{{Infobox comorbidity
| other_names =
| anesthetic_relevance = High
| anesthetic_management = Preoperative HgA1c value
Preoperative glucose value
Preoperative medication adjustment
Insulin administration
Post-operative glucose
| specialty = Endocrine
| signs_symptoms = Excessive thirst
Polyuria
Polydypsia
Glucosuria
Peripheral neuropathy
Ocular degeneration
Cardiovascular disease
| diagnosis = HgA1c
Fasting glucose
| treatment = Oral anti-hyperglycemics
Exogenous insulin administration
| image =
| caption =
}}'''Diabetes''' is an endocrine, metabolic disorder marked by high levels of blood glucose. Three classifications of diabetics exist:

#[[Type 1 Diabetes]], where an immune mediated destruction of pancreatic beta cells occurs causing a total reduction in endogenous insulin and thus causing hyperglycemia
#[[Type II Diabetes]], where patients experience increasing insulin resistance for the level of endogenous insulin thus causing hyperglycemia
# [[Gestational Diabetes]] in which hyperglycemia occurs in the second or third trimester of pregnancy.

The diagnosis of diabetes is made based on fasting blood glucose levels and hemoglobin A1c levels. The diabetic population in the United States is both increasing in incidence and prevalence within the last decade. This disease affects multiple organ systems that have anesthetic implications including cardiovascular health, renal disease, peripheral neurologic function, and gastrointestinal emptying requiring preoperative optimization and intraoperative control.

Cystic fibrosis patients have an acquired form of diabetes as the most common co-morbidity of cystic fibrosis (20% of adolescents and 40-50% of adults).<ref>{{Cite journal|last=Association|first=American Diabetes|date=2021-01-01|title=2. Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes—2021|url=https://care.diabetesjournals.org/content/44/Supplement_1/S15|journal=Diabetes Care|language=en|volume=44|issue=Supplement 1|pages=S15–S33|doi=10.2337/dc21-S002|issn=0149-5992|pmid=33298413}}</ref>

==Anesthetic implications==

===Preoperative optimization===

* No overt indications for case cancellations for poorly controlled diabetes<ref>{{Cite journal|last=Vann|first=Mary Ann|date=2014-06|title=Management of Diabetes Medications for Patients Undergoing Ambulatory Surgery|url=https://linkinghub.elsevier.com/retrieve/pii/S1932227514000226|journal=Anesthesiology Clinics|language=en|volume=32|issue=2|pages=329–339|doi=10.1016/j.anclin.2014.02.008}}</ref><ref>{{Cite journal|last=Joshi|first=Girish P.|last2=Chung|first2=Frances|last3=Vann|first3=Mary Ann|last4=Ahmad|first4=Shireen|last5=Gan|first5=Tong J.|last6=Goulson|first6=Daniel T.|last7=Merrill|first7=Douglas G.|last8=Twersky|first8=Rebecca|date=2010-12|title=Society for Ambulatory Anesthesia Consensus Statement on Perioperative Blood Glucose Management in Diabetic Patients Undergoing Ambulatory Surgery:|url=http://journals.lww.com/00000539-201012000-00009|journal=Anesthesia & Analgesia|language=en|volume=111|issue=6|pages=1378–1387|doi=10.1213/ANE.0b013e3181f9c288|issn=0003-2999}}</ref> except if patients are in diabetes ketoacidosis (DKA) or hyperosmolar osmotic non-ketotic crisis (HONK)
* Postoperative blood glucose greater than 140 mg/dL is found in as many as 40% of patient undergoing non-cardiac surgery and almost 25% of those patients demonstrate a blood glucose greater than 180 mg/dL during the operative and immediate post-operative period<ref>{{Cite journal|last=Frisch|first=A.|last2=Chandra|first2=P.|last3=Smiley|first3=D.|last4=Peng|first4=L.|last5=Rizzo|first5=M.|last6=Gatcliffe|first6=C.|last7=Hudson|first7=M.|last8=Mendoza|first8=J.|last9=Johnson|first9=R.|last10=Lin|first10=E.|last11=Umpierrez|first11=G. E.|date=2010-08-01|title=Prevalence and Clinical Outcome of Hyperglycemia in the Perioperative Period in Noncardiac Surgery|url=http://care.diabetesjournals.org/cgi/doi/10.2337/dc10-0304|journal=Diabetes Care|language=en|volume=33|issue=8|pages=1783–1788|doi=10.2337/dc10-0304|issn=0149-5992|pmc=PMC2909062|pmid=20435798}}</ref><ref>{{Cite journal|last=Levetan|first=C. S.|last2=Passaro|first2=M.|last3=Jablonski|first3=K.|last4=Kass|first4=M.|last5=Ratner|first5=R. E.|date=1998-02-01|title=Unrecognized Diabetes Among Hospitalized Patients|url=http://care.diabetesjournals.org/cgi/doi/10.2337/diacare.21.2.246|journal=Diabetes Care|language=en|volume=21|issue=2|pages=246–249|doi=10.2337/diacare.21.2.246|issn=0149-5992}}</ref>
* Data shows mixed reduction of mortality with good blood glucose control in surgical patients<ref>{{Cite journal|last=Buchleitner|first=Ana Maria|last2=Martínez-Alonso|first2=Montserrat|last3=Hernández|first3=Marta|last4=Solà|first4=Ivan|last5=Mauricio|first5=Didac|date=2012-09-12|editor-last=Cochrane Metabolic and Endocrine Disorders Group|title=Perioperative glycaemic control for diabetic patients undergoing surgery|url=https://onlinelibrary.wiley.com/doi/10.1002/14651858.CD007315.pub2|journal=Cochrane Database of Systematic Reviews|language=en|doi=10.1002/14651858.CD007315.pub2}}</ref>, but a reduction in surgical site infection risk<ref>{{Cite journal|last=Kroin|first=Jeffrey S.|last2=Buvanendran|first2=Asokumar|last3=Li|first3=Jinyuan|last4=Moric|first4=Mario|last5=Im|first5=Hee-Jeong|last6=Tuman|first6=Kenneth J.|last7=Shafikhani|first7=Sasha H.|date=2015-06|title=Short-Term Glycemic Control Is Effective in Reducing Surgical Site Infection in Diabetic Rats:|url=http://journals.lww.com/00000539-201506000-00018|journal=Anesthesia & Analgesia|language=en|volume=120|issue=6|pages=1289–1296|doi=10.1213/ANE.0000000000000650|issn=0003-2999}}</ref>
* Consider case delay alongside surgery team if BG > 250 mg/dL and case is elective and a prothesis or synthetic biofilm will be inserted into the patient during surgery (i.e. prothesis, intraocular lens, joint replacement, graft, etc).
* Obtain pre-operative HgA1c if one has not been obtained via primary care in last 3 months prior to surgery
** If HgA1c > 8.0 - evidence shows greater incidence of post-operative hyperglycemia during patient recovery

