Turkish neonatal nurses’ knowledge regarding the enteral feeding in preterm infants: a descriptive, cross-sectional study

Abstract

Background

Neonatal nurses play a key role in the safe and effective enteral feeding of preterm infants, but their knowledge and practices in this specific area remain largely unexamined. This study sought to evaluate neonatal nurses’ knowledge levels and practices concerning enteral feeding in preterm infants.

Methods

A total of 300 neonatal intensive care nurses working in 8 hospitals in Istanbul, Türkiye were included in this descriptive cross-sectional study. Data were collected using a sociodemographic information and enteral feeding practices form and an enteral feeding knowledge questionnaire. The 40-item enteral feeding knowledge questionnaire yields a total score ranging from 0 to 100, with higher scores indicating a higher knowledge level. Based on a 6-expert panel review, the content validity index (CVI) of the questionnaire was 0.94.

Results

The mean knowledge score was 67.12 out of 100 (SD, 8.83; range, 45–85). Older age (P = .001), longer NICU experience (P = .003), higher education level (P = .043), and having NICU nursing certification (P = .001) were associated with significantly higher knowledge levels. Correct response rates were particularly low for items about the selection of appropriate catheter size in preterm infants with extremely low birth weight, infant positioning during catheter insertion and feeding, the necessity of verifying catheter placement before each feeding, the method used to confirm correct catheter placement, feeding flow rate, assessment of gastric residuals, and maintenance of asepsis. None of the participating nurses’ NICUs used a standard protocol for enteral feeding in preterm infants.

Conclusion

The research findings point to the necessity of supporting nurses with evidence-based information on enteral feeding practices, ensuring the standardization of clinical practices, and managing enteral feeding in accordance with current guidelines.

Background

The development of oral feeding skills in preterm infants begins in the intrauterine period with the synchronous interaction of various physiological and biological processes [1] and continues in the postnatal period as the neurological, gastrointestinal, cardiorespiratory, and oral-motor systems function both independently and in harmony with each other [2]. As preterm infants have not reached a sufficient level of maturity anatomically and physiologically, this intersystem harmony may not be achieved [1, 3, 4]. Therefore, enteral feeding is provided through an orogastric (OG) or nasogastric (NG) tube until preterm infants are mature enough for oral feeding [5, 6]. Enteral feeding is a safe and effective method that allows food to be delivered directly to the stomach via the OG or NG catheter to meet preterm infants’ daily energy and nutritional needs [7, 8]. This method is also preferred in order to prevent complications that can occur with prolonged parenteral nutrition [9], to support intestinal development, and to allow the enteral administration of pharmacological agents [8, 10, 11].

Neonatal nurses have a critical role in the safe and effective provision of enteral feeding [11, 12].This role includes responsibilities such as inserting OG/NG catheters in line with evidence-based guidelines, checking their placement, administering food ordered by the neonatologist using correct feeding techniques, ensuring aseptic care, monitoring the physiologic stability of the preterm infant during feeding, providing oral motor stimulation to support feeding, and informing the physician in a timely manner in the event of complications [11–14]. Preterm infants are more susceptible to potential complications from enteral feeding due to their underdeveloped anatomy and physiology [15]. In addition to this susceptibility, failure of neonatal nurses to fulfill any of their critical responsibilities related to enteral feeding may increase preterm infants’ risk of serious complications such as aspiration pneumonia [16], feeding intolerance [17], necrotizing enterocolitis [18, 19], regurgitation, and sepsis [9]. The literature includes previous studies examining the knowledge levels and practices related to enteral feeding among nurses working in adult [20–22] and pediatric populations [23]. However, very few studies have investigated neonatal nurses’ knowledge and practices concerning enteral feeding for preterm infants [24, 25]. Moreover, these studies encompassed only a two-day observation of neonatal nurses’ enteral feeding practices [25] or assessment of neonatal nurses’ knowledge levels about the indications and contraindications of enteral interventions [24]. Considering the importance of safe enteral feeding in preterm infants, the critical responsibilities neonatal nurses have in this process, and the varying evidence-based practices implemented in different countries and neonatal intensive care units (NICUs), it is necessary to comprehensively evaluate nurses’ knowledge and skills in this area [12, 20].

