RESUMEN
OBJECTIVE: These studies evaluated the feasibility of using oral prolonged-release oxycodone/naloxone (OXN PR) for the management of acute postoperative pain. METHODS: Three studies were undertaken: (i) the analgesic efficacy of OXN PR was compared with prolonged-release oxycodone (OXY PR) in patients with knee arthroplasty in an immediate postoperative period (IPOP) study; (ii) OXN PR treatment was compared with other opioids during rehabilitation after knee arthroplasty in a noninterventional study (NIS); and (iii) surgical patients on other opioids were switched to OXN PR postoperatively during a quality improvement programme (QIP). RESULTS: In the IPOP study, the pain intensity at rest score decreased by a similar amount in the OXN PR and OXY PR groups, indicating similar analgesic efficacies. In the NIS, patient assessments indicated enhanced efficacy and tolerability for OXN PR compared with other opioids. The QIP indicated significant improvements in bowel function and less difficulty passing urine at the end of OXN PR treatment compared with baseline. No safety concerns were raised. CONCLUSIONS: The analgesic efficacies of OXN PR and OXY PR were similar in postoperative pain settings. OXN PR reduced the degree of restriction in relation to patients carrying out physiotherapy compared with other opioids, and improved bowel and bladder function.
Asunto(s)
Analgésicos Opioides/administración & dosificación , Naloxona/administración & dosificación , Oxicodona/administración & dosificación , Manejo del Dolor , Dolor Postoperatorio/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/efectos adversos , Artroplastia de Reemplazo de Rodilla , Estreñimiento/inducido químicamente , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/efectos adversos , Método Doble Ciego , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Naloxona/efectos adversos , Oxicodona/efectos adversos , Columna Vertebral/cirugía , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Recently, local infiltration analgesia (LIA) has been promoted for pain control after total hip arthroplasty (THA). We hypothesized that LIA would offer equal analgesic efficacy but less adverse effects, e.g., nausea and vomiting, when compared with an established regimen [intrathecal morphine (it-M)] after THA. METHODS: This randomized controlled trial comprised 60 patients undergoing THA under spinal anaesthesia. For LIA, the surgeon administered levobupivacaine, ketorolac and epinephrine at the surgical site intraoperatively. LIA patients received a LIA top-up through a wound catheter on the morning of the 1st post-operative day (POD). In group it-M, 0.1 mg morphine was given together with the spinal anaesthetic. Study parameters included pain scores, vital parameters and side effects, e.g., post-operative nausea and vomiting (PONV). Besides, levobupivacaine plasma concentrations were determined in 10 LIA patients. RESULTS: The median (25th/75th percentiles) rescue oxycodone demand differed significantly with LIA 15 (10/25) mg vs. 8.5 (1.5/15) mg with it-M (P < 0.006) during the day of surgery, but not anymore on 1st or 2nd POD. The LIA top-up had no effect. However, both analgesic regimens resulted in comparable pain scores and patient satisfaction. PONV incidence and medication did not vary significantly. LIA offered certain advantages regarding early post-operative mobilization. Maximum levobupivacaine plasma concentrations (229-580 ng/ml) remained under the toxic level. CONCLUSIONS: While LIA might enable earlier mobilization after THA, it was not associated with less nausea as compared with it-M. Less rescue oxycodone was given early after it-M, but urinary retention was more common in that group.
