Application of clean intermittent catheterization for neurogenic bladder in infants less than 1 year old

1 Introduction

Neurogenic bladder (NB) is a common pediatric urological disease caused by a variety of neurological pathologies, such as spina bifida, sacral dysplasia, tethered cord, and spinal cord injury, that are difficult to cure (Liao, 2015). Normal voiding is achieved by a voluntary, continuous detrusor contraction that leads to complete emptying of the bladder within an acceptable time span. However, the main pathophysiological basis of NB includes detrusor underactivity, resulting in increased bladder post-voiding residual (PVR) volume and filling pressure. Consequently, vesicoureteral reflux (VUR) and renal damage might occur. Many patients are treated irregularly, which causes renal dysfunction (Sturm & Cheng, 2016). Up to one-third of children with NB have VUR (Sidi, Peng, & Gonzalez, 1986). Therefore, emptying the bladder in time is especially important for children with NB, because it can prevent VUR, urinary tract infection (UTI) and renal damage.

In 1947, Guttmann et al. (1947) reported that sterile intermittent catheterization could be applied in patients with spinal cord injuries to empty the bladder and decrease the risk of UTI. Lapides et al. (1974) introduced clean intermittent catheterization (CIC), which kept intermittent catheterization clean and would not increase the risk of UTI compared to sterile intermittent catheterization because they believed that UTIs were caused by bladder overexpansion leading to decreased bladder blood flow. Later, Lapides published more papers, proposing that the frequency of catheterization was more important than sterilization. Since 1971, CIC has been widespread use as a method to empty the bladder (Frimberger, Cheng, & Kropp, 2012). CIC is now recommended by the International Continence Society (ICS) as the first choice to treat NB with bladder retention because it can effectively reduce PVR, decrease UTIs, prevent or alleviate VUR, preserve renal function and improve the quality of life (Abrams et al., 2003). Although CIC is the standard procedure to treat NB, few studies have been performed to observe the long-term results of patients, especially infants, with NB (Frimberger et al., 2012; Newman & Willson, 2011).

Furthermore, when to begin CIC use in infants and children is still controversial (Kryger, 2008). CIC has been generally used in older children but rarely in infants. Most infants with NB are diagnosed early in life, but the fear of increased numbers of UTIs and urethral injury leads to the avoidance of early CIC in infants. Controversially, Di (2011) believed that older children or adults are more likely to accept this therapy due to their more developed cognitive abilities.

Kryger (2008) recommended CIC use as soon as NB with increased PVR volume is diagnosed. Guerra et al. (2014) believed that parents and children have longer periods to adapt when CIC is used in infancy because it maintains moderate bladder wall thickness and increases bladder compliance. Kochakarn et al. (2004) evaluated the long-term results of early CIC application and noted that upper urinary tract complications were decreased and renal function was improved in patients with NB. However, the urodynamic parameters of these cases were not recorded, resulting in a lack of an objective bladder function assessment. Therefore, to further study the improvement or conservation of bladder function by early CIC, recording the bladder urodynamic parameters is necessary to identify the long-term treatment response. The aim of the present study is to determine whether it is more beneficial to apply CIC when infants with NB are less than 1 year old or are older than 3 years old by assessing the treatment response with regard to bladder function evaluated by urodynamics, renal function, and related urinary tract complications.

2 Methods

3 Results

The BC, SBC and MCC in the ECG were significantly higher than those in the LCG at 3 and 6 years of follow-up (Table 1). At 3 years of follow-up, increased BUN or serum creatinine levels were observed in 1 patients (2.5%) in the ECG and 7 patients (19.4%) in the LCG, resulting in a significant difference between the two groups (P <  0.05). Six patients (15.0%) in the ECG and 14 patients (38.9%) in the LCG had UTIs at 3 years of follow-up, resulting in a significant difference between the two groups (P <  0.05). At 6 years of follow-up, 2 patients (5.0%) with increased BUN or serum creatinine levels in the ECG and 9 patients (25.0%) in the LCG were identified, resulting in a significant difference between the two groups (P <  0.05). UTIs were found in 10 patients (25.0%) in the ECG and 19 patients (52.8%) in the LCG, resulting a significant difference between the two groups (P <  0.05) (Table 2). At 6 years of follow-up in the ECG, the grade I reflux that was observed in 6 patients (15%) was resolved; 28 patients (70.0%) remained stable (27 with no reflux and 1 with grade I); 1 patient (2.5%) with grade II decreased to grade I; and reflux in 4 patients (10.0%) was aggravated (3 with no reflux and 1 with grade I). In the LCG, resolution of reflux occurred in one grade I case (2.8%); 21 patients (58.3%) remained unchanged (20 with no reflux and 1 with grade I); and reflux was exacerbated in 14 patients (38.9%) (11 with no reflux and 3 with grade I) (Tables 2, 3).

CIC has been the preferred method recommended by the ICS to empty bladder (Seth, Haslam, & Panicker, 2014). Joseph et al. (1989) reported that infants less than 1 year old could undergo CIC with good effects. Parents can help infants perform CIC after training.