Research questions

• To what degree does neonatal nurses’ knowledge about enteral feeding in preterm infants align with evidence-based practices?

• What factors influence neonatal nurses’ level of knowledge about the enteral feeding of preterm infants?

Methods

Sample

This descriptive cross-sectional study was conducted with neonatal intensive care nurses in Istanbul, Türkiye to determine their knowledge levels and practices related to the enteral feeding of preterm infants. Data collection took place between October 2024 and March 2025 in eight different research and training hospitals serving central Istanbul under the administration of the Turkish Ministry of Health. The hospitals all provide level 3 neonatal intensive care services and have similar characteristics.

Neonatal nurses working in the NICUs of these centers participate in a standard 2-month (186-hour) training program on the care and feeding of preterm infants, provided collaboratively by the NICU charge nurse, senior nurses, and a nurse educator. Preterm infants are gradually transitioned from parenteral to enteral nutrition under joint management by a neonatologist and neonatal nurse, during which the infants’ indications for enteral feeding are assessed regularly. The neonatologist determines feeding frequency and amount based on each preterm infant’s clinical condition. Neonatal nurses are responsible for providing enteral feeding using evidence-based methods; monitoring infants’ physiological responses during feeding; managing feeding duration; ensuring appropriate positioning; assessing enteral feeding tolerance and signs of potential food intolerance; and monitoring growth parameters (e.g., body weight, height, head circumference). Gastric residuals are not routinely checked in these centers; however, in preterm infants exhibiting signs of feeding intolerance, residuals may be monitored by the neonatal nurse upon request by the neonatologist. Enteral feeding is implemented using an individualized developmental care approach, with the process evaluated jointly by the neonatologist and nurse according to each infant’s clinical condition and feeding tolerance.

Participants were recruited from among the neonatal nurses staffing the NICUs of the eight hospitals using random sampling. Inclusion criteria were: permanent, full-time employment in the NICU, direct involvement in neonatal care, Turkish literacy and fluency, voluntary participation, and provision of informed consent. A total of 316 nurses from the participating centers were eligible for the study. Of these, 16 were excluded due to unwillingness to participate (n = 5), being on maternity leave during the study (n = 8), or other reasons (n = 3). As a result, the sample comprised 300 neonatal nurses (94.9% of the target population). Post hoc analysis (G*Power v 3.1.9) indicated that with a sample size of 300 neonatal nurses, alpha error level of 0.05, and effect size (w) of 0.20, the study power (1–β) was 0.93. This indicated adequate sample size and power (≥ 0.80) [26].

Ethical considerations

The study was approved by the Ethics Committee of Health Sciences University in Istanbul, Türkiye (Ethical Review Number: 224.364.IRB3.151) and conducted in accordance with the Declaration of Helsinki (clinical trial number: not applicable). Written permission to conduct the study was obtained from the eight sampled hospitals. Written and verbal informed consent was obtained from all nurses before their participation in the study.

Instruments

Data collection was carried out using a sociodemographic information and enteral feeding practices form and an enteral feeding knowledge questionnaire for neonatal nurses, both of which were developed by the researchers based on the relevant literature.

Sociodemographic information and enteral feeding practices form

The form included a total of seven questions. Five of the questions concerned background information about the participant: their age, sex, education level, years of full-time experience in the NICU, and whether they had neonatal intensive care nursing certification. The remaining questions were about their enteral feeding practices: whether their NICU had a standard protocol for the steps of feeding via OG/NG catheter and how OG/NG catheter insertion length was measured in their unit.

Enteral feeding knowledge questionnaire for neonatal nurses

This questionnaire was created by the investigators to measure neonatal nurses’ knowledge of evidence-based practices for the enteral feeding of preterm infants. Before creating the questionnaire, the researchers conducted a comprehensive literature review on the principles of safe, evidence-based enteral feeding in preterm infants to create a theoretical framework and item pool. A literature search was conducted using the keywords “preterm,” “low-birth-weight infants,” “enteral feeding,” “nasogastric and/or orogastric catheters,” “evidence-based practice,” “knowledge,” “neonatal intensive care,” and “neonatal nurses” in databases such as Scopus, Web of Science, PubMed, Science Direct, and CINAHL. No valid and reliable measurement tool was found in the literature to assess neonatal nurses’ knowledge of enteral feeding practices in preterm infants. Therefore, relevant literature was utilized to develop a draft questionnaire [8, 10–12, 14, 25, 27–30].

