Anesthesiology 2019 Projects

Optimizing the allocation of blood products used by the UFCHC

Faculty Mentor’s Name: Dr. Kevin Sullivan
Phone: 904-654-4427
Email: ksullivan@anest.ufl.edu

Student: Samuel Armington
Email: samarmington@ufl.edu

Research Project Description:

Blood transfusion involves the administration of packed red cells, fresh frozen plasma, cryoprecipitate, and platelets which collectively are referred to as blood products. Transfusion of blood products is essential for many surgeries, particularly pediatric cardiac surgery. Unfortunately, blood products are frequently wasted despite their importance. One study found that 25% of the blood products were wasted in a single hospital (Kurup et al.). Due to the hospital wide demand, and the relatively significant waste, it is imperative that ordering physicians and blood banking service work together to more efficiently allocate this precious resource. To do this, various strategies are being developed and employed (Eeles and Baikady; Singh). We believe that a comprehensive strategy that measures blood utilization and stratifies it by patient age, size, re-operation status, and complexity of surgical lesion will allow us to both estimate and aliquot blood products so that blood banked units can be partitioned for use both in the operating room and for the perioperative period in the intensive care unit. Under the current paradigm, incomplete aliquots of blood units are utilized with the remainder being wasted. We seek to define practices and promote protocols that allow for the complete utilization of this precious and expensive resource.

The following data points will be collected:

  1. The procedure conducted
  2. The estimated blood loss
  3. The amount of packed RBCs, fresh frozen plasma, cryoprecipitate, and platelets ordered
  4. The amount of each product transfused
  5. The amount of each product wasted
  6. The amounts of each product returned unused
  7. The fate of the unused and returned units (had to be wasted by blood bank statutes vs. found a new recipient)
  8. The amount of time taken to fulfill an order

Blood Cardiac Surgery Utilization Study

Faculty Mentor’s Name: Dr. Kevin Sullivan
Phone: 904-654-4427
Email: ksullivan@anest.ufl.edu

Student: Christian Eskander
Email: c.eskander@ufl.edu

Research Project Description:

The project consists of both a prospective cohort from April to July 2019, and a retrospective cohort for the past 2 years starting April 2017. In the prospective cohort, we are having the perfusionists, and anesthesiologists in each surgery enter all blood units used and unused, opened and unopened, including not only the blood administered by anesthesia, but also in the cardiopulmonary bypass machine. The retrospective cohort will be looking at similar information, but only for blood administer by anesthesia. We will use Epic to view the data entered by the medical team prospectively and retrospectively and collect it with the REDcap tool. We will be looking at multiple parameters and evaluate based not only on the amount of blood used and unused, but also based on what kind of surgery was preformed, as different types of surgeries may have different blood usage efficiency rates.

Micro SpO2 Changes and Respiration Rate

Faculty Mentor’s Name: Dr. Nikolaus Gravenstein
Phone:
Email: ngravenstein@anest.ufl.edu

Student: Leila Shafiq
Email: lshafiq@ufl.edu

Research Project Description:

The central hypothesis is that respiration rate is detectable via micro (fractional) SpO2 changes using finger or nasal alar SpO2 sensors. The rationale underlying this proposal is that having a new method to continuously obtain respiration rate is clinically useful for the diagnosis of respiratory pathology. Additionally, early detection of changes in respiration rate can assist in prompt identification of deterioration of a patient’s condition.

The objective of this project will be accomplished by the following specific aims:

(1) Identify a method to signal process micro SpO2 changes in order to record an output of respiration rate.

(2) Measure the metronome-guided respiration rates of volunteers using a finger and a nasal alar SpO2 sensor as compared to the gold standard of End-Tidal CO2 (EtCO2).

(3) Analyze data obtained to determine if either a finger or a nasal alar SpO2 sensor offers a reliable method of obtaining respiration rate.

Safety of Pediatric Scheduling Assignments

Faculty Mentor’s Name: Dr. Kevin Sullivan
Phone: 904-654-4427
Email: kevinsullivan@ufl.edu

Student: Evan Johns
Email: ejohns@ufl.edu

Research Project Description:

Modern anesthesia services in academic medical centers are often provided in a model of concurrent care wherein an anesthesia faculty member supervises residents, nurse anesthetists, or anesthesia assistants. The methods employed for assigning multiple operating rooms of pediatric and or adult patients may directly impact the safety of the care provided and is a concern for practicing anesthesiologists.
In this hypothesis generating quality assurance program the medical student will work with the pediatric anesthesia faculty to determine risk factors and interventions that minimize risk and maximize safety for pediatric anesthesia services.

A Retrospective Chart Review: Post-Operative Effects of Cuffed vs Un-cuffed ETTs in Infants Undergoing Cardiac Surgery

Faculty Mentor’s Name: Dr. Kevin Sullivan
Phone: 904-654-4427
Email: kevinsullivan@ufl.edu

Student: Allyson Tragesser
Email: atragesser@ufl.edu

Research Project Description:

This project is a quality assurance, retrospective chart review. We will be using REDcaps to capture the data involved.

