Biomedical subjects
Publications and source records attributed to T J Iberti.
Toxic shock syndrome is an uncommon disease associated with staphylococcal infections. Although most frequently reported in menstruating women and associated with tampon use, toxic shock syndrome has been described following many types of surgical procedures. In this report we describe a case of toxic shock syndrome occurring in a previously healthy young man after elective surgery for a pilonidal cyst.
Explore the source record for details and available documents.
BACKGROUND AND METHODS: It is hypothesized that pentoxifylline may be beneficial during shock states by improving tissue oxygenation. To test this hypothesis, we examined the effect of pentoxifylline on hemodynamics, oxygen delivery (DO2), and tissue metabolism during severe hemorrhagic shock. We conducted a placebo-controlled, randomized trial using anesthetized, mechanically ventilated dogs in hemorrhagic shock maintained at a mean arterial pressure of 45 to 50 mm Hg. Six animals were treated with a 10-mg/kg bolus of iv pentoxifylline followed by a continuous infusion at 5 mg/kg.hr. The controls consisted of six animals treated with saline. RESULTS: There were no significant differences between the groups before treatment. During 150 mins of posttreatment, repeated measurements of the control and pentoxifylline groups showed no significant differences in heart rate (HR), cardiac output, systemic and pulmonary vascular resistances, DO2, or blood lactate concentration (repeated-measures analysis of variance). CONCLUSIONS: In this acute, nonresuscitated, canine hemorrhagic shock model, pentoxifylline did not act as a vasodilator, or have any significant effect on HR, cardiac output, oxygen transport, or lactic acidosis.
Explore the source record for details and available documents.
We administered a 31-question multiple-choice examination to 496 physicians practicing in 13 medical facilities in the United States and Canada to assess their knowledge and understanding of the use of the pulmonary artery catheter and interpretation of data derived from it. The mean test score was 20.7 (67% correct), with an SD of 5.4 and a range of 6 to 31 (19% to 100%). Mean scores varied independently by training, frequency of use of pulmonary artery catheter data in patient treatment, frequency of inserting a pulmonary artery catheter, and whether the respondent's hospital was a primary medical school affiliate. Given the variability in physician understanding of the pulmonary artery catheter, we believe that credentialing policies should be reevaluated and that consideration should be given to restricting its use to individuals with documented competency.
The anion gap is commonly used as a screening test for the presence of lactic acidosis. Analysis of the distribution of anion gaps for 56 adult surgical ICU patients with peak blood lactate levels greater than or equal to 2.5 mmol/L showed the anion gap to be an insensitive screen for elevated lactate in a critically ill, hospitalized population. All patients (11/11) with a peak lactate greater than or equal to 10 mmol/L had an anion gap greater than or equal to 16 mmol/L; however, 50% (6/12) of patients with lactates between 5.0 and 9.9 mmol/L and 79% (26/33) of those with lactates between 2.5 and 4.9 mmol/L had anion gaps less than 16 mmol/L. Hyperlactatemia was associated with considerable mortality at all levels: 100% among patients with lactate levels greater than or equal to 10 mmol/L, 75% between 5.0 and 9.9 mmol/L, and 36.4% between 2.5 and 4.9 mmol/L. Acidosis (pH less than 7.30) did not significantly alter mortality by lactate level. The observation that, for 57% of patients in this study, an elevated lactate level was not accompanied by an elevated anion gap suggests that hyperlactatemia should be included in the differential diagnosis of nonanion gap acidosis.
Explore the source record for details and available documents.
Histamine H2-receptor antagonists (H2RAs) often are administered to intensive care unit patients in an attempt to reduce gastric acidity and to prevent stress-related mucosal damage. These agents have an extremely low overall incidence and severity of adverse reactions; however, hemodynamically significant hypotension has been noted. Clinical studies with rapidly administered intravenous cimetidine in critically ill patients have demonstrated a depression in blood pressure in up to 75 percent of patients. Ranitidine, also studied in this setting, does not appear to induce similar hemodynamic changes. The newer H2RAs, famotidine and nizatidine, have not been evaluated in critically ill patients.
Explore the source record for details and available documents.