The initial 42-item draft questionnaire was reviewed by a panel of six experts with doctoral degrees in neonatal and pediatric nursing. These six nurse experts evaluated the content validity of the questionnaire by rating the items from highly relevant (4) to not relevant (1) according to the Davis technique. The content validity index (CVI) of each item was calculated as the ratio of experts who rated the item as 3 or 4 to the total number of experts [31], and the CVI of the entire questionnaire was obtained by averaging these values. The CVI of the draft questionnaire was 0.92. Based on expert feedback, the questionnaire was revised by removing two items with a CVI lower than 0.80 and two items evaluated as duplicates of other items. The modified version was reevaluated by the same expert panel and required no further changes. For the final questionnaire, the item-level CVI ranged from 0.83 to 1.00 and the scale-level CVI was 0.94. Additionally, a pilot study for the final questionnaire was conducted with 10 neonatal nurses who met the sampling criteria but were not included in the main sample. The findings of the pilot study indicated that the participants found the questionnaire items clear and comprehensible.

The final questionnaire included 40 items (see Table 2), each consisting of one true or false statement which the participants are asked to agree or disagree with in order to evaluate their knowledge. The nurses’ responses were determined to be correct or incorrect based on the answer key, and they received 2.5 points for each correct response (0 points for incorrect responses). Total scores range from 0 to 100, with higher scores indicating a higher knowledge level. The form was utilized for the first time in the present study.

Table 2.

Distribution of correct responses on the enteral feeding knowledge questionnaire (n = 300)

Items	Correct responses
	n	%
1. Sterile gloves must be worn when inserting an NG/OG catheter. (False)	233	77.7
2. The NG/OG catheter is only used for intermittent feeding. (False)	234	78.0
3. For infants weighing < 1000 g, a size 6–8 Fr NG/OG tube is selected. (False)	89	29.6
4. When inserting NG/OG catheters, the patient’s head is elevated 30–45 degrees. (False)	59	19.7
5. Food is delivered under pressure using the injector plunger. (False)	255	85.0
6. The injector is held 20 cm above the level of the infant’s stomach to allow the food in the injector to flow by gravity into the stomach. (True)	276	92.0
7. The amount of food is increased as the infant tolerates it. (True)	277	92.3
8. For preterm and low-birth-weight infants, the flow rate is calculated as 15–20 mL in 5 min. (False)	36	12.0
9. For infants weighing ≥ 1000 g, a size 10–12 Fr NG/OG catheter is selected. (False)	255	85.0
10. NG/OG catheter position is continuously evaluated once every 24 h. (False)	89	29.6
11. In patients with an NG/OG catheter, the catheter is rotated on its axis 3–4 times a day to prevent the catheter from adhering to the gastrointestinal tract. (False)	109	36.3
12. To confirm the placement of the NG/OG catheter in very small preterm infants, 1–2 mL of air is injected through the catheter before each feeding and a stethoscope is used to hear it entering the stomach. (False)	79	26.3
13. NG/OG catheter insertion is attempted a maximum of three times. If unsuccessful, help is sought from another healthcare professional. (True)	270	90.0
14. The NG/OG probe is changed every 72 h. (False)	183	61.0
15. The frequency of NG/OG catheter changes is not affected by the infant’s lying position. (False)	142	47.3
16. The temperature of the food given by NG/OG catheter is 16–20 °C. (False)	172	57.3
17. The size of NG/OG catheter is selected in proportion to the infant’s weight. (True)	292	97.3
18. Infants weighing less than 1000 g are fed at 2-hour intervals. (True)	231	77.0
19. After each feeding, 1–2 mL of sterile water/air should be given to wash out the NG/OG catheter. (True)	208	69.3
20. Routine gastric residual checks are performed before each feeding via the NG/OG catheter. (False)	147	49.0
21. NG/OG catheter nose/mouth fixation tape is changed daily. (True)	234	78.0
22. Routine residual checks help regulate natural hydrochloric acid production in the stomach. (False)	186	62.0
23. If gastric residual volume is less than 5 mL/kg, it is returned to the stomach. (True)	236	78.7
24. The injector used for feeding and checking residuals is washed after each use and changed daily. (False)	143	47.7
25. Infants weighing more than 1000 g are fed at 4-hour intervals. (False)	242	80.7
26. As the NG/OG catheter set increases vagal stimulation, it may cause apnea and bradycardia. (True)	263	87.7
27. Gastric residual that is green should always be discarded. (False)	90	30.0
28. The NG/OG catheter should be removed between feedings. (False)	225	75.0
29. Neonates may feel pain and discomfort when the NG/OG catheter is inserted. (True)	274	91.3
30. If gastric residual volume is > 5 mL/kg, feeding is continued. (False)	189	63.0
31. Before inserting the NG/OG catheter, it is lubricated with sterile water. (True)	158	52.7
32. After an NG/OG catheter is replaced, the securement tape should be placed at different sites to prevent skin damage. (True)	249	83.0
33. The gold standard method to ensure correct NG/OG catheter placement is gastric content aspiration and pH testing. (False)	101	33.7
34. Not advancing the NG/OG catheter far enough leads to risk of aspiration and pneumonia in the infant. (True)	273	91.0
35. Advancing the NG/OG catheter too far causes malabsorption. (True)	273	91.0
36. Oral feeding can be attempted when the infant can tolerate 60%–100% of the food given. (True)	212	70.7
37. Prolonged NG/OG feeding delays the development of oral motor skills. (True)	272	90.7
38. The NG/OG catheter should be removed between feedings. (False)	252	84.0
39. Oral-motor interventions should not be applied during the NG/OG feeding process. (False)	198	66.0
40. Gastric residual is checked when there is abdominal distension or increased abdominal circumference. (True)	286	95.3

