Hemodynamic Instability associated with pelvic fracture
Fig. 2: Protocol for emergency treatment of complex pelvic fractures
This "module" is part of the standard treatment algorithm applied in every patient suffering from polytrauma situation.
Early Management of polytraumatized patients with pelvic fracture
Unfallchirurgische Klinik der Medizinischen Hochschule Hannover
T. Pohlemann, A. Gänsslen, T. Hüfner, H.Tscherne
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Correspondence to
Introduction
Exsanguination is still the major cause of death after severe pelvic trauma. The term "complex pelvic trauma" is defined as pelvic fracture combined with a concomitant soft tissue lesion in the pelvic region, which represents injuries to the urogenital system, holovisceral injuries, neurovascular injuries and significant damage to the integumentum2. Wheras these injuries only represent about 10 % of all pelvic fractures, this specific group of patients is highligted by a siginificant increase in lethality up to 33% when compared to injuries without concomitant soft tissue damage.
Beside the osteoligamentous injury of the pelvis this peripelvic soft tissue injury is of major importance. Therefore additional defintions have been proved.
Definitions
• "Simple" Pelvic Fractures: This group contains the majority of pelvic fractures (about 90%). with no significant soft tissue injury. Osteoligamentous instability is possible.
• "Complex Pelvic Trauma" is defined as a pelvic fracture combined with a concomitant soft tissue lesion in the pelvic region, which represents injuries to the urogenital system, holovisceral injuries, neurovascular injuries and significant damage to the integumentum2.
• Fractures with "Pelvic and Hemodynamic Instability" are charcterised by an unstable pelvic fracture combined with a hemodynamic instability related to the pelvis. The term "hemodynamic instability" is based on the classification of BONE1 with an estimated overall blood loss of more than 2000 ccl (class III and IV). Due to the difficulty of estimating the amount of blood loss in the emergency situation a hemoglobin concentration of 8g/dl at admission is used.
• "Traumatic Hemipelvectomy" is defined as total or subtotal dislocation of one or both hemipelves with complete disruption of the vascular and nerval structures of the pelvis (i.e. iliac vessels and lumbosacral plexus).
During resucitation unstable pelvic fractures combined with a hemodynamic instability related to the pelvis require special attention. Here the cause of death is early exsanguination or the late sequalae of prolonged shock and mass transfusion. Exspecially large amounts of hematoma and the residual necrotic muscle mass of bleeding induced extrapelvic compartment syndroms are important mediators for development of a sepsis.
Several treatment protocols for emergent hemostasis were published with a wide variety of methods ranging from waiting for self tamponade, MAST suites, spica casts, to angiography and embolisation, early external or internal stabilization and an aggressive open surgical hemostasis.
The longitudinal evaluation in the authors institution showed, that with consequent application of a primary treatment algorithm, including early decision making within 30 minutes after admission, early pelvic stabilization and an aggressive surgical hemostases the lethality of complex pelvic fractures dropped from 46% (1972-1984) to 25% (1985-1993) in a comparable group of patients including age, severity of general trauma and severity of pelvic trauma (Fig. 1).
Fig. 1: Lethality after complex pelvic injuries.
The lethality after "Complex Pelvic Trauma" which represents a pelvic fracture with a significant concomitant soft tissue injury in the pelvic region (integumentum, neurvascular, urogenital and holovisceral) were compared in two periods of time. Starting 1984 a specific interest was drawn into the devlopement of a specific emergency treatment protocol for complex pelvic fractures, in 1989 the Pelvic C-Clamp was introduced. Both groups are camparable in age, severety of general trauma (PTS = Hannover Polytrauma Score) and the severety of pelvic soft tissue trauma (HFS = Hannover Fracture Scale Pelvis2)
Fig. 1
Treatment protocol
A standardized protocol for primary clinical treatment is used for all patients being admitted in "polytrauma" situations. If a significant pelvic fracture is present, this protocol is expanded by a "complex pelvix fracture module" based on three decisions to be made within 30 minutes after admission (Fig. 2).
The first decision is made after 3-5 minutes. In cases of massive pelvic hemorrhage or a pelvic crush injury immediate transport to the operation room is performed. In all other cases a maximum of resucitaion is performed and primary diagnostics are started (i.e. x-ray chest, pelvic and ultrasonography of the abdomen).
After 10 minutes the second decision is made. If the patients general condition is stable further treatment is orientated according to the general polytrauma algorithm. With remaining hemodynamic instability first massive blood replacement (packed red blood cells) in combination with emergency stabilization of the pelvic instability with a pelvic C-clamp is performed. This procedure showed a beneficial effect in reducing the amount of bleeding, but was not completely effective as definitve method for hemostases.
