Analysis the effectiveness nursing interventions for contrast-induced adverse reactions in postoperative general surgery patients undergoing contrast-enhanced computed tomography scans

Abstract

BACKGROUND

Contrast-enhanced computed tomography (CT) is common postoperatively; however, contrast-induced adverse reactions increase the risk of renal injury and inflammation, requiring effective nursing care.

AIM

To investigate the efficacy of comprehensive precision nursing interventions in preventing and managing contrast-induced adverse reactions during abdominal contrast-enhanced CT among postoperative general surgery patients.

METHODS

Eighty patients undergoing elective surgery in the Department of General Surgery at the Beihua University Affiliated Hospital between January 2021 and January 2025, who required postoperative abdominal contrast-enhanced CT, were enrolled. The patients were randomly assigned to two groups using a random number table: A control group (n = 40) that received conventional nursing care, and an observation group (n = 40) that received comprehensive precision nursing interventions in addition to conventional care. Comparisons were made between the groups for the following: Heart rate variability indices, including SD of normal R-R intervals (SDNN) and root mean square of successive R-R interval differences (RMSSD); inflammatory cytokine levels, including interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α); patient-reported outcomes; and procedure-related complications (e.g., contrast extravasation and acute adverse reactions).

RESULTS

Post-examination, compared with the control group, the observation group exhibited significantly lower increase in serum neutrophil gelatinase-associated lipocalin and cystatin C (P < 0.05), higher SDNN and RMSSD values (P < 0.05), and markedly reduced IL-6 and TNF-α concentrations (P < 0.05). Regarding patient subjective experiences, the observation group demonstrated superior scores for emotional functioning, overall health status, and discomfort when compared with the control group (P < 0.05). Furthermore, incidence of contrast medium extravasation and overall adverse reaction rates were lower in the observation group than those in the control group (P < 0.05).

CONCLUSION

Implementing comprehensive, precision nursing interventions for postoperative general surgery patients helps mitigate early renal tubular damage caused by iodinated contrast agents, maintains autonomic nervous system stability, alleviates systemic inflammatory responses, and enhances patients’ subjective comfort and treatment experience. Concurrently, this nursing model effectively reduces the complication risks associated with contrast agent administration, thereby improving the safety and clinical service quality of contrast-enhanced CT.

Key Words: General surgery postoperative; Contrast-enhanced computed tomography; Contrast-induced adverse reactions; Precision nursing; Subclinical renal injury; Heart rate variability; Patient-reported outcomes

Core Tip: This study explored comprehensive precision nursing for postoperative general surgery patients undergoing contrast-enhanced computed tomography. Nursing care mitigated subclinical renal injury, stabilized the autonomic nervous system, reduced inflammation and contrast-induced adverse reactions, improved patient-reported outcomes, and enhanced scan safety and quality.

INTRODUCTION

Computed tomography (CT) with contrast enhancement is a crucial radiological method for evaluating surgical outcomes and monitoring recovery progress following general surgical procedures[1]. Using iodinated contrast agents to alter the X-ray attenuation coefficient of local tissues enhances the contrast density between normal and pathological tissues, thereby improving CT image resolution and diagnostic value[2]. However, the administration of high-dose contrast agents carries multiple risks, particularly within the first 24 hours after surgery. During this period, the body remains in a state of increased stress, immune imbalance, and hemodynamic instability, with a marked reduction in glomerular filtration rate. Consequently, the probability of developing contrast-induced nephropathy increases significantly[3,4].

Traditional nursing practices have emphasized preoperative education and vital signs monitoring while neglecting comprehensive assessment and intervention for patients’ multifaceted physiological, psychological, and social risks. In contrast, the modern patient-centered precision management model, which encompasses risk screening, health guidance, psychological support, hydration management, dynamic monitoring, and emergency preparedness, has significantly reduced the adverse events associated with postoperative contrast-enhanced CT[5,6]. However, high-quality nursing studies among postoperative general surgery patients remain limited. This study aimed to develop and implement a comprehensive nursing intervention protocol for such patients, enhance the safety of postoperative contrast-enhanced CT, optimize perioperative examination workflows, and provide evidence for establishing specialized nursing standards.