Procedure

The researchers informed the nurses of the aim and importance of the study, then obtained their written informed consent to participate. The nurses filled out the data collection forms themselves, which took approximately 15–20 min, while working in the NICU. Each nurse completed the data collection forms independently, and no compensation was provided by the researchers for their participation. Their responses to the enteral feeding knowledge questionnaire were evaluated later using the answer key.

Data analysis

The study data were analyzed using a licensed copy of IBM SPSS Statistics for Windows version 26.0. The Shapiro-Wilks test and box plots were used to test continuous variables for normal distribution. Mean and standard deviation or frequency and percentage were used as descriptive statistics. The mean knowledge scores of the neonatal nurses were compared according to their age, sex, education, years of NICU experience, and whether they had neonatal nursing certification. For data showing a normal distribution, Student’s t-test was used for pairwise comparisons and one-way analysis of variance (ANOVA) with post hoc Bonferroni correction was used for comparisons among three or more groups. The results were evaluated within 95% confidence intervals and p values < 0.05 were considered statistically significant.

Results

Sample characteristics

The participating neonatal nurses had a mean age of 32.82 ± 7.15 years (range, 20–55 years) and their time working in the NICU varied between 1 and 35 years with a mean of 8.76 ± 6.37 years. Most participants were female (n = 274, 91.3%) and held a bachelor’s degree 60.7% (n = 182). Nearly a third were certified in NICU nursing (n = 98, 32.7%). There was no standard protocol regarding enteral feeding in the participants’ units, but 58.3% (n = 175) of the neonatal nurses reported that they measured the OG/NG insertion length from the nose-earlobe-xiphoid (NEX) method and 41.7% (n = 125) used the nose-earlobe-mid-umbilicus (NEMU) method (Table 1).

Table 1.

