Intracranial pressure monitoring and outcomes after traumatic brain injury.

OBJECTIVE: Uncontrolled intracranial hypertension after traumatic brain injury (TBI) contributes significantly to the death rate and to poor functional outcome. There is no evidence that intracranial pressure (ICP) monitoring alters the outcome of TBI. The objective of this study was to test the hypothesis that insertion of ICP monitors in patients who have TBI is not associated with a decrease in the death rate. DESIGN: Study of case records. METHODS: The data files from the Ontario Trauma Registry from 1989 to 1995 were examined. Included were all cases with an Injury Severity Score (ISS) greater than 12 from the 14 trauma centres in Ontario. Cases identifying a Maximum Abbreviated Injury Scale score in the head region (MAIS head) greater than 3 were selected for further analysis. Logistic regression analyses were conducted to investigate the relationship between ICP and death. RESULTS: Of 9001 registered cases of TBI, an MAIS head greater than 3 was recorded in 5507. Of these patients, 541 (66.8% male, mean age 34.1 years) had an ICP monitor inserted. Their average ISS was 33.4 and 71.7% survived. There was wide variation among the institutions in the rate of insertion of ICP monitors in these patients (ranging from 0.4% to over 20%). Univariate logistic regression indicated that increased MAIS head, ISS, penetrating trauma and the insertion of an ICP monitor were each associated with an increased death rate. However, multivariate analyses controlling for MAIS head, ISS and injury mechanism indicated that ICP monitoring was associated with significantly improved survival (p < 0.015). CONCLUSIONS: ICP monitor insertion rates vary widely in Ontario's trauma hospitals. The insertion of an ICP monitor is associated with a statistically significant decrease in death rate among patients with severe TBI. This finding strongly supports the need for a prospective randomized trial of management protocols, including ICP monitoring, in patients with severe TBI.

Epidemiology of maxillofacial injuries at trauma hospitals in Ontario, Canada, between 1992 and 1997.

BACKGROUND: The purpose of this study was to review the epidemiology of maxillofacial skeletal injuries in severely injured patients admitted to trauma hospitals in Ontario, Canada, with an Injury Severity Score > 12. METHODS: The Ontario Trauma Registry was accessed to examine the epidemiology of maxillofacial skeletal injuries in severely injured patients treated at 12 trauma hospitals in the province of Ontario, Canada, between 1992 and 1997. Data were collected prospectively, and a descriptive analysis was performed to determine the pattern of maxillofacial injuries, including patient age, sex distribution, etiology of injury, time of injury, and injury profile. RESULTS: There were 2,969 patients that met the inclusion criteria. The median age was 25 years, and men were injured at a 3:1 ratio over women. Most severely injured patients with maxillofacial fractures were injured as a result of motor vehicle collision (70%), with only 33% of the patients restrained with a seat-belt. The temporal distribution of injuries showed that most injuries occurred during evening hours, on weekends, and in the summer. The largest number of fractures was found in the maxilla and orbital bones. The Injury Severity Score of the patients in this study ranged from 13 to 75, with a median of 25. The injury most commonly associated with maxillofacial fractures was injury to the head and neck area. Of patients with injury to the head and neck, most had an altered level of consciousness or injuries to the skull, brain, or cranial vessels. CONCLUSION: Many severely injured patients have maxillofacial injuries. Long-term collection of epidemiologic data regarding maxillofacial fractures is important for the evaluation of existing preventative measures and useful in the development of new methods of injury prevention. Furthermore, insight into the epidemiology of facial fractures and concomitant injuries is an integral component in evaluating the quality of patient care, developing optimal treatment regimens, and making decisions regarding appropriate resource and manpower allocations.

Open or closed diagnostic peritoneal lavage for abdominal trauma? A meta-analysis.

