Hemodynamic, plasma volume, and prenodal skin lymph responses to varied resuscitation regimens.

The theoretical efficacy of hypertonic saline (HS) resuscitation for hemorrhagic shock purportedly stems from the osmolar extraction of intracellular fluid into the plasma. This hypothesis presumes a concomitant expansion of the interstitial fluid space. Colloid resuscitation, in theory, expands the plasma volume by extracting interstitial fluid. These hypotheses were tested in a canine-modified Wigger's model of hemorrhagic shock. Forty, male, splenectomized dogs were anesthetized and instrumented. Animals underwent a baseline equilibration period followed by shock for 120 minutes. Each animal was randomized to one of four groups and received equal amounts of Na+ either as lactated Ringer's (LR) solution, 10% dextran 40 (Dex) in normal saline, 7.5% saline (HS), or 7.5% saline plus Dex (HSD). Parameters measured at baseline, shock, and at postresuscitation 30 minutes, 60 minutes, 90 minutes, and 120 minutes, included: mean pressure (MAP), output, pulmonary capillary wedge pressure, prenodal skin lymph flow, serum and lymph albumin, wet-to-dry skin ratios, and plasma volume. MAP, cardiac output, and plasma volume were most quickly restored with LR and Dex resuscitation (MAP = 106 and 118 mm Hg) compared to HS and HSD (MAP = 98 and 92 mm Hg). Lymph flow and lymph albumin flux were best restored with LR and HSD (mean = 85 and 48 microL/min) compared to Dex and HS (mean = 36 and 37 microL/min). Wet/dry skin ratios were greatest at 60 minutes in the LR group but similar at 120 minutes in all four groups. These data suggest that interstitial fluid space remains contracted during the first hour after HS, HSD, and Dex resuscitation compared with LR resuscitation, even though the restoration of plasma volume, MAP, and cardiac output is greatest with the Dex regimen. Further studies with total body water and intracellular water are needed in this model.

Plasma supplementation is beneficial for coagulation during severe hemorrhagic shock.

BACKGROUND: Hemorrhagic shock (HS) often causes coagulopathy due, in part, to decreased coagulation proteins. This study assessed the efficacy of fresh frozen plasma (FFP) in preventing this coagulopathy following a canine model of HS designed to mimic bleeding with shock as seen in the emergency department followed by bleeding without shock as seen during operation for control of bleeding. METHODS: Twenty-two dogs had acute HS for 2 hours followed by resuscitation with red blood cells (RBC) plus lactated ringers (LR) or RBC and LR with FFP. After resuscitation, bleeding was continued for 1 hour while intravenous replacement of RBC and LR with or without FFP was provided. Baseline, postshock, postresuscitation, post-1 hour exchange, postoperative day one and day two measurements included coagulation Factors I, II, V, VII, VIII, and X, and the prothrombin (PT), partial thromboplastin (PTT), and thrombin times (TT). RESULTS: Baseline, postshock, and postresuscitation hemodynamic responses, coagulation factor levels, and coagulation times were similar for both groups. By contrast, the 1-hour postexchange factors were depleted in the LR dogs compared to the FFP dogs. This depletion correlated with prolonged PT, PTT, and TT in the LR dogs (mean 14, 35, and 8 seconds) compared to FFP dogs (9, 24, and 6 seconds). CONCLUSIONS: Severe HS beyond one blood volume exceeds the interstitial stores of coagulation protein, thus necessitating FFP supplementation.

Prediction of rib fracture injury outcome by an artificial neural network.

Outcome-based therapy is becoming the standard for assessing patient care efficacy. This study examines the ability of an artificial neural network to predict rib fracture injury outcome based on 20 intake variables determined within 1 hour of admission. The data base contained 580 patient records with four outcome variables: Length of hospital stay (LOS), ICU days, Lived, and Died. A 522-patient training set and a 58-patient test set were randomly selected. Nine networks were set up in a feed-forward, back-propagating design with each trained under different initial conditions. These networks predicted the test set outcome variables with an accuracy as high as 98% at the 80% testing level. Internal weight matrix examination indicated that age, ventilatory support, and high trauma scores were strongly associated with both ICU days and mortality. Being female, injury severity, and injury type were associated with increased LOS. Smoking and rib fracture number were low-level predictors of the four outcome variables.

Lower esophageal sphincter dysfunction precludes safe gastric feeding after head injury.

