William T. Merritt

Optimizing preoperative blood ordering with data acquired from an anesthesia information management system

Background:The maximum surgical blood order schedule (MSBOS) is used to determine preoperative blood orders for specific surgical procedures. Because the list was developed in the late 1970s, many new surgical procedures have been introduced and others improved upon, making the original MSBOS obsolete. The authors describe methods to create an updated, institution-specific MSBOS to guide preoperative blood ordering. Methods:Blood utilization data for 53,526 patients undergoing 1,632 different surgical procedures were gathered from an anesthesia information management system. A novel algorithm based on previously defined criteria was used to create an MSBOS for each surgical specialty. The economic implications were calculated based on the number of blood orders placed, but not indicated, according to the MSBOS. Results:Among 27,825 surgical cases that did not require preoperative blood orders as determined by the MSBOS, 9,099 (32.7%) had a type and screen, and 2,643 (9.5%) had a crossmatch ordered. Of 4,644 cases determined to require only a type and screen, 1,509 (32.5%) had a type and crossmatch ordered. By using the MSBOS to eliminate unnecessary blood orders, the authors calculated a potential reduction in hospital charges and actual costs of

Preoperative lumbar epidural morphine improves postoperative analgesia and ventilatory function after transsternal thymectomy in patients with myasthenia gravis

211,448 and

A new percutaneous technique for establishing venous bypass access in orthotopic liver transplantation

43,135 per year, respectively, or

Predictive Modeling of Massive Transfusion Requirements During Liver Transplantation and Its Potential to Reduce Utilization of Blood Bank Resources

8.89 and

The prognostic value of the furosemide stress test in predicting delayed graft function following deceased donor kidney transplantation

1.81 per surgical patient, respectively. Conclusions:An institution-specific MSBOS can be created, using blood utilization data extracted from an anesthesia information management system along with our proposed algorithm. Using these methods to optimize the process of preoperative blood ordering can potentially improve operating room efficiency, increase patient safety, and decrease costs.

Needles, Needles, Everywhere!

ObjectiveTo test the hypothesis that preoperative lumbar epidural morphine improves postoperative pain control and ventilatory function after transsternal thymectomy in patients with myasthenia gravis. DesignThe study design was randomized, placebo-controlled, and double-blind. SettingAfter surgery, all patients were admitted to the Neuroscience Critical Care Unit for evaluation and treatment. PatientsAll patients with myasthenia gravis who presented to the hospital for thymectomy were asked to participate in the study. Twenty patients were randomized to either the placebo or epidural morphine groups. InterventionsPatients received either epidural morphine (7 mg in 14 mL of sterile saline) or saline (14 mL) before induction of anesthesia. Supplemental iv opioids were administered intraoperatively, with need determined by the anesthesiologist. Main Outcome MeasuresThe main outcome measures were indicators of postoperative pain (e.g., Visual Analog Pain Score, requirement for supplemental opioid administration, respiratory rate) and ventilatory function (e.g., forced vital capacity, negative inspiratory pressure). ResultsImmediately after surgery, the Visual Analog Pain Score in the placebo group was twice as high as the score in the epidural morphine group (placebo 7.0 ±PT 1.3; epidural morphine 3.5 ±PT 1.2, p < .05). During the first eight postoperative hours, the placebo group required more opioids (0.22 ±PT 0.03 vs. 0.12 ±PT 0.04 mg/kg morphine equivalents, p < .06) than the epidural morphine group. Later, both groups received similar amounts of opioids. Patients receiving epidural morphine had better initial recovery of forced vital capacity (at 8 hrs: 55 ±PT 6% [epidural morphinel vs. 34 ±PT 5% [placebo] of preoperative value, p < .05). Respiratory rate was lower for the first 12 postoperative hours in the epidural morphine group, without a difference in Paco2. There was no difference between groups for the duration of postoperative intubation or ventilation. ConclusionsPreoperative lumbar epidural morphine facilitates postoperative analgesia and improves initial postoperative ventilatory performance.

Metabolism and liver transplantation: Review of perioperative issues

Partial veno-venous bypass (VVB) is commonly used in orthotopic liver transplantation (OLT). Venous access for blood return during VVB classically uses a surgical cutdown on the left axillary vein (LAV), which may prolong operating time and can be associated with significant complications. The authors have developed an alternative means of establishing venous access whereby the anesthesia team places 8.5F venous cannulae preoperatively in one or two vessels (internal jugular, antecubital, or subclavian) percutaneously using the Seldinger technique. These cannulae then serve to accept venous return from below the diaphragm via a centrifugal pump. The aim fo the present study was to compare the hemodynamic profiles obtained during the anhepatic phase of OLT in patients in whom either a conventional LAV catheter (group 1) or percutaneous catheters (group 2) were used for return flow from a centrifugal pump. There were no identifiable complications related to venous access in either group of patients. Total operating room time was 800 +/- 30 minutes in group 1 and 720 +/- 40 minutes in group 2 (P = 0.17). Hemodynamic parameters were determined from continuous strip chart recordings of arterial, right atrial, and inferior vena caval (IVCP) pressures. Cardiac output (CO) was measured by thermodilution whereas pump flow was determined by an electromagnetic probe. Renal perfusion pressure (RPP) was calculated as the difference between mean arterial pressure (MAP) and IVCP. Bypass pump flow was greater, but not significantly different between group 1 (3.0 +/- 0.2 L/min) and group 2 (2.4 +/- 0.2 L/min) (P = 0.09).(ABSTRACT TRUNCATED AT 250 WORDS)