OBJECTIVES: To perform a meta-analysis of prospective, randomized controlled trials comparing the closed and open technique of diagnostic peritoneal lavage (DPL) in trauma patients to determine whether there are any difference in outcomes. METHODS: A search of MEDLINE database of English language articles published from 1977 to 1999 was conducted by using the terms diagnostic peritoneal lavage, trauma, and randomized controlled trials. A manual search and Cochrane Library database search was also conducted. Seven randomized controlled trials, including a total of 1,126 patients were identified that compared closed versus open technique. Two reviewers assessed the trials independently. Trial quality was critically appraised by using the Jadad Instrument, a validated published quality scale. Data extraction of major complications, technical difficulties, procedure times, and false-negative and false-positive rates was carried out. The fixed effects model was used for statistical analysis. The Peto odds ratio (OR), weighted mean differences and 95% confidence intervals (95% CI) were calculated. RESULTS: The overall quality of studies was poor (mean, 2.4/7). Major complications did not differ significantly between closed versus open technique (OR, 0.65; 95% CI, 0.15 to 2.92. Technical failures and difficulties were significantly higher in the closed group, i.e., OR 4.33 (95% CI, 1.96 to 9.56) and OR 4.19 (95% CI, 2.842 to 6.19), respectively. Accuracy of closed and open DPL was comparable with no difference in false-negative or false-positive rates between the two techniques. Procedure time was consistently lower in the closed technique. CONCLUSIONS: The closed DPL technique is comparable to the standard open DPL technique in terms of accuracy and major complications. The advantage of reduced time to perform the closed DPL is offset by the increased technical difficulties and failures of this group. Therefore, any significant benefit of routine closed DPL in improving outcomes can be excluded with more confidence based on pooled data than by the individual trials alone.

Autopsies and death certification in deaths due to blunt trauma: what are we missing?

OBJECTIVES: To determine the frequency, body region and severity of injuries missed by the clinical team in patients who die of blunt trauma, and to examine the accuracy of the cause of death as recorded on death certificates. DESIGN: A retrospective review. SETTING: London Health Sciences Centre, London, Ont. PATIENTS: One hundred and eight deaths due to blunt trauma occurring during the period Apr. 1, 1991, to Mar. 31, 1997. Two groups were considered: clinically significant missed injuries were identified by comparing patient charts only (group 1) and more detailed injury lists from the autopsies and charts of the patients (group 2). OUTCOME MEASURES: Chart and autopsy findings. RESULTS: Of the 108 patients, 78 (72%) were male, and they had a median age of 39 years (range from 2 to 90 years). The most common cause of death was neurologic injury (27%), followed by sepsis (17%) and hemorrhage (15%). There was disagreement between the treating physicians and the causes of death listed on the death certificate in 40% of cases and with the coroner in 7% of cases. Seventy-seven clinically significant injuries were missed in 51 (47%) of the 108 patient deaths. Injuries were missed in 29% of inhospital deaths and 100% of emergency department deaths. Abdominal and head injuries accounted for 43% and 34% of the missed injuries, respectively. CONCLUSIONS: The information contained on the death certificate can be misleading. Health care planners utilizing this data may draw inaccurate conclusions regarding causes of death, which may have an impact on trauma system development. Missed injuries continue to be a concern in the management of patients with major blunt trauma.

Standardized gentamicin dosing enhances peak serum concentrations.

