Anaesthesia For Minor Surgery Research Articles

Comparison Between Hypnoanesthesia and Local Anesthesia in Minor Surgery

Background: Hypnoanesthesia is a state of anesthesia achieved through hypnosis techniques. Meanwhile, local anesthesia is anesthesia carried out by injecting local anesthetic drugs in or around the surgical site which causes temporary obstruction to the conduction of afferent impulses. Objective: This research was conducted to prove that there is no difference between hypnoanesthesia and local anesthesia in minor surgical procedures, with the indication of pain relief. Methods: The research subjects were patients with benign soft tissue tumors consisting of 40 people who were divided into 2 groups, namely treatment and control. Minor surgical procedures with hypnoanesthesia were performed in the treatment group, while in the control group, minor surgical procedures were performed with local anesthesia using 2% lidocaine. Pain is measured with FPS (Face Pain Scale) and monitored with a vital sign monitor. The intervention process was recorded with camcorder video. Changes in serum levels of excitatory neurotransmitters (Glutamic Acid and Substance P) and inhibitory (Beta Endorphin, Enkephalin, and Serotonin) before and after intervention were analyzed using ELISA (Enzym-Link Immunosorbent Assay) in both groups. Results: In the treatment group, it was discovered that patients did not feel pain after undergoing hypnoanesthesia intervention by providing suggestions for the relief of pain in the area where surgery would be performed. In the control group, patients also did not feel pain after local anesthetic intervention in the area to be operated on. However, the results of research and statistical tests showed that there was no significant difference in changes in Beta Endorphins, Enkephalin, and Serotonin as inhibitory neurotransmitters (p > 0.05) or Glutamic Acid and Substance P as excitatory neurotransmitters (p > 0.05) before and after the intervention in both groups of research subjects. Conclusion: the results of this study show that there is no significant difference between the treatment and control groups, they have equality in the final result, namely the relief of pain.

Anaesthesia for minor surgery in oral cancer: a review

Anaesthesia for minor surgery in oral cancer: a review

Updates on Wound Infiltration Use for Postoperative Pain Management: A Narrative Review.

Local anesthetic wound infiltration (WI) provides anesthesia for minor surgical procedures and improves postoperative analgesia as part of multimodal analgesia after general or regional anesthesia. Although pre-incisional block is preferable, in practice WI is usually done at the end of surgery. WI performed as a continuous modality reduces analgesics, prolongs the duration of analgesia, and enhances the patient’s mobilization in some cases. WI benefits are documented in open abdominal surgeries (Caesarean section, colorectal surgery, abdominal hysterectomy, herniorrhaphy), laparoscopic cholecystectomy, oncological breast surgeries, laminectomy, hallux valgus surgery, and radical prostatectomy. Surgical site infiltration requires knowledge of anatomy and the pain origin for a procedure, systematic extensive infiltration of local anesthetic in various tissue planes under direct visualization before wound closure or subcutaneously along the incision. Because the incidence of local anesthetic systemic toxicity is 11% after subcutaneous WI, appropriate local anesthetic dosing is crucial. The risk of wound infection is related to the infection incidence after each particular surgery. For WI to fully meet patient and physician expectations, mastery of the technique, patient education, appropriate local anesthetic dosing and management of the surgical wound with “aseptic, non-touch” technique are needed.

Časná poporodní anestezie v České a Slovenské republice z pohledu studie OBAAMA-INT - prospektivní observační studie

Časná poporodní anestezie v České a Slovenské republice z pohledu studie OBAAMA-INT - prospektivní observační studie

Infiltracija hirurške rane lokalnim anestetikom - infiltracija rane

A large number of surgical interventions are performed ambulatory under local infiltrative anesthesia. Local anesthetic wound infiltration provides anesthesia for minor surgical procedures and perioperatively improves analgesia after surgery in general anesthesia as part of a multimodal analgesic approach. The effect of a single block wound infiltration at the end of a surgical procedure in general or regional anesthesia provides additional analgesia for several hours. Infiltrative local anesthesia performed in a continuous modality reduces the use of analgesics, prolongs duration of analgesia and enhances the patient's mobilization. Benefits of local infiltrative anesthesia are described in inguinal hernioplasty, breast surgery, sternotomy, orthopedic, and gynecological surgery. However, in abdominal surgery, continuous infiltrative local anesthesia is combined with other analgesic modalities respecting complex innervation of the abdominal wall and intra-abdominal organs,. Wound infiltration is a safe technique without the risk of surgical wound infection. There is a lack of data about cost-benefit ratio when wound infiltration is used. In order for local infiltrative anesthesia to fully meet the expectations it is necessary to have mastery of the relatively simple technique, and the knowledge of when it is suitable to appply.

