G. Tom Shires

Occult diaphragmatic injury from stab wounds to the lower chest and abdomen.

Ninety-five patients with stab wounds to the lower chest and abdomen underwent routine abdominal exploration. Eighteen of these patients had diaphragmatic injury and in five patients it was the only injury found. Isolated diaphragmatic injury in asymptomatic patients cannot be reliably delineated by either serial physical examination or peritoneal lavage. Delayed recognition of incarcerated diaphragmatic hernia after stab wounds to the lower left chest and upper abdomen has an associated mortality rate of 36%. The anatomic area of concern can be defined as stab wounds that penetrate the left side of the chest below the fourth intercostal space anteriorly, the sixth intercostal space laterally, and the tip of the scapula posteriorly. Exploratory laparotomy is necessary in these patients until a reliable nonoperative method is established that can exclude injuries to the diaphragm.

Preoperative Characteristics Predicting Intraoperative Hypotension and Hypertension Among Hypertensives and Diabetics Undergoing Noncardiac Surgery

We prospectively studied patients with hypertension and diabetes undergoing elective noncardiac surgery with general anesthesia to test the hypothesis that patients at high risk for prognostically significant intraoperative hemodynamic instability could be identified by their preoperative characteristics. Specifically we hypothesized that patients with a low functional capacity, decreased plasma volume, or significant cardiac comorbidity would be at high risk for intraoperative hypotension and those with a history of severe hypertension would be at risk for intraoperative hypertension. Patients who had a preoperative mean arterial pressure (MAP) ≥110, a walking distance of less than 400 m, or a plasma volume less than 3000 cc were at increased risk of intraoperative hypotension (i.e., more than 1 hour of ≥20 mmHg decreases in the MAP). Hypotension was also more common among patients having intra-abdominal or vascular surgery, and among those who had operations longer than 2 hours. Patients older than 70 years or with a decreased plasma volume were at increased risk of having more than 15 minutes of intraoperative elevations of 2:20 mmHg over the preoperative MAP in combination with intraoperative hypotension; this was also more common when surgery lasted more than 2 hours. Patients who had intraoperative hypotension tended to have an immediate decrease in MAP at the onset of anesthesia and were often purposefully maintained at MAPs less than their usual level during surgery with fentanyl and neuromuscular blocking agents. Patients who had intraoperative hyper/hypotension tended to have repeated elevations in MAP above their preoperative levels during the course of surgery, and such elevations precipitated interventions with neuromuscular blocking agents and/or fentanyl. Neither pattern was more common among patients who developed net intraoperative negative fluid balances. Both hypotension and hyper/hypotension were associated with increased renal and cardiac complications after operation. Patients with cardiac disease, especially diabetics, and those with negative fluid balances also had increased complications. Preoperative characteristics influence the susceptibility to intraoperative hypotension and hypertension, which are related to postoperative complications.

Glutamine or fiber supplementation of a defined formula diet: Impact on bacterial translocation, tissue composition, and response to endotoxin

Despite provision of adequate calories, defined formula diets in rats lead to bacterial translocation (BT), fatty infiltration of the liver, and an increased susceptibility to endotoxin. These deleterious effects may be due in part to a loss of intestinal barrier integrity resulting from bowel atrophy. Defined formula diets lack both glutamine and fiber, substances which may help maintain intestinal mass. To determine whether supplementation of defined formula diets with either glutamine or fiber might prevent bowel atrophy and, thus, BT, hepatic steatosis, and the altered response to endotoxin, Wistar rats were fed (1) defined formula diet ad libitum (DFD), (2) (DFD + 2% (w/v) glutamine, (GLUT), or (3) DFD + 2% (w/v) psyllium (FIBER). Rats given standard food isocalorically pair-fed to DFD were used as controls. Nutritional status was assessed by daily weight gain, as well as the ability to maintain serum albumin, hematocrit and white blood counts. After 2 weeks of these feeding regimens, animals were sacrificed, and organ weights and composition were determined, with rates of bacterial translocation determined by mesenteric lymph node, abdominal viscera, and cecal cultures. Additional animals receiving the same experimental diets were subsequently challenged with endotoxin and observed for mortality with rates of post-endotoxin BT and the responses of acute phase proteins and cytokines measured. All dietary regimens resulted in equivalent weight gain and other nutritional parameters. Both glutamine and fiber supplementation maintained small bowel mass, but only GLUT preserved normal jejunal mucosal architecture. Neither fiber nor glutamine supplementation prevented cecal bacterial overgrowth or BT, resulting from the DFD.(ABSTRACT TRUNCATED AT 250 WORDS)

