Interventions.

To ensure standardization, all taping procedures were performed by a certified physiotherapist with more than 10 years of experience, within 6–8 hours after the participant’s transfer to the cardiovascular surgery ward. In addition to the allocated taping intervention, all participants received the institution’s standard postoperative care following CABG. This included routine medical management, respiratory physiotherapy (diaphragmatic breathing exercises, coughing exercises, incentive spirometry, and chest percussion), early mobilization, nursing care, and standard postoperative analgesia. Postoperative care was continued until hospital discharge according to routine institutional practice. To ensure intervention fidelity, all taping procedures were performed by the same certified physiotherapist using predefined anatomical landmarks and a standardized application protocol.

Elastic therapeutic taping group.

Elastic therapeutic tape (Kinesio® Tex Gold, Kinesio Holding Corporation, USA) was applied bilaterally approximately 3 cm lateral to the sternotomy incision in a craniocaudal direction along the anterior thoracic wall. Five-centimeter tapes were applied with 25–35% tension, with the ends placed without tension and the incision avoided. All applications followed a standardized anatomical template to enhance mechanoreceptive and proprioceptive input.

Placebo taping group.

The same tape was applied to the same anatomical regions without tension and without therapeutic principles.

Sham taping group.

Tape was applied without tension to anatomically unrelated regions (scapular or paraspinal areas) to control therapist contact. All sham applications were performed by the same practitioner, using a standardized contact duration and a predefined template. All groups received the same standard postoperative analgesia protocol.

In all three groups, the tape was applied once and remained in place until completion of the 48-hour follow-up period unless early removal was required because of skin irritation or tape detachment. Representative photographs illustrating the ETT, placebo, and sham taping procedures are presented in Fig 2.

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Fig 2. Representative photographs of the taping procedures.

(A–B) Elastic therapeutic taping (ETT). (C–D) Placebo taping (PT). (E–F) Sham taping (ST). Clinical photographs are published with written informed consent from the participants.

https://doi.org/10.1371/journal.pone.0359282.g002

Pain intensity.

Pain intensity was assessed using a 100-mm Visual Analog Scale (VAS), a valid and reliable instrument for measuring acute postoperative pain [10,11]. Scores were recorded at rest and during coughing at each time point. The sensitivity of this scale for dynamically monitoring postoperative pain has been highlighted in recent studies [4].

Oxygen saturation (SpO₂).

Peripheral SpO₂ was measured at each time point using a portable pulse oximeter (H100B, Edan Instruments, Shenzhen, China), with values averaged from three consecutive readings [12]. Pulse oximetry is a valid and reliable method for non-invasive assessment of peripheral oxygen saturation [13]

Sleep quality, fatigue, and anxiety.

VAS-based assessments have demonstrated acceptable validity and reliability for evaluating acute postoperative symptoms, including anxiety and fatigue, and have been used to monitor changes in perceived sleep quality [14–16].

Functional mobility.

Functional mobility was assessed using standardized single-task Timed Up and Go (TUG) test [17]. Participants stood up from a chair, walked 3 meters, turned around, and returned to a seated position, with completion time recorded in seconds. A research assistant accompanied participants throughout the test to ensure safety. TUG test is a valid and reliable measure of functional mobility in cardiovascular populations [17].

Analgesic use and length of hospital stay (LOS): Analgesic use during the first 48 postoperative hours was categorized as intravenous paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs), and weak opioids (tramadol). Intravenous paracetamol (1000 mg) was administered as part of the standard postoperative analgesic protocol; however, total paracetamol consumption could vary according to individual pain levels and clinical requirements. Rescue tramadol (50 mg) was administered when VAS ≥ 40 mm and repeated as needed. Total paracetamol and tramadol doses were calculated cumulatively (mg), and NSAID use was recorded as yes/no. NSAID administration was not protocolized and was left to the discretion of the treating physician according to routine clinical practice. Analgesic data were verified using nursing records and the hospital information system. LOS was defined as the number of days from surgery to hospital discharge, including both ICU and ward stays. Hospital discharge was determined by the cardiovascular surgery team according to routine institutional clinical criteria and was independent of the study investigators.

