Deformability properties of timolol-loaded transfersomes based on the extrusion mechanism. Statistical optimization of the process.

The purpose of this work was to analyze the deformability properties of different timolol maleate (TM)-loaded transfersomes by extrusion. This was performed because elastic liposomes may contribute to the elevation of amount and rate of drug permeation through the corneal membrane. This paper describes the optimization of a transfersome formulation by use of Taguchi orthogonal experimental design and two different statistical analysis approaches were utilized. The amount of cholesterol (F1), the amount of edge-activator (F2), the distribution of the drug into the vesicle (F3), the addition of stearylamine (F4) and the type of edge-activator (F5) were selected as causal factors. The deformability index, the phosphorous recovery, the vesicle size, the polydispersity index, the zeta potential and percentage of drug entrapped were fixed as the dependent variables and these responses were evaluated for each formulation. Two different statistical analysis approaches were applied. The better statistical approach was determined by comparing their prediction errors, where regression analysis provided better optimized responses than marginal means. From the study, an optimized formulation of TM-loaded transfersomes was prepared and obtained for the proposed ophthalmic delivery for the treatment of open angle glaucoma. It was found that the lipid to surfactant ratio and type of surfactant are the main key factors for determining the flexibility of the bilayer of transfersomes. From in vitro permeation studies, we can conclude that TM-loaded transfersomes may enhance the corneal transmittance and improve the bioavailability of conventional TM delivery.

Surgical options in colorectal injuries.

Colonic or rectal injuries occur in up to 10% of patients that suffer penetrating or severe blunt abdominal trauma. The majority of colon injuries are diagnosed intraoperatively following a penetrating abdominal injury. Rectal injuries are usually diagnosed preoperatively with a high index of suspicion based upon the wounding missile trajectory. The vast majority of colon injuries can be primarily repaired with a significant trend toward avoiding colostomy whenever possible. Colostomy is increasingly reserved for rectal injuries and destructive colon injuries with extenuating circumstances such as hemodynamic instability and significant associated injuries.

Complementary roles of diagnostic peritoneal lavage and computed tomography in the evaluation of blunt abdominal trauma.

OBJECTIVE: To assess in randomized prospective format sensitivity, laparotomy rate, and cost-effectiveness of using diagnostic peritoneal lavage (DPL) in a complementary role with computed tomography (CT) in the evaluation of blunt abdominal trauma. METHODS: Blunt trauma patients greater than 18 years of age were eligible for entry in the study. The study period was from February 1999 to July 2000 at an urban Level I trauma center. All patients were hemodynamically stable upon study entry and had abdominal tenderness with Glasgow Coma Scale (GCS) scores > 13 or GCS < 14. Patients were randomized to a DPL arm (DPL-CT) versus a CT arm. If randomized to the CT arm, patients underwent abdominal/pelvis CT. If CT was positive for solid organ injury, patients were observed. If free fluid was identified on CT without solid organ injury, patients were explored. If randomized to DPL-CT, patients underwent closed infraumbilical DPL, except pelvic fractures that were done with the open supraumbilical technique. If the DPL result was > 20,000 RBCs/mm3, patients underwent abdominal/pelvis CT. If the CT following DPL was consistent with solid organ injury, patients were observed. If the CT following DPL identified free fluid without solid organ injury and DPL was > 100,000 RBCs/mm3, patients were explored. RESULTS: Two hundred fifty-two patients were entered; 127 patients were randomized to DPL-CT and 125 to CT. Of the 125 patients randomized to CT, 102 (82%) CT scans were negative, 19 (15%) were positive for solid organ injury, and 3 (2%) had free fluid. Three (2%) of the initial negative CT scan patients underwent delayed laparotomy for missed injuries. Of the 127 patients randomized to DPL-CT, 26 (20%) required CT scan, of which 13 (10%) were positive for solid organ injury and 13 (10%) for free fluid. Positive DPL results that were indications for CT ranged from 21,000 to 1 million RBCs/mm3. Eight of the 13 DPL-CT patients with free fluid on CT had DPL results less than 100,000 RBCs/mm3 and did not require laparotomy. There were no known missed injuries in the DPL-CT arm. Seven (6%) laparotomies were performed in the DPL-CT arm and 10 (8%) in the CT arm. The average cost to the patient for abdominal evaluation in the CT arm was 1611 dollars and 650 dollars in the DPL-CT arm. CONCLUSION: Screening DPL with complementary CT has a low nontherapeutic laparotomy rate and is a sensitive and cost-effective method for the evaluation of blunt abdominal trauma.

