PubMed Health⌕ Search

Biomedical subjects

L J Kaplan

Publications and source records attributed to L J Kaplan.

At least 19 recordsLinked to original sources
PubMed2001

Airway pressure release ventilation increases cardiac performance in patients with acute lung injury/adult respiratory distress syndrome.

BACKGROUND: The purpose of the present study is to determine whether airway pressure release ventilation (APRV) can safely enhance hemodynamics in patients with acute lung injury (ALI) and/or adult respiratory distress syndrome (ARDS), relative to pressure control ventilation (PCV). METHODS: Patients with severe acute lung injury or ARDS who were managed with inverse-ratio pressure control ventilation, neuromuscular blockade and a pulmonary artery catheter were switched to APRV. Hemodynamic performance, as well as pressor and sedative needs, was assessed after discontinuing neuromuscular blockade RESULTS: Mean age was 58 +/- 9 years (n = 12) and mean Lung Injury Score was 7.6 +/- 2.1. Temperature and arterial oxygen tension/fractional inspired oxygen (FiO2) were similar among the patients. Peak airway pressures fell from 38 +/- 3 for PCV to 25 +/- 3 cmH2O for APRV, and mean pressures fell from 18 +/- 3 for PCV to 12 +/- 2 cmH2O for APRV. Paralytic use and sedative use were significantly lower with APRV than with PCV. Pressor use decreased substantially with ARPV. Lactate levels remained normal, but decreased on APRV. Cardiac index rose from 3.2 +/- 0.4 for PCV to 4.6 +/- 0.3 l/min per m2 body surface area (BSA) for APRV, whereas oxygen delivery increased from 997 +/- 108 for PCV to 1409 +/- 146 ml/min for APRV, and central venous pressure declined from 18 +/- 4 for PCV to 12 +/- 4 cmH2O for APRV. Urine output increased from 0.83 +/- 0.1 for PCV to 0.96 +/- 0.12 ml/kg per hour for APRV. CONCLUSION: APRV may be used safely in patients with ALI/ARDS, and decreases the need for paralysis and sedation as compared with PCV-inverse ratio ventilation (IRV). APRV increases cardiac performance, with decreased pressor use and decreased airway pressure, in patients with ALI/ARDS.

Adult↗
PubMed2001

Laparoscopic repair of traumatic diaphragmatic injuries.

BACKGROUND: Laparoscopy has been proposed as a diagnostic and potentially therapeutic modality for penetrating diaphragmatic lacerations. The purpose of this study was to assess the technical feasibility and strength of various laparoscopic repairs of diaphragmatic injuries. METHODS: Swine underwent either open suture repair or laparoscopic repair by staple, suture, or patch technique of a 2-cm laceration to both the right and the left muscular or tendinous diaphragmatic leaflets. Six weeks after operation, diaphragms were harvested for either histologic analysis or bursting strength measurements. RESULTS: All methods of repair proved technically feasible. There was no significant difference in bursting strength measurements between treatment groups. Bursting was due to tissue failure either at or adjacent to the repair site. Histologic analysis confirmed healing of all specimens with the laparoscopic patch technique inciting less inflammation and greater fibroblastic proliferation than the other techniques. CONCLUSIONS: Laparoscopic repair of diaphragmatic lacerations can be accomplished using any of the currently available techniques. Laparoscopic stapling, suturing, or patch techniques all result in complete healing with a strong and durable repair. When selecting a particular technique, familiarity of the surgeon should be used as a guideline.

Animals↗
PubMed2001

The pharmacology of bimatoprost (Lumigan).

Bimatoprost (Lumigan) is a pharmacologically unique and highly efficacious ocular hypotensive agent. It appears to mimic the activity of a newly discovered family of fatty acid amides, termed prostamides. One biosynthetic route to the prostamides involves anandamide as the precursor. Bimatoprost pharmacology has been extensively characterized by binding and functional studies at more than 100 drug targets, which comprise a diverse variety of receptors, ion channels, and transporters. Bimatoprost exhibited no meaningful activity at receptors known to include antiglaucoma drug targets as follows: adenosine (A(1-3)), adrenergic (alpha(1), alpha(2), beta(1), beta(2)), cannabinoid (CB(1), CB(2)), dopamine (D(1-5)), muscarinic (M(1-5)), prostanoid (DP, EP(1-4), FP, IP, TP), and serotonin (5HT(1-7)). Bimatoprost does, however, exhibit potent inherent pharmacological activity in the feline iris sphincter preparation, which is prostamide-sensitive. Bimatoprost also resembles the prostamides in that it is a potent and highly efficacious ocular hypotensive agent. A single dose of bimatoprost markedly reduces intraocular pressure in dogs and laser-induced ocular hypertensive monkeys. Decreases in intraocular pressure are well maintained for at least 24 hr post-dose. Human studies have demonstrated that systemic exposure to bimatoprost is low and that accumulation does not occur. The sclera is the preferred route of accession to the eye. The high scleral permeability coefficient Papp is a likely contributing factor to the rapid onset and long-acting ocular hypotensive profile of bimatoprost.