The objectives of this study were to determine if a standardized gentamicin dosing protocol would improve clinical effectiveness, yield higher peak serum concentrations, and improve the success rate of attaining peaks in the desired range when compared with empiric dosing practices used by prescribers. The study was conducted as a before-after program effectiveness evaluation in non-critically ill patients, aged 16-65 y with stable renal function, who were prescribed gentamicin. A standardized dose of 2 mg/kg (ideal or adjusted weight) was administered intravenously every 12 h in the intervention phase. Response to therapy (time to defervescence, white cell count, reinstitution of antibiotic therapy), serum concentrations (peaks > 10 mumol/L (5.6 mg/L) and troughs < 4 mumol/L (2.2 mg/L)), and toxicity were monitored in both groups. Thirty-four consecutive patients were enrolled into the control phase and an equal number into the intervention phase. Surgical patients comprised the majority of the study population. Desired peak concentrations were attained in 97% of intervention vs. 59% of control patients (p < 0.001). Mean peak serum concentrations were higher in the intervention phase than in the control phase, 16.1 mumol/L vs. 11.2 mumol/L (p < 0.001), respectively. Median time to become afebrile trended toward a statistical decrease in the intervention as compared to the control group, 3 vs. 5 d (p = 0.076), respectively. There was no significant difference in clinical effectiveness nor in the occurrence of nephro- or ototoxicity. Continued evaluation of this dosing protocol is warranted.

From premise to principle: the impact of the gut hypothesis on the practice of critical care surgery.

Clinical decision making is ideally founded on evidence of efficacy derived from well-designed randomized clinical trials. In reality, such evidence is rarely available to the surgeon caring for the patient with multiple trauma or who is critically ill, and complex management decisions must be made by less rigorous, more subjective means. An understanding of the normal biologic state and its alterations during disease has long been a fundamental component of medical education. Although such an understanding does not provide practitioners with grounds for assuming therapeutic efficacy in a particular patient, it does shape their perception of the important principles that guide the decision-making process. In contrast to evidence-based medicine--the making of therapeutic decisions through the systematic synthesis of results of clinical trials--a knowledge of pathobiology supports a complementary approach that the authors term "inference-based medicine"--the use of insights from studies in basic biology to establish principles that guide the practitioners' approach to groups of patients. The impact of a relatively new area of biologic investigation into the effects of the gut flora on systemic homeostasis, and the perturbations of this process in trauma and critical illness are reviewed. Re-emergence of the "gut hypothesis" has had a relatively modest effect if measured by the introduction of promising new forms of specific therapy. However, these investigations have resulted in a fundamental paradigm shift in two important areas in the practice of trauma and critical care surgery: the use of antimicrobial agents and the route of nutritional support.

Attitudes toward trauma care of surgeons practising in Ontario.

OBJECTIVE: To assess the attitudes of practising surgeons in the province of Ontario toward issues in trauma care management. DESIGN: A survey by questionnaire. SETTING: The study was carried out in a university-affiliated hospital. The survey respondents generally practised in a nonteaching setting; 48% were over the age of 50 years; 81% worked in an institution with 24-hour in-house physician coverage for the emergency department. SUBJECTS: All 2294 surgeons registered with the Ontario Medical Association were surveyed by completion and return of a questionnaire; 191 surgeons were registered in Ontario but were not practising in the province and were excluded from the survey. Questionnaires were completed by 575 surgeons, but 49 were no longer in active practice, so 526 responses form the basis of this analysis. RESULTS: The response rate to the questionnaire was 27%. One-third of the respondents wished to treat no trauma patients at all; 47% believed that trauma patients had a negative impact on their surgical practice; only 19% considered that trauma patients had a positive impact. Surgeons had negative attitudes toward trauma because of the night and weekend profile of trauma, its effect on elective surgical practice, the poor rate of reimbursement for time spent in trauma management, and the potential medicolegal liability of trauma cases. CONCLUSIONS: These results suggest that there are few surgeons in Ontario who are truly committed to providing care to the injured patient. Strategies to overcome the perceived negative aspects of trauma care must be addressed because a crisis in the availability of surgeons to provide this care seems inevitable.

Pentoxifylline does not prevent microvascular injury in normotensive, septic rats.

