Biomedical subjects

Jonathan Critchlow

Publications and source records attributed to Jonathan Critchlow.

4 recordsLinked to original sources

PubMed2006

High-frequency probe ultrasonography has limited accuracy for detecting invasive adenocarcinoma in patients with Barrett's esophagus and high-grade dysplasia or intramucosal carcinoma: a case series.

AIM: To evaluate prospectively the accuracy of preoperative high-frequency (20 MHz) probe ultrasonography (HFPUS) for detecting invasive cancer in patients referred for esophagectomy because of an endoscopic biopsy diagnosis of high-grade dysplasia (HGD) or intramucosal carcinoma (ICA) in Barrett's esophagus (BE). PATIENTS AND METHODS: Nine consecutive male patients (median age of 69 yr) who were referred for esophagectomy for HGD or ICA in BE agreed to participate. We performed conventional upper gastrointestinal endoscopy followed by HFPUS using a through-the-scope ultrasound probe (20 MHz), and we compared our preoperative findings with the pathologist's findings in the resected esophageal specimens. RESULTS: There was complete agreement between the postoperative pathological findings and the preoperative HFPUS findings in only 4 of the 9 patients. HFPUS resulted in two false-negative diagnoses of esophageal cancer (both had T1 lesions in the resected specimens), one false-positive diagnosis of esophageal cancer, and two errors in tumor staging (1 understaged, 1 overstaged). CONCLUSIONS: HFPUS has limited accuracy for identifying invasive cancer in patients found to have HGD or IMC in BE. Pending further refinements in technology, clinical management decisions in such patients should not be based solely on the results of HFPUS.

Adenocarcinoma↗

PubMed2003

Percutaneous tracheostomy--special considerations.

Percutaneous tracheostomy is safe and highly effective in well-trained hands in establishing a long-term artificial airway. Most alleged contraindications and some suggestions on how the procedures should be performed likely stem from early trials when only "perfect candidates" were chosen. Most of those contraindications should not be viewed as prohibitions, but as suggestions related to the skill level and training of the operator. We have used this technique in many situations where the small incision and tamponading effect of the tracheostomy tube has been quite beneficial, in selected patients with coagulapathies and severe venous congestion from superior cava syndromes as well as thyroid cancers, and in whom operative approaches would have been difficult. Knowing one's level of expertise and comfort in choosing and rejecting patients and procedures accordingly is the key to keeping PT a procedure with an excellent safety record. As the experience with PT grows, more and more perceived contraindications will disappear. Studies will address the role of PT in children and as a means of establishing emergent airway access. Also, the exact coagulation limits will need to be established. Few contraindications will most likely remain absolute, such as active infections over the proposed entry site, uncontrollable bleeding disorders and excessive ventilatory and oxygenation requirements. In our institution, taking into account these absolute contraindications, fewer than 5% of patients in need of a tracheostomy in the intensive care unit will undergo a primary open procedure.

Bronchoscopy↗

PubMed2002

A novel endoscopic full-thickness plicator for treatment of GERD: an animal model study.

BACKGROUND: This study was designed to demonstrate the efficacy and safety of a novel endoscopic full-thickness plication device for the treatment of GERD. METHODS: Gastric pressures and reflux from the gastroesophageal junction were measured in 20 excised pig stomachs before and after full-thickness plication within 1 cm of the gastroesophageal junction. Endoscopic full-thickness plication was performed on 11 live mini-swine that were subsequently observed for up to 12 weeks. OBSERVATIONS: Full-thickness plication significantly increased the mean intragastric pressure at which gastroesophageal reflux occurred. No complication, death, or sign of infection or tissue damage was noted by endoscopic observation or inspection of excised tissue at up to 12 weeks' follow-up. CONCLUSIONS: These studies in the ex vivo porcine model and live pigs suggest that full-thickness plication is effective and safe.

Animals↗

PubMed2002

Repeat bedside percutaneous dilational tracheostomy is a safe procedure.

OBJECTIVE: Previous tracheostomy has been considered a relative contraindication for percutaneous dilational tracheostomy. The objective of this study was to assess the safety of percutaneous dilational tracheostomy in critically ill patients with a history of previous tracheostomy. DESIGN: Retrospective, single-center case series of all consecutive patients requiring repeat tracheostomy for continued mechanical ventilatory support. SETTING: Intensive care unit of a tertiary-care referral center. SUBJECTS: Fourteen patients (eight female, six male) with a median age of 70 yrs (range, 33-94). All patients had previously undergone tracheostomy. INTERVENTION: Bedside percutaneous dilational tracheostomy. MEASUREMENT AND MAIN RESULTS: Subjects' previous tracheostomies dated back between 10 days and 8 yrs. Present intubation time before percutaneous dilational tracheostomy varied between 4 and 30 days. Bedside percutaneous dilational tracheostomy was performed successfully in all 14 patients by trained pulmonologists and surgeons. Eleven patients received an 8-mm and three received a 7-mm tracheostomy tube. There were no significant periprocedural complications, and no patient required surgical revision. The only postprocedural complication was accidental decannulation in one patient, which was managed with repeat percutaneous dilational tracheostomy. CONCLUSIONS: Trained physicians can safely perform bedside percutaneous dilational tracheostomy after previous tracheostomy. Percutaneous dilational tracheostomy offers an alternative to surgical tracheostomy in this particular patient population and should not be considered contraindicated.

Adult↗