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S R Shackford

Publications and source records attributed to S R Shackford.

144 records · Page 8Linked to original sources
PubMed1986

Immunomodulating drugs increase resistance against sepsis in traumatized mice.

Immune suppression occurs frequently after major injury and undoubtedly contributes to infection and mortality in trauma patients. Prevention of such suppression may lead to decreased infection and improved survival in trauma patients surviving the immediate insult of injury. Suppressor-cell activation appears to play a key role in immune suppression after major injury. For several years we have studied the effects on immune functions after injury of various drugs which have been shown in the immunologic literature to have inhibitory effects on suppressor cell populations. H2-antagonists may inhibit suppressor cell activation by blocking surface H2-receptors, which are present in higher numbers on suppressor cells than on helper cells. Prostaglandin inhibitors may block the multiple immune suppressive effects of prostaglandins, particularly PGE2. Immunological studies suggest that low-dose cyclophosphamide selectively inhibits the proliferation of suppressor T cells. Our previous work suggested that such drugs preserve cell-mediated immune functions after injury. In experiments reported here, we utilized a standard hindlimb crush injury and amputation in mice, followed in 24 hrs by polymicrobial septic challenge using cecal ligation and 23-gauge needle puncture (CLP). Nontraumatized (control) mice had a 36.2% mortality after CLP; when crush injury/amputation was followed by CLP in 24 hrs the mortality rose to 63.8% (p less than 0.0035). When mice were given 24 hrs before crush/amputation: cimetidine, an H2-antagonist (10 mg/kg/day); ibuprofen, a prostaglandin blocker (5 mg/kg/day); or cyclophosphamide (2.5 mg/kg/day), and a second dose on the day of trauma, with CLP 24 hrs later, subsequent mortality was not different from the mortality in nontraumatized, control mice (p less than 0.0035).(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvants, Immunologic↗
PubMed1986

The effect of regionalization upon the quality of trauma care as assessed by concurrent audit before and after institution of a trauma system: a preliminary report.

To assess the need for a trauma system in San Diego County, a concurrent audit of trauma care was performed by an independent consultant in 1982. During the study period from 15 March through 15 June 1982, 591 consecutive major trauma victims (MTV) were collected by the 30 participating hospitals. All medical records, including autopsy reports, were audited for the timeliness and appropriateness of diagnosis and definitive care. Deaths were classified as being not preventable, potentially salvageable, or preventable. A trauma system subsequently became functional on 1 August 1984, with five adult centers and one pediatric center. A Medical Audit Committee composed of physicians and nurses from designated and nondesignated hospitals was organized to perform a monthly concurrent audit of trauma care. Between 1 August and 31 December 1984, 1,366 MTV were triaged to trauma centers. The care of MTV was considered suboptimal in 32% of patients before regionalization, compared to 4.2% after regionalization (p less than 0.01). Preventable deaths occurred in 13.6% of fatalities occurring before implementation of a trauma system, compared to 2.7% after implementation (p less than 0.01). Regionalization of trauma care significantly reduced delays, inadequate care, and preventable deaths due to trauma.

Adolescent↗
PubMed1986

Late septic complications in adults following splenectomy for trauma: a prospective analysis in 144 patients.

One hundred forty-four patients were prospectively followed through our Asplenic Registry for the development of late septic complications following splenectomy for trauma. There were 114 males and 30 females with a mean age of 28.6 years. The total time of followup was 8,810 patient months with a mean followup of 61 months (range, 12-144 months). Indications for splenectomy were blunt trauma, 111 patients; penetrating trauma, six patients; and intra-operative injury, 27 patients. During the followup to date, 15 late major septic complications requiring hospitalization have occurred in 13 patients (9%). Fulminant pneumococcal sepsis resulted in the death of a 27-year-old male, 3 years after splenectomy. Septicemia occurred in four patients, pneumonia in five, abscess in two, infection of a prosthetic heart valve in one, meningitis in one, and fever of unknown origin in one. All but two of these infections were due to encapsulated organisms. Minor septic complications occurred in 44 patients (30%), and consisted of infections which required outpatient medical care. Major late septic complications occurred more frequently following incidental splenectomy than following splenectomy for blunt or penetrating trauma (18.5% and 5.9% respectively; p less than 0.05). The mortality from major septic complications in this series (7%) is lower than previously reported by other investigators (30-80%). Our data suggest that adults undergoing splenectomy for trauma are at an increased risk of developing late major septic complications. This risk is significant enough to warrant attempts at splenic salvage, especially when injury is incidental to an elective operative procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Abscess↗
PubMed1986

Comparison of isotonic and hypertonic fluids in resuscitation from hypovolemic shock.

