Audit Article

An analysis of urinary tract trauma in Scotland: Impact

on management and resource needs

S. V. Bariol¹ G. D. Stewart¹ R. D. Smith² D. W. McKeown D. A. Tolley¹

¹The Scottish Lithotriptor Centre, Western General Hospital, Edinburgh, Scotland

²Scottish Trauma Group, Royal Infirmary of Edinburgh, Scotland

Correspondence to: S. V. Bariol The Scottish Lithotriptor Centre, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, Scotland

Introduction Patients and Methods Results Discussion Conclusion References

Objective: We report the incidence, distribution, aetiology and outcome of urological trauma in a unique national database to provide an insight into its contemporary management. Patients and Methods: The Scottish Trauma Audit Group prospectively collected data from severe trauma presenting to all major Scottish hospitals. We examined data from 24,666 trauma admissions from 1999 to 2002. Patients who sustained urological injuries were identified and studied in detail. Results: 362 patients had urological injuries, comprising 1.5% of the trauma population, and an incidence of 1 per 45,000 head of adult population per year. Blunt injury (n =285, 79%) was the main cause of urological trauma. Road traffic accidents were most frequent (197 patients, 54%), followed by assaults (76, 21%) and high falls (45, 12%). Renal injuries were the most common (n=241, 67%), followed by injuries to the external genitalia (71, 20%), bladder (65, 18%), urethra (16, 4%) and ureter (3, 1%). Only 52 patients (14%) had isolated urological trauma. One hundred and fifty nine out of 310 (51%) urological patients with associated injuries were physiologically compromised on arrival in A&E, compared with only 4/52 (8%) patients with isolated urological trauma. All patients with isolated urological trauma survived, whereas 110/310 (35%) of those with associated injuries died. Conclusion: Urological injuries in Scotland mostly result from blunt trauma due to high-energy impacts. Isolated urological injuries are uncommon and all such patients survived. The majority of patients with urological trauma have multiple injuries and require a multi-disciplinary approach. Current urological services appear adequately distributed to cope with contemporary demands of urological trauma

Keywords: trauma, urogenital Surgeon, 1 February 2005, 22-25

INTRODUCTION

Trauma is the leading cause of death in men and women under the age of 40 in the United Kingdom.¹ The Scottish Trauma Audit Group (STAG) was established in 1991 to observe and improve the management of severely injured patients. Genitourinary injuries are responsible for up to 10% of trauma admissions in the United States.² The incidence of genitourinary trauma in the United Kingdom has not been described but given the substantially different mechanisms of trauma in the two countries, injury patterns are likely to differ.³ Major genitourinary trauma is perceived as occurring infrequently and being conducive to non-operative management in the majority of cases.

^4,5 Further study of the incidence, severity and management of urological trauma in the United Kingdom is necessary to ensure allocation of appropriate resources, particularly in the context of proposed changes to training.

PATIENTS AND METHODS

The Scottish Trauma Audit Group prospectively collected data from patients with severe trauma presenting to all major Scottish hospitals over four years (1999-2002), being the interval with the highest national data capture rate (95%). Information was collected on injured patients who were admitted for at least three days or who died in hospital. All children aged less than 13 years, as well as patients over 65-years-old with isolated fractured neck of femur or pubic ramus, were excluded from the audit. Trauma patients who arrived in the emergency department in cardiorespiratory arrest were excluded unless their period of attempted resuscitation in the department exceeded 15 minutes.

The data collected included patient demographics, type and mechanism of injury, presentation physiology, investigations, procedures and outcome. All injuries were recorded and scored according to the Abbreviated Injury Scale (AIS).^6-7 The Abbreviated Injury Scale allocates a code to each specific injury and a score from one to six that increases with injury severity (e.g. minor renal contusion, AIS score=2; major renal laceration, AIS score=4). The AIS score corresponds with the American Association for the Surgery of Trauma (AAST) staging system for renal injuries, with which most urologists are familiar.8 This allowed a standardised measure of the overall extent of the patient’s injuries to be calculated, the Injury Severity Score (ISS).9 The ISS is derived from the three highest individual AIS scores in different body regions. A higher ISS occurs in patients with multiple severe injuries, and is associated with a higher mortality.

The audit also measured each patient’s Revised Trauma Score (RTS) on presentation to the Accident and Emergency (A&E) department. The RTS is a physiological score derived from a patient’s Glasgow coma scale (GCS), systolic blood pressure (BP) and respiratory rate (RR).¹⁰ Patients have abnormal RTS if they have a GCS<13, systolic BP < 90 or a RR < 10 or > 30.

