Arterial Pulse Pressure Variation

Pulse pressure variation (PPV), which quantifies the changes in arterial pulse pressure during mechanical ventilation, is one of the dynamic variables that can predict fluid responsiveness. The underlying hypothesis is that large respiratory changes in left ventricular stroke volume, and thus pulse pressure, occur in cases of biventricular preload responsiveness.1

One of the most important concepts in resuscitation is volume responsiveness, or the ability of the cardiac output to increase in response to a fluid challenge.2


To measure the PPV in a given patient, that patient must have consistent and demonstrable cardiopulmonary interactions. This means that the patient must:

  1. Be in normal sinus rhythm
  2. Be intubated and be mechanically ventilated, making no spontaneous respiratory efforts
  3. Be ventilated with at least 8mL/kg of tidal volume
  4. Have no significant alternations to chest wall compliance, such as an open chest2
From ACEP

Resources:

Regional Anesthesia for Cardiac Surgery

Gathering data for Cardiac ERAS program for our hospital as well as the SCA. This page will be continuously updated as I find more information.

Resources:



What I’m using these days:

  • August 2020: None as we do not have programmable intermittent bolus pumps for regional.

Gabapentinoids

With an opioid crisis at its peak, physicians need to be more cognizant of the various pain modalities available to patients. Gabapentinoids are one of the many non-opioid options to help with acute and chronic pain.

What are gabapentinoids?

Wikipedia

Analgesic mechanisms of gabapentinoids and effects in experimental pain models: a narrative review. British Journal of Anaesthesia. Volume 120, Issue 6, June 2018, Pages 1315-1334.

AAFP.org

FDA

ACPHospitalist.org

Resources:

Non-opioid IV adjuvants in the perioperative period: pharmacological and clinical aspects of ketamine and gabapentinoids. Pharmacol Res. 2012 Apr;65(4):411-29.

Systemic analgesia and co-analgesia. Acta Anaesthesiol Belg. 2006;57(2):113-20.

A comparison of gabapentin and ketamine in acute and chronic pain after hysterectomy. Anesth Analg. 2009 Nov;109(5):1645-50.

Perioperative gabapentin reduces 24 h opioid consumption and improves in-hospital rehabilitation but not post-discharge outcomes after total knee arthroplasty with peripheral nerve block. Br J Anaesth. 2014 Nov;113(5):855-64.

From BJA Anaesth 2914 Nov. Fig 2.

Post‐operative analgesic effects of paracetamol, NSAIDs , glucocorticoids, gabapentinoids and their combinations: a topical review. Acta Anaesthesiol Scand. 2014 Nov;58(10):1165-81.

What our patients are getting:

  • July 2020
    • Cardiac pre-op: Lyrica 150mg PO

Transversus Abdominis Plane (TAP) block

Indications and Technique

Figure 1. Biomed Res Int. 2017; 2017: 8284363.
Figure 1. Anesthesiol Res Pract. 2012; 2012: 731645.
Figure 5. Anesthesiol Res Pract. 2012; 2012: 731645.
Figure 6. Biomed Res Int. 2017; 2017: 8284363.

Pros & Cons

The Effect of Transversus Abdominis Plane Blocks on Postoperative Pain in Laparoscopic Colorectal Surgery: A Prospective, Randomized, Double-Blind Trial. Diseases of the Colon & Rectum: November 2014 – Volume 57 – Issue 11 – p 1290-1297


How to perform a TAP block?

YouTube: U/S guided TAP block

YouTube: RAUKvideos U/S guided TAP block Fast forward to 0:39

YouTube: 3D How-To U/S Guided TAP block Fast forward to 1:00

YouTube: 2012 ISURA TAP block lecture Fast forward to 16:55 for summary.

YouTube: ASRA Society Fast forward to 0:55. Sound off.

YouTube: Pajunk TAP block


Current mix:

  • July 2020
    • 0.25% bupi + epi + 1 mcg/kg dexmedetomidine (roughly 30 ml per side)

Cardiac myxoma

Myxoma is the most common primary benign cardiac tumor, which could lead to some fatal complications because of its strategic position. Although any age can be affected, it predominates in the age group of 30-60 years of age with more than 75% of the affected being women. The occurrence of myxomas in left and right atrium are 75% and 20% respectively.The majority of myxomas present with systemic emboli, fever and/or weight loss, or intracardiac obstruction to blood flow.1 A ‘tumor plop’ is a sound that typically occurs during early diastole and is believed to be caused by motion of the tumor striking the wall of the endocardium. The treatment is surgical excision and key aims of anesthesia care include constant monitoring of systemic blood pressure, adequate IV fluids, and judicious use of vasoactive medications to prevent a fall in systemic vascular resistance.3

