Biomedical subjects

W F McManus

Publications and source records attributed to W F McManus.

At least 37 records · Page 2Linked to original sources

PubMed1992

Resting energy expenditure in patients with thermal injuries.

Resting energy expenditures (REE) were measured using indirect calorimetric techniques in 62 patients with burn injuries admitted during 1987 to 1989 and compared with similar measurements made during 1972 to 1973. Energy requirements were related to burn size in both populations, but were greater in the earlier population. In the present study, data from some patients were obtained using a canopy system and from others during mechanical ventilation and were analyzed separately. The regression of REE on burn size was linear for the canopy measurements (r = 0.724) and for the ventilator measurements (r = 0.579). REE data were corrected for the expected basal metabolic rate (BMR) for each patient, with appropriate adjustment for age and sex. The regression of REE per BMR on burn size was linear (r = 0.724), differing from the curvilinear relationship found during 1972 to 1973. These data suggest a change in postburn energy requirements, probably related to differences in patient management. Predictive equations based on older data can be expected to overestimate energy requirements in patients receiving modern burn therapy.

Adolescent↗

PubMed1991

Fungal burn wound infection. A 10-year experience.

To evaluate our experience with fungal burn wound infection, we performed a 10-year review for comparison with our experience with bacterial burn wound infection. During the study period, a marked decline occurred in bacterial wound infection but not in fungal wound infection. Patients with either bacterial or fungal burn wound infection had massive injury, with burn size averaging greater than 50% of the total body surface area. Factors that appear to have markedly reduced bacterial burn wound infection, including patient isolation, topical chemotherapeutic agents, and burn wound excision, do not appear to have had a similar effect on fungal wound infection. The mechanism of spread and colonization of fungi, and the lack of effective topical chemotherapeutic antifungal agents, may explain in part our findings.

Adult↗

PubMed1991

Effects of granulocyte-macrophage colony-stimulating factor in burn patients.

We studied the effects of granulocyte-macrophage colony-stimulating factor in burn patients. Serial measurements of granulocyte oxidative function were obtained in treated patients and in a group of controls matched for age and total burn size. The administration of granulocyte-macrophage colony-stimulating factor resulted in a 50% increase in mean leukocyte counts. Both groups showed significant baseline increases in granulocytic cytosolic oxidative function. Treated patients showed normal stimulated cytosolic oxidative function, which was significantly depressed compared with that of untreated patients. Myeloperoxidase activity was increased in treated patients during the first postburn week but then declined to normal levels. Untreated patients had a significant increase in myeloperoxidase activity for the first 3 weeks following injury. Untreated patients exhibited a significant decrease in superoxide activity during the second 3 weeks following injury. Treated patients demonstrated normal superoxide activity.

Acridines↗

PubMed1991

Prophylactic use of high-frequency percussive ventilation in patients with inhalation injury.

Death and the incidence of pneumonia are significantly increased in burn patients with inhalation injury, despite application of conventional ventilatory support techniques. The effect of high-frequency percussive ventilation on mortality rate, incidence of pulmonary infection, and barotrauma were studied in 54 burn patients with documented inhalation injury admitted between March 1987 and September 1990 as compared to an historic cohort treated between 1980 and 1984. All patients satisfied clinical criteria for mechanical ventilation. High-frequency percussive ventilation was initiated within 24 hours of intubation. The patients' mean age and burn size were 32.2 years and 47.8%, respectively (ranges, 15 to 88 years; 0% to 90%). The mean number of ventilator days was 15.3 +/- 16.7 (range, 1 to 150 days), with 26% of patients ventilated for more than 2 weeks. Fourteen patients (25.9%) developed pneumonia compared to an historic frequency of 45.8% (p less than 0.005). Mortality rate was 18.5% (10 patients) with an expected historic number of deaths of 23 (95% confidence limits of 17 to 28 deaths). The documented improvement in survival rate and decrease in the incidence of pneumonia in patients treated with prophylactic high-frequency ventilation (HFV), as compared to a cohort of patients treated in the 7 years before the trial, indicates the importance of small airway patency in the pathogenesis of inhalation injury sequelae and supports further use and evaluation of HFV.

Adolescent↗

PubMed1989

Excision of the burn wound in patients with large burns.

