Use of stepwise lung recruitment maneuver to predict fluid responsiveness under lung protective ventilation in the operating room.

Recent research has revealed that hemodynamic changes caused by lung recruitment maneuvers (LRM) with continuous positive airway pressure can be used to identify fluid responders. We investigated the usefulness of stepwise LRM with increasing positive end-expiratory pressure and constant driving pressure for predicting fluid responsiveness in patients under lung protective ventilation (LPV). Forty-one patients under LPV were enrolled when PPV values were in a priori considered gray zone (4% to 17%). The FloTrac-Vigileo device measured stroke volume variation (SVV) and stroke volume (SV), while the patient monitor measured pulse pressure variation (PPV) before and at the end of stepwise LRM and before and 5 min after fluid challenge (6 ml/kg). Fluid responsiveness was defined as a ≥ 15% increase in the SV or SV index. Seventeen were fluid responders. The areas under the curve for the augmented values of PPV and SVV, as well as the decrease in SV by stepwise LRM to identify fluid responders, were 0.76 (95% confidence interval, 0.61-0.88), 0.78 (0.62-0.89), and 0.69 (0.53-0.82), respectively. The optimal cut-offs for the augmented values of PPV and SVV were > 18% and > 13%, respectively. Stepwise LRM -generated augmented PPV and SVV predicted fluid responsiveness under LPV.

Effects of head-elevated position on tracheal intubation using a McGrath MAC videolaryngoscope in patients with a simulated difficult airway: a prospective randomized crossover study.

BACKGROUND: The head-elevated laryngoscopy position has been described to be optimal for intubation, particularly in obese patients and those with anticipated difficult airways. Horizontal alignment of the external auditory meatus and sternal notch (AM-S) can be used as endpoints for optimal positioning. Thus, we aligned the head-elevated position with the AM-S in the horizontal plane and evaluated its effect on laryngeal visualization and ease of intubation using a McGrath MAC videolaryngoscope in patients with a simulated difficult airway. METHODS: Sixty-four patients were included in this prospective, crossover, randomized controlled trial. A cervical collar was used to restrict neck movement and mouth opening. The head-elevated position was achieved by raising the back section of the operation room table and ensuring that the end point was horizontally aligned with the AM-S (table-ramp method). The laryngeal view was randomly assessed in both head-flat and head-elevated positions based on the percentage of glottic opening (POGO) score and modified Cormack-Lehane (MCL) grade. External laryngeal manipulation was not permitted when laryngeal visualization was scored. The trachea was intubated only once (in the second position). The ease of intubation was assessed based on the need for optimization maneuvers, intubation difficulty scale (IDS) scores and time to intubation. RESULTS: The mean table-ramp angle required to achieve the horizontal alignment of AM-S was 17.5 ± 4.1°. The mean POGO score improved significantly in the head-elevated position (59.4 ± 23.8%) when compared with the head-flat position (37.5 ± 24%) (P <  0.0001). MCL grade 1 or 2a was achieved in 56 (85.9%) and 28 (43.7%) of patients in the head-elevated and head-flat positions, respectively (P <  0.0001). Optimization maneuvers for intubation were required in 7 (21.9%) and 17 (53.1%) patients in the head-elevated and head-flat positions, respectively (P <  0.0001). The IDS scores and time to intubation did not differ significantly between the two positions. CONCLUSION: In the head-elevated position, aligning the AM-S in the horizontal plane consistently improved laryngeal visualization without worsening the view when the McGrath MAC videolaryngoscope was used in patients with simulated difficult airways. It also improved the ease of intubation, which reduced the need for optimization maneuvers. TRIAL REGISTRATION: This trial was registered with www. CLINICALTRIALS: gov , NCT04716218 , on 20/01/2021.

Postoperative outcomes of purely laparoscopic donor hepatectomy compared to open living donor hepatectomy: a preliminary observational study.

