Peripheral Neuropathy in Children With Chronic Kidney Disease: Are We Looking Enough?

Background: Peripheral neuropathy in chronic kidney disease (CKD) is the most common neurological complication. We aimed to look at the prevalence and patterns of neuropathy in children with CKD. Methods: This cross-sectional study was conducted over 1 year in children with CKD, stage III and above. Nerve conduction studies (NCS) were performed as per standard protocols using surface electrodes on the muscles and by supramaximal stimulation of the corresponding nerves. Presence of electrophysiological abnormalities in the absence of clinical symptoms or signs was considered as subclinical neuropathy. Results: Nearly 45 children were evaluated. The majority were males (n = 39, 86.7%). The mean age was 7.9 ± 3 years (range 2-14). The mean estimated glomerular filtration rate (GFR) at enrolment was 23.3 ± 14.6 mL/min/1.73 m2 (range 5-67). The majority of children were in stage III (n = 19, 42%), followed by stages V (n = 15, 33%) and IV (n = 11, 25%). There was no evidence of clinical neuropathy; 13 children (29%) showed subclinical neuropathy. All the nerves had an axonal pattern of involvement. Motor polyneuropathy was most common type of peripheral neuropathy. The commonest nerves involved were tibial and common peroneal nerves. There were no biochemical or clinical predictors of neuropathy in our cohort. Conclusion: The prevalence of subclinical neuropathy is high in children with CKD, stage III and above. Axonal motor polyneuropathy is the predominant pattern. Electrophysiological assessment of nerve function should be routinely done in children with advanced stages of CKD to prevent chronic complications.

Bronchoscopic resection of a tracheobronchial leiomyoma in a pregnant patient.

Flexible bronchoscopy, therapeutic bronchoscopy and other procedures requiring anesthesia are generally avoided in pregnancy and postponed until after delivery if possible. We report a case of a parturient with an abnormal chest radiograph and mild obstructive symptoms of unknown etiology. At bronchoscopy, a tumor associated with post-obstructive suppuration was found and excised using electrocautery snare and cryotherapy, for restoration of airway patency. Coordination between pulmonary, obstetric, anesthesia, neonatology and thoracic surgery services was essential in ensuring success and the safety of the mother and fetus.

Correlation between complication rate and perioperative risk-factors in superior pedicle reduction mammaplasty: our experience in 127 patients.

Reduction mammaplasty, one of the most common plastic surgery procedures, has been shown to confer significant sustained health benefits for patients with symptomatic breast enlargement providing a remedy for back, neck, and shoulder pain. Unfortunately, operations of breast reduction may lead to patient dissatisfaction for poor aesthetic outcome due to complications. Complications, including infection, hematoma, seroma, dehiscence, fat necrosis, and skin loss, may occur in as many as 50% of patients. Unacceptable scarring has also been reported. Complication data revealed several significant features, although there isn't much objective evidence to support that. Over the period 2004-2008, 127 consecutive patients were admitted for breast reduction surgery, data have been analyzed retrospectively to determine whether any correlation could be found between complication rate and perioperative risk-factors using a multifactorial ANOVA F-test. Analysis of variables associated with complications showed that, after adjusting for age and smoking status, only BMI was associated with any complication (p < 0.05). By power analysis, based on a comparison of three proportions, a power of 92% with a significance level of 0.05 was found for the hypothesis that the outcomes of the procedures depends on BMI.

Deposition pattern of heliox-driven bronchodilator aerosol in the airways of stable asthmatics.

