Biochemical predictors for differentiating intraperitoneal and extraperitoneal bladder perforation

Biochemical Predictors for Differentiating Intraperitoneal and Extraperitoneal Bladder Perforation By Arbay

0. Ciftci,

F. Cahit

Tanyel,

Mehmet

E. $enocak,

Ankara,

Purpose:A out whether differentiate intraperitoneal

retrospective clinical study was performed serum biochemistry alterations may the traumatic bladder perforation to or extraperitoneal.

to find serve to be either

Methods: Thirty-two children treated for traumatic bladder perforation between 1970 and 1997, inclusive, formed the study group. Patients were divided into two groups: intraperitoneal bladder perforation (IBP) and extraperitoneal bladder perforation (EBP) groups. The groups were compared with regard to age, sex, mechanism of injury, and hemodynamic parameters (blood pressure, hematocrit) at presentation (each group was further subdivided into two subgroups according to the duration between trauma and presentation as early (duration <24 hours) and late (duration >24 hours) presentation groups). The subgroups were compared with each other with respect to serum concentrations of urea, creatinine, sodium, potassium, and chloride. Resu/ts: There were 21 boys and 11 girls with 8.7 ? 4.9 years. Mechanisms of injury were accidents (75%), falls (19%), and gunshotwounds was no significant difference between the groups with regard to age, sex, mechanism

a mean age of motor vehicle (6%).There IBP and EBP of injury and

B

LADDER INJURY can occur as a result of either blunt or penetrating trauma and presents mainly in two clinical forms as intraperitoneal bladder perforation (IBP) and extraperitoneal bladder perforation (EBP).l Differential diagnosis of IBP and EBP is important because different treatment methods are required for each clinical form. In the presence of clinical findings suggestive of bladder perforation, the differential diagnosis can be established by retrograde cystography. The severity of bladder injury does not often correlate with the clinical findings and this fact causes delay in diagnosis and management, which contributes to increased morbidity and mortality.2 Serum biochemistry alterations have been proposed to be helpful for the diagnosis of bladder perforation.3-5 To the best of our knowledge, no pediatric clinical series concerning this subject have been published. Therefore, we have performed a retrospective study on children to find out whether serum biochemistry alterations may serve to differentiate the traumatic bladder perforation to be either intraperitoneal or extraperitoneal. MATERIALS

AND

METHODS

The records of Hacettepe University Children’s Hospital were evaluated retrospectively. Patients presenting with traumatic bladder &xma/

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Surgery

Vol 34, No 2 (February),

1999: pp 367-369

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hemodynamic parameters at presentation. The biochemical parameters were found to be within normal range in the EBP group, whereas significantly higher levels of creatinine, potassium, and lower level of sodium were noted in IBP group regardless of presentation time. Significantly higher level of serum urea was recorded in a late presentation group of IBP patients. Co~~c/usions:The authors emphasize that patients presenting with IBP are more likely to present with significantly higher levels of creatinine, potassium, and lower level of sodium compared with the patients with EBP regardless of presentation time. Increased level of serum urea concentration is a characteristic of IBP patients with late presentation. Biochemical alterations can be used to differentiate traumatic IBP and EBP in children with subtle physical examination and radiological findings. J Pedjatr Surg 34:367-369, Copyrjght 0 1999 by W.6, Saunders Company.

INDEX lyte.

WORDS:

Bladder

perforation,

urea,

creatinine,

electro-

perforation and treated at our unit between 1970 and 1997. inclusive, formed the study group. Patients who had EBP + IBP, associated injuries (renal or ureteral injury), or antecedent history of renal or other systemic diseases, which may cause adverse effects on renal function or extravasation of urine into the peritoneal cavity were excluded from the study group. Patients were divided into two groups: intraperitoneal bladder perforation (IBP) and extraperitoneal bladder perforation (EBP) groups. The groups were compared with regard to age, sex, mechanism of injury, and hemodynamic parameters (blood pressure, hematocrit) at presentation. Diagnostic modalities, treatment, and outcome also were reviewed. After confirming the similarity of the groups with regard to the above-mentioned parameters, each group was further subdivided into two subgroups according to the duration between trauma and presentation as early (duration <24 hours) or late (duration >24 hours) presentation group. The subgroups were compared with each other with respect to serum concentrations of urea, creatinine, sodium, potassium, and chloride. When appropriate, data were recorded as mean !c SD, Student’s t test for paired and unpaired samples was used for statistical analysis and P value less than .05 was considered to be significant.