MATERIALS AND METHODS

General data

Eighty patients who underwent elective surgery at the Department of General Surgery, Affiliated Hospital of Beihua University, between January 2021 and January 2025, and required post-operative contrast-enhanced CT, were enrolled. Patients that met the inclusion criteria were randomly assigned using a random number table to either an observation or control group, comprising 40 patients each. The control group comprised 18 males and 22 females aged 35-75 years (mean, 52.35 ± 8.61 years). The observation group included 21 males and 19 females aged 32-78 years (mean, 51.78 ± 9.20 years). No statistically significant differences were observed between the groups in terms of baseline characteristics (P > 0.05).

Inclusion criteria were as follows: (1) Postoperative general surgery patients with clear indications for abdominal contrast-enhanced CT; (2) Preserved renal function estimated glomerular filtration rate (eGFR) ≥ 60 mL/minute/1.73 m²; (3) No history of iodine contrast medium allergy; and (4) Signed informed consent. Exclusion criteria were as follows: (1) Concurrent severe cardiac insufficiency or autoimmune disease; (2) Moderate-to-severe chronic kidney disease (eGFR < 60 mL/minute/1.73 m²); (3) Acute phase of hyperthyroidism; (4) Pregnant or lactating women; and (5) Mental disorders or inability to cooperate with the examination.

Intervention methods

The control group received standard nursing care. Preoperatively, nursing staff provided systematic health education to patients and their families, emphasizing the purpose of the examination, procedural steps, pharmacological effects of the iodinated contrast agent, and prevention and emergency management of acute or delayed adverse reactions. The patients were fully informed, and they signed informed consent forms regarding the use of the contrast agents. During the procedure, strict adherence to operational protocols was maintained, and the isotonic non-ionic contrast agent, iopamidol, was administered at a dose of 1.5 mL/kg body weight. Using a dual-chamber syringe, the contrast agent was injected at a rate of 3.0 mL/second via the antecubital vein, followed by flushing with 20 mL of saline. Vital signs were continuously monitored throughout the injection. Immediately after the procedure, the patients were transferred to an observation area for a minimum of 15-minute. Postoperatively, the nursing staff continuously monitored patients’ appearance, respiratory rate, blood pressure, and oxygen saturation for acute adverse reactions, such as nausea, vomiting, or rash. Following the examination, the patients were instructed to drink an adequate volume of water (≥ 500 mL) to facilitate rapid excretion of the contrast agent, thereby reducing the risk of renal tubular toxicity and systemic adverse reactions.

The observation group received closed-loop precision nursing care. Preoperatively, the patients were categorized into low-, medium-, and high-risk groups using a modified risk assessment scale (three dimensions: Age, allergy history, and history/postoperative duration), with high-risk individuals undergoing double monitoring. Those scoring ≥ 50 on the Self-Rating Anxiety Scale received one-to-one cognitive behavioral intervention alongside viewing a 3-minute contrast agent metabolism animation. During the injection, heart rate and blood pressure were monitored in real time. If heart rate increased by > 20% or systolic blood pressure fluctuated by > 10 mmHg, the injection was immediately halted and the “4-7-8” breathing technique combined with progressive muscle relaxation initiated. Post-procedure observation lasted for 30 minutes, with particular vigilance for delayed rash or laryngeal edema. Personalized hydration protocols mandate 800-1000 mL of lukewarm water within 2 hours, supplemented by 24-hour follow-up serum creatinine level and urinalysis to detect renal injury early.

Observation indicators

Subclinical kidney injury markers: Venous blood samples were collected 24 hours before and after the examination. Serum was obtained after centrifugation and analyzed using enzyme-linked immunosorbent assay and particle-enhanced transmission immunoturbidimetry to measure serum levels of neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C (CysC) levels[7,8].

Autonomic function changes: Dynamic electrocardiography analyzed heart rate variability (HRV) indices before and after the examination (from contrast agent injection initiation to 5 minutes post-injection), including SD of the normal-to-normal R-R intervals (SDNN) and root mean square of successive differences between adjacent root mean square of successive R-R interval differences (RMSSD)[9].