Abdominal stab wounds: diagnostic peritoneal lavage criteria for emergency room discharge.

OBJECTIVE: To prospectively evaluate a method for management of abdominal stab wounds that allows for immediate emergency room discharge. METHODS: Anterior abdominal stab wound patients were prospectively placed in a study trial during a 48-month period. Consent was obtained for all patients before study entry. Anatomic boundaries for abdominal stab wounds were costal margins, inguinal ligaments, and anterior axillary lines. Hemodynamically stable patients with negative physical examinations were entered in the study and evaluated with closed diagnostic peritoneal lavage (DPL). Patients with DPL results less than 1000 RBCs/mm3 were sent home. Patients with DPL results greater than 1000 RBCs/mm3 (including gross blood) were admitted for observation. Hemodynamically stable patients with evisceration and no abdominal tenderness had the viscera replaced in the emergency room. Eviscerated patients did not undergo DPL and were admitted for observation. Patients that presented with hemodynamic instability or peritonitis were not entered in the study and underwent immediate surgical intervention. RESULTS: Ninety hemodynamically stable patients were entered in the study. Forty-four (49%) patients had DPL < 1000 RBCs/mm3, 34 of which were discharged home. Of the 10 admissions that qualified for discharge, 4 were admitted due to elevated ethanol levels and no family assistance, 3 were admitted to psychiatry, and 3 required other surgical procedures. No patient with DPL < 1000 RBCs/mm3 required laparotomy or had complications associated with their stab wounds. Thirty-eight (42%) patients were observed because DPL counts were greater than 1000 RBCs/mm3. Eight (21%) of these patients developed positive physical examinations that prompted exploratory laparotomy, of which five (63%) were therapeutic. There were no complications associated with delayed laparotomy. Four (4%) patients had DPL results greater than 500 WBCs/mm3, all of which underwent immediate exploratory laparotomy. Four (4%) patients presented with evisceration, one of which underwent therapeutic laparotomy. CONCLUSION: Abdominal stab wound patients that are hemodynamically stable can be safely sent home from the emergency room when DPL counts are less than 1000 RBCs/mm3. Observation of hemodynamically stable patients allows for low laparotomy rates with minimal morbidity.

Shark cartilage as source of antiangiogenic compounds: from basic to clinical research.

The discovery that angiogenesis is a key condition for the growth of a tumor beyond a millimeter or two, brings about a new approach in the treatment of tumors using drugs able to inhibit the formation of new blood vessels. Also, it has been realized that antiangiogenic drugs can be useful in the treatment of other pathological processes, now classified as angiogenesis-dependent diseases. Initially, cartilage was considered as a possible natural source of antiangiogenic compounds due to its known avascular nature. To date, a number of in vitro and in vivo studies have suggested the existence of antiangiogenic and antitumor compounds in bovine and shark cartilage. However, the potential usefulness of shark cartilage in the treatment of cancer and other angiogenesis-dependent diseases have not been totally accepted due to (i) unsatisfactory patient outcome in clinical trials that have used shark cartilage in cancer patients, (ii) the lack of data that correlates bioavailability with pharmacological effects using oral shark cartilage. Thus, the objective of this review is to describe the main basic and clinical investigations reported in the literature, in which the antiangiogenic and/or antitumor properties of shark cartilage or of its extracts were evaluated. Possible explanations for conflicting results are discussed as well.

Laparoscopic ventral hernia repair reduces wound complications.

