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7 Reasons for the Use Vasopressors through Peripheral Catheters

16/12/2019

Teaching in medical school and opinions in literature are in agreement: The application of vasopressors requires central venous access. The reason for this are concerns that vasopressors given over a peripheral venous catheter (PCV) may cause phlebitis or even worse necrosis or ischemia through extravasation.

While irritation of a peripheral vein is often observed with the administration of drugs like potassium or amiodarone, this usually is not the case with the application of, e.g. norepinephrine. Besides, it is essential to keep in mind that the insertion of a central venous catheter (CVC) is technically demanding and takes a certain amount of time when performed correctly. The procedure is also associated with potentially dangerous complications that might be hazardous to the patient.

Therefore a fundamental question arises:

Do all patients that require vasopressors need a central venous catheter?

What about the peripheral access (PVC) - Any dangers there?

Study #1

In 2015 Cardenas-Garcia et al. have published a

open-label, single-centre trial

in which they treated

a total of 734 patients with the vasopressors noradrenaline (506), dobutamine (101 and phenylephrine 176 via peripheral access only.

The average duration of infusion was 49 hours.

They found

extravasation in only 2% of all patients without any further tissue injury following treatment with local phentolamine injection and nitroglycerin paste.

These findings indicate that:

Correctly applied vasopressors via a peripheral line are safe, even if given over several hours
Complications like extravasation are generally rare and are unlikely to cause any further harm

J Hosp Med. 2015 Sep;10(9):581-5. doi: 10.1002/jhm.2394. Epub 2015 May 26.

Study #2

In 2015 Loubani et al. performed a systematic review of extravasation and local tissue injury from the administration of vasopressors through peripheral intravenous catheters and central venous catheters. They looked at

Local tissue injury close to the infusion site
Extravasation of a vasopressor into surrounding tissue or a body cavity
Major disability of the patient

An excellent summary of this study can be found on REBELEM, who correctly states that this review was only for complications from administration of vasopressor, and not a review of the frequency of complications (i.e. instances where no complications occurred).

This review shows nicely though that

Most complications concerned peripheral IV-lines distal to the antecubital or popliteal fossae, and
Almost all occurred in infusions running for more than 4 hours

J Crit Care. 2015 Jun;30(3):653.e9-17. doi: 10.1016/j.jcrc.2015.01.014. Epub 2015 Jan 22

Study #3

In 2017 Lewis at al. performed a retrospective chart review of 202 patients who received vasopressors through a PVL. The primary vasopressors used were norepinephrine and phenylephrine. The most common PVL sites used were the forearm and antecubital fossa. The incidence of extravasation was 4%. All of the events were managed conservatively; none required an antidote or surgical management. Although with many limitations to this review, there is further evidence indicating:

Extravasation seems to be a rather rare complication and again did not result in any further harm for the patient

J Intensive Care Med. 2017 Jan 1:885066616686035.

Study #4

In 2018 Medlej et al. tried to determine the incidence of complications of running vasopressors through PIVs in patients with circulatory shock in a prospective, observational trial. Again, REBELEM has nicely summarized this rather small trial. It is another small indicator that:

In patients with shock, the use of peripheral vasopressors (noradrenaline and dopamine) in a large bore PVC at a proximal site for less than 4 hours is safe!

J Emerg Med. 2018 Jan;54(1):47-53.

Well, how do PVC's compare to CVC's then?

Study #5

In 2018 Ricard JD et al. performed a

Multicenter, controlled, parallel-group, open-label randomized trial

in which

Patients were randomized to receive central venous catheters (135 patients) or peripheral venous catheters (128 patients) as initial venous access.

The primary endpoint was the rate of major catheter-related complications within 28 days.

They found significantly more PVC-related complications per patient when only treated with peripheral lines compared to patients that received at least one CVC.

And they concluded: "central venous catheters should preferably be inserted: a strategy associated with less major complications"

REALLY? Hold on! - let's have a close look at those 'major complications, the PRIMARY endpoint of this study!

Although going through this article several times, it remains difficult to understand how PVC insertion difficulties are comparable major complications.
First of all, difficult venous access is one of the indications for the insertion of a CVC, not its complication. Patients were randomly allocated in a one-to-one ratio to receive a CVC or a PVC. So how can difficult peripheral access be a complication when going for central access directly?

Also, there is considerable doubt whether the occurrence of a pneumothorax can be used to compare complications of these two procedures!

However, when eliminating difficult peripheral access as an indication, there is not much left to say PVCs are associated with more complications than CVCs. Moreover, most clinicians will agree that catheter infections in PVCs are less problematic than when occurring in CVCs.

Given these considerations, it seems safe to say:

In critically ill patients peripheral access can be tricky indeed
PVCs might be associated with more frequent local erythema and extravasation of fluids
Good to know: peripheral access is not associated with more pneumothoraces ; )

Crit Care Med. 2013 Sep;41(9):2108-15

2019 - More Evidence Keeps Rolling In!

Study #6

Tian et al. have performed a

Systematic review

in order to assess

the frequency of complications associated with the delivery of vasopressors via PVCs.

They included

Studies of continuous infusions of vasopressor medications (noradrenaline, adrenaline, metaraminol, phenylephrine, dopamine and vasopressin) delivered via a PiVCs that included at least 20 patients. This resulted in seven observational studies (only) with a total of 1384 patients.

They found that

Extravasation occurred in 3.4% (95% CI 2.5-4.7%) of patients. There were no reported episodes of tissue necrosis or limb ischaemia. All extravasation events were successfully managed conservatively or with vasodilatory medications.

Extravasation seems to be an issue with PVCs, but there is no further information on the size or location of the peripheral line.
Again, no serious side effects were reported, indicating that peripherally administered vasopressors are safe over all when given for a limited duration.