Inflammatory stress response: Assessed by measurement of serum interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels prior to and following the examination.

Patient-reported outcomes: Assessed using the EORTC QLQ-C30 questionnaire 1 hour before and 1 hour after the examination, and by analyzing changes in scores across three sub-dimensions: Emotional functioning, overall health status, and discomfort[10].

Procedure-related complications include contrast medium extravasation and acute adverse reactions: Contrast medium extravasation is classified according to the American Society for Parenteral and Intravenous Nutrition criteria[11]. Acute adverse reactions were graded according to the American Society of Radiology Contrast Media Manual[12]: Mild (e.g., nausea and rash requiring no intervention), moderate (e.g., extensive urticaria or bronchospasm requiring pharmacological intervention), and severe (e.g., hypotension, laryngeal edema, or arrhythmia requiring emergency resuscitation).

Statistical analysis

Data analysis was performed using SPSS software (version 26.0). For continuous variables that meet normal distribution, results are presented as mean ± SD, with intergroup comparisons conducted using independent samples t-tests. Categorical variables are expressed as n (%), and analyzed using the χ² tests or Fisher’s exact probability test. Differences were considered statistically significant at P < 0.05.

RESULTS

Comparison of early renal injury markers between the two patient groups

Prior to the examination, no significant differences were observed between the two groups in terms of NGAL and CysC levels (P > 0.05). Following the examination, both groups exhibited elevated levels, yet the increase in NGAL and CysC levels in the observation group was significantly lower than that in the control group (P < 0.05) (Table 1).

Table 1 Comparison of changes in early renal injury markers between two patient groups (mean ± SD).

Group	Patients	NGAL (ng/mL)		CysC (mg/L)
		Before	After	Before	After
Control	40	47.15 ± 9.21	79.46 ± 16.80	0.88 ± 0.12	1.07 ± 0.16
Observation	40	46.27 ± 8.51	58.32 ± 12.61	0.89 ± 0.14	0.99 ± 0.13
t		0.444	6.365	0.343	2.454
P value		0.658	0.000	0.733	0.016

NGAL: Neutrophil gelatinase-associated lipocalin; CysC: Cystatin C.

Comparison of HRV time-domain parameters between the two patient groups

Prior to the examination, the differences in SDNN and RMSSD between the two patient groups were not statistically significant (P > 0.05). Both SDNN and RMSSD were significantly higher in the observation group than those in the control group (P < 0.05) (Table 2).

Table 2 Comparison of heart rate variability time-domain parameters between the two patient groups (mean ± SD, millisecond).

Group	Patients	SDNN		RMSSD
		Before	After	Before	After
Control	40	62.85 ± 12.31	54.20 ± 13.72	38.16 ± 9.62	31.46 ± 9.21
Observation	40	63.26 ± 11.54	68.52 ± 10.36	38.76 ± 9.16	42.65 ± 8.92
t		0.154	5.268	0.286	5.520
P value		0.878	0.000	0.776	0.000

SDNN: SD of normal R-R intervals; RMSSD: Root mean square of successive R-R interval differences.

Comparison of inflammatory response indicators between the two patient groups

Prior to examination, no statistically significant difference existed between the two patient groups in IL-6 and TNF-α levels (P > 0.05). Following examination, both IL-6 and TNF-α levels in the observation group were lower than those in the control group (P < 0.05) (Table 3).

Table 3 Comparison of systemic inflammatory response indicators between the two patient groups (mean ± SD, pg/mL).

Group	Patients	IL-6		TNF-α
		Before	After	Before	After
Control	40	3.21 ± 0.85	13.62 ± 3.51	4.21 ± 1.10	9.86 ± 2.31
Observation	40	3.30 ± 0.93	8.77 ± 2.18	4.12 ± 1.05	7.32 ± 1.67
t		0.452	7.424	0.374	5.636
P value		0.653	0.000	0.709	0.000

IL-6: Interleukin-6; TNF-α: Tumor necrosis factor-α.