Hypertonic electrolyte solutions provide effective fluids for resuscitation of burn patients and concurrent replacement of hemorrhage. Infusion of mannitol has also been advocated as a means of increasing cardiac output in acutely ill patients. Pigs which were bled to one-third of their blood volume were used in this random study of resuscitation with Ringer's lactate solution (RL), hypertonic saline solution (HSL) and RL with mannitol added (HMR) to give the same osmolality as HSL. Smaller volumes of the hyposmolar solution than of RL restored blood pressure and cardiac output. RL and HSL restored and maintained cardiac output more effectively than HMR. At 24 hours, HSL maintained blood pressure most effectively.

Animals↗
PubMed1984

Cricothyroidotomy for long-term tracheal access. A prospective analysis of morbidity and mortality in 76 patients.

Cricothyroidotomy for long-term tracheal access was prospectively studied in 76 critically ill patients. Thirty patients (39%) survived and 46 (61%) died. Mean duration of follow-up computed in all survivors was 8.5 months. Postmortem examination of the airway was performed in 85% of the nonsurvivors. Five patients (7%) had major complications including one death, subglottic stenosis in two adolescent patients, reversible subglottic granulation with partial obstruction in one patient, and tracheomalacia in one patient. Minor complications occurred in 23 (30%) survivors. Eleven (28%) of the nonsurvivors examined post mortem had airway pathology, including ulceration, hemorrhage and abscess at the stoma or cuff site, subglottic erosion, and mucosal separation. There were no significant differences in any of the parameters studied between the group with and the group without airway pathology. The morbidity and mortality of cricothyroidotomy in adults are similar to that reported for tracheostomy. However, cricothyroidotomy should be avoided in children and adolescents because of the risk of subglottic stenosis.

Adolescent↗
PubMed1984

Crystalloid versus colloid in fluid resuscitation of patients with severe pulmonary insufficiency.

Forty-six patients with severe pulmonary insufficiency were prospectively studied to compare the effects of resuscitation with either crystalloid or colloid. By random number, 26 patients received RL and 20 patients received 5 per cent ALB to maintain hemodynamic stability. Groups were comparable with respect to the cause of pulmonary insufficiency, age and sex. For the duration of the study and at 48 hours, there was no statistically significant difference between groups with respect to the following: cardiac index, colloid osmotic pressure (COP), pulmonary capillary wedge pressure (PCWP), COP-PCWP gradient, right and left ventricular stroke work indices, and amount of constant positive airway pressure required for treatment. Both groups had a significant improvement in intrapulmonary shunt (Qs/Qt) after 24 hours of treatment. The Qs/Qt in the ALB group was significantly lower than the RL group at the termination of the study, but this did not affect outcome. The RL group required more fluid than the ALB group, but the difference was not statistically significant. No clinical advantage was found for either solution in this study.

Adult↗
PubMed1983

Hypertonic sodium lactate versus lactated ringer's solution for intravenous fluid therapy in operations on the abdominal aorta.

