High-risk factors for delirium in severely ill patients and the application of emotional nursing combined with pain nursing

Abstract

BACKGROUND

Delirium is a neuropsychiatric syndrome characterized by acute disturbances of consciousness with rapid onset, rapid progression, obvious fluctuations, and preventable, reversible, and other characteristics. Patients with delirium in the intensive care unit (ICU) are often missed or misdiagnosed and do not receive adequate attention.

AIM

To analyze the risk factors for delirium in ICU patients and explore the application of emotional nursing with pain nursing in the management of delirium.

METHODS

General data of 301 critically ill patients were retrospectively collected, including histories (cardiovascular and cerebrovascular diseases, hypertension, smoking, alcoholism, and diabetes), age, sex, diagnosis, whether surgery was performed, and patient origin (emergency/clinic). Additionally, the duration of sedation, Richmond Agitation Sedation Scale score, combined emotional and pain care, ventilator use duration, vasoactive drug use, drainage tube retention, ICU stay duration, C-reactive protein, procalcitonin, white blood cell count, body temperature, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and Sequential Organ Failure Assessment score were recorded within 24 h after ICU admission. Patients were assessed for delirium according to confusion assessment method for the ICU, and univariate and multivariate logistic regression analyses were performed to identify the risk factors for delirium in the patients.

RESULTS

Univariate logistic regression analysis was performed on the 24 potential risk factors associated with delirium in ICU patients. The results showed that 16 risk factors were closely related to delirium, including combined emotional and pain care, history of diabetes, and patient origin. Multivariate logistic regression analysis revealed that no combined emotional and pain care, history of diabetes, emergency source, surgery, long stay in the ICU, smoking history, and high APACHE II score were independent risk factors for delirium in ICU patients.

CONCLUSION

Patients with diabetes and/or smoking history, postoperative patients, patients with a high APACHE II score, and those with emergency ICU admission need emotional and pain care, flexible visiting modes, and early intervention to reduce delirium incidence.

Key Words: Critical illness; Delirium; Risk factor; Intensive care unit; Emotional nursing; Pain nursing

Core Tip: Delirium incidence in intensive care unit (ICU) patients remains high and seriously affects their prognosis. To reduce the incidence of delirium in ICU patients, medical staff should be fully aware of delirium in critically ill patients and intervene it promptly. Medical staff should focus on the influence of combined emotional and pain care on delirium occurrence and establish individualized flexible visitation modes according to the patient’s situation. We found that history of diabetes, smoking history, emergency referral to the ICU, surgery, long stay in the ICU, and high Acute Physiology and Chronic Health Evaluation II score were identified to be risk factors for delirium in critically ill patients.

INTRODUCTION

Delirium, also known as acute brain syndrome, is characterized by disorientation, recent memory loss, and attention deficits. Delirious individuals have difficulty focusing, maintaining, or shifting their attention. These symptoms appear suddenly within a few hours or days[1]. These conditions fluctuate throughout the day and usually worsen at night (known as sunset phenomenon)[2]. These symptoms are short in duration and rarely last for more than a month. Delirium is not a disease but a clinical syndrome caused by a variety of factors. As a transient state of confusion caused by many factors, delirium manifests as a disturbance of consciousness and changes in cognitive function, with mental symptoms being the major manifestation[3]. The level of consciousness of patients with delirium varies, and the content of consciousness is disorganized, which is the result of the joint action of systemic disease and brain function. Delirium is often reversible and can appear within a few hours or days. Various factors are associated with delirium, such as medication, environment, and disease status. Comatose patients may experience delirium before regaining consciousness. Delirium can be divided into excitatory, inhibitory, and mixed types[4-6]. Excitatory delirium is characterized by agitation, restlessness, and attempts to remove tubes. Depressive delirium is characterized by apathy, impaired speech, and lethargy. The mixed type is typical of manifestations of both the above two types. The proportions of different subtypes of delirium in patients with severe disease vary significantly. Delirium is usually a sign of serious illness[7,8], with the cause being often an underlying condition. Delirium can be very serious, and around 15%-40% of hospitalized patients with delirium die within a month. Therefore, timely identification and treatment of delirium are extremely important[9]. A delirious person, if found untreated, should be immediately referred to a hospital. Treatment should be the first priority if another illness is found to be associated with delirium. Medications that could have potentially caused delirium should be discontinued. Approximately 35% of patients with delirium in the intensive care unit (ICU) are missed or misdiagnosed, and most patients do not receive adequate attention and corresponding management or treatment[10,11].