===== Pre-operative medication adjustments: =====
{| class="wikitable"
|+
!Drug Class
!Medication
!Day before Surgery
!Day of surgery
!Notes
|-
|DPP-4 inhibitors
|Sitagliptin/Saxagliptin
lidagliptin/linagliptin
|Take
|Take
|
|-
|Alpha-glucosidase
inhibitors
|Acarbose/Miglitol
|Take
|Do not take
|
|-
|Sulfonylureas
|Glipizide/glyburide
|Take
|Do not take
|
|-
|SGLT-2 inhbitors
|dapagliflozin/canagliflozin
empagliflozin
|Hold 3 days prior
to surgery<ref name=":0">{{Cite journal|last=Research|first=Center for Drug Evaluation and|date=2021-01-11|title=FDA revises labels of SGLT2 inhibitors for diabetes to include warnings about too much acid in the blood and serious urinary tract infections|url=https://www.fda.gov/drugs/drug-safety-and-availability/fda-revises-labels-sglt2-inhibitors-diabetes-include-warnings-about-too-much-acid-blood-and-serious|journal=FDA|language=en}}</ref>
|Do not take
|Can cause euglycemic DKA<ref name=":1">{{Cite journal|last=Seger|first=Christian D.|last2=Xing|first2=Hanning|last3=Wang|first3=Libing|last4=Shin|first4=John S.|date=2021-01-14|title=Intraoperative Diagnosis of Sodium-Glucose Cotransporter 2 Inhibitor–Associated Euglycemic Diabetic Ketoacidosis: A Case Report|url=https://journals.lww.com/10.1213/XAA.0000000000001380|journal=A&A Practice|language=en|volume=15|issue=1|pages=e01380|doi=10.1213/XAA.0000000000001380|issn=2575-3126}}</ref> if not stopped in advance of surgery
|-
|SGLT-2 inhibitors
|ertugliflozin
|Hold 4 days prior
to surgery<ref name=":0" />
|Do not take
|Can cause euglycemic DKA<ref name=":1" /> if not stopped in advance of surgery
|-
|Biguanides
|metformin/Metformin ER
|Take
| +/- take
|Hold if patient has renal/hepatic insufficiency, COPD or CHF or if
team anticipates potential for AKI or hepatic shock during case
|-
|GLP-1 agonist
|exenatide/exenatide ER
|Take
|Do not take
|
|-
|GLP-1 agonist
|dulaglutide
|Take
|Do not take
|
|-
|GLP-1 agonist
|semaglutide
|Take
|Do not take
|
|-
|GLP-1 agonist
|liraglutide
|Take
|Do not take
|
|-
|Amylin mimetics
|pramlintide
|Take
|Do not take
|
|-
|
|
|
|
|
|-
|Long acting insulin
|Glargine/detemir/degludec
|Take 80% of dose
|Take 80% of dose
|Coordinate with patient's endocrinologist
|-
|U-500 insulin
|
|Take usual dose
|Take 50% of dose
|Coordinate with patient's endocrinologist
|-
|70/30 insulin
|
|Take usual dose
|Change to NPH
and give 50% of dose
|Coordinate with patient's endocrinologist
|-
|70/25 insulin
|
|Take usual dose
|Change to NPH
and give 50% of dose
|Coordinate with patient's endocrinologist
|-
|50/50 insulin
|
|Take usual dose
|Change to NPH
and give 50% of dose
|Coordinate with patient's endocrinologist
|-
|NPH insulin
|
|Take usual dose
|Take 50% of dose
|Coordinate with patient's endocrinologist
|-
|Prandial insulin
|
|Take usual mealtime dose
|Do not take
|Coordinate with patient's endocrinologist
|-
|Insulin pump
|
|
|Set at 80% basal rate
|Coordinate with patient's endocrinologist
|}

===Intraoperative management===
Institutional practices may vary, however the general principle is to perform close monitoring and maintain euglycemia. Stanford intraoperative glycemic care guidelines recommend targeting a blood glucose of 140-180 during surgery<ref name=":2">{{Cite web|title=Intraoperative Glycemic Care Guidelines|url=https://ether.stanford.edu/policies/Intraoperative%20Glycemic%20Care%20Guidelines%20and%20appendix.pdf|url-status=live}}</ref>. An interval of q2h is appropriate if the patient's blood glucose remains within this range. Sugars between 70-140 warrant closer q1h monitoring, and any sugar below 70 in most adult patients necessitates treatment with a dextrose bolus (e.g. 12.5 g of D50) with subsequent q15 min glucose checks.

