How Much Of A Safety Margin For Transcutaneous Pacemaker?

Answer The Question

How much of a safety margin should you allow when using the transcript Aeneas pacemaker

Usual practice is to have a pacing safety margin of at least 2 times (or 3 times if the patient has an unstable escape rhythm) – if the pacing threshold is 3, set at 7 (or 10).

What is the initial impulse setting for a transcutaneous pacemaker

Set initial pacing rate at 80 bpm.7. Select output level: begin at 10 mA and increase by 10 mA until capture/pulses are noted, then increase output by an additional 10 mA.

What is the initial impulse setting for a transcutaneous pacemaker bradycardia?

Transcutaneous pacing (TCP) – Preparation for TCP takes place as atropine is being given. If atropine fails to alleviate symptomatic bradycardia, TCP is initiated, Ideally, the patient receives sedation prior to pacing, but if the patient is deteriorating rapidly, it may be necessary to start TCP prior to sedation.

1. For the patient with symptomatic bradycardia with signs of poor perfusion, transcutaneous pacing is the treatment of choice.
2. Do not delay TCP for the patient with symptomatic bradycardia with signs of poor perfusion.
3. The starting rate for TCP is 60-80/min and adjust up or down based on the patient’s clinical response.

The dose for pacing is set at 2mA (milliamperes) above the dose that produces observed capture. TCP is contraindicated in the patient with hypothermia and is not a recommended treatment for asystole, Do not use a carotid pulse check for the assessment of circulation as TCP can create muscular movements that may feel like a carotid pulse.

What is pacemaker threshold value?

Pacing threshold was defined as the minimum voltage that could produce five consecutive stimuli and was measured at a pulse duration of 0.5ms. The pacing threshold of all implanted ventricular leads was under 1.0V.

What is pacing threshold value?

Pacing threshold and pulse width is defined as the minimum amount of energy needed to capture the myocardial tissue electrically.

What is the good level of margin of safety?

What is a good margin of safety percentage? – Generally speaking, the higher your margin of safety, the safer your company. The value represented by your margin of safety is your buffer against becoming unprofitable. In the real world, the minimum margin of safety percentage to aim for generally depends on your cost structure.

If your costs are largely variable, then a margin of safety percentage of 20%–25% may be acceptable. This is because you are probably more able to scale down costs in slow periods. If you have many fixed costs, then it’s advisable to have a much higher minimum margin of safety percentage. In this instance, 50% is probably a bare minimum.

Ideally, aim for at least 70%–75%. For example, Company A has a margin of safety of 50%. This is calculated as follows.

(Actual Sales – Break-even Sales)	(£200,000 – £100,000) = £100,000
/Actual sales	/£200,000 = 0.5
* 100	50
Margin of safety (%)	50%

This is a comfortable figure if Company A has minimal fixed costs. If its sales decrease, it can probably take steps to scale back its variable costs. If, by contrast, Company A has many fixed costs, its margin of safety is relatively low. Ideally, it would look for ways to improve it.

How much is the margin of safety

What is Margin of Safety? – The margin of safety is the difference between the amount of expected profitability and the break-even point. The margin of safety formula is equal to current sales minus the breakeven point, divided by current sales.

What are the settings for transcutaneous pacing

Transcutaneous pacing modes Transcutaneous Pacing (TCP) is a temporary means of pacing a patient’s heart during an emergency and stabilizing the patient until a more permanent means of pacing is achieved. It is accomplished by delivering pulses of electric current through the patient’s chest, stimulating the heart to contract.

1. The most common indication for TCP is symptomatic bradycardia, most commonly resulting from acute MI, sinus node dysfunction, and complete heart block.
2. During TCP, pads are placed on the patient’s chest either in anterolateral position or anterior-posterior (AP) position.
3. The AP position is preferred because it minimizes transthoracic electrical impedance by sandwiching the heart between the two pads.

Current is applied until electrical capture (characterized by a wide QRS complex since the SA node-AV node conducting pathway is bypassed, with tall, broad T-waves on the EKG) occurs. In addition to synchronized TCP, there is an option for asynchronous TCP in cases of VF, VT, complete heart block.

Overdrive pacing is used to stop symptomatic tachydysrhythmias. Finally, do not be fooled by the monitor into believing that the appearance of QRS complexes means that the patient’s heart has been captured and is delivering a sustainable blood pressure! You need to have some way to tell that the heart is being paced and generating a blood pressure; have a pulse oximeter or arterial line waveform for confirmation of the monitor’s electrical activity.

Indications : Hemodynamically significant (hypotension, chest pain, pulmonary edema, altered mental status) bradydysrhythmias unresponsive to atropine, asystolic cardiac arrest (more likely to be successful when initiated early after a witnessed arrest–unwitnessed arrest seldom responds to transcutaneous pacing), failed intrinsic pacemaker.

1. When considering institution of transcutaneous pacing, always think about alternate causes for acute dysrhythmia, e.g.
2. Trauma, hypoxia, drug overdose, electrolyte imbalances and hypothermia.
3. Treat underlying cause.
4. Technique : Ideal pacer pad placement “sandwiches” the heart between the pacing pads and mimics the heart’s normal electrical axis.

Optimal placement for pads varies by manufacturer, but is generally anterior-posterior or anterior-lateral, with the former being most common. Begin at 10 milliamps and increase by increments of 10 until capture is noted. Target rate is generally 60-80 bpm.

• Strongly consider sedation, as external pacing can be quite uncomfortable.
• Most patients cannot tolerate currents of 50 milliamps and higher without sedation.
• Often 50-100 mA are required.
• Ideal current is 1.25x what was required for capture.
• Mechanical capture of the ventricles is evidenced by signs of improved cardiac output, including a palpable pulse, rise in blood pressure, improved level of consciousness, improved skin color and temperature.