Fifty-eight patients who were to undergo aortic reconstruction were prospectively randomized into two groups to compare the effects of perioperative fluid replacement with isotonic and hypertonic crystalloid solutions. Blood loss was replaced with packed red blood cells, and additional fluid was given as either Ringer's lactate solution (RL, 130 mEq sodium/L, 274 mOsm/L) or a hypertonic balanced salt solution (HSL, 250 mEq sodium/L, 514 mOsm/L). Fluid was administered to maintain the cardiac filling pressure within 3 torr of the preoperative level and the cardiac output (CO) at or above the preoperative level. The groups were similar with respect to age, preexisting disease, duration of operation, and operative blood loss. During the operation, the RL group required 9.5 +/- 0.8 L of fluid, whereas the HSL group required 4.5 +/- 0.3 L (P less than 0.001). Pulmonary, cardiac, and renal functions were adequately maintained in both groups. There were no significant differences between the groups with regard to CO, urine output, or creatinine clearance during the operation and early postoperative period. Postoperatively, the intrapulmonary shunt was 20 +/- 1% in the RL group and it was 16 +/- 1% in the HSL group (P less than 0.05). The amount of sodium infused and the cumulative sodium balance at the completion of the study period were similar in both groups. Serum sodium and osmolarity were significantly greater in the HSL group (P less than 0.001), reaching a maximum of 151 +/- 1 mEq/L and 305 +/- 2 mOsm/L, respectively. Two patients in the HSL group had a persistent elevation in serum osmolarity (greater than 320 mOsm/L) during operation, for which they received RL for the balance of the resuscitation. There were no complications that could be attributed to the hypertonicity of the solution. HSL is effective for resuscitation of patients with extracellular fluid deficit and is safe provided that the serum sodium and osmolarity are monitored during periods of large volume administration.

Aorta, Abdominal↗
PubMed1982

Serum oncotic pressure and oncotic-hydrostatic pressure differences in critically ill patients.

The possible influence of serum colloid oncotic pressure (COP) and the gradient between COP and pulmonary capillary wedge pressure (COP-PCWP) on respiratory insufficiency and survival was studied prospectively in 77 critically ill surgical patients by daily simultaneous measurements of COP, PCWP, and intrapulmonary shunt (Qs/Qt). Mean ages of survivors (N = 51) and nonsurvivors (n = 26) were 46 +/- 3 years (survivors) and 58 +/- 4 years (nonsurvivors), respectively (p less than 0.01). Lowest value of COP was similar in survivors (15 +/- 1 torr) and in nonsurvivors (14 +/- 1 torr). Lowest value of COP-PCWP in survivors was 3 +/- 1 torr and -1 +/- 2 torr in nonsurvivors (p less than 0.05). The difference in COP-PCWP was secondary to a significantly greater PCWP in nonsurvivors (16 +/- 1 torr) than in survivors (12 +/- 1 torr) (p less than 0.01). For each patient, Qs/Qt measured at the time of lowest measured COP was not significantly different between survivors and nonsurvivors (0.18 +/- 0.01) in survivors and 0.20 +/- 0.01 in nonsurvivors) and measured at lowest COP-PCWP (0.18 +/- 0.01 in survivors, and 0.21 +/- 0.01 in nonsurvivors). No correlation was found between either lowest COP or lowest COP-PCWP and Qs/Qt. Progressive respiratory insufficiency was not a dominant factor in determining respiratory insufficiency was not a dominant factor in determining mortality. These data suggest that COP alone is not a critical factor in determining either survival or respiratory insufficiency as measured by Qs/Qt in critically ill surgical patients.

Adult↗
PubMed1981

Whole blood versus packed-cell transfusions: a physiologic comparison.

Twenty-eight patients undergoing major aortic reconstructions were prospectively randomized into two groups to compare blood replacement with either whole blood (WB) or packed cells (PRBC). Cardiac index (CI), pulmonary capillary wedge pressure (PCWP), intrapulmonary shunt (Qs/Qt), serum colloid osmotic pressure (COP), platelets, prothrombin time (PT), partial thromboplastin time (PTT), and fibrinogen were measured before operation, during operation, and for three days after operation. The postoperative CI increased significantly in both groups from preoperative value, but was not significantly different between the groups. In the PRBC group, there was a significant decrease in postoperative COP and COP-PCWP gradient from preoperative value. This did not occur in the WB group. There was no significant difference between groups in postoperative Qs/Qt, nor was there any evidence of clinical or radiographic pulmonary dysfunction. Both groups manifested a prolongation of the PT and PTT immediately after operation, but these returned to normal without intervention by the first day after operation. It is felt that blood replacement with reconstituted packed red cells can provide effective volume replacement without producing coagulopathy. The decreases observed in COP and COP-PCWP gradient do not result in physiologic or clinical evidence of significant pulmonary dysfunction.