Postoperative wound complications can be a source of significant morbidity after open ventral hernia repair. By using smaller incisions a laparoscopic approach may decrease this complication. To determine the rate of wound complications after laparoscopic ventral hernia repair prospectively collected data on morbidity in 54 consecutive patients undergoing ventral hernia repair were analyzed. Wound complications were classified as major if there was an open wound or treatment with intravenous antibiotics was required. Minor wound complications consisted of wound erythema or drainage that was treated on an outpatient basis. Eighteen patients underwent open ventral hernia repair. Thirty-six patients underwent attempted laparoscopic repair; five required conversion to an open procedure. Wound complications occurred in 28 and 16 per cent of patients undergoing open and successful laparoscopic repairs, respectively. However, only 3 per cent of patients undergoing laparoscopic repair had a major wound complication as compared with 22 per cent of patients undergoing open herniorrhaphy. Two-thirds of the major wound complications in the attempted laparoscopic group occurred in patients requiring conversion to an open procedure. Laparoscopic ventral hernia repair is a safe and effective alternative to conventional open ventral hernia repair. The main advantage of this minimally invasive approach is a decrease in the rate of major wound complications.

Demonstration of inhibitory effect of oral shark cartilage on basic fibroblast growth factor-induced angiogenesis in the rabbit cornea.

Several angiogenic inhibitors have been obtained from shark cartilage, some of these are currently in clinical trials for assessment of safety and therapeutic efficacy in humans. Still, shark cartilage taken orally is commonly used in alternative and complimentary medicine for various ailments including serious diseases such as cancer. However, only few studies of oral shark cartilage have demonstrated pharmacological effects in experimental animals or patients, to indicate safe doses with sufficient bioavailability. In the present study we demonstrated the antiangiogenic properties of oral shark cartilage in the rabbit cornea model. Slow-release, polymethylmetacrylate pellets containing basic fibroblast growth factor (bFGF) were surgically implanted in the rabbit cornea to stimulate neovascularization scored by stereo microscopy. Powdered shark cartilage (PSC; commercial product) was tested orally along with a water-soluble fraction (WSF) of this cartilage product which was tested by local application. Animals were treated with oral dosages of 100 mg/kg PSC or 200 mg/kg thalidomide as positive control. Pellets containing WSF (50, 100 or 200 microg/pellet) or bFGF-inhibitor pentosan polysulfate were implanted adjacent to the bFGF pellet. Oral shark cartilage inhibited bFGF-induced angiogenesis, as did oral thalidomide, in this in vivo model. WSF and pentosan polysulfate was shown to block neovascularization in the cornea when applied locally. This study demonstrates that in the rabbit, oral shark cartilage appears to produce systemic levels of angiogenesis inhibitors that can exert their effect at the cornea.

Emergent extra-abdominal trauma surgery: is abdominal screening necessary?

OBJECTIVE: To evaluate the necessity of abdominal screening beyond physical examination in awake and alert blunt trauma patients who require emergent extra-abdominal trauma surgery. METHODS: Data from an urban Level I trauma center was reviewed for all blunt trauma patients who underwent extra-abdominal emergency procedures during the period from January 1995 through August 1998. Awake and alert patients (Glasgow Coma Scale [GCS] score > or = 14) with negative abdominal physical examination results who underwent extra-abdominal emergent surgery were entered in the study. All patients entered were older than 14 years of age, hemodynamically stable, and underwent further abdominal evaluation with computed tomographic scan or diagnostic peritoneal lavage after the decision for extra-abdominal surgical intervention. Emergent surgery occurred within 8 hours of admission. Data was collected for results of diagnostic studies, hemodynamic status, mechanism of injury, indications for operative intervention, and admission blood ethanol (EtOH) levels. RESULTS: A total of 210 patients with an average age of 33 years (range, 14-92 years) were entered in the study. The most common mechanism of injury was motor vehicle crash (67%). Sixty-six (32%) patients presented with EtOH levels > 100 mg/dL; 181 (86%) patients presented with a GCS score of 15, and 29 (14%) presented with a GCS score of 14. The majority of surgical procedures were orthopedic (86%). Diagnostic peritoneal lavage was performed in 55 (26%) patients, and computed tomographic scans were obtained in 155 (74%) patients. Three (1.4%) intraperitoneal injuries were diagnosed in the study population. Two of the injuries were stable grade 1 liver injuries, and missed diaphragmatic injury was diagnosed on postadmission day 1. CONCLUSION: Before emergent extra-abdominal trauma surgery, abdominal evaluation with physical examination is sufficient to identify surgically significant abdominal injury in the awake and alert blunt trauma patient. Screening with additional studies does not impact patient outcome.

Further evaluation of colostomy in penetrating colon injury.

