The predictive value of frozen section in the diagnosis of parotid tumors

A total of 38 patients with frozen section slides who underwent parotidectomy from January 1980 to December 1993 were retrieved from the Department of Pathology. The permanent section slides of the resected specimens were used as the gold standard. The frozen section and permanent section slides were reviewed by two independent pathologists and were labeled either as benign or malignant. If malignant, the tumor grade was determined as either high grade or low grade. Kappas correlation of agreement was used to determine inter-observer variability. Of the 38 slides, 16 were correctly labeled as malignant and 20 as benign. One slide was incorrectly labeled as malignant and 1 as benign. Sensitivity was 94.1 and specificity was 95.2 percent. The prevalence of malignant parotid tumors was 44.7 per cent, with a positive predictive value of 94.1 per cent and a negative predictive value of 95.2 per cent. Kappa statistic for the permanent section was 100 per cent, and 85 per cent for the frozen section. Tumor grading revealed that only 35.2 per cent were labeled correctly as high grade or low grade. This study showed that frozen section could reliably diagnose a malignant parotid tumor but could not reliably determine tumor grade. (Author)

The center for disease control-national nosocomial infection surveillance (CDC-NNIS) surgical patient risk index score and surgical site infections at UERMMMC

The study retrospectively reviewed 1,029 general surgery operations performed from September 1, 1991 to May 31, 1993 to find out the association between the occurrence of surgical site infection (SSI) and the Centers for Disease Control-National Nosocomial Infection Surveillance (CDC-AWS) surgical patient risk index scores. The index assigned 1 point for each of 3 risk factors: 1) American Society of Anesthesiologists (ASA) preoperative assessment class 3, 4 or 5; 2) an operational classified as either contaminated or dirty-infected; 3) an operation with a duration longer than a specified increased with increasing contamination (p=0.000) as well as increasing index scores (p=0.000). Looking at operations within the same category of contamination, SSI rates also increased with increasing scores among clean operations (p=0.944), clean-contaminated operations (p=0.000), contaminated operations (p=0.559), and dirty operations. SSI rates in this hospital series were compared to the 44-hospital CDC-NNIS report.

The diabetic foot: An analysis of predictive factors for amputation

A retrospective study was undertaken on 103 diabetic patients with foot ulcers who were confined at the UERM Memorial Medical Center from January 1988 to June 1991 with the aim of determining clinical and laboratory criteria which are useful in predicting the need for amputation. Patients were divided into two groups according to treatment modality: Group A, debridement (58 patients) and Group B, amputation (45 patients). Nineteen variables chosen from the patients demographic characteristics, clinical histories and evaluation, and laboratory work-up were reviewed, evaluated, and processed using the normal approximation statistics and logistic regression to obtain a resulting set of predictors. Osteomyelitis, leukocytosis, decreased or absent peripheral pulses, systolic hypertension and smoking history were the five variables found to be significantly associated with the need for an ablative surgical procedure. These quantitated variables are entered into the computed logistic equation to obtain a score which will enable us to determine the appropriate therapeutic intervention tailored to the individuals risk status. If the computed value is greater than or equal to 7, amputation should be the course of action. If the computed value is less than or equal to 3, conservative treatment is advocated. If the value obtained is between 3 and 7, the patient is considered a borderline case and proper management will have to depend on the judgment of the surgeon. With this scoring system as a guide, a definitive operation can be performed at an early stage to prevent the burden of multiple operations and the accompanying high morbidity and post-operative mortality rates.

Mandatory celiotomy for penetrating abdominal stab wounds: An analysis of 483 cases

It has been suggested in a number of studies that penetrating abdominal stab wounds may be managed conservatively although only a few local studies support this claim. This study reviews experience based on 483 patients, who underwent celiotomy for a single penetrating abdominal stab wound inflicted by a single bladed knife from Jan. 1989 to June 1991. The cases were divided into two (2) groups, those who underwent celiotomy with indications and those who underwent celiotomy without indications. Tabulation of operative findings according to the location of the stab wound in the nine (9) regions of the anterior abdomen showed that 89% of all patients with indications for surgery had significant injury. In the group who underwent celiotomy without indications, 78% had positive findings. The data for groups A and B stratified into the nine regions did not show any significant difference in the frequency of abdominal injury except in the right lumbar, left lumbar, left iliac and umbilical region. In these last four regions, the frequency of abdominal injury in the group with indications is statistically higher than in the group without indications. Therefore, a trial of observation in these regions is therefore acceptable in the absence of indications for celiotomy.