PURPOSE: To lessen the physical, cosmetic, and psychological burden of donors, purely laparoscopic donor hepatectomy (PLDH) has been proposed as an ideal method for living donors. Our study aimed to prospectively compare the effect of PLDH and 2 other types of open living donor hepatectomy (OLDH) on postoperative pain and recovery. METHODS: Sixty donors scheduled to undergo donor hepatectomy between March 2015 and November 2017 were included. Donors were divided into 3 groups by surgical technique: OLDH with a subcostal incision (n = 20), group S; OLDH with an upper midline incision (n = 20), group M; and PLDH (n = 20), group L. The primary outcomes were postoperative pain and analgesic requirement during postoperative day (POD) 3. Other variables regarding postoperative recovery were also analyzed. RESULTS: Although pain relief during POD 3, assessed by visual analog scale (VAS) score and analgesic requirement, was similar among the 3 groups, group L showed lower VAS scores and opioid requirements than group M. Moreover, group L was associated with a rapid postoperative recovery evidenced by the shorter hospital length of stay and more frequent return to normal activity on POD 30. CONCLUSION: This pilot study failed to verify the hypothesis that PLDH reduces postoperative pain. PLDH did not reduce postoperative pain but showed faster recovery than OLDH.

Efficacy of intermittent epidural dexamethasone bolus for zoster-associated pain beyond the acute phase.

Herpes zoster develops when latent varicella zoster virus is reactivated in the trigeminal or dorsal root ganglions. Zoster-associated pain (ZAP) is neuropathic pain caused by the herpes zoster virus. Histological studies of postherpetic neuralgia patients suggest that inflammation is involved in ZAP. The effectiveness of local anesthetic and steroid epidural injections in ZAP patients has been reported. However, most studies included patients with acute herpes zoster, and the safety and therapeutic effects of different doses of epidural steroids in ZAP patients remain elusive. In this study, we randomly assigned 42 patients with severe ZAP beyond the acute phase, as determined by a numeric rating scale (NRS) score ≥7, to receive continuous epidural infusion of local anesthetics with either a one-time 5-mg dose or intermittent repeated doses (15 mg total) of dexamethasone. We found that intermittent repeated epidural dexamethasone bolus resulted in reduced NRS scores and an increased likelihood of complete remission in ZAP patients without any adverse effects. Thus, our results suggest that intermittent repeated epidural dexamethasone administration is safe and effective for treatment of ZAP beyond the acute phase.

Comparison of C-MAC D-blade videolaryngoscope and McCoy laryngoscope efficacy for nasotracheal intubation in simulated cervical spinal injury: a prospective randomized comparative study.

BACKGROUND: Immobilization with cervical spine worsens endotracheal intubation condition. Though various intubation devices have been demonstrated to perform well in oral endotracheal intubation, limited information is available concerning nasotracheal intubation (NTI) in patients with cervical spine immobilization. The present study compared the performance of the C-MAC D-Blade videolaryngoscope with the McCoy laryngoscope for NTI in patients with simulated cervical spine injuries. METHODS: This was a prospective, randomized, controlled, study done in a tertiary hospital. Ninety-five patients requiring NTI were included in data analysis: McCoy group (group M, n = 47) or C-MAC D-Blade videolaryngoscope group (group C, n = 48). A Philadelphia neck collar was applied before anesthetic induction to immobilize the cervical spine. Single experienced anesthesiologist performed NTI. The primary outcome was duration of intubation divided by three steps: nose to oropharynx; oropharynx into glottic inlet; and glottic inlet to trachea. Secondary outcomes included glottic view as percentage of glottis opening (POGO) score and Cormack-Lehance (CL) grade, modified nasal intubation-difficulty scale (NIDS) rating, hemodynamic changes before and after intubation, and complications. RESULTS: Total intubation duration was significantly shorter in group C (39.5 ± 11.4 s) compared to group M (48.1 ± 13.9 s). Group C required significantly less time for glottic visualization and endotracheal tube placement in the trachea. More patients in group C had CL grade I and higher POGO scores (P <  0.001, for both measures). No difficulty in NTI (modified NIDS = 0) was more in group C than group M. Hemodynamic changes and incidence of complications were comparable between groups. CONCLUSION: The C-MAC D-Blade videolaryngoscope is an effective tool for NTI in a simulated difficult airway, which improves glottic visualization and shortens intubation time relative to those with McCoy laryngoscope. TRIAL REGISTRATION: Clinical Research Information Service of the Korea National Institute of Health, Identification number: KCT 0004535, Registered December 10, 2019, Retrospectively registered, http://cris.nih.go.kr.