Emotional nursing, primarily through the language, expression, posture, attitude, behavior, and temperament of the nursing staff, affects and improves patients’ mood, and relieves their concerns and troubles, so as to enhance their will and confidence to overcome the disease and reduce or eliminate the pain caused by various bad emotions and behaviors[12,13]. The various physical symptoms caused by these factors allow patients to receive treatment and care in the best psychological state to achieve early recovery. Patients with severe patients have a complex, changeable, and relatively high risk. Most patients experience a series of bad moods and poor sleep quality due to concerns about disease development, family economic burden, and pain. In routine nursing, clinical nurses often simply pursue of the execution of medical orders but ignore the mental health of patients. In recent years, holistic nursing has received increasing attention. In the current nursing system, psychological nursing has become an indispensable link in basic nursing, particularly in the context of emotional nursing[14-16].

This study conducted a regression analysis to screen out the risk factors that affect the occurrence of delirium to provide data support for clinical staff to identify the risk factors for delirium in critically ill patients early and take effective measures to manage delirium in time. The influence of emotional nursing combined with pain nursing on delirium was also examined.

MATERIALS AND METHODS

This retrospective study was approved by the ethics committee of Fourth Affiliated Hospital of Soochow University (Suzhou Dushu Lake Hospital, China). All the patients signed an informed consent form before inclusion in the study.

Patient recruitment and selection criteria

We enrolled patients who were referred to or admitted to our emergency ICU because of serious illness between December 2020 and June 2023. The inclusion criteria were as follows: (1) Met the relevant diagnostic criteria in “Intensive Care Specialist Nursing”; (2) Age ≥ 18 years; (3) ICU retention time ≥ 24 h; and (4) Non-cardiac surgery patients. The exclusion criteria were: (1) Combined with spiritual illness; (2) Patients that remained in coma after admission to ICU; and (3) There was hearing impairment.

Study design

This was a retrospective study in which critically ill patients admitted to the emergency ICU of the Fourth Affiliated Hospital of Soochow University between January 1, 2020 and December 30, 2023 were selected.

The main contents of emotional nursing include: (1) Relaxing mentality: Providing patients with a comfortable environment and reducing the impact of environmental stimuli such as noise; (2) Empathy: Understanding the patient’s personal preferences, maintaining communication with the patient, and avoiding excessive attention to the disease; and (3) Emotional guidance: Establishing a good nurse-patient relationship, channeling patients’ bad emotions, and reducing their psychological burden.

The main measures of pain care include: (1) Pain care: The information of the patient’s previous pain duration and pain degree was collected to provide reference for subsequent analgesia measures. When the pain occurred, the patients were instructed to distract their attention by listening to music, reading books or newspapers, etc. And the patients were taught to relax. Massage, hot compress, and other measures can also be used to help patients relieve pain; and (2) Diet and daily life guidance: If the degree of pain was mild after surgery, the patient would be instructed to take oral compound vitamin B and other drugs to assist pain relief. At the same time, the patient was instructed to exercise.

Clinical variable selection

Based on the results of several systematic reviews at home and abroad, data related to delirium in ICU patients were selected for analysis. Data were collected using an electronic medical record information system and patient medical records. The finally included factors were as follows: (1) General information: Sex, age, smoking history, hypertension history, diabetes history, and heart disease history; (2) Disease factors: Acute physiology and chronic health evaluation II (APACHE II) score, GCS score, infection, respiratory failure, hypoxemia, etc. The APACHE II and GCS scores were evaluated within 24 h after admission to the ICU; (3) Treatment factors: Surgery, invasive mechanical ventilation, length of stay, sedatives, glucocorticoids; and (4) Laboratory indicators: White blood cell count, procalcitonin, C-reactive protein, albumin, acid-base imbalance, alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, etc.

Delirium assessment

The degree of sedation and consciousness was assessed using the Richmond Agitation Sedation Scale (RASS) score. Patients were then assessed for delirium according to the confusion assessment method for the ICU (CAM-ICU), a combination of timing and situational modalities, twice a day (8:00 and 20:00). All patients were screened and assessed for delirium using the CAM-ICU, while delirium was assessed and recorded at any time as the patient’s ideology changed. RASS, CAM-ICU, and APACHE II scores were used to evaluate delirium.

Statistical analysis

Statistical analyses were performed using Prism software (version 7.0). Measurement data are expressed as the mean ± SD, and comparison of data conforming to a normal distribution was performed using the t test. Count data are expressed as percentages (%) and were compared using the χ² test. The risk factors for delirium were determined via univariate and multivariate logistic regression analyses, with odds ratios (ORs) and 95% confidence intervals (CIs) calculated. P < 0.05 was considered statistically significant.