For patients with hyperglycemia >180, the duration of surgery and level of critical illness can guide whether intermittent subcutaneous insulin vs continuous insulin infusion is appropriate for intraoperative management. Subcutaneous insulin (e.g. Humalog a.k.a. Lispro) is delivered every 2-3 hours based on a sliding scale (cannot be delivered more frequently due to the time to peak effect of insulin and risk of dose stacking). Continuous insulin infusions are generally titrated every hour with at minimum a rate of 0.5 units/hour running unless glucose levels fall below 100 mg/dL. Subcutaneous insulin management is not appropriate for patients with poor perfusion or those who have no change in glucose after 2 attempted doses.

=== Postoperative management===
Continue sliding scale/insulin pump management post-operatively.

==Related surgical considerations ==
Certain factors can predispose patients to being either insulin-sensitive or insulin-resistant intra-operatively. Factors that are associated with insulin-sensitivity include: new diagnosis; age >70 years old; BMI <25 kg/m2, eGFR <45 mL/min. Factors that are associated with insulin-resistance include: BMI >35 kg/m2; home TDD >80 units; steroids >20 mg prednisone/day<ref name=":2" />.

==Pathophysiology ==
Correctional dosing of insulin is based off of a patients total daily dose (TDD). This may already be known based off of a patients home regimen. For patients whose TDD is unknown, an adult's TDD can be approximated as 0.4U/kg/day<ref name=":2" />.

From a patient's TDD, an insulin sensitivity factor (ISF) can be calculated that provides a patient's corrective dosing (i.e. the expected drop in glucose if a patient is given 1U of rapid-acting insulin).

ISF = 1800/TDD

As an example, a patient with a TDD of 48U will have an ISF of 37.5 (which can be rounded to 40). Therefore, one possible corrective dosing regimen could be 1U for every 40 >180 (assuming target glucose of 180).

==Signs and symptoms ==
Intra-operatively, hypoglycemia can lead to cardiac arrhythmia and hemodynamic instability. Hyperglycemia has been shown to increase adverse post-surgical outcomes including surgical site infections, delayed wound healing, and increased length of stay<ref>{{Cite web|url=https://pubs.asahq.org/anesthesiology/article/126/3/547/19751/Perioperative-Hyperglycemia-ManagementAn-Update|access-date=2022-08-03|website=pubs.asahq.org}}</ref>.

==Diagnosis==
Diagnosis of diabetes can be made by a variety of ways:

# Fasting plasma glucose ≥ 126mg/dL
# Two-hour plasma glucose ≥ 200mg/dL
# A1C ≥ 6.5 prior to initiating anti-hyperglycemic medications

==Treatment==

===Medication===
Humalog (Lispro) is a rapid-acting agent commonly used in sliding scale regimens. It's onset occurs in <15 minutes. Its peak occurs in 30-90 minutes. Duration is generally between 3-5 hours (which is why dosing is performed no more frequently than every 2-3 hours).

Long acting agents include glargine (Basaglar/Lantus) and are typically dosed once a day in the evening as part of a home insulin regimen.

==Epidemiology==
The diabetic population in the United States is both increasing in incidence and prevalence within the last decade. According to the 2017 National Diabetes Statistics Report from the Center for Disease Control (CDC), 10.5% of the U.S. population has diabetes with an estimated 21.4% of those who have the disease are still not diagnosed.<ref>{{Cite web|date=2020-09-28|title=National Diabetes Statistics Report, 2020 {{!}} CDC|url=https://www.cdc.gov/diabetes/data/statistics-report/index.html|access-date=2021-07-12|website=www.cdc.gov|language=en-us}}</ref>

==References==

<references />

[[Category:Comorbidities]]

2022-08-03T01:21:24Z

Bsumida1:

Opioid use disorder

2022-08-03T01:10:34Z

Bsumida1:

2022-07-10T16:16:04Z

Bsumida1:

Posterior spinal fusion

2022-07-10T15:10:40Z

Bsumida1: Created page with "{{Infobox surgical procedure | anesthesia_type = | airway = | lines_access = | monitors = | considerations_preoperative = | considerations_intraoperative = | considerations_postoperative = }} Posterior spinal fusion is an orthopedic procedure performed to correct idiopathic scoliosis. It is the most common treatment for idiopathic scoliosis. It involves implants (an array of hooks, screws, and wires) being attached to segments of spine. Harrington rods were the o..."

Autonomic dysreflexia

2022-07-05T01:57:52Z

Bsumida1: Added 2 references, pathophys section

{{Infobox comorbidity
| other_names = Mass reflex
| anesthetic_relevance = Critical
| anesthetic_management = Consider neuraxial or MAC 
If GA, run deep
| specialty = Neurology, Cardiology
| signs_symptoms = Hypertension 
Headache 
Diaphoresis 
Bradycardia or tachycardia
| diagnosis = Most common with lesions above T6.
Has been described in lesions as low as T10
| treatment = Rapidly titratable vasodilators
Deepen anesthesia
| image =
| caption =
}}'''Autonomic dysreflexia''' is potentially life threatening sympathetic hyperactivity in patients with spinal cord injury which can emerge in response to noxious or non-noxious stimulation below the level of injury. Autonomic dysreflexia typically occurs in patients with lesions at or above T6, but has been reported in injuries as low as T10.<ref>{{Cite journal|last=Vallès|first=M.|last2=Benito|first2=J.|last3=Portell|first3=E.|last4=Vidal|first4=J.|date=2005|title=Cerebral hemorrhage due to autonomic dysreflexia in a spinal cord injury patient|url=https://pubmed.ncbi.nlm.nih.gov/16010281|journal=Spinal Cord|volume=43|issue=12|pages=738–740|doi=10.1038/sj.sc.3101780|issn=1362-4393|pmid=16010281|via=}}</ref>

==Anesthetic implications==

===Preoperative optimization ===
Preoperative history is essential in alerting the anesthesiologist to the possibility of intraoperative AD. Key information includes the spinal cord injury history (timing, degree of injury and importantly the level), prior history of autonomic dysreflexia and associated triggers (if known).