Correction to: Mitral regurgitation detected during the intraoperative period after atrial septal defect closure: a case report.

The original article [1] contained a typo in author, Joo Hyun Jun's name. This has now been corrected.

The tidal volume challenge improves the reliability of dynamic preload indices during robot-assisted laparoscopic surgery in the Trendelenburg position with lung-protective ventilation.

BACKGROUND: The reliability of pulse pressure variation (PPV) and stroke volume variation (SVV) is controversial under pneumoperitoneum. In addition, the usefulness of these indices is being called into question with the increasing adoption of lung-protective ventilation using low tidal volume (VT) in surgical patients. A recent study indicated that changes in PPV or SVV obtained by transiently increasing VT (VT challenge) accurately predicted fluid responsiveness even in critically ill patients receiving low VT. We evaluated whether the changes in PPV and SVV induced by a VT challenge predicted fluid responsiveness during pneumoperitoneum. METHODS: We performed an interventional prospective study in patients undergoing robot-assisted laparoscopic surgery in the Trendelenburg position under lung-protective ventilation. PPV, SVV, and the stroke volume index (SVI) were measured at a VT of 6 mL/kg and 3 min after increasing the VT to 8 mL/kg. The VT was reduced to 6 mL/kg, and measurements were performed before and 5 min after volume expansion (infusing 6% hydroxyethyl starch 6 ml/kg over 10 min). Fluid responsiveness was defined as ≥15% increase in the SVI. RESULTS: Twenty-four of the 38 patients enrolled in the study were responders. In the receiver operating characteristic curve analysis, an increase in PPV > 1% after the VT challenge showed excellent predictive capability for fluid responsiveness, with an area under the curve (AUC) of 0.95 [95% confidence interval (CI), 0.83-0.99, P < 0.0001; sensitivity 92%, specificity 86%]. An increase in SVV > 2% after the VT challenge predicted fluid responsiveness, but showed only fair predictive capability, with an AUC of 0.76 (95% CI, 0.60-0.89, P < 0.0006; sensitivity 46%, specificity 100%). The augmented values of PPV and SVV following VT challenge also showed the improved predictability of fluid responsiveness compared to PPV and SVV values (as measured by VT) of 6 ml/kg. CONCLUSIONS: The change in PPV following the VT challenge has excellent reliability in predicting fluid responsiveness in our surgical population. The change in SVV and augmented values of PPV and SVV following this test are also reliable. TRIAL REGISTRATION: This trial was registered with Clinicaltrials.gov, NCT03467711 , 10th March 2018.

Is Tube Thermosoftening Helpful for Videolaryngoscope-Guided Nasotracheal Intubation?: A Randomized Controlled Trial.