Our objective was to compare, in a randomized prospective format, complication rates associated with primary repair versus fecal diversion in penetrating colon injury. During a 72-month period, 181 patients with penetrating colon injuries were entered in a randomized prospective study at an urban Level I trauma center. After intraoperative identification of colon injuries, patients were randomized to a primary repair or a diversion group. Randomization was independent of previously identified risk factors, including severity of colon injury, presence of hypotension, blood loss, extent of fecal contamination, and time from injury to operation. Five patients initially entered in the study protocol were removed because they died in the immediate postoperative period (< 24 hours). One hundred seventy-six patients were studied, of which 89 were randomized to primary repair and 87 to diversion. The average age in the diversion group was 26.4 years and it was 28.0 years in the primary repair group (P > 0.05). The average Penetrating Abdominal Trauma Index for the diversion group was 22.3, and it was 23.7 for the primary repair group (P > 0.05). There were 18 (21%) septic related complications in the diversion group and 16 (18%) in the primary repair group (P > .05). With respect to risk factors, complication rates were not higher in one study group versus the other. We conclude that, in the civilian population, all penetrating colon injuries should be managed with primary repair.

Surgical management of renal trauma: is vascular control necessary?

OBJECTIVE: To assess in a randomized prospective manner nephrectomy rate, transfusion rate, blood loss, and time of operation in penetrating renal trauma patients randomized to vascular control or no vascular control before opening Gerota's fascia. METHOD: During a 53-month period from January of 1994 to May of 1998, 56 patients with penetrating renal injuries were entered into a randomized prospective study at an urban Level I trauma center. The patients were randomized to a preliminary vascular control group or no vascular control group. Randomization was performed intraoperatively before opening Gerota's fascia. All renal injuries were identified and diagnosed intraoperatively. Intravenous pyelography was not performed preoperatively. If the patient was randomized to the no control group and significant bleeding ensued after opening of Gerota's fascia, the renal hilum was cross-clamped. All injuries were included regardless of patient age, associated injuries, blood loss, severity of renal injury, or other abdominal organs injured. All injuries that required renorrhaphy or partial nephrectomy underwent drainage with closed Jackson-Pratt drainage. RESULTS: Twenty-nine patients were randomized to the preliminary vascular control group, and 27 patients were randomized to the no vascular control group. The average age in the vascular control group was 25.3 years (SD, 10.9) and 23.4 years (SD, 8.2) in the no control group. The average penetrating abdominal trauma index in the vascular control group was 22.9 (SD, 10.9) and in the no control group 23.7 (SD, 13.7). Nine nephrectomies (31%) were performed in the vascular control group, and eight nephrectomies (30%) were performed in the no vascular control group (p > 0.05). The average operative time for the vascular control group was 127 minutes and for the no control group was 113 minutes (p > 0.05). Eleven patients (38%) required intraoperative blood transfusion in the vascular control group (average, 5.5 U/patient transfused) versus eight patients (30%) in the no vascular control group (average, 5.2 U/patient transfused) (p > 0.05). The average blood loss in the vascular control group was 1.06 liters versus 0.91 liters in the no control (p > 0.05). There was one mortality in the study population. CONCLUSION: Vascular control of the renal hilum before opening Gerota's fascia has no impact on nephrectomy rate, transfusion requirements, or blood loss. Operative time may be increased with the vascular control technique.

Role of clinical examination in screening for blunt cervical spine injury.

