Brian M. Parker

Use of tissue plasminogen activator in liver transplantation from donation after cardiac death donors.

Ischemic‐type biliary stricture (ITBS) occurs in up to 50% after liver transplantation (LT) from donation after cardiac death (DCD) donors. Thrombus formation in the peribiliary microcirculation is a postulated mechanism. The aim was to describe our experience of tissue plasminogen activator (TPA) administration in DCD‐LT. TPA was injected into the donor hepatic artery on the backtable (n = 22). Two recipients developed ITBS including one graft failure. Although excessive postreperfusion bleeding was seen in 14 recipients, the amount of TPA was comparable between those with and without excessive bleeding (6.4 ± 2.8 vs. 6.6 ± 2.8 mg, p = 0.78). However, donor age (41 ± 12 vs. 29 ± 9 years, p = 0.02), donor BMI (26.3 ± 5.5 vs. 21.7 ± 3.6 kg/m2, p = 0.03), previous laparotomy (50% vs. 0%, p = 0.02) and lactate after portal reperfusion (6.3 ± 4.6 vs. 2.8 ± 0.9 mmol/L, p = 0.005) were significantly greater in recipients with excessive bleeding. In conclusion, the use of TPA may lower the risk of ITBS‐related graft failure in DCD‐LT. Excessive bleeding may be related to poor graft quality and previous laparotomy rather than the amount of TPA. Further studies are needed in larger population.

Redefining the preoperative evaluation process and the role of the anesthesiologist

STUDY OBJECTIVE To assess the effects of implementing an ambulatory and same-day surgery preoperative evaluation patient triage system over a 3-year period. DESIGN Retrospective analysis of 63,941 ambulatory surgical patients presenting for elective surgery. SETTING Tertiary care, academic medical institution. INTERVENTIONS The following preoperative evaluation model components were implemented over a 3-year period: HealthQuest, which is an outpatient preoperative assessment computer program developed by the Department of General Anesthesiology; a general internal medicine clinic designated specifically for preoperative evaluation and medical optimization; disease specific algorithms for both preoperative patient assessment and management; and a preoperative anesthesia clinic that no longer performs preoperative medical optimization. MEASUREMENTS AND MAIN RESULTS During the 3-year study period ambulatory and same-day surgical case volume increased 34.7%. A total of 50,967 patients used HealthQuest as part of their preoperative evaluation. Of these patients 22,744 (35.6%) did not need to see an anesthesiologist until the day of surgery as guided by both a computer-assigned HealthQuest score and surgical classification scheme. Also, 41,197 patients were evaluated in our anesthesia preoperative clinic with a cost per evaluation of

Six sigma methodology can be used to improve adherence for antibiotic prophylaxis in patients undergoing noncardiac surgery.

24.86, which increased only 0.9% per year. In addition, both patient interview time and patient dissatisfaction with the preoperative process decreased over the 3-year period. There were 20, 088 patient encounters in the general internal medicine clinic for patient medical evaluation and optimization. The average monthly preoperative surgical delay rate decreased 49% during the study period. Finally, significant monetary saving resulted due to decreased unnecessary laboratory testing. CONCLUSIONS Efficient, cost-effective patient care can be provided by using this preoperative evaluation model. Some institutions may find portions of this preoperative model applicable to their current situation.

A comparison of postoperative pain control in patients after right lobe donor hepatectomy and major hepatic resection for tumor

BACKGROUND:Six Sigma methodology is a data management process that can be used to achieve a goal of near perfection in process performance. An audit of 615 surgeries over 2 mo revealed only 38% of noncardiac patients admitted on the day of surgery at our institution received perioperative antimicrobial prophylaxis within the target interval of ≤60 min before incision. METHODS:Six Sigma methodology was used to improve our process of timing of antimicrobial prophylaxis administration. A multidisciplinary team was assembled which identified seven process inputs by which patients receive antimicrobial prophylaxis. Interventions for improvement included reinforcement of use of preoperative antibiotic order forms, eliminating administration of antibiotics in the preoperative admission area, and sending appropriate antibiotics and IV tubing with the patient to the operating room. We concurrently developed a control plan to sustain this improvement using a recently deployed electronic anesthesia record keeping system using real-time measurement and reporting capabilities of antimicrobial prophylaxis administration. After defining the new process and undertaking a system-wide educational effort, implementation was begun with data collection and analysis occurring over the next 7 mo. RESULTS:For the 8-mo postintervention interval, there was a significant improvement with 86% of 1716 surgical patients receiving their antibiotic prophylaxis within the specified time frame (P < 0.01). The time interval for antibiotic administration before surgical incision also decreased from a preintervention mean of 88 (CI 56–119 min) to 38 min (CI 25–51 min) (P < 0.01). CONCLUSION:We conclude that Six Sigma methods were used to successfully improve our process for timing of perioperative antibiotic prophylaxis before surgical incision. An electronic anesthesia record keeping system is a useful tool to monitor this process improvement.