BACKGROUND: Thermosoftening of the endotracheal tube (ETT) and telescoping the ETT into a rubber catheter have been suggested as a method for reducing epistaxis during nasotracheal intubation (NTI). However, thermosoftening technique is known to make it difficult to navigate the ETT into trachea without the use of Magill forceps during NTI. The cuff inflation technique has been suggested as an effective alternative to the use of Magill forceps to improve the oropharyngeal navigation of the ETT, irrespective of their stiffness, during direct laryngoscope-guided NTI. We evaluated whether thermosoftening of the ETT telescoped into rubber catheters has an additional benefit in reducing nasal injury. Simultaneously, we also evaluated whether thermosoftening of the ETT worsened orotracheal navigability during cuff inflation-supplemented videolaryngoscope-guided NTI. METHODS: One hundred forty patients were randomly assigned to 1 of the 2 groups depending on whether the ETT was softened by warming or not. The primary outcome was the incidence of epistaxis during NTI. The secondary outcome was nasotracheal navigability of the ETT, assessed by navigation grade and time required for insertion of ETT in each phase (from nose to oropharynx, from oropharynx to glottic inlet aided by cuff inflation if needed, and from glottic inlet to trachea). RESULTS: The ETTs were successfully inserted through the selected nostril of all 140 patients. In the thermosoftening group, the incidence and severity of epistaxis was significantly lower (7% vs 51%; difference of 44.2%; 95% confidence interval, 29.9%-56.2%; P < .001), and the ETT passed through the nasal cavity with lower resistance (P = .001) and less time (P < .001) when compared to the control group. No difference was found in the ease of ETT insertion (navigation grade and time required) from the oropharynx to the glottic inlet (P > .99 and P = .054, respectively) and from the glottic inlet to the trachea (P > .99 and P = .750, respectively) between the 2 groups. In both groups, all ETTs could be navigated into the trachea without the use of Magill forceps. CONCLUSIONS: Supplemented with cuff inflation during videolaryngoscope-guided NTI, thermosoftening of the ETT telescoped into rubber catheters has a substantial benefit because it significantly reduces the incidence of epistaxis without worsening the oropharyngeal navigability of the ETT.

Mitral regurgitation detected during the intraoperative period after atrial septal defect closure: a case report.

BACKGROUND: Atrial septal defect (ASD) is a congenital cardiac defect often diagnosed in adult patients. Mitral regurgitation (MR) observed in ASD patients mostly improves after ASD closure. However, a subset of adult ASD patients present new-onset MR or aggravation of preexisting MR after ASD closure. Intraoperative MR aggravation after surgical ASD closure is a rare occurrence which has not been reported in the literature to date. CASE PRESENTATION: A 54-year-old woman was referred to our center due to large secundum ASD with a diameter of 17 mm which was incidentally detected on pre-operative echocardiography at a local clinic. Surgical repair of ASD under mini-thoracotomy was performed. After completion of the operation, intra-operative transesophageal echocardiography showed newly developed Grade II MR which subsequently deteriorated to severe level on postoperative day 3. Because the patient was asymptomatic, we decided to observe closely and treat conservatively with diuretics. Thereafter, echocardiography was evaluated on postoperative day 10 and MR disappeared to trivial level. CONCLUSIONS: Intraoperative MR aggravation is a rare complication following ASD closure. The possibility of MR aggravation should be evaluated in all ASD patients prior to surgery. This case highlights the importance of mitral leaflet examination after ASD closure for early detection of MR.

Efficacy of forced-air warming and warmed intravenous fluid for prevention of hypothermia and shivering during caesarean delivery under spinal anaesthesia: A randomised controlled trial.

BACKGROUND: Peri-operative hypothermia and shivering are frequent events in patients during caesarean delivery under spinal anaesthesia. OBJECTIVE: We assessed the efficacy of combined pre-anaesthetic forced-air warming in combination with warmed intravenous fluid infusion for preventing hypothermia and shivering during caesarean delivery under spinal anaesthesia. DESIGN: A randomised controlled study. SETTING: A tertiary care teaching hospital from July 2017 to April 2018. PATIENTS: A total of 50 pregnant women, American Society of Anaesthesiologists physical status 2, aged 20 to 45 years, scheduled for caesarean delivery under spinal anaesthesia. INTERVENTION: Patients were enrolled and randomised into two groups: an active warming group (n = 25), which received combined pre-anaesthetic whole body forced-air warming for 15 min and prewarmed intravenous fluids, and a control group, which received no active warming or warmed fluids (C group; n = 25). Spinal anaesthesia was induced with 10 mg bupivacaine containing fentanyl (10 µg). MAIN OUTCOME MEASURES: Tympanic membrane temperature and shivering severity were measured at baseline and every 10 min during surgery, and then every 10 min for 1 h postoperatively. Neonatal outcomes (tympanic membrane temperature at birth, umbilical venous blood pH, Apgar score) were also recorded. RESULTS: The incidences of peri-operative hypothermia (0 vs. 48%, P < 0.001) and shivering (22 vs. 52%, P = 0.031) were significantly lower in the active warming than in the C group. The maximum temperature change was also significantly lower in the active warming than in the C group. Maternal thermal comfort scores were higher in the active warming than in the C group. Neonatal parameters were not significantly different between the groups. CONCLUSION: The combination of pre-anaesthetic forced-air warming and warmed intravenous fluid infusions appears to be effective for preventing hypothermia and shivering during caesarean delivery under spinal anaesthesia. TRIAL REGISTRATION: This trial was registered with Clinical Trials.gov (identifier: NCT03256786).