OBJECTIVE: To determine if treatment with pentoxifylline would decrease the tissue injury that occurs in a normotensive model of sepsis. DESIGN: Random assignment to control, cecal ligation-perforation, or cecal ligation-perforation plus pentoxifylline groups for a 24-hr study. SETTING: Animal laboratory. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: Sepsis was induced by cecal ligation-perforation with aggressive fluid resuscitation (normal saline 10 mL/kg/hr). Pentoxifylline was administered as a 2-mg/kg bolus, followed by a continuous infusion of 6 mg/kg/hr. MEASUREMENTS AND MAIN RESULTS: Compared with controls, rats in the cecal ligation-perforation group had an increased heart rate (432 +/- 12 vs. 399 +/- 10 beats/min) and respiratory rate (129 +/- 6 vs. 94 +/- 7 breaths/min). Blood pressure was slightly decreased (104 +/- 4 vs. 125 +/- 5 mm Hg), while cardiac index was not significantly different (50.1 +/- 5.7 vs. 40.7 +/- 3.9 mL/min/100 g). Blood pressure (103 +/- 4 mm Hg) was the only parameter that was significantly different in the cecal ligation-perforation plus pentoxifylline group compared with controls. When compared with controls, tissue wet/dry weight ratios were increased in the diaphragm of the cecal ligation-perforation group and in the liver, pancreas, small bowel, and large bowel of the cecal ligation-perforation, and the cecal ligation-perforation plus pentoxifylline groups. Tissue/plasma albumin ratios were increased in the diaphragm of the cecal ligation-perforation group and in the liver, pancreas, and large bowel of the cecal ligation-perforation and the cecal ligation-perforation plus pentoxifylline groups. There were no significant differences between the cecal ligation-perforation and the cecal ligation-perforation plus pentoxifylline groups. CONCLUSIONS: Normotensive sepsis is accompanied by increased vascular permeability in the diaphragm and intra-abdominal organs. Pentoxifylline appears to attenuate some of the systemic manifestations of sepsis. However, pentoxifylline did not prevent the development of protein-rich tissue edema.

Pneumoperitoneum after laparoscopic cholecystectomy: frequency and duration as seen on upright chest radiographs.

OBJECTIVE: This study aimed to determine the frequency and duration of pneumoperitoneum after laparoscopic cholecystectomy, as detected on upright chest radiographs. MATERIALS AND METHODS: Fifty-five patients who underwent laparoscopic cholecystectomy were studied prospectively. Upright posteroanterior chest radiographs were obtained 6 hr after surgery (day 1); additional radiographs were obtained on days 2, 4, 7, and 14, if required, until the pneumoperitoneum resolved. A perpendicular measurement of any pneumoperitoneum detected between the diaphragm and the liver was obtained. The pneumoperitoneum was graded as absent, trace (1-5 mm), mild (6-10 mm), or moderate (10-15 mm). RESULTS: No evidence of pneumoperitoneum was seen on chest radiographs taken 6 hr after surgery (day 1) in 27 (54%) of the 50 patients who completed the study. Of the remaining 23 patients (46%), all but one showed resolution of the pneumoperitoneum in the first week. Of these 23 patients, 17 showed trace pneumoperitoneum and six showed mild pneumoperitoneum on chest radiographs. CONCLUSION: Despite the use of carbon dioxide gas during laparoscopic cholecystectomy, a significant number of patients have postsurgery pneumoperitoneum that is visible on upright chest radiographs. The pneumoperitoneum resolves in most patients within the first week after surgery.

Preoperative transdermal scopolamine does not reduce the level of nausea and frequency of vomiting after laparoscopic cholecystectomy.