Asunto(s)
Analgésicos Opioides/uso terapéutico , Anestesia Local/métodos , Anestésicos Locales/uso terapéutico , Artroplastia de Reemplazo de Cadera/efectos adversos , Morfina/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/administración & dosificación , Periodo de Recuperación de la Anestesia , Anestésicos Locales/administración & dosificación , Anestésicos Locales/sangre , Bupivacaína/administración & dosificación , Bupivacaína/análogos & derivados , Bupivacaína/sangre , Bupivacaína/uso terapéutico , Ambulación Precoz , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Espinales , Levobupivacaína , Masculino , Persona de Mediana Edad , Morfina/administración & dosificación , Bloqueo Nervioso , Oxicodona/administración & dosificación , Oxicodona/uso terapéutico , Oxígeno/sangre , Manejo del Dolor/métodos , Dimensión del Dolor , Alta del Paciente , Satisfacción del Paciente , Náusea y Vómito Posoperatorios/epidemiología , Método Simple CiegoRESUMEN
BACKGROUND: The benefits of subacromial local anesthetic infusion are controversial. The aim of this study was to evaluate the efficacy of subacromial bupivacaine infusion after arthroscopic acromionplasty and rotator cuff procedures. METHODS: Ninety patients with subacromial impingement disease scheduled for elective shoulder arthroscopy were enrolled in this randomized, prospective and placebo-controlled study. The patients received subacromially either 5.0 mg/ml bupivacaine or 9.0 mg/ml saline at the rate of 2 ml/h post-operatively for 48 h. The primary outcome measure was the use of rescue oxycodone. The consumption of opioids, ibuprofen, paracetamol and codeine, and the intensity of pain were recorded. RESULTS: Patients receiving bupivacaine infusion used significantly less oxycodone compared with patients receiving saline [15 vs. 20 mg (median) oxycodone intravenously on the day of surgery, 0 vs. 10 mg (median) perorally on the first post-operative day]. There was no significant difference in the use of ibuprofen, paracetamol and codeine, except that paracetamol was used more in patients receiving saline during the day of surgery (P = 0.009). The pain scores of patients receiving bupivacaine were lower at 18 h (P = 0.008). Average pain scores for the worst pain experienced did not differ between the groups. There were three (4%) premature discontinuations because of technical problems. CONCLUSIONS: Considering the low need of opioids, expenses and technical problems in these patients, subacromial 5.0 mg/ml bupivacaine infusion 2 ml/h confers only moderate and probably clinically insignificant efficacy compared with placebo. This efficacy might be overweighed by the disadvantages.
Asunto(s)
Anestésicos Locales/uso terapéutico , Artroscopía , Bupivacaína/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Hombro/cirugía , Acetaminofén/administración & dosificación , Acetaminofén/uso terapéutico , Adulto , Anciano , Analgésicos no Narcóticos/administración & dosificación , Analgésicos no Narcóticos/uso terapéutico , Analgésicos Opioides/uso terapéutico , Anestésicos Locales/administración & dosificación , Anestésicos Locales/efectos adversos , Presión Sanguínea/efectos de los fármacos , Bupivacaína/administración & dosificación , Bupivacaína/efectos adversos , Mareo/inducido químicamente , Determinación de Punto Final , Femenino , Humanos , Inyecciones , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Oxicodona/uso terapéutico , Dimensión del Dolor/efectos de los fármacos , Estudios Prospectivos , Manguito de los Rotadores/cirugía , Tamaño de la Muestra , Resultado del TratamientoRESUMEN
BACKGROUND: The applicability of the Visual Analogue Scale (VAS) has been questioned in the assessment of pain in the elderly. We compared VAS with three other pain scales, Verbal Rating Scale (VRS), Red Wedge Scale (RWS) and Box Scale (BS), in hip fracture patients. METHODS: VAS, VRS, RWS and BS were compared in 140 analysable patients undergoing surgery, 70 with hip fracture and 70 with other lower limb trauma. Pain scores were recorded once a day, repeated after 10 min, for 4 subsequent days starting pre-operatively. The primary endpoint was the rate of successful pain measurements in hip fracture patients and 90% was chosen as a sufficient level for an applicable pain scale. RESULTS: Age was different between the groups (hip fracture 78 ± 11, other trauma 49 ± 11 years, P<0.0001). In hip fracture patients, 67-83% of pain measurements were successful with VAS, 82-100% with VRS, 83-96% with RWS and 79-91% with BS. The success rate with VAS was significantly <90% on 2 days (P<0.0001) and with BS on 1 day (P=0.04). All the other success rates with the four scales in both groups were above or not different from 90%. CONCLUSION: VRS and RWS were the most applicable scales, unlike VAS, which appeared to be an unreliable pain scale in perioperative hip fracture patients. In patients with other lower limb trauma, all four scales provided excellent applicability. Our results are in accordance with the accumulating evidence suggesting that VAS is not an ideal tool for pain measurement in the elderly.