Early nutrition is advocated for patients with head injury to counter the postinjury hypermetabolic state. The gastric route of feeding often leads to vomiting and aspiration pneumonitis. This study was designed to identify the role of lower esophageal sphincter (LES) function in this complication. The LES function was assessed within 72 hours of admission in 16 patients with a head injury and a Glasgow Coma Scale (GCS) score less than 12 (range, 3-11). Other admission assessments included an APACHE II score of 11.7, Injury Severity Score (ISS) of 30.5, and a Revised Trauma Score (RTS) of 6.4. These studies were repeated 1 week postinjury in five patients. Dysfunction of the LES was present in all 16 patients; the average gastric-to-esophageal pressure difference was -0.49 mm Hg (range, -0.59 to 2.5) compared with a normal value of greater than 20 mm Hg. The five patients restudied at 1 week had a gastric-to-esophageal pressure difference of 13.3 mm Hg (range, -3.4 to 36.6 mm Hg). The single patient with a GCS score below 12 at 1 week had a low LES tone. These data show that LES dysfunction accompanies acute head injury and contributes to aspiration pneumonitis after early gastric feeding. Nutrition in patients with low GCS scores should be parenteral or via the jejunum.

Massive steroids do not reduce the zone of injury after penetrating spinal cord injury.

The National Acute Spinal Cord Injury Study II concluded in 1990 that high-dose methylprednisolone (MP) improved neurologic recovery after acute spinal cord injury (ASCI). We tested this conclusion by analysis of 54 patients with ASCI; 25 patients were treated without MP before 1990 whereas 29 patients were treated with MP after 1990. Neurologic deficit was assessed regularly, in most cases daily. Motor and sensory scores on admission, and best results at one-half week (days 2 to 4), 1 week (days 6 to 10), 2 weeks (days 11 to 21), 1 month, and 2 months were noted for both groups. Motor assessment was recorded in 22 muscle segments on a scale of 0 (complete deficit) to 5 (normal); the range, thus, was 0 to 110. The 23 patients with closed injuries demonstrated no difference in improvement with or without MP. In contrast, MP was associated with impaired improvement in the patients with penetrating wounds; the 15 patients with no MP therapy had an admission motor score of 49, which increased by 6.9 at one-half week, whereas the 16 patients treated with MP had an admission motor score of 48, which decreased by 0.3 at one-half week (p = 0.03). The neural status seen by day 4 persisted throughout the next 2 months. Changes in sensation paralleled the changes in motor function. We conclude that MP therapy for penetrating ASCI may impair recovery of neurologic function.

Splenic reimplantation does not affect outcome in chronic canine model.

The effects of septic insult were compared in a canine model of splenic reimplantation. Sequential changes in hematologic, hepatic, and immunologic function were monitored biweekly in 18 dogs during 10 months after splenectomy, splenectomy with reimplantation, or sham operation. There was no significant difference in these measures between the two groups. At the end of the 10-month period, spleen scans with technetium (99Tc) labeled, heat-damaged RBCs were obtained on the reimplanted dogs. 99Tc scanning revealed no active splenic implants at 10 months. All dogs were then infected with intravenous Type III pneumococcus for 9 consecutive days. There were no measurable hematologic, hepatic, or immunologic differences between groups before or after the septic insult. These animals were then sacrificed for histologic analysis of the splenic reimplants. Reimplant histology showed active germinal centers, but the surrounding pulp was fibrotic and lymphocyte-depleted. Splenic reimplantation in this canine model yields no apparent benefit.

Antrectomy. A safe and effective bypass for unresectable pancreatic cancer.

BACKGROUND: Pancreatic cancer is most often diagnosed too late for curative resection. Operative therapy, therefore, involves relief of biliary obstruction and relief or prevention of gastric outlet obstruction. Previous studies show that gastrojejunostomy done either therapeutically or prophylactically often causes delayed gastric emptying. OBJECTIVE: To describe the results of antrectomy with Billroth II reconstruction (A/BII) as the palliative operation for gastric outlet obstruction. SUBJECTS: Fifty patients with unresectable pancreatic cancer underwent A/BII without vagotomy from 1987 through 1993. Of these patients, 42 underwent simultaneous biliary bypass; six had undergone biliary bypass from 3 weeks to 34 months previously; and two with cancer originating in the uncinate process had no biliary bypass. RESULTS: One 87-year-old patient died on day 12 of azotemia and pulmonary insufficiency. The other 49 patients were discharged tolerating an oral diet an average of 11.3 days (range, 5 to 29 days) after A/BII. The length of stay following A/BII was not related to the extent of disease or to preoperative weight loss but was increased in older patients. CONCLUSION: The A/BII is a safe and effective bypass in patients with unresectable pancreatic cancer.