Demographic data of the participants (n = 300)

Characteristics		n (%)
Age	Mean ± SD	32.82 ± 7.15
	Median (Range)	31 (20–55)
	< 30 years	130 (43.3)
	30–39 years	117 (39.0)
	≥ 40 years	53 (17.7)
Sex	Female	274 (91.3)
	Male	26 (8.7)
Education level	High school	37 (12.3)
	Associate’s degree	33 (11.0)
	Bachelor’s degree	182 (60.7)
	Postgraduate degree	48 (16.0)
NICU experience	Mean ± SD	8.76 ± 6.37
	Median (Range)	7 (1–35)
	1–2 years	41 (13.7)
	3–5 years	77 (25.7)
	6–10 years	90 (30.0)
	≥ 11 years	92 (30.6)
NICU nursing certification	Yes	98 (32.7)
	No	202 (67.3)
Enteral feeding protocol in NICU	Yes	0 (0.0)
	No	300 (100)
Insertion length measurement method	NEX*	175 (58.3)
	NEMU**	125 (41.7)

*Nose-earlobe-xiphoid, **Nose-earlobe-mid-umbilicus

Neonatal nurses’ knowledge of enteral feeding

Table 2 shows the distribution of nurses who answered each item correctly and incorrectly. The five items with the highest correct response rates were item 17 (97.3%), item 40 (95.3%), item 7 (92.3%), item 6 (92.0%), and item 29 (91.3%). More than half of the nurses (range, 52.7%–97.3%) correctly responded to the items related to NG/OG catheter placement and preparation, catheter selection, feeding techniques, feeding tolerance, and complications. These items included catheter placement and preparation (items 1, 13, 14, 21, 31, and 32), catheter selection (items 9 and 17), feeding techniques (items 2, 5, 6, 16, 19, 28, 38, and 39), feeding tolerance (items 7, 18, 22, 23, 25, 30, 36, and 40), and complications (items 26, 29, 34, 35, and 37) (Table 2).

The five items with the lowest correct response rates were item 8 (12.0%), item 4 (19.7%), item 12 (26.3%), and items 3 and 10 (29.6% for each). More than half of the nurses (range, 51.0%–88.0%) responded incorrectly to items about checking NG/OG catheter placement (items 10, 12, and 33), checking gastric residuals (items 20, 24, and 27), catheter selection for infants weighing less than 1000 g (item 3), infant positioning during feeding, rotating the catheter, and the feeding techniques to evaluate food flow rate (items 4, 8, 11, and 15) (Table 2).

The mean score on the knowledge of enteral feeding questionnaire was 67.12 ± 8.83 out of 100 (range, 45.0–85.0).

Differences in enteral feeding knowledge according to descriptive characteristics

Comparing enteral feeding knowledge scores by sex revealed no significant difference, with mean knowledge scores of 67.23 ± 9.08 for women and 64.9 ± 8.99 among the male neonatal nurses in the study (P = .213; Table 3).

Table 3.

Comparison of enteral feeding knowledge scores according to descriptive characteristics (n = 300)

		Knowledge Score		P
		Mean ± SD	Median (Range)
Sex	Female	67.23 ± 9.08	67.5 (45–85)	a.213
	Male	64.9 ± 8.99	63.8 (50–80)
Age	< 30 years	65.00 ± 8.97	65 (45–82.5)	b.001**
	30–39 years	68.42 ± 8.73	70.0 (45–85)
	≥ 40 years	69.47 ± 7.63	67.5 (52.5–85)
Education level	High school	64.18 ± 8.99	65 (45–80)	b.043*
	Associate’s degree	67.01 ± 8.89	67.5 (45–85)
	Bachelor’s degree	67.27 ± 8.80	67.5 (45–80)
	Postgraduate degree	69.68 ± 7.97	70 (50–82.5)
NICU experience	1–2 years	63.59 ± 9.55	65 (45–77.5)	b.003**
	3–5 years	65.94 ± 9.91	67.5 (45–85)
	6–10 years	67.46 ± 7.83	70 (45–85)
	≥ 11 years	69.34 ± 7.88	70 (47.5–85)
NICU nursing certification	Yes	69.54 ± 7.58	70 (47.5–85)	a.001**
	No	65.95 ± 9.17	67.5 (45–85)

^aStudent’s t test, ^bOne-way ANOVA *P < .05, **P < .01

However, enteral feeding knowledge scores differed significantly when compared according to age group (P = .001), with post hoc Bonferroni tests showing that neonatal nurses younger than 30 years of age had significantly lower scores than the other groups (P < .01; Table 3). There was no significant difference in knowledge scores between neonatal nurses aged 30–39 years and those 40 and older (P > .05).