Both electrical and mechanical capture must occur to benefit the patient. Pulses are difficult to palpate due to excessive muscular response. It is safe to touch patients (e.g. to perform CPR) during pacing. Pitfalls

Skeletal muscle contraction occurs at current levels as low as 10 milliamps, and does NOT suggest electrical or mechanical capture. Most common reason for not obtaining capture is not adequately increasing the current. Current should be increased as much as necessary for electrical capture. Undersensing: when a pacemaker fails to detect intrinsic activity, and therefore delivers a pace pulse. Oversensing is inappropriate inhibition of the pacemaker due to detection of signals other than R waves (e.g. muscle artifact). Pacing thresholds may change without warning and capture can readily be lost

: Transcutaneous pacing modes

What is the most common pacemaker setting

Modes and Codes – In order to standardize and facilitate the use and understanding of pacemakers, the North American Society for Pacing and Electrophysiology (NASPE) and British Pacing and Electrophysiology Group (NASPE/BPEG) groups devised the standard pacemaker codes, the NBG coding system.

• The most recent iteration of the NBG code was revised in 2002.
• The NBG code has five positions that denote pacemaker function; however, the last position is rarely used and will not be included in this discussion.
• In the context of the NBG code, “sensing” refers to the detection, by the pulse generator, of spontaneous cardiac depolarizations.

The effect of a “sensed” event is either a “triggered” pacing stimulus or an “inhibited” pacing stimulus. (Figure 11) Pacing and sensing. Position I refers to the chambers that are paced. “A” refers to atrium, “V” to ventricle, and “D” or “dual” to both the atrium and the ventricle. Position II refers to the chambers that are sensed. The letter codes are the same as above.

1. In addition, the letter “O” refers to a mode in which there is no sensing, in other words, asynchronous pacing.
2. Position III refers to the pulse generator’s response to a sensed event.
3. The letter “I” indicates that the pulse generator will inhibit a pacing stimulus in response to a sensed event.
4. The letter “T” indicates that the pulse generator will trigger a pacing stimulus in response to a sensed event.

The letter “D” is restricted to dual chamber systems and will both inhibit and trigger in response to sensed events. For example, a sensed event in the atrium will inhibit a pacing stimulus in the atrial channel, but triggers ventricular output. After the programmed AV delay, if the pulse generator senses a ventricular event, output will be inhibited in the ventricular channel.

1. If the pulse generator does not sense a ventricular event, then a pacing stimulus will be triggered.
2. The letter “O” indicates that there is no response to a sensed event and is most commonly used in the asynchronous pacing mode, as discussed below.
3. Position IV is unique in that it refers to the presence or absence of rate modulation or rate-adaptive pacing.

If present, the letter “R” indicates that that the pulse generator incorporates a sensor, which uses a variable—such as mechanical vibration, minute ventilation, or acceleration—to adjust the programmed paced heart rate in response to a patient’s activity.

1. If rate adaptive pacing is not used or is not available, rather than using the letter “O”, “R” is simply omitted.
2. Numerous factors must be considered when programming the pacing mode, such as the patient’s age, exercise capacity, chronotropic response, medical comorbidities, and the intrinsic cardiac rhythm.

To detail each pacing mode would be beyond the scope of this article; however, the examples of more commonly used modes are detailed below. VVI or VVIR: VVI(R) is one of the more commonly used pacing modes. VVI(R) is ventricular demand pacing. The ventricle is paced, sensed, and the pulse generator inhibits pacing output in response to a sensed ventricular event.

This mode of pacing prevents ventricular bradycardia and is primarily indicated in patients with atrial fibrillation with a slow ventricular response. However, since the pulse generator only paces and senses in the ventricle, there is loss of AV synchrony, which can potentially lead to pacemaker syndrome.

This mode of pacing is available in every pacemaker system that has a ventricular lead. AAI or AAI(R): AAI(R) is atrial demand pacing. The atrium is paced, sensed, and the pulse generator inhibits pacing output in response to a sensed atrial event. This mode is used for patients purely with sinus node dysfunction, yet maintain AV nodal function.

• This mode is being used in isolation uncommonly as the subsequent development of AV nodal conduction disease would render the patient vulnerable to bradycardia.
• This mode of pacing can be used in patients with dual chamber systems to minimize ventricular pacing along with an algorithm that can switch between AAI and DDD mode depending on sensed AV nodal conduction.

DDD or DDD(R): DDD or DDD(R) is a dual chamber system. It possesses pacing and sensing capabilities in both the atrium and the ventricle, and it is the most commonly used pacing mode. This mode is most appropriate for patients with combined sinus node dysfunction and AV nodal dysfunction.

Normal sinus rhythm (NSR) with no pacing (A sense, V sense). Atrial pacing with ventricular sensing and a native QRS (A pace, V sense). Atrial sensing with a native P wave and ventricular pacing (A sense, V pace). Atrial pacing and ventricular pacing (A pace, V pace).

The use of DDD(R) pacing mode in conjunction with an algorithm that minimizes ventricular pacing is preferred. Asynchronous modes, VOO or DOO: These are asynchronous pacing modes in which the pulse generator delivers a pacing stimulus at a fixed rate, without any sensing capabilities.

Therefore, the pacemaker is not “in sync” with the patient’s native rhythm and continues to deliver a pacing stimulus regardless of what the native conduction is doing. These modes are rarely used for extended periods of time. They are typically used when a pacemaker dependent patient is undergoing a surgical procedure that uses electrocautery that could be sensed by the pacemaker as native electrical conduction, which would inhibit pacemaker output and subsequently the patient could have profound bradycardia or even asystole.