BACKGROUND: The purpose of this study was to evaluate the hypothesis that awake and alert blunt trauma patients with Glasgow Coma Scores of 14 or 15 (regardless of blood ethanol level or other injuries sustained) can be effectively evaluated with clinical examination without radiographic evaluation of the cervical spine. STUDY DESIGN: During a 32-month period at an urban Level 1 Trauma Center, 2,176 consecutive blunt trauma patients who presented with Glasgow Coma Scores of 14 or 15 were prospectively evaluated by trauma resident housestaff. Housestaff performed physical examinations of the neck and questioned the patients for the presence of neck pain. Following study form documentation of the cervical neck examination, a lateral cervical spine x-ray was performed. Further studies such as swimmer's view and CAT scan were performed if the lateral x-ray could not completely evaluate C1 to C7. These further studies were considered part of the lateral cervical spine (c-spine) x-ray screen. Attending radiologists performed final x-ray interpretations. RESULTS: The study consisted of 2,176 patients, 33 (1.6%) of whom were diagnosed with cervical spine injury. Of the 33 patients with cervical spine injury, 3 had negative clinical examinations (sensitivity, 91%). Lateral c-spine x-ray screen was negative in 1 of these 3 patients. The 2 patients with negative c-spine clinical examination but positive lateral c-spine x-ray screens were diagnosed with C2 spinous process fracture and C6-C7 body fractures. Thirteen patients with negative lateral c-spine screens (sensitivity, 61%) were diagnosed with cervical spine injury. We evaluated 463 patients with blood ethanol levels greater than 100 mg/dL, and 6 (1.3%) were diagnosed with c-spine injury. No injuries were missed on clinical examination in this subgroup with elevated blood ethanol levels. CONCLUSIONS: 1) Clinical examination of the neck can reliably rule out significant cervical spine injury in the awake and alert blunt trauma patient. Addition of lateral c-spine x-ray does not improve the sensitivity of clinical examination in the diagnosis of significant cervical spine injury. 2) Elevated ethanol level is not a contraindication to the use of clinical examination as the screening tool for cervical spine injury. Level of consciousness, as determined by Glasgow Coma Score, is a more effective criterion to dictate a screening method for cervical spine injury.

The role of angiography in periclavicular penetrating trauma.

Our objective was to evaluate whether physical examination in conjunction with chest X-ray can accurately diagnose the presence of significant vascular injury in penetrating periclavicular trauma. Results from a management protocol for penetrating periclavicular trauma were reviewed for the period January 1992 through December 1996 at an urban Level I trauma center. All patients requiring angiography for periclavicular penetrating trauma with trajectory of the injury falling between the lateral border of the manubrium and the anterior axillary line were entered into the management protocol. All patients underwent anterior-posterior chest radiography on arrival to the trauma center and 6 hours after admission. Tube thoracostomy was placed if clinically indicated on presentation or for X-ray findings. Clinical assessment was performed on all patients, with emphasis placed on the presence of "hard" signs for vascular injury. In addition to accepted hard signs for vascular injury, significant chest tube output (>1000 cc) and chest X-ray findings consistent with significant hemorrhage were also considered hard signs for vascular injury. Assuming hemodynamic stability, all patients with suspected subclavian/axillary arterial injury based on wound trajectory or clinical findings consistent with vascular injury underwent angiography. Forty-six patients were entered into the protocol with 30 left-sided injuries and 16 right sided injuries. The majority of injuries were secondary to gunshot wounds (31), with 14 stab wounds and 1 shotgun injury. Emergency room chest X-ray results revealed 32 negative chest X-rays, 7 pneumothoraces, 2 hemopneumothoraces, 2 hemothoraces, and 3 chest tubes placed before initial chest X-ray. A total of 7 injuries were diagnosed, with 1 missed injury, resulting in a sensitivity of 86 per cent for clinical assessment. The missed injury was a pseudoaneurysm of an axillary artery secondary to a self-inflicted shotgun wound. One mortality occurred in this series, which was a death in the operating room secondary to blood loss from an axillary artery injury. We conclude that clinical assessment can adequately diagnose the presence of surgically significant vascular injury in periclavicular penetrating injuries with trajectories lateral to the manubrium.

The utility of physical examination in proximity penetrating extremity trauma.

