title: Haemodynamic effects of subarachnoid block in elderly patients.
abstract: We have studied the haemodynamic effects of subarachnoid block in elderly patients. Thirty patients were undergoing elective transurethral surgery and 18 non-elective orthopaedic surgery, predominantly fractured neck of femur. Systolic arterial pressure (SAP) was measured by automated oscillotonometry, central venous pressure (CVP) by manometer and cardiac index (CI), stroke index (SI) and heart rate (HR) by transthoracic electrical bioimpedance. Systemic vascular resistance index (SVRI) was derived. SAP decreased by more than 25% in 33 patients and SVRI showed similar decreases (P = 0.0001). CVP decreased (2.5 (SD 1.5) cm H2O) in all patients. CI was unaffected because a decrease in SI in some patients (13 (19)%; P = 0.01) was compensated for by an increase in HR (13 (13)%; P = 0.01). Decreases in SAP of 25% were treated initially with colloid solution 8 ml kg-1, which restored SAP in 19 patients. CVP, SI and HR were all restored to baseline values, however, SVRI was decreased further (P < 0.05). Fourteen patients required additional treatment with metaraminol which restored SVRI to baseline values. Patients with systolic hypertension were more likely to require treatment with metaraminol (P = 0.04).
authors.affiliation: Department of Anaesthesia and Intensive Care, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin.
authors.forename: L A
authors.initials: LA
authors.lastname: Critchley
authors.forename: J C
authors.initials: JC
authors.lastname: Stuart
authors.forename: T G
authors.initials: TG
authors.lastname: Short
authors.forename: T
authors.initials: T
authors.lastname: Gin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001340:Autonomic Nerve Block / Q000009:adverse effects*; D001794:Blood Pressure; D017558:Elective Surgical Procedures; D005260:Female; D006339:Heart Rate; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D007022:Hypotension / Q000209:etiology* / Q000628:therapy; D007430:Intraoperative Care / Q000379:methods; D008297:Male; D008680:Metaraminol / Q000627:therapeutic use; D008875:Middle Aged; D009985:Orthopedics; D011097:Polygeline / Q000627:therapeutic use; D014655:Vascular Resistance
chemical_list: D008680:Metaraminol; D011097:Polygeline