Single shot spinal anaesthesia with hypobaric bupivacaine for hip fracture repair surgery in the elderly. Randomized, double blinded comparison of 3.75 mg vs. 7.5 mg.

BACKGROUND: Arterial hypotension is the most frequent adverse effect of subarachnoid anaesthesia in the elderly sustaining a femoral proximal fracture. Decreasing the local anaesthetic dose reduces the incidence of hypotension but shortens sensory block duration that could be insufficient in some surgical procedures. Sensory block duration could be prolonged using hypobaric local anaesthetics. We evaluated whether low hypobaric bupivacaine doses were adequate for this type of surgery while maintaining the haemodynamic stability. METHODS: A prospective, randomized, double blinded study was designed. Patients over 65 years old, sustaining traumatic hip fracture, were assigned to one of two groups: B0.5 group, hypobaric bupivacaine 7.5mg 5mg/ml (control group), and B0.25 group, hypobaric bupivacaine 3.75 mg 2.5mg/ml (study group). After subarachnoid injection, sensory level and motor blockade degree were registered, as were blood pressure, and heart rate at basal time and at 2, 5, 10, 15, 20 and 30 min after injection. The doses of vasopressor needed were registered as well. Surgical conditions and the duration of the surgical procedure-whether rescue analgesia or anaesthesia was needed-and sensory level regression to T12, were registered as well. RESULTS: Sixty four patients was the calculated sample size. The study was stopped in an interim analysis because an elevated number of patients in the B0.25 group needed iv rescue anaesthesia. In the analyzed cases, blood pressure was significantly lower in the B0.5 group at the 15 and 30 min measurements. Vasopressor drugs needs were similar between groups [ephedrine accumulated mean (SD) doses 11.4 (5.2) mg vs. 9.1 (2.7) mg, p=0.045)]. Sensory block regression to T12 was faster in the B0.25 group, [(mean (SD) 68.2 (29.0) min vs. 112.8 (17.3) min in the B0.5 group, p<0.05]. Five out of 19 patients in the B0.25 group needed intravenous anaesthesia rescue before surgery started. CONCLUSION: Lowering hypobaric bupivacaine dose to 3.75 mg in subarachnoid anaesthesia for hip fracture repair surgery in elderly patients decrease intraoperative blood pressure, but in an important number of patients intravenous anaesthesia rescue was needed and preclude recommendation.

Single shot spinal anesthesia with very low hyperbaric bupivacaine dose (3.75 mg) for hip fracture repair surgery in the elderly. A randomized, double blinded study.

PURPOSE: Single shot spinal anesthesia is used worldwide for hip fracture repair surgery in the elderly. Arterial hypotension is a frequent adverse effect. We hypothesized that lowering local anesthetics dose could decrease the incidence of arterial hypotension, while maintaining quality of surgical anesthesia. METHODS: In a randomized double blinded study, 66 patients over the age of 65 years, with hip fracture needing surgical repair, were assigned to B0.5 group 7.5mg hyperbaric bupivacaine 5mg/ml (control group), and B0.25 group 3.75mg hyperbaric bupivacaine 2.5mg/ml (study group). Sensory and motor block level, and hemodynamic parameters including blood presure, heart rate and vasopressor dose administration were registered, along with rescue anesthesia needs, the feasibility of surgery, its duration, and regression time of sensory anesthesia to T12. RESULTS: After exclusions, 61 patients were included in the final analysis. Arterial hypotension incidence was lower in the B0.25 group (at the 5, 10, and 15min determinations), and a lower amount of vasopressor drugs was needed (mean accumulated ephedrine dose 1.6mg vs. 8.7mg in the B0.5 group, p<0.002). Sensory block regression time to T12 was shorter in the B0.25 group, mean 78.6±23.6 (95% CI 51.7-110.2)min vs. 125.5±37.9 (95% CI 101.7-169.4)min in the B0.5 group, p=0.033. All but one patient in the B0.25 group were operated on under the anesthetic procedure first intended. No rescue anesthesia was needed. CONCLUSION: Lowering bupivacaine dose for single shot spinal anesthesia for hip fracture repair surgery in elderly patients was effective in decreasing the occurrence of arterial hypotension and vasopressor use, while intraoperative quality remained.

Awareness with recall during general anaesthesia: a prospective observational evaluation of 4001 patients.

BACKGROUND: We have prospectively evaluated the incidence and characteristics of awareness with recall (AWR) during general anaesthesia in a tertiary care hospital. METHODS: This study involves a prospective observational investigation of AWR in patients undergoing general anaesthesia. Blinded structured interviews were conducted in the postanaesthesia care unit, on postoperative day 7 and day 30. Definition of AWR was 'when the patient stated or remembered that he or she had been awake at a time when consciousness was not intended'. Patient characteristics, perioperative, and drug-related factors were investigated. Patients were classified as not awake during surgery, AWR, AWR-possible, AWR-not evaluable. The perceived quality of the awareness episode, intraoperative dreaming, and sequelae were investigated. The anaesthetic records were reviewed to search for data that might explain the awareness episode. RESULTS: The study included 4001 patients. Incidence of AWR was 1.0% (39/3921 patients). If high risk for AWR patients were excluded, the incidence was 0.8%. After the interview on the seventh day, six patients denied having been conscious during anaesthesia; hence, the incidence of AWR in elective surgery was 0.6%. Factors associated with AWR were: anaesthetic technique incidence of 1.1% TIVA-propofol vs 0.59% balanced anaesthesia vs 5.0% O2/N2O-based anaesthesia vs 0.9% other anaesthetic techniques (mainly propofol boluses for short procedures), P=0.008; age (AWR 42.3 yr old vs 50.6 yr old, P=0.041), absence of i.v. benzodiazepine premedication (P=0.001), Caesarean section (C-section) (P=0.019), and surgery performed at night (P=0.013). More than 50% of patients reported intraoperative dreaming in the early interview, mainly pleasant. Avoidable human factors were detected from the anaesthetic records of most patients. Subjective auditory perceptions prevailed, together with trying to move or communicate, and touch or pain perception. CONCLUSIONS: A relatively high incidence of AWR and dreams during general anaesthesia was found. Techniques without halogenated drugs showed more patients. The use of benzodiazepine premedication was associated with a lower incidence of AWR. Age, C-section with general anaesthesia, and surgery performed at night are risk factors.

