 95% CI -2.6, -1.1, SBP -0.54 mmHg, 95% CI -1.7, 0.6 and DBP -1.92 mmHg, 95% CI -2.6, -1.2, P < 0.0001), associated with a transient reduction in SVRI and an increase in cardiac index. Changes were observed, but to a lesser extent with normal saline (MAP -0.15 mmHg, SBP +1.44 mmHg, DBP --0.73 mmHg, P < 0.0001), but not with mannitol (MAP +1.47 mmHg, SBP +4.03 mmHg, DBP +0.48 mmHg, P < 0.0001). CONCLUSIONS: I.v. paracetamol caused a transient decrease in blood pressure immediately after infusion. These effects were not seen with mannitol or normal saline. The physiological mechanism was consistent with vasodilatation. This study provides plausible physiological data in a healthy volunteer setting, supporting transient changes in haemodynamic variables with i.v. paracetamol and justifies controlled studies in the peri-operative and critical care setting.

Sodium bicarbonate infusion in patients undergoing orthotopic liver transplantation: a single center randomized controlled pilot trial.

BACKGROUND: Liver transplantation-associated acute kidney injury (AKI) carries significant morbidity and mortality. We hypothesized that sodium bicarbonate would reduce the incidence and/or severity of liver transplantation-associated AKI. METHODS: In this double-blinded pilot RCT, adult patients undergoing orthotopic liver transplantation were randomized to an infusion of either 8.4% sodium bicarbonate (0.5 mEq/kg/h for the first hour; 0.15 mEq/kg/h until completion of surgery); (n = 30) or 0.9% sodium chloride (n = 30). PRIMARY OUTCOME: AKI within the first 48 h post-operatively. RESULTS: There were no significant differences between the two treatment groups with regard to baseline characteristics, model for end-stage liver disease and acute physiology and chronic health evaluation (APACHE) II scores, and pre-transplantation renal function. Intra-operative factors were similar for duration of surgery, blood product requirements, crystalloid and colloid volumes infused and requirements for vasoactive therapy. Eleven patients (37%) in the bicarbonate group and 10 patients (33%) in the sodium chloride group developed a post-operative AKI (p = 0.79). Bicarbonate infusion attenuated the degree of immediate post-operative metabolic acidosis; however, this effect dissipated by 48 h. There were no significant differences in ventilation hours, ICU or hospital length of stay, or mortality. CONCLUSIONS: The intra-operative infusion of sodium bicarbonate did not decrease the incidence of AKI in patients following orthotopic liver transplantation.

The impact of fluid intervention on complications and length of hospital stay after pancreaticoduodenectomy (Whipple's procedure).

BACKGROUND: There is limited information on the impact on perioperative fluid intervention on complications and length of hospital stay following pancreaticoduodenectomy. Therefore, we conducted a detailed analysis of fluid intervention in patients undergoing pancreaticoduodenectomy at a university teaching hospital to test the hypothesis that a restrictive intravenous fluid regime and/or a neutral or negative cumulative fluid balance, would impact on perioperative complications and length of hospital stay. METHODS: We retrospectively obtained demographic, operative details, detailed fluid prescription, complications and outcomes data for 150 consecutive patients undergoing pancreaticoduodenectomy in a university teaching hospital. Prognostic predictors for length of hospital stay and complications were determined. RESULTS: One hundred and fifty consecutive patients undergoing pancreaticoduodenectomy were evaluated between 2006 and 2012. The majority of patients were, middle-aged, overweight and ASA class III. Postoperative complications were frequent and occurred in 86 patients (57%). The majority of complications were graded as Clavien-Dindo Class 2 and 3. Postoperative pancreatic fistula occurred in 13 patients (9%), and delayed gastric emptying occurred in 25 patients (17%). Other postoperative surgical complications included sepsis (22%), bile leak (4%), and postoperative bleeding (2%). Serious medical complications included pulmonary edema (6%), myocardial infarction (8%), cardiac arrhythmias (13%), respiratory failure (8%), and renal failure (7%). Patients with complications received a higher median volume of intravenous therapy and had higher cumulative positive fluid balances. Postoperative length of stay was significantly longer in patients with complications (median 25 days vs. 10 days; p < 0.001). After adjustment for covariates, a fluid balance of less than 1 litre on postoperative day 1 and surgeon caseloads were associated with the development of complications. CONCLUSIONS: In the context of pancreaticoduodenectomy, restrictive perioperative fluid intervention and negative cumulative fluid balance were associated with fewer complications and shorter length of hospital stay. These findings provide good opportunities to evaluate strategies aimed at improving perioperative care.