To compare the deposition patterns of heliox-driven and air-driven radiolabeled bronchodilator aerosol, a prospective randomized study was undertaken at the Ben Taub Hospital in Houston, Texas. The working hypothesis was that nebulization with heliox would improve the peripheral deposition of a bronchodilator aerosol. Twelve mild-moderate known asthmatics were recruited for the study. They were asked to withhold medications for 8-24 hours prior to reporting for the study. Each subject was randomized to receive either heliox or oxygen for delivery of albuterol labeled with Tc-99m DTPA. Prior to the nebulization, baseline spirometry was performed. Following nebulization, the subjects were scanned for 1,000,000 counts on the ADAC Genesis Scanner. A postbronchodilator spirometry was then performed. Subjects returned about a week later, this time to have the same process repeated with the other gas. The normalized pixel counts were obtained, and the frequency distribution histograms were constructed for each of the deposition images. Skew and kurtosis were calculated. A lower skew and kurtosis value suggests a more peripheral distribution of the bronchodilator, whereas a higher pixel count corresponds with an increased area and uniformity of deposition. There were no statistically significant differences in baseline PFTs on the 2 days of the study. The pixel count was statistically higher after the heliox-driven nebulization than the air-driven nebulization. The skew and kurtosis values were lower after the heliox-driven nebulization than after the air-driven nebulization of radiolabeled aerosol. All patients had a good bronchodilator response with either driving gas. However, the degree of improvement was more with heliox-driven nebulization than with air-driven nebulization. We conclude that aerosol delivery with heliox results in more uniform and peripheral deposition. Thus, this mode of delivery can be used when uniform, peripheral deposition is desired as with drug delivery during an exacerbation or with aerosolized gene therapy.

Nontypeable Haemophilus influenzae in the lower respiratory tract of patients with chronic bronchitis.

The frequency of colonization and intracellular localization of nontypeable Haemophilus influenzae (NTHi) in the lower respiratory tract was determined in healthy adults and in clinically stable and acutely ill chronic bronchitis (CB) patients. NTHi was recovered from bronchial wash or bronchial brush specimens in 6 of 23 (26%) stable CB patients and in 1 of 15 (7%) CB patients with a respiratory exacerbation. No NTHi (0 of 26) was recovered from lower tract specimens of healthy adults undergoing anesthesia for elective surgery. Molecular typing of NTHi strains revealed that five of nine patients with stable CB had different strains in upper respiratory tract and bronchial wash/brush specimens collected simultaneously. Four stable patients with CB had different strains recovered on repeat bronchoscopy. These results demonstrate the frequent colonization of the lower airways of stable CB patients with multiple strains of NTHi. Bronchial biopsies also were examined for intracellular NTHi by in situ hybridization and immunofluorescence microscopy. Intracellular NTHi were found in 0 of 7 healthy adults, 8 of 24 patients with clinically stable CB, and 13 of 15 acutely ill CB patients. This observation suggests a role for intracellular infection by NTHi in the pathogenesis of exacerbations of CB.

Cation metabolism during propofol sedation with and without EDTA in patients with impaired renal function.

OBJECTIVE: To compare the effects of propofol with and without disodium edetate (EDTA) on cation metabolism in intensive care unit (ICU) patients with renal insufficiency who received propofol or propofol plus EDTA (propofol EDTA) for sedation and mechanical ventilation. DESIGN: Double-blind, randomised, multicentre study. SETTING: Medical and surgical ICUs from 5 hospitals. PATIENTS: Thirty-nine ICU patients with acute and chronic renal impairment expected to require at least 24 hours of continuous sedation and respiratory failure necessitating mechanical ventilation. INTERVENTIONS: Propofol or propofol EDTA administered for sedation by continuous intravenous infusion. MEASUREMENTS AND RESULTS: The depth of sedation, as measured by the Modified Ramsay Sedation Scale, was similar in the 2 groups, when adjusted for dosing differences. The amount of propofol required to maintain adequate sedation was decreased in both groups compared to propofol requirements in ICU patients with normal renal function. EDTA levels were elevated at baseline in both groups. In the propofol EDTA group, the EDTA levels increased further by 20 % but decreased to below baseline EDTA levels at 48 hours after sedation. In the propofol group, EDTA levels decreased during sedation and remained below baseline levels at 48 hours after sedation. PATIENTS in both groups were hypocalcaemic and hyperphosphataemic at baseline with low levels of 1,25-dihydroxyvitamin D and elevated parathyroid hormone (PTH) levels. Other than a slight difference in ionised serum calcium levels at 4 h after the start of sedation, there were no significant differences observed in serum calcium levels between the two groups. There were no significant differences in 1,25-dihydroxyvitamin D or PTH levels over time between the two groups. There was no significant effect on renal function in either group. CONCLUSIONS: The results of this study suggest that adding EDTA to propofol does not adversely affect cation homeostasis or renal function when used for sedation of ICU patients with renal insufficiency. Although EDTA levels increased over time from baseline levels in patients with renal insufficiency who receive propofol EDTA, this increase does not appear to be clinically significant, and EDTA levels return to below baseline levels within 48 hours of discontinuing the propofol EDTA infusion. The efficacy of propofol with and without EDTA also appears comparable in these patients.

