IMPORTANT #'s to Know

Interpeak Interval or Duration of 60 Hz

16.6 msec or .016 /sec

hand washing

20 sec

Eye or Skin Flush with Sodium Hypochlorite Irritation

15 sec

differential impedance of amplifier

≥ 100 megohms

Time (horizontal) Resolution of Amplifier

≤ 20 μs/data point

Filter Capabilities of the EP System

0.1 - 5,000 Hz

Noise Level of the Amplifier

≤ 2 µV rms

Chassis Leakage Current-EP Machine

≤ 100 µA

≤ .0001 AMP

≤ .1 mA

chassis leakage current electrodes/leads

≤ 10 µA rms

chassis leakage current check frequency

Twice Per Year

Semi-Annually = BEST choice

Biannually

Waveform Replication Criteria Clinical EP

1 % Latency

15 % Amplitude

Morphology

Average Amplitude of BAEP

0.5 µV

Broad Band Click Frequency

2,000-4,000 Hz

earliest wave I can occur

1.4 msec

Earliest Wave III can occur

3.5 msec

Earliest Wave V can occur

5.5 msec

BAEP Headphone/Insert Earphone Calibration

Twice Per Year

Semi-Annually

Biannually

normal hearing

0-20 dB HL

criteria for normal hearing

2.5-3.0 standard deviations from mean

BAEP Adult Values (Latency/Amplitude)

36 months

BAEP Adult Configuration/Morphology

3-6 months

BAEP Alarm Criteria

1 msec or more > in WV

MN surgery levels

C1-C6

UN surgery levels

C7-C8

PTN surgery levels

T1 and below

SSEP amplitude range

0.1 µV & 10 µV

SSEP alarm criteria

increase of 10% or greater in latency; decrease of 50% or greater in amplitude

EPIDURAL SSEP Filter Settings

300 Hz - 3,000 Hz

EPIDURAL SSEP Latency of Response

19-25 msec

EPIDURAL SSEP Number of Averages

50 Averages

sensorimotor cortex mapping filters

1-30 Hz to 250-1,500 Hz (-3 dB)

sensorimotor cortex mapping number of averages

25-50 Averages

sensorimotor cortex mapping amplitudee

200 - 500 uV

sensorimotor cortex mapping pre-central gyrus

P22-N25

sensorimotor cortex mapping post-central gyrus

N20-P23

A-D converter size minimum

8 bit

A-D converter size BEST

16 bit

common mode rejection ratio minimum

10,000 to 1 or 80 dB

common mode rejection ratio at 120 dB

1,000,000 to 1

Acceptable Ratio of High to Low frequency Filter Setting

100:1

recommended signal to noise ratio

2:1

artifact rejection criteria

Amplifier Rejects signals which exceed 90 - 98 % of the full range of the A-D Convertor

microshock level

< 100 uV

CPR compression to breaths ratio

30:2

Contact Time To Disinfect a Non-critical Item (combs, tape measures)

30-60 sec

Contact Time To Disinfect a Semi-Critical Item (reusable scalp electrodes) or Critical Item (Creutzfeld Jacob Electrodes) !High Level Sterilization!!

submersed 10-30 min depending on disinfectant

disinfectants must be marked with what 3 pieces of info?

1) date of shelf expiration

2) date of uncapping

3) date of discard

sodium hypochlorite (bleach) concentration

5.25%

sodium hypochlorite (bleach) shelf life UNopened

1 year

sodium hypochlorite (bleach) shelf life uncapped/opened

4 months

high level sterilization (scalp electrodes and CJD electrodes) sodium hypochlorite concentration

1:10

1 cup bleach to 9 cups water

high-level sterilization (scalp electrodes and CJD electrodes) sodium hypochlorite immersion time

20 min MINIMUM

Mixed Sodium Hypochlorite Expiration for Use

24 hours

Time labs must save archived MSDS sheets after last employee has used or item was in lab

30 years

mask use for TB

N95

Particle Reduction (Epithelial Cells\Skin Cells) when Wearing Scrubs

10,000 parts per minute to 3,000 parts per minute

MINIMUM distance a non-sterile person remains from a sterile person

12 in

Upper SSEP Obligate Peak Which Validates Elective Hypothermia

P14

latency of response to stimulation of trigeminal nerve

5 msec

latency of response to stimulation of facial nerve

7 msec

BAEP Changes with Neurofibromotosis Type II

Increased I-III & I-V

(Acoustic Neuroma)

Bandpass Cranial Nerve Monitoring Free Run EMG

10-30 Hz to 16,000 Hz

Bandpass Cranial Nerve Monitoring Evoked EMG (Surgeon Stim in Field)

1-250 Hz to 1,500 Hz

cranial nerve threshold of exposed nerve

0.1-0.5 uV

extraocular muscles

CN III, IV, VI

how many cranial nerves are sensory only

3

how many cranial nerves are motor only

5

how many cranial nerves are mixed

4

criteria for well placed pedicle screw

CMAP Above 10 mA

recording electrodes for TceMEP

C1 and C2

delta frequency

0-4 Hz

theta frequency

4-7 Hz

alpha frequency

8-13 Hz

beta frequency

13-30 Hz

gamma frequency

25-100 Hz

40 Hz = MOST common

defines depth of anesthesia

Filter & Sensitivity Setting For EEG

Sensitivity: 7µV/mm

Bandpass: 1-70 Hz

Time, After Carotid Clamping, Changes Occur

< one minute

Alarm Criteria Carotids

≥ 50 DECREASE in Fast Activity

≥ INCREASE in SLOW Delta Activity

Target Burst to Suppression Ratio of EEG in Aneurysm Surgery

1:4 or 1:5

during functional mapping (epilepsy surgery) threshold of motor strip

2-5 milliamps (mA)

during functional mapping (epilepsy surgery) threshold of language area

8-15 milliamps

Degree Ketamine & Etomidate > Cortical SSEP Amplitude

5-10 fold

MAC of Halothane (Fluothane)

0.77%

MAC Enflurane (Ethrane)

1.7%

MAC of Isoflurane (Forane)

1.15%

MAC of Sevoflurane (Altane)

1.71%

MAC of Desflurane (Suprane)

6%

MAC of nitrous oxide

120%

Amount of Gas Needed to Attenuate Cortical SSEPs

1 MAC without N2O

½ MAC with N2O

Vecuronium (Norcuron) length of action

40-60 minutes

Rocuronium (Zemuron) length of action

40-60 minutes

Pancuronium (Pavulon) length of action

60 minutes (longest acting)

Succinylcholine length of action

3-5 minutes (shortest acting)

Train of Four

0/4

1/4

2/4

3/4

4/4

100% relaxed

90% relaxed

50% relaxed

25% relaxed

0% relaxed

resting membrane potential of cell

-70mV

Nyquist frequency

the sampling rate should be at least two times the highest frequency

normal body temp

37 degrees C

MOST hypothermic body temp

Lowest Number Below 37 Degrees C

normal BP

120/80 - 140/90 mmHg

systolic pressure which may attenuate evoked potentials

lowest number in mmHg