The Effect of Prolonged Face Mask Ventilation on Gastric Insufflation: A Prospective Observational Study.

BACKGROUND: Pulmonary aspiration is a potentially lethal perioperative complication that can be precipitated by gastric insufflation. Face mask ventilation (FMV), a ubiquitous anesthetic procedure, can cause gastric insufflation. FMV with an inspiratory pressure of 15 cm H2O provides the best balance between adequate pulmonary ventilation and a low probability of gastric insufflation. There is no data about the effects of FMV > 120 seconds. OBJECTIVES: To investigate the effect of prolonged FMV on gastric insufflation. METHODS: We conducted a prospective observational study at a tertiary medical center with female patients who underwent oocyte retrieval surgery under general anesthesia FMV. Pre- and postoperative gastric ultrasound examinations measured the gastric antral cross-sectional area to detect gastric insufflation. Pressure-controlled FMV with an inspiratory pressure of 15 cm H2O was continued from the anesthesia induction until the end of the surgery. RESULTS: The study comprised 49 patients. Baseline preoperative gastric ultrasound demonstrated optimal and good image quality. All supine measurements were feasible. The median duration of FMV was 13 minutes (interquartile range 9-18). In the postoperative period, gastric insufflation was detected in only 2 of 49 patients (4.1%). There was no association between the duration of FMV and delta gastric antral cross-sectional area (ß -0.01; 95% confidence interval -0.04 to 0.01, P = 0.31). CONCLUSIONS: Pressure-controlled FMV with an inspiratory pressure of 15 cm H2O carries a low incidence of gastric insufflations, not only as a bridge to a definitive airway but as an alternative ventilation method for relatively short procedures in selective populations.

Prophylactic Administration of Tranexamic Acid Reduces Blood Products' Transfusion and Intensive Care Admission in Women Undergoing High-Risk Cesarean Sections.

Postpartum hemorrhage (PPH) remains a major cause of maternal mortality. Tranexamic acid (TxA) has shown effectiveness in reducing PPH-related maternal bleeding events and deaths. We conducted a cohort study including parturient women at high risk of bleeding after undergoing a cesarean section (CS). Participants were divided into two groups: the treatment group received prophylactic 1-g TxA before surgery (n = 500), while the comparison group underwent CS without TxA treatment (n = 500). The primary outcome measured increased maternal blood loss following CS, defined as more than a 10% drop in hemoglobin concentration within 24 h post-CS and/or a drop of ≥2 g/dL in maternal hemoglobin concentration. Secondary outcomes included PPH indicators, ICU admission, hospital stay, TxA complications, and neonatal data. TxA administration significantly reduced hemoglobin decrease by more than 10%: there was a 35.4% decrease in the TxA group vs. a 59.4% decrease in the non-TxA group, p < 0.0001 and hemoglobin decreased by ≥2 g/dL (11.4% in the TxA group vs. 25.2% in non-TxA group, p < 0.0001), reduced packed red blood cell transfusion (p = 0.0174), and resulted in lower ICU admission rates (p = 0.034) and shorter hospitalization (p < 0.0001). Complication rates and neonatal outcomes did not differ significantly. In conclusion, prophylactic TxA administration during high-risk CS may effectively reduce blood loss, providing a potential intervention to improve maternal outcomes.

Incidence of conversion to general anaesthesia and need for intravenous supplementation in parturients undergoing caesarean section under spinal anaesthesia: A retrospective observational study.

