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M D Klein

Publications and source records attributed to M D Klein.

At least 19 recordsLinked to original sources
PubMed1999

Cardiac tamponade caused by serous pericardial effusion in patients on extracorporeal membrane oxygenation.

PURPOSE: Extracorporeal membrane oxygenation (ECMO) has been successful in the treatment of critically ill children; however, its use has been accompanied by a broad range of complications. The authors describe the presentation, clinical course, treatment, and outcome of 4 patients on ECMO in whom pericardial tamponade developed caused by a serous effusion. METHODS: A retrospective review of patients placed on ECMO at our institution from 1993 to 1997 was performed. The case histories of 4 patients in whom pericardial tamponade developed caused by a serous effusion were reviewed in detail. RESULTS: The first patient presented with hypotension while on venovenous (VV) ECMO. The hypotension improved with fluid resuscitation. The patient was converted from (VV) to venoarterial (VA) ECMO when hypotension recurred. After a third episode of hypotension, a narrow pulse pressure was noted, and echocardiography results confirmed a pericardial effusion. The diagnosis was recognized earlier in the course of the subsequent 3 patients. All 4 patients were treated with aspiration of serous fluid from the pericardium with an over-the-needle plastic catheter that was left in place. More than 1 aspiration was required in all cases. All 4 patients survived. CONCLUSIONS: The authors have identified a group of ECMO patients with pericardial tamponade caused by serous effusion with good response to treatment. A high index of suspicion and early echocardiography is warranted to confirm the diagnosis in a patient with hypotension on ECMO.

Cardiac Tamponade↗
PubMed1999

Muscle and nerve biopsy in the evaluation of neuromuscular disorders: the surgeon's perspective.

BACKGROUND/PURPOSE: A muscle biopsy frequently is requested by the neurologist evaluating a child with neuromuscular symptoms. However, there are no reports discussing the preoperative evaluation for, and diagnostic yield of, this procedure. The authors reviewed our experience over a 10-year period to obtain these data. METHODS: The records of 153 patients who underwent muscle biopsy were reviewed with particular attention to the cardiology evaluation, the pathology report, and any resultant change in diagnosis and treatment of the child. RESULTS: All 153 specimens contained adequate tissue for complete histological analysis. Preoperative cardiology consults were obtained in 82% of the children, with abnormalities found in 9%. Severe cardiac dysfunction was found in three children, all of whom had a previously diagnosed cardiomyopathy or dysrhythmia. No pathological abnormality was found in 41% of the muscle biopsy specimens, and nonspecific pathological findings were described in 23%. A specific diagnosis was made in 36%. Only 19% of the children had their treatment changed by the results of the muscle biopsy. CONCLUSIONS: Muscle biopsies can be performed safely without routine preoperative cardiac evaluation. A specific diagnosis, however, may be made in less than half of the patients with a change in therapy available for even fewer.

Biopsy↗
PubMed1997

The prison patient.

Explore the source record for details and available documents.

Adrenergic beta-Antagonists↗
PubMed1997

Evaluation of contrast media for bronchography.

BACKGROUND: Bronchography is occasionally needed for the evaluation and management of some congenital pulmonary anomalies as well as some acquired diseases, usually of the tracheo- bronchial tree. There is currently no effective, approved contrast agent for this imaging techniq ue. OBJECTIVE: We evaluated five agents (barium sulfate, iohexol, propyliodone oily, propyliodone aqueous, and perflubron) in terms of image quality, histologic changes, and effects on hemodynamics, blood gases, and standard laboratory tests in New Zealand White rabbits. MATERIALS AND METHODS: Animals were anesthetized and intubated. Each contrast agent (0.25 ml/kg) was administered intratracheally. Three animals in each group had intravenous lines placed for blood sampling and blood pressure monitoring and were sacrificed at 1 h. An additional three animals for each agent were sacrificed at 24 h and 1 week after imaging. Blood samples were taken immediately before contrast instillation and at 1 h postbronchography. Fluoroscopic images were recorded on standard VHS video tape and evaluated in blind fashion. Segments of lung tissue and bronchi were obtained for histologic examination. RESULTS: Necrosis and/or inflammatory infiltrates were noted in 78 % of the bronchograms performed with propyliodone aqueous, 67 % with propyliodone oily, 55 % with perflubron, and 33 % with iohexol 120, 240 and 350. No histologic damage was observed with barium. The propyliodones gave the best-quality imaging results and the most histologic changes. Iohexol, in any concentration, gave the least acceptable images and a moderate number of histologic changes. Barium sulfate demonstrated acceptable images with virtually no histologic changes. CONCLUSION: From the histologic and imaging results, barium is the best available contrast material for bronchography.