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Fracturas de Cadera/complicaciones , Extremidad Inferior/lesiones , Dimensión del Dolor/métodos , Dolor/diagnóstico , Dolor/etiología , Adulto , Anciano , Interpretación Estadística de Datos , Determinación de Punto Final , Femenino , Finlandia , Fracturas de Cadera/cirugía , Humanos , Extremidad Inferior/cirugía , Masculino , Persona de Mediana Edad , Periodo PerioperatorioRESUMEN
BACKGROUND: We studied plasma bupivacaine concentrations in patients with a continuous subacromial bupivacaine infusion after an ambulatory arthroscopic shoulder surgery to evaluate whether it is feasible to discharge patients with an on-going infusion early on the operation day. METHODS: Sixteen ASA I-III patients undergoing elective arthroscopic shoulder surgery were randomized in 1:1 ratio to receive a continuous infusion of either 2.5 or 5.0 mg/ml bupivacaine subacromially for 48 h post-operatively. Before the commencement of the infusion, 20 ml of 5.0 mg/ml bupivacaine was injected subacromially in both groups. Plasma bupivacaine concentrations were defined as the primary endpoint and concentrations of its metabolites, side effects and pain scores as the secondary endpoints. RESULTS: The mean total plasma bupivacaine concentration increased up to 48 h, the highest mean being 0.87 (SD 0.30) µg/ml during the 5.0 mg/ml treatment and 0.24 (0.10) µg/ml during the 2.5 mg/ml bupivacaine treatment. After 48 h, there was a significant difference between the groups in the plasma levels. The highest mean 4-hydroxy-bupivacaine and desbutylbupivacaine concentrations were 0.11 and 0.22 µg/ml, respectively. In the pain scores, no significant difference was found. No clear signs of toxicity were observed. CONCLUSIONS: The concentrations of total bupivacaine and its metabolites remained below toxic levels. Excluding patients with renal or liver diseases, both 2.5 and 5.0 mg/ml bupivacaine as subacromial infusion 2 ml/h for 48 h following shoulder arthroscopy seem to be well tolerated, enabling patient discharge with an on-going infusion on the operation day. Because of similar side effects and pain scores in both groups, 2.5 mg/ml may be preferable.
Asunto(s)
Anestésicos Locales/sangre , Bupivacaína/sangre , Hombro , Analgesia Controlada por el Paciente , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/uso terapéutico , Anestésicos Locales/administración & dosificación , Anestésicos Locales/efectos adversos , Bupivacaína/administración & dosificación , Bupivacaína/efectos adversos , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Infusiones Intralesiones , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Morfina/administración & dosificación , Morfina/uso terapéutico , Dimensión del Dolor , Dolor Postoperatorio/tratamiento farmacológico , Náusea y Vómito Posoperatorios/epidemiología , Dolor de Hombro/cirugíaRESUMEN
BACKGROUND: In clinical practice, we noticed a greater than expected spread of sensory spinal block in patients with rheumatoid arthritis. We decided to test this impression and compared the spread of standard spinal anaesthesia in rheumatoid and non-rheumatoid control patients. METHODS: Spinal anaesthesia with 3.4 ml (17 mg) of plain bupivacaine was administered to 50 patients with seropositive rheumatioid arthritis and to 50 non-rheumatoid control patients. The protocol was standardised for all patients. All the patients were undergoing lower limb surgery and the rheumatoid patients were operated on due to their rheumatoid disease. The spread of sensory block was recorded 30 min from the dural puncture using a pin prick test and a cold ice-filled container. The impact of body mass index (BMI), height and age on the spread were analysed. RESULTS: The spread of sensory block was greater in patients with rheumatoid arthritis (15.6+/-3.1 dermatomes) than in non-rheumatoid patients (14.1+/-3.3 dermatomes) (P<0.05). Increasing BMI was related to cephalad spread of block in the rheumatoid group (P<0.05), but not in the control group. CONCLUSION: The mean spread of sensory block 30 min after the injection of plain bupivacaine was 1.5 segments cephalad in patients with rheumatoid arthritis than in those without this disease. BMI might be a patient-related factor contributing to the extent of the block in rheumatoid patients. These findings should be considered when performing a spinal block in rheumatoid patients.