There is a small possibility that pacing in an asynchronous mode could induce a pacing stimulus in the vulnerable period (on the T wave), which could potentially induce a lethal ventricular tachyarrhythmia.

What is transcutaneous pacemaker TCP?

Transcutaneous pacing Transcutaneous Pacing (TCP) is a temporary means of pacing a patient’s heart during an emergency and stabilizing the patient until a more permanent means of pacing is achieved. It is accomplished by delivering pulses of electric current through the patient’s chest, stimulating the heart to contract.

1. The most common indication for TCP is symptomatic bradycardia, most commonly resulting from acute MI, sinus node dysfunction, and complete heart block.
2. During TCP, pads are placed on the patient’s chest either in anterolateral position or anterior-posterior (AP) position.
3. The AP position is preferred because it minimizes transthoracic electrical impedance by sandwiching the heart between the two pads.

Current is applied until electrical capture (characterized by a wide QRS complex since the SA node-AV node conducting pathway is bypassed, with tall, broad T-waves on the EKG) occurs. In addition to synchronized TCP, there is an option for asynchronous TCP in cases of VF, VT, complete heart block.

Overdrive pacing is used to stop symptomatic tachydysrhythmias. Finally, do not be fooled by the monitor into believing that the appearance of QRS complexes means that the patient’s heart has been captured and is delivering a sustainable blood pressure! You need to have some way to tell that the heart is being paced and generating a blood pressure; have a pulse oximeter or arterial line waveform for confirmation of the monitor’s electrical activity.

Indications : Hemodynamically significant (hypotension, chest pain, pulmonary edema, altered mental status) bradydysrhythmias unresponsive to atropine, asystolic cardiac arrest (more likely to be successful when initiated early after a witnessed arrest–unwitnessed arrest seldom responds to transcutaneous pacing), failed intrinsic pacemaker.

When considering institution of transcutaneous pacing, always think about alternate causes for acute dysrhythmia, e.g. trauma, hypoxia, drug overdose, electrolyte imbalances and hypothermia. Treat underlying cause. Technique : Ideal pacer pad placement “sandwiches” the heart between the pacing pads and mimics the heart’s normal electrical axis.

Optimal placement for pads varies by manufacturer, but is generally anterior-posterior or anterior-lateral, with the former being most common. Begin at 10 milliamps and increase by increments of 10 until capture is noted. Target rate is generally 60-80 bpm.

• Strongly consider sedation, as external pacing can be quite uncomfortable.
• Most patients cannot tolerate currents of 50 milliamps and higher without sedation.
• Often 50-100 mA are required.
• Ideal current is 1.25x what was required for capture.
• Mechanical capture of the ventricles is evidenced by signs of improved cardiac output, including a palpable pulse, rise in blood pressure, improved level of consciousness, improved skin color and temperature.

Both electrical and mechanical capture must occur to benefit the patient. Pulses are difficult to palpate due to excessive muscular response. It is safe to touch patients (e.g. to perform CPR) during pacing. Pitfalls

Skeletal muscle contraction occurs at current levels as low as 10 milliamps, and does NOT suggest electrical or mechanical capture. Most common reason for not obtaining capture is not adequately increasing the current. Current should be increased as much as necessary for electrical capture. Undersensing: when a pacemaker fails to detect intrinsic activity, and therefore delivers a pace pulse. Oversensing is inappropriate inhibition of the pacemaker due to detection of signals other than R waves (e.g. muscle artifact). Pacing thresholds may change without warning and capture can readily be lost

: Transcutaneous pacing

Why are pacemaker set at 60 bpm?

Introduction – When Walton Lillehei and Earl Bakken pioneered the use of pacemakers for heart block following cardiac surgery, they reasoned that the programmed lower rate limit (LRL) should be set to a heart rate (HR) that the patient would be expected to have if conduction disease was not present.1 While the adult resting HR is known to average between 71 and 79 beats per minute (bpm), 2, 3 the expected resting HR for a given individual is not known.

Owing to the desire to limit dyssynchronous pacing from conventional pacing sites 4 and because a method to predict an individual’s resting HR is unknown, the pacemaker LRL is typically left at or near the factory setting of 60 bpm.5 This may not be the ideal backup pacing rate for all pacemaker-reliant patients.

The 60-bpm-fits-all approach dates back to an era before conduction system pacing—His bundle, left bundle, fascicular, and Bachmann bundle pacing—existed. With the potential to implant a fully physiologic pacing system, the pacemaker LRL could be customized without pacemaker-mediated dyssynchrony.

Recent evidence suggests that backup rates better approximating physiologic resting HRs benefit pacemaker-reliant patients with heart failure and a preserved ejection fraction (HFpEF) ( Supplemental Tables 1 and 2 ).6 In patients with HFpEF, atrial pacing to achieve a higher HR reduces cardiac filling pressures, whereas pharmacologic HR lowering increases filling pressures and worsens heart failure symptoms.6 Increasing the pacemaker LRL from 60 bpm to 80 bpm in patients with diastolic dysfunction and/or HFpEF improves quality of life, functional capacity, and NTproBNP levels, particularly in patients with a paced QRS 7 Rather than suggest an arbitrary lower rate target, we sought to identify a readily available metric to predict resting HR individualized to each person.

Although resting HR is influenced by many variables, 2, 3 we hypothesized that height could serve as a useful predictor and sought to better define the height–HR relationship. Height is a predictor of resting HR during the growing process 2, 8 and may also predict resting HR in adults.

What is the sensitivity setting on a pacemaker

Sensitivity and sensitivity threshold – The electrodes do not only pace, they also sense the electrical activity at the myocardial surface. One can define the sensitivity of a pacemaker electrode as the minimum myocardial voltage required to be detected as a P wave or R wave, measured in mV.

