Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

Background Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications. Methods We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC). Findings In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683–0·717]). Interpretation In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required. Funding British Journal of Surgery Society

Incidence of Postoperative Residual Paralysis in a Nigerian Teaching Hospital

Background: Postoperative residual paralysis (PORP) is a known risk factor after general anesthesia (GA) for critical respiratory events and increased postoperative morbidity. PORP is defined as a train‑of‑four ratio (TOFR) of <0.9 using acceleromyography (AMG). TOFR <0.9 has been associated with increased risk of aspiration, obstruction of the upper airway and an impaired hypoxic ventilatory response. Aim: The aim of this study was to determine the incidence of PORP, associated factors related with its occurrence and critical respiratory events in the postanesthesia recovery room (PAR) at our institution. Methodology: Forty‑one adult patients were scheduled for elective surgeries requiring GA with the use of at least 1 dose of a nondepolarizing neuromuscular blocking drug (NMBD). An independent anesthetist quantitatively measured TOFR of recruited patients postoperatively in the recovery room using the TOF-watch SX acceleromyograph (Organon Teknika) 5 min after arrival. Results: The incidence of PORP was 75.6% (n = 31), with severe PORP (TOFR <0.7) seen in 41.5% (n = 17) of patients. Median time to full recovery in the PAR was 33 min (range 5–164 min). There was no statistical difference in the incidence of PORP related to the choice of NMBD (P = 0.186) or duration of surgery (P = 0.175). No respiratory complications or events were observed in patients with residual blockade. Conclusion: The incidence of PORP is quite high and undetected in our environment. Quantitative monitoring for residual paralysis is advocated as part of routine monitoring with the use of NMBDs for improved patient safety.Keywords: Incidence, neuromuscular blockade, Nigeria, postoperative, residualparalysi

One lung ventilation using double‑lumen tubes: Initial experience from Lagos, Nigeria

Background: One lung ventilation (OLV) is a technique routinely used in thoracic anesthesia to facilitate thoracic surgery. Double‑lumen tubes (DLT) remain the most popular and reliable choice for one lung ventilation especially in adult patients though use in Nigeria is limited. This study aimed to describe the experience in our institution with the use of double‑lumen tubes for one lung ventilation.Materials and Methods: This was a retrospective cross‑sectional study conducted on all patients who had double‑lumen tube intubations for one lung ventilation between March 2008 and Feb 2013.Results: A total of 55 patients (27 males and 28 females, with a mean age of 39.6 ± 15.7 years) had left double‑lumen tube intubations during the period. There were 30 left‑sided (54.5%) and 25 right‑sided (45.5%) surgical procedures performed. Tube position was verified by flexible bronchoscopy in 50 patients (91.9%) and by chest auscultation in 5 patients (9.1%) with satisfactory collapse in all but one of the procedures. The major surgical indications for one lung ventilation were Video‑assisted Thoracic Surgery (VATS) in 22 patients (40%) and Heller’s cardiomyotomy in 17 (30.9%). There were no mortalities and all patients had a complete recovery with no sequelae attributable to double‑lumen tube use or one lung ventilation.Conclusions: One lung ventilation is an integral component of modern anesthetic practice. It can be safely practiced in Nigeria with appropriate equipment and expertise. The use of DLT for OLV to enhance thoracic anesthetic practice should be encouraged in other Nigerian institutions.Key words: Anesthesia, double‑lumen tubes, Nigeria, one lung ventilation, thoraci

Imatinib derivatives as inhibitors of K562 cells in chronic myeloid leukemia

Imatinib was the first representative of the class of Breakpoint cluster region-Abelson murine leukemia viral oncogene homolog (BCR-ABL) tyrosine kinase inhibitors used for the treatment of chronic myeloid leukemia. Secondgeneration and third-generation drugs have been introduced in this therapy, affording increased patient survival. However, all BCR-ABL tyrosine kinase inhibitors have been shown to induce resistance, necessitating a search for new therapeutic options. The sunitinib, another tyrosine kinase inhibitor used in the treatment of renal cell carcinoma and gastrointestinal stromal tumors is an isatin derivative. Isatin nucleus is highly versatile for the preparation of new substances, and several tyrosine kinase inhibitors examples have been obtained using it. This work aimed to design, synthesize, and biological evaluation of new compounds using the K562 cell line, which constitutively expresses the active BCR-ABL enzyme. Three new series of imatinib derivatives have been planned from the imatinib, and all have a phenylaminopyrimidine group as the main pharmacophore. Sunitinib was used as a structural prototype to planning the series 1 (8a–e) of hybrids between sunitinib and imatinib. Series 2 and 3 are 2-oxo-2- phenyacetamide and 2,2-difluoro-2-phenylacetamide derivatives, respectively. Isatins were used as the starting materials for all series. Compounds were synthesized using simple methodologies and were obtained in high purities. The compounds were tested against K562 cells, and four showed a reduction in cell viability, with EC50 values ranging from 0.37 to 2.02 μM, some of which are close to the imatinib standard (0.21 μM).2030-01-0