The kidneys are situated on the posterior abdominal wall on either side of the vertebral column, between the twelfth thoracic and third lumbar vertebrae. The right kidney is normally slightly lower than the left due to displacement by the liver. The kidney is approximately 14 cm long, 6 cm wide and 3 cm thick, and weighs between 135 g and 150 g in adults. The adrenal glands are situated immediately above each kidney.

Each kidney is surrounded by a protective capsule made up of fibrous connective tissue, along with an additional layer of perinephric fat; these layers help to cushion and protect the organ against direct trauma. The renal arteries, renal veins, lymphatic supply and the nerves both enter and leave the kidney at the renal hilum, which is recognized as an indentation on the medial, concave border of the kidney. The funnel-shaped upper end of the ureter also enters at the hilum and expands to become the renal pelvis.

Two distinct areas lie beneath the capsule of the kidney: the outer cortex and the inner medulla body making up the renal parenchyma. Within the medulla there are 8–18 wedge-shaped structures evident, called the medullary pyramids. These drain into minor and then major calyces, which are hollow protrusions of the renal pelvis. The calyces distend as the urine collects within them, leading to peristaltic contraction of the smooth muscle in the walls of the calyces and renal pelvis. The urine is then projected forward from the renal pelvis into the ureter.

The bladder lies low in the pelvis, expanding upwards and forwards in the abdominal cavity during filling, and is held in place by strong ligaments. In males, the bladder lies in front of the rectum and the bladder neck surrounds the prostate gland. In females, the bladder lies in front of the vagina and uterus (Richardson, 2007b).

At the base of the bladder is a small triangular area known as the trigone, representing the area between the two ureteric orifices and the internal urethral meatus. This area changes little in size during the filling stage but is highly sensitive to stretch and is the area irritated by the presence of foreign bodies, e.g. indwelling urinary catheters (Fillingham and Douglas, 2004).

The bladder is a smooth, distensible, muscular sac lined with mucosa that stores urine temporarily. It is lined with transitional cell epithelium which acts as a protective barrier and allows a stretch facility as it fills with urine. The second submucosal layer is constructed of connective tissue and is known as the lamina propria. The third layer consists of smooth muscle bundles, known as the detrusor muscle. The detrusor muscle contains both longitudinal and circular fibres, which are thought to be distributed throughout the bladder wall rather than arranged in one layer (Bullock et al, 1994). The detrusor muscle has a unique function, as it facilitates stretch during the filling phase of the bladder with little or no change in internal pressure (Berne and Levy, 1999); there is also a voluntary component in controlling the storage and emptying ability of this muscle. The superior surface of the bladder is covered by the peritoneum when empty, but during the filling phase the peritoneum lifts upwards and backwards and is therefore not a ‘true’ layer of the bladder.

The bladder and the urethra function together as a complex unit for the storage and expulsion of urine. The bladder neck differs in males and females and its role in the maintenance of continence is not clearly understood; however, it might have some impact on maintaining closure pressure while the bladder fills with urine.

The function of the urethra is to convey urine from the bladder to the exterior. The female urethra is approximately 3–5 cm in length and lies anterior to the vagina. The external urethral meatus opens between the clitoris and vaginal orifice. The urethra is lined with transitional epithelium and with squamous epithelium nearer the external meatus. The external sphincter mechanism is made up of musculature within the urethra in conjunction with the levator ani muscle of the pelvic floor; these combined structures are paramount in the mechanical maintenance of urinary continence. The integral urethral muscle maintains urethral closure, and the pelvic floor muscle increases that closure capacity during a raise in intra-abdominal pressure, e.g. on coughing, laughing and jumping. It is important to note that urine is only found in the urethra during micturition, and during the filling phase of the cycle it remains empty and closed.

The male urethra will be discussed in Chapter 19.

The complex process of urine storage and micturition is controlled by the coordinated activity of parasympathetic, sympathetic and somatic nerves, with control by higher centres in the brain (Blandy, 1998).

Simple urinalysis is a non-invasive test using a chemically impregnated strip to measure the urine pH and to detect the presence of blood, glucose, protein, bilirubin, urobilinogen, ketones, leucocytes and nitrites (Beynon and Nicholls, 2004). It is important to use a clean container to collect a fresh specimen of urine for testing, so avoiding contamination of the specimen. The colour, consistency and smell of the urine should also be noted during routine analysis, and the findings documented. Some things to observe for are a cloudy appearance, an offensive or ‘fishy’ smell, blood and possibly mucus-like strands, which may all be indicative of a urinary tract infection.

If a urinary tract infection is suspected, the collection of urine for culture to identify the offending organisms is indicated. Ideally, a specimen should be obtained before antibiotic therapy is commenced. Urine specimens for culture are usually either a midstream specimen of urine (MSU) or a catheter specimen of urine (CSU) and should be collected in a way that avoids contamination of the specimen with new bacteria.

