Free Virtual Mechanical Ventilator

OPENPediatrics website provides a free virtual mechanical ventilator that allows users to review mechanical ventilator knowledge, play scenarios, and test their skills with case simulations.

One just needs to register for free on their "Clinician Community Site" to utilize the simulator. 

LINKS

OPENPediatrics

OPENPediatrics simulator

OPENPediatrics Clinician Community  Site

RELATED POST

Creating Flow Mismatch with a Simulator

Arterial Waveform Analysis Devices

Image 1: From PiCCO @ Bedside, iOS Mobile app [1]. 

Due to the results of the March 2014 "ProCess Trial" indicating that early goal directed therapy in septic shock did not improve outcomes [2] , there has been less interest in using pulse contour analysis devices to optimize fluid management in the critically ill patient. 

The main reason for this is that these devices, even though less invasive then the pulmonary artery catheter still require at the minimum an arterial line and in addition (depending on device) a central venous catheter. 

However, before letting these devices collect dust on a shelf, I believe this tool can be still be very beneficial in two patient populations.

One, is the high risk surgical patient to optimize fluid management.

This strategy is currently termed "Goal directed Intra-operative fluid administration".

Fluid overload during surgery has been associated with [3]:

-Increased length of stay

-Bowel wall edema

-Edema organ dysfunction

-Adverse outcomes

Additionally, patients receiving fluid and hemodynamic optimization during surgery are at an decreased risk of renal impairment. 

The second type of patient that may benefit from minimally invasive cardiac output monitoring is the critically ill cardiovascular patient.

 With these patients the ICU physician is always questioning [4]:

-"Is the patient's pre-load sufficient to obtain adequate Cardiac output"?

-"Does the patient need volume (fluids) or forced diuresis"?

-"What is the patient's cardiac function"?

-"Does the patient need inotropes or pressors"?

In these patients'  not optimizing fluid management can be detrimental. 

TECHNOLOGY

All devices calculate cardiac output based on the traditional equation:

CO = SV X HR

CO = Cardiac Output

SV= Stroke volume

HR= Heart rate 

However, each device uses a proprietary method to calculate stroke volume or a modification of the Fick principle. Below is a table I created that compares and contrast three different pulse contour analysis devices.  

Image 2: Table comparing Pulse Contour Analysis Devices.

For more information on Arterial Waveform Analysis Devices one can visit the Society of Critical Care Medicine and take the online course "Less-Invasive Hemodynamic Monitoring" [5]. 

REFERENCE

1. PiCCO @ Beside, GE HealthCare iOS mobile app

2. Early Goal Directed Therapy Does Not Improve Outcomes in Septic Shock (ProCESS)

3. Optimization of the High Risk Surgical Patient. SCCM, lecture 2014

4. Transpulmonary Thermodilution. SCCM, lecture 2014. 

5. Less-Invasive Hemodynamic Monitoring. 

FREE Mechanical Ventilation Handouts

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ROBERT CHATBURN: Author Page

Whats in your pockets? Are you a Prepper or Macgyver?

In a previous post (The RT Hoarder) I mention that I carry very little on me when I'm at work. 

Yes, I believe in being prepared, however I try to practice the "Macgyver" philosophy [1], versus the "Dooms Day Prepper" mentality [2].

This post presents my Everyday Carry (EDC) [3] from when I first started in the field of respiratory therapy to what I carry now. I will describe "what is in my pockets" and why, also notice the progression throughout the years.

What items do I get rid of & what do I always need to practice the profession?

EDC as a RT student & new graduate.

CPAP as a LOW TIDAL VOLUME VENTILATION STRATEGY

Image 1: Ventilator Screen Shot of Continuous Positive Airway Pressure. 

In October’s issue of the Chest Journal, a few colleagues of mine authored the abstract “The Use of Invasive Continuous Airway Pressure for Low Tidal Volume Ventilation”.

 This abstract was very intriguing to me for various reasons, one this goes against many traditional methods of providing ventilatory support for the patient with Acute Lung Injury and/ or ARDS.

Zealots of Airway Pressure Release Ventilation would argue that using pure CPAP would lead to extreme work of breathing and not off load the respiratory muscles sufficiently.

I myself would be concerned about using CPAP only, especially in extra-pulmonary ARDS primarily sepsis and septic shock where patients metabolic demand is high, which leads to a vigorous inspiratory demand. Off-loading these patients is very difficult and even using APRV or traditional methods leads to severe hypercapnea.  

However, I was baffled so I questioned my friend Troy Whitacre, a coauthor of the abstract to find more details and to share his experience.

Free Bronchoscopy Simulator

Free Bronchoscopy Simulator

http://www.thoracic-anesthesia.com/

Setting Ventilator Alarms Diagnostically

Many practitioners set alarm thresholds thoughtlessly due to the fact that many ventilators do a poor job of filtering alarm nuisances versus 'high-risk' alarms. Many times I see the high respiratory rate alarm set at threshold in which the patient would have severe air trapping and dynamic hyperinflation before the alarm threshold is met.

