Abstract

Objectives: This prospective, randomised and double blinded study compared incidences of postoperative urinary retention (POUR) at three volumes of colloid co-loading during spinal anaesthesia (SA).

Materials and Methods: Ninety nine ASA I or II patients between 18-50 years old were randomised into either Group A (2.5 mL/kg), Group B (5.0 mL/kg) or Group C (7.5 mL/kg) volume co-loading with Gelofusine®. All patients voided spontaneously prior to SA. Ultrasonic bladder volumes were assessed at 2 and 4 hours post SA. Mean arterial pressure (MAP) and heart rate (HR) were recorded perioperatively.

Results: Incidence of POUR occurred only in Group C at 27.3%. Cumulative bladder volumes at 4 hours were significantly higher in Group C (460.8 ± 49.5 mL), followed by Group B (351.2 ± 65.0 mL) and Group A (235.2 ± 35.7 mL). The rate of bladder urine volume accumulation among groups was highest in Group C (110.5 ± 17.6 mL/hour) followed by Group B (84.3 ± 21.1 mL/hour) and Group A (61.3 ± 16.3 mL/hour). Mean colloid volume administered was 522.2 ± 69.1 mL (p<0.001) in patients with POUR. The time to spontaneous micturition was significantly earlier in Group C at 344.5 ± 58.1 minutes. The MAP was significantly lower in Group A during the initial 20 minutes post SA and 15.2% required a single rescue dose of ephedrine to maintain haemodynamic stability.

Conclusion: The incidence of POUR was significantly higher when co-loaded with 7.5 mL/kg of colloid. Mean arterial pressures were more stable when co-loaded with colloid volumes exceeding 5.0 mL/kg.