Those patients who sustained urological injuries were identified from the database to analyse specific aspects of their care pertaining to urological intervention and outcome. Patients were regarded as having “isolated” urinary tract trauma if they had avoided injury in another body region, or those injuries were minor (AIS score=1). The remaining patients had more serious (AIS score =2+) associated injuries in other body regions.

We compared proportions using Fisher Exact probability tests. The influence of renal and bladder AIS scores on patient outcome was examined in logistic regression models. SPSS V11.0 was used throughout.

RESULTS

There were 362 patients, 1.5% of the trauma database (n=24,666) for study, who had sustained urological injuries. The incidence of urinary tract trauma amongst the adult Scottish population, therefore, was one case per 45,000 people per year based on 2001 population figures.¹¹ The majority of injuries were grade 2 or less (Table 1). Genitourinary injuries occurred in 22% of all patients admitted with abdominal trauma (n=1680). Blunt injury was the cause in 285 patients (79%) and penetrating injuries in 77 patients. Assaults were responsible for 68 (88%) of penetrating injuries, however, road traffic accident was the most common mechanism of injury overall (197, 54%). Analysis of urological trauma cases by hospital revealed that consultant urology cover was available for 302 (83%) of the patients, including 198 (66%) supervising a urology specialist registrar.

Renal injuries were the most common (n=241, 67% of patients), followed by injuries to bladder (65, 18%), external genitalia (63, 17%), urethra (16, 4%) and ureter (3, 1%). 

Fifty-two patients (14%) had “isolated” urinary tract trauma, including 32 with minor (AIS score=1) associated injuries. Twelve (23%) of these patients had laparotomies, whilst a further eight had other minor operative procedures.

One hundred and eighty four (59%) of the 310 patients who had associated injuries had abdominal injuries (Table 2). One hundred and ninety four (63%) of the patients with associated injuries required operative management; 90 (46%) of these were laparotomies.

Few patients with isolated urological trauma were physiologically compromised on arrival in A&E. In comparison, half of patients who had associated injuries were also physiologically deranged (Table 3, p<0.001). Mortality increased with the ISS (Table 4). One hundred and ten cases out of 310 (35%) of those with associated injuries died (p<0.001), including 45% of multi-injured patients with renal trauma and 38% of those with bladder trauma. Amongst multiply-injured patients with renal or bladder injuries, there was no significant increase in mortality with the severity of the renal or bladder injury per se (Table 5; logistic regression: renal, p=0.08, bladder, p=0.08). All 52 patients with isolated urinary tract trauma survived. Amongst patients with serious overall injuries (ISS 16-75) survival rates did not differ significantly between teaching hospitals and district general hospitals (49/95 [52%] survived, versus 85/148 [57%] P=0.43).

DISCUSSION

The Scottish Trauma Audit Group was set up to observe and improve all aspects of trauma management, including pre-hospital care, A&E services and inpatient management.¹² Optimal use of this audit requires collaboration with all specialties involved in trauma care in order to generate national standards of care. The national capture rate of 95% is impressive. Trauma registries have been used extensively to evaluate trauma management and outcome and are superior to administrative databases, which are prone to reporting errors of diagnosis, therapeutic intervention and survival.¹³

The total number of admissions with urological trauma in the STAG database is likely to be an underestimate of all urological admissions given that the majority of patients with isolated minor urological injuries will have an admission of less than three days. Thus, our data may underestimate the true impact of isolated urological trauma but minor injuries are unlikely to be significant in terms of morbidity or use of resources. Patients with multiple injuries, or moderate to severe urological trauma are more likely to have a longer admission and, therefore, will be included in the population studied. The latter group exhibits significant morbidity and comprises the greatest burden on urological services. Therefore, the results presented in this article reflect accurately patients with significant urological trauma in Scotland who require early and specialist urological assessment.

Few patients with isolated urological trauma were physiologically compromised on presentation, compared with more than half of patients with associated injuries. If a patient with urological injury is physiologically deranged, it is likely that they have multiple injuries.

Bladder and renal trauma in association with other injuries and higher ISS is associated with significant mortality. However, there appears to be no relationship between the severity of the urological injury alone and outcome in these patients, a finding previously reported.^14,15 In addition, there were no deaths among those patients with isolated urinary tract injury in this study. It follows that the patient with multiple injuries requires a multidisciplinary approach, preferably led by a surgeon experienced in trauma care.^14,16 Apart from military surgical personnel, the establishment of specialty trauma surgeons appears unlikely given the rarity of penetrating trauma in the United Kingdom.³ Nevertheless, the management of renal and bladder trauma by general surgeons has previously been shown to be safe and does not affect the complication or nephrectomy rates.⁵ Although all patients with isolated urological trauma survived in this series, there is the potential for morbidity should urological management be delayed.^17-19 The relatively low frequency of genitourinary injuries and, in particular, severe injuries, demonstrated in this article would suggest that current urological services meet the required demand. The distribution of urological services, within the context of Scotland’s unique geography and large number of remote communities, also appears to be appropriate given the high percentage of consultant cover available to trauma admissions. The effect of proposed restructuring of urological training with introduction of a new grade (urologist and urological surgeon) is difficult to predict, and governing bodies need to determine whether this intermediate grade will be adequately trained to manage trauma. Once again, the low frequency of urological trauma we have demonstrated implies 