There is a lack of literature on the type of endotracheal tubes that should be used in an infant undergoing intubation for surgery. This calls for investigation in order to reduce the possibility of airway damage. The presence or absence of the newer cuff mechanism (high volume, low pressure cuffed endotracheal tube) may lead to different post-operative outcomes. There are numerous consequences1 that can arise from improper use of endotracheal tubes, posing a need for a protocol when intubating infants.

Airway damage is mostly due to too large of a tube(1), but there is unclear evidence if the cuffed tubes in infants play a role in minimizing this risk. The cuffed tube seals in the muscular walls of the trachea preventing air leak and aspiration in the sub-glottis region, while the un-cuffed tubes seal against the cricoid cartilage. This suggests that a larger tube may be more harmful because it has the potential to damage the trachea with direct and forceful contact with the cricoid(1). However, radius is sacrificed in using a cuffed ETT, so the resistance is much greater, making air flow reduced and ventilation more difficult.

Previous literature suggested that cuffed tubes in children under 8 years old were unnecessary because the cricoid is the narrowest portion and will prevent aspiration(2). This was before our knowledge of the trachea anatomy of infants changed. Previously, the trachea was thought to be funnel-shaped, however, more recent MRI studies have shown that it is more cylindrical like an adult’s trachea and the sub-glottis region is the narrowest part of the trachea (2,3). This makes UETT (un-cuffed endotracheal tubes) more harmful since the cricoid is not entirely circular and more prone to ischemia and compression(3). A study conducted last year(4) showed that CETT yield similar results in patients <3 kg, and were safe to use, however this retrospective review showed an extremely small sample size and was not investigating high-risk surgeries in specific. The current guidelines allow us to determine what size endotracheal tube we should use(5) depending on age of the child and whether it will be cuffed or un-cuffed, but there is not yet a protocol advising for which one to use in infants

Early Extubation in Liver Transplant Patients

Faculty Mentor’s Name: Dr. Rensheng Zhang
Phone:
Email: rzhang@anest.ufl.edu

Student: Erich Zellmer
Email: ezellmer@ufl.edu

Research Project Description:

Early extubation has been shown to be beneficial in a selected group of liver transplant recipients and demonstrates benefits such as improved regional blood flow to liver graft from increased venous return, reduced ICU stay (Zeyneloglu et al), and possibly reduced postoperative pulmonary complications. Several studies demonstrated the safety and feasibility of early or immediate extubation in liver transplant patients with good pretransplant conditions and uncomplicated intraoperative course. Despite the data, some anesthesiologists may still be reluctant to extubate any liver transplant patients in the OR due to concerns for encephalopathy, large blood loss, fluid shifts, hemodynamic instability and metabolic derangements. Others who aim to extubate in the OR may base their judgments on experience and clinical gestalts.

Careful patient selection is key to avoiding compromising patient safety from premature extubation. Successful early extubation depends on multiple patient and physiologic factors. In the literature, there have been attempts to identify these preoperative and intraoperative factors that predicts successful early extubation. For example, Skurzak et al (2010) develop the SORELT (Safe Operating Room Extubation after Liver Transplantation) score consisting of 2 major and 3 minor criteria derived from retrospective data from 597 OLT who either were or were not immediately extubated. Major criteria found included 1) <7 units of packed RBCs transfused intraoperatively; 2) end of surgery lactate <3.4 mmol/L. Minor criteria included 1) patient at home pretransplant; 2) duration of surgery <5 hours; 3) vasoactive infusions at end surgery (dopamine <5 μg/kg/min or norepinephrine <0.05 μg/kg/min). Due to heterogeneity of patient population and surgical and anesthetic practice at each institution, these objective scoring systems still require further external validation. Many features from the SORELT score were subsequently reproduced in the study by Lee et al in 2014 in living donor liver transplant recipients who reported major predictors for extubation within 1 hour of surgery end included pRBC transfused <7 units and final intraoperative lactate<=8.2 mmol/L, which is a much higher threshold partly due to graft related factors of living donor LT compared with OLT. The amount of pRBC transfusion also appears to be a consistent major predictor of successful early extubation across many other studies, each study found different cutoff values (12 units in Biancofiore et al; 10 units in Cammu et al; 6 units in Glanemann et al). Perhaps measuring the ml/kg instead of units transfused will help normalize the values across different patient sizes and be more indicative of amount transfused in proportion to individual’s estimated blood volume.

At our institution from 2000 to 2008, a consistent group of anesthesiologists routinely aimed to extubate in the operating room. Due to the absence of specific guidelines for immediate extubation after liver transplant other than general extubation criteria, most providers presumably made their judgement based on clinical gestalts and experience.

Disclaimer: The images on this page were taken prior to the national guidelines of face coverings and social distancing.