Safety monitoring.

Skin reactions (redness, irritation, itching) and other adverse events were monitored and documented. No serious adverse events occurred during the study. Two participants in the ETT group experienced mild skin redness, and one participant in the placebo group reported mild itching. No adverse events were observed in the sham group. None of these events required medical treatment, resulted in premature tape removal, or led to study withdrawal. No patients required ICU readmission or reoperation during the study period, and no major postoperative complications were observed.

Pain control and underlying mechanisms.

The analgesic effect of ETT may be explained by both neurophysiological and biomechanical mechanisms [19]. Continuous cutaneous stimulation may enhance mechanoreceptor activation and inhibit nociceptive input [20]. In the present study, the approximately 20–22 mm reduction in VAS scores observed in the ETT group exceeded the reported minimal clinically important difference of 9.9 mm for acute postoperative pain measured on a 100-mm visual analog scale, indicating a clinically meaningful effect [21].

The significant reduction in movement-evoked pain during coughing suggests that ETT may exert effects beyond sensory modulation. After median sternotomy, the soft tissue undergoes micro-movements continuously stimulating nociceptors [1,6]. ETT uses gentle elevation of the skin and low level of tension applied to alter the mechanical properties of the underlying tissue, thus enhancing proprioception and musculofascial stability [22]. It has been proposed that ETT limits micro-movements and reduces mechanically induced nociceptor activation [23]. ETT enhances proprioceptive input, improving neuromuscular control and suppressing functional pain [24]. Although these neurophysiological and biomechanical mechanisms are biologically plausible and supported by previous studies, they were not directly evaluated in the present study. Therefore, they should be considered as potential explanations for the observed clinical outcomes rather than confirmed mechanisms of action.

The lack of significant differences between the placebo and sham groups suggests that the analgesic effects of ETT were not attributable to expectancy alone [25]. This is consistent with previous studies of patients who have undergone sternotomy [4,6]. In contrast, the inconsistent results of other trials may have been attributable to inadequate taping techniques or suboptimal tape placement that limited tape recoil in the surgical setting [26]. Our findings suggest that biomechanical support provided under appropriate tension may contribute to the observed analgesic effect.

Due to the numerous factors contributing to anxiety post-CABG surgery, it is not surprising that only doing a local intervention is not enough to change this systemic stress response. Even if expectations and psychological coping may alter how someone perceives pain (for example, that idea that someone expects to be able to identify a trigger), the fact that there is no difference in anxiety among the groups indicates that the analgesic effect of ETT is more due to neurophysiological and biomechanical mechanisms [6,27]. However, previous work has shown that, despite reductions in physical pain, improvements in quality of life and psychological outcomes after sternotomy may be slower or more limited, indicating that psychological and trust-related processes should still be considered alongside pain recovery [28]. Pain reduction became evident at 12 hours and progressed up to 48 hours, suggesting a cumulative time-dependent effect. This finding is consistent with biomechanical models proposing that ETT redistributes mechanical stress around the surgical site [1,22,23].

Effective early pain control may limit central sensitization and reduce the risk of chronic postoperative pain, although the transition from acute to chronic pain is multifactorial and influenced by several patient- and surgery-related factors [29,30]. While Parreira et al. argued that ETT is not more effective than placebo, the absence of analgesic effects in the sham and tension-free placebo groups in our study contradicts this view and supports a role for mechanoreceptive stimulation and biomechanical support [25]. ETT after sternotomy has also been associated with improved respiratory comfort [6]. Our findings suggest that ETT may preferentially reduce functional pain components triggered by movement rather than pain at rest.

The marked reduction in total analgesic and tramadol consumption in the ETT group suggests that the intervention may not only improve subjective pain perception but also reduce postoperative analgesic requirements [6]. However, in that study, analgesic consumption reached a plateau in the early postoperative period, whereas our findings demonstrate a continued reduction in analgesic requirements up to 48 hours. This progressive effect more strongly supports the role of ETT as an opioid-sparing adjuvant during early recovery.

