Laparotomy for intra-abdominal sepsis in patients in an intensive care unit

Patients in an intensive care unit who have intra-abdominal (IA) infections producing clinical deterioration in their conditions require urgent intervention. However, detection is often difficult. To define preoperative criteria for, and improve the specificity of, laparotomy, we reviewed 100 explorations in 71 patients with suspected IA sepsis. Eighty-one explorations demonstrated an infected or ischemic process; 19 were negative. Preoperative features associated with a positive laparotomy were as follows: (1) objective evidence by physical examination, ultrasonography, or computed tomography suggesting an IA focus (89%); (2) septic shock (80%); and (3) positive blood cultures (95%). Absence of these features significantly lowered the accuracy of exploration. Septic shock or bacteremia had a 90% mortality regardless of findings at exploration. The best accuracy (89%) and survival (51%) rates were achieved with "directed" exploration before septic shock or bacteremia. Early use of sensitive detection techniques that permit directed laparotomy before septic deterioration should improve survival.

Microthrombosis during endotoxemia: potential role of hepatic versus alveolar macrophages

Macrophages (M phi) produce multiple inflammatory mediators which may contribute to the pathophysiological processes seen during sepsis. Since diffuse microthrombosis has been implicated as a potential etiology for organ dysfunction and failure in sepsis, the present study examined the production of procoagulant activity (PCA) by M phi in response to endotoxin, characterized the activity, and evaluated methods to modify the response. Since hepatic and pulmonary dysfunction is a common complication of sepsis, rabbit M phi were isolated from both pulmonary (A-M phi) and hepatic (H-M phi) sites. Both M phi populations produced PCA in response to endotoxin in vitro. There is a rapid rise in activity with a peak at 20- to 30+ fold over background levels at 8 hr poststimulation. Although similar in their ability to enhance coagulation, the two M phi PCAs were shown to differ markedly in other biochemical and functional assays. The A-M phi PCA in contrast to the H-M phi PCA, was resistant to heat inactivation, serine protease inhibition, and warfarin pretreatment, while indomethacin (a prostaglandin synthesis inhibitor) blocked A-M phi PCA production but not the H-M phi response. Corticosteroids totally blocked PCA production by both M phi populations. Endotoxin, therefore, induces a rapid increase in M phi PCA, and the magnitude and rapidity of the response argue for a potentially significant pathophysiologic role, in vivo. Although derived from a common progenitor, A-M phi and H-M phi produce a functionally discreet PCA. This differential response may partially explain the contradictory results obtained in studies using various cellular metabolism inhibitors, e.g., indomethacin and steroids.(ABSTRACT TRUNCATED AT 250 WORDS)

Potential for endotoxin-activated Kupffer's cells to induce microvascular thrombosis

The potential contribution of Kupffer's cells, le, hepatic macrophages (HM phi s) to the diffuse microvascular thrombosis seen during septicemia was evaluated by measuring the ability of a homogeneous population of explanted HM psi s to express procoagulant activity (PCA). Addition of as little as 100 ng/mL of endotoxin stimulated a 30-fold increase over control values of PCA within eight hours. This PCA was membrane associated and functioned externally to the macrophage. Sensitivity to heat (56 degrees C) and diisopropyl fluorophosphate differentiated this PCA from typical tissue thromboplastin activity. The increase in PCA was blocked by pretreatment with warfarin sodium (a phytonadione blocker) and could be restored by addition of phytonadione. These studies showed that endotoxin induces in HM psi s a significant increase in PCA, functioning like coagulation factor VII. These results support a role for Kupffer's cells in the initiation of microvascular thrombosis in endotoxemia.

Effect of acute ethanolism on the hospital course and outcome of injured automobile drivers

Acute ethanolism in automobile drivers is purported to be both protective and detrimental in susceptibility to injury from an accident. The potential influence of acute intoxication (serum ethanol greater than 100 mg/dl) on pattern and severity of injury, hospital course, and long-term outcome, including mortality, was examined in 182 consecutive automobile drivers requiring admission to a regional university trauma center during 1980. Significantly more drivers were intoxicated than not, 61% vs. 39%. Similarly, more than 75% of the intoxicated drivers were young males and more than 80% of the intoxicated drivers were felt to be negligent and at cause for the accident. However in this series, the patterns and severity of injuries, hospital course, and late outcome were unaffected by the patient's blood alcohol level. Acute alcohol intoxication apparently neither protected nor hindered the response to injury in these motor vehicle drivers.