The comparison of enteral feeding knowledge scores according to educational status also demonstrated a significant difference among the groups (P = .043). Post hoc Bonferroni analysis indicated that knowledge scores were significantly lower in nurses whose highest level of education was high school compared to those with graduate degrees (P = .027; Table 3).

Enteral feeding knowledge scores also differed significantly according to years of NICU experience (P = .003), with lower scores among neonatal nurses with 1 to 2 years of experience compared to those working in the NICU for 6 to 10 years (P = .035) and 11 years or more (P = .003), as well as among neonatal nurses with 3 to 5 years of experience compared to those with 11 years or more (P = .046). In addition, the enteral feeding knowledge scores of participants with NICU nursing certification were significantly higher than those of nurses without this certification (P = .001; Table 3).

Discussion

Providing safe and effective enteral feeding to preterm infants contributes directly not only to the physiological support of their growth and development, but also to improved long-term health outcomes [16, 32]. Therefore, neonatal nurses’ levels of evidence-based knowledge and practical skills [24, 25] play a decisive role in safe enteral feeding [20, 22], maintaining clinical stability [10], and preventing possible complications [11, 12]. This study evaluated the preterm infant enteral feeding knowledge levels and practices of neonatal nurses working in eight different hospitals in Istanbul, a sample which we believe is fairly representative of the Turkish population. The moderate average knowledge level of these nurses (67.12 ± 8.83) revealed ongoing deficits in knowledge about enteral feeding practices among neonatal nurses in Türkiye [24, 25]. In our study, it was determined that neonatal nurses who completed undergraduate or graduate nursing education had higher knowledge scores than nurses whose highest level of education was high school (P = .027; Table 3). This finding is consistent with the literature showing that nurses who receive undergraduate and graduate nursing education have more evidence-based knowledge and reflect it in practice [33]. In addition, older age (P = .001), longer NICU experience (P = .003), and having a neonatal nursing certification (P = .001) were other factors found to positively affect knowledge levels (Table 3), consistent with previous reports [24, 34, 35].

In the literature, it is stated that gravitational delivery of enteral feeds is more suitable for the physiological tolerance of infants compared to bolus feeding [36]. Holding the injector approximately 20 cm above stomach level while feeding is reported to support the passage of food at physiological speed and ensure controlled flow [37, 38]. It has also been emphasized that NG/OG placement may cause pain and physiological stress responses in infants and may become a noxious stimulus for the infant [32, 39, 40]. The majority of neonatal nurses in our study knew that holding the injector approximately 20 cm above the infant’s stomach level for gravity feeding was a practice that supports physiological passage (92% ; item 6) and that catheter insertion may cause pain and stress responses in infants (91.3% ; item 29). Evidence-based clinical standards for the safe and effective enteral feeding of preterm infants include proper catheter selection [15], accurate catheter insertion length measurement [41, 42], reliable confirmation of placement [43, 44], compliance with asepsis principles, and appropriate catheter fixation [8, 14]. It is recommended that the NG/OG catheters used for enteral feeding should be appropriate for infants’ anatomical and physiological characteristics and replaced once a week during clinical care [10, 45]. Catheter size should be determined according to the infant’s weight, with a 4 Fr size selected for infants under 500 g, 5–6 Fr for infants weighing 500–1500 g, and 6–8 Fr for infants over 1500 g [46]. In this study, although most (97.3%) of the neonatal nurses knew the statement “The size of NG/OG catheter is selected in proportion to the infant’s weight” was correct (item 17), 70.4% did not recognize the false statement “For infants weighing < 1000 g, a size 6–8 Fr NG/OG tube is selected” as incorrect (item 3) (Table 2). These findings suggest that the nurses have not achieved holistic synthesis of their knowledge and practices in regards to catheter size selection as per current guidelines, and require more information about evidence-based practices in catheter selection for extremely-low-birth-weight preterm infants.