The planned procedure also significantly impacts the likelihood of intraoperative AD. Stimulus above the injury level are less likely to provoke autonomic dysreflexia while injuries below are higher risk.

===Intraoperative management===
An anesthetic plan can include general or neuraxial techniques for patients at risk.

If general anesthesia is chosen, patients should be kept at a sufficiently deep level of anesthesia to prevent dysreflexia. Fast acting agents that can quickly be titrated are preferred such as Propofol and the insoluble volatile anesthetics.

Neuraxial anesthesia may be used, especially a spinal which can effectively prevent the development of autonomic dysfunction. However, limitations include difficulty determining the level of spinal block. Epidural anesthesia is less effective than spinal anesthesia for patients with SCI but can be considered.

For patients with no sensation at the surgical site and with injury below T6, MAC is an acceptable option. <ref>{{Cite web|last=Mathews|first=Letha|date=May 2021|title=Anesthesia for adults with chronic spinal cord injury|url=https://www.uptodate.com/contents/anesthesia-for-adults-with-chronic-spinal-cord-injury|url-status=live|archive-url=|archive-date=|access-date=2021-06-18|website=www.uptodate.com}}</ref>

Goal is to maintain mean arterial pressure within 20 to 25 percent of patient's baseline.

===Postoperative management===
Minimize potential triggers of AD such as post op bladder distention

==Related surgical procedures==
Most common surgical stimulus includes distention of hollow viscus, most commonly urinary bladder distention.

==Pathophysiology==
Impairment of autonomic regulation due to high spinal cord injury leads to sympathetic over-reactivity. Likely, there are synaptic changes post spinal cord injury (e.g. reduced gliosis) which may contribute to impaired regulation. The result is an uninhibited sympathetic response to stimuli causing hypertension due to splanchnic and peripheral vasoconstriction. Uninjured spinal cord above the level of injury counters with a parasympathetic response which is unable to adequately regulate blood pressure but does result in a response in heart rate (i.e. bradycardia).

Injuries below the level of T6 generally do not result in autonomic dysreflexia due to intact innervation/regulation of the splanchnic circulation.

== Signs and symptoms==
Sympathetic hyperreactivity below the lesion presents with vasoconstriction (pale, dry skin), systemic hypertension and associated headache. Parasympathetic hyperreactivity above the lesion presents with vasodilation, flushing, piloerection, miosis, nausea, and vomiting. Awake patients may also endorse lightheadedness, anxiety, and sensation of doom.

Vital sign changes consistent with AD include severe hypertension and bradycardia. Hypertension can evolve to end organ dysfunction including pulmonary edema, left ventricular dysfunction, intracranial hemorrhage, seizures or even death. Bradycardia may also range from asymptomatic to sinus arrest.

Of note, it is important to note patient's baseline resting blood pressure which may be lower in the setting of spinal cord injury (to assess for relative hypertension). This is important in early identification of AD<ref>{{Cite journal|last=Bycroft|first=J.|last2=Shergill|first2=I. S.|last3=Chung|first3=E. a. L.|last4=Choong|first4=E. a. L.|last5=Arya|first5=N.|last6=Shah|first6=P. J. R.|date=2005-04|title=Autonomic dysreflexia: a medical emergency|url=https://pubmed.ncbi.nlm.nih.gov/15811886/|journal=Postgraduate Medical Journal|volume=81|issue=954|pages=232–235|doi=10.1136/pgmj.2004.024463|issn=0032-5473|pmc=1743257|pmid=15811886}}</ref>.

==Treatment==

===Medication ===
Management of hypertension

* Deepen level of anesthesia, consider Mac-BAR
* If epidural, re-dose
* Fast-acting titratable agents:
** Nitroprusside infusion (0.2 to 10 mcg/kg/minute)or nitroglycerin infusion (5 mcg/minute to 200 to 500 mcg/minute)
** Nicardipine 0.2 to 0.5 mg IV bolus with nicardipine infusion (2.5 to 15 mg/hour)
** Consider labetalol, however bradycardia usually contraindicates beta blockade

====== Management of bradycardia: ======

* Atropine or glycopyrrolate

=== Surgery===
Stop causative stimulus – Communication with surgical team to pause surgery with the goal of limiting continued noxious stimulus while hemodynamics are addressed

==Epidemiology==
AD usually develops within the first year after spinal cord injury. It has been reported in anywhere between 20-70% of patients with injury above the level of T6<ref>{{Cite journal|last=Helkowski|first=Wendy M.|last2=Ditunno|first2=John F.|last3=Boninger|first3=Michael|date=2003|title=Autonomic dysreflexia: incidence in persons with neurologically complete and incomplete tetraplegia|url=https://pubmed.ncbi.nlm.nih.gov/14997966/|journal=The Journal of Spinal Cord Medicine|volume=26|issue=3|pages=244–247|doi=10.1080/10790268.2003.11753691|issn=1079-0268|pmid=14997966}}</ref>.

==References==

[[Category:Comorbidities]]

<references />
[[Category:Neurologic disorders]]

Neuromuscular blockade

2022-07-04T11:45:06Z

Bsumida1:

'''Neuromuscular blockade''' involves the use of neuromuscular blocking agents (NMBAs) (i.e. paralytics) to facilitate endotracheal intubation and/or surgical procedures.

==Drugs used==
'''Non-depolarizing agents''' bind to and INHIBIT acetylcholine receptors at the end plate of the neuromuscular junction. Common examples below include:

''Steroidal non-depolarizing agents'' (hepatic and/or renal excreted):

* Rocuronium
* Vecuronium

''Benzylisoquinolinium non-depolarizing agents'' (broken down by Hoffman Elimination):

* Cisatrocurium (the cis-enantiomer of atrocurium)

'''Depolarizing agents''' on the other hand bind and ACTIVATE acetylcholine receptors causing sustained depolarization of the neuromuscular junction (i.e. muscle contraction) followed by paralysis. The prototypical example being:

* Succinylcholine
Depolarizing agents have different implications for neuromuscular blockade monitoring as discussed below.