Blood Coagulation↗
PubMed1981

Complications of the flow-directed pulmonary artery catheter: A prospective analysis in 219 patients.

In order to determine and analyze the complication rate of the insertion and maintenance of the balloon-tipped, flow-directed pulmonary artery catheter (PAC), the authors prospectively studied the use of 320 catheters in 219 critically ill patients. Mean patient age was 53 +/- 1 years, and 36% had a history of cardiovascular disease. Mean duration of catheterization averaged 76 +/- 3 h. Major complications occurred in 3% of catheterizations. These included six pneumothoraces; three arrhythmias requiring treatment, one of which was fatal; and one subclavian vein thrombosis. Site complications occurred more frequently in catheters maintained longer than 72 h. These findings suggest that, when indicated in the care of critically ill patients, the properly placed and maintained PAC has an acceptably low morbidity and mortality rate, particularly when used for 72 h or less.

Arrhythmias, Cardiac↗
PubMed1981

Selective use of ventilator therapy in flail chest injury.

We have prospectively treated 36 patients with flail chest using a treatment protocol for limited use of mechanical ventilation. Age of the patients ranged from 6 months to 83 years. Patients were divided into three groups dependent upon their clinical presentation and need for respiratory support: Group I patients had severe pulmonary dysfunction-tachypnea, dyspnea, arterial PO2 less than or equal to 60 torr, arterial PCO2 greater than or equal to 50 torr or shunt fraction greater than or equal to 25%. Group II patients had no pulmonary dysfunction but did require temporary respirator support for an associated injury. Group III patients had no pulmonary dysfunction. Thirteen patients were assigned to Group I. They required respiratory support for an average of 10.5 days; 11 of the 13 had complications, and there were two deaths in this group resulting from a combination of respiratory failure and myocardial infarction. Seven patients were assigned to Group II. six patients were extubated immediately postoperatively; one patient with a head injury was hyperventilated for 48 hours to reduce intracranial pressure and then extubated. Sixteen patients were assigned to Group III. Fifteen required no ventilatory support. One 83-year-old man developed pneumonia and was mechanically ventilated for 31 days. Early effective pain control and chest physiotherapy were critical to success and were used in all patients. Increase in respiratory rate, fall in tidal volume or vital capacity, and increased pain were used as criteria for administration of analgesia. Nonventilatory therapy of flail chest reduces morbidity, mortality, and hospital cost.

Adolescent↗
PubMed1981

Early extubation versus prophylactic ventilation in the high risk patient: a comparison of postoperative management in the prevention of respiratory complications.

To evaluate whether prophylactic ventilation during the early postoperative period diminishes pulmonary complications, 35 high risk, elderly patients undergoing major, elective abdominal aortic reconstruction were prospectively randomized into either an early extubation group or a prophylactic ventilation group. The 17 patients assigned to the prophylactic ventilation group received mechanical ventilation by assist/control mode until 8 a.m. of the first postoperative day. The 17 patients assigned to the early extubation group were extubated after the operation as soon as they could maintain a pH of 7.35, with a spontaneous respiratory rate of less than 30. Preoperative measurements of functional residual capacity, intrapulmonary shunt, and oxygen delivery were compared to similar measurements during the initial two postoperative days. There were no significant differences between the groups with respect to age, length of operation, duration of anesthesia, operative blood loss, intraoperative fluid administration, or number of intraoperative transfusions. Patients in the prophylactic ventilation group were ventilated for an average of 18.3 +/- 0.5 hours. Patients in the early extubation group were ventilated for an average of 3.3 +/- 0.5 hours (p < 0.0005). No patient in either group required reintubation. Intrapulmonary shunt and oxygen delivery were not significantly different between the groups at any time during the study period. There was no mortality or significant morbidity in either group. These findings suggest that in high risk surgical patients, prophylactic ventilation, per se, may not diminish respiratory complications or improve gas exchange.

Aged↗
PubMed1981

Evaluation of splenorrhaphy: a grading system for splenic trauma.