Duodenal organ injury severity (OIS) and outcome.

The effect of organ injury severity on outcome was assessed in 101 patients treated for duodenal trauma. Most patients were men (89%) and victims of penetrating wounds (93%). Grade I is minor hematoma or incomplete perforation; Grade II is major hematoma or small complete perforation; Grade III is large perforation excluding ampulla; Grade IV is large perforation at ampulla; Grade V is duodenopancreatic crunch. The injuries were as follows: Grade I (5 patients), Grade II (31), Grade III (40), Grade IV (12), and Grade V (13). Fourteen patients exsanguinated from associated vessel injury; each had Grade IV or Grade V injury. All 36 patients with Grade I and Grade II injury had primary repair; the single death was due to liver necrosis. Most (31 patients) Grade III injuries and three Grade IV injuries were treated by primary repair alone; the three deaths were unrelated to the duodenal injury. Other major injuries were treated by duodenal exclusion (4 patients), duodenal diverticulization (6), or resection (4); the single death was unrelated to the duodenum. Primary closure is favored for minor injuries and most Grade III injuries. Severe injuries may require exclusion, diverticulization, or resection.

The technique of visceral packing: recommended management of difficult fascial closure in trauma patients.

Since 1986, we have cared for 17 patients whose abdomen could not be closed because of bowel edema and loss of abdominal wall compliance. These patients were managed by a technique of visceral packing with the intestines kept in place by a combination of rayon cloth, gauze packs, and retention sutures. This packing was changed in the operating room under general anesthesia until the edema was sufficiently resolved to allow for closure. Two patients died within 24 hours of operation from irreversible shock. The remaining 15 patients had their fascia successfully closed with an average of two additional anesthetics. There was one case of fasciitis associated with the development of an intra-abdominal abscess and one patient died of late sepsis. There was no early postoperative ventilatory compromise or acute oliguric renal failure. Other direct complications have been minor with no enterocutaneous fistulae, dehiscence, or incisional hernia. Visceral packing of posttraumatic abdominal wounds circumvents expected complications of intraperitoneal hypertension and enhances the chance for survival. Its ease and low morbidity also lends itself to a wide variety of other uses.

The vascular-interstitial pH gradient during and after hemorrhagic shock.

The interstitial fluid space (IFS) response to hemorrhagic shock (HS)-induced metabolic acidosis is reported. Prenodal skin lymph was used as a mirror of IFS changes. Twenty-three conditioned dogs had a reservoir HS insult followed by resuscitation with shed blood, crystalloid solution containing a total of 6.5 milliequivalents of sodium per kilogram of body weight and 250 milliliters of autologous banked blood. Prenodal skin lymph pH, oxygen tension (pO2), carbon dioxide tension (pCO2), bicarbonate level (HCO3) and flow rate measured before shock, during HS and in postresuscitation in 17 dogs in group 1 were compared with simultaneous samples of central venous blood. Peripheral venous values were not measured in dogs in group 1 to preclude any effects that local dissection might have on prenodal skin lymph. Six dogs in group 2 underwent the same HS and resuscitation model; the sequential changes in central mixed venous pH and lymphatic pH were compared with peripheral venous pH. HS caused metabolic acidosis; in group 1, the mixed venous pH decreased to 7.16 and in group 2, the peripheral venous pH decreased to 7.03. In contrast, the prenodal skin lymph pH in both groups was maintained at PS levels (7.51). Mixed venous pO2 decreased sharply with HS, whereas skin lymph pO2 was maintained. Maintained prenodal skin lymph pH and pO2 during HS-induced metabolic acidosis implies that the IFS undergoes stoichiometric changes. This facilitates the preferential adherence of highly charged proteins, like albumin, to the matrix to maintain cellular homeostasis.

Delayed pneumothorax after central venous access: a potential hazard.