The literature is limited regarding the long-term follow-up of early CIC in NB patients less than 1 year old. Joseph et al. (1989) found that 89% of patients had a stable upper urinary tract, 42% of patients had bacteriuria, no patients had been hospitalized because of UTI, and no further complications were identified after examining 38 patients with long-term CIC use. Guys et al. (2011) noted that children with NB initiate catheterization without age restriction. Recently, Larijani et al. (2013) highlighted that all infants with NB should undergo catheterization in principle to maintain safe bladder pressure. Wu et al. (1997) compared the effect in 98 patients of different ages without upper urinary tract dilatation after CIC application; they found that, after CIC, fewer young children required cystoplasty than older children. Early catheterization reduced the risk of irreversible harm to the bladder. Most of these studies discussed the effect of early and late catheterization on upper urinary tract complications and kidney function but lacked follow-up regarding urodynamic parameters and bladder function. In the present study, urodynamic parameters, bladder function, urinary tract complications and kidney function were all followed up and analyzed. This study demonstrated that urodynamic parameters, including BC, SBC, and MCC, in the ECG were significantly better than those in the LCG at 3 years of follow-up, indicating that bladder function exhibits a good response to CIC. At 6 years of follow-up, the three urodynamic parameters were also significantly better in the ECG than those in the LCG, showing that bladder function is improved if CIC is used before the age of 1 year. Although bladder function is still decreased compared to normal children, early CIC application can obviously reduce the gap and improve bladder function.

Edelstein et al. (1995) compared the effects between early and late treatment in patients with upper urinary tract dilatation and found that 80% of the patients in the late treatment group had progressive renal injury, whereas only 15% had kidney damage in the early treatment group. Their studies lacked patients with a normal upper urinary tract. We chose both normal upper urinary tract and VUR patients to follow up and to record their bladder and renal functions. The study suggested that more children had VUR in the LCG than that in the ECG at 3 years of follow-up; the numbers of patients with increased BUN or serum creatinine levels were significantly different between the two groups. At 6 years of follow-up, the numbers of patients with VUR, increased BUN or serum creatinine levels in the ECG were obviously lower than those in the LCG. The bladders of children in the LCG had a high-pressure status for a long time, leading to ischemia of the bladder wall and fibrosis of the bladder, causing decreases in BC and damage to the bladder contraction function. However, children in the ECG could empty their bladders in time to protect bladder function and prevent upper urinary tract damage. However, some of the early CIC patients also had elevated VUR, BUN or serum creatinine levels as a result of a long catheterization interval that caused high bladder filling pressure. Mcguire et al. (1981, 1983) suggested that persistent intravesical filling pressures of more than 40 cmH₂O are damaging the upper urinary tract. Consequently, the catheterization time interval is critical for the effect of CIC. The catheterization interval was determined according to the safe bladder pressure and residual urine volume. CIC needs to be performed before bladder filling pressure exceeds 40 cmH₂O to minimize the risk of upper urinary damage. The liquid intake of children with NB will directly affect urine volume and catheterization times. Therefore, an appropriate amount and regular water intake is particularly important for the results of CIC. Furthermore, patients can adjust the catheterization time according to the catheterization volume (Nazarko, 2012). If the frequency of catheterization is too high and the interval time is short, excessive bladder filling is avoided, but the patient’s inconvenience and risk of the urinary tract injury will be increased. However, if the amount of catheterization is not sufficient, the risk of UTI is elevated as a result of the increasing residual urine volume.

The most common complication of CIC is UTI, which will exhibit increased incidence due to destruction of the delicate urethra of infants (Chaudhry et al., 2017; Forster, Haslam, Jackson, & Goldstein, 2017; Wyndaele et al., 2012). In addition, the presence of residual urine or VUR in children with NB may also contribute to UTI. Kochakarn et al. (2004) compared the long-term results between an early CIC group (<3 years old) and a late CIC group (>3 years old). They found no significant difference regarding UTIs between the two groups. Joseph et al. (1989) believed that bacteriuria was frequently present but easy to cure and did not cause sequela in CIC of infants. This research showed that the incidence of UTI in the ECG was significantly lower than that in the LCG at 3 and 6 years of follow-up, indicating that early application of CIC reduces the incidence of UTI as a result of decreasing PVR volume and upper urinary tract complications.

5 Conclusion

In summary, we believe that CIC is an appropriate alternative for children with NB who need to empty their bladders within a specific time. Furthermore, early CIC greatly improved bladder function and prevented UTI and upper urinary tract function impairment in infants with NB who were less than 1 year old. At the same time, the incidence of UTI decreased with the early application of CIC. However, further research with a larger number of cases and with longer follow-up is needed to investigate the effect of early CIC. Unfortunately, insufficient attention has been focused on increasing the use of CIC in China. We advocate that children with NB who meet the CIC criteria should be recommended to utilize CIC as soon as possible, especially in the first year of life, to improve their quality of life and lighten the burden on the family.

Conflict of interest

The authors declare no conflict of interest.