Emerg Med Australas. 2019 Nov 7.

Study #7

Pancaro et al. published

a retrospective cohort study

in which identified

14'385 surgical patients who received peripheral norepinephrine infusions perioperatively with a concentration of 20 µg/mL (a rather low concentration)

They found

Extravasation of norepinephrine in only 5 patients and there where zero related complications requiring surgical or medical intervention. The median time of norepinephrine infusion among these patients was 20 minutes.

This is a fairly good indicator that:

Giving vasopressors through PVC for a limited duration is safe

Extravasation might actually be harmless when applied in rather lower contentrations

Anesthesia & Analgesia. SEPTEMBER 27, 2019

Giving the current evidence available, it seems appropriate to conclude:

The need for vasopressors itself is not a mandatory indication for central venous access

Vasopressors can be safely given through a peripheral venous catheter
- This is especially true when used for a limited time (e.g. less than 4 hours) and when applied in rather lower concentrations.

In the critically ill central venous access will inevitably still be required (advantage of multiple lumens, difficult peripheral access, other drugs that do entitle the use of a CVC etc.)

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Novel Approach to SVT's: Single Syringe Adenosine!

4/12/2019

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Supraventricular tachycardias (SVT) typically refer to tachydysrhythmia arising from above the level of the bundle of His and usually present as a small complex tachycardia. A classification based upon a narrow QRS-complex is useless though as this is also dependent on any pre-existing bundle branch block.

SVT's can be classified a follows

Regular Atrial
Sinus tachycardia
Atrial tachycardia
Atrial flutter
Inappropriate sinus tachycardia
SNRT

Irregular Atrial
Atrial fibrillation
Atrial flutter with variable block
Multifocal atrial tachycardia (MAT)

Regular Atrioventricular
AVRT
AVNRT
Automatic junctional tachycardia

AV nodal re-entry tachycardia (AVNRT) is the most common cause of palpitations in patients with structurally normal hearts and mostly occurs spontaneously or triggered (e.g. exercise, caffeine etc.)

Although usually well tolerated, SVT's can become a potentially life-threatening condition.

Treatment with Adenosine

The American Heart Association 2015 guidelines for Adult Advanced Cardiac Life Support recommends adenosine in non-hypotensive patients with regular narrow complex SVT. Adenosine is an endogenous purine nucleoside that blocks atrioventricular nodal conduction via the A1 receptors in the cardiac tissue. That is why the use of adenosine causes transient asystole, which in turn very often produces a sense of 'impending doom' or a feel that one is about to die.

With a half-life less than 10 seconds, cardioversion can be performed quickly, and side effects usually are limited and short-lasting.

Due to these kinetics, 6 mg of adenosine are classically administered as a rapid intravenous bolus followed by a 20ml saline flush. If the first dose fails to restore normal sinus rhythm, another 12 mg of adenosine are recommended. This can be repeated one more time if necessary. As adenosine and normal saline are mostly applied over a 2-way stop-cock, this procedure might result in a suboptimal application for technical reasons.

Did you know: If adenosine is given over a central line, its dose should be halved!

The Single Syringe Adenosine-Trial

Wouldn't it be great, to simply mix your adenosine into the syringe with the saline flush and administer the 'cocktail' as one? Well, this is exactly what Marc McDowell at al. did.

They performed

a small prospective study

of

53 hemodynamically stable adults who presented to a single emergency department with SVT

patients were given

6 mg of adenosine one of two ways: in a single syringe combined with 18 mL of saline (26 patients) or in two separate syringes, one containing adenosine and the other 20 mL of saline (27 patients)

They found:

More patients in the single-syringe group than the two-syringe group converted to sinus rhythm after the first dose (73.1% vs. 40.7%)

By the way: This is not the first study looking into mixinf adenosine with normal saline. Choi et al. have already mixed 6mg of adenosine with 15ml of normal saline and found a comparable conversion rate compared to the 'conventional' method.

Although both studies show several limitations, there are some important information we can get:

- Concern that diluting adenosine into normal saline maight impair the drug's efficacy is not justified

- Administering adenosine and normal saline in one syringe is safe and at least equaly effective

- This 'Single Syringe'-technique ist technically safer and should be considered in this setting

I personally will will be going down this path from now on.

McDowell M, Mokszycki R, Greenberg A, et al. Single Syringe Administration of Diluted Adenosine. Acad Emerg Med. 2019 Oct 30.

Choi SC, Yoon SK, Kim GW, et al. A convenient method of adenosine administration for paroxysmal supraventricular tachycardia. J Korean Soc Emerg Med 2003;14(3):224-7.

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Reviews and Summaries

7 Reasons for the Use Vasopressors through Peripheral Catheters

What about the peripheral access (PVC) - Any dangers there?

Study #1

Study #2

Study #3

Study #4

Well, how do PVC's compare to CVC's then?

Study #5

2019 - More Evidence Keeps Rolling In!

Study #6

Study #7

Novel Approach to SVT's: Single Syringe Adenosine!

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Reviews and Summaries

7 Reasons for the Use Vasopressors through Peripheral Catheters

What about the peripheral access (PVC) - Any dangers there?

​Study #1

​Study #2

​Study #3

​Study #4

​Well, how do PVC's compare to CVC's then?

​Study #5

​2019 - More Evidence Keeps Rolling In!​

Study #6

​Study #7

Novel Approach to SVT's: Single Syringe Adenosine!

Search

​Translate

Categories

Archives

Author

ABOUT US

SEARCH US

CONTACT US

FOLLOW US

TRUST US

TWEET US

Study #1

Study #2

Study #3

Study #4

Well, how do PVC's compare to CVC's then?

Study #5

2019 - More Evidence Keeps Rolling In!

Study #7

Translate