Safe Anesthesia for Minor Surgical Procedures without Venous Cannulation in Healthy Children-864 Cases

Introduction Establishing intravenous IV access is customary for patients undergoing general anesthesia especially in the pediatric population Obtaining reliable vascular access in small children is frequently made challenging Pediatric patients are often less co operative and prone to develop psychological trauma Though general anesthesia without IV access is safe for healthy pediatric patients undergoing simple and brief procedure However it is not encouraged to anesthetize children with complex medical conditions without IV access especially for long durations of general anesthesia Purpose The objective of this study was to examine complications amp risk following pediatric short surgical procedures under anesthesia without IV placement Methods This observational study was carried out in Combined Military Hospital Dhaka among children of different age ranging from to years This study was conducted among children scheduled for the elective short surgical procedures under general anesthesia with spontaneous ventilation having American Society of Anesthesiologists ASA grade I amp II during the period of May to Feb The total number of anesthetics and rescued IV placements were identified Patient characteristics length of the procedure laryngeal mask airway LMA placement and complications like desaturation laryngospasm secretion amp bleeding related risk of aspirations were recorded Results patients were included in this study over a period of years Out of the cases only patients required rescue and or elective IV placement and significantly cases were performed safely without IV access In of the cases anesthetics were administered with a laryngeal mask airway LMA out of which a large proportion of cases did not have IV access Among the total number of patients only developed transient desaturation and developed laryngospasm Out of the transient desaturation patients required rescue LMA in an attempt to manage airway There were only complications among cases all of which were resolved safely There were no incidence of deaths or prolong admissions for complications Conclusion The study was conducted over years with cases recorded During this study almost of cases were performed successfully and thus illustrates that it is safe to perform short surgical procedures under general anesthesia without securing IV access All emergency post complications IV placements were successful Perioperative complications were resolved safely where no long term sequelae were seen

Comparative study of midazolam, dexmedetomidine, and ketamine as an adjuvant to lidocaine in intravenous regional anesthesia for forearm and hand surgeries

Background Intravenous regional anesthesia (IVRA) is an ideal method of providing anesthesia for minor surgical procedures to the extremities performed on an ambulatory basis. This study aimed to study the effects of adding midazolam, dexmedetomidine, or ketamine as an adjuvant to lidocaine in IVRA during forearm and hand surgeries and examine their benefits and complications. Patients and methods A total of 120 patients were included, aged 40–60 years (American Society of Anesthesiologists physical status I–II), undergoing hand and forearm, from April 2015 to August 2016. Patients were randomly divided into four equal groups. Lidocaine-only group (LL group) received IVRA using 40 ml of lidocaine 0.5% (3 mg/kg). Lidocaine plus midazolam group (LM group) received IVRA using 40 ml of lidocaine 0.5% (3 mg/kg) plus midazolam 50 µg/kg added as an adjuvant. Lidocaine plus dexmedetomidine group (LD group) received IVRA using 40 ml of lidocaine 0.5% (3 mg/kg) plus dexmedetomidine 1 µg/kg added as an adjuvant. Lidocaine plus ketamine group (LK group) received IVRA using 40 ml of lidocaine 0.5% (3 mg/kg) plus ketamine 0.5 mg/kg added as an adjuvant. The time of onset, duration, and quality of analgesia; levels of sensory and motor block; heart rate; mean arterial blood pressure; and visual analog score were recorded. Adverse effects of hematoma, injection pain, skin erythema, sedation, and hallucinations were recorded. Results The onset time of sensory and motor blocks was significantly shorter in the adjuvant groups LM, LD, LK in comparison with the control group LL. The grade of sensory and motor blocks was significantly better in groups LM, LD, and LK in comparison with the LL group. The onset time of tourniquet pain was significantly shorter in the control group LL in comparison with adjuvant groups LM, LD, and LK. There was a significant increase in fentanyl requirements in the control LL group compared with adjuvant LM, LD, and LK groups. The duration of postoperative analgesia was significantly prolonged in adjuvant groups LM, LD, and LK compared with the control LL group. Hematoma, injection pain, cutaneous erythema, and hallucination were reported as postoperative complications. Conclusion The addition of midazolam, dexmedetomidine, or ketamine to lidocaine for IVRA improved the quality of intraoperative and postoperative analgesia with minimal adverse effects and higher patients and surgeon satisfaction.