Effect of pre-warming on perioperative hypothermia during holmium laser enucleation of the prostate under spinal anesthesia: a prospective randomized controlled trial.

BACKGROUND: The purpose of this study is to assess whether the application of preoperative forced air warming set to high temperature (> 43 °C) for brief period can increase temperature on admission to the postanesthesia care unit (PACU) and prevent hypothermia or shivering during holmium laser enucleation of the prostate performed under spinal anesthesia. METHODS: Fifty patients were enrolled were assigned randomly to receive passive insulation (control group, n = 25) or forced-air skin surface warming for 20 min before spinal anesthesia (pre-warming group, n = 25). The primary outcome was temperature at PACU admission. RESULTS: The pre-warming group had a significantly higher temperature on admission to the PACU than the control group (35.9 °C [0.1] vs 35.6 °C [0.1], P = 0.023; 95% confidence interval of mean difference, 0.1 °C-0.5 °C). The trend of decreasing core temperature intraoperatively was not different between groups (P = 0.237), but intraoperative core temperature remained approximately 0.2 °C higher in the pre-warming group (P = 0.005). The incidence of hypothermia on admission to the PACU was significantly lower in the pre-warming group (56% vs 88%, P = 0.025). Shivering occurred in 14 patients in the control group, and 4 patients in the pre-warming group (P = 0.007). CONCLUSION: Brief pre-warming at 45 °C increased perioperative temperature and decreased the incidence of hypothermia and shivering. However, it was not sufficient to modify the decline of intraoperative core temperature or completely prevent hypothermia and shivering. Continuing pre-warming to immediately before induction of spinal anesthesia or combining pre-warming with intraoperative active warming may be necessary to produce clearer thermal benefits in this surgical population. TRIAL REGISTRATION: This trial was registered with Clinicaltrials.gov, NCT03184506 , 5th June 2017.

Longer storage of red blood cells does not affect mortality in transfused liver transplant recipients.

BACKGROUND: The characteristics of red blood cell (RBC) products change after 2 weeks of cold storage. It is unclear whether older RBCs affect mortality after liver transplantation. This retrospective cohort study aimed to evaluate the association between the age of transfused RBCs and death after living donor liver transplantation (LDLT). STUDY DESIGN AND METHODS: Of 200 recipients who underwent LDLT, 118 who received RBCs with a mean storage duration of less than 10 days (shorter storage group) were compared with 82 with an RBC mean storage duration of more than 14 days (longer storage group). Key exclusion criteria were transfusion of very fresh RBCs stored for less than 4 days and transfusion of old RBCs in recipients of the shorter storage group. The primary outcome was posttransplant overall death. Survival analysis was performed using the Cox model. RESULTS: Mean RBC storage duration was 7 days in the shorter storage group and 17 days in the longer storage group. Death probability at 1, 2, and 5 years posttransplant was 5.1%, 7.6%, and 13.6% in the shorter storage group, respectively, and 6.1%, 8.5%, and 13.5% in the longer storage group. Death risk was comparable between the two groups in univariable (hazard ratio [HR] 1.00, 95% confidence interval [CI], 0.47-2.16, p = 0.991) and multivariable (HR 1.07, 95% CI, 0.46-2.50, p = 0.882) analyses. Graft failure risk was also comparable (HR 1.04, 95% CI, 0.50-2.18, p = 0.916). Hepatocellular carcinoma recurrence probability at 1, 2, and 5 years was 10.8%, 15.4%, and 23.1%, respectively, in the shorter storage group and 11.4%, 15.9%, and 20.7% in the longer storage group (HR 0.84, 95% CI, 0.37-1.89, p = 0.670). No significant differences were observed regarding graft regeneration/function, vascular/biliary complications, acute kidney injury, surgical site infection, or rejection (p > 0.05). CONCLUSIONS: No evidence was found that transfusion of old RBCs contributes to death after LDLT.