The known major determinants of survival for patients with burn injury are age, burn size, inhalation injury, and infection. The clinical courses of 210 patients with burns of 30% of the body surface or greater treated from Jan 1, 1983, through Dec 31, 1985, were reviewed to determine whether excision of the burn wound could be identified as a factor in survival after massive burn injury. The predominant site of infection changed from the burn wound to the lung, with pneumonia being the most common bacterial infection in patients whose wounds were treated as described. Effective topical control of bacterial proliferation and excision of the burn wound have resulted in replacement of invasive bacterial wound infection by nonbacterial burn wound infection. The apparent advantages of excision, particularly in large burns, may reflect only patient selection, since only those patients who are considered to be physiologically stable and able to tolerate the physiologic stress of excision are considered for operation.

Adolescent↗

PubMed1989

What's in a name? Is methicillin-resistant Staphylococcus aureus just another S aureus when treated with vancomycin?

Methicillin-resistant Staphylococcus aureus (MRSA) strains, principally resistant to penicillinase-resistant penicillins and aminoglycosides, are increasingly common hospital isolates. We have examined the significance of MRSA colonization and infection in 1100 consecutively admitted, seriously burned patients in whom vancomycin was used to treat all staphylococcal infections. Colonization with S aureus (SA) was identified in 658 patients, in 319 of whom MRSA colonization was identified. Two hundred fifty-three SA infections occurred in 178 patients; of these infections, 58% were pulmonic and 38% were bacteremic. Methicillin-resistant SA infections occurred in 58 of the SA-infected patients. A severity index, based on multiple-regression analysis of mortality as a function of burn size and age in the study population, was used to estimate expected mortality. We demonstrated no measurable increase in mortality attributable to MRSA in this population of burned, SA-infected patients. The results question the clinical and economic value of added control practices, such as closing of units, refusal of transfer or admission, added isolation, treatment of carriers, furlough of colonized staff, and other expensive measures that are specifically directed at prevention of MRSA infections in critical care areas.

Burns↗

PubMed1989

High-frequency percussive ventilation in patients with inhalation injury.

Inhalation injury complicated by bacterial pneumonia is now one of the primary causes of morbidity and mortality in patients with thermal injury. We have investigated the use of high-frequency percussive ventilation (HFPV) as a means of ventilatory support for these patients. We propose that high-frequency ventilation may decrease the incidence of pulmonary infection following inhalation injury and decrease the incidence of iatrogenic barotrauma caused by conventional ventilation. High-frequency ventilation was instituted initially as salvage therapy in a group of five patients. In each case, normocapnia or arterial pO2 saturation of greater than 90% on a FIO2 of 60% or less was achieved with high-frequency ventilation but not with conventional ventilation. A second group of ten patients was prospectively entered into a study on the use of HFPV in patients with inhalation injury. One patient was removed from the study, and one patient was unable to be ventilated because of severely noncompliant lungs. Eight patients with a mean age of 29 years and a mean burn size of 38% of the total body surface completed the protocol. All patients survived, two developed pneumonia, and one developed subcutaneous emphysema. These results suggest that HFPV is effective in the treatment of patients with severe inhalation injury.

Adult↗

PubMed1989

Relationship of transfusion and infection in a burn population.

The relationship between the number of red blood cell transfusions and major infectious complications was evaluated in 594 thermal injury patients admitted between 1982 and 1986 who had burns over 10% or more of total body surface area and survived more than 10 days. The mean age of this group was 32.9 years, with a mean burn size of 36% of total body surface area; 83% were male. Of the 594 patients, 23.7% died and 38.7% had documented inhalation injury. The mean number of red blood cell transfusions received was 19.7, with a range of 0 to 201. Two hundred fourteen patients (36%) had major infectious complications, defined as pneumonia or invasive burn wound infection. A cross-tabulation of predicted mortality, number of transfusions, and infectious complications revealed a significant positive correlation between transfusion number and infectious complications in patients with predicted mortalities between 10 and 70%. Per cent total burn, patient age, presence of inhalation injury, and number of transfusions were identified by discriminant function analysis as significant variables (p less than 0.05) in discriminating between patients with and without infections (85% accuracy). Logistic regression analysis confirmed the above findings, showing a relationship between the number of transfusions received and infectious morbidity which was independent of age or burn size, but no significant relationship between number of transfusions and mortality.

Adolescent↗

PubMed1988

Chemical burns.