A pilot study to determine whether visually evoked hemodynamic responses are preserved in children during inhalational anesthesia.

Anesthetic depth is an important parameter to monitor during surgery, yet remains difficult to quantify, particularly in young children where developmental changes influence the electroencephalogram. A more fundamental physiological response to stimulation is the increase in cerebral blood flow secondary to increased metabolic demand, referred to as flow-metabolism coupling (FMC) and measurable using near-infrared spectroscopy (NIRS). Little is known about the effect of anesthesia on FMC; therefore, we studied visually evoked hemodynamic responses (VEHRs) using NIRS in children undergoing general anesthesia for minor surgical procedures. We recruited 23 children (aged 2-5years), undergoing surgery requiring general anesthesia. VEHRs were measured for 30min using NIRS, including 5min of baseline recording after anesthetic induction. Parameters recorded using NIRS included the concentrations of oxygenated (oxy), deoxygenated (deoxy), and total hemoglobin (Hb), which were separated into epochs for evoked response analysis after filtration of motion artifact and baseline drift. Goodness-of-fit statistics and classification rules were used to determine the existence of evoked responses, and a modified Gaussian equation was used to model each evoked response. Near-infrared spectroscopy data were recorded in 20/23 children, of whom nine showed a VEHR. No responses were seen in the baseline control data. When examining the relationship between VEHR and anesthetic agents, we noted that for 8/10 patients in whom preoperative or intraoperative fentanyl were administered and VEHRs were absent. We have shown that VEHRs can be detected using NIRS in some anesthetized children. Administration of fentanyl was associated with an absence of VEHRs. The mechanism underlying this association is unclear.

Season of Sampling and Season of Birth Influence Serotonin Metabolite Levels in Human Cerebrospinal Fluid

BackgroundAnimal studies have revealed seasonal patterns in cerebrospinal fluid (CSF) monoamine (MA) turnover. In humans, no study had systematically assessed seasonal patterns in CSF MA turnover in a large set of healthy adults.Methodology/Principal FindingsStandardized amounts of CSF were prospectively collected from 223 healthy individuals undergoing spinal anesthesia for minor surgical procedures. The metabolites of serotonin (5-hydroxyindoleacetic acid, 5-HIAA), dopamine (homovanillic acid, HVA) and norepinephrine (3-methoxy-4-hydroxyphenylglycol, MPHG) were measured using high performance liquid chromatography (HPLC). Concentration measurements by sampling and birth dates were modeled using a non-linear quantile cosine function and locally weighted scatterplot smoothing (LOESS, span = 0.75). The cosine model showed a unimodal season of sampling 5-HIAA zenith in April and a nadir in October (p-value of the amplitude of the cosine = 0.00050), with predicted maximum (PCmax) and minimum (PCmin) concentrations of 173 and 108 nmol/L, respectively, implying a 60% increase from trough to peak. Season of birth showed a unimodal 5-HIAA zenith in May and a nadir in November (p = 0.00339; PCmax = 172 and PCmin = 126). The non-parametric LOESS showed a similar pattern to the cosine in both season of sampling and season of birth models, validating the cosine model. A final model including both sampling and birth months demonstrated that both sampling and birth seasons were independent predictors of 5-HIAA concentrations.ConclusionIn subjects without mental illness, 5-HT turnover shows circannual variation by season of sampling as well as season of birth, with peaks in spring and troughs in fall.

Heated Moisture Exchanger (HME) and dead space ventilation. Is Isocapnic conditions unachievable in children?