==Monitoring==
===Train of Four===
'''Equipment (Quantitative Monitoring)'''

In order to assess the level of paralysis during an anesthesia event, train of four monitoring (either quantitative or qualitative) is typically used throughout the duration of the procedure (e.g. during routine assessments) and prior to extubation. Quantitative train of four monitoring is the most accurate assessment of neuromuscular blockade and is preferred as it mitigates the risk of residual paralysis and subsequent post-op pulmonary complications<ref>{{Cite web|last=Brull|first=Sorin|title=Current Status of Neuromuscular Reversal and Monitoring: Challenges and Opportunities|url=https://pubs.asahq.org/crawlprevention/governor?content=%2fanesthesiology%2farticle%2f126%2f1%2f173%2f660%2fCurrent-Status-of-Neuromuscular-Reversal-and|url-status=live|access-date=2022-07-03|website=pubs.asahq.org}}</ref>. Equipment that can be used includes:

* Electromyography (EMG)
* Acceleromyography (AMG)
* Kinemyography (KMG)

These monitors calculate a train of four ratio (TOFR) which the provider uses to determine the depth of paralysis. This ratio is the magnitude of the 4th twitch divided by the magnitude of the 1st twitch. A higher ratio indicates lighter paralysis. Prior to extubation, for example, providers look for a TOFR of at least >0.9 indicating almost complete recovery of muscle strength/function.

All of the above involve the stimulation of peripheral nerves, the differences being what is actually measured. EMG measures evoked muscle responses (a.k.a. action potentials). AMG measures the acceleration of thumb contraction using Newton's Second Law of Motion (Force = Mass x Acceleration). KMG uses mechanosensors that generate measurable electrical signals. All are valid for use in quantitative train of four monitoring. AMG and KMG require unrestricted motion of the hand or muscle interrogated while EMG does not. AMG and KMG are also subject to the phenomenon of "reverse fade." EMG on the other hand can be affected by electrical interference in the operating room (cautery) but nonetheless is usually the monitoring device of choice.

'''Qualitative Monitoring'''

In lieu of EMG, providers may also use a nerve stimulator and palpate for muscle contraction in order to assess depth of paralysis. This is less accurate and generally overestimates recovery from paralysis<ref>{{Cite journal|last=Azizoğlu|first=Mustafa|last2=Özdemir|first2=Levent|date=2021-08-01|title=Quantitative Neuromuscular Monitoring With Train-of-Four Ratio During Elective Surgery: A Prospective, Observational Study|url=https://pubmed.ncbi.nlm.nih.gov/34276037/|journal=Journal of Patient Safety|volume=17|issue=5|pages=352–357|doi=10.1097/PTS.0000000000000874|issn=1549-8425|pmid=34276037}}</ref>. The risk of this is residual paralysis which contributes to higher rates of post-op pulmonary complications.

'''Methods of assessment'''

''Train of Four Count (TOFC)''

Electrical stimulus is applied to a peripheral nerve and the number of twitches counted corresponds to the amount/percent of acetylcholine receptors blocked:

1 twitch = >95%

2 twitches = 85-90%

3 twitches = 80-85%

4 twitches = 70-75%

When administering reversal drugs, TOFC is used to determine readiness or dosing of medication.

* If using Neostigmine/Glycopyrrolate: generally given when TOFC is 4

* If using Sugammadex: 4 mg/kg for 1-2 twitches, 2 mg/kg for 3-4 twitches, 16 mg/kg for immediate reversal

''Post Tetanic Count (PTC)''

With PTC, a large 50 Hz stimulus is applied for 5 seconds followed by subsequent 1 Hz stimuli over 20 seconds. PTC is used when the TOFC is zero. PTC can indicate time to recovery (e.g. a PTC of 1 indicates recovery from paralysis in approximately 30 minutes).

'''Sites of Use (for helpful graphics, can refer to [https://www.uptodate.com/contents/monitoring-neuromuscular-blockade/print UpToDate]'''<ref>{{Cite web|title=UpToDate|url=https://www.uptodate.com/contents/monitoring-neuromuscular-blockade/print|access-date=2022-07-03|website=www.uptodate.com}}</ref>)

''Ulnar Nerve''

Generally the preferred site of monitoring. It is easily accessible. There is a lower chance of direct muscle stimulation which is not an assessment of nerve function/neuromuscular blockade. If surgical positioning interferes with intraoperative monitoring, can consider measuring closer to the end of the case if able to access the limb at that time.
''Facial Nerve''
''Facial Nerve''

''Facial Nerve''

May be necessary depending on surgical positioning, however is prone to more inaccuracies due to direct muscle stimulation. The palpated muscles may either be the orbicularis occuli (which generally correlates with diaphragm and larynx recovery) as well as the geniohyoid muscle (upper airway recovery).
''Posterior Tibial Nerve''
''Posterior Tibial Nerve''

''Posterior Tibial Nerve''

Generally used with AMG.

'''Fade'''

Fade is the progressive decrease in amplitude in response to nerve stimulation as a result of increased levels of paralysis. This is important as twitches are counted until the provider appreciates a significant drop in amplitude. It is difficult to assess twitches/fade when the TOFR is >0.4 (which is still a significant paralysis).

Of note, fade is generally not observed when depolarizing agents such as succinylcholine are used (instead, there is a uniform decrease in amplitude). Fade may still be observed with depolarizing agents if patients are in phase II of paralysis where there is desensitization of the neuromuscular junction after prolonged acetylcholine channel opening.