In chemical skin injuries, reduction of the time of exposure to the causative agent and recognition of systemic toxicity are necessary to lessen the severity of the insult, reduce morbidity, and maximize survival. During a 17-year period (1969 through 1985), 87 (2.1%) of the 4,212 burned patients admitted to the U.S. Army Institute of Surgical Research sustained chemical burns. Twelve of 87 patients died (13.8%). White phosphorous, the most common causative agent, produced cutaneous injury in 49 patients. Acids (13 patients), alkalies (ten patients), and organic solvents (five patients) were the other common causes of injury. Initial treatment consisted of water lavage. Later wound management was carried out with topical antibiotic therapy and excision and grafting as necessary. Systemic toxicity due to phenol, nitrate, and formate absorption occurred, as did acute tubular necrosis following copper sulfate treatment of white phosphorus burns. Inhalation injury occurred in five patients. A decrease in hospital stay for chemically injured patients was observed. To minimize chemical injury, clothing should be removed promptly and water lavage begun. Systemic toxicity and inhalation injury are rare but often severe and increase mortality.

Adolescent↗

PubMed1988

Heterotopic bone formation in burned patients.

Heterotopic bone formation about joints and in soft tissues is known to cause joint immobilization and permanent physical impairment in burned patients. Despite aggressive physical therapy aimed at prevention, heterotopic bone formation still occurs in a small percentage of patients. Prolonged immobilization in concert with trauma or burn about the involved joint is recognized as being responsible for this heterotopic bone formation. Specifically, immobilization of extremities, particularly the elbow and upper extremity, should be minimized by early grafting for preservation of function. As burn therapy has enabled increasing numbers of patients to survive extensive burns, it is imperative that preservation of function not be ignored and that attention be directed at improved function early in the postburn course.

Adult↗

PubMed1988

Fluid resuscitation of infants and children with massive thermal injury.

Age-related limitations of physiologic reserve in burned children make adequacy of intravenous fluid resuscitation critical. To quantify fluid requirements, the medical records of all children admitted to the Army Institute of Surgical Research from 1980 to 1986 whose weight was 25 kilograms or less and burn size was 25% or greater were reviewed to quantify fluid requirements. Forty-three children ranging in age from 1.5-108 months (means 26 +/- 22 m), with 25-89% total body surface burned (TBSB) (means 41.7% +/- 14.6%), met inclusion criteria. The average total volume of fluid received during the first 24 hours was 6.3 +/- 2.2 cc/kg/% TBSB. The net volume of resuscitation fluid, total volume less the calculated maintenance fluid requirements, was 3.91 +/- 2.2 cc/kg/% TBSB. Univariate analysis and linear regression of independent variables including age, weight, per cent full thickness, and inhalation injury revealed each had no significant influence on the volume of resuscitation. We recommend supplying maintenance volume and initiating burn resuscitation at 3 cc/kg/% TBSB.

Body Surface Area↗

PubMed1988

Suppurative chondritis: its incidence, prevention, and treatment in burn patients.

A retrospective study of 317 cases of suppurative otochondritis occurring in a population of 4794 burned patients successively admitted to one institution between 1967 and 1984 is presented. During the study interval, the incidence of the disease decreased from 20 percent to less than 3 percent in patients with burns of one or both ears. The bacterial species associated with chondritis, principally Pseudomonas aeruginosa and Staphylococcus species, did not change. Patients admitted later than the second postburn day exhibited a significantly greater incidence of chondritis. The crucial factors in prevention of this complication appear to be avoidance of pressure on burned ears and topical chemotherapeutic control of local Pseudomonas infection. Systemic antibiotic prophylaxis did not appear to influence the incidence in the studied population. Several approaches to clinical management of suppurative chondritis are reviewed.

Adult↗

PubMed1987

Comparison of quantitative microbiology and histopathology in divided burn-wound biopsy specimens.

We examined the association between quantitative microbiologic results and histopathologic findings in divided biopsy specimens from 200 burned patients. Microbiologic counts were determined as log10 colony-forming units per gram of disrupted tissue. Histopathologic results were scored on a scale of 1 to 6, values of 4 or greater indicating microbial invasion of viable tissue. Agreement of 96.1% was found between negative cultures, arbitrarily identified as those with fewer than 5 logs/g, and histologic absence of invasive infection. In sharp contrast, however, histologic invasion occurred in only 36% of specimens with positive cultures. Though low tissue counts are essentially synonymous with negative histologic findings, quantitative microbiology is not a diagnostic substitute for histologic examination, since high tissue counts quite commonly do not indicate invasion. The principal value of quantitative burn-wound biopsies is the demonstration of predominant burn-wound flora.

Adolescent↗

PubMed1987

Clinical trial of imipenem/cilastatin in severely burned and infected patients.