Pulmonary dead space under general paediatric anaesthesia is a useful and relevant parameter [1]. We know that Heated Moisture Exchanger (HME) may lead to larger dead space and can negatively impact mechanical ventilation and gas exchange [1,2]. Smaller HME appears to be preferable, but there is a lack of information regarding their applicability and suitability in paediatric population [2]. On this issue, Kwon [3] analyzed the effects of HME on dead space in 20 relatively healthy paediatric patients, during their exposure to general anaesthesia for minor surgical procedures. We would like to congratulate the authors on their original hypothesis and results, which have clinical crucial implications. They reported that PaCO2 was significantly influenced by HME and the difference was correlated with weight (P < 0.001) and age (P = 0.002) of a patient. However, some major considerations and questions should be taken into consideration for the definitive clinical implications of their results. Firstly, clinical consequences of the removal of HME for 15 minutes without compensatory use of another artificial humidification may lead to serious implications, such as cilia and endothelial injury, increase in airway resistance, hypothermia, and etc. [2,4]. We have not been provided with any information in regards to these well known consequences, as well as whether or not any attempt was made to measure such complications. Secondly, there is insufficient information on the baseline of mechanical ventilation in both situations, which may influences our interpretation of higher pCO2 levels [4]. We have no information regarding the airway resistance, compliance, or peak airway pressure, which could help us for a better interpretation [5]. It would have been important to know the difference in PaCO2 between the baseline and after experimentation rather than just knowing the difference at the end of the experiment [3,4]. It is hard to determine whether or not the reduction is temporal and not a direct influence. Thirdly, main thrust of this report is on the alteration in physiological variables rather than clinically important outcomes, such as length mechanical ventilation or influence on weaning [5]. Overall, this report does not answer what are clinically impor tant questions, such as which device is better for humidifi cation, what effects of clinically important outcomes can be derived from this experiment and how best to use humidification without causing lung injury. In our opinion, this attractive and original report fails to even bridge a tile in this puzzle of humidification during healthy pediatric anesthesia.

The effect of timing and temperature of oral fluids ingested after minor surgery in preschool children on vomiting: a prospective, randomized, clinical study

The time at which children should resume oral intake after surgery is controversial. No information has been published about the relationship between postoperative vomiting and the temperature of the fluid ingested. This study was designed to analyze the effect on postoperative vomiting of the timing and temperature of the fluids ingested in the first oral intake. Two hundred and thirty-seven male children aged 2-7 years, scheduled for correction of inguinal hernia or undescended testis under general anesthesia and were allocated into four groups. The patients in groups C1 and C2 received clear fluids at room temperature or at body temperature, respectively, 2 h after emergence. The patients in groups E1 and E2 received clear fluids at room temperature or at body temperature, respectively, 1 h after emergence. Vomiting was assessed at intervals of 30 min for 6 h postoperatively, starting from 10 min after emergence. The incidence of vomiting was higher in groups C1 (25%) (P = 0.016) and E1 (26.7%) (P = 0.011) than in groups C2 (6.9%) and E2 (10.2%). The incidence was found to be increased significantly 40 min after oral intake in groups C1 (P = 0.012) and E1 (P = 0.010) compared with earlier measurements in the same groups. A first oral intake in children 1 h after anesthesia for minor surgery seems not to increase the incidence of vomiting as long as the ingested fluid is at body temperature.

Tumescent technique in digits: a subcutaneous single-injection digital block

BackgroundA modified subcutaneous single-injection approach to achieve digital block using a tumescent technique is described. MethodA convenient sample of patients requiring digital anesthesia for minor surgical procedures on the fingers or thumb in the emergency and plastic departments were enrolled into the study. Digital nerve block was performed by injecting 1% lidocaine into the volar subcutaneous space at the proximal digit to create a firm, turgid feel to the tissue, the so-called tumescent state. The volume of anesthetic was based on the size of the digit. All nerve blocks were performed by 1 surgeon. Successful digital anesthesia was defined as complete loss of pinprick sensation on both the dorsal and volar aspects of the digit and the ability to complete the anticipated minor surgical procedure without pain. All patients were followed for 1 month to assess for adverse events. ResultBetween August 2009 and January 2011, 123 patients (123 digits) requiring digital anesthesia were enrolled into the study. Thirty-nine (32%) were volar lesions, and 84 (68%) were dorsal lesions. The tumescent technique single-injection digital block was successful in all digits. No adverse events were reported. ConclusionThe tumescent technique in digits to achieve a single-injection digital nerve block is an easy, safe and effective method for digital anesthesia. These data confirm the applicability of the tumescent technique in digits for patients with finger and thumb injuries or tumors that require minor surgical procedures.