Peritoneal lavage in blunt abdominal trauma

Diagnosis of blunt abdominal trauma is frequently complicated by the presence of associated multiple system injuries. Diagnostic needle paracentesis has been advocated by numerous authors for many years. If nonclotting blood is recovered from the peritoneal cavity after taps in two or four quadrants, the accuracy of this adjunctive procedure has been reported as high as 95 per cent in predicting intraabdominal injury. The chance of obtaining positive results of the tap seems to be directly related to the amount of blood in the peritoneal cavity. Paracentesis is a simple quick procedure that has relatively few complications. Although abdominal paracentesis is accurate if results are positive, no information is gained if the result is negative. The major objection to the use of this test is the high percentage of falsenegative results. Because of the lack of reliability attached to negative results on paracentesis, other procedures have been sought to detect intra-abdominal injury. Canizaro, Fitts, and Sawyer [I] described the use of intraperitoneal saline infusions in animals in 1964. They consistently recovered blood-stained fluid in those animals which previously had blood injected into the peritoneal cavity and subsequently had negative results on abdominal paracentesis. In 1965 Root et al [2] described the technic of peritoneal lavage in patients. A follow-up study published in 1970 reported 304 patients in whom a 96 per cent accuracy rate was obtained [3]. This stimulated the intro-

Response of extravascular lung water to intraoperative fluids.

The effect of Ringers Lactate (RL) and a colloid containing salt solution Plasmanate (PL) on extravascular lung water (EVLW) during aortic surgery was evaluated in a prospective study of 18 patients. Measured blood loss was replaced with packed red blood cells. In addition to red blood cell replacement, either RL or PL was infused (1) to maintain the cardiac output (CO) equal to or greater than the preoperative value, (2) to maintain the pulmonary capillary wedge pressure (PCWP) plus or minus 2 mmHg of preoperative values, and (3) to keep the urinary output greater than or equal to 30 cc/ hr. Cardiac output, EVLW, PCWP, serum colloid osmotic pressure (COP), and intrapulmonary shunt fraction (Qs/Qt) were measured serially. All baseline values were similar between groups. The groups were well matched for age, associated disease, operating time, blood loss, and blood transfusions. During operation, the RL group required two times the rate of infusion of the PL group. Urine flow rates were similar on the day of surgery, but by postoperative days one and two, the PL group had approximately one-half of the urine flow rate compared to the RL group. Cardiac output and Qs/Qt increased in both groups. EVLW did not change after operation in either group, despite marked decrease in COP in the RL group. These data indicate that crystalloid resuscitation to physiologic endpoints does not increase extravascular lung water. Thus, manipulation of COP by PL was unnecessary in these patients.

Influence of hypercortisolemia on soluble tumor necrosis factor receptor II and interleukin-1 receptor antagonist responses to endotoxin in human beings

BACKGROUND We have previously reported that the antecedent administration of glucocorticoids altered both the hormonal and proinflammatory cytokine responses to lipopolysaccharide (LPS) when administered to human volunteers. In that study, subjects with vastly exaggerated levels of tumor necrosis factor (TNF) and interleukin (IL)-6 12 and 144 hours after cortisol infusion exhibited hemodynamic and hormonal responses no different from those of untreated subjects after endotoxin. The current study examined levels of the antiinflammatory cytokines interleukin-1 receptor antagonist (IL-1ra) and soluble receptors to tumor necrosis factor (sTNF-R) in the same setting of the previous report. METHODS Hydrocortisone succinate was infused into healthy volunteers. LPS was then injected immediately or was delayed by 6, 12, or 144 hours (C, C-6, C-12, and C-144, respectively). Subjects receiving LPS alone served as controls. Plasma was analyzed to determine levels of TNF, sTNF-R and IL-1ra by enzyme-linked immunosorbent assay before administration of LPS and at 30-minute intervals after administration of LPS for 6 hours. RESULTS Levels of sTNF-R increased after LPS administration in all groups (p < 0.05 versus baseline) with a significantly higher level recorded in the subjects having received hydrocortisone 144 hours before (C-144, p < 0.05 versus all other groups). TNF levels remained undetectable in association with immediate infusion of LPS (C) and the relatively short delay group (C6). This cytokine peaked 90 minutes after LPS in all other groups, with a significantly higher peak in the C-144 subjects when compared with controls. IL-1ra levels rose in all groups but to a lesser extent in the C group (p < 0.05). CONCLUSIONS These data confirm that glucocorticoids influence the production of both sTNF-R and IL-1ra. The potential for an exaggerated response of sTNF-R exists for an extended period of time after exposure to glucocorticoids.