The sensitivity of the pacemaker is actually a setting on the box, where the lower the number, the more sensitive the pacemaker. The actual maximum sensitivity of the pacemaker is very high – when the electrode is freshly inserted, it can potentially detect very subtle changes in local electrical activity.

The general range of sensitivity for a normal pacemaker box is 0.4-10mV for the atria, and 0.8-20mV for the ventricles. However, to use maximal sensitivity settings could cause the pacemaker to mistake various random fluctuations of electrical activity for cardiac activity.

How do you initiate transcutaneous pacing ACLS?

Pads are On Now What? – Begin Transcutaneous pacing by connecting the patient to an ECG monitor to obtain a rhythm strip and confirm there is a rhythm which requires pacing. After placement of the pacing electrodes, connect the pacing cable to the electrodes and power on the device and set to “Pace” mode.

1. Next you will want to set the pacing rate.
2. Normally, the rate is set at a nonbradycardic rate between 60 and 80 beats per min.
3. Next the output or milliamperes needs to be adjusted and set.
4. You will increase the current slow and steady until electrical capture is achieved which is represented by a wide QRS and broad T wave.

Mechanical capture can be assessed by checking the pulses on the patient’s right upper extremity or right femoral pulse. Once electrical capture is achieved, adjust the pacing output or milliamperes just slightly above the level in which electrical capture was achieved.

What is min threshold and max threshold?

The minimum threshold, α0 is associated with the threshold at which there exist two components in the graph and the maximum threshold signifies a value above which the graph does not change much in terms of topology.

What does it mean pacemaker is working 100%?

There is 100 percent capture if the rhythm is entirely paced. However, there may be intermittent capture when the atrial pacemaker is in a demand mode and is activated only when the intrinsic atrial rate falls below a preset level.

What are examples of threshold values?

Working with Thre shold Values (WTHR) Purpose: Use this menu option to create statistics, such as tracking the number of held purchase orders, for the system to monitor. In this topic: • Updating Threshold Actual Values • Threshold Monitor Breach Email • System Delivered Thresholds • Work with Thresholds Screen • Create Threshold Values Screen Threshold values indicate the numbers and/or dollar values that trigger the system to generate an email when these values are breached.

1. Determining when a threshold is breached: For each threshold you define, the system compares the actual number value and/or dollar value for the threshold against the thresholds you define; and generates a Threshold Monitor Breach email if the threshold is breached.
2. The Comparison for the threshold determines when the threshold is breached.

If the comparison is: • Greater than : the threshold is breached when the actual number or dollar amount exceeds the threshold number or dollar amount. For example, the threshold is breached if the actual number is 241 and the threshold number is 200 (241 is greater than the threshold of 200).

• Less than : the threshold is breached when the actual number or dollar amount is less than the threshold number or dollar amount.
• For example, the threshold is breached if the actual dollar is $100 and the threshold dollar is $500 ($100 is less than $500).
• If you define both a threshold number value and a dollar value, the system checks both values to determine when the threshold is breached.

Example: One of the system-delivered thresholds is Backorders ( BO ). This threshold monitors the number of open and held orders that contain at least one unit on backorder, and monitors the merchandise dollars of units on backorder included on open or held orders.

1. You can use this threshold to send an email to the warehouse supervisor when there are more than 100 open and held orders that contain at least one unit on backorder.
2. To do so, define 100 as the threshold number with a greater than comparison (the actual value must be greater than the threshold value).

Once the actual number of open and held orders containing a backordered item is 101, the system sends an email to the warehouse supervisor.

Threshold Code and Description	Comparison	Number Value	Actual Number	Email address
BO : Backorders	Greater than (actual value is greater than the threshold value)	100	101	[email protected]

Updating Threshold Actual Values The System Delivered Thresholds are defined in the Threshold Value table. The Batch Order Control job ( ORD_CONTRL ) updates the actual threshold values and compares the threshold number value and/or threshold dollar value against the actual units and/or dollars for each threshold to determine if a threshold has been breached.

This job also updates the values in the Order Control Summary table. You can review order and merchandising summary information using the Operations Control Summary menu option. This menu option provides a high-level overview of the fulfillment process, identifies potential bottlenecks or problem areas, and delivers an audit trail of order activity.

See Reviewing Operations Control Summary (FLSH), Submitting the Batch Order Control job: The system submits the Batch Order Control job when: • you select Update current totals in the Operations Control Summary ( FLSH ) menu option; see Reviewing Operations Control Summary (FLSH),

• you submit a periodic process that: • includes the Order Summary ( ORDSUM ) periodic function (program name PFR0062 ), OR • includes the Threshold ( THRESHD ) periodic function (program name PFTHRESHMO ). Note: You can schedule a periodic process to run at a specified time; see Executing Periodic Processes (EPRO) for more information on defining a job schedule for a periodic process.

Batch Order Control processing: The Batch Order Control job: • updates all of the related fields in the Order Control Summary table for the current transaction date. You can review operations and merchandising summary values through the Reviewing Operations Control Summary (FLSH) menu option.

Generates the Operations Control Report, which lists the most recent operations and merchandising summary totals. Note: The system generates the report only if you submit the Batch Order Control job from the Operations Control Summary menu option or from the ORDSUM periodic function. • updates the actual value fields and Last updated fields in the Threshold Values table.

The system updates the actual value field regardless of whether you have defined a threshold. • determines if a threshold is breached by comparing the defined threshold number or dollar value against the actual number value and/or actual dollar value.

