Im posted as duty doctor in cath lab cardiac hospital…. Its new for me ….. so how to handle cases and give prescription

Reading File

Finding Sources

Searching the Web

cath lab duty doctor responsibilities cardiac catheterization lab protocols prescriptions

Finding Sources

Reading File

Finding Sources

I now have enough information to give a thorough, practical answer. Let me compile it.

Cath Lab Duty Doctor - Practical Guide

Welcome to the cath lab! Here is a structured, practical breakdown of your role and what you need to know.

1. Your Core Role as Duty Doctor

As duty doctor in the cath lab, your responsibilities span three phases:

Pre-procedure

Review the patient's history, ECG, recent labs (CBC, renal function, coagulation, HbA1c for diabetics), and old angiography reports
Confirm informed consent is obtained
Check allergies - especially to contrast dye and iodine
Confirm pre-procedure medications are given
Ensure IV access, pre-hydration if needed (especially for renal impairment patients)
Hold metformin 24-48 hours before contrast procedures (risk of lactic acidosis)
Check if the patient is on anticoagulants (warfarin, NOACs) - may need to be bridged or held

Peri-procedure

Monitor vitals, ECG, SpO2 continuously
Anticipate and manage acute complications (see below)
Assist with medications during the procedure

Post-procedure

Ensure access site hemostasis (radial or femoral)
Write post-procedure orders
Monitor for complications

2. Common Cases You Will Handle

A. Elective Coronary Angiography (Diagnostic)

Patient comes for evaluation of suspected CAD.

Pre-procedure orders:

NPO 4-6 hours (solids), allow small sips of water up to 2 hours
Tab. Aspirin 300 mg loading (if not on it already)
Tab. Clopidogrel 300 mg loading (if PCI anticipated)
Inj. Heparin will be given in the lab (typically 70-100 units/kg IV)
Inj. Ondansetron 4 mg IV PRN nausea
IV fluids: NS 100 ml/hr for renal protection pre-contrast

Post-procedure orders (radial access):

TR Band / radial compression device for 2 hours, gradually deflate
Tab. Aspirin 75-150 mg OD (continue)
Tab. Clopidogrel 75 mg OD (if stent placed - dual antiplatelet for 12 months for ACS, 1-6 months for stable angina)
Tab. Pantoprazole 40 mg BD (gastroprotection with dual antiplatelet)
IV fluids NS 500-1000 ml post-procedure for contrast nephropathy prevention
Check urine output, monitor renal function at 24-48 hours
Restart metformin after 48 hours only if creatinine is normal

B. STEMI (Primary PCI - Most Urgent Case)

Target: Door-to-balloon time < 90 minutes

The Washington Manual is clear: "Primary PCI is the preferred reperfusion strategy when available within 90 minutes of first medical contact."

Immediate medications (give ASAP before cath lab):

Tab. Aspirin 300 mg loading (chewable/crushed) - STAT
Tab. Ticagrelor 180 mg loading (preferred) OR Tab. Prasugrel 60 mg OR Tab. Clopidogrel 300-600 mg
Inj. Heparin 70-100 units/kg IV bolus (or Bivalirudin as alternative)
Tab. Atorvastatin 80 mg (high-intensity statin)
Inj. Nitroglycerin IV 5-10 mcg/min (avoid if SBP <90 mmHg, RV infarct, HR >100 or <50, or recent sildenafil use)
Inj. Morphine 2-4 mg IV for refractory chest pain
Oral Beta-blocker (Metoprolol 25-50 mg) - start within 24 hours IF no heart failure, no cardiogenic shock, no advanced heart block, SBP >120, HR 60-110

In the lab: Primary PCI + stenting of culprit vessel. If patient is in cardiogenic shock - culprit-only PCI (not multi-vessel, per CULPRIT-SHOCK trial).

Contraindications to fibrinolytics (if PCI unavailable): Prior intracranial hemorrhage, recent stroke <3 months, active bleeding, aortic dissection, severe hypertension >180/110 uncontrolled.

C. NSTEMI / Unstable Angina

Risk stratify with TIMI score (1 point each):

Age >65
Known CAD (stenosis >50%)
2+ episodes of chest pain in 24 hours
ST/T wave changes on ECG
Elevated cardiac biomarkers (troponin/CK-MB)
Aspirin use in the last 7 days
3+ CAD risk factors (family history, DM, HTN, hyperlipidemia, smoking)

TIMI ≥3 = high risk - urgent angiography within 24 hours

High-risk features requiring urgent angiography <2 hours:

Recurrent angina despite therapy
Signs of heart failure / pulmonary edema / shock
New or worsening MR
New LBBB
Sustained VT

Medications:

Tab. Aspirin 300 mg loading, then 75 mg OD
Tab. Ticagrelor 180 mg loading, then 90 mg BD OR Clopidogrel 300 mg then 75 mg OD
Inj. Low-molecular-weight heparin (Enoxaparin) 1 mg/kg SC BD OR Inj. Unfractionated heparin infusion
Tab. Beta-blocker (Metoprolol 25-50 mg BD - if no contraindications)
Tab. Isosorbide mononitrate 10 mg TDS or nitrate patch for ongoing angina
Tab. Atorvastatin 80 mg nocte
Tab. Pantoprazole 40 mg BD

3. Key Medications & Their Role in Cath Lab

Drug	Class	Dose	Use
Aspirin	Antiplatelet	300 mg load, 75 mg OD	All ACS
Ticagrelor	Antiplatelet (P2Y12)	180 mg load, 90 mg BD	ACS (preferred)
Clopidogrel	Antiplatelet (P2Y12)	300-600 mg load, 75 mg OD	ACS / fibrinolysis
UFH (Heparin)	Anticoagulant	70-100 U/kg IV bolus	PCI during procedure
Enoxaparin	LMWH	1 mg/kg SC BD	NSTEMI/AUA medical management
Bivalirudin	DTI	0.75 mg/kg bolus + 1.75 mg/kg/hr	Alternative to heparin in PCI
Atorvastatin	Statin	80 mg nocte	All ACS - start immediately
Metoprolol	Beta-blocker	25-50 mg BD oral	STEMI, tachyarrhythmias (if no contraindications)
Nitroglycerin	Nitrate	IV drip or sublingual	Chest pain, HTN control
Morphine	Opioid	2-4 mg IV	Refractory chest pain

4. Complications to Watch For

Complication	Signs	Action
Contrast allergy / anaphylaxis	Urticaria, bronchospasm, hypotension	Inj. Adrenaline 0.5 mg IM, IV antihistamine, steroids, fluids
Contrast-induced nephropathy	Rise in creatinine 24-48 hrs post	Pre-hydrate, N-acetylcysteine, avoid nephrotoxins, hold metformin
Access site hematoma (femoral)	Expanding groin swelling	Manual pressure, reverse heparin with protamine if needed
Radial artery spasm	Pain, resistance during procedure	Intracoronary / intra-arterial cocktail (verapamil + nitroglycerin + lidocaine)
No-reflow / slow flow	Persistent ST elevation after PCI	Intracoronary adenosine, verapamil, or nitroprusside
Tamponade	Hypotension, JVD, muffled sounds, equalization of pressures	Emergency pericardiocentesis
Arrhythmia (VF/VT)	Sudden hemodynamic collapse	Defibrillation (200J biphasic), CPR protocol
Vasovagal reaction	Bradycardia + hypotension	Atropine 0.6-1 mg IV, IV fluids, Trendelenburg position

5. Emergency Drugs to Know (Keep at Bedside in Cath Lab)

Inj. Atropine 0.6 mg IV (bradycardia, vasovagal)
Inj. Adrenaline/Epinephrine 1 mg IV (cardiac arrest, anaphylaxis)
Inj. Amiodarone 150-300 mg IV slow (VT/VF resistant to shock)
Inj. Dopamine/Noradrenaline infusion (cardiogenic shock)
Inj. Protamine sulfate (reverses UFH if excess bleeding)
Inj. Adenosine (SVT, no-reflow)
Inj. Furosemide 40 mg IV (acute pulmonary edema, fluid overload)

6. Practical Tips for New Cath Lab Doctors

Always check renal function before contrast - if eGFR <30, alert senior, consider pre-hydration or iso-osmolar contrast
Know the TR band protocol - radial access hemostasis takes 2-4 hours; deflate slowly to prevent re-bleeding
ECG interpretation is key - You must recognize STEMI, posterior MI (ST depression V1-V3 = posterior STEMI), RV infarct (ST elevation in V4R)
RV infarct rules: Give IV fluids (RV is preload-dependent), avoid nitrates, diuretics
Keep a short handover note for each patient - time of arrival, procedure done, sheath removed, current status, any issues
Don't hesitate to call your senior/interventional cardiologist - cath lab complications can escalate fast
Contrast pre-medication for allergy history: Methylprednisolone 32 mg oral 12 and 2 hours before + Diphenhydramine 50 mg 1 hour before

This guide covers the vast majority of day-to-day cath lab duty scenarios. As you get more exposure, the rhythm of managing pre-cath workups, monitoring during cases, and handling post-procedure care will become second nature. When in doubt, always escalate early - no senior cardiologist minds being called. - The Washington Manual of Medical Therapeutics

This is a shared conversation. Sign in to Orris to start your own chat.