RESULTS

Patient characteristics

A total of 301 patients were included in the study, including 184 men and 117 women, with an average age of (64.73 ± 16.03) years. Emergency source accounted for 48.84% of the 147 cases. The sources of the department were general surgery (n = 188), oncology (n = 46), obstetrics and gynecology (n = 5), general medicine (n = 30), and orthopedic surgery (n = 32).

Factors affecting delirium

As presented in Table 1, combined emotional and pain care, history of diabetes, smoking, alcoholism, renal insufficiency, use of vasoactive drugs, indentured drainage tube, patient origin (emergency/outpatient), surgery, ventilator use time, ICU admission time, C-reactive protein level within 24 h of ICU admission, APACHE II score, Sequential Organ Failure Assessment score, sedative use time, and RASS score were significantly associated with delirium (P < 0.05), while age, sex, hypertension, heart disease, body temperature, white blood cell count, and calcium intake had no significant association with delirium (P > 0.05).

Table 1 Univariate analysis of risk factors for delirium in intensive care unit patients, n (%).

Variable	Delirium group (n = 102)	Non-delirium group (n = 199)	χ2/t	P value
Combined emotional and pain care	42 (41.18)	108 (54.27)	4.625	0.032
Diabetes history	37 (36.27)	39 (19.60)	9.937	0.002
Patient source (emergency)	75 (73.53)	72 (36.18)	37.650	< 0.001
Surgery	80 (78.43)	183 (91.96)	11.190	0.001
Smoking history	59 (57.84)	62 (31.16)	19.980	< 0.001
Alcoholism history	35 (34.31)	38 (19.10)	8.501	0.004
Renal insufficiency	39 (38.24)	19 (9.55)	35.680	< 0.001
Use of vasoactive drugs	78 (76.47)	82 (41.21)	33.680	< 0.001
Placement of an indwelling drainage tube	101 (99.02)	180 (90.45)	7.465	0.006
Ventilator time (h)	70.85 ± 7.01	20.33 ± 1.70	9.068	< 0.001
ICU stay (d)	6.23 ± 0.52	2.07 ± 0.14	9.834	< 0.001
C-reactive protein level (mg/L)	165.70 ± 10.14	123.20 ± 7.82	3.364	< 0.001
Length of sedative medication (h)	56.67 ± 5.56	17.01 ± 1.08	9.218	< 0.001
APACHE II score	16.42 ± 0.36	12.19 ± 0.26	9.439	< 0.001
SOFA score	6.81 ± 0.28	4.55 ± 0.18	7.124	< 0.001
RASS score	-3.86 ± 0.04	-3.72 ± 0.05	2.011	0.045

ICU: Intensive care unit; APACHE: Acute Physiology and Chronic Health status assessment; SOFA: Sequential Organ Failure Assessment; RASS: Richmond Agitation Sedation Scale.

Multivariate logistic regression analysis

Table 2 presents the results of the multivariate analysis. Combined emotional and pain care, smoking history, emergency surgery, emergency transfer to ICU, surgery, long stay in ICU, and high APACHE II score were identified to be independent risk factors for delirium in critically ill patients (P < 0.05).

Table 2 Multivariate analysis of risk factors for delirium in intensive care unit patients.

Variable	OR	95%CI	P value
Combined emotional and pain care	0.351	0.146-0.845	0.020
Diabetes history	4.631	1.787-11.999	0.002
Patient source (emergency)	0.308	0.118-0.802	0.016
Surgery	6.250	1.459-26.772	0.014
ICU stay	1.659	1.240-2.219	0.001
Smoking history	2.787	1.094-7.100	0.032
APACHE II score	1.421	1.246-1.621	< 0.001

95%CI: 95% confidence interval; OR: Odds ratio; ICU: Intensive care unit; APACHE: Acute Physiology and Chronic Health status assessment.

Effect of combined emotional and pain care on incidence of delirium

Multivariate logistic regression analysis showed that the risk of delirium in critically ill patients who received combined emotional and pain care was only 1/3 of that in patients who did not. A total of 301 patients were included in this study. Among the 151 patients who did not use emotional nursing and pain nursing, 60 developed delirium, with an incidence of 39.74%; among the 150 patients who received combined emotional and pain nursing, 42 developed delirium, with an incidence of 28.00%. The incidence of delirium in patients receiving emotional nursing combined with pain nursing was significantly lower than those not receiving (χ² = 0.59, P < 0.05). There was no significant difference in sex or age between the patients who received combined emotional and pain nursing and those who did not (P > 0.05), as shown in Table 3.

Table 3 Comparison of clinical data and incidence of delirium between patients with and without combined emotional and pain care, n (%).

