Effectiveness of Cryotherapy (Cooling Gel Pack) on Procedural Pain and Distress During Chest Tube Removal Post-Coronary Artery Bypass Graft (CABG) Surgery: A Randomized Controlled Trial

Abstract

Background: Chest Tube Removal (CTR) is an essential but highly painful and distressing procedure routinely performed during the immediate post-operative phase in patients undergoing Coronary Artery Bypass Graft (CABG) surgery. While pharmacological analgesia is standard, it often fails to provide complete relief and is associated with systemic side effects. Non-pharmacological interventions, such as cryotherapy, present a viable, low-risk adjuvant approach.

Objectives

1.     To assess and compare the baseline and post-procedural level of pain intensity and distress in the experimental and control groups.

2.     To evaluate the clinical effectiveness of cold application (cooling gel pack) on procedural pain and distress between the groups.

3.     To determine the association between post-test pain levels and selected socio-demographic and clinical variables within the experimental group.

Methods: A true experimental randomized controlled trial (post-test-only design with baseline clinical parameters) was conducted in the post-operative Cardiac Advanced Intensive Care Unit (AICU) of Fortis Hospital, Bangalore. Sixty post-CABG patients were selected using simple random sampling (lottery method) and allocated equally (n = 30 per group) to either the experimental or control group.

The experimental group received a cold application (cooling gel pack wrapped in sterile gauze) around the chest tube insertion site for 15 minutes prior to CTR in addition to the standard hospital routine 

(Intravenous [IV] Paracetamol/Inj. Perfalgan 1 g administered 30 minutes prior to the procedure). The control group received only the standard hospital pharmacological routine.

Pain intensity was assessed using the Visual Analogue Scale (VAS), and pain distress was evaluated using the Modified Comfort Scale (incorporating physiological parameters: Heart Rate [HR], Blood Pressure [BP], Respiratory Rate [RR], and Oxygen Saturation [SpO₂]). Assessments were conducted 30 minutes before CTR (baseline), within 5 minutes of cold application/CTR (Post-test I), and 20 minutes post-procedure (Post-test II).

Results: At Post-test I (within 5 minutes of CTR), 100% (n = 30) of the control group experienced very severe pain distress, whereas in the experimental group, severe pain distress was limited to 65% (n = 19.5 average weighted index) and very severe distress to 40% (n = 12). At Post-test II (20 minutes post-CTR), 85% (n = 25.5) of the experimental group experienced only mild distress compared to 35% (n = 10.5) in the control group.

For pain intensity (VAS), at Post-test I, 100% (n = 30) of the control group reported very severe pain compared to 97.5% (n = 29.25) in the experimental group. By Post-test II, 50% (n = 15) of the experimental group achieved mild pain levels, while 87.5% (n = 26.25) of the control group still suffered from moderate pain.

Independent t-tests demonstrated highly significant differences between the groups. For pain distress, Post-test I showed t = 6.442 (p < 0.05) and Post-test II showed t = 6.731 (p < 0.05). For pain intensity, Post-test I showed t = 4.1018 (p < 0.05) and Post-test II showed t = 4.60 (p < 0.05).

Conclusion: Pre-procedural localized cryotherapy using cooling gel packs significantly mitigates both the subjective intensity of pain and the physiological/behavioral distress associated with chest tube removal in post-CABG patients. Integrating cryotherapy into cardiothoracic ICU protocols represents an effective, safe, and easily implemented nursing intervention.