that experience with these injuries is difficult to obtain, especially in a shorter time period. We have demonstrated that those hospitals with urology trainees treat a slightly higher proportion of trauma patients and current guidelines concerning trainee allocation should ensure that sufficient exposure to trauma management is achieved.

CONCLUSION

Knowledge of the epidemiology and outcome of trauma has major implications for the planning of urological services, as well as identification of those centres that can provide appropriate training. The incidence of associated trauma and their potential morbidity demands a multi-disciplinary approach to most patients attending with urological trauma.

ACKNOWLEDGEMENTS

We would like to thank Diana Beard RGN MBA, Director of the Scottish Trauma Audit Group, for her support.

Copyright 5 December 2004

REFERENCES

1. ”Accidents” The Health of the Nation. Department of Health, London: HMSO, 1992: 102-15.

2. McAninch JW, Santucci RA.Genitourinary injuries. In: Walsh, Retik, Vaugh, Wein eds, Campbell’s Urology, 8th edn, Vol.IV. Chapt 105. Saunders: Elsevier Science, 2002: 3707.

3. Bain IM, Kirby RM, Cook AL, Oakley PA, Templeton J. Role of the general surgeon in a British trauma centre. Br J Surg 1996; 83:1248-51.

4. Moudouni SM, Patard JJ, Manunta A, Guiraud P, Guille, Lobel B: A conservative approach to major blunt renal lacerations with urinary extravasation and devitalized renal segments. BJU Int 2001; 87:290-94.

5. Hammer CC, Santucci RA. Effect of an institutional policy of nonoperative treatment of grades I to IV renal injuries. J Urol 2003; 169: 1751-53.

6. Committee on Medical Aspects of Automotive Safety, Rating the severity of tissue damage. I. The Abbreviated Injury Scale. JAMA 1971; 215:277-80.

7. The Abbreviated Injury Scale. 1990 Revision. Illinois: Association for the Advancement of Automotive Medicine

8. Moore EE, Shackford SR, Pachter HL, Mcanich JW, Browner BD, Champion HR et al. Organ injury scaling: spleen, liver, and kidney. J Trauma 1989;29:1664-66.

9. Baker SP, O’Neill B, Haddon Jr W, Long WB. The Injury Severity Score: a method for describing patients with multiple injuries and evaluating emergency care. J Trauma 1974; 14:187-96.

10. Boyd CR, Tolson MA, Copes DW. Evaluating trauma care: the TRISS method. Trauma Score and the Injury Severity Scale. J Trauma 1987; 27:370-78.

11. Scotland’s Census - 2001 Population Report. General Register Office for Scotland, 2002.

12. Beard D, Henry JM, Grant PT. National audit of the management of injured patients in 20 Scottish hospitals. Health Bulletin 2000; 58:118-26.

13. Wynn A, Wise M, Wright MJ, Rafaat A, Wang YZ, Steeb G et al. Accuracy of administrative and trauma registry databases. J Trauma 2001; 51:464-68.

14. Hsieh CH, Chen RJ, Fang JF, Lin BC, Hsu YP, Kao JL, et al. Diagnosis and management of bladder injury by trauma surgeons. Am J Surg 2002; 184:143-47.

15. Kuo RL, Eachempati SR, Makhuli MJ, Reed RL 2nd. Factors affecting management and outcome in blunt renal injury. World J Surg 2002; 26:416-19.

16. Routt ML, Simonian PT, Defalco AJ, Miller J, Clarke T. Internal fixation in pelvic fractures and primary repairs of associated genitourinary disruptions: a team approach. J Trauma 1996; 40: 784-90.

17. Dobrowolski ZF, Weglarz W, Jakubik P, Lipczynski W, Dobrowolska B. Treatment of posterior and anterior urethral trauma; BJU Int 2002; 89: 752-54.

18. Asgari MA, Hosseini SY, Safarinejad MR, Samadzadeh B, Bardideh AR. Penile fractures: evaluation, therapeutic approaches and long-term results. J Urol 1996; 155: 148-49.

19. Husmann DA, Gilling PJ, Perry MO, Morris JS, Boone TB. Major renal lacerations with a devitalized fragment following blunt abdominal trauma: a comparison between non-operative (expectant) versus surgical management. J Urol 1993; 150:1774-77.