Percutaneous central venous catheter access is common-place in surgical patients. Though several major complications of this procedure have been described, pneumothorax is the most common. Pneumothorax is routinely assessed by a chest X-ray within 2 hours after catheter placement. During a recent 6-month interval, the authors identified five patients with delayed onset and diagnosis of pneumothorax following percutaneous central venous access. All immediate post-insertion chest X-rays were normal; however, subsequent chest X-ray showed evidence of pneumothoraxes. The pneumothorax contributed to the death of one patient on positive pressure ventilation. A review of the literature revealed a total of 18 patients in the English literature with this complication. Although the incidence of delayed pneumothorax is low, it is, in some instances, life threatening, particularly in patients on positive pressure ventilation. A high index of suspicion is required to diagnosis and treat this reversible condition.

Management of the difficult abdominal closure.

Hemorrhagic shock and multiple trunk injuries, especially severe pelvic fracture, may cause massive swelling of intra-abdominal viscera and the abdominal wall, thereby precluding safe, primary abdominal wall closure. Primary closure, under tension in such patients, causes a multitude of problems including respiratory compromise, reduced cardiac output, oliguria, enterocutaneous fistulae, impaired abdominal wall nutrient blood supply, necrotizing fasciitis, evisceration, and death of the patient. Multiple methods have been described to aid the surgeon in circumventing these problems. The authors advocate the abdominal wall pack technique, which has the advantages of ease of implementation and a low rate of wound complications.

Splenic abscess associated with endocarditis.

BACKGROUND: Refractory or recurrent sepsis in patients with endocarditis may be from splenic abscess. The purpose of this review is to assess this relationship. METHODS: Of 564 patients treated for documented endocarditis between 1970 and 1990, splenic abscesses developed in 27 patients. The mean age of the 18 men and nine women was 37 years. Etiologic factors included street drugs, dental abscess, and rheumatic fever. Symptoms included fever, myalgia, chills, and dyspnea; the prodrome averaged 2 weeks. Typical signs were heart murmur, left lower-lobe infiltrate, and leukocytosis. Splenomegaly was found in three patients. All patients had valve lesions, which involved the aortic valve alone in 10 patients, the mitral valve alone in eight patients, and multiple valves in nine patients. RESULTS: A splenic defect on computed axial tomographic scan was diagnosed correctly as an abscess in 10 patients, was indeterminant in three patients, and was incorrectly called an infarct in four patients. Thirteen patients died. All 10 patients treated without splenectomy died, including five patients who underwent valvular replacement. In contrast, only three of 17 patients treated by splenectomy with (11 patients) or without (six patients) valvular surgery died. CONCLUSIONS: Splenic abscess often accompanies endocarditis. The diagnosis is suspected by refractory fever and confirmed by abdominal computed axial tomography scan. Splenectomy is warranted before or after valvular surgery, depending on the patient's clinical response to antibiotics.

The influence of an anesthetic regimen on patient care, outcome, and hospital charges.

The effects of the anesthetic regimen on patient care, outcome, and hospital charges were studied in 86 morbidly obese patients who underwent gastric reservoir reduction at two hospitals (A and B) in the Detroit Medical Center. At Hospital A, postoperative ventilation was routinely planned in 36 patients who received two intravenous lines, an arterial ine, and a Foley catheter. At Hospital B, postoperative ventilation was not routinely planned for in 50 patients who received one intravenous line and no Foley catheter or arterial line. For anesthesia, Hospital A routinely used isoflurane (0.98%) and N2O (53.0%) with little fentanyl (0.7 mg in 26 patients). Muscle relaxation with pancuronium (13.2 mg) was reversed in only five patients. In contrast, Hospital B patients used little isoflurane (0.4% in 14 patients),* more N2O (64.0%),* more fentanyl (1.3 mg),* and less pancuronium (9.7 mg)*; reversal with naloxone and pyridostigmine was routine. The operating room time was longer in Hospital A patients (5.0 vs 4.6 hours),* and they received significantly more intravenous fluids (6.2L vs 3.2L).* Routine postoperative ventilation in Hospital A patients led to a 46.5 hour intensive care unit stay and a 9.7 day postoperative stay. In contrast, routine anesthetic reversal allowed operating room extubation, patient self-transfer to the stretcher, and ambulation on the day of surgery in Hospital B where patients had a 1.7 hour recovery room stay and a 9.6 day postoperative stay. Total hospital charges in Hospital A patients averaged $14,524.00 due to the increased cost of the intensive care unit ($2,094.00) and support services versus $7,580.00* in Hospital B patients. All 86 patients survived.(ABSTRACT TRUNCATED AT 250 WORDS)

Fibrin gel limits intra-abdominal adhesion formation.