Comparison of intrathecal morphine and surgical-site infusion of ropivacaine as adjuncts to intravenous patient-controlled analgesia in living-donor kidney transplant recipients.

INTRODUCTION: This prospective observational study compared the postoperative analgesic effectiveness of intrathecal morphine (ITM) and surgical-site infusion (SSI) of ropivacaine as adjuncts to intravenous (IV) patient-controlled analgesia (PCA) (fentanyl) in living-donor kidney transplant recipients. METHODS: Patients undergoing living-donor kidney transplantation who received ITM or SSI in addition to IV PCA were included. Rescue analgesia was achieved with IV meperidine as required. The primary outcome, measured using the Numeric Pain Rating Scale (NRS), was pain at rest and when coughing. Patients were assessed for 48 hours after surgery. RESULTS: A total of 53 patients (32 ITM, 21 SSI) were included in the study. The ITM group showed significantly lower NRS scores, at rest and when coughing, for up to 12 and eight hours. NRS scores were comparable between the groups at other times. The ITM group had significantly less postoperative systemic opioid requirement in the first 24 hours, but there was no significant difference between the systemic opioid consumption of the groups on postoperative Day 2. In the ITM group, 3 (9.4%) patients presented with bradypnoea and 1 (3.1%) with excessive sedation in the first 12 postoperative hours. More patients in the ITM group developed pruritus requiring treatment during the first 24 hours. There were no differences between the groups in other outcomes (e.g. nausea/vomiting, change in pulmonary or kidney functions). CONCLUSION: Compared with SSI, ITM reduced immediate postoperative pain and IV opioid consumption on postoperative Day 1 after living-donor kidney transplantation, but at the cost of increased pruritus and respiratory depression.

Randomized trial of subfascial infusion of ropivacaine for early recovery in laparoscopic colorectal cancer surgery.

BACKGROUND: There is a need for investigating the analgesic method as part of early recovery after surgery tailored for laparoscopic colorectal cancer (LCRC) surgery. In this randomized trial, we aimed to investigate the analgesic efficacy of an inverse 'v' shaped bilateral, subfascial ropivacaine continuous infusion in LCRC surgery. METHODS: Forty two patients undergoing elective LCRC surgery were randomly allocated to one of two groups to receive either 0.5% ropivacaine continuous infusion at the subfascial plane (n = 20, R group) or fentanyl intravenous patient controlled analgesia (IV PCA) (n = 22, F group) for postoperative 72 hours. The primary endpoint was the visual analogue scores (VAS) when coughing at postoperative 24 hours. Secondary end points were the VAS at 1, 6, 48, and 72 hours, time to first flatus, time to first rescue meperidine requirement, rescue meperidine consumption, length of hospital stay, postoperative nausea and vomiting, sedation, hypotension, dizziness, headache, and wound complications. RESULTS: The VAS at rest and when coughing were similar between the groups throughout the study. The time to first gas passage and time to first rescue meperidine at ward were significantly shorter in the R group compared to the F group (P = 0.010). Rescue meperidine was administered less in the R group; however, without statistical significance. Other study parameters were not different between the groups. CONCLUSIONS: Ropivacaine continuous infusion with an inverse 'v ' shaped bilateral, subfascial catheter placement showed significantly enhanced bowel recovery and analgesic efficacy was not different from IV PCA in LCRC surgery.