Since April 1977, we have used splenorrhaphy as the procedure of choice for splenic trauma. To evaluate the efficacy of this procedure, we graded splenic injury based upon the extent of splenic repair in 77 patients with blunt abdominal trauma. This grading system is as follows: Grade 1-capsular treatment (five patients); Grade 2-capsular or parenchymal injuries requiring topical hemostatic agents (13 patients); Grade 3-parenchymal injuries requiring suture repair (nine patients); Grade 4-parenchymal injuries requiring partial splenic resection (seven patients); Grade 5-total splenic devascularization or uncontrollable bleeding from the splenic pedicle requiring splenectomy (43 patients). Twenty-nine patients had associated orthopedic injuries, and 42 patients had associated intra-abdominal or thoracic injuries. Mean operative time was 130 +/- 10 minutes. Operative time increased with severity of associated intra-abdominal injuries. Mean operative transfusion requirement was 500 +/- 100 cc of packed red blood cells. Transfusion requirements were not related to the severity of splenic injury. Twenty-three patients developed complications. Pancreatitis occurred in three patients, atelectasis of pneumonitis in eight patients, ten developed wound infections, and two patients required reoperation for small-bowel obstruction. Complication rates were not related to the degree of splenic injury. The grading system described herein provides a framework for sound clinical judgment and comparison of results in the management of splenic injuries.

Abdominal Injuries↗
PubMed1980

Typhlitis: a treatable complication of acute leukemia therapy.

Heretofore, pseudomembranous enterocolitis, or more specifically typhlitis, occurring as a complication of the cytotoxic chemotherapy of acute leukemia has nearly always resulted in a fatal outcome. Recent surgical literature states that if cecitis is found as a consequence of therapy for leukemia, the surgeon should refrain from operating because standard procedures, including hemicolectomy, have not improved survival. This paper reports two patients with acute typhlitis resulting from induction therapy of acute leukemia with cytosine arabinoside and hydroxydaunorubicin. Both patients underwent subtotal colectomy, while their marrows were aplastic from therapy, and survived their surgery. Both are living and well in maintained remission, 1 year from surgery. We review the pathogenesis of this disorder and discuss its clinical, x-ray, and laboratory features. Close oncologic/surgical teamwork is stressed as the patient is followed closely into the time frame when the decision is made whether to operate. Factors contributing to this decision are discussed. Preoperative recommendations are made in order to bring the patient into a state of physiologic stability. The operative procedure is described along with the postoperative complications encountered. We strongly recommend that laparotomy be considered in selected patients with typhlitis occurring as a complication of treated leukemia.

Adolescent↗
PubMed1978

The significance of chest wall injury in the diagnosis of traumatic aneurysms of the thoracic aorta.

It has been suggested that patients sustaining blunt chest injury severe enough to result insignificant bony injury to the thorax may have traumatic aneurysms of the thoracic aorta in the absence of th widened mediastinum on plain film. To test the validity of this hypothesis, we performed aortograms on 14 patients with severe blunt chest injury but an otherwise normal chese X-ray. None of these patients was found to have an aortic injury. By contrast, of 21 patients with severe chest injury and a widened mediastinum who underwent thoracic aortography eight were found to have traumatic aneurysms of the thoracic aorta. These results suggest that in the absence of a widened mediastinum, severe chest wall injury is not an indication for aortography.

Adolescent↗
PubMed1976

The management of flail chest. A comparison of ventilatory and nonventilatory treatment.

Retrospective analysis of forty-two consecutive patients with flail chest injuries admitted to the Trauma Research Unit of the Naval Regional Medical Center, San Deigo from June 1972 to July 1975 compared ventilatory and nonventilatory management. The actual need for ventilatory support in these patients was determined by analyzing their records for evidence of significant pulmonary dysfunction. This allowed division of patients into three groups: "appropriately" ventilated; "inappropriately" ventilated; and nonventilated. Admission PO2 in the "appropriately" ventilated patients was significantly lower than in the other two groups because the former were admitted with respiratory distress and hypoxemia. Significantly more complications occurred in the ventilated groups than in the nonventilated. Treatment-associated complications were more frequent in the ventilated groups. Because of these findings, we belive that mechanical ventilation should be used in the treatment of flail chest injuries only for significant pulmonary dysfunction and not for the purpose of stabilizing the chest wall. If respiratory support is required, it should be discontinued when normal gas exchange has been restored.

Adolescent↗