In the cases were hemodynamic stability was not achieved within 10-15 minutes after admission, a surgical revision of the pelvic retroperitoneum is performed. When the origin of bleeding can clearly be focused to the pelvic region, a midline incision of the lower abdomen is used, leaving the peritoneum intact. In the majority of cases all parapelvic fascias are already disrupted. After incision of the skin a large paravesical cavity filled with hematoma and blood clots is usually present. A direct manual access through the right or left paravesical space down to the presacral region is therefor possible without further disection. Primary orientation includes the check for an arterial bleeding which is accessed either by clamping, ligature or a vascular repair. In mass bleeding a transient clamping of the infrarenal part of the aorta can be helpful. In the majority of cases a specific source of bleeding cannot be identified, the origin of hemorrhage is diffuse either from the venous plexus or the fracture site. In external type injuries the sources of bleeding is generally located close to the anterior pelvic ring. In this region control of bleeding by surgical hemostases, closure of the pelvic ring and paravesical packing is relatively easy. With a higher degree of pelvc instability, especially in C-type injuries the origin of bleeding is most frequently located in the prevesical region. With all compartment borders disrupted this space is generally easy to be manually accessed. The praesacral and paravesical region is packed using standard surgical tamponades. An amount of 4-8 swaps will be necessary for sufficiant compression in the small pelvis. When the accute situation is under control, the integrety of the bladder and urethra is inspected. An urological repair should be adaequate to the patients general situation and is generally restricted to suprapubic urine drainage, insertion of a transurethral catheter and suture of the bladder.
The effectiveness of the tamponade is checked again and all now identifiable bleeding is controlled by direct surgical means. If the quality of reduction of the posterior ring is unsatisfactory, it has now to be improved for minimizing bleeding from the fracture site. This is performed by a short loosening of the clamp, manual traction and internal rotation of the leg and control of reduction by direct palpation of the easily accessable posterior pelvic ring. Then the definitive packing is applied and the fascia is closed.
When the abdomen has to be left open an at least partial closure of the extraperitoneal fascia in the pelvic region is recommeded for supporting the tamponade effect. Then the patient is transferred to the intensive care unit for further stabilization.
With persistant bleeding an angiography combined with embolization can now be performed. With still active bleeding and need for blood substitution first the body temperature has to be normalized as soon as possible for stabilization of the intrinsic hemostatic system. With normal body temperature a second attempt for hemorrhage control by changing the packing is performed.
With stabilized hemodynamics the packing is left in place for 24-48 hours. During the "second look" operation the local overview is significantly improved and the bleeding has completely stopped or can be controlled by local surgical hemostases. With a persitent bleeding new tamponades are inserted and a "third look" is planned 24-48 hours later.
Discussion
Hemostasis in complex pelvic fractures is still a major problem in trauma care. Several protocols have been advocated using a wide variety of techniques. Anti schock trousers showed no impact on the survival rate of the patients and due to the extremely short rescue times are not suitable in an european setting. Waiting for "self tamponde" is a passive procedure and for anatomical reasons can not become effective in the severe cases of complex pelvic injuries, as all parapelvic compartments will be ruptured. Angiography and embolization was advocated by various authors, but several studies proved that the incidence of arterial bleeding is only 10-15 % of the cases. So just a small percentage of patients are primarily accessable by this method. This procedure is therefore not recommended as the primary method of choice.
Pelvic stabilization was reported to have a beneficial effect both on the acute patients situation and late outcome3. With the use of the emergency pelvic clamps an effective stabilization of the posterior pelvic ring can now be performed very early during the resucitation phase.
Only a standardized treatment protocol including the time factor will allow undelayed decision making during the early resucitation phase. Personal experience showed, that emergency stabilization of the posterior pelvic ring alone was often not effective for definitive hemostases. In these cases a surgical revison and simple compression by packing at the region were the bleeding is originated - the paravesical and praesacral venous plexus- usually improves the situation. The specific impact of this procedure on the survival rate cannot be validaded by statistical comparison as these patients have a great variety of concomitant injuries and the individual situations including the cause of accident, rescue time, prolonged shock time, body temperature etc., restricts comparison.
The elaboration of a specific ermergency protocol for treatment of unstable pelvic fractures complicated by pelvic related blood loss is therefore recommended for every trauma center treating major trauma4. It has to include the individual medical resources and circumstances. In our specific situation as a Level I trauma center with a majority of cases suffering from high energy blunt trauma tamponade for hemostases of pelvic bleeding showed a beneficial effect when applied as part of the treatment algorithm including rapid resucitation, early stabilization and immediate surgical revision of the pelvis when necessarry.
Bibliography
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2. Bosch, U., Pohlemann, T., Haas, N. and Tscherne, H.: Klassifikation und Management des komplexen Beckentraumas. Unfallchirurg. 95:189, (1992).
3. Pohlemann, T., Kiessling, B., Gänsslen, A., Bosch, U. and Tscherne, H.: Standardisierte Osteosynthesetechniken am Beckenring. Orthopäde. 21:373, (1992).
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