Infection of primary human bronchial epithelial cells by Haemophilus influenzae: macropinocytosis as a mechanism of airway epithelial cell entry.

Nontypeable Haemophilus influenzae is an exclusive human pathogen which infects the respiratory epithelium. We have initiated studies to explore the interaction of the nontypeable H. influenzae strain 2019 with primary human airway epithelial cells by electron and confocal microscopy. Primary human airway cell cultures were established as monolayers on glass collagen-coated coverslips or on semipermeable membranes at an air-fluid interface. Scanning electron microscopy indicated that bacteria adhered to nonciliated cells in the population. The surface of infected cells showed evidence of cytoskeletal rearrangements manifested by microvilli and lamellipodia extending toward and engaging bacteria. Confocal microscopic analysis demonstrated that infection induced actin polymerization with an increase in cortical actin as well as evidence of actin strands around the bacteria. Transmission electron microscopic analysis showed lamellipodia and microvilli surrounding organisms, as well as organisms adherent to the cell surface. These studies also demonstrated the presence of bacteria within vacuoles inside of airway cells. Confocal microscopic studies with Texas red-labeled dextran (molecular weight, 70,000) indicated that H. influenzae cells were entering cells by the process of macropinocytosis. These studies indicate that nontypeable H. influenzae can initiate cytoskeletal rearrangement within human airway epithelium, resulting in internalization of the bacteria within nonciliated human airway epithelial cells by the process of macropinocytosis.

Electrical and lightning injuries.

Electricity and lightning can cause injury in a variety of ways, some of which may remain hidden from the unsuspecting physician until it is too late. Prompt and, if necessary, prolonged resuscitation are of proven benefit. Particular attention must be paid to the patient who suffers high-voltage injury, and deep electrothermal burns on damage to vital organs should be excluded. Uncommonly late sequelae are seen, and such patients require appropriate care.

Case discussions on the pathophysiology and clinical features of near-fatal asthma episodes.

This article reviews the definition of near-fatal asthma. The slow-onset, late arrival group and the sudden-onset groups of near-fatal asthma patients are discussed. Risk factors for near-fatal asthma and the pathologic differences between the two groups are elucidated.

Respiratory tract viral infections in inner-city asthmatic adults.