[Bilateral axillary brachial plexus block guided by multiple nerve stimulation and ultrasound in a multiple trauma patient]. / Bloqueo axilar bilateral del plexo braquial guiado por neuroestimulación múltiple y ultrasonidos en una paciente con politraumatismo.

We present the case of a woman with multiple wounds and injuries after attempted suicide by jumping from a high place. She had multiple craniofacial injuries and fractures of both forearms requiring emergency osteosynthesis. The neurosurgeons requested that a level of consciousness be maintained for frequent assessment; therefore it was decided to provide a bilateral axillary brachial plexus block. The procedure was carried out with the aid of a nerve stimulator to locate a triple response in the left arm (radial, medial and musculocutaneous nerves) and with both ultrasound and double nerve stimulation in the right arm (medial and radial nerves). Surgery proceeded without adverse events. The location of nerves or nerve roots with both ultrasound and stimulators was highly useful in this patient in need of bilateral brachial plexus blockade. This combination, and ultrasound in particular, might be the technique of choice because it offers an image in real time and assessment of the least amount of anesthetic that seems to be needed for achieving a block.

Splenic rupture and haemoperitoneum in a patient with non-compaction of the left ventricular myocardium.

The anaesthetic and critical care management of blunt abdominal trauma in a patient previously diagnosed with non-compaction of the left ventricular myocardium (a rare autosomal dominant inherited disease) is reported. The management was influenced by the presence of an implanted automated internal defibrillator and treatment with anticoagulants because of the high frequency of severe arrhythmias and systemic embolism. The pathophysiology of ventricular non-compaction is reviewed briefly.

[Ketamine for subarachnoid anesthesia during hypovolemia: preliminary study in pigs]. / Utilización de ketamina para anestesia subaracnoidea durante hipovolemia. Estudio experimental preliminar en cerdos.

OBJECTIVES: To assess whether subarachnoid ketamine has fewer hemodynamic effects than lidocaine in normal and hypovolemic pigs and to determine whether or not the effects of ketamine are dose-dependent. METHODS: Thirty pigs were randomly allocated to receive subarachnoid administration of lidocaine 2 mg x kg(-1), ketamine 1 mg x kg(-1) or ketamine 2 mg x kg(-1), in a situation of either normal or reduced blood volume. The pigs were assigned to six groups: group L2 (2% lidocaine 2 mg x kg(-1), normovolemia), group L2H (2% lidocaine 2 mg x kg(-1), hypovolemia), group K1 (ketamine 1 mg x kg(-1), normovolemia), group K1H (ketamine 1 mg x kg(-1), hypovolemia), group K2 (ketamine 2 mg.kg(-', normovolemia), and group K2H (ketamine 2 mg x kg(-1), hypovolemia). To induce hypovolemia 30% of the calculated blood volume was withdrawn from each pig. The subarachnoid space was catheterized, and invasive measurements of hemodynamic variables (derived from arterial, central venous and pulmonary artery catheter monitoring) were obtained. Variables were recorded at baseline and 5 and 15 min after drug injection in the normovolemic groups, and at baseline after inducing hypovolemia and 5 and 15 min after drug injection in the hypovolemic groups. RESULTS: In the normovolemic pigs no significant differences were detected between groups. In hypovolemic pigs differences were observed in heart rate and arterial pressure between the ketamine 1 mg x kg(-1) and lidocaine 2 mg x kg(-1) groups (P < 0.05). The decreases in heart rate and arterial pressure were less marked in the ketamine group. Mixed venous oxygen saturation and cardiac index deteriorated to a lesser degree in both ketamine groups than in the lidocaine groups (P < 0.05). CONCLUSIONS: Racemic ketamine administered by subarachnoid injection in hypovolemic pigs produces less deterioration in hemodynamic variables than does lidocaine. Hemodynamic changes caused by ketamine were not dose-dependent. These findings may be of interest, given the increased use of ketamine in neuroaxial anesthesia and analgesia and perhaps the possible use of neuroaxial ketamine in hypovolemic patients.

[Spinal and cerebral hematoma following diagnostic lumbar puncture with fatal course]. / Hematoma espinal y cerebral postpunción lumbar diagnóstica con evolución letal.

A 64-year-old man suspected of having neurosyphillis suffered subarachnoid spinal and cerebral ventricular hemorrhage after a diagnostic lumbar puncture. The main risk factor was trauma occurring during a difficult puncture. Both the diagnosis and the subsequent laminectomy were delayed. Blood migrated to both lateral ventricles, complicating the clinical course, which ended in death. The need for rapid diagnosis and treatment in such cases is revealed by both images and clinical course. A pathophysiologic explanation for these hemorrhagic events is provided.