OBJECTIVE: To determine the efficacy of scopolamine administered transdermally before laparoscopic cholecystectomy as a means of reducing postoperative nausea and vomiting. DESIGN: A randomized, double-blind, placebo-controlled study. SETTING: A tertiary-care, university-affiliated hospital. PATIENTS: A volunteer sample of 125 men and women between 20 and 60 years of age scheduled to undergo elective laparoscopic cholecystectomy. Expectant or nursing mothers were excluded, and 35 patients were excluded from the final analysis because of protocol violations. Forty-three patients received scopolamine and 47 patients received a placebo. INTERVENTION: A skin patch (scopolamine or placebo) was applied behind the right ear on the evening before operation and maintained for at least 24 hours postoperatively. MAIN OUTCOME MEASURES: The postoperative level of nausea assessed by the patient on a visual analogue scale, the frequency of vomiting and the frequency of antiemetic use. RESULTS: There was no significant difference in the level of nausea or in the frequency of emesis or use of antiemetics in the first 24 hours postoperatively between the control and study groups. Furthermore, there was no difference in the overall frequency of side effects. However, visual blurring was experienced by six patients in the study group compared with one in the control group (p = 0.082). CONCLUSION: Scopolamine administered transdermally before laparoscopic cholecystectomy does not reduce the frequency or level of nausea and vomiting postoperatively.

Attitudes of surgical residents toward trauma care: a Canadian-based study.

Surgical residents (n = 330) registered in training programs in the province of Ontario, Canada were surveyed about their attitudes toward trauma care related issues. Questionnaires were returned by 48%. Overall, 84% felt that their clinical exposure to trauma was adequate; 78% noted that the emphasis placed on trauma topics in their educational programs was appropriate; 50% spend > 10% of their current clinical time in trauma care. Orthopedic residents (n = 43) were different; 79% devoted > 10% and 29% > or = 30% of their time to trauma. Future clinical activity in trauma as practicing surgeons was expressed by 83% of the trainees: 31% intended < 10%, 46% 10%-30%, and 6% > 30% of their future practices to be related to trauma. The major positive factors of trauma were the scope and excitement of trauma care. The major negative factors were the night/weekend activity and the time away from family. We are encouraged by the results of this survey in that a significant number of residents perceive trauma as a clinical endeavor to be incorporated into their future surgical practices.

Postoperative utilization of critical care services by cardiac surgery: a multicenter study in the Canadian healthcare system.

OBJECTIVES: To describe patterns of critical care services used after cardiac surgery and to evaluate whether variations in the process of care influence outcome. DESIGN: Multicenter, prospective study. SETTING: A convenience sample of four cardiac surgical units: three in university-affiliated (teaching) hospitals and one in a nonteaching regional referral center. PATIENTS: A "consecutive sample" of 335 patients after cardiac surgery in four hospitals. INTERVENTIONS: Data were collected regarding all cardiac surgery patients admitted to the critical care units in the four test hospitals. MEASUREMENTS AND MAIN RESULTS: The critical care unit and hospital lengths of stay and survival were followed. The Therapeutic Intervention Scoring System (TISS) was used to assess the intensive care unit (ICU) interventions used during the first 24 hrs in the ICU and for the final 24 hrs before discharge from the ICU. The severity of illness on admission was assessed using the Acute Physiology and Chronic Health Evaluation (APACHE) scoring system. For patients having similar procedures (e.g., aortocoronary bypass and nonaortocoronary bypass procedures) and with similar outcome (mortality/total hospital length of stay), we found significant differences in the pattern of ICU resource utilization among hospitals. Significant (p < .05) differences in unit length of stay were related to varying factors in different hospitals. In hospital unit A, the type of procedure and preoperative chronic health status influenced unit length of stay (aortocoronary bypass 2.8 +/- 1.7 days; nonaortocoronary bypass 8.7 +/- 8.9 days) because length of stay was different for differing procedure groups. In hospital unit B, the critical care management system and lack of step-down (intermediate care) unit availability resulted in an increased unit length of stay for aortocoronary bypass patients (5.1 +/- 4.5 days) as compared with the other units (mean ICU lengths of stay of 2.8, 2.3, and 3.0 days, respectively). Unit B kept patients for monitoring purposes and had a reduced need for critical care nursing on the day of discharge (TISS = 7.5 +/- 5.5) as compared with the other units (mean TISS scores of 27.4, 23.2, and 21.5). CONCLUSIONS: Significant differences exist among hospitals in the same healthcare system in the utilization of critical care services for cardiac surgery. In spite of these differences, for similar patient "input," the outcome (mortality and hospital lengths of stay) appeared similar. Assessments of utilization of critical care must focus on more detailed specific issues than unit length of stay, and must include factors such as availability of intermediate care areas, the unit management system, chronic health status, and the operative procedures performed, if a utilization management process is to effect improved resource use in critical care.

