OBJECTIVE: The aim of this study is to identify the postoperative ISIC changes relative to preoperative ISIC after OHS, and determine their predictors, including patient characteristics factors and IS performance parameters such as inspiration volumes (ISv) and frequencies (ISf).

METHODS: This is a prospective study with blinding procedures involving 95 OHS patients, aged 52.8±11.5 years, whose ISIC was measured preoperatively (PreopISIC) until fifth postoperative day (POD), while ISv and ISf monitored with an electronic device from POD1-POD4. Regression models were used to identify predictors of POD1 ISIC, POD2- POD5 ISIC increments, and the odds of attaining PreopISIC by POD5.

RESULTS: The ISIC reduced to 41% on POD1, increasing thereafter to 57%, 75%, 91%, and 106% from POD2-POD5 respectively. Higher PreopISIC (B=-0.01) significantly predicted lower POD1 ISIC, and, together with hyperlipedemia (B=11.52), which significantly predicted higher POD1 ISIC, explained 13% of variance. ISv at relative percentages of PreopISIC from POD1-POD4 (BPOD1=0.60, BPOD2=0.56, BPOD3=0.49, BPOD4=0.50) significantly predicted ISIC of subsequent PODs with variances at 23%, 24%, 17% and 25% respectively, but no association was elicited for ISf. IS performance findings facilitated proposal of a postoperative IS therapy target guideline. Higher ISv (B=0.05) also increased odds of patients recovering to preoperative ISIC on POD5 while higher PreopISIC (B=- 0.002), pain (B=-0.72) and being of Indian race (B=-1.73) decreased its odds.

METHODOLOGY: This prospective, randomized, controlled trial enrolled pregnant females undergoing LSCS after spinal anesthesia. The participants were randomized into two groups: a novel 3D device group and a traditional wedge group. Primary outcome measures included the incidence of SHS, while secondary outcomes included maternal hemodynamic parameters, fetal outcomes, feasibility, ease of use, and the safety profile of the devices.

RESULTS: Baseline characteristics were well balanced between the two groups. Although some differences in maternal hemodynamic parameters were noted, the incidence of SHS was significantly lower in the novel 3D device group than that in the traditional wedge group. Fetal outcomes did not differ significantly between the groups. The novel 3D device demonstrated high compatibility with various patient anatomies and was easy to integrate into routine practice. The adverse event profiles were similar between the groups.