1. If you have not defined a threshold value for a threshold, the system does not monitor the threshold for a breach.
2. If a threshold has been breached, the system sends a Threshold Monitor Breach Email to the email address for the threshold.
3. Note: The system generates an email only if you submit the Batch Order Control job from the THRESHD periodic function.

Threshold Monitor Breach Email If a threshold is breached the system sends a Threshold Monitor Breach email to the email address for the threshold. Note: You can define just one email address for each threshold. See Email Address Validation for information on how the system verifies that your entry is formatted correctly.

Email hour interval: The system sends a threshold monitor breach email only when: • you submit the Batch Order Control job (see Updating Threshold Actual Values for more information on how to submit this job), and • the number of hours from the Email interval for the threshold has passed. The system compares the system date and system time to the Last sent on date field and Last sent on time for the threshold to determine whether to send another email, and continues to send an email based on the hourly interval until the threshold is no longer breached.

Sample email:

From:	[email protected]
To:	[email protected]
Subject:	**ALERT** Threshold Monitor Breach
Backorders threshold exceeded. Review Backorder Reports. Co#: 7 Actual$: 26973 > Thresh$: 13700 Use WTHR to monitor this breach.

Contents: • From: The system uses the following hierarchy to determine the from email address: • Company : If a From email address is specified for the company through Setting Up Companies (WCMP), use this address; otherwise, • System : Use the from.email specified through Setting up the Email Properties File, • To: The Email address for the breached threshold. • Subject: **ALERT** Threshold Monitor Breach • First data: Indicates which threshold has been breached, for example: Backorders threshold exceeded, • Second data: The text from the Action field for the breached threshold. • Third data: The company, actual threshold value, and threshold comparison value defined for the breached threshold, for example: Co#: 7 Actual$: 26973 > Thresh$: 13700, • Final data: Use WTHR to monitor this breach, System Delivered Thresholds The table below describes the system-delivered thresholds and how the system updates the threshold actual values. If have not already created these thresholds, the Batch Order Control job automatically creates them; however, you still need to define the threshold criteria; see Updating Threshold Actual Values,