This study assessed the efficacy of physical examination as a screening modality for the diagnosis of surgically significant arterial injury in proximity penetrating extremity trauma (PPET). All cases of PPET were assessed and admitted per established protocol over a 30-month period from January 1, 1993, to June 30, 1995. No patients were excluded if other body regions were also injured. Landmarks defining upper extremity injuries were the deltopectoral groove to the wrist and for lower extremities from the inguinal ligament to the ankle. Patients admitted with PPET fell into one of three categories: 1) no hard signs of vascular injury present-admitted for 24-hour observation; 2) presence of at least one hard sign of vascular injury-taken immediately to the operating room; 3) positive sign of arterial injury that requires angiography (i.e., diminished but appreciable pulse by physical examination or doppler, large nonexpanding hematoma, bilateral pulse deficit, no appreciable pulse with unreconstructable trajectory). Four hundred six patients with 489 injured extremities secondary to PPET were admitted over a 30-month period. Sixty-two extremities suffered multiple injuries. Of the extremities injured, 83 per cent were secondary to gunshot wounds, 12 per cent were attributed to stabs/lacerations, and 5 per cent were due to shotgun injuries. Four hundred twenty-one extremities with PPET fell into Group 1. There were four missed injuries (specificity, 99%) in this group (one ulnar artery, one radial artery, one posterior tibial artery, and one anterior tibial artery). Two of these injuries were considered surgically significant. None of the patients suffered limb or functional loss as a consequence of their missed arterial injury. Thirty-nine extremities were entered into Group 2, with two patients found to have no arterial injury. Twenty-nine extremities were placed into Group 3 with 10 (35%) found to have surgically significant injury on angiogram. The overall sensitivity and specificity for physical examination was 92 per cent and 95 per cent, respectively, for surgically significant injury. Physical examination is a highly sensitive and specific screening modality for the identification of surgically significant arterial injury in PPET. Patients who present with diminished, but appreciable, pulses by physical examination or doppler, large nonexpanding hematomas as the only sign, bilateral pulse deficits and nonappreciable pulses with unreconstructable trajectory benefit from further investigation with angiography.

The role of presacral drainage in the management of penetrating rectal injuries.

PURPOSE: To compare in a randomized, prospective manner infectious complication rates associated with presacral drainage versus no drainage in the presence of penetrating rectal injury. METHODS: During a 45-month period, 48 patients with penetrating rectal injuries were entered into a randomized, prospective study at an urban Level I trauma center. The patients were randomized to a presacral drainage group or a nondrainage group. Randomization was performed after detection of the rectal injury. Forty-four injuries were identified by proctoscopy (92%), with the rest detected intraoperatively or by physical examination. All patients with rectal injuries were included regardless of age, associated injuries, time from injury to operation, blood loss, severity of rectal injury, other abdominal organs injured, or hemodynamic stability. Rectal injuries were defined as those injuries to the large bowel distal to the peritoneal reflection. All rectal injuries underwent fecal diversion, and all drainage was accomplished using closed Jackson-Pratt drainage. RESULTS: Forty-eight patients were studied, of whom 25 were randomized to no drainage and 23 were randomized to presacral drainage. The average age for the nondrainage group was 21.9 years, and the average age for the presacral drainage group 26.0 years. The average Penetrating Abdominal Trauma Index score was 34.3 for the nondrainage group and 32.4 for the presacral drainage group. There were two (8%) septic complications (one perirectal and one perivesical abscess) associated with the rectal injuries in the presacral drainage group. The abscesses in the drainage group resolved after computed tomography-guided drainage. There was one (4%) septic complication (rectocutaneous fistula) in the nondrainage group, which was associated with a retained missile fragment. The fistula resolved after bedside percutaneous removal of the missile fragment. CONCLUSION: We conclude that presacral drainage for penetrating rectal injuries has no effect on infectious complications associated with the rectal injuries.

Role of prophylactic antibiotics for tube thoracostomy in chest trauma.

The objective of this study was to evaluate the efficacy of antibiotic prophylaxis in association with tube thoracostomy for chest trauma patients with Injury Severity Scores of 9 or 10. A double-blind randomized clinical trial of patients requiring tube thoracostomy was performed at an urban Level 1 trauma center. All patients included in this series were patients with Injury Severity Scores of 9 or 10 (hemothorax/pneumothorax) who suffered isolated chest trauma secondary to blunt or penetrating trauma. Before chest tube placement, 139 patients (34 blunt trauma, 105 penetrating trauma) were blindly randomized to Group A (71 patients) for which they received 1 g cefazolin intravenously every 8 hours or Group B (68 patients) for which they received a placebo intravenously every 8 hours. Antibiotic or placebo was administered before chest tube insertion and continued until the time of chest tube removal. The majority of patients underwent chest tube placement in the emergency room with a small number of delayed pneumothoraces (4 patients) treated after admission. In the 71 patients receiving antibiotic, 7 complications (1 pleural effusion, 2 chest tube reinsertions, 4 additional chest tubes) occurred, none of which were infectious. In the 68 patients receiving placebo, 7 complications (2 empyemas, 2 pneumonias with effusions, 1 pleural effusion, 2 chest tube reinsertions) occurred, 4 of which were infectious and required antibiotic intervention (P = 0.05, Fisher's exact test). This study showed that patients receiving antibiotics have a significantly reduced incidence of infectious complications and suggests that patients who undergo tube thoracostomy for chest trauma would benefit from administration of prophylactic antibiotics.