This is the collection of the total volume of urine voided in a 24-hour period and is of value in the diagnosis of a number of renal and urological conditions, e.g. renal calculi/stone disease and impaired renal function. The patient is asked to void, the time is noted and this first specimen is discarded. All urine voided for the next 24 hours is collected in a large specimen container. The patient is asked to void at the end of the 24 hours, and this specimen is included in the collection. Care should be taken not to spill any preservative present in some of the containers, as it may be corrosive.

It is essential that ‘all’ the urine collected in this time frame is kept, as the overall results will be invalid if an incomplete picture is presented. It is important that the nurse and patient have a full understanding of the procedure.

This measures the rate and volume of urine voided in millilitres per second and is an important investigation in the individual with urinary outflow problems (Schafer et al, 2002). Various types of equipment can be used to measure the flow rate, e.g. rotating disc or dipstick, and all entail the individual voiding into the funnel of a monitoring machine.

Preparation of the patient involves:

Ideally, patients should produce a series of three successive flow rates in order for a more accurate assessment (Fillingham and Douglas, 2004).

Blood analysis is an important part of the investigation of the individual requiring surgery for a renal or urological condition. Blood tests commonly performed are shown in Table 18.1.

Evaluation of renal function includes measurement of plasma urea and creatinine. Renal damage may occur before plasma urea and creatinine levels rise; therefore, creatinine clearance (normally 125 mL/min), which closely correlates to the glomerular filtration rate (GFR), is a more reliable indicator of renal function. This is calculated from measurement of urine volume, plasma creatinine and urine creatinine. Twenty four hour urine collection and a blood sample are also required.

Renal biopsy may be undertaken in the assessment of the individual with renal disease. The procedure can be performed under X-ray control, ultrasound or CT scanning, and a local anaesthetic is used to anaesthetize the area down to the kidney capsule. Preparation of the patient involves obtaining informed consent following a full explanation of the procedure.

Blood specimens pre-procedure are obtained for:

In some centres it is advocated that bedrest is maintained for 24 hours following the procedure. Blood pressure and pulse are recorded ½ hourly initially and at reduced intervals thereafter if within the patient’s normal parameters. A good fluid intake should be encouraged following the procedure (if not medically contraindicated) and observations made of urine output, noting any haematuria.

Cystoscopy involves direct visualization of the bladder and urethra and is undertaken in the individual with a urological problem: e.g. haematuria, lower tract obstruction, or follow-up check cystoscopy for bladder cancer. A rigid or flexible cystoscope is used, and the procedure is performed under either a local or general anaesthetic. The bladder is examined and, if abnormal, biopsies are taken for histological examination. Preparation of the patient involves obtaining informed consent following a full explanation of the procedure. The patient is prepared for either a general or local anaesthetic. Following the procedure, patients might experience urethral discomfort and voiding difficulties. The patient is encouraged to drink 2–3 L in 24 hours (unless medically contraindicated), and the urine should be examined for evidence of haematuria. Any pre-existing urinary tract infection is treated with prophylactic antibiotics.

Specific investigations relating to surgical interventions are summarized in Table 18.2.

For many patients this is a very sensitive and often embarrassing subject to discuss, but one very much impacted upon by urological disease. A voiding history should be undertaken, which includes information on patients’ experiences of urinary frequency, urgency, hesitancy, dysuria, nocturia and haematuria. Patients should be asked to describe their urinary stream when voiding: is the stream strong, do they have to strain to void, do they feel empty on completion? Is urinary leakage or urinary incontinence a problem? Many patients find this a disturbing disease symptom and hide their problem from society, family, friends, and even from themselves (Fillingham and Douglas, 2004). Patients often need support, empathy, clear guidance and good clinical advice when tackling this urinary symptom. Signs and symptoms of urinary tract infection also need to be observed for, e.g. pyrexia, dysuria and offensive-smelling urine. Bowel habits/function should also be assessed, as constipation can be a major contributing cause of urinary symptoms.

Sleep is often affected in some patients experiencing urinary tract disease. In the initial assessment it should be established if sleeping is interrupted by the need to void, and, if so, how many times does the patient need to get up at night?

Urological disease and incontinence can have a significant impact on the quality of life of a patient (Morrow, 2008), as it can affect both their physical and psychological needs. Sensitivity is required when exploring this issue, although it is paramount that the nurse addresses and guides the patient through this care activity and does not take the easy route of avoidance. It should be established if the patient is sexually active, as some minor and intermediate urological procedures can have a direct impact on sexual function. Retrograde ejaculation is often experienced following transurethral resection of the prostate gland or bladder neck incision, which could render the patient infertile. There is also the risk of impotence/erectile disorder following surgery to combat both bladder and prostatic cancer. Having a urethral catheter in situ following surgery impacts on sexual function, but also might have a more profound effect on the patient’s personal body image. Sexual function and activity, and the impact of surgical intervention, are topics that the surgical nurse should be able to tackle with all patients in their care (RCN, 2000).