Characteristics	Patients with combined emotional and pain care (n = 150)	Patients without combined emotional and pain care (n = 151)	χ2	P value
Age			0.033	0.855
< 65 years	86 (57.3)	85 (56.3)
≥ 65 years	64 (42.7)	66 (43.7)
Sex			2.506	0.113
Male	85 (56.7)	99 (65.6)
Female	65 (43.3)	52 (34.4)
Delirium			4.625	0.032
Yes	65 (43.3)	60 (39.7)
No	108 (72.0)	91 (60.3)

DISCUSSION

In this study, logistic regression analysis was performed on the risk factors that may affect delirium in ICU patients, and it was found that no use of combined emotional and pain care, history of diabetes, history of smoking, emergency admission, surgery, long stay in the ICU, and high APACHE II score were associated with delirium in ICU patients.

This study further analyzed four important factors: Combined emotional and pain care, emergency transfer, ICU stay time, and diabetes history. Previous studies have suggested that the duration and frequency of combined emotional and pain care in ICU patients may affect the occurrence of delirium[17-19]. To date, no domestic study has reported the effects of combined emotional and pain care on delirium in ICU patients. This study found that the incidence of delirium in critically ill patients without combined emotional and pain care was 3.5 times higher than that of patients receiving combined emotional and pain care. Compared to ordinary wards, the closed management mode of the ICU brings patients separated anxiety, and combined emotional and pain care can bring patients a certain sense of security and comfort. Combined emotional and pain care can alleviate patients’ negative emotions during treatment and play a role in protecting the body under stress. These results suggest that in addition that the medical staff needs to master sufficient theoretical knowledge and practical skills, the nursing model is also an essential and important factor for the prevention of delirium in ICU patients. It is important that medical personnel should establish a more scientific and humanized detection mode according to the individual needs of the patients.

This study also found that the risk of delirium in patients undergoing emergency surgery was three times higher than that of patients not undergoing. Compared to those who were not transferred to the emergency room, patients who were transferred to the emergency room experienced fast, rapidly changing, and intense mental stimulation. Lack of sufficient preoperative communication, such as pain, body constraints, and vision systems, can cause intense fear and anxiety. Negative emotions can induce various stressful reactions and increase the incidence of delirious errors[20]. Therefore, medical staff should strengthen psychological care for patients who are transferred to the ICC to prevent and reduce the incidence of delirium in the early stages of psychological intervention, thereby decreasing the psychological stress response of the patient after admission to the ICU.

Owing to the particularity of ICU work needs, ICU patients are often disturbed by various sounds, lights, and treatment measures, making awake patients unable to ensure normal effective sleep. Studies have shown that sleep disorders are closely related to the occurrence of delirium in ICU patients[21,22]. In this study, the probability of delirium increased by 1.659 times (OR = 1.659) for each additional day of ICU stay. This suggests that medical staff should pay more attention to patients who need to stay in the ICU for a long time because of their illness, especially to ensure effective sleep of patients at night, reduce the stimulation of sound and light on patients, centralize treatment measures under the premise of ensuring patient safety, and improve patients’ sleep by using earplugs and eye masks, and listening to soothing music. If necessary, drugs should be administered to assist sleep according to the patient’s condition.

The results of this study also suggest that the risk of developing delirium in patients with diabetes is approximately 4.6 times that of patients without. Diabetes can damage the cardiovascular system; patients who have been ill for many years often experience varying degrees of cerebrovascular and nerve damage, resulting in poor concentration and memory loss[22,23]. In the clinical work of ICU, the evaluation and prevention of delirium in patients with diabetes should be strengthened, blood glucose changes should be closely monitored, hypoglycemic drugs should be used rationally, and irreversible damage to the cardiovascular and cerebrovascular system caused by hyperglycemia or hypoglycemia should be avoided.

There are certain limitations in this study. The sample size of this study is not large enough and it is a single-center study, so the results are not sufficiently responsive to the real world and the results are not highly universal. High-quality randomized controlled studies are needed to support these results.

CONCLUSION

The incidence of delirium in ICU patients remains high and seriously affects their prognosis. To reduce the incidence of delirium in ICU patients, medical staff should be fully aware of delirium in critically ill patients and intervene it promptly. The results of this study suggest that medical staff should pay more attention to the influence of the nursing model on the occurrence of delirium in patients and establish individualized and flexible visitation modes according to the patient’s situation. In addition, the results of this study show that a history of diabetes, smoking, emergency referral to the ICU, postoperative surgery, long stay in the ICU, and high APACHE II score are also risk factors for delirium in critically ill patients.