A method for management of extraperitoneal pelvic bleeding secondary to penetrating trauma.

Several techniques for the management of bleeding from extraperitoneal pelvic bullet tracks have been described in the literature. Some methods described include packing followed by direct control of the bleeding and use of thumbtacks. These methods often incur significant blood loss and prolonged operative times. We present our experience with an alternative method, which involves tamponade of the bleeding using a Foley catheter. This method has been used on 11 consecutive patients with successful control of life-threatening hemorrhage.

Colostomy in penetrating colon injury: is it necessary?

OBJECTIVE: To compare in a randomized prospective manner the complication rates associated with colostomy versus primary repair in penetrating colon injuries. METHODS: During a 38-month period, 114 patients with penetrating wounds of the colon were entered into a randomized prospective study at an urban Level I trauma center. The patients were randomized to a primary repair group or a diversion group. Randomization was completely independent of any risk factors, including number of abdominal organ systems injured, extent of fecal contamination, blood loss, presence of shock (systolic blood pressure < 80), time from injury to operation, and severity of colon injury. Five patients initially entered in the study died in the immediate postoperative period (< 24 hours) and were removed from the study because their deaths were unrelated to their colon injuries. RESULTS: A total of 109 patients were studied, of which 56 were randomized to primary repair and 53 to diversion (39 colostomies, 14 ileostomies). The average age for the primary repair group was 28.5 years and for the diversion group it was 26.8 years. The average Penetrating Abdominal Trauma Index for the primary repair group was 24.3 and for the diversion group it was 22.8. There were 11 (20%) septic-related complications in the primary group versus 13 (25%) in the diversion group. Complication rates in the presence of significant fecal contamination, shock, significant blood loss (> 1000 mL), more than two organ systems injured and extent of colon injury were all higher in the diversion group. There was one mortality in the diversion group and two in the primary repair group. CONCLUSIONS: The authors conclude that all penetrating colon injuries in the civilian population should be primarily repaired.

Clinical and electrophysiologic features and role of catheter ablation techniques in adult patients with automatic atrioventricular junctional tachycardia.

A total of 8 patients with junctional tachycardia (JT) were included for study. Patients with JT had a supraventricular arrhythmia that was initiated by a junctional complex without PR prolongation and episodes of atrioventricular (AV) dissociation. JT could not be initiated by pacing and occurred either spontaneously (3 patients) or with isoproterenol (5 patients). Tachycardia could be consistently terminated by either carotid sinus massage (1 patient), intravenous adenosine (2 patients), or critically timed ventricular premature complexes (3 patients). In 6 of the 8 other patients, tachycardia foci (atrial or ventricular) or mechanisms (AV node reentry) were found. Two patients underwent complete AV junctional ablation and 2 had termination of tachycardia without change in the AV conduction by perinodal application of radiofrequency lesions. AVJT appears to be due to abnormal automaticity and may be successfully ablated by application of radiofrequency energy to perinodal areas.

Clinical and electrophysiologic spectrum of fascicular tachycardias.

The purpose of this report is to describe the clinical and electrophysiologic findings for patients with fascicular tachycardia (FT). Eight patients with FT, defined as tachycardia with HV interval during tachycardia less than that of HV of conducted impulses, were studied. ECG findings during FT included right bundle block and superior axis (four patients), right bundle branch block and inferior axis (one patient), and nonspecific intraventricular conduction delay (three patients). In three patients, entrainment as well as the ability to initiate and terminate the tachycardia favored a reentrant mechanism. In others, tachycardia initiation only over a critical range of paced cycle lengths and the incessant nature of the tachycardia or the presence of other atrial or ventricular foci favored a mechanism of either abnormal automaticity or triggered rhythms. Catheter ablation was successful in two of five patients in whom it was attempted. In conclusion, the ECG expression of FT is variable, depending on the site of origin of the arrhythmia in the ventricular specialized conduction system. Similarly, a variety of mechanisms and different foci may be associated with FT. Selected individuals may respond to catheter ablative therapy.