Code	Name	Threshold Description
AP	A/P Balance	Monitors the open accounts payable balance, including all outstanding (unpaid) A/P invoices, across all vendors. This total is negative if the dollar total of credits is greater than the dollar total of unpaid invoices. Actual dollar value The Open A/P balance from the Order Control Summary table for the most recent transaction date.
AR	A/R balance	Monitors the open accounts receivable balance, including all open, allocated, or disputed open items across all bill-to accounts. This total is negative if the dollar total of credits is greater than the dollar total of open invoices. Actual dollar value The Open A/R balance from the Order Control Summary table for the most recent transaction date.
BO	Backorders	Monitors the number of open and held orders that contain at least one unit on backorder, and the total merchandise dollar value of these backordered units. The system determines if an item is on backorder by calculating open quantity on order line – reserved quantity on order line = backorder quantity, The system determines the open quantity by calculating order quantity – shipped quantity – cancelled quantity – soldout quantity = open quantity, Actual number value The total number of open and held orders that contain at least one unit on backorder, including the total number of ship-to addresses for orders with multiple ship-tos. For example, an order with two ship-to addresses updates the number of orders total by 2. This is the sum of the Future use 1 number and Future use 2 number from the Order Control Summary table for the most recent transaction date. Actual dollar value The sum of the Open backordered dollars and the Held backordered dollars from the Order Control Summary table for the most recent transaction date.
HP	Purchase Orders On Hold	Monitors the number of held purchase orders and the merchandise dollar value of items on these purchase orders. Held purchase orders are POs that are in a held ( H ) status; this does not include recurring POs or drop ship POs. The PO line status can be open ( O ) or held ( H ) to be included in these totals. Actual number value The Held PO number from the Order Control Summary table for the most recent transaction date. Actual dollar value The merchandise dollar total for held purchase orders from the PO Detail table, determined by subtracting the quantity received from the quantity ordered and multiplying by the PO price. This is the Held PO dollars from the Order Control Summary table for the most recent transaction date.
IB	Inventory On Backorder	Monitors the number of units on backorder that are on open or held orders and the total merchandise dollars of backordered units on these orders. Actual number value The sum of the Open quantity backordered and Held quantity backordered from the Order Control Summary table for the most recent transaction date. Actual dollar value The sum of the Open dollars backordered and the Held dollars backordered from the Order Control Summary table for the most recent transaction date.
IP	Inventory Pending Putaway	Monitors the number of units received into a pending putaway warehouse and their merchandise dollar value. A pending putaway warehouse is a warehouse where you place inventory that is on its way to its final destination. You can define a warehouse as a pending putaway warehouse by assigning a warehouse location type of PP (pending putaway warehouse) to the warehouse in Working with Default Warehouse Locations (WWDL), The system increases these totals when you receive a PO line or a partial quantity on a PO line into a pending putaway warehouse. Actual number value The total number of units received into a pending putaway warehouse, from the Pending Putaway Detail table. This is the Pending putaway quantity from the Order Control Summary table for the most recent transaction date.
		Actual dollar value The merchandise dollar value of items received into a pending putaway warehouse, from the Pending Putaway Detail table. The system multiplies the quantity pending for each pending putaway detail record by the PO cost to determine the merchandise dollar value for each pending putaway detail record (if a PO cost is not defined, the system uses the SKU cost from the SKU table). The system then sums the merchandise dollars for each pending putaway detail record to determine the total pending putaway merchandise dollars. This is the Pending putaway dollars from the Order Control Summary table for the most recent transaction date.
IS	Inventory In Staging Whs	Monitors the number of units received into a staging warehouse and the merchandise dollars value of these units. A staging warehouse is a warehouse that represents an area within your actual warehouse where you keep stock that needs to be put away. You can designate a warehouse as a staging warehouse by entering the warehouse code in the Default Staging Warehouse (E15) system control value. The system increases these totals when you receive a PO line or a partial quantity on a PO line into a staging warehouse. Actual number value The total number of units received into a staging warehouse. To determine the number of units received into staging, the system totals the on-hand quantity for each item warehouse record in the staging warehouse. This is the Staging inventory quantity from the Order Control Summary table for the most recent transaction date. Actual dollar value The merchandise dollar value of items received into a staging warehouse. To determine the merchandise dollars of items received into staging, the system multiplies the total on-hand quantity in the Item Warehouse table for the staging warehouse times the SKU cost. This is the Staging inventory dollars from the Order Control Summary table for the most recent transaction date.
LP	LTD purchase dollars	Monitors the number of orders placed by a sold-to customer and their merchandise dollar value. The system monitors this threshold only when the sold-to customer places an order in order entry. If the Update Demand for Order Maintenance Transactions (C72) system control value is selected, the system increases a sold-to customer’s LTD (life-to-date) orders number and dollars when you add an order line to an order in order maintenance. The system reduces a sold-to customer’s LTD orders number and dollars when you cancel an order if the cancel reason you enter is set to update demand. Note: You must manually create this threshold value. Also, the threshold’s actual number and actual value are not listed on the Work with Thresholds Screen since these values apply to a specific sold to customer. The system does not send an email when this threshold is breached; instead, a pop-up window opens in order entry. Customer Order History Window The Customer Order History Window opens in order entry when you enter an order for a customer whose LTD order dollars exceeds the threshold value. Actual number value The number of orders placed by a sold-to customer, not including any returns created through order entry, exchange items entered on an order, or order including a gift certificate but no merchandise. This is the Order number LTD in the Customer Sold To Order History table for the most recent transaction date. Actual dollar value The merchandise dollar value of the orders placed by a sold-to customer, including any backordered or soldout items and the purchase of any gift certificates, but not including any returns created through order entry. This is the Order dollars LTD from the Customer Sold To Order History table for the most recent transaction date.
NP	Orders Rsvd/Not Printed	Monitors the number of reserved units on open and held orders and their total merchandise dollar value. Actual number value The sum of the Open unprinted quantity and Held unprinted quantity from the Order Control Summary table for the most recent transaction date. Actual dollar value The sum of the Open unprinted dollars and Held unprinted dollars from the Order Control Summary table for the most recent transaction date.
OH	Orders On Hold	Monitors the number of units on held orders and their total merchandise dollar value. This includes units regardless of whether they are on backorder or are printed, but does not include held order lines if the order itself is not held. Actual number value The sum of the Held backordered quantity, Held printed quantity, and Held Unprinted quantity from the Order Control Summary table for the most recent transaction date. Actual dollar value The sum of the Held backordered dollars, Held printed dollars, and Held unprinted dollars from the Order Control Summary table for the most recent transaction date.
OR	Pending Refund	Monitors the number of pending refunds and their total merchandise dollar value. Pending refunds are refunds in an open or held status that have not yet been processed; these totals do not include refunds that are in a pending cancelled, cancelled, pending write off, write off, or processed status. Actual number value The Refunds pending number from the Order Control Summary table for the most recent transaction date. Actual dollar value The Refunds pending dollars from the Order Control Summary table for the most recent transaction date.
PC	Pending RA Credit	Monitors the number of pending return authorization credits and their total merchandise dollar value. Pending return authorization credits are return authorizations that have been received, but not yet credited. These totals include the returned units on return and exchange transactions, but not items ordered in exchange. Actual number value The total number of pending return authorization credits, regardless of whether the returns are on the same order. For example, an order with 2 pending RA credit order lines processed separately updates this total by 2; however, if the same 2 pending RA credit order lines on a single order are processed in the same transaction, the total updates by 1. The system determines the number of pending RA credits by totaling the number of RA header records whose date received is greater than 0 and date credited is 0. This is the Pending RA credit number from the Order Control Summary table for the most recent transaction date. Actual dollar value The merchandise dollar total of items on pending return authorization credits, determined by multiplying the uncredited quantity by the order detail price. From the Pending RA credit dollars in the Order Control Summary table for the most recent transaction date.
PD	Purchase Orders Past Due	Monitors the number of purchase orders that contain purchase order lines that are past due their merchandise dollar value. This does not include drop ship purchase orders. Past due purchase orders contain PO lines that have not yet been received and are past the expected due date (the Due date on the PO line is earlier than the current date). PO lines whose status is open ( O ) or held ( H ) are included in these totals. Actual number value The total number of open, held, and docked POs that include PO lines that are past due. This is the sum of the Open past due PO number, Held past due PO number, and Docked past due PO number from the Order Control Summary table for the most recent transaction date. Actual dollar value The merchandise dollar total for items on open, held, and docked POs that are past due. This is the sum of the Open past due PO dollars, Held past due PO dollars, and Docked past due PO dollars from the Order Control Summary table for the most recent transaction date.
PK	Purchase Orders Docked	Monitors the number of docked purchase orders and their merchandise dollar value. Docked purchase orders are POs that are in a docked ( D ) status. PO lines on partially docked PO’s whose status is ( O ) or held ( H ) are included in these totals. If you partially receive a docked PO, the system updates the PO status from docked ( D ) to open ( O ). Actual number value The Docked PO number from the Order Control Summary table for the most recent transaction date. Actual dollar value The merchandise dollar total for docked purchase orders from the PO Detail table, determined by subtracting the quantity received from the quantity ordered and then multiplying by the PO price. This is the Docked PO dollars from the Order Control Summary table for the most recent transaction date.
PO	Pending Pick Slips	Monitors the number of pending pick slips and their merchandise dollar value. Pending pick slips are pick slips that have not yet been billed, but does not include pick slips that are voided, waiting for authorization, or suspended. The system increases the pending pick slip number, units, and dollars for drop ship orders if the drop ship output defined for the vendor is drop ship pick slip; if the drop ship output defined for the vendor is drop ship purchase order or collaborative shipping, the system increases the total units and total dollars pending, but does not increase the total number pending. Actual number value The Pending picks number from the Order Control Summary table for the most recent transaction date. Actual dollar value The Open printed dollars and Held printed dollars from the Order Control Summary table for the most recent transaction date.
RA	Pending RA Receipt	Monitors the number of pending return authorization receipts and their merchandise dollar value. Pending return authorization receipts are return authorizations that have been entered, but not yet received. These totals include items returned on return and exchange transactions, not items ordered in exchange. Actual number value The total number of pending RA receipts, regardless of whether the returns are on the same order. For example, an order with 2 pending RA receipt order lines processed separately updates this total by 2; however, if the same 2 pending RA receipt order lines on a single order are processed in the same transaction, the total updates by 1.
		The system determines the number of pending RA receipts by totaling the number of RA header records whose date received is 0. This is the Pending RA receipt number from the Order Control Summary table for the most recent transaction date. Actual dollar value The merchandise dollar total of items on pending return authorization receipts, determined by multiplying the unreceived quantity by the order detail price. This is the Pending RA receipt dollars from the Order Control Summary table for the most recent transaction date.
RS	Suspended PO Receipts	Monitors the number of PO lines received into suspense and their merchandise dollar value. Actual number value The total number of PO lines received into suspense, including PO lines that have a partial quantity received into suspense. This is the Suspense receipts number from the Order Control Summary table for the most recent transaction date. Actual dollar value The S uspense receipts dollars from the Order Control Summary table for the most recent transaction date.
SB	Suspended Batches	Monitors the total number of order batches that are in a suspended status. The system does not monitor a threshold dollar value for suspended batches. Actual number value The system determines the number of order batches in a suspended status by totaling the number of orders in the Order Batch table whose Batch suspended field is set to Y, This is the Batches suspended number from the Order Control Summary table for the most recent transaction date.
SI	Suspended Inventory	Monitors the number of units received into suspense and their merchandise dollar value. Actual number value The Suspense receipts quantity from the Order Control Summary table for the most recent transaction date. Actual dollar value The Suspense receipts dollars from the Order Control Summary table for the most recent transaction date.
SO	Suspended Orders	Monitors the number of suspended orders and their merchandise dollar value, regardless of whether the order is batched. Actual number value The total number of suspended orders, from the number of orders in a suspended status or error status in the Order Header table. This is the Orders suspended number in the Order Control Summary table for the most recent transaction date. Actual dollar value The merchandise dollar total of suspended orders, including orders in a suspended or error status. This is the sum of the merchandise dollars for suspended and orders in error in the Order Ship To table. This is the Orders suspended dollars from the Order Control Summary table for the most recent transaction date.
VC	Virtual Card Numbers	Monitors the number of stored value card numbers available to assign to a virtual stored value card. Actual number value The actual number of records in the Virtual Card Number Table (FLSVCA),