Preop

  • A-line/CVP
  • Assess patient symptomatology: SOB, chest pain, changes in pulse pressure/CVP with positioning, heart sounds
  • Adequate PIV access
  • Vasopressors to help with SVR and heart rate control – mass can act as stenotic valve

Intraop

  • Induction: maintain SVR and consider slowing heart rate if mass blocking valves

Postop

2D TEE: X-plane
2D TEE: color flow through mitral valve
2D TEE: LA myxoma
2D TEE: LA myxoma w color
3D TEE: LA myxoma
From OpenAnaesthesia
2D TEE: measurement of stalk
Resected myxoma

References:

Surgical approach

Cardiac myxomas: 24 years of experience in 49 patients. European Journal of Cardio-thoracic Surgery 22 (2002) 971–977.

Anesthesia management

Hemodynamic management of a patient with a huge right atrium myxoma during thoracic vertebral surgery: A case report. Medicine (Baltimore). 2018 Sep; 97(39): e12543.

Anesthetic Management of a Patient With a Giant Right Atrial Myxoma. Semin Cardiothorac Vasc Anesth. 2016 Mar;20(1):104-9.

Anesthetic management of a patient with asymptomatic atrial myxoma for hernia repair. Anaesth Pain & Intensive Care 2016;20(2):246-248

Giant Left Atrial Myxoma Obstructing Mitral Valve Bloodflow. Anesthesiology 7 2019, Vol.131, 151-152.

Anesthetic Management of a Voluminous Left Atrial Myxoma Resection in a 19 Weeks Pregnant with Atypical Clinical Presentation. Case Reports in Anesthesiology, Volume 2019, Article ID 4181502, 6 pages.

Large myxoma causing cardiac arrest during surgery. A Clinical Reports volume 1, Article number: 24 (2015).

Atrial myxomas causing severe left and right ventricular dysfunction. Annals of Cardiac Anaesthesia. Case Report: Year : 2017  |  Volume : 20  |  Issue : 4  |  Page : 450-452.

Intraoperative Diagnosis of Left Atrial Myxoma. Anesthesia & Analgesia: January 1995 – Volume 80 – Issue 1 – p 183-184

Anesthetic experiences of myxoma removal surgery in two patients with Carney complex -A report of two cases-. Korean J Anesthesiol. 2011 Dec; 61(6): 528–532.

Echocardiography

Virtual TEE: Cardiac Myxoma

Intraoperative transesophageal echocardiography assessment of right atrial myxoma resulting in a change of the surgical plan. Ann Card Anaesth 2014;17:306-8.

Dealing with difficult colleagues

We’ve all been there. It starts early and young…. bullies. And then there’s arrogance and difficult attitudes and just overall uncompromising a$$holes. Life throws the full gambit of challenging personalities at us. After awhile, I learned that these people are everywhere. No matter where you go, you can never hide from them.

But what do you do when you come across a confronting/difficult/antagonistic/arrogant/etc colleague at work?


Image from Shuttershock.com

Business Insider, June 2011: 9 Useful Strategies to Dealing with Difficult People at Work

  1. Be calm.
  2. Understand the person’s intentions.
  3. Get some perspective from others.
  4. Let the person know where you are coming from.
  5. Build a rapport.
  6. Treat the person with respect.
  7. Focus on what can be actioned upon.
  8. Ignore.
  9. Escalate to a higher authority for resolution.

Continue reading “Dealing with difficult colleagues”

TransCarotid Artery Revascularization (TCAR)

Surgery and anesthesia for TCAR. #anesthesia #TCAR #carotid #local #stroke #CEA

SilkRoad Medical: TCAR Procedure

Technical aspects of transcarotid artery revascularizationusing the ENROUTE transcarotid neuroprotection and stent system. J Vasc Surg 2017;65:916-20.

TCAR PPT Stony Brook

TCAR With Flow Reversal Is Equal To CEA For Treating High Risk Patients With Carotid Stenosis:DWMRI Findings Prove It (From The PROOF Trial)

Long-term comparative effectiveness of carotid stenting versus carotid endarterectomy in a large tertiary care vascular surgery practice. Journal of Vascular Surgery. Volume 68, Issue 4, October 2018, Pages 1039-1046.

THE CASE FOR TCAR UNDER LOCAL ANESTHESIA PPT: Dec 2017.

Challenging Case: The Consequence of Unmanaged Hypotension After TCAR. Endovascular Today. August 2019.