Asunto(s)
Anestesia Raquidea/métodos , Artritis Reumatoide/fisiopatología , Índice de Masa Corporal , Sensación/efectos de los fármacos , Anestésicos Locales , Bupivacaína , Líquido Cefalorraquídeo/fisiología , Frío , Femenino , Humanos , Vértebras Lumbares , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Sensación/fisiología , Vértebras Torácicas , Resultado del TratamientoRESUMEN
BACKGROUND: Low-dose hyperbaric bupivacaine has been used to produce unilateral spinal anaesthesia for outpatient surgery. Unilateral spinal anaesthesia is associated with reduction of hypotension, faster recovery and increased patient satisfaction. Small doses of clonidine have shown effectiveness in intensifying spinal anaesthesia. We investigated the effect of adding 15 microg of clonidine to 5 mg hyperbaric bupivacaine on unilaterality. METHODS: Sixty patients undergoing outpatient knee arthroscopy were randomly allocated to receive either 1.2 ml (6 mg) of hyperbaric bupivacaine or a 1.2 ml solution containing 1.0 ml (5 mg) hyperbaric bupivacaine, 0.1 ml (75 microg) clonidine and 0.1 ml sterile water. The motor block was assessed by a modified Bromage scale and the sensory block by a pinprick. RESULTS: There was a significant difference in the spread of anaesthesia between the operated and contralateral sides in both groups. Seventy-seven per cent of the blocks were unilateral in group B and 73% in group B-C. There was no significant difference between the groups, in unilaterality. The motor block was prolonged in group B-C but it did not affect home-readiness. Patients receiving clonidine needed more vasopressors. There was a significant difference in blood pressures between the groups, being lower in group B-C after 1 h 45 min. CONCLUSION: Using 5 mg hyperbaric bupivacaine with 15 microg of clonidine, the unilaterality can be achieved and spinal anaesthesia intensified without affecting home-readiness. More vasopressors are needed in the beginning, but after the surgery patients experienced less pain.
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Agonistas alfa-Adrenérgicos , Procedimientos Quirúrgicos Ambulatorios , Anestesia Raquidea , Anestésicos Locales , Bupivacaína , Clonidina , Agonistas alfa-Adrenérgicos/administración & dosificación , Agonistas alfa-Adrenérgicos/efectos adversos , Adulto , Anestesia Raquidea/efectos adversos , Anestésicos Locales/administración & dosificación , Anestésicos Locales/efectos adversos , Artroscopía , Bupivacaína/administración & dosificación , Bupivacaína/efectos adversos , Clonidina/administración & dosificación , Clonidina/efectos adversos , Combinación de Medicamentos , Femenino , Lateralidad Funcional/efectos de los fármacos , Humanos , Rodilla/cirugía , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Vasoconstrictores/farmacologíaRESUMEN
We compared the pharmacokinetics of 10 mg oral oxycodone in four groups of 10 patients each, aged 20-40, 60-70, 70-80, and 80-90 years. Patients aged 70-80 and 80-90 years had 50-80% higher mean exposure to oxycodone (P < 0.05) and a twofold higher plasma oxycodone concentration (P < 0.05) than the young adults 12 h after ingestion of the drug. Because oxycodone pharmacokinetics depend to a great extent on the age of the subject, it is important to titrate the analgesic dose individually, particularly in the elderly.
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Analgésicos Opioides/sangre , Oxicodona/sangre , Administración Oral , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/administración & dosificación , Área Bajo la Curva , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxicodona/administración & dosificaciónRESUMEN
BACKGROUND AND OBJECTIVES: The clinical impact of patient positioning on motor block during unilateral spinal anesthesia was the focus of our study. It was assumed that a 45 degrees rotation toward the prone position would minimize blocking the ventral motor roots compared with using the conventional lateral decubitus position. METHODS: Spinal anesthesia with 3.4 mL of hypobaric 0.18% bupivacaine via a 27-gauge Whitacre needle was administered to 70 patients undergoing knee arthroscopy. The patients were kept either in a lateral decubitus position (group I) or rotated approximately 45 degrees toward the prone position (group II). No prophylactic vasopressors or infusions were used. The intensity of motor block (modified Bromage scale) was assessed for both the operative and the contralateral side. RESULTS: The patients in group I had a slightly more pronounced motor block, but statistical significance could be shown only 20 minutes following the block. There was no statistical difference between the groups in the need of additional analgesics during the operation. None of the patients needed general anesthesia. The hemodynamics were stable and none of the patients developed postspinal headache or backache. CONCLUSIONS: The position of the patient affects the spread of the spinal anesthesia when clearly hypobaric agents are used. However, this small modification in positioning of the patient did not lead to a clinically meaningful difference in the spread of the motor block.