Size variation between contralateral infraclavicular axillary veins within individual patients-implications for subclavian venous central line insertion.

OBJECTIVE: Vein size and use of dynamic ultrasound guidance have been shown to be directly related to a reduction in insertion failure and complication rates during subclavian vein catheterization. We hypothesized that contralateral infraclavicular axillary vein sizes are significantly different within the same patient. We also aimed to demonstrate the relationship of subject's anthropomorphic indices with vein size and contralateral vein size difference. DESIGN: Prospective observational study. SETTING: Operating theatre of a tertiary hospital. PATIENTS: Fifty adult elective and emergency surgical patients. INTERVENTION: The largest dimensions of each patient's left and right infraclavicular axillary veins were measured with two-dimensional cross-sectional ultrasound examinations. The absolute difference between sides in individual patients was calculated using a paired difference t test and the relationship between hand dominance and vein size calculated by a paired difference t test of dominant side vein size minus nondominant side vein size MEASUREMENTS AND MAIN RESULTS: Forty-five patients (90%) of patients were right hand dominant. The mean proportional cross-sectional area difference between left and right sides in individual patients was 59.7% (SEM 9.2%), with absolute cross-sectional area difference of 26.7 mm (SEM 2.8 mm). All test statistics reached statistical significance at p < 0.0001. There was no relationship between right hand dominance and ipsilateral infraclavicular axillary vein size (p = 1.0), nor was there any clinically significant correlation between subject's anthropomorphic indices and ipsilateral infraclavicular axillary vein size or contralateral vein size difference (largest Pearson's r = 0.22). CONCLUSIONS: Contralateral infraclavicular axillary vein sizes within the same patient are significantly different in the adult surgical population and bear no clear relation to patient hand dominance. The magnitude of contralateral difference or absolute ipsilateral infraclavicular axillary vein size cannot be predicted by a subject's anthropomorphic indices. All patients in whom subclavian central line insertion is planned should have both sides examined by ultrasound to determine which side has the largest vessel.

Computerized tomographic anatomic relationships of the thoracic paravertebral space.

OBJECTIVES: A wide range of insertion points lateral to the midline are recommended for paravertebral blockade. The authors hypothesized that in a given subject, using an insertion point at the tip of the transverse process has a superficial but consistent depth to the pleura. The authors also hypothesized that for a given insertion point, depths to the pleura are related directly to the patient's anthropomorphic indices. DESIGN: Retrospective observational study. SETTING: Adult tertiary teaching hospital. PARTICIPANTS: Forty-two adult patients. INTERVENTIONS N/A MEASUREMENTS AND MAIN RESULTS: The authors reviewed the computerized tomography scans of 42 adult patients and correlated patients' body mass index, weight, height, and body surface area with skin and transverse process-to-pleura depths at the level of T4, 25 mm from the midline and from the tip of the transverse process. The authors found that the depth to the pleura from the transverse process was significantly deeper at 25 mm lateral to the midline than at the tip of the transverse process (21 mm [4.2mm] v 12 mm [2.7 mm], p<0.0001), and its variability was significantly larger (p = 0.005). The authors found significant correlation between anthropomorphic indices and depths to pleura and transverse process (r>0.8, p<0.0001); however, the prediction bands around their regression lines proved too broad to be clinically useful. CONCLUSIONS: The authors concluded that an insertion point at the tip of the transverse process may provide effective and safer paravertebral blockade and that depth to the pleura cannot be predicted reliably by patients' morphometric profiles.

Thromboelastography in elective total hip arthroplasty.

BACKGROUND: Hypercoagulability plays an important role in predisposing patients to venous thromboembolism (VTE) after total hip arthroplasty (THA). We used thromboelastography (TEG) to examine the coagulation status of patients undergoing THA. AIM: To examine coagulation as measured by TEG in patients undergoing THA who received standard VTE chemoprophylaxis with enoxaparin. METHODS: After ethical approval, we performed a retrospective analysis of data collected in patients undergoing primary elective THA. We analyzed TEG data on samples performed before skin incision, intraoperatively and for 5 d postoperatively. Conventional coagulation tests were performed preoperatively and on postoperative day 5. RESULTS: Twenty patients undergoing general anesthesia and 32 patients undergoing spinal anesthesia (SA) were included. TEG demonstrated a progressively hypercoagulable state postoperatively, characterized by elevated maximum amplitude. TEG also demonstrated transient intraoperative hypercoagulability in patients receiving SA. In contrast, conventional coagulation tests were normal in all patients, pre- and postoperatively, except for an increase in plasma fibrinogen day 5 postoperatively. CONCLUSION: Despite VTE prophylaxis, patients following total hip replacement remain in a hypercoagulable state as measured by both TEG and conventional tests. This group may benefit from more optimal anticoagulation and/or additional perioperative hemostatic monitoring, via TEG or otherwise.