Management of injuries to the inferior vena cava

Abstract 1. 1. Forty-two instances of injury to the inferior vena cava were found at laparotomy during the past ten years at Parkland Memorial Hospital. Of this group twenty-five survived, yielding a mortality of 40.5 per cent. 2. 2. Three principal factors determining survival were associated major vessel injury, the level of inferior vena cava injury and whether or not the vessel was actively bleeding at laparotomy. The latter seems to be the most important factor. 3. 3. All retroperitoneal hematomas should be explored. In 75 per cent of these cases, there was an additional reason to explore the retroperitoneal area. 4. 4. Suture repair by the technics outlined was the preferred method of treatment. Ligation was occasionally necessary if the injury was below the renal veins and primary repair could not be accomplished. 5. 5. It is essential to have a set of major vascular instruments immediately available when treating intra-abdominal trauma.

Gastric secretory and splanchnic blood flow studies in man after severe trauma and hemorrhagic shock

Abstract A group of thirty-three patients with severe multiple trauma and hemorrhagic shock and a group of nineteen normal control subjects were studied in a special trauma research unit to determine the effect of severe acute stress on multiple aspects of human gastric secretion and splanchnic blood flow in relation to stress ulceration. Simultaneous studies of gastric acid, pepsin, nondialyzable solids, fucose, sialic acid, and total splanchnic blood flow were carried out on both patients and control subjects. These studies were performed during basal conditions over a period of two hours and also for two hours after subcutaneous injection of Histalog. On the basis of these studies, it was concluded that excessive acid or pepsin secretion or deficient quantitative or qualitative gastric mucus production was probably not a significant etiologic factor in the production of gastroduodenal stress ulceration. The splanchnic blood flow studies and the presence of blood in gastric juice samples after Histalog injection in approximately 35 per cent of the severely injured patients supported previous opinions that ischemic damage to the superficial gastric mucosa may induce stress ulceration.

Differential pathophysiology of bacterial translocation after thermal injury and sepsis

Bacterial translocation (BT) occurs transiently after thermal injury and may result from an ischemic intestinal insult. To evaluate continued intestinal ischemia in the ongoing BT associated with sepsis after injury, rats were randomized to (1) 30% burn injury with Pseudomonas wound infection (BI), (2) BI + fluid resuscitation (BI + Fluid), (3) BI after allopurinol pretreatment to inhibit xanthine oxidase (BI + Allo), or (4) BI after azapropazone pretreatment to inhibit neutrophil degranulation (BI + Aza). On postburn days (PBD) 1, 4, and 7, animals were studied for evidence of BT and intestinal lipid peroxidation. BI + Fluid, BI + Allo, and BI + Aza significantly (p less than 0.05) reduced rates of BT and ileal lipid peroxidation acutely after thermal injury (PBD 1) compared to BI. All four groups had equally high rates of BT associated with the onset of sepsis (PBDs 4 and 7), without evidence of further intestinal lipid peroxidation. These data indicate that the chronic gut barrier failure associated with sepsis after injury occurs independently of continued intestinal ischemia.

Changes in intracellular sodium and potassium content of red blood cells in trauma and shock

Abstract The present study indicates that severe hemorrhagic shock of significant duration is associated with elevation of the internal sodium concentration of red blood cells. The magnitude of these changes appears to be a function of both the severity and duration of the shock process and seems to be well correlated with changes in clinical course when sequential sampling procedures are utilized. Present data are insufficient to determine the exact etiology of the red cell changes observed in profound shock. However, it can be speculated that the observed elevation in internal sodium concentration in this group of patients is only one manifestation of a process involving a generalized change in cellular composition and function during hemorrhagic shock.