Amides↗
PubMed2001

Start with a subjective assessment of skin temperature to identify hypoperfusion in intensive care unit patients.

OBJECTIVE: To determine whether physical examination alone or in combination with biochemical markers can accurately diagnose hypoperfusion. METHODS: Data from 264 consecutive surgical intensive care unit patients were collected by two intensivists and included extremity temperature, vital signs, arterial lactate, arterial blood gases, hemoglobin, and pulmonary artery catheter values with derived indices. Days of data were divided into data collected from patients with cool extremities (cool skin temperature [CST] group) versus warm extremities (warm skin temperature [WST] group). Values are means +/- SD. Comparisons between groups were made by two-tailed unpaired t test; significance was assumed for p < or = 0.05. RESULTS: There were 328 days of observations in the CST group versus 439 in the WST group. There were no differences (p > 0.05) between CST and WST data with regard to heart rate (107 +/- 14 vs. 99 +/- 19 beats/min), systolic blood pressure (118 +/- 24 vs. 127 +/- 28 mm Hg), diastolic blood pressure (57 +/- 14 vs. 62 +/- 15 mm Hg), pulmonary artery occlusion pressure (14 +/- 6 vs. 16 +/- 5 mm Hg), Fio2 (0.48 +/- 0.7 vs. 0.45 +/- 0.2), hemoglobin (8.8 +/- 1.6 vs. 9.3 +/- 1.3 g/dL), Pco2 (44.3 +/- 11.8 vs. 40.7 +/- 9.2 mm Hg), or Po2 (96.4 +/- 12.6 vs. 103.8 +/- 22.2 mm Hg). However, cardiac output (5.3 +/- 2.2 vs. 8.2 +/- 2.6 L/min), cardiac index (2.9 +/- 1.2 vs. 4.3 +/- 1.2 L/min/m2), pH (7.32 +/- 0.2 vs. 7.39 +/- 0.07), TCO2 (19.5 +/- 3.1 vs. 25.1 +/- 4.8 mEq/L), and Svo2 (60.2 +/- 4.4% vs. 68.2 +/- 7.8%) were all significantly lower (p < 0.05) in CST patients compared with WST patients. By comparison, lactate (4.7 +/- 1.5 vs. 2.2 +/- 1.6 mmol/L, p < 0.05) was significantly elevated in patients with cool extremities. CONCLUSION: Combining physical examination with serum bicarbonate and arterial lactate identifies patients with hypoperfusion as defined by low Svo2 and cardiac index. Hypoperfusion may occur despite supranormal cardiac indices. Patients with cool extremities and elevated lactate levels may benefit from a pulmonary artery catheter to guide but not initiate therapy.

Algorithms↗
PubMed2000

Can preclinical medical students be integrated into the continuing medical education process by instructing prehospital care providers?

