Stats Proposal/Nursing

TABLE OF CONTENTS

CHAPTER 1:

1.1 Introduction 4

1.2 Statement of the problem 4

1.3 Purpose of the study 5

1.4 Need for the study 5

1.5 Delimitations 7

1.6 Limitations 7

1.7 Assumptions 8

1.8 Hypothesis 8

CHAPTER 2:

2.1: Review of Literature 9

2.2: Relation to Literature 14

2.3: Conclusion and Summary 15

CHAPTER 3:

3.1: Research Design 16

3.2: Subjects 16

3.3: Intervention 16

3.4: Variables 17

3.5: Sources of Information 17

3.6: Instrumentation

3.7: Procedures 18

3.8: Ethical Considerations 18

3.9: Data Analysis 18

CHAPTER 4:

Conclusion 19

References 20

Chapter 1

Introduction

Implementing a more accurate method for measuring the levels of oxygenation in the pediatric population during cardiac surgery may help in deterring the neurological sequelae that can occur when oxygen supply does not meet oxygen demand in the brain (Austin, Edmonds, Auden, Seremet, Niznik, Sehic, Sowell, Cheppo, and Corlett, 1997).

Hypoxic-ischemic mechanisms are the major cause of neurological injury in pediatric cardiac surgery. This type of injury can be prevented if monitoring detects potentially harmful conditions early enough to allow initiation of effective interventions before irreversible injury can occur. Because the neurodevelopmental effects of central nervous system injury in a pediatric patient may not manifest until a number of years later, rational approaches to injury prevention based largely on strategies to avoid known pathophysiologic risk factors, particularly hypoxia. Although vital organs are routinely monitored during congenital heart surgery with cardiopulmonary bypass (CPB), the brain is not typically monitored. Any strategy for prevention of neurological events in children must begin with the routine use of neurological monitoring systems that allow easy, reliable, and reproducible detection of events.

Problem Statement

1. Will initiation of continued cerebral monitoring during pediatric cardiac surgery reduce negative neurological outcomes for the pediatric population in the immediate post-operative period?

2. Will use of cerebral monitoring improve neurological outcomes for the population at five years post-operatively?

Purpose

Given the multiple linkages between hypoxic-ischemic risk and reduced neurodevelopmental outcome, a straightforward perioperative strategy is introduced: increase the detection, treatment, and prevention of brain hypoxia throughout the period of physiological risk. This will be done with initiation of a near infrared spectrometry (NIRS) device that will directly monitor blood flow of the cerebral vasculature (Hoffman, 2006). Vast quantities of evidence exist in the area of NIRS usage and its immediate positive outcomes. However, little is known of the long-term effects of this type of patient monitoring. This study will determine if the use of the NIRS system of monitoring pediatric oxygenation is superior to conventional pulse oximetry method and if it influences the population neurodevelopmentally five years post-operatively.

Need for the study

The reported incidence of neurological complications after heart surgery in children ranges from 2% to 25% (Andropoulos, Stayer, Diaz, and Ramamoorthy, 2004). Postoperative neurologic problems have traditionally been thought to result largely from the operation: from periods of hypothermic circulatory arrest, from cardiopulmonary bypass (CPB) itself, as well as from complications of bypass (hypotension, embolic phenomena, anticoagulation), and from edema associated with the systemic inflammatory response. Efforts to avoid circulatory arrest when possible may improve neurological outcome. However, the use of CPB and occasional circulatory arrest are required for the repair of some cardiac defects (Fenton, Freeman, Glogowski, Fogg, and Duncan, 2005). Intervention based on neurologic monitoring appears to decrease the incidence of postoperative neurologic impairment and reduce the length of stay for the patient (Austin, Edmonds, Auden, Seremet, Niznik, Sehic, Sowell, Cheppo, and Corlett, 1997).

Currently the standard of monitoring does not include the brain specifically in regards to perfusion and oxygenation trends. The use of the standard pulse oximetry is a device placed on the foot, toe, or finger of the pediatric patient. An infrared light passes through the tissue of location and a reading of oxygenation is created, known as SaO2 or saturated hemoglobin (oxygen carrying component of the blood). The technique has limitations such as cardiac output fluctuations, temperature changes, and does not take into account patient size or disease processes such as anemia or polycythemia. The current technique can be affected by light and injection of various medications such as methylene blue or indigo carmin, which is occasionally administered in the operating room. The inaccuracy of the device is well known. However, due to familiarity with the device, it has become a standard in today's hospital setting. Research conducted by the Neonatal Neurology department at Miami Children's Hospital in 2006, performed a study using NIRS monitoring as well as SaO2 monitoring on a child with status epilepticus (persistent seizures lasting longer than average) to see the variance in cerebral perfusion in regards to changes in contemporary monitoring systems. It found that the NIRS system closely correlates with the electroencephalogram during seizure activity, but there was no significant blood pressure and systemic oxygen saturation (SaO2) changes