Document Detail

Influence of autonomic neuropathy of different severities on the hypercapnic drive to breathing in diabetic patients.
MedLine Citation:
PMID:  9228370     Owner:  NLM     Status:  MEDLINE    
To investigate the effects of the autonomic nervous system on control of breathing, the neuromuscular (mouth occlusion pressure at 0.1 s after onset of inspiration [P0.1]) and ventilatory (minute ventilation [VE]) response to progressive hyperoxic hypercapnia was assessed in diabetic patients with autonomic dysfunction of different severity. Eighteen diabetics with autonomic neuropathy, nine with parasympathetic damage (DANp), and nine with parasympathetic and sympathetic damage (DANp+s), as indicated by marked postural hypotension, low increment of diastolic BP during sustained handgrip, and lowest resting catecholamine plasma levels, were studied together with a group of 10 diabetic patients without autonomic neuropathy (D) and a group of 10 normal subjects (C). All subjects had pulmonary function tests, including maximal voluntary ventilation and diffusion of carbon monoxide, measurements of respiratory muscle strength as maximal inspiratory mouth pressure (MIP) and maximal expiratory mouth pressure (MEP), and a CO2 rebreathing test (Read's method). Although in the normal range, lung volumes and FEV1 and forced expiratory flows were lower in the DANp and DANp+s groups than in the D and C groups, MIP and MEP were similar among C and diabetic groups, as well as resting P0.1, VE, tidal volume (VT), and respiratory rate (RR). The slope of the linear relationship between P0.1 and end-tidal PCO2 (PETCO2) was higher in DANp+s (0.63+/-0.07 cm H2O/mm Hg) than in C (0.45+/-0.06 cm H2O/mm Hg; p<0.05) and three times greater in DANp+s than in D (0.26+/-0.03 cm H2O/mm Hg; p<0.001) and DANp (0.24+/-0.03 cm H2O/mm Hg; p<0.001), who in turn showed a lower deltaP0.1/deltaPETCO2 than C. The VE increase with increasing PETCO2 was greater in DANp+s (3.70+/-0.85 L/min/mm Hg) than in DANp (2.13+/-0.20 L/min/mm Hg; p<0.05) and D (2.37+/-0.40 L/min/mm Hg; p=0.07), but not significantly higher from that of C (3.17+/-0.36 L/min/mm Hg). No differences were found for deltaVT/deltaPETCO2 among the groups, whereas the deltaRR/deltaPETCO2 relationship was steeper in DANp+s than in DANp (p<0.05) and D (p=0.055). These data reflect a depressed CO2 response both in D and DANp. The presumable decrease of the sympathetic nerve traffic in DANp+s appears to reverse this abnormality. DANp+s, however, exhibit an enhanced CO2 neuromuscular response even in respect to C, suggesting that the sympathetic nervous system might modulate the output of the respiratory centers to hypercapnic stimulus.
C Tantucci; L Scionti; P Bottini; M L Dottorini; E Puxeddu; G Casucci; C A Sorbini
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Chest     Volume:  112     ISSN:  0012-3692     ISO Abbreviation:  Chest     Publication Date:  1997 Jul 
Date Detail:
Created Date:  1997-08-12     Completed Date:  1997-08-12     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  0231335     Medline TA:  Chest     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  145-53     Citation Subset:  AIM; IM; S    
Clinica di Semeiotica e Metodologia Medica, University of Ancona, Italy.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Autonomic Nervous System Diseases / physiopathology*
Case-Control Studies
Death, Sudden / etiology
Diabetes Mellitus, Type 1 / physiopathology
Diabetes Mellitus, Type 2 / physiopathology
Diabetic Neuropathies / physiopathology*
Hemodynamics / physiology
Hypercapnia / physiopathology*
Middle Aged
Pulmonary Ventilation / physiology
Respiration / physiology*
Respiratory Center / physiopathology
Respiratory Function Tests
Respiratory Mechanics / physiology
Sleep Apnea Syndromes / etiology

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Implantation of Accuflex and Strecker stents in malignant bronchial stenoses by flexible bronchoscop...
Next Document:  Hypoxic ventilatory response and breathlessness following hypocapnic and isocapnic hyperventilation.