OBJECTIVE: To develop a model introducing medical students (MS) to the continuing medical education (CME) process while simultaneously developing a curriculum to enhance the relevant surgical anatomy knowledge base of the advanced prehospital care provider. METHODS: A CME curriculum for teaching human anatomy was developed and approved by the governing state agencies for prehospital education. The curriculum focused on structures relevant to the prehospital care of the trauma patient in a case based format using common scenarios presented by surgery and emergency medicine faculty. Five year-one medical students who completed gross anatomy served as teaching staff and were given a structures list one week prior to the CME course. Human cadavers were prosected by the medical students prior to the CME program under the guidance of the surgical faculty. Course attendees and medical student staff were anonymously surveyed at the end of the program (rating scale 1 = low to 5 = high). Prehospital providers were given a multiple-choice posttest and surveyed at 3 months after the course with regard to applicability to their current practice. Data are means +/- SD. RESULTS: Nineteen licensed practicing paramedics attended the course. All of the paramedics scored above the 85% passing cutoff on the posttest (95. 6% +/- 6.2%). Instructor qualities were rated highly (4.62 +/- 0.49) with no instructor rating less than a 3. MS believed themselves well prepared to teach (5 +/- 0), and spent 2 +/- 0.81 hours in preparation. They were only infrequently faced with questions they were not well prepared to answer (1.25 +/- 0.5) and would uniformly participate in CME offerings in the future (5 +/- 0). The CME program improved the MS view of CME (3 +/- 0), prehospital education (3 +/- 1.4), and the surgeon as educator (3.25 +/- 1.5). At 3 months, the paramedics felt that the CME program significantly impacted the care they rendered (4.37 +/- 0.76), and improved their understanding of injury complexes (4.53 +/- 0.61), and resuscitation (4.26 +/- 0. 73). The cadaver course was uniformly recommended to coworkers (5 +/- 0). CONCLUSIONS: This model provided prehospital care providers direct contact with clinically relevant human anatomy, enhanced their understanding of pertinent anatomy, and positively impacted their patient care. MS were introduced to the CME process and found it to be one with which they would become reinvolved. Furthermore, the MS felt prepared to present human anatomy, met the expectations of the course attendees, improved their understanding of prehospital education, and positively altered their perception of the surgeon as an educator. This process holds promise as both a model for prehospital education and as a tool for integrating MS into the role of allied health educator early in their career.

Anatomy↗
PubMed2000

Atlanto-occipital dislocation: an unusual lethal airbag injury.

Airbag-induced injury fatality is increasing in frequency. We present the case of a 6-year-old passenger who sustained a fatal atlanto-occipital dislocation associated with airbag deployment in a low-speed motor vehicle crash. The current literature regarding airbag fatalities and methods to ameliorate airbag-induced injury are reviewed.

Accidents, Traffic↗
PubMed2000

Replacement of the carboxylic acid group of prostaglandin f(2alpha) with a hydroxyl or methoxy substituent provides biologically unique compounds.

Replacement of the carboxylic acid group of PGF(2alpha) with the non-acidic substituents hydroxyl (-OH) or methoxy (-OCH(3)) resulted in an unexpected activity profile. Although PGF(2alpha) 1-OH and PGF(2alpha) 1-OCH(3) exhibited potent contractile effects similar to 17-phenyl PGF(2alpha) in the cat lung parenchymal preparation, they were approximately 1000 times less potent than 17-phenyl PGF(2alpha) in stimulating recombinant feline and human FP receptors. In human dermal fibroblasts and Swiss 3T3 cells PGF(2alpha) 1-OH and PGF(2alpha) 1-OCH(3) produced no Ca(2+) signal until a 1 microM concentration was exceeded. Pretreatment of Swiss 3T3 cells with either 1 microM PGF(2alpha) 1-OH or PGF(2alpha) 1-OCH(3) did not attenuate Ca(2+) signal responses produced by PGF(2alpha) or fluprostenol. In the rat uterus, PGF(2alpha) 1-OH was about two orders of magnitude less potent than 17-phenyl PGF(2alpha) whereas PGF(2alpha) 1-OCH(3) produced only a minimal effect. Radioligand binding studies on cat lung parenchymal plasma membrane preparations suggested that the cat lung parenchyma does not contain a homogeneous population of receptors that equally respond to PGF(2alpha)1-OH, PGF(2alpha)1-OCH(3), and classical FP receptor agonists. Studies on smooth muscle preparations and cells containing DP, EP(1), EP(2), EP(3), EP(4), IP, and TP receptors indicated that the activity of PGF(2alpha) 1-OH and PGF(2alpha) 1-OCH(3) could not be ascribed to interaction with these receptors. The potent effects of PGF(2alpha) 1-OH and PGF(2alpha) 1-OCH(3) on the cat lung parenchyma are difficult to describe in terms of interaction with the FP or any other known prostanoid receptor.

3T3 Cells↗
PubMed1999

Traumatic hematuria in patients with polycystic kidney disease.

Autosomal dominant polycystic kidney disease (PKD) is the most prevalent hereditary disorder in this country and a common cause of chronic renal failure. Patients frequently present with hematuria as the initial manifestation of PKD. We describe a patient with gross hematuria after blunt trauma who was found to have previously undiagnosed PKD. We review present diagnostic and treatment modalities and suggest potential management strategies for surgeons caring for patients presenting with traumatic hematuria and PKD.