Major complications related to the use of transesophageal echocardiography in cardiac surgery.

OBJECTIVE: The purpose of this study was to determine the incidence of injury associated with transesophageal echocardiography (TEE injuries) in cardiac surgery. DESIGN: Retrospective. SETTING: University-affiliated hospitals. PARTICIPANTS: Four thousand seven hundred eighty-four patients, 89% of all public hospital cardiac surgery patients in Victoria, from the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) database undergoing cardiac surgery with TEE between July 1, 2005, and June 30, 2007. Because ASCTS did not record TEE use before July 2005, it was assumed that 89% of an additional 11,719 cardiac surgery patients between July 2001 and June 2005 also had TEE. INTERVENTIONS: The authors searched the ASCTS database for cardiac surgery patients who also had endoscopy and/or noncardiac surgery. The files of these patients were screened for possible esophageal or gastric tears or perforations. An expert panel determined likely TEE injuries. MEASUREMENTS AND MAIN RESULTS: There were 6 TEE complications from July 1, 2005, to June 30, 2007 (13/10,000 patients). There were a further 8 TEE complications before June 30, 2005, an extrapolated overall rate of 9/10,000 TEE (95% confidence interval, 5-16/10,000). TEE complications were more frequent in patients more than 70 years old (relative risk [RR], 3.7; p = 0.03) and women (RR, 6.5; p < 0.001). Three patients with TEE injury died (2/10,000). CONCLUSIONS: TEE is associated with an incidence of major injuries of about 1 per 1,000 patients, with older women having a much higher risk. TEE use in cardiac surgery should be evaluated in the light of practice guidelines and morbidity and mortality data and not considered routine.

The effects of intravenous lignocaine on depth of anaesthesia and intraoperative haemodynamics during open radical prostatectomy.

BACKGROUND: Lignocaine is a local anaesthetic agent, which is also commonly used as a perioperative analgesic adjunct to accelerate rehabilitation and enhance recovery after surgery. Lignocaine's systemic effects on intraoperative haemodynamics and volatile anaesthetic requirements are not well explored. Therefore, we evaluated the effects of intravenous lignocaine on intraoperative volatile agent requirements and haemodynamics in patients undergoing major abdominal surgery. METHODS: We performed an analysis of 76 participants who underwent elective open radical retropubic prostatectomy. Patients received lignocaine (1.5 mg/kg loading dose) followed by an infusion (1.5 mg/kg/h) for the duration of surgery, or saline at an equivalent rate. The aims of the study were to evaluate the end-tidal sevoflurane concentration required to maintain a bispectral index of between 40 and 60. Measurements included intraoperative blood pressure, heart rate, and the volume of intravenous fluids and dosage of vasoactive medications administered. RESULTS: The average end-tidal sevoflurane concentration was lower in the Lignocaine group compared to saline [1.49% (SD: 0.32) vs. 1.89% (SD: 0.29); 95% CI 0.26-0.5, p < 0.001]. In the Lignocaine group, the average mean arterial pressure was 80.3 mmHg (SD: 4.9) compared to 85.1 mmHg (SD: 5.4) in the Saline group (95% CI 2.4-7.1, p < 0.001). Systolic blood pressure was also lower in the Lignocaine group: 121.7 mmHg (SD: 6.1) vs. 128.0 mmHg (SD: 6.4) in the Saline group; 95% CI 3.5-9.2, p < 0.001, as was the mean heart rate [Lignocaine group: 74.9 beats/min (SD: 1.8) vs. 81.5 beats/min (SD: 1.7) in the Saline group, 95% CI 4.1-9.1, p < 0.001]. Maintenance fluid requirements were higher in the Lignocaine group: 3281.1 mL (SD: 1094.6) vs. 2552.6 mL (SD: 1173.5) in the Saline group, 95% CI 206-1251, p = 0.007. There were no differences in the use of vasoactive drugs. CONCLUSIONS: Intravenous lignocaine reduces volatile anaesthetic requirements and lowers blood pressure and heart rate in patients undergoing open radical prostatectomy.

