Fluid management is an important component of perioperative care for patients undergoing neurosurgery. The primary goal of fluid management in neurosurgery is the maintenance of normovolemia and prevention of serum osmolarity reduction. To maintain normovolemia, it is important to administer fluids in appropriate amounts following appropriate methods, and to prevent a decrease in serum osmolarity, the choice of fluid is essential. There is considerable debate about the choice and optimal amounts of fluids administered in the perioperative period. However, there is little high-quality clinical research on fluid therapy for patients undergoing neurosurgery. This review will discuss the choice and optimal amounts of fluids in neurosurgical patients based on the literature, recent issues, and perioperative fluid management practices.

No abstract available.
Colorectal Surgery*

Traditionally, Ketamine has been considered to be contraindicated in neurosurgical patients due to the risk of intracranial hypertension. The evidence for this contraindication originated from early case reports and case-control studies which were inadequately designed and controlled. However, several recent articles indicate that ketamine can be safely used in traumatic brain injured patients treated with mechanical ventilation and that there is no significant increase in the intracranial pressure (ICP). Ketamine is an N-methyl-D-aspartate antagonist. It is believed to provide neuroprotection through a reduction in the glutamate excitotoxicity. This evidence is based on in vitro and animal studies. However, studies about its neuroprotective effects in humans are scarce. Data to recommend ketamine as first-line anesthetics for neurosurgery are insufficient, but ketamine as an adjuvant anesthetic agent may have benefits for neurosurgical patients, such as traumatic head injured patients with unstable hemodynamics. Therefore, ketamine should not be considered as absolutely contraindicated for neurosurgical patients and adequately powered, high-quality randomized controlled studies are needed to provide clinical evidences.
Anesthesia* ; Anesthetics ; Animals ; Brain ; Brain Injuries ; Case-Control Studies ; Glutamic Acid ; Head ; Hemodynamics ; Humans ; Intracranial Hypertension ; Intracranial Pressure ; Ketamine* ; N-Methylaspartate ; Neuroprotective Agents ; Neurosurgery ; Respiration, Artificial

Anesthesiologists frequently see asymptomatic patients with diastolic dysfunction or heart failure for various surgeries. These patients typically show normal systolic function but abnormal diastolic parameters in their preoperative echocardiographic evaluations. The symptoms that are sometimes seen are similar to those of chronic obstructive pulmonary disease. Patients with diastolic dysfunction, and even with diastolic heart failure, have the potential to develop a hypertensive crisis or pulmonary congestion. Thus, in addition to conventional perioperative risk quantification, it may be important to consider the results of diastolic assessment for predicting the postoperative outcome and making better decisions. If anesthesiologists see female patients older than 70 years of age who have hypertension, diabetes, chronic renal disease, recent weight gain, or exercise intolerance, they should focus on the patient's diastologic echocardiography indicators such as left atrial enlargement or left ventricular hypertrophy. In addition, there is a need for perioperative strategies to mitigate diastolic dysfunction-related morbidity. Specifically, hypertension should be controlled, keeping pulse pressure below diastolic blood pressure, maintaining a sinus rhythm and normovolemia, and avoiding tachycardia and myocardial ischemia. There is no need to classify these diastolic dysfunction, but it is important to manage this condition to avoid worsening outcomes.
Blood Pressure ; Echocardiography ; Estrogens, Conjugated (USP) ; Female ; Heart Failure* ; Heart Failure, Diastolic ; Heart* ; Humans ; Hypertension ; Hypertrophy, Left Ventricular ; Myocardial Ischemia ; Pulmonary Disease, Chronic Obstructive ; Renal Insufficiency, Chronic ; Tachycardia ; Weight Gain

BACKGROUND: Direct puncture by a needle is a risk factor for nerve damage. This study was designed to demonstrate nerve damage caused by a needle using the synchrotron small-angle X-ray scattering (SAXS) technique. METHODS: A 15 mm section of rat (Male Spargue-Dawley, about 250 grams) sciatic nerves were involved in this study. The nerve specimen for the experiment (N = 5) was punctured 5 times by a needle (25 G, 100 beveled) under general anesthesia with enflurane. The needle was placed perpendicular to the nerve and the needle bevel was placed parallel to the nerve. The SAXS patterns of the punctured nerves, extracted about 15 min prior to the experiment, were acquired after 1 week. The SAXS patterns of a normal sciatic nerve (N = 5), extracted about 15 min prior to the experiment, were measured in order to provide a comparison. Experiments were carried out at 4C1 beamline at Pohang Accelerator Laboratory in Korea. Incoming X-rays were monochromatized at 11 keV using a double multilayer (WB4C) monochromator; the beam size was around 0.5 (V) x 0.8 (H) mm2. The exposure time was 60 sec, and 8 to 12 images were acquired per sample with a 0.5 mm interval. RESULTS: In the punctured group, the periodic peaks of myelin sheath and collagen fiber were not changed. However, the periodic peaks of interfibrillar distance of collagen were greatly changed. CONCLUSIONS: Direct needle-nerve impalement did not cause damages in myelin sheath and collagen fibers when the needle was placed perpendicular and the needle bevel paralleled to the nerve fiber. This result can imply that the needle slipped into the interfibrillar packing of collagen fibrils.
Anesthesia, General ; Animals ; Collagen ; Enflurane ; Gyeongsangbuk-do ; Korea ; Myelin Sheath ; Needles* ; Nerve Fibers ; Peripheral Nerve Injuries* ; Punctures ; Rats* ; Risk Factors ; Sciatic Nerve* ; Synchrotrons*