Adult↗
PubMed1997

Improved emergency department efficiency with a three-tier trauma triage system.

This pilot study was carried out to determine whether converting from a two-tier to a three-tier in-hospital trauma triage system improves the efficiency of emergency department (ED) care and minimizes inappropriate triage. Patients at an urban, Level 1 trauma centre were triaged using either a two-tier (months 1-3; n = 197) or three-tier (months 4-6; n = 240) trauma response system. Patients were assessed for triage type, age, sex, injury severity score, Glasgow coma score, post-ED disposition, total ED time, survival, complication rate, probability of survival and unexpected death. Comparisons were made by ANOVA table analysis; significance was assumed for p < 0.05. Two-tier (n = 197) and three-tier patients (n = 240) were matched with respect to mean age, sex, mean injury severity score, mean Glasgow coma score, post-ED disposition, survival and probability of survival. Two-tier patients were triaged to give 20% alerts [criteria = physiological derangement (PD) and/or injury mechanism (MOI)] and 80% consults; three-tier patients were triaged as 20% category I (criteria = PD), 18% category II (criteria = MOI) and 62% consults. Total ED time decreased from two-tier (3.98 +/- 2.81 h) to three-tier triage (3.53 +/- 2.14 h, p = 0.001). There was no difference between two-tier alert and three-tier category I times (2.09 +/- 1.64 vs. 1.95 +/- 1.75 h; p = 0.72). Category II patients (3.28 +/- 1.98 h; p = 0.009) spent less time in the ED than did two-tier consults (4.36 +/- 2.65 h). The mean ED three-tier consult time significantly decreased as well (3.95 +/- 2.42 h, p = 0.008 vs. two-tier consult). Complications per patient were unchanged from two-tier to three-tier triage (0.17 +/- 0.52 vs. 0.12 +/- 0.48; p = 0.15). Under-triage (5%) and over-triage (7.5%) were minimal under three-tier triage. It is concluded that using a three-tier triage system results in an increase in the early involvement of the trauma service while decreasing emergency department time and minimizing over-triage.

Adult↗
PubMed1996

Reversible injury: creatinine kinase recovery restores bioenergetics and function.

In postischemia hearts, cytoplasmic creatinine kinase (CK) inactivation resulting from toxic oxygen metabolite injury may lead to bioenergetic and mechanical dysfunction. This study determines the relationship between CK activity, mechanical function, and bioenergetics during reperfusion (RP) after a reversible ischemic injury. Rat hearts pretreated after 12 hr without (CTRL) or with myristic acid (MA) underwent 10 min global, 37 degrees C ischemia followed by 10 or 40 min RP while developed pressure (DP) was monitored. Catalase and CK were assayed at preischemia. CK was also assayed at end ischemia and 10 and 40 min RP. 31 P nuclear magnetic resonance spectra assessed changes in phosphocreatinine (PCr) and adenosine triphosphate (ATP) concentration. Preischemic DP was 95 +/- 5 mm Hg. CTRL DP returned to 84 +/- 3 by RP10 and 88 +/- 6 by RP40 while MA hearts recovered fully by RP10 (90 +/- 2). Preischemic catalase activity was significantly increased in MA hearts (1217 +/- 36 U/g left ventricular tissue (LV) vs 1007 +/- 40 U/g LV, P < 0.01, MA vs CTRL). CTRL CK activity fell from 1870 +/- 75 to 1103 +/- 11 U/g LV at RP10, but rose to 1272 +/- 13 by RP40 (P < 0.01, RP10 vs RP40). MA hearts lost no CK activity during RP. By RP10, CTRL PCr/ATP ratio was elevated to 2.2 +/- 0.2 (P < 0.001) from a preischemic level of 1.7 +/- 0.4 and normalized by RP40, while MA hearts had a normal PCr/ATP throughout RP. Reversible RP injury transiently depresses mechanical function. Cytoplasmic CK damage during RP impairs PCr utilization, leading to a PCr overshoot. Functional recovery and metabolic recovery follow return of CK activity. Increased endogenous catalase preserves CK during RP, resulting in normal function and bioenergetics.

Adenosine Triphosphate↗
PubMed1996

Gastric bezoar following penetrating abdominal injury. Diagnosis and endoscopic therapy.

We present a patient who developed a gastric bezoar following extensive penetrating abdominal trauma. Bezoar pathogenesis, diagnosis, and endoscopic therapy are highlighted. Additionally, alternative therapeutic modalities are explored with a review of the literature. Combination endoscopic lavage fragmentation/extraction presents a safe method of bezoar resolution.