From the Department of Pediatric Surgery, Hacettepe lJniversi@ Medical Faculty, Ankara, Turkey, Presented at the 45th Annuul International Congress of the British Association of Paediatric Surgeons, Bristol, England, July 21.24, 1998 Address reprint requests to Arbay 0. Ciftci, MD, Associate Professor of Pediutric Surgery, Hacettepe University Medical Faculty, 06100, Ankara, Turkey. Copyright 0 1999 by WB. Saunders Cornpuny 0022-3468/99/3402-0031$03.00/0 367

368

CIFTCI

Table 1. Patient Group Age

Characteristics IBP h = 181

EBP (I- = 14)

7.6 5 3.1

10.1 2 5.2

12

9 5

W

tomy plus urethral catheterization (n = lo), and primary repair plus urethral catheterization (n = 4) were the surgical procedures performed in EBP group. A dramatic improvement in abnormal biochemistry levels was noted within 24 hours of appropriate surgical or catheter treatment. There were two deaths caused by severe head injury. The surviving patients were discharged with normal biochemistry values. No complications related to the bladder injury were observed in the short or long term (range, 3 to 14 years) follow-up.

Sex Male Female Mechanism Motor Fall

6 of injury vehicle

accident

15 2 I

Gunshot wound Hemodynamic parameters Hematocrit Blood pressure

(mm

Hg)

9 4 I

36.4 5 2.8 llOi70

39 L 3.5 125i75

DISCUSSION

RESULTS

There were 21 boys and 11 girls with a mean age of 8.7 ? 4.9 years (range, 2 to 16 years). Mechanisms of injury were motor vehicle accidents (n = 24), falls (n = 6), and gunshot wounds (n = 2). There was no significant difference between the IBP and EBP groups with regard to age, sex, mechanism of injury, associated injuries and hemodynamic parameters (blood pressure, hematocrit) at presentation (Table l), showing that the groups were comparable. Gross or microscopic hematuria, abdominal or suprapubit tenderness, and inability to urinate were the most prominent clinical features. The diagnosis of bladder perforation was made by retrograde cystography (n = 22), intravenous pyelography (n = 3), retrograde cystography plus intravenous pyelography (n = 5), and laparotomy (n = 2). The biochemical parameters were found to be within normal range in the EBP group, whereas significantly higher levels of creatinine, potassium and lower level of sodium were noted in IBP group regardless of presentation time. Significant difference was noted in the late presentation group of IBP patients in serum urea concentration. There was no significant difference among the groups with regard to semm chloride concentration (Table 2). Treatment methods in IBP group were primary repair plus suprapubic cystostomy (n = 10) and primary repair plus urethral catheterization (n = 8). Suprapubic cystosTable 2. Biochemical

The bladder is an abdominal organ lying just beneath the anterior abdominal wall and more vulnerable to external trauma in children.z Clinical features may not either support or rnle out traumatic bladder injury. Clinical predictors also are not reliable to differentiate IBP from EBP. Children with a perforated bladder may void clear urine comfortably, whereas a simple bladder contusion may result in severe hematuria or urinary retention with a tender lower abdominal mass.1,zDiagnosis of EBP may be difficult because the clinical picture is very similar to that of an uncomplicated fractured pelvis. IBP also may produce little symptoms and signs at initial phase. Additionally, bladder perforation can be missed easily in a child with severe multisystemic injury. Therefore, a high index of suspicion and detailed evaluation of clinical and radiological findings are required to avoid delay in diagnosis and treatment of bladder perforation during childhood. In the absence of clinical findings suggestive of bladder perforation, metabolic aspects of urinary extravasation could be helpful in establishing the diagnosis. The association between profound disturbances in the sernm urea, creatinine, and electrolytes and the presence of urine in the peritoneal cavity has been reported previously.6-8 The metabolic complications of the interaction between urine and peritoneal membrane has been explained on the basis of a feedback, self dialysis system of the intraperitoneal urine through the peritoneal surface in a child presenting with IBP5 Development of serum urea-creatinine disproportion because of higher clearance and Electrolyte

Analysis EBP

IBP Early Presentation

No. Urea

Late Presentation

Early Presentation

8

IO

6

(mmoi/LJ

7.2 2 2.6

Creatinine fpmoi/L) Sodium (mmol/L)

132 L 9.7* 143 ? 5t

24.1 2 4.8* 196.3 2 24.5*

3.5 ? 1.4 31 2 6.4

Potassium fmmol/L) Chloride (mmol/L)