Association between donor‐recipient serum sodium differences and orthotopic liver transplant graft function

After initiating a living donor liver transplant program at our institution, we observed that donor patients experienced significant postoperative pain despite the use of thoracic patient-controlled epidural analgesia (PCEA) infusion catheters. We retrospectively compared patients who underwent right lobe donor hepatectomy (RLDH, n = 15) with patients who had undergone major hepatic resection for tumor (MHRT, n = 15) to elucidate the cause for this observation. All patients had preoperative thoracic epidural catheters placed, and both groups had similar surgical exposure. Demographic information, intraoperative variables, intensity of postoperative pain by visual analog pain score (VAPS), side effects, total number of requested and delivered PCEA doses, and the total amount of bupivacaine (mg) and volume (mL) of PCEA solution administered through 48 h postoperatively were collected and analyzed. The RLDH group had a significantly longer surgical duration than did the MHRT group. The RLDH group patients had higher postoperative pain scores (P = 0.034), and were 2.76 (1.12–6.82, 95% CI) times more likely to have pain than those patients in the MHRT group. There was no significant difference between patient groups for the amount of bupivacaine and volume of PCEA solution administered. These observations may be explained, in part, by the longer duration of surgery in the RLDH group. The possible role of preemptive analgesia via PCEA infusion and better perioperative teaching of PCEA use are discussed; these may lead to improved early postoperative pain control in RLDH patients.

Dynamic left ventricular outflow tract obstruction in an orthotopic liver transplant recipient

Previous studies have shown that donor hypernatremia and possibly recipient hyponatremia negatively impact graft function after orthotopic liver transplant (OLT). The purpose of this retrospective investigation was to determine whether measured differences in serum sodium values between cadaveric donors and OLT recipients (ΔNa+) influence immediate postoperative allograft function and short‐term patient outcomes. Two hundred and fifty patients that underwent OLT from January 2001 to December 2005 were included in this study. The ΔNa+ for each donor recipient pair was correlated with standard postoperative liver function tests as well as recipient length of intensive care unit stay (LOICUS), length of hospital stay (LOHS) and recipient survival. The relationship between donor hypernatremia (serum sodium ≥ 155 mEq/mL), recipient hyponatremia (serum sodium level ≤ 130 mEq/mL), and postoperative outcomes were analyzed as well. Adjustments were made for baseline potential confounders, including model for end‐stage liver disease (MELD) score, preservation solution used (HTK vs. UW), recipient and donor demographics and cold ischemia time (CIT). ΔNa+ as well as donor hypernatremia and recipient hyponatremia were not found to be associated with immediate postoperative allograft function, intraoperative blood product usage, LOICUS, LOHS or short‐term patient survival. However, both the preoperative MELD score and HTK preservation solution used were significantly associated with several patient outcomes. A higher MELD score was associated with both increased red blood cell (RBC) (P < 0.001) and fresh frozen plasma (FFP) usage (P = 0.002), elevated postoperative total bilirubin levels (P < 0.001), increased LOHS (P = 0.04), and a higher 30‐day post transplant mortality (P = 0.02). The use of HTK preservation solution was associated with higher mean postoperative aspartate aminotransferase levels (P = 0.02) and decreased mean RBC (P < 0.001) and FFP usage (P = 0.009) compared to UW preservation solution use. Liver Transpl 14:59–65, 2008.

Circulating-water garment or the combination of a circulating-water mattress and forced-air cover to maintain core temperature during major upper-abdominal surgery

A 53 year‐old man with Laennecs and hepatitis C–related cirrhosis was found to have dynamic left ventricular outflow tract obstruction during routine evaluation for orthotopic liver transplantation. The outflow tract obstruction gradient was quantified as being 155 to 189 mmHg maximally during dobutamine stress echocardiography. The patient subsequently underwent successful orthotopic liver transplantation at our institution. We discuss here the use of intraoperative transesophageal echocardiography to detect early signs of dynamic outflow tract obstruction and provide a rational guide for fluid and hemodynamic management. We conclude that the measured pressure across the left ventricular outflow tract during dobutamine stress testing does not necessarily predict either intraoperative hemodynamic perturbations such as obstruction or outcome in these patients. (Liver Transpl 2005;11:692–695.)

Transfusion of older red blood cells is associated with decreased graft survival after orthotopic liver transplantation.