Comparison of ketamine-diazepam with ketamine-xylazine anesthetic combinations in sheep spontaneously breathing and undergoing maxillofacial surgery

The objective of this study was to choose a suitable anesthetic combination for use in experimental surgical models by comparing the anesthetic and cardio-respiratory changes. Fourteen healthy male sheep were randomly assigned to two different drug regimens. In Group 1 the sheep were anesthetized with ketamine + xylazine (22 mg/kg im. + 0.2 mg/kg i.m., respectively). Anesthetic combination of ketamine + diazepam (22 mg/kg im. + 0.4 mg/kg i.m., respectively) was used in Group 2. Heart rate, respiratory rate and mean arterial pressures were evaluated before anesthesia, after induction of anesthesia up to 30 minutes in 5 minute intervals and during recovery. In all sheep, duration of anesthesia induction, duration of anesthesia and duration of recovery were recorded. Quality of induction, anesthesia, analgesia and recovery were evaluated. Cardio-respiratory parameters decreased below baseline values after anesthesia induction in both groups. However, no profound effects on cardio-respiratory functions were observed during study. In Group 2, it was observed that; anesthesia induction time was longer, the depth of anesthesia was inadequate during the osteotomy stage of the surgical procedure and recovery time was longer in comparison to Group 1. Otherwise the quality of anesthesia induction, anesthesia, analgesia and recovery was better in Group 1 than Group 2. These findings indicate that both drug combinations can provide short time anesthesia for minor surgical procedures. Ketamine+xylazine combination can be used as a more suitable anesthetic combination in experimental surgical procedures such as maxillofacial surgery than ketamine+diazepam combination, in sheep.

Evaluation of a Transthecal Digital Nerve Block in the Injured Pediatric Patient

Digital anesthesia in the pediatric population has traditionally been accomplished using a ring block that requires multiple injections. A modified transthecal digital nerve block is a single-injection technique of the midproximal phalanx that has been shown to be technically simple and highly effective in adults. To describe the success rate of the modified transthecal digital nerve block in children. : A convenience sample of children requiring digital anesthesia for minor surgical procedures on the fingers or thumb at an urban tertiary-care pediatric emergency department were prospectively enrolled into the study. A transthecal digital nerve block was performed by injecting a 1:1 mixture of 1% lidocaine and 0.5% bupivicaine into the flexor tendon sheath at the midpoint between the proximal digital and the proximal interphalangeal joint creases. The volume of anesthetic was based on age. All nerve blocks were performed by 3 investigators trained in the procedure. Successful digital anesthesia was defined as complete loss of pinprick sensation on both the dorsal and palmar aspects of the digit and the ability to complete the anticipated minor surgical procedure without pain. Primary outcome measures were anesthesia success rate and pain score. Age-appropriate pain scale scores (Face, Legs, Activity, Cry, Consolability Scale, 0-3 years; Faces Scale, 4-7 years; and visual analog scale, > or =8 years) were recorded 5 minutes after injection. All patients were followed up for 6 months to assess for adverse events. Between November 2003 and March 2004, 48 patients (50 digits) requiring digital anesthesia were enrolled into the study. The mean age of patients was 8.3 years (median, 7.6 years; range, 0.7-17.5 years). Twenty-four (50%) were boys and 30 whites (62.5%). Overall, the transthecal digital nerve block technique was successful in 47 (94%) of the 50 digits (95% confidence interval [CI], 83%-98%), including 37 (97%) of 38 fingers (95% CI, 85%-99%) and 10 (83%) of 12 thumbs (95% CI, 54%-96%). Forty-seven (94%) of the 50 digits had a recorded pain score of 0 five minutes after injection. Mean (SD) procedure time was 113 (24.8) seconds, and mean (SD) anesthetic volume was 2.13 (0.61) mL. No adverse events were reported. The single-injection modified transthecal digital nerve block is a safe and effective method for digital anesthesia in children. These data confirm the applicability of transthecal digital nerve block for children with finger and thumb injuries that require minor surgical procedures.