Autologous fibrin gel (FG) has recently been reported efficacious in hepatic injury; the effects of fibrin compounds on intra-abdominal adhesion formation is controversial. This study evaluated intra-abdominal adhesion formation in a rabbit devascularization model. Seventeen New Zealand rabbits were anesthetized and laparotomy was done. The uterine horns were abraded to punctate bleeding followed by bilateral uterine devascularization. Treatment consisted of 10 cc saline control (c) or FG applied to the uterine horns. Peritoneal lavage was done at 15 minutes for red blood cell (RBC) analysis. Autopsy was performed at 1 week. Adhesions were graded from grade 0 (no adhesions) to grade III (dense adhesions). Adhesion grading revealed no difference in average adhesion grade between FG and C with small bowel (1.0 +/- 1.3 vs 0.5 +/- 1.0); bladder (2.1 +/- 1.1 vs 2.4 +/- 1.2); or uterus (1.2 +/- vs 2.0 +/- 1.2). Adhesion grade was significantly less in FG compared to C for the colon and the abdominal incision (0.4 +/- 0.5 vs 1.7 +/- 1.1 and 1.2 +/- 1.1 vs 3.0 +/- 1.2; P less than 0.05 by t-test). There were no differences in lavage RBC count between FG and C (13.1 x 106 +/- 4.1 x 10(6) vs 8.7 x 106 +/- 3.2 x 10(6)). Fibrin gel significantly decreased incisional and colonic adhesions and reduced other abdominal adhesion formation by a nonhemostatic dependent mechanism.

Colloid oncotic pressure and body water dynamics in septic and injured patients.

Colloid oncotic pressure (COP) and fluid shifts were studied in 43 septic (SS) patients and 33 injured (HS) patients (ISS = 48.2). During maximal postresuscitation fluid retention, plasma volume (PV/RISA), red cell volume (RBC/51Cr), inulin space (ECF), and COP were measured. Interstitial space (IFS), PV/IFS ratio, and correlation coefficients (r) were calculated. A subgroup of 22 SS patients and 22 HS patients of equal study weight were also compared. Septic patients had greater IFS expansion (17.6 L vs. 11.5 L) than HS patients who, by inference, had more intracellular expansion. Expansion of IFS in SS patients correlated (r = -0.76, p less than 0.02) with reduced plasma COP; this was not seen in HS patients (r = -0.09, p less than 0.35). In contrast, plasma COP correlated (r = 0.72, p less than 0.001) with PV/RISA in HS patients but not in SS patients (r = 0.09, p greater than 0.35). We conclude: (1) SS patients with greater IFS expansion that correlates with reduced plasma COP likely have increased capillary permeability; and (2) HS patients with less IFS expansion that does not correlate with reduced plasma COP likely have maintained capillary permeability with altered IFS matrix configuration causing reduced protein exclusion.

Inhibition of fertility in rabbits by monoclonal antibodies against sperm.

Monoclonal antibodies were prepared against rabbit sperm antigens by fusing P3-X63-Ag8-653 mouse myeloma cells with lymphocytes from Balb/c mice immunized with Tergitol NP-40 detergent-solubilized rabbit epididymal sperm. Ascites fluid from mice injected with two of these hybridomas (8C4.1 and 8C10.5) was negative in immobilization and agglutination methods, however, acrosome positive on methanol fixed sperm and plasma membrane positive on unfixed sperm in indirect immunofluorescence. Insemination of female rabbits with the sperm treated with either of these monoclonal antibodies resulted in significant reduction in fertility as seen by the percentage of 9-day implants/corpora lutea ratio (8C4.1, 25.7%; 8C10.5, 1.9%; and control, 64.7%). Though the antibodies inhibited in vitro binding of the rabbit sperm with zonae pellucidae of rat ova, fertilization in vivo was not affected significantly. The antibodies did not demonstrate antiblastocyst activity by immunofluorescence. Both of these monoclonal antibodies appeared to recognize the same antigen by the SDS-PAGE/Protein Blot enzyme immunobinding procedure. The antigen was of testicular origin and had a molecular weight of approximately 63,000 daltons. It is concluded that these monoclonal antibodies which were organ specific, block post-fertilization fertility by inhibiting some step necessary for viable embryo formation.