==Reversal Methods (with dosing)==

===Traditional Agents===
'''Glycopyrrolate''' (given first to prevent bradycardia): 0.1-0.2 mg/kg IV

'''Neostigmine:''' 0.03-0.07 mg/kg IV (max 5 mg)

=== <big>Newer Agents</big> ===
'''Sugammadex:''' 4 mg/kg for 1-2 twitches, 2 mg/kg for 3-4 twitches, 16 mg/kg for immediate reversal

Considerations for Sugammadex include the risk of arrhythmias, hypersensitivity reactions (increased with larger doses). Although there is concern with the use of Sugammadex in patients with kidney dysfunction (as it is renally cleared), recent studies have shown its safe use in patients with end stage renal disease (ESRD)<ref>{{Cite journal|last=Paredes|first=Stephania|last2=Porter|first2=Steven B.|last3=Porter|first3=Ivan E.|last4=Renew|first4=J. Ross|date=2020-12|title=Sugammadex use in patients with end-stage renal disease: a historical cohort study|url=https://pubmed.ncbi.nlm.nih.gov/32949009/|journal=Canadian Journal of Anaesthesia = Journal Canadien D'anesthesie|volume=67|issue=12|pages=1789–1797|doi=10.1007/s12630-020-01812-3|issn=1496-8975|pmid=32949009}}</ref>.

==References==

[[Category:Drug reference]]

Neuromuscular blockade

2022-07-04T11:43:42Z

Bsumida1:

'''Neuromuscular blockade''' involves the use of neuromuscular blocking agents (NMBAs) (i.e. paralytics) to facilitate endotracheal intubation and/or surgical procedures.

==Drugs used==
'''Non-depolarizing agents''' bind to and INHIBIT acetylcholine receptors at the end plate of the neuromuscular junction. Common examples below include:

''Steroidal non-depolarizing agents'' (hepatic and/or renal excreted):

* Rocuronium
* Vecuronium

''Benzylisoquinolinium non-depolarizing agents'' (broken down by Hoffman Elimination):

* Cisatrocurium (the cis-enantiomer of atrocurium)
'''Depolarizing agents''' on the other hand bind and ACTIVATE acetylcholine receptors causing sustained depolarization of the neuromuscular junction (i.e. muscle contraction) followed by paralysis. The prototypical example being:

'''Depolarizing agents''' on the other hand bind and ACTIVATE acetylcholine receptors causing sustained depolarization of the neuromuscular junction (i.e. muscle contraction) followed by paralysis. The prototypical example being:

* Succinylcholine
Depolarizing agents have different implications for neuromuscular blockade monitoring as discussed below.

==Monitoring==
===Train of Four===
'''Equipment (Quantitative Monitoring)'''

In order to assess the level of paralysis during an anesthesia event, train of four monitoring (either quantitative or qualitative) is typically used throughout the duration of the procedure (e.g. during routine assessments) and prior to extubation. Quantitative train of four monitoring is the most accurate assessment of neuromuscular blockade and is preferred as it mitigates the risk of residual paralysis and subsequent post-op pulmonary complications<ref>{{Cite web|last=Brull|first=Sorin|title=Current Status of Neuromuscular Reversal and Monitoring: Challenges and Opportunities|url=https://pubs.asahq.org/crawlprevention/governor?content=%2fanesthesiology%2farticle%2f126%2f1%2f173%2f660%2fCurrent-Status-of-Neuromuscular-Reversal-and|url-status=live|access-date=2022-07-03|website=pubs.asahq.org}}</ref>. Equipment that can be used includes:

* Electromyography (EMG)
* Acceleromyography (AMG)
* Kinemyography (KMG)

These monitors calculate a train of four ratio (TOFR) which the provider uses to determine the depth of paralysis. This ratio is the magnitude of the 4th twitch divided by the magnitude of the 1st twitch. A higher ratio indicates lighter paralysis. Prior to extubation, for example, providers look for a TOFR of at least >0.9 indicating almost complete recovery of muscle strength/function.

All of the above involve the stimulation of peripheral nerves, the differences being what is actually measured. EMG measures evoked muscle responses (a.k.a. action potentials). AMG measures the acceleration of thumb contraction using Newton's Second Law of Motion (Force = Mass x Acceleration). KMG uses mechanosensors that generate measurable electrical signals. All are valid for use in quantitative train of four monitoring. AMG and KMG require unrestricted motion of the hand or muscle interrogated while EMG does not. AMG and KMG are also subject to the phenomenon of "reverse fade." EMG on the other hand can be affected by electrical interference in the operating room (cautery) but nonetheless is usually the monitoring device of choice.

'''Qualitative Monitoring'''

In lieu of EMG, providers may also use a nerve stimulator and palpate for muscle contraction in order to assess depth of paralysis. This is less accurate and generally overestimates recovery from paralysis<ref>{{Cite journal|last=Azizoğlu|first=Mustafa|last2=Özdemir|first2=Levent|date=2021-08-01|title=Quantitative Neuromuscular Monitoring With Train-of-Four Ratio During Elective Surgery: A Prospective, Observational Study|url=https://pubmed.ncbi.nlm.nih.gov/34276037/|journal=Journal of Patient Safety|volume=17|issue=5|pages=352–357|doi=10.1097/PTS.0000000000000874|issn=1549-8425|pmid=34276037}}</ref>. The risk of this is residual paralysis which contributes to higher rates of post-op pulmonary complications.

'''Methods of assessment'''

''Train of Four Count (TOFC)''

Electrical stimulus is applied to a peripheral nerve and the number of twitches counted corresponds to the amount/percent of acetylcholine receptors blocked:

1 twitch = >95%

2 twitches = 85-90%

3 twitches = 80-85%

4 twitches = 70-75%

When administering reversal drugs, TOFC is used to determine readiness or dosing of medication.