Comparison of changes in patient-reported outcomes scores before and after examination between the two patient groups

Prior to the examination, no significant differences were observed between the two patient groups across all dimension scores (P > 0.05). Following the examination, the observation group demonstrated higher scores for emotional functioning and overall health than those in the control group, while reporting lower discomfort scores (P < 0.05). Both groups showed increased post-examination discomfort scores, indicating that the CT and injection processes induced notable physical and psychological discomfort (Table 4).

Table 4 Comparison of changes in patient-reported outcomes scores before and after examination in the two patient groups (mean ± SD, score).

Group	Patients	Emotional function		Overall health		Discomfort
		Before	After	Before	After	Before	After
Control	40	66.52 ± 10.15	71.82 ± 11.26	67.97 ± 10.50	72.89 ± 9.38	21.35 ± 6.58	45.64 ± 8.75
Observation	40	65.26 ± 9.59	82.48 ± 10.35	68.53 ± 9.72	88.75 ± 8.27	22.15 ± 7.24	30.53 ± 8.32
t		0.571	4.408	0.248	8.021	0.517	7.915
P value		0.570	0.000	0.805	0.000	0.607	0.000

Comparison of the incidence of procedure-related complications between the two patient groups

The incidence of extravasation and adverse reactions were significantly lower in the observation group than those in the control group (P < 0.05) (Table 5).

Table 5 Comparison of procedure-related complication rates between the two patient groups, n (%).

Group	Contrast medium extravasation	Mild adverse reactions	Moderate to severe adverse reactions	Overall incidence rate
Control	9 (22.50)	8 (20.00)	6 (15.00)	14 (35.00)
Observation	2 (5.00)	5 (12.50)	1 (2.50)	6 (15.00)
χ²	-			4.267
P value	0.048			0.039

DISCUSSION

This study investigated the impact of comprehensive nursing interventions during contrast-enhanced CT for contrast-induced adverse reactions in patients undergoing general surgeries. Findings revealed that in renal function preservation, the observed group exhibited lower increases in serum NGAL (△12.05 ng/mL) and CysC (△0.10 mg/L) than those in the control group (△32.31 ng/mL and △0.19 mg/L), suggesting that precision nursing mitigates early tubular damage caused by iodinated contrast media. The markers NGAL and CysC used in this study demonstrated superior sensitivity to tubular epithelial injury compared with serum creatinine, exhibiting abnormalities 24-48 hours prior to creatinine elevation, thereby facilitating timely detection and intervention[13]. The observation group was administered 800-1000 mL of lukewarm water in divided doses within 2 hours postoperatively, which significantly accelerated contrast agent excretion, reduced tubular exposure time, and consequently lowered oxidative stress and apoptosis[14]. In terms of autonomic nervous system function, the observation group exhibited significantly higher SDNN (68.52 milliseconds) and RMSSD (42.65 milliseconds) values following contrast agent injection than those in the control group (54.20 milliseconds and 31.46 milliseconds, respectively). This indicates that precision nursing helps maintain HRV and alleviates stress-induced autonomic nervous system dysfunction. Reduced HRV frequently indicates an insufficient vagal tone and diminished cardiovascular regulatory capacity, predisposing individuals to arrhythmia onset[9]. In this study, the combination of deep breathing exercises and progressive muscle relaxation during surgery significantly activated the parasympathetic nervous system and alleviated acute stress responses. This finding aligns with the observations of Besson et al[15] in a radiology examination cohort. For postoperative patients with pain and anxiety compounded by autonomic dysregulation, such non-pharmacological psychophysiological interventions are particularly essential[16].

Notably, the HRV measurement window in this study was limited to the period from contrast agent injection to 5 minutes post-injection. This relatively short duration reflects acute physiological stress responses rather than stable autonomic regulation. HRV is known to be affected by factors such as respiratory patterns, body movement, and mental state; therefore, the present results may partly reflect transient perturbations caused by the injection procedure itself rather than long-term autonomic changes. Future studies should consider extended or continuous HRV monitoring to obtain a more comprehensive evaluation of autonomic function.