The effects on coagulation of the reinfusion of unprocessed residual blood from the cardiopulmonary bypass.

BACKGROUND: Autologous blood transfusion is a common technique in cardiac surgery to directly re-infuse residual blood from the cardiopulmonary bypass (CPB) circuit to the patient. The objective of this study was to evaluate the effects of reinfusion of unprocessed residual pump blood on the coagulation system after separation from the CPB circuit and reversal of systemic heparin with protamine. MEASUREMENTS AND MAIN RESULTS: After ethics approval, 40 participants undergoing cardiac surgery were recruited in a prospective single center cohort study. Changes in coagulation were assessed with standard plasma based laboratory assays and thromboelastography. After the reinfusion of unprocessed residual pump blood there were decreases in the mean aPTT (effect size 6 s; SD: 6.05; p < 0.0001) and thrombin time (effect size 4.08 s; SD: 9.7; p = 0.01). There were no significant changes in PT, INR and D-dimer. Post reinfusion there were increases in fibrinogen, hemoglobin and platelet counts. There were improvements in the R-time (effect size 9.1 s; SD: 16.9; p = 0.0023), K-time (effect size 1.5 s; SD: 3.6 s; p = 0.0017), alpha angle (6.9°; SD: 15.8; p = 0.012), and maximum amplitude (3.0 mm; SD: 5.6, p = 0.002) on thromboelastography. CONCLUSION: The reinfusion of unprocessed residual CPB blood resulted in no deleterious effects on the coagulation system measured by both the common laboratory plasma based measurements of coagulation and thromboelastography.

Perioperative blood management programme reduces the use of allogenic blood transfusion in patients undergoing total hip and knee arthroplasty.

BACKGROUND: Optimisation of blood management in total hip (THA) and knee arthroplasty (TKA) is associated with improved patient outcomes. This study aimed to establish the effectiveness of a perioperative blood management programme in improving postoperative haemoglobin (Hb) and reducing the rate of allogenic blood transfusion. METHODS: This retrospective before and after study involves 200 consecutive patients undergoing elective TKA and THA before (Usual Care group) and after (Intervention group) the introduction of a blood management programme in an Australian teaching hospital. Patients in the Intervention group underwent preoperative treatment for anaemia and received intraoperative tranexamic acid (15 mg/kg). The primary outcomes were to compare postoperative Hb levels and the rate of blood transfusion. Secondary outcomes included measurements of total amount of allogenic blood transfused, transfusion-related complications, postoperative complications, need for inpatient rehabilitation and duration of hospital stay. RESULTS: There were no differences between baseline characteristics between groups. The mean (SD) preoperative Hb was higher in the Intervention group compared to that in the Usual Care group: 138.7 (13.9) vs. 133.4 (13.9) g/L, p = 0.008, respectively. The postoperative day 1 Hb, lowest postoperative Hb and discharge Hb were all higher in the Intervention group (p < 0.001). Blood transfusion requirements were lower in the Intervention group compared to the Usual Care group (6 vs. 20 %, p = 0.003). There were no differences in any of the secondary outcomes measured. Patients who were anaemic preoperatively and who underwent Hb optimisation had higher Hb levels postoperatively (odds ratio 5.7; 95 % CI 1.3 to 26.5; p = 0.024). CONCLUSIONS: The introduction of a perioperative blood optimisation programme improved postoperative Hb levels and reduced the rate of allogenic blood transfusion.

Comparative Evaluation of Crystalloid Resuscitation Rate in a Human Model of Compensated Haemorrhagic Shock.

