Autonomic function following acute organophosphorus poisoning: a cohort study.
Autonomic dysfunction after chronic low level exposure to organophosphorus (OP) pesticides has been consistently reported in the literature, but not following a single acute overdose. In order to study autonomic function after an acute OP overdose, sixty-six overdose patients were compared to 70 matched controls. Assessment of autonomic function was done by heart rate response to standing, deep breathing (HR-DB) and Valsalva manoeuvre; blood pressure (BP) response to standing and sustained hand grip; amplitude and latency of sympathetic skin response (SSR); pupil size and post-void urine volume. The patients were assessed one and six weeks after the exposure. The number of patients who showed abnormal autonomic function compared to standard cut-off values did not show statistically significantly difference from that of controls by Chi-Square test. When compared to the controls at one week the only significant differences consistent with autonomic dysfunction were change of diastolic BP 3 min after standing, HR-DB, SSR-Amplitude, SSR-Latency, post-void urine volume and size of the pupil. At 6 weeks significant recovery of autonomic function was observed and only HR-DB was decreased to a minor degree, -5 beats/min [95%CI 2-8]. This study provides good evidence for the lack of long term autonomic dysfunction following acute exposure to OP pesticides.
Department of Pharmacology, Faculty of Medicine, University of Ruhuna, Karapitiya, Galle, Sri Lanka. sudheerasj@yahoo.com
Sudheera S
SS
Jayasinghe
Kithsiri D
KD
Pathirana
D000328:Adult; D001341:Autonomic Nervous System / Q000187:drug effects / Q000503:physiopathology*; D001342:Autonomic Nervous System Diseases / Q000139:chemically induced* / Q000503:physiopathology*; D001794:Blood Pressure / Q000187:drug effects; D015331:Cohort Studies; D005260:Female; D018737:Hand Strength; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D062025:Organophosphate Poisoning; D010575:Pesticides / Q000506:poisoning*; D011187:Posture; D011680:Pupil / Q000187:drug effects; D012119:Respiration / Q000187:drug effects; D014636:Valsalva Maneuver / Q000187:drug effects; D055815:Young Adult
D010575:Pesticides