Doppler transcraneal, BIS y entropía como medición indirecta del flujo cerebral durante la anestesia inhalatoria en pacientes pediátricos

Transcranial Doppler ultrasound is a noninvasive technique for monitoring the velocity of blood flow in the main intracranial arteries, particularly those in the circle of Willis. Our aim was to assess whether changes in cerebral arterial blood flow in pediatric patients under sevoflurane anesthesia demonstrated by pulsed Doppler ultrasound correlate with changes in the bispectral (BIS) index and electroencephalographic state and response entropy (ES and ER, respectively). Prospective, blinded observational study of 36 pediatric patients (age range, 5 to 11 years; ASA physical status classification, 1-2) under sevoflurane anesthesia for minor surgical procedures. Anesthesia was induced with sevoflurane and maintained with 2.5% sevoflurane in an inspired oxygen fraction of 50% in air. A continuous perfusion of remifentanil was provided for analgesia. In all patients we monitored hemodynamic and respiratory patterns, gases, temperature, and hypnosis (BIS, ES and ER) as well as cerebral blood flow estimated by pulsed Doppler ultrasound in the middle cerebral artery. The resistance index, pulsatility index, mean velocity, and estimated baseline cerebral blood flow were calculated from the Doppler sonogram. Correlations (Pearson's r) were calculated between BIS, ES, ER, the pulsatility index, resistance index, mean flow velocity, estimated cerebral blood flow, fraction of end-tidal carbon dioxide, and temperature. A regression model was constructed. Induction caused a pattern of high velocity (elevated mean velocity and normal or reduced pulsatility index) until the lowest BIS and ES values of 31 and 29, respectively, were reached. During maintenance, the Doppler sonogram pattern was slower (normalization of the pulsatility index, the resistance index, and mean velocity). Changes in flow and absolute entropy and BIS values were statistically correlated (Pearson's r values > or = 0.91); there was 95.6% agreement between Doppler values and BIS and agreement between BIS and ES values of 35 to 45. On awakening, flow velocities approached baseline values when BIS and ES rose to between 90 and 98. The estimated cerebral blood flow underwent fluctuations coinciding with an approximately concomitant increase or decrease in BIS (r > 0.95); the BIS response occurred with a slight delay of no more than a minute. The entropy measurements did not reflect the fluctuations. We show Doppler ultrasound patterns during anesthetic induction with sevoflurane. Systems for monitoring hypnosis could be considered indirect measurements of cerebral blood flow; BIS measurements are more sensitive to change. Transcranial Doppler ultrasound facilitates the observation of changes in blood flow that occur at different levels of hypnosis during anesthesia.

Doppler transcraneal, BIS y entropía como medición indirecta del flujo cerebral durante la anestesia total intravenosa en pacientes pediátricos

Transcranial Doppler ultrasound is a noninvasive technique for monitoring the velocity of blood flow in the main intracranial arteries, particularly those in the circle of Willis. Our aim was to assess whether changes in cerebral arterial blood flow in anesthetized pediatric patients detected by pulsed Doppler ultrasound correlate with changes in the bispectral (BIS) index and electroencephalographic state and response entropy (ES and ER, respectively). Prospective, blinded observational study of 36 pediatric patients (age range, 5 to 11 years) under total intravenous anesthesia for minor surgical procedures. Propofol and fentanyl were used for induction; propofol and remifentanil in continuous perfusion and a single dose of cisatracurium were used for maintenance. In all patients we monitored hemodynamic and respiratory patterns, gases, temperature, and hypnosis (BIS, ES and ER) as well as cerebral blood flow estimated by pulsed Doppler ultrasound in the middle cerebral artery. Raw data were subjected to statistical smoothing. The resistance index, pulsatility index, mean velocity, and estimated baseline cerebral blood flow were calculated from the Doppler sonogram. We then studied the correlations between the Doppler-derived values and BIS, ES, ER, fraction of end-tidal carbon dioxide, and temperature. The variables were entered into logistic regression. The pattern at induction indicated high resistance (low mean velocities and high pulsatility indexes) until the lowest BIS and ES values of 31 and 29, respectively, were reached. During maintenance, the Doppler sonogram pattern was slower (normalization of the pulsatility index, the resistance index, and mean velocity). Changes in flow and absolute entropy and BIS values were statistically correlated (Pearson's r values > or = 0.91); there was 95.6% agreement between Doppler values and BIS and agreement between BIS and ES values of 35-45. On awakening, flow velocities approached baseline values when BIS and ES rose to between 90 and 98. The estimated cerebral blood flow underwent fluctuations coinciding with an approximately concomitant increase or decrease in BIS (r > 0.95); the response of BIS was slightly delayed by no more than a minute but there was no corresponding response of entropy measurements. We report Doppler ultrasound patterns during anesthesia with propofol. Systems for monitoring hypnosis could be considered indirect measurements of cerebral blood flow; BIS measurements are more sensitive to flow change. Transcranial Doppler ultrasound facilitates the observation of changes in blood flow that occur at different levels of hypnosis during anesthesia.