INTRODUCTION: The most effective rate of fluid resuscitation in haemorrhagic shock is unknown. METHODS: We performed a randomized crossover pilot study in a healthy volunteer model of compensated haemorrhagic shock. Following venesection of 15 mL/kg of blood, participants were randomized to 20 mL/kg of crystalloid over 10 min (FAST treatment) or 30 min (SLOW treatment). The primary end point was oxygen delivery (DO2). Secondary end points included pressure and flow-based haemodynamic variables, blood volume expansion, and clinical biochemistry. RESULTS: Nine normotensive healthy adult volunteers participated. No significant differences were observed in DO2 and biochemical variables between the SLOW and FAST groups. Blood volume was reduced by 16% following venesection, with a corresponding 5% reduction in cardiac index (CI) (P < 0.001). Immediately following resuscitation the increase in blood volume corresponded to 54% of the infused volume under FAST treatment and 69% of the infused volume under SLOW treatment (P = 0.03). This blood volume expansion attenuated with time to 24% and 25% of the infused volume 30 min postinfusion. During fluid resuscitation, blood pressure was higher under FAST treatment. However, CI paradoxically decreased in most participants during the resuscitation phase; a finding not observed under SLOW treatment. CONCLUSION: FAST or SLOW fluid resuscitation had no significant impact on DO2 between treatment groups. In both groups, changes in CI and blood pressure did not reflect the magnitude of intravascular blood volume deficit. Crystalloid resuscitation expanded intravascular blood volume by approximately 25%.

Agreement between radial and femoral arterial blood pressure measurements during orthotopic liver transplantation.

OBJECTIVE: To study agreement between radial and femoral arterial pressure measurements in orthotopic liver transplantation (OLTx) surgery to determine whether arterial cannulation sites are interchangeable. DESIGN, SETTING AND PARTICIPANTS: Prospective observational study of 25 patients undergoing OLTx surgery. METHODS: Radial and femoral arteries were cannulated with standardised arterial line kits. Radial and femoral mean arterial pressure (MAP), systolic arterial pressure (SAP), diastolic arterial pressure (DAP) and pulse pressure (PP) were measured at four time points (30 minutes after induction of anaesthesia, 30 minutes after the start of the anhepatic phase, 30 minutes after liver graft reperfusion and 30 minutes after the start of bile duct anastomosis). MAIN OUTCOME MEASURES: The bias, precision and limits of agreement between radial and femoral arterial pressures were calculated in accordance with Bland-Altman statistics. RESULTS: Radial-femoral differences in MAP (mean difference, 4.8 mmHg [SD, 4.5 mmHg]), limits of agreement (- 13.6 and 8.8, P < 0.001) and DAP showed clinically acceptable agreement between measurement sites across all time points. However, clinically significant differences between radial and femoral SAPs (mean difference, - 14.9 mmHg [SD, 24.8 mmHg]) and limits of agreement (- 63.5 and 33.7, P < 0.001) occurred overall. This difference started after portal vein clamping and remained significant throughout the remainder of the operation. CONCLUSION: Radial artery SAP underestimates femoral artery measurements significantly but unpredictably. As femoral measurement is more likely to reflect central arterial pressure, radial SAP measurement is not reliable in adults undergoing OLTx.

Haemostatic management for aortic valve replacement in a patient with advanced liver disease.

Redo-sternotomy and aortic valve replacement in patients with advanced liver disease is rare and associated with a prohibitive morbidity and mortality. Refractory coagulopathy is common and a consequence of intense activation of the coagulation system that can be triggered by contact of blood with the cardiopulmonary bypass circuitry, bypass-induced fibrinolysis, platelet activation and dysfunction, haemodilution, surgical trauma, hepatic decompensation and hypothermia. Management can be further complicated by right heart dysfunction, porto-pulmonary hypertension, poor myocardial protection, and hepato-renal syndrome. Complex interactions between coagulation/fibrinolysis and systemic inflammatory response syndrome reactions like "post-perfusion-syndrome" also compound haemostatic failure. Given the limited information available for the specific management and prevention of cardiopulmonary bypass-induced haemostatic failure, this report serves to guide the anaesthesia and medical management of future cases of a similar kind. We discuss our multimodal management of haemostatic failure using pharmacological strategies, thromboelastography, continuous cerebral and liver oximetry, and continuous cardiac output monitoring.

Fencl-Stewart analysis of acid-base changes immediately after liver transplantation.