* If using Neostigmine/Glycopyrrolate: generally given when TOFC is 4

* If using Sugammadex: 4 mg/kg for 1-2 twitches, 2 mg/kg for 3-4 twitches, 16 mg/kg for immediate reversal

''Post Tetanic Count (PTC)''

With PTC, a large 50 Hz stimulus is applied for 5 seconds followed by subsequent 1 Hz stimuli over 20 seconds. PTC is used when the TOFC is zero. PTC can indicate time to recovery (e.g. a PTC of 1 indicates recovery from paralysis in approximately 30 minutes).

'''Sites of Use (for helpful graphics, can refer to [https://www.uptodate.com/contents/monitoring-neuromuscular-blockade/print UpToDate]'''<ref>{{Cite web|title=UpToDate|url=https://www.uptodate.com/contents/monitoring-neuromuscular-blockade/print|access-date=2022-07-03|website=www.uptodate.com}}</ref>)

''Ulnar Nerve''

Generally the preferred site of monitoring. It is easily accessible. There is a lower chance of direct muscle stimulation which is not an assessment of nerve function/neuromuscular blockade. If surgical positioning interferes with intraoperative monitoring, can consider measuring closer to the end of the case if able to access the limb at that time.
''Facial Nerve''
''Facial Nerve''

''Facial Nerve''

May be necessary depending on surgical positioning, however is prone to more inaccuracies due to direct muscle stimulation. The palpated muscles may either be the orbicularis occuli (which generally correlates with diaphragm and larynx recovery) as well as the geniohyoid muscle (upper airway recovery).
''Posterior Tibial Nerve''
''Posterior Tibial Nerve''

''Posterior Tibial Nerve''

Generally used with AMG.

'''Fade'''

Fade is the progressive decrease in amplitude in response to nerve stimulation as a result of increased levels of paralysis. This is important as twitches are counted until the provider appreciates a significant drop in amplitude. It is difficult to assess twitches/fade when the TOFR is >0.4 (which is still a significant paralysis).

Of note, fade is generally not observed when depolarizing agents such as succinylcholine are used (instead, there is a uniform decrease in amplitude). Fade may still be observed with depolarizing agents if patients are in phase II of paralysis where there is desensitization of the neuromuscular junction after prolonged acetylcholine channel opening.

==Reversal Methods (with dosing)==

===Traditional Agents===
'''Glycopyrrolate''' (given first to prevent bradycardia): 0.1-0.2 mg/kg IV

'''Neostigmine:''' 0.03-0.07 mg/kg IV (max 5 mg)

=== <big>Newer Agents</big> ===
'''Sugammadex:''' 4 mg/kg for 1-2 twitches, 2 mg/kg for 3-4 twitches, 16 mg/kg for immediate reversal

Considerations for Sugammadex include the risk of arrhythmias, hypersensitivity reactions (increased with larger doses). Although there is concern with the use of Sugammadex in patients with kidney dysfunction (as it is renally cleared), recent studies have shown its safe use in patients with end stage renal disease (ESRD)<ref>{{Cite journal|last=Paredes|first=Stephania|last2=Porter|first2=Steven B.|last3=Porter|first3=Ivan E.|last4=Renew|first4=J. Ross|date=2020-12|title=Sugammadex use in patients with end-stage renal disease: a historical cohort study|url=https://pubmed.ncbi.nlm.nih.gov/32949009/|journal=Canadian Journal of Anaesthesia = Journal Canadien D'anesthesie|volume=67|issue=12|pages=1789–1797|doi=10.1007/s12630-020-01812-3|issn=1496-8975|pmid=32949009}}</ref>.

==References==

[[Category:Drug reference]]

Neuromuscular blockade

2022-07-04T11:42:43Z

Bsumida1:

'''Neuromuscular blockade''' involves the use of neuromuscular blocking agents (NMBAs) (i.e. paralytics) to facilitate endotracheal intubation and/or surgical procedures.

==Drugs used==
'''Non-depolarizing agents''' bind to and INHIBIT acetylcholine receptors at the end plate of the neuromuscular junction. Common examples below include:

''Steroidal non-depolarizing agents'' (hepatic and/or renal excreted):

* Rocuronium
* Vecuronium

''Benzylisoquinolinium non-depolarizing agents'' (broken down by Hoffman Elimination):

* Cisatrocurium (the cis-enantiomer of atrocurium)

'''Depolarizing agents''' on the other hand bind and ACTIVATE acetylcholine receptors causing sustained depolarization of the neuromuscular junction (i.e. muscle contraction) followed by paralysis. The prototypical example being:

* Succinylcholine
Depolarizing agents have different implications for neuromuscular blockade monitoring as discussed below.

==Monitoring==
===Train of Four===
'''Equipment (Quantitative Monitoring)'''

In order to assess the level of paralysis during an anesthesia event, train of four monitoring (either quantitative or qualitative) is typically used throughout the duration of the procedure (e.g. during routine assessments) and prior to extubation. Quantitative train of four monitoring is the most accurate assessment of neuromuscular blockade and is preferred as it mitigates the risk of residual paralysis and subsequent post-op pulmonary complications<ref>{{Cite web|last=Brull|first=Sorin|title=Current Status of Neuromuscular Reversal and Monitoring: Challenges and Opportunities|url=https://pubs.asahq.org/crawlprevention/governor?content=%2fanesthesiology%2farticle%2f126%2f1%2f173%2f660%2fCurrent-Status-of-Neuromuscular-Reversal-and|url-status=live|access-date=2022-07-03|website=pubs.asahq.org}}</ref>. Equipment that can be used includes:

* Electromyography (EMG)
* Acceleromyography (AMG)
* Kinemyography (KMG)

These monitors calculate a train of four ratio (TOFR) which the provider uses to determine the depth of paralysis. This ratio is the magnitude of the 4th twitch divided by the magnitude of the 1st twitch. A higher ratio indicates lighter paralysis. Prior to extubation, for example, providers look for a TOFR of at least >0.9 indicating almost complete recovery of muscle strength/function.