BACKGROUND A recent heat-balance study in volunteers suggested that greater efficacy of circulating-water garments (CWGs) results largely from increased heat transfer across the posterior skin surface since heat transfer across the anterior skin surface was similar with circulating-water and forced-air. We thus tested the hypothesis that the combination of a circulating-water mattress (CWM) and forced-air warming prevents core temperature reduction during major abdominal surgery no worse than a CWG does. METHODS Fifty adult patients aged between 18 and 85 yr old, undergoing major abdominal surgery, were randomly assigned to intraoperative warming with a combination of forced-air and a CWM or with a CWG (Allon ThermoWrap). Core temperature was measured in the distal oesophagus. Non-inferiority of the CWM to the CWG on change from baseline to median intraoperative temperature was assessed using a one-tailed Students t-test with an equivalency buffer of -0.5°C. RESULTS Data analysis was restricted to 16 CWG and 20 CWM patients who completed the protocol. Core temperature increased in both groups during the initial hours of surgery. We had sufficient evidence (P=0.001), to conclude that the combination of a CWM and forced-air warming was non-inferior to a CWG in preventing temperature reduction, with mean (95% CI) difference in the temperature change between the CWM and the CWG groups (CWM-CWG) of 0.46°C (-0.09°C, 1.00°C). CONCLUSIONS The combination of a CWM and forced-air warming is significantly non-inferior in maintaining intraoperative core temperature than a CWG. TRIAL REGISTRY This trial has been registered at clinical trials.gov, identifier: NCT 00651898.

Predicting Immunosuppressant Dosing in the Early Postoperative Period with Noninvasive Indocyanine Green Elimination Following Orthotopic Liver Transplantation

Investigations have demonstrated conflicting results regarding the influence of the red blood cell (RBC) storage duration on outcomes. We evaluated whether graft failure or mortality after orthotopic liver transplantation (OLT) increased when recipients were transfused with older RBCs. This study included 637 patients who underwent OLT between January 2001 and June 2011. Baseline and perioperative data were obtained from our blood bank, the Unified Transplant Center database, and the United Network for Organ Sharing database. Recipients whose transfused RBCs were all stored for ≤15 days were grouped in a younger group, and recipients who were transfused with RBCs stored for >15 days were placed in an older group. The relationship between graft survival/mortality and the age of intraoperatively transfused RBCs was studied by Kaplan‐Meier estimation with a log‐rank test and multivariate Cox proportional hazards regression. Three hundred thirty‐four patients and 303 patients were grouped in the younger and the older RBC groups, respectively, on the basis of the ages of intraoperatively transfused RBCs. Kaplan‐Meier estimates of graft survival/mortality as a function of the posttransplant time were significantly different: the older group experienced the outcome sooner than the younger group [P = 0.02 (log‐rank test)]. After covariate adjustments, the risk of graft failure/mortality was significantly different at any given time after transplantation between patients receiving intraoperative transfusions of older RBC units and patients receiving intraoperative transfusions of younger RBC units (hazard ratio = 1.65, 95% confidence interval = 1.18‐2.31). In conclusion, patients who received intraoperative transfusions of RBCs with longer storage times had an increased risk of adverse outcomes. Liver Transpl 19:1181–1188, 2013.

Sharps disposal in the operating room: Current clinical practices and costs

Twenty adult patients undergoing orthotopic liver transplantation (OLT) were enrolled in this study, with the noninvasive indocyanine green plasma disappearance rate (ICG‐PDR) measured both during and after OLT to assess the relationship between ICG‐PDR and the ability of patients to achieve therapeutic postoperative tacrolimus immunosuppressant blood levels. Liver function was determined at both 2 and 18 hours post reperfusion with the ICG‐PDR k value (1/min). Postoperative standard serum measures of liver function as well as liver biopsies were also collected and analyzed. The median ICG‐PDR k value for the study group at 2 hours post reperfusion was 0.20 (0.16, 0.27), whereas at 18 hours post reperfusion, it was 0.22 (0.18, 0.35). The median change in the k value between the two ICG‐PDR measurements was 0.05 (−0.02, 0.07) with P = 0.02. There was an interaction between the postoperative day 1 (18 hours post reperfusion) ICG‐PDR k value and the linear increase in the tacrolimus blood level, such that the greater the k value was, the more gradual the observed rise was in tacrolimus over time [that is, the longer it took to achieve a therapeutic blood level (>12 ng/mL), P = 0.003]. Of the 16 patients that received tacrolimus, comparable dosing on a per kilogram body weight basis was observed. Also, no significant association between ICG‐PDR k values and postoperative liver biopsy results was seen. This study demonstrates that the ICG‐PDR measurement is a modality with the potential to assist in achieving adequate blood levels of tacrolimus following OLT. Liver Transpl 14:46–52, 2008.