In the literature, it is emphasized that positioning the infant in a supine, neutral position before inserting the catheter [45] facilitates accurate insertion length measurement and increases respiratory safety [41, 42]. Authors have reported that the NEMU method is more anatomically accurate for determining catheter insertion length [47], whereas the NEX method may increase the risk of aspiration because it does not account for individual differences in abdominal anatomy or midline position [42, 47]. In our study, the majority of the nurses (80.3%) did not recognize the incorrectness of the statement “When placing the NG/OG catheter, the patient’s head is elevated 30–45 degrees” (item 4; Table 2) and 58.3% preferred the NEX measurement method to determine catheter length (Table 1), demonstrating that neonatal nurses need more information about these two basic clinical practices. Similarly, Jabbar and AL-Mosawi (2022) reported that nurses had moderate to low knowledge and skill levels in catheter placement practices, with low practical competence, especially in critical steps affecting the accuracy of anatomic measurement [48].

According to the literature, correct NG/OG catheter placement should be reconfirmed before each feeding or drug administration, after position changes, and when the catheter length is changed [8, 14]. Radiography (X-ray) is accepted as the gold standard method for this evaluation. In clinical practice, however, pH measurement is the recommended verification method due to its rapid applicability and reliability [8, 45, 49]. We observed in this study that most of the nurses did not know when catheter placement should be evaluated (item 10; 70.4% incorrect) or the evidence-based methods used to verify catheter placement (item 33; 66.3% incorrect) (Table 2). In addition, the fact that 73.7% of the nurses accepted auscultation as a valid verification method (73.7% ; item 12) indicates that this practice is still widely adopted in clinical practice despite not being recommended in current guidelines. These findings support those of similar studies in the literature [25, 29, 44, 49] showing that nurses cannot adequately integrate evidence-based methods into the clinical decision-making process when it comes to their catheter placement verification practices.

In our study, 52.3% of the nurses agreed with the false statement “The injector used for feeding and checking residuals is washed after each use and changed daily” (item 24; Table 2). In an observational study by Güneş and Çetinkaya (2023), 31.8% of the nurses used injectors without changing them [25]. This rate was found to be lower compared to our study, which might be attributable to the data collection method. These findings indicate that aseptic practices in enteral feeding do not reach the standard level of care in clinical settings. In addition, 63.7% of the nurses incorrectly agreed with the statement “In patients with an NG/OG catheter, the catheter is rotated on its axis 3–4 times a day to prevent the catheter from adhering to the gastrointestinal tract” (item 11; Table 2). This practice is reported in the literature to potentially cause tissue irritation and mucosal damage, and catheter rotation once a day is recommended [15, 27, 50].

Considering the physiological limits of gastrointestinal flow in preterm infants, the recommended flow rate for enteral feeds is 2 mL per minute [10, 25]. However, 88.0% of the nurses incorrectly agreed to a statement about calculating the flow rate as 3–4 mL per minute (item 8; Table 2). This finding reveals that nurses have low awareness of the physiological tolerance limits for enteral feeding infusion rates and the potential complications of administering enteral feeds too fast.

Over half (52.7%) of the nurses in our study stated that the frequency of NG/OG catheter changes was not affected by the lying position of the infant (item 15; Table 2). This indicates that nurses have insufficient clinical awareness of the possible effects of the lying position on enteral catheter management. In the literature, it has been reported that for infants in prone position, OG catheters are changed more frequently, and position changes may play a decisive role in catheter stability and dwelling time [51]. In this context, in terms of increasing the quality of clinical care, it is important for nurses to develop individualized approaches in the planning of catheter care practices by anticipating the risks of position-related complications.