Work with Thresholds Screen Purpose: Use this screen to review, create, change, or submit a command to process a threshold value. How to display this screen: Enter WTHR in the Fast path field at the top of a menu or select Work with Threshold Values from a menu.

Field	Description
Description	A description of the threshold. See System Delivered Thresholds for a listing of system-delivered threshold values and the calculations performed. Alphanumeric, 30 positions; optional.
Threshold units	The number defined for the threshold. Numeric, 7 positions; display-only.
Threshold value	The dollar amount defined for the threshold. Note: You can enter a whole dollar amount, but no decimals. Numeric, 7 positions; display-only.
Breached values are highlighted in red: A threshold’s Actual units or Actual value, or both, are highlighted in red if they have breached the corresponding thresholds. The system considers a threshold breached if you have specified a Comparison setting for the threshold and either of the actual values is beyond the threshold, even if the threshold is zero. For example, if you have set the Comparison for A/R Balance to Greater than and left the threshold value and $ value as zero, then the A/R Balance is considered breached if either the actual units or value are greater than zero. To avoid having a threshold flagged as breached, set the Comparison to unselected (blank).
Actual units	The actual current value for the threshold, such as the actual number of units on backorder. Numeric, 7 positions; display-only.
Actual value	The actual dollar amount for the threshold, such as the dollar value of units on backorder. Note: The system rounds the actual dollar amount down to the nearest whole dollar. Numeric, 7 positions; display-only.
Action	The message to include in the Threshold Monitor Breach Email to indicate the action to take if the threshold is breached; for example, if the OH (Orders on Hold) threshold is breached, the action may be GENERATE THE HELD ORDERS REPORT, Alphanumeric, 50 positions; display-only.

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Screen Option Procedure Create a threshold Select Create to advance to the Create Threshold Values Screen, Change a threshold Select Change next to a value to advance to the Change Threshold Values screen. At this screen you can change all fields except the Last update date and time, Threshold code, Actual unit value, Actual dollar value, and Last sent date and time, See Create Threshold Values Screen for field descriptions. Delete a threshold Select Delete next to a value to delete it. Display a threshold Select Display next to a value to advance to the Display Threshold Values screen. You cannot change any information on this screen. See Create Threshold Values Screen for field descriptions. Show all thresholds or only breached thresholds Select Show All/Breached, The system toggles between displaying all thresholds or only those thresholds that have been breached. When is a threshold considered breached? The system considers a threshold breached if you have specified a Comparison setting for the threshold and either of the actual values is beyond the threshold, even if the threshold is zero. For example, if you have set the Comparison for A/R Balance to Greater than and left the threshold value and $ value as zero, then the A/R Balance is considered breached if either the actual units or value are greater than zero. To avoid having a threshold flagged as breached, set the Comparison to unselected (blank).