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Anestesia Raquidea/métodos , Anestésicos Locales/administración & dosificación , Bupivacaína/administración & dosificación , Articulación de la Rodilla/cirugía , Bloqueo Nervioso/métodos , Postura/fisiología , Artroscopía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuronas Motoras/efectos de los fármacos , Raíces Nerviosas Espinales/efectos de los fármacosRESUMEN
BACKGROUND AND OBJECTIVES: Unilateral spinal anesthesia may be advantageous, especially in the outpatient setting. A low dose of anesthetic solution, pencil-point needle, low speed of intrathecal injection, and a lateral position have been reported to facilitate the production of unilateral distribution of spinal anesthesia. We compared the effects of plain and hyperbaric bupivacaine in attempting to obtain a unilateral spinal anesthesia for patients undergoing outpatient knee arthroscopy. METHODS: Sixty patients were randomly allocated to 2 groups to receive either 1.2 mL (6 mg) of plain 0.5% bupivacaine (group 1; n = 30) or 1.2 mL (6 mg) of hyperbaric 0.5% bupivacaine in 8% glucose (group 2; n = 30). Drugs were administered at the L2-3 interspace with the patient in the lateral position. Patients remained in this position for 20 minutes before being turned supine for the operation. Spinal block was assessed by pinprick and modified Bromage scale and compared between the operated and nonoperated sides. RESULTS: There was a significant difference between the operated and nonoperated side in both groups at all testing times, but a more unilateral spinal block was achieved with hyperbaric bupivacaine. Unilateral motor and sensory block was observed in 25 patients in group 2 (83%) and in 11 patients in group 1 (37%) (P <.01). The hemodynamic changes were minimal, since hypotension occurred only in 5.0% and bradycardia in 1.7% of all patients. CONCLUSION: In conclusion, the spinal anesthesia in both groups are suitable alternatives for adult outpatient knee arthroscopies, but hyperbaric bupivacaine provides us with a more unilateral spinal block.
Asunto(s)
Anestesia Raquidea , Anestésicos Locales/administración & dosificación , Bupivacaína/administración & dosificación , Adolescente , Adulto , Artroscopía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
We evaluated the effect of 25 microg of fentanyl added to bupivacaine on sensory and motor block. By using a double-blinded study design, 80 men undergoing urologic surgery were randomized into the following four groups: Group I, bupivacaine 10 mg; Group II, bupivacaine 10 mg + fentanyl 25 microg; Group III, bupivacaine 7.5 mg + fentanyl 25 microg; Group IV, bupivacaine 5 mg + fentanyl 25 microg. The final volume of intrathecal injectate was adjusted to 2. 5 mL with sterile distilled water. Spinal anesthesia was administered with the 27-gauge Whitacre needle at the L2-3 interspace with the patient in the sitting position. Neural block was assessed by using pinprick and a modified Bromage scale. The degree of motor block was more profound in Group II compared with Group I at the end of operation. In Group IV, there was no motor block at the end of operation in any of the patients. The median level of the upper limit of the sensory block was higher than T(7) in all groups before the start of surgery. The addition of 25 microg of fentanyl to 5 mg of bupivacaine resulted in short-acting motor block. When 25 microg of fentanyl was added to 10 mg of bupivacaine, it increased the intensity and duration of motor block. Only 5 (6. 3%) of the patients needed supplemental analgesia during the operation. ¿abs¿
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Analgésicos Opioides , Anestesia Raquidea , Anestésicos Locales , Bupivacaína , Fentanilo , Procedimientos Quirúrgicos Urológicos Masculinos , Anciano , Método Doble Ciego , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Bloqueo Nervioso , Estudios ProspectivosRESUMEN
The results of studies on the effect of volume, concentration or total dose of local anaesthetic on the spread of spinal anaesthesia are inconclusive. Most support the assumption that the total dosage is more important than the volume. We compared low-dose bupivacaine (6 mg) in 0.5% and 0.18% solutions as sole anaesthetic to achieve predominantly unilateral spinal anaesthesia for knee arthroscopy. Sixty patients were randomly allocated to two groups to receive either 1.2 ml 0.5% bupivacaine (6 mg) (n = 30) or 3.4 ml 0.18% hypobaric bupivacaine (6.1 mg) (n = 30). Drugs were administered at the L3-4 interspace with the patient in the lateral position. Patients remained in this position for 20 min before being turned supine for the operation. Spinal block was assessed by pinprick and modified Bromage scale and compared between the operated and nonoperated sides. No significant changes were found in the spread or duration of sensory or motor block (p > 0.05). The haemodynamic changes were also similar between the groups. The same pinprick level of analgesia, degree of motor block and duration of spinal anaesthesia was obtained with bupivacaine (6 mg) in low (1.2 ml) or high (3.4 ml) volumes.
