Preoperative gabapentin: the effect on ropivacaine subarachnoid block and hemodynamics.
BACKGROUND
Gabapentin is an adjuvant analgesic and may enhance the spread of subarachnoid block. We investigated the effects of pretreatment with gabapentin on subarachnoid block characteristics and hemodynamics.


METHODS
Seventy patients undergoing transurethral procedures under subarachnoid anesthesia with 2.2 mL of 0.75% ropivacaine were randomly assigned to receive preoperatively 400 mg of gabapentin 6 hourly, up to a total dose of 1200 mg, or placebo. Sensory and motor blocks were assessed every 30 min until regression of sensory block to L4. At the same time intervals, systolic and diastolic arterial blood pressures and heart rate were recorded.


RESULTS
There were no differences between groups in the sensory block levels or degree of motor block. Sensory block 150 min after the subarachnoid injection had regressed to L4 in 26 of 32 patients in the gabapentin group and in 25 of the 33 patients in the control group. Systolic arterial blood pressure was decreased in the gabapentin group (P = 0.002 for the main effect of group, and P = 0.03 at 60 min between the groups). The diastolic arterial blood pressure did not differ between the groups, but overall, the heart rate was more rapid in the gabapentin group (P = 0.002, but only for baseline values between the groups, P = 0.036).


CONCLUSIONS
Pretreatment with gabapentin had no effect on the spread of sensory block or the regression of motor block but was associated with lower systolic arterial blood pressure values in patients undergoing subarachnoid anesthesia with ropivacaine.
Fassoulaki
Argyro
A
Department of Anesthesiology, Aretaieio Hospital, Medical School, Athens, Greece. fassoula@aretaieio.uoa.gr
Chatziara
Vassiliki
V
Melemeni
Aikaterini
A
Zotou
Marianna
M
Sarantopoulos
Constantine
C
D000284:Administration, Oral; D000368:Aged; D000577:Amides; D000588:Amines / Q000008:administration & dosage / Q000627:therapeutic use*; D000700:Analgesics / Q000008:administration & dosage / Q000627:therapeutic use*; D000779:Anesthetics, Local; D001794:Blood Pressure / Q000187:drug effects; D003509:Cyclohexanecarboxylic Acids / Q000008:administration & dosage / Q000627:therapeutic use*; D000077206:Gabapentin; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D008875:Middle Aged; D009407:Nerve Block; D010212:Papilloma / Q000601:surgery; D011300:Preoperative Care; D000077212:Ropivacaine; D012684:Sensory Thresholds / Q000187:drug effects*; D013346:Subarachnoid Space; D013997:Time Factors; D001749:Urinary Bladder Neoplasms / Q000601:surgery; D005680:gamma-Aminobutyric Acid / Q000008:administration & dosage / Q000627:therapeutic use*
D000577:Amides; D000588:Amines; D000700:Analgesics; D000779:Anesthetics, Local; D003509:Cyclohexanecarboxylic Acids; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin; D000077212:Ropivacaine