Create Threshold Values Screen Purpose: Use this screen to create a threshold. How to display this screen: Select Create at the Work with Thresholds Screen,

Field	Description
Threshold	The code and description that represents a threshold. See System Delivered Thresholds for a list of system-delivered thresholds. Threshold code: Alphanumeric 2 positions. Create screen: required. Change screen: display-only. Threshold description: Alphanumeric, 30 positions; required.
Last update	The date and time when the threshold was last updated. Date: Alphanumeric, 6 positions; display-only. Time: Alphanumeric, 6 positions; display-only.
Comparison	Defines how the system determines whether the threshold is breached. Valid values: • Greater than = The threshold is breached when the actual system value exceeds the threshold value. • Less than = The threshold is breached when the actual system value is less than the threshold value. Note: Leave this field blank (unselected) if you do not want the system to check whether the threshold is breached. Optional.
Value	The number that represents the threshold value. Numeric, 7 positions; optional.
$ Value	The dollar amount the represents the threshold value. Note: You can only enter a whole dollar amount. Numeric, 9 positions with a 2-place decimal; optional.
Actual value	The actual number for this threshold, updated by the system. Example: The actual number of units on backorder. Numeric, 7 positions; display-only.
$ actual value	The actual dollar amount for this threshold, updated by the system. Example: The dollar value of units on backorder. Note: The system rounds the actual dollar amount down to the nearest whole dollar. Numeric, 9 positions with a 2-place decimal; display-only.
Email address	The email address where the system delivers the Threshold Monitor Breach Email when the threshold is breached. Note: You can define just one email address for each threshold. See Email Address Validation for information on how the system verifies that your entry is formatted correctly. Alphanumeric, 50 positions; optional.
Email interval	The number of hours the system waits before sending another email for the breached threshold. Numeric, 3 positions; optional.
Last sent on/at	The last date and time when an email was sent for the threshold. Date: numeric, 6 positions (MMDDYY format); display-only. Time: numeric, 6 positions (HHMMSS format); display-only.
Action	The message to include in the Threshold Monitor Breach Email, indicating the action to take if the threshold has been breached; for example, if the OH (Orders on Hold) threshold is breached, the action may be GENERATE THE HELD ORDERS REPORT, Alphanumeric, 50 positions; optional.
Code	A code for the application area associated with the threshold. Alphanumeric, 3 positions; required.
Group code	A code for the application group associated with the threshold. Alphanumeric, 3 positions; required.

What is the pulse amplitude of a pacemaker?

Stimulation threshold – As previously discussed, myocardium may be excited by external electrical stimuli that drive the cells to threshold. Stimulation threshold is the minimum amount of energy required to reach threshold and evoke an action potential,

• The intensity of the electrical stimulus is described by its amplitude (measured in volts) and duration (measured in milliseconds).
• The amplitude and duration of the pulse must be optimized to ensure depolarization while minimizing battery consumption.
• Amplitudes are normally below 1.5 V and pulse duration (width) is usually set to 0.5 ms.

The relationship between current (I), voltage (V) and resistance (R) is described by Ohm’s law: V = I • R Pacemakers generate a constant voltage (V). The current that is delivered by the pulse generator can be calculated as follows: I = V/R Given that voltage (V) is constant and battery depletion must be minimized, most pacemakers use lead tips with high resistance (400 to 1200 Ω).

What are the factors affecting pacing threshold?

1–8) Pacemaker implantation allows the use of anti-arrhythmic drugs for patients with bradycardia. However, pacing threshold is sometimes increased by the anti-arrhythmic drugs. Factors affecting pacing threshold are posture, exercise, diet, sleep, minerals, pH, hormones, auto- nomic tones, and underlying diseases.

Why is it important to check the pacing threshold?

Abstract – Because it determines the “reserve” of the pacemaker’s output circuit, threshold measurement remains the single most important factor that will ultimately ensure successful pacing. In this review, we describe the various techniques and significance of threshold measurement in relation to the property of pacemaker output circuits.

• There are two basic types of pacing circuits: (1) those with constant current, as in most external (temporary) pulse generators, and (2) those with constant voltage, as in many implantable pulse generators.
• Current-limited pulse generators have features of both constant-current and constant-voltage circuitry.

The current threshold is helpful in determining the integrity of the electrode-tissue interface and reflects the density of the current, which is the prime factor responsible for successful stimulation. Voltage thresholds are useful for information on lead position and integrity, especially when voltage and current are measured simultaneously.

Impedance (calculated from voltage and current during stimulation) can be helpful in the diagnosis of lead fractures, insulation breaks, and position problems. Threshold and impedance are entirely unrelated factors, each providing specific and different information about a pacing system. Threshold may also be measured in terms of charge and energy and in relation to the width of the pulse (at a constant impulse amplitude).

The concept of safety margins is important when measuring long-term threshold at the time of replacement of a pulse generator. We have analyzed this problem and have attempted to make acceptable recommendations in the absence of clear information in the literature about this subject.

What factors affect pacing threshold?

1–8) Pacemaker implantation allows the use of anti-arrhythmic drugs for patients with bradycardia. However, pacing threshold is sometimes increased by the anti-arrhythmic drugs. Factors affecting pacing threshold are posture, exercise, diet, sleep, minerals, pH, hormones, auto- nomic tones, and underlying diseases.