The determination of intra-abdominal pressures (IAP) may be useful in many clinical situations. The authors recently demonstrated in the canine model a close correlation between actual IAP and the bladder pressure measurements obtained from a transurethral catheter. The purpose of this study was to clinically validate this technique. The authors studied 16 patients, and compared IAP in three positions (supine, with compressions, and semi-erect) utilizing both direct intraperitoneal pressure monitoring and the pressure obtained with a transurethral bladder catheter. Their results demonstrated a linear relationship between the two methods described, with a mean r value of 0.95 in the supine and semi-erect positions, and 0.99 with abdominal compressions (P less than 0.0001). The authors conclude that transurethral monitoring of bladder pressure offers a safe, simple, and highly accurate method for evaluating IAP at the bedside. Studies evaluating the indication for its use in the operating room and intensive care settings appear warranted.
Explore the source record for details and available documents.
Gangrenous bowel after aortic reconstructive surgery is associated with an exceptionally high mortality rate. Numerous diagnostic modalities have not reduced the incidence of death from infarcted bowel because of their lack of specificity and the associated delays in diagnosis. Recently, we have begun to use bedside laparoscopy to identify suspected gangrenous bowel in critically ill postoperative patients. Herein we describe a case of small-bowel infarction after aortic aneurysm surgery that was identified by the use of a laparoscope, with successful surgical repair and return of bowel function. Postoperative gangrenous bowel, standard diagnostic tests used in this setting, and the use and indications for beside laparoscopy are reviewed.
The hemodynamic effects of intravenous ranitidine were studied in a prospective double-blind fashion in postoperative intensive care unit patients to determine if this H2 blocker produced the same transient fall in mean arterial pressure and systemic vascular resistance known to occur with cimetidine infusion. We found no statistically significant hemodynamic changes from baseline associated with infusion of 50 mg ranitidine over a 5-minute period. The different chemical ring structure of ranitidine and its effect on H2 vascular and cardiac receptors may account for these observations.
We evaluated the use of percutaneous endoscopic gastrostomy in 30 ICU patients. There was a 14% incidence of minor complications, no major complications, and no mortality. We conclude that percutaneous endoscopic gastrostomy is a useful alternative to operative gastrostomy in the ICU patient.
We studied the use of sodium bicarbonate administration in a canine model of hemorrhagic shock to determine its effect on hemodynamics, arterial and venous blood gases, respiratory gases, and blood lactate levels. Thirteen dogs were anesthetized, paralyzed, mechanically ventilated, and hemodynamically monitored. Hypotension was induced and maintained at a mean arterial pressure of 40 to 45 mm Hg using controlled hemorrhage and reinfusion. After 2.5 h of shock, the dogs were randomized into two groups: one group (n = 6) received NaCl infusion; the other (n = 7) received sodium bicarbonate (1 mEq/kg followed by a continuous infusion of 2.5 mEq/kg.h for 2.5 h). CO2 production was increased in the alkali group, but there was no statistically significant difference between groups in any measured hemodynamic, blood gas, or respiratory gas variable. These included heart rate, BP, cardiac output, arterial and venous pH, CO2 production, and bicarbonate levels. Blood lactate levels, however, in the bicarbonate treated animals were significantly (p less than .01) higher than in the group treated with NaCl alone (10.1 +/- 3.2 vs. 5.1 +/- 1.2 mEq/L). These results are similar to the effects of bicarbonate found in other models of lactic acidosis, and suggest that bicarbonate therapy may have limited usefulness in the treatment of lactic acidosis.
We studied the use of the head-down tilt position (Trendelenburg) in elderly postoperative patients in the intensive care unit to determine its effect upon cardiac and pulmonary function. Twenty-two patients (mean age 68.4 years) were placed in a 12 degrees head-down tilt position for 15 minutes. No deterioration was shown in any measured cardiac parameter; mean arterial pressure, cardiac index, and right and left ventricular stroke work increased significantly (P less than .05). Further, there were no observed changes in arterial or venous oxygenation, or in venous admixture. Because of the uncertain effect of the head-down tilt position upon cerebral blood flow, the routine use of this position is not recommended for the treatment of hypotension or during cardiopulmonary resuscitation. The results of this study, however, show that the cardiopulmonary effects are well tolerated if the position is required, as during central venous access procedures.
Explore the source record for details and available documents.
Explore the source record for details and available documents.