Preop

  • Dual antiplatelet therapy: Aspirin and clopidogrel
  • Statins
  • Beta blocker

Intraop

  • Local/MAC vs General
  • arterial line
  • Target systolic blood pressure is 140 – 160 mmHg. Consider glycopyrrolate adn vasopressors for hemodynamics.
  • Surgical access: common carotid artery and femoral vein
  • Goal ACT: 250-300

Postop

  • Neuro checks – quick emergence from anesthesia prior to leaving OR
  • ICU postop
  • Tight BP control

Methadone: perioperative pain use

Methadone for perioperative pain #methadone #pain #ERAS

There’s a lot of great data that methadone use decreases postoperative narcotics use in cardiac surgery patients, and I believe it would really be a beneficial drug in an ERAS pathway for early extubation, decreased LOS in ICU and hospital, and better patient satisfaction.  Please see the articles below/attached for references.

Methadone for cardiac surgery: 0.2-0.3 mg/kg prior to incision – perhaps different metabolism on CPB so consider split dosing pre-pump and post-pump. Dose adjustment with age and other co-morbidities. At induction, one half of the study opioid (either 0.15 mg/kg of methadone or 6 μg/kg of fentanyl) was administered via an infusion pump over 5 min. The remainder of the study opioid (0.15 mg/kg of methadone or 6 μg/kg of fentanyl) was infused over the next 2 h. Either 0.3 mg/kg of methadone (maximum dose of 30 mg) or 12 μg/kg of fentanyl (maximum dose of 1200 μg) was added to 100-ml bags of normal saline (total volume 100 ml).

Methadone for non-cardiac surgery: 0.2mg/kg prior to incision. REVIEW: Intraoperative Methadone in Surgical Patients: A Review of Clinical Investigations. Anesthesiology 9 2019, Vol.131, 678-692.

Methadone for obesity: 0.15 mg/kg IBW+20% at induction. J Pain Res. 2018; 11: 2123–2129. Intraoperative use of methadone improves control of postoperative pain in morbidly obese patients: a randomized controlled study.

Methadone for outpatient surgery: 0.15 mg/kg ideal body weight. Anesth Analg. 2019 Apr; 128(4): 802–810. Intraoperative Methadone in Same-Day Ambulatory Surgery: A Randomized, Double-Blinded, Dose-Finding Pilot Study.

OVERALL: A variety of doses have been used in clinical trials, ranging from 0.1 to 0.3 mg/kg, with the majority of studies using a dose of either 0.2 mg/kg or a fixed dose of 20 mg.

Methadone has a long elimination half-life (1–2 days). It is cleared predominantly by hepatic metabolism, primarily via N-demethylation to 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), which is pharmacologically inactive, and thence secondarily to 2-ethyl-5-methyl-3,3-diphenylpyrroline (EMDP).

Together these investigations established that a) CYP3A has no influence on single-dose intravenous or oral methadone plasma concentrations, b) CYP3A plays a minimal (if any) role clinically in single-dose methadone N-demethylation and clearance, c) methadone is not a clinical CYP3A substrate, and d) clinical guidelines stating that methadone is a CYP3A4 substrate and warning about CYP3A4 drug interactions needed revision. In addition, CYPs 2C9, 2C19, and 2D6 do not appear to contribute materially to clinical methadone N-demethylation and clearance.

In summary, it is now obvious that CYP2B6 a) is a predominant catalyst of methadone metabolism in vitro; b) mediates clinical methadone metabolism, clearance, stereoselective disposition, and drug-drug interactions; and c) genetic polymorphisms influence methadone disposition. Thus, both constitutive variability due to CYP2B6 genetics, and CYP2B6-mediated drug interactions, can alter methadone disposition, clinical effect, and drug safety. Rewritten clinical guidelines stating that methadone is a CYP2B6 substrate and warning about CYP2B6 drug interactions may improve methadone use, treatment of pain and substance abuse, and patient safety.

FDA Drug Datasheet

From Anesthesiology 5 2015, Vol.122, 1112-1122.
From Anesth Analg. 2019 Apr; 128(4): 802–810.

What I’m doing these days:

  • July 2020


Adult Cardiothoracic

Adult Non-Cardiac

Adult Outpatient

Pediatric Surgery

Methadone Pharmacology & Effects

Updated July 2020

Prescription of Controlled Substances: Benefits and Risks. [Updated 2020 Jun 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537318/

The role of methadone in opioid rotation-a Polish experience. Support Care Cancer. 2009 May;17(5):607-12.

Worth Losing Friends Over — Doctor Enough

Today, I hurt. I’ve been talking about this pandemic for well over a month. My friend list is dwindling, and there are several people I don’t plan on catching up with when this pandemic is over—and now entire communities. America’s privilege is showing, in a terrible way. Rural areas that have been luckily unaffected are […]

via Worth Losing Friends Over — Doctor Enough