5.2 2 O.lt 101 k 3

130 k 4t 5.6 2 0.2t 98 k 8

142 2 2 3.9 2 0.5 104 2 2

*f< .Ol versus tf < .05 versus

EBP. EBP

ET AL

Late Presentation

8 5.8 2 2.1 58 141 4.1 102

2 2 2 2

13.4 3 0.4 5

BIOCHEMICAL

PREDICTORS

OF BLADDER

PERFORATION

369

rate of urea than creatinine through the peritoneal membrane has been suggested to be the indicator of IBP when associated with hyperchloremic acidosis, abdominal distension, and tendemess.4 Apart from these case reports, the literature consists of some reports of adult series concerning this subject. One of these studies has shown that IBP simulates the serum biochemical features typical of renal failure (hyperkalemia, increased serum urea, and creatinine) when the diagnosis is delayed for more than 24 hours.9 Biochemical abnormalities have been noted in a minority of the patients if they present within the first 24 hours after trauma. In patients with abdominal symptoms, signs of ascites or ileus, hematuria, and abnormal biochemistry profile suggestive of renal failure, IBP should be considered in the differential diagnosis. In another study consisting of both experimental and clinical data, the investigators have concluded that increased serum urea is a presenting laboratory finding and a sensitive index in the detection of patients who have IBI?l” Previously described serum urea-creatinine4 disproportion has not been confirmed in any of the adult series. In contrary to the above-mentioned studies, the role of blood biochemistry and electrolyte disturbances as a diagnostic aid in bladder perforation has been questioned

by some investigators who have shown in adult series that no significant changes occur in serum urea and creatinine levels either in IBP or EBP.‘Jr The current study is the first pediatric clinical series concerning the role of blood biochemistry and electrolyte analysis in the diagnosis of bladder perforation. The data have confirmed that elevated levels of urea, creatinine, potassium, and lower level of sodium have clinical value in the diagnosis of IBP. Although serum creatinine has been suggested to be a poor index of IBP,r”Jz our findings have shown the opposite by showing the elevated levels of creatinine both in the early and late presentation groups of IBP patients. Our data have confirmed for the first time that significant abnormalities in serum creatinine, sodium or potassium levels occur in all patients presenting with IBP regardless of presentation time. Although urea is known to dialyse more rapidly than creatinine through peritoneal membrane, elevated urea levels have not been noticed in the early presentation group of IBP patients in our series. Our data show for the first time that not only serum urea but creatinine, sodium, and potassium alterations also can be used for the distinction between IBP and EBP regardless of presentation time.

REFERENCES 1. Carroll PR, McAnmch m Major bladder trauma: Mechanisms of injury and a unified method of diagnosis and repair. .I Urol 132:254-257, 1984 2. Bodner DR, Selzman AA, Spimak JP: Evaluation and treatment of bladder rupture. Semin Urol 13:62-65, 1995 3. Mansberger AR; Young JD: The value of ammonia levels as an aid in the diagnosis of urinary extravasation. .I Urol94:125-127, 1965 4. Sullivan MJ, Lackner LH, Banowsky LHW Intraperitoneal extravasation of urine: BUN/Serum Creatinine disproportion, JAMA 221:491-492, 1972 5. Wook Ko K, Randolph J, Fellers FX: Peritoneal self-dialysis following traumatic rupture of the bladder. J Urol91:343-346, 1964 6. Lord JM: Foetal ascites. Arch Dis Child 28:398-403, 1953

7. Hershman H, Allen HL: Spontaneous rupture of the normal urinary bladder-Report of one case. Surgery 35:805-808, 1954 8 Thompson IM, Johnson EL, Ross G: The acute abdomen of unrecognized bladder rupture. Arch Surg 90:371-374, 1965 9. Heyns CF, Rimington PD: Intraperitoneal rupture of the bladder causing the biochemical features of renal failure. Br J Urol60:217-222. 1987 10. Shah PM, Kim KH, Ramirez-Schon G, et al: Elevated blood urea nitrogen: An aid to the diagnosis of intraperitoneal rupture of the bladder. J Urol 122:741-743, 1979 11. McConnel JD, Wilkerson MD, Peters PC: Rupture of the bladder. Urol Clin North Am 9:293-296, 1982 12. Mokoena T, Naidu AG: Diagnostic difficulties in patients with a ruptured bladder. Br J Surg 8:69-70, 1995