When using controlled modes of ventilation (VC-CMV & PC-CMV) it is extremely important to set the high respiratory rate alarm threshold appropriately.

During both machine and patient initiated breaths the inspiratory time is fixed, so any additional breaths takes away from the expiratory time which can quickly lead to a inverse inspiratory-to-expiratory (I: E) ratios.

How to set the High Respiratory Rate Alarm Diagnostically

In patients with obstructive airway disease I prefer to set my high
respiratory rate based on a 1:1, I: E ratio. 
That is when the patient sets off the high respiratory rate alarm I know that they are breathing at a 1:1 ratio and that any additional breaths will be an inverse I: E ratio, putting the patient at a increased risk for dynamic hyperinflation.

This is easy to calculate based on the patient's set inspiratory time.

Formula: x = 60/(I-time * 2)
X (high respiratory rate alarm)
60 (total cycle time)
I-time (machine set I-time)

A common I-time is 1.0 second this would equal a high respiratory rate alarm of 30 breaths/minute. This stays the same if the set rate is 8 or 25; the 1:1 threshold is at 30 breaths/min.

The 0.25 Second difference

If air trapping is a concern just decrease the I-time.
A 0.25 second change is significant. 


Decreasing the I-time from 1.0 second to 0.75 second increases the
alarm threshold to 40 bpm.

EFFECT OF THE RAPID RESPONSE TEAM ON RESPIRATORY AND CARDIOPULMONARY ARRESTS WITHIN NON-CRITICAL CARE UNITS

Background: Rapid Response Teams (RRT) are groups of healthcare practitioners who respond to acutely-deteriorated hospitalized patients. Various studies have shown that RRT’s may improve patient outcomes. Additionally, the Institute for Healthcare Improvement recommends the implementation of RRT’s as one of their initiatives to improve patient safety outcomes. 

Objective: We implemented an RRT (An Internal Medicine Physician, Registered Respiratory Therapist, Critical Care Registered Nurse and Nursing Supervisor) at Sentara Careplex Hospital in 2005 specifically to reduce the monthly rate of respiratory and cardiopulmonary arrests (codes) external to the intensive care units.

Design: Single center, non-randomized, prospective chart review.

Setting: 199 bed community hospital.

Interventions - The records of patients who required cardiopulmonary resuscitation external to the intensive care areas were reviewed before RRT implementation to determine activation criteria for the RRT. Codes were defined as respiratory or cardiopulmonary arrest. The incidence of these non-ICU codes before and after RRT implementation was recorded. The one-way analysis of variance (ANOVA) was used for statistical testing of differences between years 2004 (pre RRT implementation), 2005, 2006, and 2007. A p value < 0.05 was considered statistically significant.

Results: Previous to RRT implementation, the non-ICU code rate averaged 5.33 events per month. After implementation, the mean non-ICU code rate decreased by an average of 21%. Conversely, when testing for significant differences between pre & post RRT implementation, there were no statistical differences among the four years (p-value 0.15).

Conclusion: Although our facility met its goal by decreasing the non-ICU code rate by 10%, there was no significant statistical difference pre & post RRT implementation. The cost of intensive care unit length of stay and unplanned ICU admissions is of great relevance. Additionally, patient-centered outcomes such as health-related quality of life and hospital mortality rates must be addressed. 

Apneic Oxygenation Diffusion to Determine Apnea: Is it Safe?

The apnea test is a component in the determination of brain death. One technique used to evaluate the absence of breathing drive is to perform the "Apneic Oxygenation Diffusion Technique" also know as a "CO2 Challenge". In 1995 the American Academy of Neurology published prerequisites and parameters to perform this clinical assessment[1].

In his recent journal article "A Critique of the Apneic Oxygenation Test for the Diagnosis of Brain Death"[2], Dr. James Tibballs provides a strong argument against the utility and questions the safety of the apnea test.

The author proposes four areas of concern to fortify his disagreement:

1. The reliability of apnea with a rise in PaCO2 as a neurological diagnostic of brain death.
2. The potential for injury due to the unpredictable rise in PaCO2.
3. The large amount of variability, in regards to performance of the technique.
4. There are other tests which can be performed, which are superior. 

In the News -CMS Finalizes Inpatient Hospital Rules

The Centers for Medicare & Medicaid are proposing to change regulations which would allow Physician Assistants and Nurse Practitioners’ to write orders for Respiratory Care Services without a co-signature from a physician.

I believe this is an area of concern since respiratory care services specifically ventilator management is highly specialized. Additionally, there is no formal training regarding ventilator management in PA or NP programs, as a minimum pulmonary physicians have to train as fellow.
The below case study submitted from a colleague will articulate my point of view.