Imipenem/cilastatin was examined for safety and efficacy in a population of 20 seriously burned patients with acute bacterial infections. The study was made up of 18 males and two females with an average age of 38 years and average burn size of 52 per cent of the total body surface area. Inhalation injury was present in 14 patients. The infections treated included 16 pulmonary, two urinary tract, one wound and one bacteremia. Treatment was clinically successful in 13 patients; five patients had no improvement and the clinical response could not be determined in two in whom multisystem organ failure preceded the treated infection. All of the clinical failures were in the pulmonary infection group. No serious toxicity or side effects were noted. No patient died while receiving the drug or as a consequence of known failure of the drug. Microbiologic success was noted in 12. Resistant organisms developed in eight of whom five were in the clinical failure group. Pseudomonas aeruginosa resistant to imipenem/cilastatin was isolated from seven patients and occurred at an average of 3.6 days after treatment was begun.

Adult↗

PubMed1986

Effects of environment on infection in burn patients.

Burn patients in an early cohort (n = 173) treated in an intensive care ward without separate enclosures were compared with a later cohort (n = 213) treated in a renovated unit with separate bed enclosures. The number of patients developing infection was significantly reduced in the late group. Observed mortality was compared with mortality predicted on the basis of burn size and age alone. Reduction in observed compared with predicted mortality, inapparent in the early group, was seen in the late group and was restricted to the subgroup of patients with predicted mortality of 25% to 75%, in which the observed mortality of 28.3% was less than the predicted mortality of 48.7%. The incidence of infected patients was reduced from 58.1% in the early cohort to 30.4% in the late cohort. In comparison of the early cohort with the late cohort, the overall proportion of patients with bacteremia was reduced from 20.1% to 9.4%, while the incidences of both pneumonia and burn wound invasion remained unchanged. Providencia and Pseudomonas species, endemic in the early cohort, were eliminated in the late cohort. Reduction of infection by environmental manipulation in burn patients was possible and was associated with improved survival.

Adult↗

PubMed1985

Lightning injury with survival in five patients.

Of a total of 4,153 admissions, five patients with lightning-associated injuries were admitted to a burn center during a 15-year period, 1969 through 1983. In these patients, the burned portion of the total body surface ranged from 3% to 29% (average, 16%), and all survived. The associated injuries and complications in these lightning-strike victims and a review of treatment guidelines are presented.

Adolescent↗

PubMed1985

Microbial colonization in a new intensive care burn unit. A prospective cohort study.

Renovation of an existing intensive care burn facility required closure for ten months. An interim eight-bed open intensive care ward (B) was established in a burn convalescence ward. The renovated unit (A) contained nine single-bed intensive care rooms and seven intermediate-level care beds in four rooms. Patients admitted to unit A were treated as a cohort. The first 25 admissions to unit A and the last 25 admissions to ward B meeting the inclusion criteria were compared. Microbial colonization was monitored by a fixed protocol of admission and multiple weekly sputum, wound, stool, and urine cultures. During intensive care, both cohorts exhibited the same incidence of gram-negative wound, sputum, and urine colonization. Occurrence of antibiotic-resistant organisms was the same. No evidence of bacterial cross-contamination was observed between A and B. A continuation of Providencia stuartii and Pseudomonas aeruginosa (type 15) endemics occurred in B. The collected data demonstrate that the A cohort was colonized with new, similar but distinct gram-negative organisms and indicate that cohort separation may be a practical way of eliminating endemic resistant gram-negative organisms from burn units.

Adult↗

PubMed1985

Twenty-five year review of Pseudomonas aeruginosa bacteremia in a burn center.

The incidence of Pseudomonas aeruginosa bacteremia was examined in 5,882 burn patients consecutively admitted over a 25-year period to one burn center. The population examined had an average burn size of 33.8% of the body surface and an average age of 26.3 years. Pseudomonas aeruginosa bacteremia occurred in 540 patients. These patients had an average burn size of 54.2% and average age of 28 years. Mortality was 77%. Bacteremia with other organisms occurred during hospitalization of all but 128 of the 540 patients. Comparison of predicted mortality based on burn size and age to observed mortality showed Pseudomonas aeruginosa bacteremia to be associated with a 28% increase in mortality. Examination of mortality as a function of time showed no significant change over the 25-year period. The incidence of Pseudomonas aeruginosa colonization and infection was examined in 400 recently admitted burn patients. Colonization occurred in 107 and 34 infections were recorded in 27 of the colonized patients.

Adult↗