BACKGROUND: Conversion from spinal anaesthesia to general anaesthesia (GA) was shown to be associated with more complications. It has been postulated that spinal injection of a low dose of local anaesthetic is a risk factor. We aimed to discover the rate of conversion from spinal anaesthesia to GA in women who received at least 10 mg heavy bupivacaine and opioids and assess its risk factors. METHODS: All women that underwent spinal anaesthesia for caesarean section from 1 January 2017 to 31 December 2020 were included in this analysis. Spinal anaesthesia was performed according to department protocol using heavy bupivacaine 0.5% 10-13 mg, fentanyl 20 µg, and morphine 0.1 mg. We examined rate of conversion from spinal anaesthesia to GA and rate of need for analgesia/sedation. RESULTS: There were 1.7% of women that required conversion to GA. Bupivacaine dose (OR 0.54 [95% CI 0.38 to 0.75], p < 0.001), surgery time (OR 1.03 [95% CI 1.02 to 1.04], p < 0.001), emergency caesarean section (OR 1.06 [95% CI 1.16 to 3.76], p = 0.015), and postpartum haemorrhage (OR 5.96 [95% CI 1.09 to 25.18], p = 0.025) were independent predictors of need for conversion to GA. Of the women who had CS under spinal anaesthesia, 4.1% of parturients required intraoperative analgesics/sedatives and 9.1% required anxiolysis. CONCLUSIONS: A small proportion of women required conversion to GA. This conversion occurred especially with emergency caesarean section and when low spinal bupivacaine doses were used.

Risk for molecular contamination of tissue samples evaluated for targeted anti-cancer therapy.

With the increasing usage of sensitive PCR technology for pharmacogenetics, cross contamination becomes a significant concern. Researchers employed techniques which basically include replacing laboratory equipment after each sample preparation; however, there are no recommended guidelines. In the present work we wanted to evaluate the risk of cross contamination during tissue processing using the routine precaution measures. Twenty-one surgical samples of lung adenocarcinoma were used, of which 7 contained EGFR exon 19 mutation, 7 contained EGFR exon 21 mutation (p.L858R) and 7 were EGFR wild-type. The samples were ordered by alternating the mutation group to maximize the potential for cross contamination and underwent tissue sectioning and de-paraffinization. The entire process was performed using the same tools. Following DNA extraction all samples underwent PCR amplification and were scrutinized for small fractions of EGFR mutation using deep sequencing with the Ion torrent PGM technology. Twenty samples yielded results. The fraction of mutated copies was 41 ± 23% (range 11-66) for the cases with known exon 19 mutation and 48±24% (range 0-65) for the cases with known exon 21 mutations. No in-frame exon 19 deletion mutations were identified in the wild-type (WT) and exon 21 groups. The fraction of EGFR exon 21 (codon 858) mutations was 0.018±0.014% (range 0-0.05%) in the WT and exon 19 groups, which was not statistically different than the background sequencing artifact noise for the same base-pair alteration (p = 0.21). Our results suggest that standard precautions are sufficient for molecular pathology diagnosis of surgical samples and are not associated with increased risk of cross contamination.

Femoral versus Multiple Nerve Blocks for Analgesia after Total Knee Arthroplasty.

BACKGROUND: The PROSPECT (Procedure-Specific Postoperative Pain Management) Group recommended a single injection femoral nerve block in 2008 as a guideline for analgesia after total knee arthroplasty. Other authors have recommended the addition of sciatic and obturator nerve blocks. The lateral femoral cutaneous nerve is also involved in pain syndrome following total knee arthroplasty. We hypothesized that preoperative blocking of all four nerves would offer superior analgesia to femoral nerve block alone. METHODS: This is a prospective, randomized, controlled, and observer-blinded clinical study. A total of 107 patients were randomly assigned to one of three groups: a femoral nerve block group, a multiple nerve block group, and a control group. All patients were treated postoperatively using patient-controlled intravenous analgesia with morphine. Pain intensity at rest, during flexion and extension, and morphine consumption were compared between groups over three days. RESULTS: A total of 90 patients completed the study protocol. Patients who received multiple nerve blocks experienced superior analgesia and had reduced morphine consumption during the postoperative period compared to the other two groups. Pain intensity during flexion was significantly lower in the "blocks" groups versus the control group. Morphine consumption was significantly higher in the control group. CONCLUSIONS: Pain relief after total knee arthroplasty immediately after surgery and on the first postoperative day was significantly superior in patients who received multiple blocks preoperatively, with morphine consumption significantly lower during this period. A preoperative femoral nerve block alone produced partial and insufficient analgesia immediately after surgery and on the first postoperative day. (Clinical trial registration number (NIH): NCT01303120).