Regarding systemic inflammatory responses, IL-6 (8.77 pg/mL) and TNF-α (7.32 pg/mL) levels in the observation group were significantly lower than those in the control group (13.62 pg/mL and 9.86 pg/mL, respectively), suggesting that precision nursing interventions were associated with a milder post-procedural inflammatory response; however, causality cannot be firmly established, as reduced inflammation may also be partly due to individual physiological differences or transient stress responses. Nevertheless, the causal relationship should be interpreted with caution. Although the observed reduction in inflammatory cytokines was associated with implementation of precision nursing, it cannot be fully excluded that part of this attenuation resulted from individual physiological variations or transient stress relief rather than direct biochemical modulation by nursing measures. Hydration and psychological support may help improve hemodynamics and reduce stress hormone release. However, further biochemical evidence is needed to confirm the mechanistic link between these interventions and inflammatory pathway inhibition.

This primarily occurs because iodine-based contrast agents activate the complement system (C3a-C5a pathway), induce nuclear factor kappa B translocation in endothelial cells, and release IL-6 and TNF-α, thereby triggering a cascade of inflammatory responses[17]. This study demonstrated that preoperative cognitive behavioral intervention reduced patients’ anxiety levels and decreased the release of stress hormones (such as cortisol and adrenaline), indirectly inhibiting the inflammatory cascade reaction[18]. Concurrently, constant-rate hydration at 1 mL/kg/hour diluted inflammatory mediators by 1.4-fold within 2 hours, accelerating renal clearance[19]. Regarding patients’ subjective experiences, the observation group demonstrated more pronounced improvements in scores for emotional function (increased by 17.22), overall health status (increased by 20.22), and discomfort (decreased by 8.38). Conventional nursing practices prioritize monitoring physiological indicators, such as blood pressure and heart rate, and yet often overlook patients’ psychological experiences. This study incorporates patient perception into an evaluation system, reflecting the modern nursing philosophy of ‘patient-centered care’[20]. Through video education and one-to-one communication, patients’ understanding of the examination process and sense of control were enhanced, effectively alleviating their fear of the unknown[21]. Regarding procedural safety, the contrast medium extravasation (5.00%) and overall adverse reaction (15.00%) rates in the observation group were lower than those in the control group (22.50% and 35.00%, respectively). The nursing team used the 4F scoring model to screen veins prior to puncture and performed a touch-flush-observe cycle on the indwelling needles every 2 hours. Concurrently, real-time monitoring of heart rate, blood pressure, and injection sites was maintained throughout the procedure using an emergency kit containing 0.3 mg epinephrine, 50 mL of 5% glucose solution, and 500 mL of readily available balanced salt solution[22,23]. Results revealed only one case of a grade III rapid-onset reaction, which resolved rapidly within 5 minutes following intravenous epinephrine administration. This incidence was significantly lower than the recent average of 6%-8% reported in three multicenter cohort studies. This outcome may be closely associated with the inclusion of high-risk patients with eGFR of < 60 mL/minute/1.73 m², and the implementation of an individualized strategy involving hydration, pre-warming, and small-dose fractionated infusion[24].

In summary, precision nursing interventions help mitigate early damage to the renal tubules caused by iodinated contrast media, maintain stable autonomic nervous system function, alleviate systemic inflammatory responses, and enhance patients’ subjective comfort and treatment experience. This nursing model effectively reduces the risk of complications during contrast agent administration. Nevertheless, this study has certain limitations as follows: A small sample size derived solely from a single center, absence of long-term follow-up data to assess distant renal function changes, and failure to compare the effects of different contrast agent types[25].

CONCLUSION

Additionally, the short HRV monitoring window and lack of control of respiratory rhythm or mental state during measurement may introduce bias into autonomic function evaluation. Future studies should consider combining continuous HRV tracking with psychological and physiological assessments to capture autonomic dynamics more comprehensively throughout the examination process. Integrating artificial intelligence-assisted predictive modeling with multimodal physiological data, including HRV, inflammatory markers, and psychometric indices, could enable individualized risk stratification and optimize nursing resource allocation. Such approaches may form a foundation for intelligent, precision-driven periprocedural nursing in the practice of radiology. Overall, although this study provided valuable preliminary insights into the role of precision nursing in improving contrast-enhanced CT safety and patient comfort, the findings should be interpreted with caution considering the above methodological limitations.