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Anestesia Raquidea/métodos , Anestésicos Locales/administración & dosificación , Bupivacaína/administración & dosificación , Endoscopía , Articulación de la Rodilla/cirugía , Adulto , Anestésicos Locales/efectos adversos , Artroscopía , Bupivacaína/efectos adversos , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/efectos de los fármacos , Satisfacción del Paciente , Sensación/efectos de los fármacos , Factores de TiempoRESUMEN
The increasing use of ambulatory surgery requires methods of anaesthesia that allow patients to be discharged soon after the operation is completed. Spinal anaesthesia is usually simple and quick, and the incidence of post-spinal headache has been reduced by using non-cutting small-gauge needles. Limiting the spread of spinal anaesthesia, as long as it still provides analgesia for surgery, should reduce the haemodynamic effects and speed recovery. Restricted spinal anaesthesia, intended to be unilateral using 0.18% hypobaric bupivacaine via a 25G or 27G Whitacre unidirectional needle, was compared with epidural anaesthesia (using a mixture of lignocaine and prilocaine) in 64 matched-pair patients undergoing ambulatory arthroscopy. Motor blockade, assessed for the specific myotomes L2 to S1, was significantly more unilateral in the spinal group. Two patients in the spinal group and nine patients in the epidural group were treated for hypotension (P < 0.05). One patient in the spinal group developed a post-spinal headache. One patient in the epidural group rated the anaesthesia poor.
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Procedimientos Quirúrgicos Ambulatorios , Anestesia Raquidea , Adulto , Anestesia Epidural/efectos adversos , Anestesia Raquidea/efectos adversos , Anestesia Raquidea/métodos , Anestésicos Locales , Bupivacaína , Femenino , Humanos , Articulación de la Rodilla/cirugía , Lidocaína , Masculino , Persona de Mediana Edad , Proyectos Piloto , PrilocaínaRESUMEN
BACKGROUND AND OBJECTIVES: Ambulatory surgery requires anesthesia methods that allow rapid recovery and safe discharge of the patient. Spinal anesthesia is easy and quick to perform, and the use of noncutting small gauge needles reduces the occurrence of postdural puncture headache. For minimal hemodynamic consequences and faster recovery and discharge it would be optimal to limit the spread of spinal anesthesia only to the area which is necessary for surgery. In this study, the possibility in achieving unilateral spinal anesthesia with 0.18% hypobaric bupivacaine was studied. METHODS: Spinal anesthesia with 3.4 mL of hypobaric 0.18% bupivacaine (6.12 mg), without any intravenous infusion or prophylactic vasopressors, was administered with 27-gauge Whitacre unidirectional needle to 70 ASA I and II patients undergoing knee arthroscopies. The patients were allocated randomly to be kept either 20 (group I) or 30 (group II) minutes in the lateral position operation side uppermost. Sensory and motor block (pinprick/modified Bromage scale) were compared between the operation and the contralateral side. RESULTS: The motor and sensory block between operation and contralateral sides were significantly different at all testing times in both groups (P < .001, Mann-Whitney U test). The motor block was completely unilateral in 14 patients (39%) in group I and in 22 patients (65%) in group II. The hemodynamics were stable in all 70 patients. CONCLUSIONS: Approximately three and a half milliliters hypobaric 0.18% bupivacaine (6.12 mg) provides a predominantly unilateral spinal block. Thirty minutes spent in the lateral position does not provide benefits over 20 minutes. The main advantages of our method are the hemodynamic stability and the patient satisfaction.