BACKGROUND: Respiratory tract viral infections (RTVIs) have been identified frequently in association with asthma exacerbations in children, but few studies have shown similar rates of viral infections in adults with asthma. Further studies using newer diagnostic techniques to evaluate the frequency of RTVIs in adults with acute exacerbations of asthma need to be performed. METHODS: Twenty-nine asthmatic adults were recruited from the pulmonary clinic of an urban county hospital and were followed up in a longitudinal cohort study for signs and symptoms of asthma and RTVI. One hundred twenty-two asthmatic adults presenting to the emergency department (ED) of the same hospital with acute symptoms of asthma underwent evaluation for RTVI in a cross-sectional prevalence study. In both studies, respiratory secretions and paired serum samples were collected from subjects with acute wheezing episodes and evaluated using virus culture, serologic testing, and reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: In the longitudinal cohort study, 138 respiratory illnesses, of which 87 were asthma exacerbations, were evaluated; 41% of all illnesses and 44% of asthma exacerbations were associated with an RTVI. In the ED study, 148 asthma exacerbations were evaluated; 55% were associated with an RTVI. An RTVI was identified in 21 (50%) of 42 of the subjects hospitalized in the ED study. Picornaviruses (rhinoviruses), coronaviruses, and influenza viruses were the most commonly identified causes of RTVI. Forty-six (60%) of the 77 picornavirus infections and 22 (71%) of the 31 coronavirus infections were identified only using RT-PCR. CONCLUSIONS: Asthmatic exacerbations in adults are frequently associated with an RTVI. Identification of such infections often requires newer diagnostic methods, such as virus-specific RT-PCR. The high frequency of RTVIs identified in association with asthmatic exacerbations in adults from the inner city suggests that strategies for the prevention of RTVI should be targeted toward this population.

Angioedema: the role of ACE inhibitors and factors associated with poor clinical outcome.

OBJECTIVE: We sought to study the prevalence of angiotensin-converting enzyme (ACE) inhibitors, a cause of angioedema, and investigate any association between clinical findings at the time of presentation and clinical outcome. DESIGN AND SETTING: Retrospective review of the charts of all patients presenting with angioedema to the emergency department at our tertiary referral teaching hospital or clinics over a 4-year period. The charts were reviewed for documentation of chief complaint(s), physical findings, medical treatment, need for laryngoscopy and/or endotracheal intubation, triage, and probable etiology. RESULTS: Of the 40 patients presenting with angioedema in this study, 15 cases were caused by ACE inhibitors. They were the most common cause of angioedema, accounting for 38% of all cases. The incidence of ACE inhibitor-induced angioedema is estimated to be 0.14%. More patients with angioedema secondary to ACE inhibitors had complaints of odynophagia (p < 0.02), whereas only patients with non-ACE inhibitor causes of angioedema presented with pruritus (p < 0.02). Furthermore, patients presenting with an acute reaction within 24 h of exposure to the causative agent were more likely to require inpatient monitoring (p < 0.05). Both odynophagia and edema of the tongue were significant predictors for undergoing laryngoscopy (p < 0.001 and p < 0.02, respectively) and admission to the hospital (p < 0.05). CONCLUSION: ACE inhibitors are the number one cause of acute angioedema in this tertiary referral teaching hospital. Odynophagia and tongue swelling at the time of presentation had significant implications for diagnostic intervention and admission to the hospital.

Detection of Pneumocystis carinii in tracheal aspirates of intubated patients using calcofluor-white (Fungi-Fluor) and immunofluorescence antibody (Genetic Systems) stains.

OBJECTIVE: To compare the detection rate of Pneumocystis carinii in endotracheal aspirates with that rate in bronchoalveolar lavage fluid, using calcofluor-white (Fungi-Fluor) and immunofluorescence antibody (Genetic Systems) staining methods. DESIGN: Prospective, consecutive cases. SETTING: Medical intensive care unit at Ben Taub General Hospital. PATIENTS: Thirty-one intubated patients admitted with respiratory failure and suspected P. carinii pneumonia. INTERVENTIONS: An endotracheal aspirate specimen was obtained after maximally advancing a closed-system suction catheter, instilling aliquot portions of saline, and suctioning the lavage fluid. This procedure was followed within 30 mins by fiberoptic bronchoscopy and bronchoalveolar lavage. MEASUREMENTS AND MAIN RESULTS: Endotracheal aspirate and bronchoalveolar lavage specimens from each patient were mixed with Saccomano's fixative, blended, and centrifuged. Using a modified method for P. carinii cysts, the sediment was stained with the test calcofluor-white stain Solution A and the test antibody stain. The test antibody stain on the bronchoalveolar lavage specimens was positive for P. carinii for 13 patients and was used as the standard for comparison. In the endotracheal aspirate specimens, the test antibody stain detected 12 (92%) P. carinii-positive patients while the test calcofluor-white stain detected ten (77%) P. carinii-positive patients. CONCLUSIONS: We described a simple method for obtaining, processing, and staining endotracheal aspirate specimens for P. carinii. Obtaining an endotracheal aspirate specimen did not require specially trained personnel or a specialized and more expensive catheter, and was not associated with any complications.