Transversus Abdominis Plane Versus Ilioinguinal and Iliohypogastric Nerve Blocks for Analgesia Following Open Inguinal Herniorrhaphy.

OBJECTIVES: We hypothesized that preoperative (pre-op) ultrasound (US)-guided posterior transversus abdominis plane block (TAP) and US-guided ilioinguinal and iliohypogastric nerve block (ILI+IHG) will produce a comparable analgesia after Lichtenstein patch tension-free method of open inguinal hernia repair in adult men. The genital branch of the genitofemoral nerve will be blocked separately. METHODS: This is a prospective, randomized, controlled, and observer-blinded clinical study. A total of 166 adult men were randomly assigned to one of three groups: a pre-op TAP group, a pre-op ILI+IHG group, and a control group. An intraoperative block of the genital branch of the genitofemoral nerve was performed in all patients in all three groups, followed by postoperative patient-controlled intravenous analgesia with morphine. The pain intensity and morphine consumption immediately after surgery and during the 24 hours after surgery were compared between the groups. RESULTS: A total of 149 patients completed the study protocol. The intensity of pain immediately after surgery and morphine consumption were similar in the two "block" groups; however, they were significantly decreased compared with the control group. During the 24 hours after surgery, morphine consumption in the ILI+IHG group decreased compared with the TAP group, as well as in each "block" group versus the control group. Twenty-four hours after surgery, all evaluated parameters were similar. CONCLUSION: Ultrasound-guided ILI+IHG provided better pain control than US-guided posterior TAP following the Lichtenstein patch tension-free method of open inguinal hernia repair in men during 24 hours after surgery. (ClinicalTrials.gov number: NCT01429480.).

Comparison of the Supraclavicular, Infraclavicular and Axillary Approaches for Ultrasound-Guided Brachial Plexus Block for Surgical Anesthesia.

OBJECTIVE: We hypothesized that ultrasound (US)-guided technique of the supra- and infraclavicular and axillary approaches of brachial plexus block (BPB) will produce a high quality of surgical anesthesia for operations below the shoulder independently of the approach and body mass index (BMI). Intercostobrachial and medial brachial cutaneous nerves will be blocked separately because they are not a part of the brachial plexus. METHODS: This is a prospective randomized observer-blinded study. The three approaches of the US-guided BPB without neurostimulation were compared for quality, performance time, and correlation between performance time and BMI. Intercostobrachial and medial brachial cutaneous nerve blocks were used in all patients. RESULTS: A total of 101 patients were randomized into three groups: SCL (supraclavicular), ICL (infraclavicular), and AX (axillary). Seven patients were excluded due to various factors. All three groups were similar in demographic data, M:F proportion, preoperative diagnosis and type of surgery, anesthesiologists who performed the block, and surgical staff that performed the surgical intervention. The time between the end of the block performance and the start of the operation was also similar. The quality of the surgical anesthesia and discomfort during the operation were identical following comparison between groups. No direct positive correlation was observed between BMI and the block performance time. The time for the axillary block was slightly longer than the time for the supra- and infraclavicular approaches, but it had no practical clinical significance. Transient Horner syndrome was observed in three patients in the SCL group. No other adverse effects or complications were observed. CONCLUSIONS: All three approaches can be used for US-guided BPB with similar quality of surgical anesthesia for operations of below the shoulder. A block of the intercostobrachial and medial brachial cutaneous nerves is recommended. Obesity is not a significant factor in relation to the time of US-guided BPB performance, or the quality of surgical anesthesia. (ClinicalTrials.gov number, NCT01442558.).