All of the above involve the stimulation of peripheral nerves, the differences being what is actually measured. EMG measures evoked muscle responses (a.k.a. action potentials). AMG measures the acceleration of thumb contraction using Newton's Second Law of Motion (Force = Mass x Acceleration). KMG uses mechanosensors that generate measurable electrical signals. All are valid for use in quantitative train of four monitoring. AMG and KMG require unrestricted motion of the hand or muscle interrogated while EMG does not. AMG and KMG are also subject to the phenomenon of "reverse fade." EMG on the other hand can be affected by electrical interference in the operating room (cautery) but nonetheless is usually the monitoring device of choice.

'''Qualitative Monitoring'''

In lieu of EMG, providers may also use a nerve stimulator and palpate for muscle contraction in order to assess depth of paralysis. This is less accurate and generally overestimates recovery from paralysis<ref>{{Cite journal|last=Azizoğlu|first=Mustafa|last2=Özdemir|first2=Levent|date=2021-08-01|title=Quantitative Neuromuscular Monitoring With Train-of-Four Ratio During Elective Surgery: A Prospective, Observational Study|url=https://pubmed.ncbi.nlm.nih.gov/34276037/|journal=Journal of Patient Safety|volume=17|issue=5|pages=352–357|doi=10.1097/PTS.0000000000000874|issn=1549-8425|pmid=34276037}}</ref>. The risk of this is residual paralysis which contributes to higher rates of post-op pulmonary complications.

'''Methods of assessment'''

''Train of Four Count (TOFC)''

Electrical stimulus is applied to a peripheral nerve and the number of twitches counted corresponds to the amount/percent of acetylcholine receptors blocked:

1 twitch = >95%

2 twitches = 85-90%

3 twitches = 80-85%

4 twitches = 70-75%

When administering reversal drugs, TOFC is used to determine readiness or dosing of medication.

* If using Neostigmine/Glycopyrrolate: generally given when TOFC is 4

* If using Sugammadex: 4 mg/kg for 1-2 twitches, 2 mg/kg for 3-4 twitches, 16 mg/kg for immediate reversal

''Post Tetanic Count (PTC)''

With PTC, a large 50 Hz stimulus is applied for 5 seconds followed by subsequent 1 Hz stimuli over 20 seconds. PTC is used when the TOFC is zero. PTC can indicate time to recovery (e.g. a PTC of 1 indicates recovery from paralysis in approximately 30 minutes).
'''Sites of Use (for helpful graphics, can refer to [https://www.uptodate.com/contents/monitoring-neuromuscular-blockade/print UpToDate]'''<ref>{{Cite web|title=UpToDate|url=https://www.uptodate.com/contents/monitoring-neuromuscular-blockade/print|access-date=2022-07-03|website=www.uptodate.com}}</ref>)

'''Sites of Use (for helpful graphics, can refer to [https://www.uptodate.com/contents/monitoring-neuromuscular-blockade/print UpToDate]'''<ref>{{Cite web|title=UpToDate|url=https://www.uptodate.com/contents/monitoring-neuromuscular-blockade/print|access-date=2022-07-03|website=www.uptodate.com}}</ref>)

''Ulnar Nerve''

Generally the preferred site of monitoring. It is easily accessible. There is a lower chance of direct muscle stimulation which is not an assessment of nerve function/neuromuscular blockade. If surgical positioning interferes with intraoperative monitoring, can consider measuring closer to the end of the case if able to access the limb at that time.
''Facial Nerve''
''Facial Nerve''

''Facial Nerve''

May be necessary depending on surgical positioning, however is prone to more inaccuracies due to direct muscle stimulation. The palpated muscles may either be the orbicularis occuli (which generally correlates with diaphragm and larynx recovery) as well as the geniohyoid muscle (upper airway recovery).
''Posterior Tibial Nerve''
''Posterior Tibial Nerve''

''Posterior Tibial Nerve''

Generally used with AMG.
'''Fade'''

'''Fade'''

Fade is the progressive decrease in amplitude in response to nerve stimulation as a result of increased levels of paralysis. This is important as twitches are counted until the provider appreciates a significant drop in amplitude. It is difficult to assess twitches/fade when the TOFR is >0.4 (which is still a significant paralysis).

Of note, fade is generally not observed when depolarizing agents such as succinylcholine are used (instead, there is a uniform decrease in amplitude). Fade may still be observed with depolarizing agents if patients are in phase II of paralysis where there is desensitization of the neuromuscular junction after prolonged acetylcholine channel opening.

==Reversal Methods (with dosing)==

===Traditional Agents===
'''Glycopyrrolate''' (given first to prevent bradycardia): 0.1-0.2 mg/kg IV

'''Neostigmine:''' 0.03-0.07 mg/kg IV (max 5 mg)

=== <big>Newer Agents</big> ===
'''Sugammadex:''' 4 mg/kg for 1-2 twitches, 2 mg/kg for 3-4 twitches, 16 mg/kg for immediate reversal

Considerations for Sugammadex include the risk of arrhythmias, hypersensitivity reactions (increased with larger doses). Although there is concern with the use of Sugammadex in patients with kidney dysfunction (as it is renally cleared), recent studies have shown its safe use in patients with end stage renal disease (ESRD)<ref>{{Cite journal|last=Paredes|first=Stephania|last2=Porter|first2=Steven B.|last3=Porter|first3=Ivan E.|last4=Renew|first4=J. Ross|date=2020-12|title=Sugammadex use in patients with end-stage renal disease: a historical cohort study|url=https://pubmed.ncbi.nlm.nih.gov/32949009/|journal=Canadian Journal of Anaesthesia = Journal Canadien D'anesthesie|volume=67|issue=12|pages=1789–1797|doi=10.1007/s12630-020-01812-3|issn=1496-8975|pmid=32949009}}</ref>.

==References==

[[Category:Drug reference]]

Neuromuscular blockade

2022-07-04T11:41:29Z

Bsumida1: Formatting