Is Preoperative Biochemical Testing for Pheochromocytoma Necessary for All Adrenal Incidentalomas?

This study examined whether imaging phenotypes obtained from computed tomography (CT) can replace biochemical tests to exclude pheochromocytoma among adrenal incidentalomas (AIs) in the preoperative setting.We retrospectively reviewed the medical records of all patients (n = 251) who were admitted for operations and underwent adrenal-protocol CT for an incidentally discovered adrenal mass from January 2011 to December 2012. Various imaging phenotypes were assessed for their screening power for pheochromocytoma. Final diagnosis was confirmed by biopsy, biochemical tests, and follow-up CT.Pheochromocytomas showed similar imaging phenotypes as malignancies, but were significantly different from adenomas. Unenhanced attenuation values ≤10 Hounsfield units (HU) showed the highest specificity (97%) for excluding pheochromocytoma as a single phenotype. A combination of size ≤3 cm, unenhanced attenuation values ≤ 10 HU, and absence of suspicious morphology showed 100% specificity for excluding pheochromocytoma.Routine noncontrast CT can be used as a screening tool for pheochromocytoma by combining 3 imaging phenotypes: size ≤3 cm, unenhanced attenuation values ≤10 HU, and absence of suspicious morphology, and may substitute for biochemical testing in the preoperative setting.

Comparison of the ease of laryngeal mask airway ProSeal insertion and the fiberoptic scoring according to the head position and the presence of a difficult airway.

BACKGROUND: The sniffing position is recommended for conventional laryngeal mask airway (LMA) insertion. However, there has been a high success rate of LMA insertion with the head in the neutral position. The effect of a difficult airway on the ease of LMA insertion is not clear. In this study, we compared the ease of LMA ProSeal™ (PLMA) insertion and the fiberoptic scoring according to the head position and the presence of a difficult airway. METHODS: After obtaining informed consent from the subjects, we enrolled 144 adult patients (age range: 18-65) with an ASA physical status 1 or 2. After evaluation of the airway, all the patients were grouped into the EA (easy airway) group (n = 68) and the DA (difficult airway) group (n = 76). According to the head position, each group was divided into the EA-SE (extension) group (n = 35), the EA-SN (sniffing) group (n = 33), the DA-SE group (n = 39) and the DA-SN group (n = 37). The success rate and insertion time at the first attempt were evaluated. The position of the PLMA was fiberoptically scored from the mask aperture of the airway tube in the original head position. After the head position was changed to the sniffing and neutral positions in the SE and SN group, respectively, the position of PLMA was re-evaluated fiberoptically. RESULTS: The success rate and insertion time at the first attempt and the fiberoptic score showed no significant difference among the groups. After head position was changed, there were no significant changes in the fiberopitc scores. CONCLUSIONS: A difficult airway and the head position had no influence on the ease of PLMA insertion and the fiberopic score. Therefore, the head position can be selected according to the individual patient's situation.

The effect of different oxygen administration under combined spinal-epidural anesthesia for cesarean section.

BACKGROUND: During cesarean section under regional anesthesia, it is current practice to provide the parturient with a source of supplemental oxygen. We compared the effect of high flow oxygen by mask with that of low flow oxygen by nasal prongs. METHODS: Fifty eight parturients presenting for elective cesarean section under combined spinal-epidural anesthesia were randomly assigned to one of the three groups to be given either oxygen 4 L/min by mask, oxygen 8 L/min by mask or oxygen 2 L/min by nasal prongs. Umbilical arterial and venous blood samples were taken and analysed immediately after delivery. RESULTS: There were no significant differences in the umbilical arterial or venous pH, partial pressure of oxygen and partial pressure of carbon dioxide among the three groups. In neonatal outcome, there were no differences in Apgar scores. CONCLUSIONS: It Makes No Differences Whether The Parturients Received Supplemental Oxygen By Nasal Prongs Or Simple Face Mask During Cesarean Section Under Combined Spinal-epidural Anesthesia.