Repeated episodes of difficulty with arousal following general anesthesia in a patient with ulnar neuropathy

Delayed emergence following general anesthesia may be due to serious life-threatening disorders and deserves prompt evaluation. Rarely, delayed emergence has been attributed to a psychiatric or psychological cause. This report describes an otherwise healthy and mentally sound 52-year-old woman who experienced repeated dissociative episodes following general anesthesia for minor surgical procedures. These episodes lasted for 5 h and resulted in admission to the intensive care unit. The current literature is reviewed to identify commonalities among previously reported cases and to discuss different psychiatric and psychological mechanisms that can play a role in the development of this disorder.

Tryptophan metabolism via serotonin in human CSF of different brain sites using a new neuroendoscopic technique

Abstract A new neuroendoscopic technique has permitted a precise and accurate exploration of all the cerebral ventricles, making possible the study of the CSF of the lateral ventricles and, above all, the CSF adjacent to the walls of the third ventricle in humans. The concentrations of tryptophan and its metabolites via serotonin were measured in the CSF of different sites of the cerebral cavity, in particular in the third ventricle. Patients affected with non-communicating hydrocephalus undergoing neuroendoscopic third ventriculostomy were enrolled in the study. As controls, subjects not suffering from any neurological disease, who underwent lumbar subarachnoid anaesthesia for minor surgical procedures, provided lumbar CSF, and patients affected by Chiari malformation provided cisternal and right ventricular CSF. Tryptophan concentration was higher in right ventricular CSF than in lumbar CSF. Serotonin (5-HT) was detectable in the CSF of the right ventricle of hydrocephalic individuals. 5-Hydroxyindoleacetic acid (5-HIAA) was higher in the right ventricular CSF than in the cisternal and lumbar CSF both in controls and hydrocephalic subjects. However, the 5-HIAA level was higher in the right ventricular and cisternal CSF in hydrocephalic individuals in comparison to controls. 5-HT presented the highest concentration in the pineal recess, whereas the highest amounts of 5-HIAA were found in the choroids plexus, third and right ventricles and the lowest in the pineal recess, subarachnoid space and intepeduncular cistern. Melatonin is more concentrated within the ventricles, in particular the third ventricle, and in the CSF pineal recess. The use of this neuroendoscopic technique in hydrocephalic patients provides new insight into the metabolic pathway of tryptophan via serotonin in the CSF.

Aerophagia and anesthesia: an unusual cause of ventilatory insufficiency in a neonate

We describe a healthy neonate with abdominal distention, inadequate ventilation, and delayed extubation during anesthesia for minor surgery. Following rectal decompression and successful extubation, extreme abdominal distention recurred postoperatively after ingestion of clear fluids. We elicited a history of frequent and excessive flatus from the parents, and abdominal radiography revealed distended loops of small bowel with small lung volumes suggestive of aerophagia. The differential diagnosis of aerophagia is reviewed, the anesthetic implications discussed, and relevant literature pertaining to this condition summarized.

Intravenous regional anaesthesia

Intravenous regional anaesthesia (IVRA) was first described by August Bier in 1908. He observed that when local anaesthetic was injected intravenously between two tourniquets on a limb, a rapid onset of anaesthesia occurred in the area between the tourniquets and a slower onset occurred beyond the distal tourniquet. The technique did not become popular until the 1960s when it was reintroduced by Holmes. Today, the technique is slightly modified, using either a single or a double tourniquet at one site and injecting local anaesthetic as distal as possible to the cuff. The double tourniquet is used to increase safety and to reduce tourniquet pain in the awake patient, but there is potential for confusion and accidental deflation of the wrong cuff, which may lead to toxic systemic levels of local anaesthetic. IVRA is technically straightforward and does not require specific anatomical knowledge. Published series report successful anaesthesia in 96-100% of patients with a low incidence of side-effects. It is a reliable, simple and safe method of providing anaesthesia for minor surgical procedures to the extremities if it is administered by experienced clinicians. The advantages and disadvantages of IVRA are listed in Figure 1.