Abdominal Injuries↗
PubMed1996

Thoracic compartment syndrome.

Presented is a case of a thoracic gunshot wound resulting in descending thoracic aortic and biventricular cardiac injuries. Successful management of these wounds allowed the development of an unusual and previously undescribed complication of thoracic trauma--thoracic compartment syndrome. The clinical features, therapy, and potential sequelae of thoracic compartment syndrome are presented with a review of the literature.

Adolescent↗
PubMed1996

Percutaneous drainage of recurrent pneumothoraces and pneumatoceles.

Thoracic trauma victims commonly sustain visceral pleural injury with resultant pneumothorax. These injuries usually respond to standard tube thoracostomy decompression and drainage. However, a subset of these patients develop recurrent and/or loculated pneumothoraces or pneumatoceles that are not readily accessible by tube thoracostomy. Percutaneous catheter drainage of these collections provides a safe and reliable method of management in critically ill patients.

Adult↗
PubMed1996

Technique of sacral hernia repair.

After sacrectomy, a hernial defect may develop through the pelvic floor at the reconstructed sacral bed. This complication has not previously been described. We describe a technique for repair of such a defect using a prosthetic patch. Accurate and safe repair of this hernia requires correct preoperative diagnosis and planning, including a thorough knowledge of pelvic floor anatomy.

Colonic Diseases↗
PubMed1996

The American Academy of Dermatology's response to managed care and capitation.

Managed care is an important part of the health care delivery system; consequently, dermatologists are seeking information about various managed care plans and are joining them. Managed care can encompass a variety of different systems, including preferred provider organizations, health maintenance organizations, and individual practice associations. They all provide health care services to enrolled members through a defined network of providers who are given the responsibility to provide quality medical care while controlling use and access to specialists. Many members of the American Academy of Dermatology (AAD) respond in surveys that education in various aspects of managed care is an area of great importance to them.

Capitation Fee↗
PubMed1995

The phosphocreatine overshoot occurs independent of myocardial work.

Although the exact mechanism(s) responsible for the phosphocreatine/ATP overshoot have not been completely elucidated, our data demonstrate that the overshoot does not stem from reduced myocardial work, and consequently, reduced utilization of phosphocreatine (PCr). Additionally, we highlight a basic difference in the physiologic responses of skeletal and cardial muscle to work demands. By understanding the bioenergetic derangements which accompany reperfusion injury, one may hope to better salvage post-ischemic myocardium.

Adenosine Triphosphate↗
PubMed1994

Ischemic preconditioning preserves end-ischemic ATP, enhancing functional recovery and coronary flow during reperfusion.

The mechanisms by which ischemic preconditioning (IPC) protects against reperfusion (RP) injury are unknown. The purpose of this study was to relate IPC to postischemic mechanical function, vascular reactivity, and bioenergetics. Isolated perfused rat hearts were randomized to two groups. Control (CTRL) hearts underwent 25 min of global, 37 degrees C ischemia and 40 min RP. IPC hearts underwent 2.5 min ischemia and 10 min RP followed by 25 min ischemia and 40 min RP (RP40). Left ventricular developed pressure (DP) and coronary flow were continuously measured. 31P NMR spectra determined phosphocreatine and ATP concentrations in parallel hearts every 5 min. Results are means +/- SEM; n = 6/group. Significance was assumed for P < 0.05 by paired (within groups) and unpaired (between groups) t test. CTRL heart DP recovered to 35 +/- 4% of preischemic (PI) DP by RP40 (P < 0.001), while IPC heart DP reached 99 +/- 4% (P = NS vs PI; P < 0.001 vs CTRL). CTRL coronary flow recovered to only 75 +/- 3% of PI (P < 0.001) by RP40. IPC coronary flow exceeded baseline during RP (RP40 = 118 +/- 3%, P < 0.001 vs CTRL; P < 0.05 vs PI). After 25 min ischemia, CTRL heart ATP fell to 40 +/- 4% of PI (P < 0.001) while the IPC group fell to only 60 +/- 4% (P < 0.05 IPC vs CTRL; P < 0.001 vs PI). IPC preserves more end-ischemic ATP compared to CTRL hearts with a resultant improvement in mechanical function during reperfusion. Only preconditioned hearts preserve the adaptive mechanism(s) responsible for postischemic vasodilatation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