For the prevention of further Pulmonary Embolism, which of the following is the correct Maintenance Infusion dose of Intravenous Heparin?

Appeared in: AIIMS Bhopal NO - 2018 (Shift-1st)

Explanation

Standard weight-based protocols for Pulmonary Embolism (PE) recommend an initial maintenance infusion rate of 15-22 units/kg/hour.
The dose of 18 units/kg/hour falls directly within this established therapeutic range, making it the correct choice.
This continuous infusion typically follows an initial intravenous bolus dose of 80-100 units/kg to rapidly achieve anticoagulation.
The primary goal is to maintain the activated partial thromboplastin time (aPTT) at a therapeutic level, which is 1.5 to 2.5 times the control value.

Option A: This dose is significantly higher than the standard initial rate of 15-22 u/kg/hr, which substantially increases the risk of bleeding and hemorrhage.
Option B: This is a dangerously excessive dose that falls far outside therapeutic guidelines and would likely lead to severe hemorrhagic complications.
Option C: This dose is well above the recommended starting range for a heparin maintenance infusion, posing an unnecessary and high risk of bleeding complications.

Clinical Relevance

Nursing practice connection: Knowing Intravenous Heparin Dosing for Pulmonary Embolism helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Correct heparin dosing is a critical nursing responsibility, requiring a careful balance between preventing life-threatening emboli and avoiding the significant risk of iatrogenic bleeding.
Nurses must meticulously monitor the aPTT, assess for signs of bleeding (e.g., hematuria, melena, epistaxis), and implement bleeding precautions for all patients on heparin therapy.
The antidote for heparin overdose, protamine sulfate, must be readily available on the unit where heparin infusions are administered.

How to Approach the Question

First, identify the key elements of the question: 'Pulmonary Embolism', 'Maintenance Infusion', and 'Intravenous Heparin dose'.
Recognize this as a factual recall question that tests your knowledge of a standard drug protocol.
Recall that heparin therapy for acute PE is administered using a weight-based protocol, which includes an initial bolus and a continuous maintenance infusion.
Access your knowledge of the standard maintenance infusion rate, which is established to be in the range of 15-22 u/kg/hr.
Compare the given options to this standard therapeutic range. The option of 18 u/kg/hr fits perfectly within this range.
Eliminate the other options (28, 38, 48 u/kg/hr) as they are clearly too high for an initial maintenance dose and would represent a significant risk of overdose and bleeding.

Concept Tested & Keywords

Concept Tested: Intravenous Heparin Dosing for Pulmonary Embolism
Stem keywords: Pulmonary Embolism, Maintenance Infusion, Intravenous Heparin, dose
Lead-in keywords: correct

QS8eRF_neulGx4EnCf87Xd

E6 Pharmacology Katzung 16e p. 958-960

Practise the full AIIMS Bhopal NO - 2018 (Shift-1st)

Attempt every question from this paper in a timed mock, then review the full solution for each one.