Animals↗
PubMed1997

Carotid artery and jugular vein ligation with and without hypoxia in the rat.

A continuing concern about the use of extracorporeal membrane oxygenation (ECMO) is the cannulation of the common carotid artery or the internal jugular vein. The authors investigated the changes that might occur in the brain with neck vessel ligation in the normal and the hypoxic rat. Two groups of 60 rats each were studied. The first group was divided into three subgroups of 20 animals each. Subgroup 1 (HH) was hypoxic both 24 hours before and 24 hours after operation. Subgroup 2 (HN) (the ECMO model) was hypoxic before operation and recovered for 24 hours in room air. Subgroup 3 (NN) underwent the entire procedure in room air. For each oxygen environment, four different operations were performed: carotid artery ligation, jugular vein ligation, carotid artery and jugular vein ligation, and dissection of the vessels without ligation (sham). Thus each subgroup was further divided into four sub-subgroups based on the operation performed. Rats were again anesthetized after a 24-hour recovery period and killed using low, blunt cervical dislocation. In the first group of 60 rats, the skull was opened and the brain was carefully removed from the cranial vault and placed in a fixative. The brains were placed in a small magnetic resonance imaging (MRI) head coil in groups of five and scans were obtained to provide T1 and T2 images that correlated with histological sections. MRI scans were reviewed in random, blinded fashion by an imager unaware of how these animals had been treated. The brains were then sectioned coronally at six corresponding levels: frontal, mid and posterior cerebrum, midbrain, pons, and medulla. Histological examination was performed in blinded fashion. The number of lesions (usually ischemic as noted by a decrease in the number of neurons) was totaled for each area of the brain. There were no differences that were consistent or statistically significant in the MR images of brains removed from the head, although it would appear that rats with jugular vein and carotid artery ligation were relatively protected. In the HN group jugular vein ligation was worst, and adding carotid artery ligation was best. In the histological studies the NN group had significantly more lesions than the HH group (P < .01). The second group of 60 rats was divided and treated as the first group in all respects except that MRI was conducted immediately after death on intact heads, and no histological studies were performed. This was done to control for lesions that might have been produced by removal of the brains from the skulls. In this group all findings were right sided. One animal in the HN group showed midcerebral white matter edema after jugular and carotid ligation. Focal anterior cerebral edema was seen in another animal (HH) after isolated carotid ligation. An occipital infarct was found in one animal (HH) after both carotid and jugular ligation. The authors conclude that neck vessel ligation in the hypoxic or normoxic rat causes only occasional and sporadic brain injury much as is seen clinically in newborn ECMO patients.

Animals↗
PubMed1996

Extracorporeal membrane oxygenation in pediatric respiratory failure secondary to smoke inhalation injury.

Extracorporeal membrane oxygenation (ECMO) was used successfully in two children who had respiratory failure secondary to smoke inhalation injury. The first involved a 20% body surface area burn with initial carboxyhemoglobin of 26%. The patient developed varicella pneumonia, which complicated his respiratory failure; he was placed on ECMO for 7 days. The second infant had a 35% body surface area burn and carboxyhemoglobin of 30%. He underwent debridement and allografting while on ECMO, and was decannulated after 13 days. Anticoagulation for ECMO did not significantly interfere with dressing changes. Both patients had definitive autografting and were discharged home breathing room air.

