Table 4 Multiple regression model of hospital length of stay for patients in the United States (excluding outliers)

  ≥ 20 - < 25

0.0151

0.1060

−0.1926 - 0.2228

0.0202

.887

  ≥ 25 - < 30

−0.0419

0.1039

−0.2455 - 0.1617

0.1624

.687

  ≥ 30 - < 35

−0.0808

0.1076

−0.2917 - 0.1301

0.564

.453

  ≥ 35

−0.2070

0.1053

−0.4134 -0.0007

3.8658

.049

  > 1 - < 4

−0.2885

0.0672

−0.4202 - 0.1568

18.4243

<.0001

  ≥ 4

−0.3768

0.0715

−0.5171 -0.2366

27.7411

<.0001

High risk surgery

0.2468

0.0706

0.1084–0.3851

12.223

.0005

Open surgery

0.1921

0.0643

0.0661–0.3181

8.9292

.003

  ≥ 2 - < 4

0.1932

0.0468

0.1016–0.2849

17.0719

<.0001

  ≥ 4

0.5523

0.0491

0.4562–0.6485

126.7597

<.0001

≥1 Respiratory Depression Episode

0.0846

0.0374

0.0112–0.1579

5.1058

.024

Hypertension

−0.0964

0.0379

−0.1707 - 0.0221

6.4728

.011

Chronic Heart Failure

0.2964

0.1116

0.0777–0.5152

7.0546

.008

Sepsis

0.5316

0.1083

0.3193–0.744

24.0798

<.0001