BACKGROUND: Pain on injection of rocuronium is a common clinical problem. We compared the efficacy of lidocaine, ketorolac, and the 2 in combination as pretreatment for the prevention of rocuronium-induced withdrawal movement. METHODS: For this prospective, randomized, placebo-controlled, double-blind study a total of 140 patients were randomly allocated to one of 4 treatment groups to receive intravenously placebo (saline), lidocaine (20 mg), ketorolac (10 mg), or both (n = 35 for each group), with venous occlusion. The tourniquet was released after 2 min and anesthesia was performed using 5 mg/kg thiopental sodium followed by 0.6 mg/kg rocuronium. The withdrawal response was graded on a 4-point scale in a double-blind manner. RESULTS: The overall incidence of withdrawal movements after rocuronium was 34.3% with lidocaine (P = 0.001), 40% with ketorolac (P = 0.004), and 8.6% with both (P < 0.001), compared with 74.3% with placebo. There was a significantly lower incidence of withdrawal movements in patients receiving the lidocaine/ketorolac combination than in those receiving lidocaine or ketorolac alone (P = 0.009 and 0.002, respectively). The incidence of moderate to severe withdrawal movements was 14.3% with lidocaine, 17.2% with ketorolac, and 2.9% with lidocaine/ketorolac combination, as compared to 45.7% with the placebo. There was no significant difference in withdrawal movement between the lidocaine group and the ketorolac group. CONCLUSIONS: Ketorolac pretreatment had an effect comparable to that of lidocaine in attenuating rocuronium-induced withdrawal movements and the lidocaine/ketorolac combination pretreatment, compared with lidocaine or ketorolac alone, effectively reduced withdrawal movements during rocuronium injection.
Androstanols ; Anesthesia ; Double-Blind Method ; Humans ; Incidence ; Ketorolac ; Lidocaine ; Prospective Studies ; Thiopental ; Tourniquets

BACKGROUND: During general anesthesia, a heated breathing circuit (HBC) is used to replace the heat and moisture exchange function of the upper airway. One HBC uses an air dryer filter that employs silica gel (SG) as a desiccant. SG is capable of adsorbing many organic compounds. Therefore, we undertook an in vitro study of the adsorption of desflurane by SG filters. METHODS: An HBC was connected to an anesthesia machine, and a test lung was connected to the circuit. The test lung was mechanically ventilated with 2 or 4 L/min of fresh gas flow, with and without the air dryer filter. Desflurane was administered at a 6 vol% on the vaporizer dial setting. The experiment was repeated 15 times in each group. The end-tidal concentrations were measured during the experiments. The air dryer filter weights were measured before and after the experiments, and the times required to achieve the specific end-tidal desflurane concentrations were determined. RESULTS: Significant differences in the end-tidal concentrations of desflurane were observed between the control and filter groups (P < 0.001). The filter weights increased significantly after the experiments (P < 0.001). The times required to achieve the same end-tidal desflurane concentrations were different with the application of the air dryer filter (P < 0.001). CONCLUSIONS: The adsorption of desflurane with the use of an air dryer filter was verified in this in vitro study. Careful attention is needed when using air dryer gel filters during general anesthesia.
Adsorption* ; Air Filters ; Anesthesia ; Anesthesia, General ; Desiccation ; Hot Temperature ; Lung ; Nebulizers and Vaporizers ; Respiration* ; Silica Gel* ; Weights and Measures

A 59-year-old woman was scheduled to undergo a robot-assisted distal gastrectomy under general anesthesia. During the operation, the vital signs were maintained in normal range. After 7 hours of surgery, the pulse oxymeter graph became flat and the end tidal CO2 concentration suddenly decreased. Palpation of the carotid artery revealed no heart beat but the EKG continued to show sinus rhythm. Pulseless electrical activity (PEA) was diagnosed. An advanced cardiopulmonary life support protocol for PEA was immediately initiated, which included chest compressions and doses of IV cardiovascular drugs. However, in spite of continuous CPR, the heart wasn't recovered from the arrest. We experienced cardiac arrest for pulseless electrical activity during robot-assisted distal gastrectomy.
Anesthesia, General ; Cardiopulmonary Resuscitation ; Cardiovascular Agents ; Carotid Arteries ; Electrocardiography ; Female ; Gastrectomy ; Heart ; Heart Arrest ; Humans ; Hypovolemia ; Middle Aged ; Palpation ; Peas ; Reference Values ; Thorax ; Vital Signs

BACKGROUND: Spinal anesthesia causes hypotension and bradycardia due to sympathetic nerve block and it is difficult to predict the level of sensory block and the duration of blockade. Recent studies have reported that intravenous phenylephrine can reduce the rostral spread of spinal anesthesia in pregnant women. We think a phenylephrine infusion will be useful for maintaining the baseline blood pressure by reducing the rostral spread of spinal anesthesia during the elective surgery of non-obstetric patients. METHODS: Sixty patients who were undergoing urologic surgery were randomized into two groups: Group C (the control group without phenylephrine) and Group P (with the addition of phenylephrine). After a bolus infusion of 50 microg phenylephrine following the spinal injection, phenylephrine was continuously infused at the rate of 200 microg/hr. We compared the dermatomal spreads of spinal anesthesia, the hemodynamic parameters (blood pressure, heart rate) and the incidences of hypotension between the two groups. RESULTS: At 20 minutes, the level of the upper dermatome blocked against cold sensation was a median of T8 (interquartile range: T8-T10) for the phenylephrine group, as compared with T4 (interquartile range: T4-T6) for the control group (P < 0.001). CONCLUSIONS: Intravenous phenylephrine can decrease the rostral spread of spinal anesthesia during urologic surgery.
Anesthesia, Spinal ; Autonomic Nerve Block ; Blood Pressure ; Bradycardia ; Cold Temperature ; Female ; Heart ; Hemodynamics ; Humans ; Hypotension ; Incidence ; Injections, Spinal ; Phenylephrine ; Pregnant Women ; Sensation