Carboxyhemoglobin↗
PubMed1995

Pediatric cardiac surgical ECMO: multivariate analysis of risk factors for hospital death.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has emerged as an effective technique for the mechanical support of many pediatric postcardiotomy patients with medically refractory cardiac failure. METHODS: We retrospectively reviewed the records of 73 pediatric patients with congenital heart disease who were placed on ECMO support between August 1984 and February 1994. The patients were divided into groups defined by the timing of ECMO cannulation relative to the time of operation. Group 1 patients (n = 7, 9.6%) were placed on ECMO preoperatively. Group 2 patients (n = 66, 90.4%) were a heterogeneous population placed on ECMO at any interval after cardiac repair. Subgroup 2A consisted of patients (n = 17, 25.8%) who could not be weaned from cardiopulmonary bypass and were converted directly to ECMO support immediately after repair. Subgroup 2B patients (n = 49, 74.2%) were cannulated postoperatively after an initial period of clinical stability. RESULTS: Hospital survival for all study patients (42/73) and for group 2 patients (38/66) was 58%. Only 4 group 2A patients (23.5%) survived their hospitalization compared with 34 group 2B patients (69.4%) (p = 0.001). Multivariate analysis identified elevated right atrial pressure after ECMO decannulation (p = 0.049) and, possibly, membership in group 2A (p = 0.061) as independent risk factors for hospital death. CONCLUSIONS: Extracorporeal membrane oxygenation is most effective in salvaging pediatric cardiac surgical patients who demonstrate medically refractory hemodynamic deterioration at some interval after being successfully weaned from cardiopulmonary bypass. The right atrial pressure after extracorporeal membrane oxygenation decannulation is an independent predictor of hospital death.

Cardiopulmonary Bypass↗
PubMed1995

Does research during general surgery residency correlate with academic pursuits after pediatric surgery residency?

A study was designed to evaluate whether successful candidates in pediatric surgery have performed laboratory research with publication, and if such preparation leads to continued investigations. We requested a curriculum vitae from the 248 pediatric surgeons who began their pediatric surgery residencies (PSR) between 1979 and 1992. For nonresponders, data were collected from physician directories. Indicators of academic status, personal information, and publication data were obtained. Responders had more publications before, during, and after PSR. Those who published during general surgery residency (GSR) had more research years during their residency. Among responders, 59% had spent time in the laboratory, and the percentage with laboratory time increased over the study period. Those with laboratory experience had more laboratory and clinical papers before PSR. Ninety-four percent were from university-based GSRs and 6% were from community GSRs. University general surgery residents did not have more publications during GSR or PSR but had a greater number of publications after PSR. University general surgery residents had more laboratory publications during GSR and after PSR, but did not have more clinical publications. Publications during GSR and after PSR increased during the study period, but not during PSR. Time in the laboratory during GSR did not independently predict continued laboratory research. Those with laboratory papers during GSR did not publish more basic science papers after PSR. Several surgeons had basic science publications that were initiated only after their PSR. In a recent study that compared successful and unsuccessful PSR candidates, the successful candidates were found to have more publications.(ABSTRACT TRUNCATED AT 250 WORDS)

Achievement↗
PubMed1995

Extracorporeal membrane oxygenation as salvage in pediatric surgical emergencies.

Extracorporeal membrane oxygenation (ECMO) has become an established therapy for acute neonatal and pediatric respiratory failure. On an institutional level, once an ECMO program is well established, ECMO can be viewed as a logical extension of critical care for multisystem organ failure. The question left unanswered is "Should anyone die without being offered ECMO?" The authors reviewed a 10-year clinical experience with ECMO and its application as salvage therapy in pediatric surgical emergencies. Eight patients with life-threatening multisystem organ failure, from diverse causes, were treated; the survival rate was 50%. All survivors were neurologically intact at the time of discharge. The success of ECMO, coupled with improvements in technique, apparatus, and expertise, has allowed application of ECMO as an invasive extension of intensive care to diverse patient groups. These results have encouraged the authors to expand their indications and to push the "envelope" in offering ECMO to critically ill infants and children with life-threatening organ failure.

Critical Care↗
PubMed1995

Primary osteoma cutis.

This case report was presented because there are few published cases of a solitary lesion of primary osteoma cutis occurring in the foot. It is an unusual cause of heel pain.

Adult↗
PubMed1995

Congenital diaphragmatic hernia with or without extracorporeal membrane oxygenation: are we making progress?