Induced immunoglobulin secretion by T-cell-replacing products from blunt trauma patients.

The capacity to induce immunoglobulin (Ig) secretion by soluble T-cell-replacing (TCR) factors derived from alloantigen-stimulated T lymphocytes of blunt trauma patients (n = 15, mean ISS = 24) was examined in Staphylococcus aureus (SAC)-activated normal B-cell cultures. The majority of the patients studied demonstrated a profound suppression of the T-cell-dependent, pokeweed-mitogen-induced Ig production. However, the activity to induce Ig secretion associated with TCRs from the same patients was not reduced compared with that of TCRs from normal subjects. IgM synthesis was normal and IgG secretion induced by TCRs was within the control range (in 6 of 15 patients) or significantly higher (p less than 0.05) than that in the remaining patients. Both patient-derived and control TCRs failed to induce Ig synthesis in cultures of resting B cells and had comparable mitogenic effects on normal SAC-activated and phytohemagglutinin A-activated B and T lymphocytes, respectively. Thus, the intrinsic ability of T lymphocytes to produce B-cell helper factors appears to be unaffected following blunt trauma. Suppression of the T-cell-regulated Ig secretion in traumatized patients may therefore reflect an altered B lymphocyte response to such factors.

History of laparoscopic surgery.

Since the beginning of the 20th century physicians have promoted laparoscopy as a valuable adjunct to the diagnosis of diseases of the abdominal cavity. Laparoscopy, however, failed to become popular among abdominal surgeons until the advent of laparoscopic cholecystectomy. This single new operative approach to the treatment of gallbladder stones gave rise to such enthusiasm among general surgeons that other innovative laparoscopic procedures are now being promoted in ever-increasing numbers. The general surgeon has again become the leader in the introduction of a new surgical approach. This new technique must be developed with great care, and there must be rigorous criteria for its use, critical analysis of the technique and honest reporting of results.

Laparoscopic surgery--basic armamentarium.

The introduction of laparoscopic techniques into standard intracavitary surgery has received widespread acceptance in North American surgical practice in a very short time. To complete these procedures successfully a basic armamentarium is required by surgeons. The equipment should provide safe conduct of the procedure and maximum flexibility in the types of surgical procedures to be undertaken. The basic laparoscopic equipment needed to facilitate minimal-access-site surgery is reviewed, from the operating table and lighting in the operating room through optics, cameras and television monitors to the instruments and agents needed for the surgical techniques and for securing hemostasis.

Laparoscopic cholecystectomy: strategy and concerns.

After briefly describing the first laparoscopic cholecystectomy performed by Philippe Mouret, the authors review some of the differences in strategy, management and concerns between conventional and laparoscopic cholecystectomy. They address the problems relating to the required skills of triangulation and camera handling, the presence of common-duct stones and concomitant disease, the issues of drainage, hemostasis, access in difficult cases, iatrogenic trauma to the bile ducts and pertinent differences in cardiorespiratory function.

Laparoscopic cholecystectomy: trans-Canada experience with 2201 cases.

The authors carried out a prospective review of the initial and consecutive experience with laparoscopic cholecystectomy of 58 surgeons from 31 teaching and nonteaching institutions throughout Canada. The perioperative morbidity of 2201 cases is described, with special attention to iatrogenic complications. The data suggest that complications, including bile-duct injury, are not frequent. Pneumonia and wound infection rates appear lower than after open surgery. There were no deaths. Laparoscopic cholecystectomy is replacing open cholecystectomy for the management of symptomatic cholelithiasis.