Utilization of blood recycling in nonelective surgery

Intraoperative infusion of autologous shed blood is efficacious in elective vascular, cardiac, and orthopedic surgery. Blood recycling has also been advocated for emergency and trauma surgery. We examined 33 candidates for autotransfusion during emergency surgery. Autologous blood accounted for only 11% of the total blood replaced. Only 25 of the patients survived long enough to permit reinfusion. Because of rapid hemostasis, nine of the remaining patients (36%) received less than the 2 units necessary to be cost-effective. No evidence was found for septicemia or coagulopathy caused by autotransfusion. We concluded that, as currently applied, recycling of shed blood during emergency surgery is of value in a limited group of patients. The collection and storage of heparinized shed blood during the preoperative and early intraoperative periods, with later processing and reinfusion in selected patients, may expand its applicability.

The induction of a unique procoagulant activity in rabbit hepatic macrophages by bacterial lipopolysaccharides

Disseminated intravascular coagulation (DIC) is a common occurrence during clinical sepsis and can be induced in the experimental host by LPS. Fibrin deposition in the hepatic microcirculation has been observed within 30 min of i.v. injection of LPS. Because mononuclear phagocytes have been shown to produce a PCA after exposure to LPS, we have examined the ability of a homogeneous population of explanted hepatic macrophages to express PCA. Addition of as little as 10 ng/ml of LPS stimulated a 15- to 20-fold increase in PCA over control culture levels within 7 1/2 hr post-treatment. The PCA was found to be membrane-associated, with approximately 90 to 95% of the total PCA present in the cellular lysates, and more than 85% was inhibited by pretreatment of the cells with the diazonium salt of sulfanilic acid, an inhibitor of ecto-enzymes. In contrast to tissue thromboplastin produced by other M phi populations, the H-M phi PCA was found to be markedly sensitive both to heat inactivation at 56 degrees C and to inhibition by 1 mM DFP. Additionally, assays involving both a 1-stage coagulation test as well as an enzyme assay with a Factor Xa-specific substrate (using normal and deficient human plasmas) demonstrated that the H-M phi PCA appears to activate Factor X directly. Unlike tissue thromboplastin, the H-M phi PCA is non-dependent of Factor VII activation. These studies: 1) demonstrate the LPS induces a unique PCA in the H-M phi, and 2) support a role for the H-M phi in the initiation of DIC in endotoxemic shock.

The induction of a unique procoagulant activity in rabbit hepatic macrophages by bacterial lipopolysaccharides

Disseminated intravascular coagulation (DIC) is a common occurrence during clinical sepsis and can be induced in the experimental host by LPS. Fibrin deposition in the hepatic microcirculation has been observed within 30 min of i.v. injection of LPS. Because mononuclear phagocytes have been shown to produce a PCA after exposure to LPS, we have examined the ability of a homogeneous population of explanted hepatic macrophages to express PCA. Addition of as little as 10 ng/ml of LPS stimulated a 15- to 20-fold increase in PCA over control culture levels within 7 1/2 hr post-treatment. The PCA was found to be membrane-associated, with approximately 90 to 95% of the total PCA present in the cellular lysates, and more than 85% was inhibited by pretreatment of the cells with the diazonium salt of sulfanilic acid, an inhibitor of ecto-enzymes. In contrast to tissue thromboplastin produced by other M phi populations, the H-M phi PCA was found to be markedly sensitive both to heat inactivation at 56 degrees C and to inhibition by 1 mM DFP. Additionally, assays involving both a 1-stage coagulation test as well as an enzyme assay with a Factor Xa-specific substrate (using normal and deficient human plasmas) demonstrated that the H-M phi PCA appears to activate Factor X directly. Unlike tissue thromboplastin, the H-M phi PCA is non-dependent of Factor VII activation. These studies: 1) demonstrate the LPS induces a unique PCA in the H-M phi, and 2) support a role for the H-M phi in the initiation of DIC in endotoxemic shock.

Pyogenic osteomyelitis of axial bones following civilian gunshot wounds

A series of forty-five patients with low velocity gunshot wounds to the spine and pelvis were followed up for at least eight weeks to determine the incidence of pyogenic osteomyelitis and the role of debridement and fragment removal in its prevention. Four cases of osteomyelitis were found, and although debridement was not frequently done, the incidence of osteomyelitis was higher following debridement than it was without debridement. The most important cause appeared to be spread of contiguous intraabdominal abscesses into the injured paravertebral muscles and spine. If an intraabdominal abscess did not develop, the presence of gastrointestinal injury did not predispose the patient to osteomyelitis. Based on this study, we can conclude that debridement and fragment removal of the spine and pelvic bones are unnecessary for low velocity missile wounds.