According to current evidence-based guidelines, the basic approach for safe and effective management of the enteral feeding process is gradually increasing the volume of preterm infants’ enteral feeds according to their physiological responses and evaluating gastric residuals only in the presence of clinical indications, taking into account not only the volume but also the color and consistency of the gastric contents [8, 10]. Consistent with the literature, we observed that 95.3% of the nurses in our study correctly agreed with the statement about checking residuals in the presence of abdominal distension or increased abdominal circumference (item 40) and 92.3% knew that the amount of food should be increased as the infant tolerated (item 7). However, it was determined that more than half of the nurses did not respond correctly to the statements “Routine gastric residual checks are performed before each feeding via the NG/OG catheter” (item 20; 51%) and “Gastric residual that is green should always be discarded” (item 27; 70%) (Table 2). These findings showed that neonatal nurses’ enteral feeding management is still not entirely consistent with clinical guidelines.

The fact that the study was conducted in only eight hospitals in Istanbul limits the generalizability of the findings to all neonatal nurses, and the use of self-report measures in data collection may limit the objectivity of the findings. However, even though nurses’ skills were not directly observed in practice, we believed that the nurses would give more accurate information about their practices because their responses were anonymous. In the future, it is recommended to conduct international comparative studies with larger samples and plan prospective, randomized studies.

Conclusion

The results of this study showed that neonatal nurses had a moderate level of knowledge about enteral feeding in preterm infants (mean score 67.12 ± 8.83). Older age (p = .001), longer NICU experience (p = .003), higher education level (p = .043), and NICU nursing certification (p = .001) were associated with higher knowledge levels. We determined that neonatal nurses need more information about catheter size selection in preterm infants with extremely low birth weight, infant positioning during catheter placement and feeding, the necessity of verifying catheter placement before each feeding, the method by which to confirm correct catheter placement, catheter measurement method, recommended flow rates, gastric residual checks, and maintenance of asepsis.

Implications for clinical practice

Determining neonatal nurses’ knowledge regarding the enteral feeding of preterm infants an important step toward ensuring best practice. The findings of this study highlight several critical areas where neonatal nurses need to strengthen their competencies to optimize the safety and effectiveness of neonatal enteral feeding. The nurses in our sample showed moderate knowledge overall, with deficient knowledge specific to catheter size selection for very-low-birth-weight infants, infant positioning during catheter insertion and feeding, verification of catheter placement before each feeding, methods of verifying correct catheter placement, recommended flow rates, gastric residual assessment, and asepsis practices. These knowledge gaps highlight the need for targeted educational and clinical support.

To address these needs, it is crucial to develop and integrate evidence-based, standardized training programs into routine NICU practice. These programs should emphasize the standardization of catheter placement procedures, the use of validated methods for confirming catheter placement, and adherence to enteral feeding protocols consistent with current national and international guidelines. Supporting continuing professional development with certification and quality improvement initiatives will enhance the standardization of enteral feeding practices, contribute to the reduction of feeding-related complications, and improve the quality of care associated with enteral feeding in preterm infants. Future studies should investigate the efficacy of various educational interventions in enhancing neonatal nurses’ knowledge and clinical practices in this area.

Author contributions

Conceptualization: Gözen D., Aykanat Girgin B. Formal analysis: Gözen D., Aykanat Girgin B. Project administration: Gözen D., Aykanat Girgin B. Methodology: Gözen D., Aykanat Girgin B., Çarıkçı F. Investigation: Gözen D., Aykanat Girgin B., Çarıkçı F. Resources: Gözen D., Aykanat Girgin B., Çarıkçı F., Temizsoy E. Data collection: Aykanat Girgin B., Çarıkçı F., Temizsoy E. Visualization: Aykanat Girgin B., Çarıkçı F. Writing-original draft: Gözen D., Aykanat Girgin B., Çarıkçı F. Writing-review & editing: Gözen D., Aykanat Girgin B., Çarıkçı F., Temizsoy E. Supervision: Gözen D., Aykanat Girgin B.

Funding

Not applicable.

Data availability

Data and materials can be accessed through the corresponding authors.

Declarations

Ethics approval and consent to participate

This study has been approved by the Ethics Committee of Health Sciences University in Istanbul, Türkiye (Ethical Review Number: 224.364.IRB3.151). The consent that was obtained from all of the participants was informed. This study was conducted in accordance with the principles outlined in the Declaration of Helsinki.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.