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D Hatch

Publications and source records attributed to D Hatch.

30 records · Page 2Linked to original sources
PubMed1986

Constant flow ventilation in anesthetized patients: efficacy and safety.

Constant flow ventilation (CFV) maintains normal gas exchange in apneic dogs and has potential clinical application during thoracic surgery or pulmonary edema. We compared CFV and intermittent positive pressure ventilation (IPPV) in five healthy, anesthetized, (fentanyl, diazepam, and nitrous oxide) and paralyzed patients undergoing nonthoracic operations. Constant flow ventilation was delivered at a total flow of 0.9-1.6 L . kg-1 . min-1 (nitrous oxide-oxygen at 1:1) into two tubes of 2.5-3.5 mm inner diameter attached to each side of an 8-9 mm inner diameter orotracheal tube (OTT). Under bronchoscopic guidance, the CFV-OTT was advanced to position each ventilating tube at a mainstem bronchial orifice. Gas exhausted through the OTT lumen. If intrathoracic pressure exceeded a preset limit, a solenoid valve automatically interrupted gas flow to the patient to prevent barotrauma. Compared to IPPV, during CFV for up to 30 min average PaCO2 increased to 69.2 +/- 14.5 from 35.9 +/- 2.9 mm Hg, reflecting a calculated alveolar ventilation (VA) of 46 +/- 22% of the eucapnic level. We suggest that a technique combining CFV at lower flow rates with IPPV may prove clinically useful by allowing decreased tidal volume and inspiratory pressure while maintaining normal VA.

Adult↗
PubMedDate not supplied

Improved accuracy of the occlusion technique for assessing total respiratory compliance in infants.

The occlusion technique to measure total respiratory system compliance (Cocc) was used in 28 sedated infants with a variety of cardiopulmonary diseases and 14 anaesthetised infants during the first 2 years of life. In this report, we describe some of the potential problems in the technique and how to avoid them. Invalidation of the occlusion technique because of consistent failure to relax during brief airway occlusions occurred in only four of 42 infants despite the fact that only four infants were studied during the first month of life and 17 were between 12 and 26 months old. The technique was invalidated in two intubated infants because of persistent leaks around the endotracheal tube. In the remaining 36 infants, data sometimes had to be excluded as a result of instability and end-expiratory volume, intermittent leaks, or failure to relax during occlusions performed at low lung volumes or during inspiration. However, by performing 15-25 occlusions per infant, it was possible to obtain sufficient reliable data for accurate analysis of Cocc in all these infants. Providing that the potential errors and limitations of the occlusion technique are recognized, it appears to be applicable to a wide range of healthy and sick infants.

Forced Expiratory Flow Rates↗
PubMedDate not supplied

Treatment of bacterial meningitis with ceftazidime.

Ceftazidime was prospectively evaluated in the treatment of bacterial meningitis in 19 pediatric patients. Haemophilus influenzae type b (HIB) was the etiologic agent in 17 patients, and Streptococcus pneumonia and Neisseria meningitidis were the etiologic agents in one patient each. Ceftazidime was administered intravenously in a dosage of 150 mg/kg/day divided into eight hourly doses for a mean of 15 days (range, 14 to 22 days) for H. influenzae type b meningitis. The clinical and microbiologic response was appropriate in all cases. The mean ceftazidime CSF concentration was 6.7 micrograms/ml at approximately 2 hours following iv infusions. This concentration was 16- to greater than 100-fold the minimal bactericidal concentration determined for the isolated pathogens. These preliminary observations support ceftazidime as a candidate cephalosporin for the treatment of bacterial meningitis caused by H. influenzae. Additional study is required to further define its role in meningitis caused by S. pneumoniae and N. meningitidis.

Adolescent↗
PubMedDate not supplied

Evaluating postoperative cataract patients using the Kowa Flare Cell Meter.

The estimation of flare and cell in the anterior chamber is an important part of the postoperative care of patients who have had cataract surgery. The Kowa Flare Cell Meter uses a laser beam for a probe of light, lines it up precisely in a specially modified slit lamp, and controls and measures the results with a computer. The Kowa Flow Cell Meter incorporates a computer for input of demographics and a screen display and printer for output of the results. The anterior chamber findings are displayed both numerically and graphically.

Cataract↗