Accurate placement of central venous catheters: a prospective, randomized, multicenter trial.

OBJECTIVES: a) To define the frequency of dangerous (intracardiac) central venous catheter placement in a multicenter study of large community hospital intensive care units (ICUs) and to evaluate physician responses to this finding. b) To validate right atrial electrocardiography as a technique to assure adherence with recent Food and Drug Administration (FDA) guidelines regarding the location of central venous catheter tips. c) To conduct a literature review of vascular cannulation and its associated potentially lethal complications. DESIGN: Prospective, randomized, blinded, multicenter study. SETTING: Multidisciplinary ICUs in five large community teaching hospitals. PATIENTS: Consecutive patients (n = 112) who required a central venous catheter by either internal jugular vein or subclavian vein at four separate hospitals were assessed using 30-cm catheters. Consecutive patients (n = 50) in a fifth hospital who subsequently required a central venous catheter via the internal jugular vein or subclavian vein route were prospectively randomized to receive a 20-cm central venous catheter with either conventional surface-landmark guidance, or with the right atrial electrocardiography-guided technique. MAIN OUTCOME MEASURES: a) Occurrence rate of malpositioned central venous catheters. b) Ability of right atrial electrocardiography to aid in the accurate placement of central venous catheters. RESULTS: a) Using conventional placement techniques with a 30-cm catheter, 53 (47%) of 112 initial central venous catheter placements resulted in location of the catheter tip within the heart. Catheter tips were not repositioned to locations outside the right atrium after this finding was identified on initial post-procedure films. b) Using the right atrial electrocardiography technique to place 20-cm central venous catheters resulted in no catheter tip locations within the heart (0/25) vs. 14 (56%) of 25 (p < .0001) intracardiac placements using conventional techniques. c) The literature suggests that serious mechanical complications of central venous catheterization, although uncommon, are associated with a high mortality rate. Deaths are associated with intracardiac placement. CONCLUSIONS: a) The FDA guidelines regarding catheter tip location (catheter tip should not be in the right atrium) have not been widely publicized. b) The average safe insertion depth for a central venous catheter from the left or right internal jugular vein or subclavian vein is 16.5 cm for the majority of adult patients; a central venous catheter should not be routinely inserted to a depth of > 20 cm. Catheters longer than this size are rarely needed, and potentially dangerous. Catheter tip location is important to document following central venous catheter insertion. Thirty-centimeter central venous catheters should not be used when accessing the central circulation via internal jugular or subclavian veins. c) Right atrial electrocardiography is a technique that assures initial tip position outside the heart in accordance with FDA guidelines. This technique would virtually eliminate the major risk of death (i.e., cardiac perforation) associated with this procedure. d) Recently available, 15- and 16-cm central venous catheters have significant potential to minimize intracardiac placement of central venous catheters by either the internal jugular or subclavian vein route and may become the standard of care.

Fiberoptic bronchoscopy in the intensive care unit.

The primary uses of FFB in the intensive care unit are in the diagnosis of opportunistic infection and for airway management. In addition, use of PTC brush or BAL with quantitative cultures may allow identification of the specific cause of bacterial pneumonia. Determination of the location and cause of pulmonary hemorrhage is possible in the intubated patient without massive hemoptysis. Use of FFB in atelectasis is more controversial and less commonly encountered. Other uses include foreign body retrieval, tamponade of bleeding segments and diagnosis/treatment of BPF. In addition to development of technical skills and knowledge of the indications for FBB, critical care physicians should be aware of contraindications and potential complications, as well as steps to minimize the latter.