Intrapartum Orthotopic Liver Transplantation With Successful Outcome Of Pregnancy

BACKGROUND: Patients undergoing liver transplantation frequently but inconsistently require massive blood transfusion. The ability to predict massive transfusion (MT) could reduce the impact on blood bank resources through customization of the blood order schedule. Current predictive models of MT for blood product utilization during liver transplantation are not generally applicable to individual institutions owing to variability in patient population, intraoperative management, and definitions of MT. Moreover, existing models may be limited by not incorporating cirrhosis stage or thromboelastography (TEG) parameters. METHODS: This retrospective cohort study included all patients who underwent deceased-donor liver transplantation at the Johns Hopkins Hospital between 2010 and 2014. We defined MT as intraoperative transfusion of > 10 units of packed red blood cells (pRBCs) and developed a multivariable predictive model of MT that incorporated cirrhosis stage and TEG parameters. The accuracy of the model was assessed with the goodness-of-fit test, receiver operating characteristic analysis, and bootstrap resampling. The distribution of correct patient classification was then determined as we varied the model threshold for classifying MT. Finally, the potential impact of these predictions on blood bank resources was examined. RESULTS: Two hundred three patients were included in the study. Sixty (29.6%) patients met the definition for MT and received a median (interquartile range) of 19.0 (14.0–27.0) pRBC units intraoperatively compared with 4.0 units (1.0–6.0) for those who did not satisfy the criterion for MT. The multivariable model for predicting MT included Model for End-stage Liver Disease score, whether simultaneous liver and kidney transplant was performed, cirrhosis stage, hemoglobin concentration, platelet concentration, and TEG R interval and angle. This model demonstrated good calibration (Hosmer-Lemeshow goodness-of-fit test P = .45) and good discrimination (c statistic: 0.835; 95% confidence interval, 0.781–0.888). A probability cutoff threshold of 0.25 was found to misclassify only 4 of 100 patients as unlikely to experience MT, with the majority such misclassifications within 4 units of the working definition for MT. For this threshold, a preoperative blood ordering schedule that allocated 6 units of pRBCs for those unlikely to experience MT and 15 for those who were likely to experience MT would prevent unnecessary crossmatching of 338 units/100 transplants. CONCLUSIONS: When clinical and laboratory parameters are included, a model predicting intraoperative MT in patients undergoing liver transplantation is sufficiently accurate that its predictions could guide the blood order schedule for individual patients based on institutional data, thereby reducing the impact on blood bank resources. Ongoing evaluation of model accuracy and transfusion practices is required to ensure continuing performance of the predictive model.

Evidence-based medicine in anesthesiology

Abstract Objectives and methods: The Furosemide Stress Test (FST) is a novel dynamic assessment of tubular function that has been shown in preliminary studies to predict patients who will progress to advanced stage acute kidney injury, including those who receive renal replacement therapy (RRT). The aim of this study is to investigate if the urinary response to a single intraoperative dose of intravenous furosemide predicts delayed graft function (DGF) in patients undergoing deceased donor kidney transplant. Results: On an adjusted multiple logistic regression, a single 100 mg dose of intraoperative furosemide after the anastomosis of the renal vessels (FST) predicted the need for RRT at 2 and 6 h post kidney transplantation (KT). Recipient urinary output was measured at 2 and 6 h post furosemide administration. In receiver-operating characteristic (ROC) analysis, the FST predicted DGF with an area-under-the curve of 0.85 at an optimal urinary output cut-off of <600 mls at 6 h with a sensitivity of and a specificity of 83% and 74%, respectively. Conclusions: The FST is a predictor of DGF post kidney transplant and has the potential to identify patients requiring RRT early after KT.

Successful liver transplantation in a patient with budd‐chiari syndrome caused by homozygous factor V leiden

A 55-YR-OLD man with endstage renal disease presented for emergent removal of an infected arteriovenous dialysis graft. This patient had multisystemic disease, including hepatitis C, human immunodeficiency virus, cardiomyopathy, and atrial fibrillation. He also had a history of left internal jugular thrombosis and right common carotid septic pseudoaneurysm, corrected via partial sternotomy. A chest x-ray film taken in the emergency department revealed partial sternotomy wires, but also showed countless metallic fragments distributed throughout the neck (see magnified view in center of x-ray film), chest, and upper arms. These were consistent with broken needle fragments and longstanding intravenous drug abuse. Visual examination of the neck revealed some mild scarring; gentle palpation did not suggest embedded needles. We avoided upper trunk/neck central intravenous access because of two concerns: the risk to the healthcare provider from the sharp needles, and the possibility for dislodgement/embolization of an intravascular needle. Findings of retained needles in patients with a history of intravenous drug abuse have been reported previously, and patients are often asymptomatic. Retained needles due to acupuncture as well as the use of charm needles has also been described. Healthcare providers should be aware of this association with intravenous drug abuse. This is an additional reason to consider the use of ultrasound guidance for central and deep venous access line placement, and suggests the use of extreme care when examining patients, especially those with a known history of drug abuse. A careful history and examination of x-ray films before central line placement is suggested to identify retained needle fragments.