OBJECTIVE: The Fencl-Stewart approach to acid-base physiology allows detailed, quantitative insights into acid-base disorders. We tested the hypothesis that this type of analysis would reveal complex acid-base changes in patients after liver transplantation that differed from those in a general intensive care unit population. METHODS: Data were collected retrospectively on patients on admission to the ICU after liver transplantation between 2001 and 2003 and prospectively on a convenience group of general ICU patients in 2001. RESULTS: Data were collected from 100 ICU patients and 83 liver transplant patients. Values for most clinical chemistry variables differed between the two groups, with considerable variation within the groups. All acid- base variables differed between the control and transplant groups (P < 0.005). Overall, the transplant group had metabolic acidosis (mean base excess +/-SD, -4.5 +/-3.1mmol/L) due to both a sodium chloride effect on base excess (-4.0 +/-4.1 mmol/L) and an other ion effect on base excess (-6.3 +/-4.2 mmol/L). The sodium chloride effect was mainly due to increased chloride concentration. All estimates of other anions (anion gap, corrected anion gap, strong ion gap, and the other ion effect on base excess) suggested that other anions play an important role in the acid-base status of patients after liver transplantation. These effects on base excess were partly offset by a greater metabolic alkalosis in the transplant group caused by a marked effect of decreased albumin on base excess (5.8 +/-1.5 mmol/L). CONCLUSIONS: The Fencl-Stewart approach allowed us to quantitatively assess the factors contributing to patients' acid-base status. We found complex acid-base changes in patients immediately after liver transplantation.

Postoperative complications and mortality in older patients having non-cardiac surgery at three Melbourne teaching hospitals.

OBJECTIVE: To determine the incidence of postoperative complications, including 30-day mortality rate, and need for intensive care unit (ICU) admission in older patients after non-cardiac surgery. DESIGN AND SETTING: Prospective observational study of all patients aged 70 years or older having elective and non-elective, non-cardiac surgery, and staying at least 1 night after surgery in one of three Melbourne teaching hospitals, June to September 2004. MAIN OUTCOME MEASURES: Postoperative complications and 30-day mortality rate. RESULTS: 1102 consecutive patients were audited in mid 2004; 70% had pre-existing comorbidities. The 30-day mortality rate was 6%; 19% had postoperative complications; and 20% of patients spent at least 1 night in ICU. On multivariate analysis, preoperative factors associated with 30-day mortality included age (odds ratio [OR], 1.09 per year over 70 years; 95% CI, 1.04-1.13; P < 0.001); increasing severity of systemic disease (American Society of Anesthesiologists physical status classification) (OR, 2.53; 95% CI, 1.65-3.86; P < 0.001); and albumin level < 30 g/L (OR, 2.23; 95% CI, 1.09-4.57; P = 0.03). Postoperative factors associated with 30-day mortality were unplanned ICU admission (OR, 3.95; 95% CI, 1.63-9.55; P = 0.003); sepsis (OR, 2.75; 95% CI, 1.17-6.47; P = 0.02); and acute renal impairment (OR, 2.40; 95% CI, 1.06-5.41; P = 0.04). Thoracic surgery was the only surgical specialty significantly associated with mortality (OR, 3.96; 95% CI, 1.44-9.10; P = 0.008) in the multivariate analysis. CONCLUSION: Older patients having surgery had high rates of comorbidities and postoperative complications, placing considerable demands on critical care services. Patient factors were often stronger predictors of mortality than the type of surgery.

Time to tracheal extubation after coronary artery surgery with isoflurane, sevoflurane, or target-controlled propofol anesthesia: a prospective, randomized, controlled trial.

OBJECTIVES: To determine if anesthesia with sevoflurane or target-controlled propofol reduced the time to tracheal extubation after coronary artery bypass graft surgery compared with isoflurane anesthesia. DESIGN: A 3-arm (isoflurane, sevoflurane, or propofol), randomized, controlled trial with patients and intensive care staff blinded to the drug allocation. SETTING: A single, tertiary referral hospital affiliated with the University of Melbourne. PARTICIPANTS: Three hundred sixty elective coronary artery surgery patients. INTERVENTIONS: Patients received either isoflurane (control group, 0.5%-2% end-tidal concentration), sevoflurane (1%-4% end-tidal concentration), or target-controlled infusion of propofol (1-8 microg/mL plasma target concentration) as part of a balanced, standardized anesthetic technique including 15 microg/kg of fentanyl. MEASUREMENTS AND MAIN RESULTS: The primary outcome was time to tracheal extubation. The median time to tracheal extubation for the propofol group was 10.25 hours (interquartile range [IQR] 8.08-12.75), the sevoflurane group 9.17 hours (IQR 6.25-11.25), and the isoflurane group 7.67 hours (IQR 6.25-9.42). Intraoperatively, the propofol group required less vasopressor (p = 0.002) and more vasodilator therapy (nitroglycerin p = 0.01, nitroprusside p = 0.002). There was no difference among the groups in time to intensive care unit discharge. CONCLUSIONS: The median time to tracheal extubation was significantly longer for the target-controlled propofol group. A significantly greater number in this group required the use of a vasodilator to control intraoperative hypertension.