In clinical conditions with lower mechanical stress, such as musculoskeletal pain, the analgesic effects of taping are often limited or inconsistent. In contrast, the marked mechanical instability and inflammatory load of the chest wall after sternotomy increase the need for external support, which may explain the more pronounced clinical benefit observed in this population [25]. Especially in older individuals undergoing CABG with multiple comorbidities, reduced tramadol requirements represent a clinically meaningful benefit by lowering the risk of opioid-related complications, including delirium, respiratory depression, and gastrointestinal side effects.

Similar NSAID use across groups suggests that ETT preferentially reduces severe, movement-evoked pain requiring opioids rather than baseline inflammatory pain. Although benefits have been reported in musculoskeletal conditions, our findings indicate that this effect is most evident in reduced rescue opioid use [31,32]. Comparable reductions in postoperative pain have also been observed after abdominal surgery [33].

In contrast, in surgical populations with different biomechanical demands, such as total knee arthroplasty, ETT has not shown a clear advantage in reducing analgesic use [34]. This may reflect the mechanically sensitive nature of post-sternotomy pain, which is continuously stressed by breathing and thoracic expansion. These findings align with previous sternotomy studies, while inconsistencies reported in other surgical populations and meta-analyses likely reflect differences in biomechanical demands and taping techniques [6,25,35]. Thus, the observed effect cannot be explained by expectancy alone.

Functional improvements and proprioceptive input.

The rapid mobilization and improved TUG performance after ETT suggest that its effects extend beyond nociceptive modulation. This is consistent with evidence showing strong associations between kinesiophobia, pain, disability, and reduced quality of life [36].

Our findings align with this perspective; although kinesiophobia was not directly measured. Objective functional measures such as the TUG capture not only muscular performance but also movement-related fear and self-confidence and are therefore key indicators in postoperative rehabilitation [37]. This is consistent with rehabilitation models showing that physical support enhancing postoperative trunk stability can facilitate mobility [38]. However, subjective confidence does not always correlate with objective walking speed, suggesting that functional improvements may reflect not only perceptual factors but also mechanical and proprioceptive inputs [39]. These correlations should be considered exploratory and hypothesis-generating and require confirmation in future studies.

Respiratory patterns and sleep quality: Secondary effect.

Reduced pain with ETT may lessen guarded breathing and promote more effective ventilation, providing a physiological basis for the observed changes in oxygen saturation. After abdominal surgery, Manzano et al. reported only transient SpO₂ improvements without sustained between-group differences, whereas structural and ventilatory differences after sternotomy may explain the relatively greater changes observed in our study [40]. In addition, routine postoperative oxygen therapy may create a ceiling effect, limiting the detection of true between-group differences in SpO₂ [41].

Postoperative pain is negatively associated with sleep quality, with higher pain strongly disrupting sleep [42]. Consistent with this relationship, reduced pain and improved sleep quality were observed in our study. ETT may indirectly improve sleep by reducing postoperative pain, which is closely associated with postoperative sleep quality [43,44]. Further studies are needed to determine whether this effect is direct or secondary to pain reduction.

Clinical implications and safety.

The approximately 1-day reduction in LOS observed in the ETT group suggests potential benefits for clinical recovery and healthcare resource utilization. Because LOS is influenced by multiple factors, including postoperative complications, hemodynamic stability, discharge practices, and functional recovery, this finding should be interpreted with caution. Similar LOS reductions have been demonstrated with early mobilization protocols across surgical populations [45]. Although patients in the ETT group experienced shorter hospital stays, the present study was not designed to determine the independent contribution of ETT to discharge timing. Larger studies with adjustment for relevant clinical covariates are needed to confirm this association.

ETT is a noninvasive intervention with no serious adverse events, supporting its safety as part of multimodal analgesia and rehabilitation [46]. Together, these findings suggest that ETT may provide symptomatic and operational benefits during early postoperative recovery after sternotomy. Larger multicenter studies are needed to confirm these effects.