BACKGROUND: Congenital diaphragmatic hernia (CDH) continues to have a high mortality rate (24 to 57 percent) despite changing management schemes, which include extracorporeal membrane oxygenation (ECMO) for treatment of associated persistent pulmonary hypertension of the newborn. STUDY DESIGN: The medical records of 123 acutely symptomatic newborns with CDH treated from 1972 to 1994 were retrospectively reviewed. Patients were divided into three groups to compare historical treatment modalities: group 1, no ECMO available; group 2, postoperative ECMO if necessary; and group 3, delayed repair with preoperative ECMO if necessary. The blood gas values, alveolar-arterial oxygen gradient (A-aDO2), mean airway pressure (MAP), and oxygenation (OI) and ventilation indices (VI) prior to treatment were compared between survivors and nonsurvivors. Chi-square and Student's t tests were used to determine statistical significance. RESULTS: The overall survival rate was 41 percent: 27 percent in group 1, 45 percent in group 2, and 39 percent in groups 3. If those who were not candidates for ECMO were excluded from analysis, the survival rate improved to 35 percent in group 1, 51 percent in group 2, and 50 percent in group 3. No published prognostic scoring system, such as arterial blood gas values, A-aDO2 gradient, MAP, OI, or VI consistently distinguished survivors from nonsurvivors. Extracorporeal membrane oxygenation decreased the mortality rate of patients having large defects. CONCLUSIONS: Prognostic scoring systems do not predict which patients with CDH should be treated. Extracorporeal membrane oxygenation has improved survival in newborns with CDH who present in early respiratory distress. There is no advantage or disadvantage to using ECMO prior to repair of CDH.

Extracorporeal Membrane Oxygenation↗
PubMed1994

Extracorporeal CO2 removal in a lung lavage model of respiratory failure.

Extracorporeal life support (ECLS) is a recognized treatment for neonatal respiratory distress unresponsive to other forms of therapy. Variations of this technique are being developed in an effort to extend its applicability and safety. Extracorporeal CO2 removal (ECCO2R) is one such modification that requires blood flows of 20% to 50% of cardiac output and therefore lends itself to percutaneous venous cannulation. The authors evaluated ECCO2R in conjunction with low-frequency ventilation, using a lung lavage-induced model of respiratory failure in rabbits. Six rabbits were lavaged an average of 9 times with 15 mL/kg Plasma-Lyte A at 37 degrees C via an endotracheal tube. Incremental ventilatory changes were made during lavage, to an FIO2 of 1.0, rate of 80, peak inspiratory pressure (PIP) of 37 cm H2O, and positive end-expiratory pressure (PEEP) of 4 cm H2O. Arterial blood gas values of PaO2 < 40 mm Hg and PaCO2 > 60 mm Hg resulted, meeting our criteria for respiratory failure. The rabbits were placed on veno-venous ECCO2R using a 0.8-m2 hollow fiber oxygenator and a commercially available double-lumen dialysis catheter. Blood flows of 10 to 20 mL/kg/min were used to manage CO2 removal. A low-frequency ventilation technique was employed using an FIO2 of 1.0 and a rate of 5 breaths per minute. PEEP was increased incrementally to maintain the PaO2 above 80 mm Hg. After initiation of ECCO2R, the arterial PaO2 increased to 165 +/- 109 mm Hg, with PEEP above 15 cm H2O, and PaCO2 decreased to 37 +/- 5 mm Hg, with a bypass flow rate of 15 mL/kg/min.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation has now evolved into standard therapy for patients unresponsive to conventional ventilatory and pharmacological support. This article presents a clinical review of extracorporeal life support and its application to neonatal and pediatric patients as well as children requiring circulatory support after open heart surgery.

Cardiac Surgical Procedures↗
PubMed1993

Performance of plasma-perfused, microencapsulated hepatocytes: prospects for extracorporeal liver support.

The growing success of liver transplantation and the shortage of donor livers has turned attention to the possibility of utilizing hepatocytes within artificial liver support systems to allow time for donor livers to become available and to improve the condition of patients with hepatic failure. This study evaluated encapsulated hepatocytes, a technology which might allow the possibility of using xenogenic or human hepatoma cells. Rabbit hepatocytes were encapsulated using the ionic polysaccharides carboxymethylcellulose, chondroitin sulfate A, chitosan, and polygalacturonic acid. Encapsulated cells were maintained in perfusion culture for at least 6 days in heparinized, normal human plasma or in a defined culture medium. Parallel cultures of plated hepatocytes were also conducted. The metabolic capability of the cells was evaluated by following the rates of urea, albumin, and transferrin synthesis and the transformation rate of the drug antipyrine. Protein synthesis and ureogenesis in plasma were depressed from the levels expressed in defined culture medium. Drug detoxification as measured by antipyrine metabolism appeared to be enhanced in plasma. We conclude that encapsulated rabbit hepatocytes retain significant levels of function for at least 6 days of perfusion with human plasma, suggesting the feasibility of this technology as a potential method of short-term liver support.

Albumins↗